convective drying of osmo-treated abalone (haliotis...

Research ArticleConvective Drying of Osmo-Treated Abalone(Haliotis rufescens) Slices Diffusion Modeling andQuality Features

Roberto Lemus-Mondaca 1 Sebastian Pizarro-Oteiacuteza2

Mario Perez-Won2 and Gipsy Tabilo-Munizaga3

1Departamento de Ciencia de los Alimentos y Tecnologıa Quımica Facultad de Ciencias Quımicas y FarmaceuticasUniversidad de Chile Santos Dumont 964 Independencia Santiago Chile2Departamento de Ingenierıa en Alimentos Universidad de La Serena Av Raul Bitran 1305 La Serena Chile3Departamento de Ingenierıa en Alimentos Universidad del Bıo-Bıo Av Andres Bello 720 Chillan Chile

Correspondence should be addressed to Roberto Lemus-Mondaca robertolemusciquchilecl

Received 17 October 2017 Revised 6 January 2018 Accepted 14 February 2018 Published 24 April 2018

Academic Editor Alex Martynenko

Copyright copy 2018 Roberto Lemus-Mondaca et al This is an open access article distributed under the Creative CommonsAttribution License which permits unrestricted use distribution and reproduction in any medium provided the original work isproperly cited

The focus of this research was based on the application of an osmotic pretreatment (15 NaCl) for drying abalone slices and itevaluates the influence of hot-air drying temperature (40ndash80∘C) on the product quality In addition the mass transfer kinetics ofsalt and water was also studiedThe optimal time of the osmotic treatment was established until reaching a pseudo equilibrium stateof the water and salt content (290min) The water effective diffusivity values during drying ranged from 376 to 475 times 10minus9m2sfor three selected temperatures (40 60 and 80∘C) In addition experimental data were fitted by Weibull distribution model Themodified Weibull model provided good fitting of experimental data according to applied statistical tests Regarding the evaluatedquality parameters the color of the surface showed a changemore significant at high temperature (80∘C) whereas the nonenzymaticbrowning and texture showed a decrease during drying process mainly due to changes in protein matrix and rehydration ratesrespectively In particular working at 60∘C resulted in dried samples with the highest quality parameters

1 Introduction

The red abalone (Haliotis rufensces) is an herbivorous gastro-pod mollusk living naturally in the bedrock of water between1 and 30m depth The culture of abalone has increasedconsiderably since it is highly appreciated as a seafood of highcommercial value especially in countries like China andJapan [1] enjoying the firm texture as well as cooked producttenderness [2] This species of abalone is considered exoticseafood and is one of the most expensive seafood products(Briones-Labarca et al 2011) From the above the Aquacul-ture in Chile has grown considerably while exports have beenimportant after copper forestry and fruits considering thatfor the future it will be one of the most important sourcesof food for the world This way the cultivation has been cur-rently focused on univalve (red abalone) bivalves (oysters)

crustaceans (lobsters) cephalopods (cuttlefish) and salmonspecies all with growing demand around the world [3]

Marine products are extremely perishable and the timeto spoilage depends mainly on species handling processingand storage temperature [4] Currently these products aresold as frozen canned or cooked frozen However the proce-dures involved can affect the quality attributes such as textureand taste [5] Therefore new treatments andor processes areneeded to minimize biological reactions and physicochemi-cal leading to the loss of food quality [5] in order to increaseproduct shelf-life

Many studies have focused on different methods ofpreservation with the hot-air drying being one of the mostimportant processes [6 7] This process reduces the wateractivity through loss of moisture preventing the growthand reproduction of microorganisms [8] Convective drying

HindawiJournal of Food QualityVolume 2018 Article ID 6317943 10 pageshttpsdoiorg10115520186317943

2 Journal of Food Quality

is one of the most used industrial methods for drying foodand biological materials in order to preserve its qualityand stability so avoiding spoilage and contamination duringthe storage period [1 9 10] However it is known that thedrying process causes the loss of function of the cell mem-branes especially when the temperature increases causingsignificant changes in sensory and nutritional food qualityThese disadvantages can be reduced using a combination ofdifferent pretreatments From these pretreatments the mostwidely used in convective drying are osmotic dehydrationblanching microwave drying and enzyme solution amongothers [11] Commonly marine products are immersed inconcentrated solutions to impregnate them with salt andorother curing ingredients (sucrose glucose fructose glycerolsorbitol and sodium chloride) to prolong shelf-life [5 12]The osmotic pretreatment scarcely affects the color flavorand texture of these products It diminishes also the loss ofnourishing substances and does not have a high exigency ofenergy due to the used temperatures generally that of theenvironment

Knowledge of the drying kinetics is used not only inthe evaluation process but rather to analyze and predict thedrying process variables tominimize damage to final productand optimize drying time and excessive energy consumption[1 9 13]This analysis can be performedwith differentmathe-matical models such as Newton Henderson-Pabis PageModified Page Weibull Two-Term Midilli-Kucuk and Log-arithmic models [14 15] Nonetheless in the literature thereis no information available about the use of Weibull distri-bution model for the marine product dehydration [16] TheWeibull model has been used to describe among others thekinetics high pressure removal of Bacillus subtilis [17] rehy-dration of breakfast cereals [18] loss of water during osmoticdehydration of food [19] and heat resistance of Bacilluscereus [20]

Thus the aim of this research was to study the influenceof drying temperature on the mass transfer kinetics ofosmotically pretreated abalone slices and to evaluate differentquality characteristics such as color rehydration capacitytexture profile (TPA) no enzymatic browning (NEB) totalvolatile basic nitrogen (TVBN) and antioxidant capacity ofthe dried-rehydrated product

2 Materials and Methods

21 Samples Preparation and Osmotic Pretreatment The redabalone (Haliotis rufescens) samples were collected from anaquaculture Company (Live Seafood Chile SA CoquimboChile) These samples with a weight of 200 plusmn 02 g weredelivered alive from the company to the university laboratoryThen they were slaughtered shucked cleaned and washedwith fresh water until the blue pigment haemocyanin wasremoved Finally the samples were cut into slices of 10mmlong times 01mm wide times 01 thick to consider one dimensionand were immersed in a salt solution (NaCl 15 g100mL)at 20∘C as proposed by Lemus-Mondaca et al [13] in thered abalone (Haliotis rufescens) and Boudhrioua et al [21] insardine filletsThebrine to sample ratiowasmaintained at 8 1in order to not dilute the osmotic solution by water removal

during experimentsThe brine was agitated continuously in awater bath (Quimis Q2152 Sao Paulo Brazil) to maintain auniform temperature The osmotic process was made up ofregular time intervals (0 15 30 45 60 120 180 240 300360 and 420min) until reaching an osmotic pseudo equilib-rium Moisture content was determined by AOAC methodn∘93406 (AOAC 1990) using an analytic balance (ChyoJex120 Kyoto Japan) with a plusmn00001 g accuracy and vacuumdrying oven (Gallenkamp OVA031 Leicester UK) As to saltcontent this one was measured by Mohr method [22] wheresalt content was expressed as g NaCl100 g sample All the ex-perimental determination was performed in triplicate

22 Drying Procedure Once the osmotic balance of the saltand water content has been reached convective drying wascarried outThe convective drying processwas performed in aconvective dryer tray designed and fabricated by the Depart-ment of Food Engineering at the University of La SerenaChile [7] Drying temperatures were 40 60 and 80∘C at aconstant air velocity 15 plusmn 02ms for each test with an envi-ronmental condition of 180 plusmn 01∘C and 681 plusmn 38 RH thelatter being measured by a digital hygrothermometer (ExtechInstrument Inc 451112 Waltham MA USA) The experi-ments ended when a state of pseudo equilibriumwas reachedat a constant weight between 22ndash18 humidity and 073ndash062water activity according to the temperatures evaluated Thesamples were sealed in polyethylene bags and each experi-ment wasmade in triplicateThe samples were sealed in poly-ethylene bags and each experiment was made in triplicate

23 Diffusion Coefficient In order to study the phenomenaof mass transfer during osmotic dehydration and convectivedrying process of abalone samples two components wereconsidered in each process (a) the water loss and salt gainfor OD and (b) the water loss for convective drying Fickrsquossecond law has been widely used to describe the dynamicsof the different drying processes for biological materials [23]The mathematical solution of Fickrsquos second law was usedto describe the period when internal mass transfer (wateror salt) is the controlling mechanism and one-dimensionaltransport in an infinite slab [24] shown in (1) whichcorresponds to the geometry of a semi-infinite slabThus thevariables of diffusion model are moisture loss (MR) (see (2))and salt gain rate (SR) (see (3)) [25] represented as follows

MR or SR = infinsum119894=0

8(2119894 + 1) 1205872 exp(

119863119890 (2119894 + 1) 120587211990541198712 ) (1)

For sufficiently long drying times the first term (119894 = 0) in theseries expansion of (1) gives a good estimation of the solutionand can be applied to determine the water and salt diffusioncoefficients (2) and (3) respectively [25]Then Fickrsquos 2nd law(see (1)) can be linearized from the slope (=120587211986311989041198712) where119863119908119890 and 119863119904119890 are moisture loss or salt gain respectively thatcan be obtained

Journal of Food Quality 3

MR = 119872119905119872119900 =81205872 exp(

119863119908119890120587211990541198712 ) (2)

SR = 119878119905119878119900 =81205872 exp(

119863119904119890120587211990541198712 ) (3)

The influence of drying temperature was determined accord-ing to the Arrhenius type equation (4) where kinetic param-eters (119864119886 and 119863119900) of this model can be estimated from theslope and intercept of the plot in 119863119890 versus the reciprocal ofabsolute temperature [10 23]

119863119890 = 119863119900exp(minus119864119886119877119879 ) (4)

24 Mathematical Modeling Commonly the authors pro-pose some simple and complex mathematical models tosimulate drying curves of foods that can provide an adequaterepresentation of the experimental results [26] Several mod-els exist in the literature to predict this process [27] Amongthese models the Weibull distribution model has been usedto describe diverse cases for example the removal of Bacillussubtilis for a high pressure treatment (Knorr 1996) rehydra-tion of breakfast cereals [18] and pressure inactivation ofbacteria [28] The mathematical expression was based on thediffusional mechanism of water expressed in

MRorSR = exp(minus[ 119905120573])120572 (5)

3 Quality Characteristics

31 ProximateAnalysis andWater Activity (119886119908) Themoisturecontent determination was performed according to AOACmethodology number 93406 using an analytical balance(Chyo Jex120 Kyoto Japan) with an accuracy of plusmn00001 gand a vacuum drying oven at 60∘C (Gallenkamp OVA031Leicester UK) The crude protein content was determinedby the Kjeldahl method (AOAC number 92039) applyinga conversion factor of 625 The fat content was determinedby the Soxhlet method (AOAC number 92039) and totalash by oxidation of the organic matter at 550∘C (AOACnumber 92308) The methods were performed according totheAOAC (1990)methodology and all the analyseswere donein triplicate In addition water activity (119886119908) was measured(AQUA LAB 4TE Pullman WA USA)

32 Nonenzymatic Browning (NEB) and Total Volatile BasicNitrogen (TVBN) Theproposedmethodology for determin-ing the NEB compounds dissolved in water rehydrationwas proposed by Vega-Galvez et al [29] The samples wererehydrated at a ratio (1 10) g sampleg water times 12 h Thenthe procedure was divided into three stages The first wasa clarification of rehydration water with centrifugation at3500 rpm times 15min The second step was a dilution (1 1)of this supernatant with ethanol (Sigma Chemical Co StLouis MO USA) at 95 (pa) centrifuged again to the sameconditions and finally the third was read (absorbance at420 nm) from the extracts that was determined to clear

quartz in buckets using a spectrophotometer (Spectronic20 Genesys Illinois USA) All measurements were done intriplicate and NEB was expressed as Absg dm [29] Totalvolatile basic nitrogen (TVBN) was determined on 5ndash16 g ofchopped abalone samples using direct distillation with MgOwith a Kjeldahl distillation apparatus and titration accordingto previous work [30] All measurements were done intriplicate

33 Surface Color Total color change (Δ119864) was calculatedfrom the initial sample surface color (fresh sample) versus thesurface color of the processed product (rehydrated sample)(see (6)) using a Colorimeter (HunterLab model MiniScanXEPlus Reston VAUSA) Color was determined by CIELabmethod where 119871lowast is whiteness or brightness 119886lowast is red-nessgreenness and 119887lowast is yellownessblueness coordinatesstandard illuminant11986365 and observer 10∘ [29] were obtainedwhere 119871119900 119886119900 and 119887119900 are the control values determined forfresh sample

Δ119864 = radic(119886lowast119903 minus 119886119900)2 + (119887lowast119903 minus 119887119900)2 + (119871lowast119903 minus 119871119900)2 (6)

34 Rehydration Indexes Dry samples were rehydrated usinga solidliquid mass ratio of 1 50 within a time of 12 hours atroom temperatureThe rehydration ratio (RR) was calculatedaccording to (7) and expressed as g absorbed waterg drymatter The water holding capacity (WHC) of the samplesrehydrated with the same above condition was centrifuged at3500119892 times 20min at 5∘C in tubes equipped with a plastic meshcentrally placed allowing water to drain from the sampleduring centrifugation This water holding capacity expressedas retainedwater100 gwaterwas determined according to (8)[29] All measurements were done in triplicate

RR = 119882119903 times 119883119903 minus119882119889 times 119883119889119882119889 (1 minus 119883119889) times 100 (7)

WHC = 119882119903 times 119883119903 minus119882119897119882119903 times 119883119903 times 100 (8)

35 Texture Profile Analysis (TPA) The texture profile ofsamples as an indicator of chewiness springiness resiliencecohesiveness and hardness was measured using a TextureAnalyzer (Texture Technologies Corp TA XT2 Scardale NYUSA)The probe had a puncture diameter of 20mm that was119875100 with a distance of 20mm and test speed of 17mmsThe maximum force was measured by making 1 puncturein each abalone sample using 10 slices per treatment TPAparameters including hardness gumminess chewiness elas-ticity cohesiveness and resilience were evaluated by a typicalforce-time curve [2]

36 Antioxidant Activity A lipid extraction was performedwith the Soxhelt method (AOACN∘ 92039)This extract wasreconstituted with ether ethanol 50 vv 50mL flask to reactwith the reagent 111015840-diphenyl-2-picrylhydrazyl (DPPH)modified according to Brand-Williams et al [31]The solutionof radical (DPPH) was prepared by dissolving 20mg DPPH


in 100mL of ether-ethanol (50)Then 01mL of sample wasextracted with 39mL of the DPPH solution Control samplewas prepared without adding extract Once the samplesspiked with DPPH it was placed in the darkness for 30minutes and the absorbance was measured at 517 nm using aspectrophotometer (Spectronic 20 Genesys Illinois USA)Results were expressed in micromoles of Trolox equivalentsTE [32] All measurements were done in triplicate

37 Statistical Analysis The fit quality of all models wasevaluated using the sum square error (SSE) (see (9)) andChi-square (1205942 see (10)) tests [33] The effect of air-dryingtemperature on each quality parameter was estimated byStatgraphics Plus v5 (Statistical Graphics Corp HerndonVA USA) The results were analyzed by an Analysis of Vari-ance (ANOVA) using a factorial design to one single factor(temperature) with 3 levels (40 60 and 80∘C) at a confidenceinterval of 95 with a Multiple Range Test (MRT)

SSE = 1119873infinsum119894=0

(MR or SR119890119894 minusMR or SR119888119894)2 (9)

1205942 = suminfin119894=0 (MR or SR119890119894 minusMR or SR119888119894)2119873 minus119898 (10)

4 Results and Discussion

41 Effective Moisture and Salt Diffusivity According to thekinetics of mass transfer of salt and water in the osmoticprocess (Figure 1) the optimum time was observed based on(2) and (3) This osmotic equilibrium was between 270 and300 minutes These values were similar to those estimatedby Telis et al [34] in caiman fillet and Mujaffar and Sankat[35] in shark muscleThe values of the effective water and saltdiffusivity in the osmotic process ((4) and (5)) were of 274 times10minus10m2s and 719 times 10minus10m2s respectively This occurs bythe simultaneous movements of NaCl and water in the tissuethat is the concentration differences and osmotic pressureexerted between the cell and the solution [36] Although thereis few data about this process applied to the abalone samplesa similar tendency was obtained by Corzo and Bracho [27]in the case of the sardine for value of 119863119908119890 and in the OD ofsardine fillets Boudhrioua et al [21] observed that the 119863119908119890values ranged from 240 times 10minus10 to 19 times 10minus8m2s

Concerning the effective moisture diffusivity in the dry-ing process the values oscillated from 376 times10minus9 to 476 times10minus9m2s according to the drying temperaturesThese valuesagreed with those found by Panagiotou et al [37] in seafooddrying which varied from 10minus11 to 10minus9m2s Ortiz et al [38]attained similar results with the salmon drying (Salmon salarL) at temperatures that ranged from 40 to 60∘C with valuesbetween 108 times10minus10 and 190 times 10minus10m2s Vega-Galvez et al[29] also obtained similar results in the jumbo squid dryingat temperatures from 40 to 90∘C with values of 078 times10minus9to 322 times 10minus9m2s together with Medina-Vivanco et al[39] for tilapia fillets drying The differences among thesevalues could be explained by the diversity of seafood species

that presented changes in temperature muscular type andposition fat content and presence or absence of skin [39]

Arrhenius equation (1199032 gt 085) was proposed by Vega-Galvez et al [29] The Arrhenius factor (1198630) that attaineda value of 317 times 10minus8m2s and the activation energy (119864119886)of 548 kJmol were calculated in agreement with (7) Suchvalues showed a clear dependence on the drying temperaturedemonstrating that (119863119908119890) values increase meaningfully astemperature increases Furthermore it can be concludedthat abalone was more sensitive to temperature than otherspecies according to its 119864119886 low-value if it is compared to thejumbo squid [29] which attained a value of 2893 (kJmol)and salmon [38] that showed a value of 2457 (kJmol) Theabalonersquos value was lower due to the difference in the com-position of its protein content compared to the other seafoodspecies mentioned before therefore it is concluded thatduring the drying period there would be a lower denatural-ization that would not hinder the water diffusional transfer(crustening) considering that a lower 119864119886 value means a high-er sensitivity within the evaluated temperature range [26 40]

42 Weibull Model Applied to Osmotic Dehydration Figure 1shows the transfer of kineticmass (water and salt) in a pseudoequilibrium state experimental and calculated by using theWeibull model to 15 NaCl with 1205942 = 0000595 SSE =0000463 and 1199032 = 094 The 120573 parameter both for salt gainand for water loss was 00093plusmn00103 to 7659plusmn14922 (min)respectivelyWith respect to the values of 120572 parameter for saltgain and water loss they were in a range of 0101 plusmn 0010to 0404 plusmn 0024 respectively Similar results were reportedby Corzo and Bracho [16] regarding sardinersquos water losswith 120572 values ranging from 0665 to 0469 under similarconcentrations

43 Weibull Model Applied to Drying Procedure The com-plexity of mass transfer process makes it difficult to obtainan accurate prediction because they depend on parametersand equilibrium conditions as well as the effective waterdiffusivity Thus the Weibullrsquos model was used (Figure 2)which shows the drying curves of 40 60 and 80∘C of abalonesamples pretreated osmotically and adjusted according to thismodel (00002 lt 1205942 lt 000048 000021 lt SSE lt 000040981 lt 1199032 lt 0993) It can be seen that all curves are expo-nential being typical for drying food [1] The behavior of thedrying curves was also reported by other authors when theyworked with lobster [29] The drying curves 60 and 80∘Cthat have a similar tendency are explained by the formationof a crust in the area of the abalone samples surface associatedwith osmotic pretreatment and thermal chockThis crust hasa significant resistance towatermigration [35] Drying curvesor drying rates depend on several factors some of them beingdirectly related to the product and others related to the air-drying temperature [41] Table 1 shows the moisture diffusiv-ity coefficient which was the most significant parameter inthe food drying [42] based on Fickrsquos second law [23]

In particular the values of 120572 and 120573 Weibull parametersshowed significant differences among evaluated tempera-tures with a 119901 value lt 005 Similar results were obtained byVega-Galvez et al [29] in the jumbo squid drying at the same


Table 1 Kinetic parameters of Weibull and Fick models for drying process

Model Parameter Drying temperature (∘C)40 60 80

Weibull 120573 14603 plusmn 1929a 9484 plusmn 2282b 6732 plusmn 1701c120572 0827 plusmn 0022a 0733 plusmn 0014b 0685 plusmn 0018c

Fick 119863119908119890 times 10minus9 376 plusmn 0146a 464 plusmn 0246b 475 plusmn 0052bIdentical letters above the values indicate no significant difference (119901 lt 005) Values are mean plusmn standard deviation (119899 = 3)

MR

s (di

men

sionl

ess)

MR

w (d

imen

sionl

ess)

Osmotic dehydration 15 NaCl Weibull model

600

1100

1600

2100

2600

030

040

050

060

070

080

090

100

100 200 300 4000Time (min)

Figure 1 Experimental water and salt transfer during osmotic proc-ess and calculated by Weibull model

temperatures Cunningham et al [43] explained that the 120573parameter represents the time required for 63 of the wholedrying process approximately Furthermore this parameterwas related to the mass transfer (min) at the beginning of theprocess therefore if the 120573 value was lower the transferencespeed was faster [44] and a reduction of 120572 parameter indi-cates greater water absorption and desorption of the dehy-drated product


441 Proximate Analysis andWater Activity (119886119908) The proxi-mate composition of osmotically treated samples was 766 forthe moisture content 133 for the protein content 173 for the

000010020030040050060070080090100

Moi

sture

ratio

(MR)

200 400 600 8000

Time (min)

＄ＬＳＣＨＡＮＧＪＬＮＯＬ 40∘



Weibull model

Figure 2 Experimental drying curvesmodeled by theWeibullmod-el

lipid content and 583 for the carbohydrate content (g100 gdm) furthermore the water activity value was 097 Whilethe moisture content values of dried samples ranged between2645 and 1803 g100 g dm the lipid content varied from726to 316 (g100 g dm) the carbohydrate content varied from2824 to 3258 g100 g dm and at last the protein contentshowed values from 5594 to 3593 g dm according to thetemperatures applied These values have a similar tendencyto the ones reported by other authors who studied drying andbrining jumbo squid [45] The safety limit for 119886119908 in the foodsis 06 [46]This research yielded values of 077plusmn002 to 067plusmn004 Chiou et al [45] obtained the same trend in cuttlefishdrying subjected to a pretreatment salt From the microbio-logical point of view theremight be some chemical biochem-ical or metabolic reactions of growth due to the quantityof water that is available However owing to the fact thatthe abalone was subjected to an osmotic pretreatment at 15NaCl it will cause a slower growth of some microorganismbecause of the difference in the osmotic pressure or because ofchloride ions that are deadly for some pathogens [47] affect-ing the enzymatic systems and consequently the chemicalreaction speed will be reduced

442 Surface Color and Nonenzymatic Browning (NEB)Color changes are in connection with the changes in thestructural protein that bring about a difference in lightdispersion properties on the surface of abalone samples


Table 2 Quality parameters such as TPA TVBN and antioxidant activity of fresh and dehydrated samples

Quality parameters Fresh Drying temperature (∘C)40 60 80

Texture profile analysis (TPA)Chewiness (mm) 2040 plusmn 976a 1308 plusmn 527a 2016 plusmn 246b 383325 plusmn 1693aSpringiness (mm) 068 plusmn 014a 070 plusmn 011ab 077 plusmn 008bc 085 plusmn 008cResilience 030 plusmn 007b 024 plusmn 003a 031 plusmn 002a 034 plusmn 004cCohesiveness 052 plusmn 009a 063 plusmn 005a 070 plusmn 003c 074 plusmn 004bHardness (Nmm) 2143 plusmn 1595a 2957 plusmn 1024ab 3706 plusmn 1516b 5522 plusmn 1816cTVBN (mg N100mg) 1057 plusmn 003a 4524 plusmn 009b 4766 plusmn 064c 5365 plusmn 034dAntioxidant activity (120583mol TEdm) 2882 plusmn 0003a 870 plusmn 0003b 855 plusmn 0273b 808 plusmn 0151cIdentical letters above the values indicate no significant difference (119901 lt 005) Values are mean plusmn standard deviation (119899 = 3)

like browning reactions [47] Figure 3 shows the changesof 119871lowast 119886lowast 119887lowast Δ119864 and NEB parameters from fresh andrehydrated samples According to ANOVA the luminosity(119871lowast) attained statistically significant differences in all thetreatments resulting in their decrease which were observedat 95 confidence level (119901 lt 005) among the mean valuesthat resulted in two homogeneous groups (40-60-80∘C andfresh) which can be explained because the luminosity wasaffected mainly by NaCl osmotic pretreatment [47] and thedrying temperature [1 29] The yellowness (119887lowast) increasedduring the drying temperature due to the browning [48] thatis it was proved that the temperatures used affected the 119887lowastparameter since these ones showed significant differences(119901 lt 005) in the average value for each temperature Similarvalues were obtained by Ortiz et al [38] in salmon dryingand by Vega-Galvez et al [1 29] in jumbo squid osmo-treateddrying This also occurs in 119886lowast parameter where there weresignificant statistical differences that attained a confidencevalue of 95 (119901 lt 005) As in the case of color variation(Δ119864) it also increasedwith the drying temperatures [38] from1235 to 1415 However the statistical study revealed that nosignificant differences were found among treatments that hada value 119901 gt 005 with a homogeneous group (40-60-80∘C)

Maillard type reactions or nonenzymatic browning(NEB) occurs because carbonyl compounds react withamino-groups when thermal treatments are applied on themuscular tissues that usually contain carbohydrates likeglycogen reducing sugars and nucleotides [49] which wasevidenced by the decrease in the value of 119871lowast and increase of119887lowast parameter The abalone is abundant in proteins and freeamino-acids therefore it can be observed that temperatureincrease brought about an important chestnut colored com-pound formation This was observed because the NEB com-pounds increased with the increase in temperature resultingin brown compoundsThe NEB treatment at 80∘C obtained a027plusmn0023 value Absg dm like Rahman [49] that evaluatedother seafood products

45 Texture Profile Analysis (TPA) Seafood muscle tissueis formed by muscle fibers cells located in the interstitialmedium and capillary space medium Muscular cells aremainly fibrils sarcoplasm and the connective tissue specifi-cally collagen [50] The principal structural factors that affect

aa

b

a a aa

b b c

a

ab

bc

b

cb

0

20

40

60

80

Fresh

Drying temperatures80∘60∘40∘

alowast

blowast

Llowast

NEBΔE

Figure 3 Effect of drying temperature on color differences (Δ119864)chromaticity coordinates 119871lowast 119886lowast and 119887lowast (whiteness or brightnessrednessgreenness and yellownessblueness) and nonenzymaticbrowning (NEB times 10minus2) of fresh and rehydrated abalone Differentletters above the bars indicate significant differences (119901 lt 005)

the texture are associated with the connective tissues andmyofibrils proteins (actins and myosin) [51] The myofibrilsproteins such as the myosin play an important role in thequality of meat owing to their capacity to hold water [52]

Based on the above the texture is one of the mostimportant characteristics that affect the quality of the productwhen it is chewed by the consumer [53] Table 2 shows theeffects of drying temperature on the fresh and rehydratedtexture samplesThe latter display a significant influence withincreasing temperature [29] Comparable results have beenreported in baking squid [53] and during shrimp drying[54] Drying causes protein denaturation by irreversiblestructural changes that lead to a change in texture [2] Driedabalone samples firmness is a critical parameter affectingthe quality and hence the acceptability of the product Alltreatments prior to drying showed an increase comparedto the fresh sample and can be explained by the effect ofthe drying temperature the NaCl concentration on tissueproteins [55] Firmness values between a fresh abalone and adried-hydrated one at the highest drying temperature varied


from 2143 to 5412Nmm The same tendency was reportedby Vega-Galvez et al [29] for the osmo-treated cuttlefishdrying and by Ortiz et al [38] on salmon drying

46 Rehydration Indexes Most products dehydrated arerehydrated before consumption Rehydration can be regardedas an indirect measure of tissue damage caused by drying[29] Figure 4 shows the rehydration ratio (RR) together withthe water holding capacity (WHC) for different treatmentsused This figure indicated that treatment at 60∘C obtainedRR increased compared to the other treatments (126 gabsorbed waterg dry matter) The treatment at 40∘C revealsslightly lower value as compared to 60 to 80∘C Moreover itis generally accepted that the degree of rehydration dependson the degree of cell structural alteration [47] because ifthe drying temperature increases the higher the rehydrationcapacity will be due to its lower water retention capacity thatwas caused by structural damage at the cellular level result-ing among other effects in leaching of soluble solids [56]

WHCvalue shows a tendency to decrease as the treatmenttemperature increases thus at 40∘C the treatment has thehighest water holding capacity (9896 g retained water100 gwater) and the lowest at 80∘C (9525 g retained water100 gwater) Similar results were reported by other authors whodescribed that drying temperature was the main factor ofWHC decrease becoming an obstacle to retain this water Inparticular Vega-Galvez et al [29] working in cuttlefish foundsimilar results Besides it must be pointed out that abaloneand all the meat species have a good water holding capacitydue to their protein feature of a myofibril origin [52]

47 Antioxidant Capacity The results in Table 2 show thatthe antioxidant capacity obtained a decrease with the processtemperatures that is it can be observed that the variabletemperature has a significant effect on the antioxidant activityof the abalone samples These results also were reported byBennett et al [57] concluding that the drying and processingconditions affect the antioxidant capacity of foods All thetreatments showed a diminishing of such an activity ascompared to a fresh sample that obtained 28824120583mol TEgdm A similar behavior was also observed at 60∘C and 80∘Cdue to the same period under thermal process This canbe explained by the osmotic pretreatment that the abalonehas which might produce NaCl crystals as a barrier to thewater outlet (Collignan et al 2000) affecting the dryingprocess The antioxidant activity of seafood has been relatedto proteins and has been reported of different peptides havingantioxidant effects [58] However the relationship betweenantioxidant activity and content of active peptide has not beenfully studied yet in the process [58]

48 Total Volatile Basic Nitrogen (TVBN) TVBN values thatare reported in this research are in a range from 1057to 5365mg N100 g from samples fresh and dehydratedwhich can be better valued from Table 2 These values varyaccording to the fishtailed species the environment physi-ological conditions processing and storage conditions [48]

920

930

940

950

960

970

980

990

1000

WHCRR

ba

c

ba

g w

ater

)W

HC

(g re

tain

ed w

ater

100

ab

40 60 80(∘C)

000

020

040

060

080

100

120

140

RR (g

abso

rbed

wat

erg

dm

)

Figure 4 Effect of air-drying temperature on the rehydration ratio(RR) and the water holding capacity (WHC) for dry-rehydratedabalone samples Identical letters above the bars indicate no signifi-cant difference (119901 lt 005)

Table 2 shows an increase in the amount of TVBN as the tem-perature increases due to the low molecular weight volatilecompounds that increase the amount of nitrogen consider-ably with the heat treatment [29] Similar results were foundby Robles et al [59] when applying thermal treatments oncrabs (Homalaspis plana) The total basic volatile nitrogencontent (TVBN) has been worldwide used as an indicator offish quality [60]The fresh value was 1057plusmn003mgN100 gsample that can be compared to fresh seafood reported byother authors [59]

TVBN content increases by the thermal treatment dueto the longer heat exposition according to Gallardo et al[61 62] During thermal treatment the composition andproportion of the nitrogenous compounds cause changesin the aminersquos molecular weight contents that is TVBNincreases as a consequence of some amino-acids degradation[59] TVBN values of meat subjected to a thermal treatmentare always higher than fresh meat [61] Studies carried out incanned mussels and squids and other fish species that under-went some thermal treatment showed TVBN values of 425ndash573mg100 g of muscles [62] According to ANOVA (119901 lt005) there was a significant difference between the averagevalues of the total content of volatile nitrogen for treatmentsstudied

5 Conclusion

This study has shown that the concentration of the osmotictreatment influences directly the diffusional coefficient ofwater and salt in the process obtaining a balance between270 lt min lt 300 These values ranged from 274 to 719 times10minus10m2s respectively As for the effective diffusivity ofwaterin the drying process therewas a tendency to increase regard-ing the evaluated temperatures whose values oscillated from376 to 476 times 10minus9m2s The Weibull model obtained a goodfit in the OD and drying corroborating with statistical test00006 lt 1205942 lt 109 00005 lt SSE lt 08934 and 091 lt 1199032 lt094 The drying temperature significantly influenced the


physical chemical and nutritional properties of abalonesamples Discoloration of product was more evident at highdrying temperatures where combined effects of nonenzy-matic browning as well as protein denaturation modified theabalone samples original color According to the drying tem-perature the RR andWHC indexes showed a decrease whilethe texture presented an increase TVBN and antioxidantactivity values presented a decrease with increased temper-ature Therefore the results of this work indicate that thedrying kinetics along with quality aspects of dried abalonescan be used to improve the final characteristics of the productand predict a suitable drying treatment at 60∘C under anosmotic pretreatment (15 NaCl)

Nomenclature

OD Osmotic dehydration119863119890 Mass effective diffusivity (m2s)119878119905 Salt content (g NaClg dry matter dm)119872119905 Water content (g waterg dm)SR Salt ratio (dimensionless)MR Moisture ratio (dimensionless)119871 Sample thickness (m)119864119886 Activation energy (kJmol)119871lowast Whitenessdarkness color parameter119886lowast Rednessgreenness color parameter119887lowast Yellownessblueness color parameterRH Relative humidity ()RR Rehydration ratio (g absorbed waterg dry

matter)WHC Water holding capacity (g retained

water100 g water)TE 120583mol of trolox equivalents119877 Universal gas constant (8314 Jmol K)119863119900 Arrhenius factor (m2s)119879 Temperature (∘C or K)119882 Weight of the sample (g)119905 Time (min)119873 Number of data

Greek Letters

120572 Shape parameter of Weibull model (dimensionless)120573 Scale parameter of Weibull model (min)

Subscripts

119908 Water119904 Salt119905 At time119900 Initial119903 Rehydrated sample119889 Dried sample119897 Drained liquid after centrifugation119894 Number of terms119888 Calculated119890 Experimental

Conflicts of Interest

The authors declare that there are no conflicts of interestregarding the publication of this paper as well as the receivedfunding

Acknowledgments

The authors gratefully acknowledge the financial supportprovided by Concurso DIULS Apoyo Tesis de PostgradoProject no PT14332 and FONDECYT Regular Project no1140067

References

[1] A Vega-Galvez R Lemus-Mondaca D Plaza-Saez and MPerez-Won ldquoEffect of air-temperature and diet compositionon the drying process of pellets for japanese abalone (haliotisdiscus hannai) feedingrdquo Ciencia e Tecnologia de Alimentos vol31 no 3 pp 694ndash702 2011

[2] B Zhu X Dong L Sun et al ldquoEffect of thermal treatment onthe texture and microstructure of abalone muscle (Haliotisdiscus)rdquo Food Science and Biotechnology vol 20 no 6 pp 1467ndash1473 2011

[3] Sernapesca 2015 Servicio nacional de Pesca de Chile Leyes yReglamentos Normativas y Valparaıso Ministerio de Econo-mia Fomento y Turismo Disponible en httpwwwsernapescacl Acesso em Jun 10 2015

[4] T Tsironi I Salapa and P Taoukis ldquoShelf life modelling ofosmotically treated chilled gilthead seabream filletsrdquo InnovativeFood Science and Emerging Technologies vol 10 no 1 pp 23ndash312009

[5] A Z Valencia-Perez M H Garcıa-Morales J L Cardenas-Lopez J R Herrera-Urbina O Rouzaud-Sandez and J MEzquerra-Brauer ldquoEffect of thermal process on connectivetissue from jumbo squid (Dosidicus gigas) mantlerdquo FoodChemistry vol 107 no 4 pp 1371ndash1378 2008

[6] B S M Mahmoud K Yamazaki K Miyashita Y Kawai I-SShin and T Suzuki ldquoPreservative effect of combined treatmentwith electrolyzed NaCl solutions and essential oil compoundson carp fillets during convectional air-dryingrdquo InternationalJournal of Food Microbiology vol 106 no 3 pp 331ndash337 2006

[7] A Vega-Galvez K Di Scala K Rodrıguez et al ldquoEffect of air-drying temperature on physico-chemical properties antioxi-dant capacity colour and total phenolic content of red pepper(Capsicum annuum L var Hungarian)rdquo Food Chemistry vol117 no 4 pp 647ndash653 2009

[8] S Bellagha A Sahli A Farhat N Kechaou and A GlenzaldquoStudies on salting and drying of sardine (Sardinella aurita)Experimental kinetics andmodelingrdquo Journal of Food Engineer-ing vol 78 no 3 pp 947ndash952 2007

[9] E K Akpinar ldquoDetermination of suitable thin layer dryingcurve model for some vegetables and fruitsrdquo Journal of FoodEngineering vol 73 no 1 pp 75ndash84 2006

[10] K Di Scala and G Crapiste ldquoDrying kinetics and quality chan-ges during drying of red pepperrdquo LWT- Food Science andTechnology vol 41 no 5 pp 789ndash795 2008

[11] N E Perez and M E Schmalko ldquoConvective drying of pump-kin Influence of pretreatment and drying temperaturerdquo Journalof Food Process Engineering vol 32 no 1 pp 88ndash103 2009


[12] R Lemus-Mondaca M Miranda A Andres Grau V BrionesR Villalobos and A Vega-Galvez ldquoEffect of osmotic pretreat-ment on hot air drying kinetics and quality of Chilean papaya(Carica pubescens)rdquoDrying Technology vol 27 no 10 pp 1105ndash1115 2009

[13] R Lemus-Mondaca S Noma N Igura M Shimoda and MPerez-Won ldquoKinetic Modeling and Mass Diffusivities duringOsmotic Treatment of Red Abalone (Haliotis rufescens) SlicesrdquoJournal of Food Processing and Preservation vol 39 no 6 pp1889ndash1897 2015

[14] I Doymaz ldquoDrying of leek slices using heated airrdquo Journal ofFood Process Engineering vol 31 no 5 pp 721ndash737 2008

[15] L AitMohamed C S EthmaneKaneM Kouhila A JamaliMMahrouz and N Kechaou ldquoThin layer modelling of Gelidiumsesquipedale solar drying processrdquo Energy Conversion andManagement vol 49 no 5 pp 940ndash946 2008

[16] O Corzo and N Bracho ldquoApplication of Weibull distributionmodel to describe the vacuum pulse osmotic dehydration ofsardine sheetsrdquo LWT- Food Science and Technology vol 41 no6 pp 1108ndash1115 2008

[17] V Heinz and D Knorr ldquoHigh pressure inactivation kinetics ofBacillus subtilis cells by a three-state-model considering dis-tributed resistancemechanismsrdquoFoodBiotechnology vol 10 no2 pp 149ndash161 1996

[18] M F Machado F A R Oliveira and L M Cunha ldquoEffect ofmilk fat and total solids concentration on the kinetics ofmoisture uptake by ready-to-eat breakfast cerealrdquo Int J Food SciTech34 pp 47ndash57 1999

[19] L M Cunha F A R Oliveira A P Aboim and J M FrıasldquoaStochastic approach to the modelling of water losses duringosmotic dehydration and improved parameter estimationrdquo inProceedings of the aStochastic approach to the modelling ofwater losses during osmotic dehydration and improved parameterestimation International J Food Sci Tech 36 253ndash262 vol 36 pp253ndash262 2001

[20] A Fernandez J Collado L M Cunha M J Ocio and A Mar-tinez ldquoEmpirical model building based onWeibull distributionto describe the joint effect of pH and temperature on the termalresistance of Bacillus cereus in vegetable substraterdquo Int J FoodMicr pp 77ndash147 2002

[21] N Boudhrioua N Djendoubi S Bellagha and N KechaouldquoStudy of moisture and salt transfers during salting of sardinefilletsrdquo Journal of Food Engineering vol 94 no 1 pp 83ndash892009

[22] J M Barat L Gallart-Jornet A Andres L Akse M Carlehogand O T Skjerdal ldquoInfluence of cod freshness on the saltingdrying and desalting stagesrdquo Journal of Food Engineering vol73 no 1 pp 9ndash19 2006

[23] Y Wang M Zhang and A S Mujumdar ldquoConvective dry-ing kinetics and physical properties of silver carp (Hypoph-thalmichthys molitrix) filletsrdquo Journal of Aquatic Food ProductTechnology vol 20 no 4 pp 361ndash378 2011

[24] J Crank The Mathematics of Diffusion Clarendon PressOxford UK 2nd edition 1975

[25] E Uribe M Miranda A Vega-Galvez I Quispe R Claverıaand K Di Scala ldquoMass Transfer Modelling During OsmoticDehydration of Jumbo Squid (Dosidicus gigas) Influence ofTemperature onDiffusionCoefficients andKinetic ParametersrdquoFood and Bioprocess Technology vol 4 no 2 pp 320ndash326 2011

[26] S Simal A Femenia M C Garau and C Rossello ldquoUse ofexponential Pagersquos and diffusional models to simulate the

drying kinetics of kiwi fruitrdquo Journal of Food Engineering vol66 no 3 pp 323ndash328 2005

[27] O Corzo and N Bracho ldquoApplication of Normalized WeibullModel in the Osmotic Dehydration of Sardine Sheetsrdquo RevistaCientıfica vol XIX no 4 pp 400ndash407 2009

[28] S Buzrul H Alpas and F Bozoglu ldquoUse of Weibull frequencydistributionmodel to describe the inactivation of Alicyclobacil-lus acidoterrestris by high pressure at different temperaturesrdquoFood Research International vol 38 no 2 pp 151ndash157 2005

[29] A Vega-Galvez M Miranda R Claverıa et al ldquoEffect of airtemperature on drying kinetics and quality characteristics ofosmo-treated jumbo squid (Dosidicus gigas)rdquo LWT- FoodScience and Technology vol 44 no 1 pp 16ndash23 2011

[30] J R BOTTA J T LAUDER and M A JEWER ldquoEffect ofMethodology on Total Volatile Basic Nitrogen (TVB-N) Deter-mination as an Index of Quality of Fresh Atlantic Cod (Gadusmorhua)rdquo Journal of Food Science vol 49 no 3 pp 734ndash7361984

[31] W Brand-Williams M E Cuvelier and C Berset ldquoUse of a freeradical method to evaluate antioxidant activityrdquo LWT - FoodScience and Technology vol 28 no 1 pp 25ndash30 1995

[32] P Molyneux ldquoThe use of the stable radical Diphenylpicryl-hydrazyl (DPPH) for estimating antioxidant activityrdquo Songk-lanakarin Journal of Science and Technology vol 26 no 2 pp211ndash219 2004

[33] Y Wang J Yue Z Liu et al ldquoImpact of Far-Infrared RadiationAssisted Heat Pump Drying on Moisture Distribution andRehydration Kinetics of Squid Fillets During RehydrationrdquoJournal of Aquatic Food Product Technology vol 25 no 2 pp147ndash155 2016

[34] V R N Telis P F Romanelli A L Gabas and J Telis-RomeroldquoSalting kinetics and salt diffusivities in farmedPantanal caimanmusclerdquoPesquisaAgropecuaria Brasileira vol 38 no 4 pp 529ndash535 2003

[35] S Mujaffar and C K Sankat ldquoThe mathematical modelling ofthe osmotic dehydration of shark fillets at different brine tem-peraturesrdquo International Journal of Food Science amp Technologyvol 41 no 4 pp 405ndash416 2006

[36] M F Villacıs N K Rastogi and V M BalasubramaniamldquoEffect of high pressure on moisture and NaCl diffusion intoturkey breastrdquo LWT- Food Science and Technology vol 41 no 5pp 836ndash844 2008

[37] N M Panagiotou M K Krokida Z B Maroulis and G DSaravacos ldquoMoisture diffusivity Literature data compilation forfoodstuffsrdquo International Journal of Food Properties vol 7 no 2pp 273ndash299 2004

[38] J Ortiz R Lemus-Mondaca A Vega-Galvez et al ldquoInfluence ofair-drying temperature on drying kinetics colour firmness andbiochemical characteristics of Atlantic salmon (Salmo salar L)filletsrdquo Food Chemistry vol 139 no 1-4 pp 162ndash169 2013

[39] M Medina-Vivanco P J A Do Sobral and M D HubingerldquoOsmotic dehydration of tilapia fillets in limited volume ofternary solutionsrdquoChemical Engineering Journal vol 86 no 1-2pp 199ndash205 2002

[40] I Doymaz ldquoDrying characteristics and kinetics of okrardquo Journalof Food Engineering vol 69 no 3 pp 275ndash279 2005

[41] P Fito A M Andres J M Barat A M Albors and A MAndres Introduccion al Secado de Alimentos por Aire CalienteEditorial UPV Valencia Espana 2001

[42] A Vega P Fito A Andres and R Lemus ldquoMathematical mod-eling of hot-air drying kinetics of red bell pepper (var


Lamuyo)rdquo Journal of Food Engineering vol 79 no 4 pp 1460ndash1466 2007

[43] S E Cunningham W A M McMinn T R A Magee andP S Richardson ldquoModelling water absorption of pasta duringsoakingrdquo Journal of Food Engineering vol 82 no 4 pp 600ndash607 2007

[44] M F Machado F A R Oliveira V Gekas and R P SinghldquoKinetics of moisture uptake and soluble-solids loss by puffedbreakfast cereals immersed in waterrdquo International Journal ofFood Science amp Technology vol 33 no 3 pp 225ndash237 1998

[45] T Chiou H Chang L Lo H Lan and C Shiau ldquoChanges inchemical constituents and physical ındices during processing ofdried-seasoned squidrdquo Fish Sci pp 66ndash708 2000

[46] A Vega-Galvez M Palacios F Boglio C Passaro C Jerez andR Lemus-Mondaca ldquoDeshidratacion osmotica de la papayachilena (Vasconcellea pubescens) e influencia de la temperaturay concentracion de la solucion sobre la cinetica de transferenciade materiardquo Ciencia e Tecnologia de Alimentos vol 27 no 3 pp470ndash477 2007

[47] N Guizani A O Al-Shoukri A Mothershaw and M S Rah-man ldquoEffects of salting and drying on shark (Carcharhinussorrah)meat quality characteristicsrdquoDrying Technology vol 26no 6 pp 705ndash713 2008

[48] S-C Shen K-C Tseng and J S-BWu ldquoAn analysis ofMaillardreaction products in ethanolic glucose-glycine solutionrdquo FoodChemistry vol 102 no 1 pp 281ndash287 2007

[49] S Rahman ldquoDrying of fish and seafoodrdquo in Handbook ofindustrial drying A S and Mujumdar Eds CRC Press BocaRaton FL USA 3 edition 2006

[50] S K Oslashiseth C Delahunty M Cochet and L Lundin ldquoWhy isabalone so chewy structural characterization and relationshipto textural attributesrdquo Journal of Shellfish Research vol 32 no 1pp 73ndash79 2013

[51] F Erdogdu and M Balaban ldquoThermal processing effects on thetextural attributes of previously frozen shrimprdquo J Aquat FoodProd Tech pp 67ndash84 2000

[52] N Chapleau C Mangavel J-P Compoint and M De Lambal-lerie-Anton ldquoEffect of high-pressure processing onmyofibrillarprotein structurerdquo Journal of the Science of Food andAgriculturevol 84 no 1 pp 66ndash74 2004

[53] W S Otwell and D D Hamann ldquoTextural characterizati onof squid (loligo pealei l) instrumental and panel evaluationsrdquoJournal of Food Science vol 44 no 6 pp 1636ndash1643 1979

[54] Y Namsanguan W Tia S Devahastin and S SoponronnaritldquoDrying kinetics and quality of shrimp undergoing differenttwo-stage drying processesrdquo Drying Technology vol 22 no 4pp 759ndash778 2004

[55] L Gallart-Jornet J M Barat T Rustad U Erikson I Escricheand P Fito ldquoInfluence of brine concentration on Atlantic sal-mon fillet saltingrdquo Journal of Food Engineering vol 80 no 1pp 267ndash275 2007

[56] P Garcıa-Pascual N Sanjuan R Melis and A MuletldquoMorchella esculenta (morel) rehydration process modellingrdquoJournal of Food Engineering vol 72 no 4 pp 346ndash353 2006

[57] L E Bennett H Jegasothy I Konczak D Frank S Sudhar-marajan and P R Clingeleffer ldquoTotal polyphenolics and anti-oxidant properties of selected dried fruits and relationships todrying conditionsrdquo Journal of Functional Foods vol 3 no 2 pp115ndash124 2011

[58] S Jongberg C U Carlsen and L H Skibsted ldquoPeptides asantioxidants and carbonyl quenchers in biological model sys-temsrdquo Free Radical Research vol 43 no 10 pp 932ndash942 2009

[59] V Robles L Abugoch J Vinagre et al ldquoEfecto de tratamientostermicos sobre las caracterısticas quımicas de carne de jaibamorardquo Homalaspis plana vol 53 pp 191ndash223 2003

[60] L Pivarnik P Ellis X Wang and T Reilly ldquoStandardization ofthe ammonia electrode method for evaluating seafood qualityby correlation to sensory analysisrdquo Journal of Food Science vol66 no 7 pp 945ndash952 2001

[61] J M Gallardo R I Perez-Martin J M Franco S Aubourgand C G Sotelo ldquoChanges in volatile bases and trimethylamineoxide during the canning of albacore (Thunnus alalunga)rdquoInternational Journal of Food Science amp Technology vol 25 no1 pp 78ndash81 1990

[62] J M Gallardo R Perez-Martin J M Franco and S AubourgldquoChemical composition and evolution of nitrogen compoundsduring the processing and storage of canned albacore (Thunnusalalungardquo in ProcMOCCA pp 51ndash58 Chemical compositionand evolution of nitrogen compounds during the processingand storage of canned albacore (Thunnus alalunga) ProcMOCCA 1 51-58 1984

Hindawiwwwhindawicom

International Journal of

Volume 2018

Zoology

Hindawiwwwhindawicom Volume 2018

Anatomy Research International

PeptidesInternational Journal of



Journal of Parasitology Research

GenomicsInternational Journal of


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The Scientific World Journal

Volume 2018


BioinformaticsAdvances in

Marine BiologyJournal of



Neuroscience Journal


BioMed Research International

Cell BiologyInternational Journal of



Biochemistry Research International

ArchaeaHindawiwwwhindawicom Volume 2018


Genetics Research International


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Enzyme Research



MicrobiologyHindawiwwwhindawicom

Nucleic AcidsJournal of

Volume 2018

Submit your manuscripts atwwwhindawicom


is one of the most used industrial methods for drying foodand biological materials in order to preserve its qualityand stability so avoiding spoilage and contamination duringthe storage period [1 9 10] However it is known that thedrying process causes the loss of function of the cell mem-branes especially when the temperature increases causingsignificant changes in sensory and nutritional food qualityThese disadvantages can be reduced using a combination ofdifferent pretreatments From these pretreatments the mostwidely used in convective drying are osmotic dehydrationblanching microwave drying and enzyme solution amongothers [11] Commonly marine products are immersed inconcentrated solutions to impregnate them with salt andorother curing ingredients (sucrose glucose fructose glycerolsorbitol and sodium chloride) to prolong shelf-life [5 12]The osmotic pretreatment scarcely affects the color flavorand texture of these products It diminishes also the loss ofnourishing substances and does not have a high exigency ofenergy due to the used temperatures generally that of theenvironment

Knowledge of the drying kinetics is used not only inthe evaluation process but rather to analyze and predict thedrying process variables tominimize damage to final productand optimize drying time and excessive energy consumption[1 9 13]This analysis can be performedwith differentmathe-matical models such as Newton Henderson-Pabis PageModified Page Weibull Two-Term Midilli-Kucuk and Log-arithmic models [14 15] Nonetheless in the literature thereis no information available about the use of Weibull distri-bution model for the marine product dehydration [16] TheWeibull model has been used to describe among others thekinetics high pressure removal of Bacillus subtilis [17] rehy-dration of breakfast cereals [18] loss of water during osmoticdehydration of food [19] and heat resistance of Bacilluscereus [20]

Thus the aim of this research was to study the influenceof drying temperature on the mass transfer kinetics ofosmotically pretreated abalone slices and to evaluate differentquality characteristics such as color rehydration capacitytexture profile (TPA) no enzymatic browning (NEB) totalvolatile basic nitrogen (TVBN) and antioxidant capacity ofthe dried-rehydrated product

2 Materials and Methods

21 Samples Preparation and Osmotic Pretreatment The redabalone (Haliotis rufescens) samples were collected from anaquaculture Company (Live Seafood Chile SA CoquimboChile) These samples with a weight of 200 plusmn 02 g weredelivered alive from the company to the university laboratoryThen they were slaughtered shucked cleaned and washedwith fresh water until the blue pigment haemocyanin wasremoved Finally the samples were cut into slices of 10mmlong times 01mm wide times 01 thick to consider one dimensionand were immersed in a salt solution (NaCl 15 g100mL)at 20∘C as proposed by Lemus-Mondaca et al [13] in thered abalone (Haliotis rufescens) and Boudhrioua et al [21] insardine filletsThebrine to sample ratiowasmaintained at 8 1in order to not dilute the osmotic solution by water removal

during experimentsThe brine was agitated continuously in awater bath (Quimis Q2152 Sao Paulo Brazil) to maintain auniform temperature The osmotic process was made up ofregular time intervals (0 15 30 45 60 120 180 240 300360 and 420min) until reaching an osmotic pseudo equilib-rium Moisture content was determined by AOAC methodn∘93406 (AOAC 1990) using an analytic balance (ChyoJex120 Kyoto Japan) with a plusmn00001 g accuracy and vacuumdrying oven (Gallenkamp OVA031 Leicester UK) As to saltcontent this one was measured by Mohr method [22] wheresalt content was expressed as g NaCl100 g sample All the ex-perimental determination was performed in triplicate

22 Drying Procedure Once the osmotic balance of the saltand water content has been reached convective drying wascarried outThe convective drying processwas performed in aconvective dryer tray designed and fabricated by the Depart-ment of Food Engineering at the University of La SerenaChile [7] Drying temperatures were 40 60 and 80∘C at aconstant air velocity 15 plusmn 02ms for each test with an envi-ronmental condition of 180 plusmn 01∘C and 681 plusmn 38 RH thelatter being measured by a digital hygrothermometer (ExtechInstrument Inc 451112 Waltham MA USA) The experi-ments ended when a state of pseudo equilibriumwas reachedat a constant weight between 22ndash18 humidity and 073ndash062water activity according to the temperatures evaluated Thesamples were sealed in polyethylene bags and each experi-ment wasmade in triplicateThe samples were sealed in poly-ethylene bags and each experiment was made in triplicate

23 Diffusion Coefficient In order to study the phenomenaof mass transfer during osmotic dehydration and convectivedrying process of abalone samples two components wereconsidered in each process (a) the water loss and salt gainfor OD and (b) the water loss for convective drying Fickrsquossecond law has been widely used to describe the dynamicsof the different drying processes for biological materials [23]The mathematical solution of Fickrsquos second law was usedto describe the period when internal mass transfer (wateror salt) is the controlling mechanism and one-dimensionaltransport in an infinite slab [24] shown in (1) whichcorresponds to the geometry of a semi-infinite slabThus thevariables of diffusion model are moisture loss (MR) (see (2))and salt gain rate (SR) (see (3)) [25] represented as follows

MR or SR = infinsum119894=0

8(2119894 + 1) 1205872 exp(

119863119890 (2119894 + 1) 120587211990541198712 ) (1)

For sufficiently long drying times the first term (119894 = 0) in theseries expansion of (1) gives a good estimation of the solutionand can be applied to determine the water and salt diffusioncoefficients (2) and (3) respectively [25]Then Fickrsquos 2nd law(see (1)) can be linearized from the slope (=120587211986311989041198712) where119863119908119890 and 119863119904119890 are moisture loss or salt gain respectively thatcan be obtained


MR = 119872119905119872119900 =81205872 exp(

119863119908119890120587211990541198712 ) (2)

SR = 119878119905119878119900 =81205872 exp(

119863119904119890120587211990541198712 ) (3)


119863119890 = 119863119900exp(minus119864119886119877119879 ) (4)


MRorSR = exp(minus[ 119905120573])120572 (5)















SSE = 1119873infinsum119894=0
















MR

s (di

men

sionl

ess)

MR

w (d

imen

sionl

ess)


600

1100

1600

2100

2600

030

040

050

060

070

080

090

100

100 200 300 4000Time (min)





000010020030040050060070080090100

Moi

sture

ratio

(MR)

200 400 600 8000

Time (min)




Weibull model











aa

b

a a aa

b b c

a

ab

bc

b

cb

0

20

40

60

80

Fresh


alowast

blowast

Llowast

NEBΔE










920

930

940

950

960

970

980

990

1000

WHCRR

ba

c

ba

g w

ater

)W

HC

(g re

tain

ed w

ater

100

ab

40 60 80(∘C)

000

020

040

060

080

100

120

140

RR (g

abso

rbed

wat

erg

dm

)




5 Conclusion




Nomenclature




Greek Letters


Subscripts




Acknowledgments


References





































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018



MR = 119872119905119872119900 =81205872 exp(

119863119908119890120587211990541198712 ) (2)

SR = 119878119905119878119900 =81205872 exp(

119863119904119890120587211990541198712 ) (3)


119863119890 = 119863119900exp(minus119864119886119877119879 ) (4)


MRorSR = exp(minus[ 119905120573])120572 (5)















SSE = 1119873infinsum119894=0
















MR

s (di

men

sionl

ess)

MR

w (d

imen

sionl

ess)


600

1100

1600

2100

2600

030

040

050

060

070

080

090

100

100 200 300 4000Time (min)





000010020030040050060070080090100

Moi

sture

ratio

(MR)

200 400 600 8000

Time (min)




Weibull model











aa

b

a a aa

b b c

a

ab

bc

b

cb

0

20

40

60

80

Fresh


alowast

blowast

Llowast

NEBΔE










920

930

940

950

960

970

980

990

1000

WHCRR

ba

c

ba

g w

ater

)W

HC

(g re

tain

ed w

ater

100

ab

40 60 80(∘C)

000

020

040

060

080

100

120

140

RR (g

abso

rbed

wat

erg

dm

)




5 Conclusion




Nomenclature




Greek Letters


Subscripts




Acknowledgments


References





































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018





SSE = 1119873infinsum119894=0
















MR

s (di

men

sionl

ess)

MR

w (d

imen

sionl

ess)


600

1100

1600

2100

2600

030

040

050

060

070

080

090

100

100 200 300 4000Time (min)





000010020030040050060070080090100

Moi

sture

ratio

(MR)

200 400 600 8000

Time (min)




Weibull model











aa

b

a a aa

b b c

a

ab

bc

b

cb

0

20

40

60

80

Fresh


alowast

blowast

Llowast

NEBΔE










920

930

940

950

960

970

980

990

1000

WHCRR

ba

c

ba

g w

ater

)W

HC

(g re

tain

ed w

ater

100

ab

40 60 80(∘C)

000

020

040

060

080

100

120

140

RR (g

abso

rbed

wat

erg

dm

)




5 Conclusion




Nomenclature




Greek Letters


Subscripts




Acknowledgments


References





































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018







MR

s (di

men

sionl

ess)

MR

w (d

imen

sionl

ess)


600

1100

1600

2100

2600

030

040

050

060

070

080

090

100

100 200 300 4000Time (min)





000010020030040050060070080090100

Moi

sture

ratio

(MR)

200 400 600 8000

Time (min)




Weibull model











aa

b

a a aa

b b c

a

ab

bc

b

cb

0

20

40

60

80

Fresh


alowast

blowast

Llowast

NEBΔE










920

930

940

950

960

970

980

990

1000

WHCRR

ba

c

ba

g w

ater

)W

HC

(g re

tain

ed w

ater

100

ab

40 60 80(∘C)

000

020

040

060

080

100

120

140

RR (g

abso

rbed

wat

erg

dm

)




5 Conclusion




Nomenclature




Greek Letters


Subscripts




Acknowledgments


References





































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018









aa

b

a a aa

b b c

a

ab

bc

b

cb

0

20

40

60

80

Fresh


alowast

blowast

Llowast

NEBΔE










920

930

940

950

960

970

980

990

1000

WHCRR

ba

c

ba

g w

ater

)W

HC

(g re

tain

ed w

ater

100

ab

40 60 80(∘C)

000

020

040

060

080

100

120

140

RR (g

abso

rbed

wat

erg

dm

)




5 Conclusion




Nomenclature




Greek Letters


Subscripts




Acknowledgments


References





































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018








920

930

940

950

960

970

980

990

1000

WHCRR

ba

c

ba

g w

ater

)W

HC

(g re

tain

ed w

ater

100

ab

40 60 80(∘C)

000

020

040

060

080

100

120

140

RR (g

abso

rbed

wat

erg

dm

)




5 Conclusion




Nomenclature




Greek Letters


Subscripts




Acknowledgments


References





































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018




Nomenclature




Greek Letters


Subscripts




Acknowledgments


References





































































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018



























































Volume 2018

Zoology











Volume 2018

















Advances in




Enzyme Research





Volume 2018


convective drying of osmo-treated abalone (haliotis...

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