asgment mcrob group farah apc

8/3/2019 Asgment Mcrob Group Farah Apc

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AEROBIC PLATECOUNT

NURFARAH ATIQAHBT ZULKAFLI

02DTM10F2067NOR AKMALIAH BT

MISPAN

02DTM10F2082

ASSIGNMENTMICROBIOLOGY


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The aerobic plate count (APC) is intended to indicate the level ofmicroorganism in a product. Detailed procedures for determining the APC offoods have been developed by the Association of Official Analytical Chemists

(AOAC) and the American Public Health Association (APHA) (1). Theconventional plate count method for examining frozen, chilled, precooked, orprepared foods, outlined below, conforms to AOAC Official Methods ofAnalysis, sec. 966.23, with one procedural change (966.23C). The suitablecolony counting range is 25-250. The automated spiral plate count method forthe examination of foods and cosmetics , outlined below, conforms to AOAC

Official Methods of Analysis, sec. 977.27. For procedural details of thestandard plate count, see ref. 2.Guidelines for calculating and reporting platecounts have been changed to conform with the anticipated changes in the16th edition of Standard Methods for the Examination of Dair.y Productsand the International Dairy Federation (IDF) procedures

INTRODUCTION OF APC


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Level table with ample surface in room that is clean, well-lighted (100 foot-candles at working surface) and well-ventilated, and reasonably free of dustand drafts. The microbial density of air in working area, measured in fallout

pour plates taken during plating, should not exceed 15 colonies/plate during15 min exposure.

Storage space, free of dust and insects and adequate for protection ofequipment and supplies

Petri dishes, glass or plastic (at least 15 x 90 mm)

METHOD OF APC


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Pipets with pipet aids (no mouth pipetting) or pipettors, 1, 5, and 10 ml, graduated in0.1 ml units

Dilution bottles, 6 oz (160 ml), borosilicate-resistant glass, with rubber stoppers or

plastic screw caps

Pipet and petri dish containers, adequate for protection

Circulating water bath, for tempering agar, thermostatically controlled to 45 1C

Incubator, 35 1C; milk, 32 1C

Colony counter, dark-field, Quebec, or equivalent, with suitable light source and gridplate. plate


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Tally register

Dilution blanks, 90 1 ml Butterfield's phosphate-buffered dilution water (R11); milk,99 2 ml

Plate count agar(standard methods) (M124)

Refrigerator, to cool and maintain samples at 0-5C; milk, 0-4.4C

Freezer, to maintain frozen samples from -15 to -20C

Thermometers (mercury) appropriate range; accuracy checked with a thermometercertified by the National Institute of Standards and Technology (NIST)


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The aerobic plate counts ranged from 3.0log to 7.6log 0 CFU/g and 2.1log to 9.7logCFU/g on mixed vegetables and green beans, respectively , as seen table 2 and 3.The

highest proportion of samples (26.1%) fell in the range between 3log and 4log CFU/g

(table 1)

Table 1

Table 2

RESULTS

n ND 10^10-


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Microorganism Number of samples analyed Number ofpositive samples Incidence (%) Mean (log^10CFU/g) Range (log^10CFU/)

Aerobic plate counts @ 30C 100 97 97.0 5.0 2.1-9.7

TABLE 3


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The result for Aerobic Plate Count in our journal same goes to whatJays.J.M(2005)

says in his jurnal:

For the result in our journal write that the fresh cut organic vegetableand green beans with his journal almost same and not more different.

Number of bacteria that have been reported for a number of differentfresh vegetable are summarize in table 1,2 and 3.it maybe noted thatAPCs of around 6 to 7 log10 cfu/gram are common among thevegetable listed and that coliform number around 5-6 log10 areuncommon

The aerobic plate count (APC) measures only that fraction of thebacterial flora that is able to grow to visible colonies under the arbitrarytest conditions provided in the time period allowed

DISCUSSION


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It does not measure the total bacterial population in a food sample, but is thebest estimate.

Altering conditions, such as composition of the agar medium or temperatureof incubation, changes the spectrum of organisms that will grow

It is necessary to adhere rigidly to the standardized test conditions that haveencouraged some to call the APC a "standard plate count.

Depending on the circumstances, a high APC may indicate that a food hasbeen grossly mishandled or that it contains a poor quality ingredient.

Interpretation depends on knowing what the normal APC is for this food.An abnormal APC indicates that something is out of control.


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The microbiologist can frequently suggest that cause, thereby aiding thesanitarian. Some of the problems that investigation of a high APC mightreveal include:

Failure of sorting, trimming, washing, and destroying operations to removeor destroy bacteria from raw ingredients adequately.

Inadequate heat processing.

Insanitary equipment, particularly near the end of the process.

The food has reached or is approaching the end of its refrigerated shelf-life.The food has been stored at or above room temperature for too long.

The food is at least partly decomposed.


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http://aggie-horticulture.tamu.edu/commercial/food_processor/microbio.html

http://www.springerlink.com/content/l0p0501k53721474/

http://books.google.com/books?id=C0sO1gNFWLAC&pg=PA126&dq=aerobic+plate+count+in+vegetable+and+green+beans&hl=en&ei=xGqpTqbqCMHnrAeS0uyODA&sa=X&oi=book_result&ct=result&resnum=2&ved=0CDYQ6AEwAQ#v=onepage&q=aerobic%20plate%20count%20in%20vegetable%20and%20green%20beans&f=false

REFERENCES


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THE ENDS

asgment mcrob group farah apc

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