43.1.14AOAC Of fi cial Method 962.17

Vol a tile Oil in SpicesFirst Ac tion 1962Fi nal Ac tion 1965

Re vised First Ac tion 1996

A. Prin ci pleTest portion is boiled in H2O or NaCl so lu tion. Re leased vol a tile

oil (va por form) is con densed and col lected in trap, and thenmea sured through trap cal i bra tion.

B. Ap pa ra tus(a) Vol a tile oil trap.5 mL, with out stop cock, or dis till ing

re ceiv ers crank case oil, ASTM, 5.0 0.1 mL sub di vi sions (seeFig ure 962.17). Avail able from Wilmad Labglass (Part No. LX4448-1002; 1002 Harding Hwy, Buena, NJ 08310-0688, USA).Once a year cal i brate trap for xylene re ten tion by run ning 3 blanks.Use av er age vol ume.

(b) West con denser.400 mm long with drip tip and stan dardtaper 24/40 ground joints.

(c) Cen trif u gal grind ing mill.Set with 0.75 mm mill screen.Cold grinder can be used. (Note: To pre serve vol a tile oilcon stit u ents, it is crit i cal that mill does not gen er ate heat dur inggrind ing of test sam ple.)

(d) Erlenmeyer flask.2 L; equipped with stan dard taper 24/40ground joint.

(e) Stirring hot plate.Suit able for 2 L flask with vari ablevolt age trans former.

(f) Stirring bars.Tef lon-coated, egg-shaped.(g) Pipet filler.(h) Cyl in der.2 L, grad u ated.(i) Tubing.Tygon tub ing Norton, 79 mm id, or equiv a lent.(j) Re frig er ated cir cu lat ing bath.Main tain ing 20C.(k) In su lating tape.(l) Blender.

C. Re agents(a) Xylene.Re agent grade.(b) So dium chlo ride (NaCl) so lu tion.10% (w/v).(c ) Anti foam B.Sil i cone emul s ion con tain ing 1%

hy dro ge nated tal low gly cer ides (Dow Corning or equiv a lent).(d) Liq uid glassware cleaner.Such as Fisherbrand

Versa-Clean Concentrate.

D. De ter mi na tion Weigh 200 g test por tion. Crack gin ger and tur meric be fore

grind ing. Set grinder with 0.75 mm mill screen. More than 99% must pass through 0.85 mm sieve dur ing the first run. Regrind over sizeun til test por tion passes sieve.

Mix ground material thor oughly and store in re frig er a tor(26C) in tightly sealed con tainer un til anal y sis.

Clean vol a tile oil trap by soak ing over night in liquid glasswarecleaner so lu tion, C(d). Rinse with tap water. Check clean li ness oftrap by add ing small vol ume of dis tilled water. Wa ter should flowdown the wall of trap smoothly. Oth er wise, re peat clean ingpro ce dure.

Be fore re mov ing test por tion for anal y sis, mix ground material incon tainer by ro tat ing, to avoid strat i fi ca tion. Al low test sam ple toequilibrate to am bi ent tem per a ture.

Weigh test por tion as spec i fied in Ta ble 962.17. Quan ti ta tivelytrans fer test por tion to 2 L Erlenmeyer flask. Add ca 1200 mL H2O or NaCl so lu tion, C(b), (see Ta ble 962.17 for dis til la tion sol vent) andadd 23 drops of antifoam. In sert stir ring bar.

Be fore plac ing vol a tile oil trap on flask, en sure that trap is clean.Place trap on flask us ing small amount of non-volatile stop cockgrease on ground joints. Fill col lec tion arms with H2O or NaClso lu tion as spec i fied in Ta ble 962.17. {Note: For all spice, an ise, andcloves add trap ad di tive to grad u ated por tion (see Ta ble 962.17).Add 2 mL xylene us ing 5 mL pipet and ver ify added vol ume us ingvol a tile oil trap cal i bra tion [see B(a)]. Re peat anal y sis if part ofxylene passes back into flask dur ing dis til la tion.}

Con nect trap to con denser us ing small amount of nonvolatilestop cock grease and con nect con denser to re frig er atedcir cu lat ing bath set at 20C. In su late neck of trap and flask within su lat ing tape.

Heat flask on stir ring hot plate with con stant stir ring. Ad justtrap and con denser so that drops flow down the wall of trap and do not drop di rectly on sur face of liq uid. Gently swirl flask sev eraltimes dur ing ini tial heat ing un til test por tion is at roll ing boil toelim i nate scorch ing of test por tion on walls. Main tain re flux rateof 515 drops/10 s. Dis till 8 h or un til 2 con sec u tive read ingstaken at 1 h in ter vals show no change of oil vol ume in trap. Ifsep a ra tion of oil is not sat is fac tory, add 12 drops of dishwashingliq uid to trap through con denser or 23 mL sat u rated NaClso lu tion.

Cool to 20C ei ther by al low ing trap to stand at am bi enttem per a ture or by im mers ing in water bath. If trap is read at

2005 AOAC IN TER NA TIONAL

Figure 962.17. Ap pa ra tus for vol a tile oil in spices.2006 AOAC INTERNATIONAL

tem per a ture other than 20C, in clude it in re port. Read vol ume of oilcol lected to the near est 0.01 mL.

E. Cal cu la tionsCal cu late con cen tra tion of vol a tile oil, % (v/w), in test por tion as

fol lows:

Vol a tile oil, % (v/w) = (Vo/Ws) 100

where Vo = vol ume of oil col lected in trap, mL; and Ws = weight oftest por tion, g.

When us ing 2 mL xylene (Vx) as trap ad di tive, cal cu latecon cen tra tion of vol a tile oil, % (v/w), in test sam ple as fol lows:

Vol a tile oil, % (v/w) = [(Vo Vx)/Ws] 100

where Vx = vol ume of re sid ual xylene, mL.

Ref er ences: JAOAC 17, 70, 371(1934); 18, 611(1935);21, 435(1938); 22, 598(1939); 25, 700(1942);33, 575(1950); 36, 752(1953); 37, 390(1954);38, 548(1955); 42, 312(1959); 45, 212(1962).

F. Spe cific Grav ity of Vol a tile OilDe ter mine spe cific grav ity at 25/25C as in 948.22 (see 40.1.05)

and 950.48 (see 40.1.06), us ing 1 mL Sprengel tube.

G. Re frac tive In dex of Vol a tile OilSee 950.50 (see 40.1.09) and 950.51 (see 40.1.10).

H. Eugenol in Vol a tile Oil (Fi nal Ac tion 1965)Mea sure 2 mL vol a tile oil (trans fer pipet) into Bab cock milk

bot tle, 989.04C(a) (see 33.2.27). Add 20 mL 3% KOH so lu tion(w/v), shake mix ture 5 min, heat 10 min in boil ing water bath,re move, and cool to room tem per a ture. When liq uids sep a ratecom pletely, add enough KOH so lu tion to bring re sid ual oil withingrad u ated por tion of neck and note vol ume. Cal cu late % by vol umefrom dif fer ence be tween vol ume of test portion used and re sid ualoil.

CAS-97-53-0 (eugenol)

I. Vol a tile Oil and Resin in Gin ger (Fi nal Ac tion 1965)Place 50 g ground gin ger in Soxh let ex trac tor and ex tract

com pletely with ether (ca 4 h). Trans fer ex tract to 300 mL flask andevap o rate ether on steam bath un til sol vent is no lon ger de tected. Add50 mL H2O to res i due and de ter mine yield of vol a tile oil (us ing trapfor oils lighter than H2O), spe cific grav ity, and re frac tive in dex, as inDG.

Trans fer res i due in flask to sep a ra tor and ex tract resin with ether.Trans fer to tared beaker, evap o rate ether on steam bath, and dry tocon stant weight in vac uum des ic ca tor.

Ref er ence: JAOAC 19, 98, 411(1936).

Re vised: March 1998

2005 AOAC IN TER NA TIONAL

Ta ble 962.17. Weights, dis til la tion sol vents, and trapad di tives for var i ous spices

SpiceTest portion

weight, gDis til la tion

sol ventTrap

ad di tive

Allspice 4010% NaClso lu tion

Xylene,2.0 mL

An ise 5010% NaClso lu tion

Xylene,2.0 mL

Ba sil 50 H2O Bay leaves 60 H2O Car a way 50 H2O Cardamon 50 H2O Cel ery seed 50 H2O

Cloves 1010% NaClso lu tion

Xylene,2.0 mL

Co ri an der 70 H2O Cumin 50 H2O Dill seed 50 H2O Fen nel 50 H2O Fenu greek 50 H2O

Gin ger 5010% NaClso lu tion

Mar jo ram 40 H2O Nut meg 30 H2O Mace 20 H2O Oreg ano 40 H2O Black pep per 50 H2O White pep per 40 H2O Rose mary 50 H2O Sage 50 H2O Sa vory 40 H2O Tar ra gon 40 H2O Thyme 50 H2O Tur meric 50 H2O

2006 AOAC INTERNATIONAL