AOAC 15.1.04 AOAC Official Method 998.10 Efficacy of Preservation-国外标准规范
AOAC脂肪提取标准
39.1.08AOAC Official Method 991.36 Fat (Crude) in Meat and Meat ProductsSolvent Extraction (Submersion) MethodFirst Action 1991Final Action 1996[Applicable to meat and meat food products that can be analyzed using 960.39 (see 39.1.05), 976.21 (see 39.1.06), and 985.15 (see39.1.07).]Results of the interlaboratory study supporting acceptance of the method:x—, 4.34% fat: s r= 0.106; s R = 0.112; RSD r= 2.44%; RSD R = 2.59%x—, 27.29% fat: s r= 0.534; s R = 0.637; RSD r= 1.95%; RSD R = 2.33%x—, 27.95% fat: s r= 0.648; s R = 0.739; RSD r= 2.32%; RSD R = 2.84%x—, 34.51% fat: s r= 0.764; s R = 0.799; RSD r= 2.21%; RSD R = 2.31%x—, 33.57% fat: s r= 0.340; s R = 0.516; RSD r= 1.01%; RSD R = 1.53%x—, 26.20% fat: s r= 0.406; s R = 0.631; RSD r= 1.55%; RSD R = 2.34%A. Apparatus装置(a) Extraction system.—Capable of simultaneous extraction of 6 test portions. Extraction unit for solvent addition to cups, 2-stage extraction process, and solvent recovery cycle. Service unit to supply hot oil through insulated tubing to extraction unit and to pump air for evaporation of last traces of solvent from cups (Soxtec System meets these specifications).(b) Thimbles and stand.—26 *60 mm, cellulose thimbles, and stand to hold 6 thimbles.(c) Extraction cups.—Al, 44 id, 60 mm height.(d) Glass beads.—3–4 mm diameter.(e) Mechanical convection oven. — Maintaining 125° ± 1°C.Items (a)–(c) are available as Soxtec sys tem from Perstorp Analytical/Tecator, Inc. (2875 C Towerview Rd, Herndon, V A 22071, USA).B. Reagents(a) Petroleum ether. — To meet specifications in 945.16A (see 27.4.04).(b) Sand.—<0.004 g extractables/5 g.(c) Cotton.—Defatted.C. DeterminationAccurately weigh ca 3 g test portion into thimble. Add sand to test portion and mix with glass rod. Place thimble in thimble stand and dry 1 h in 125°C oven. Remove from oven and let cool. Loosen test portion/sand mixture using glass rod. Wipe glass rod with small amount of cotton and place cotton in top of thimble. Transfer thimble to extraction unit. Accurately weigh extraction cup containing a few glass beads.Extract thimble with dried mixture with 40 mL petroleum ether in boiling position for 25 min and in rinsing position for 30 min. Adjust temperature of extraction unit to ensure condensation rate≥5 drops/s. At completion of extraction, close condenser valves and recover ether.Dry cup and contents 30 min in 125°C oven. Cool and weigh.D. CalculationsCalculate percent fat in test sample as follows:Fat content, % = (B -C) *100Awhere A = g test portion weight, B = g weight of extraction cup afterdrying, and C = g weight of extraction cup prior to extraction.Reference: J. AOAC Int. 75, 289(1992).39.1.07AOAC Official Method 985.15Fat (Crude) in Meat and Poultry 家禽Products Rapid Microwave-Solvent Extraction Method First Action 1985Final Action 1991A. Reagents and Apparatus(a) Automated solvent extractor.—Enclosed, self-contained, thermostatically controlled 恒温控制fat extraction and solvent recovery system with 0.5 mg fat sensitivity and 0–100% fat measurement range (CEM Corp., PO Box 200, Matthews, NC 28106, USA), or equivalent.(b) Methylene chloride.二氯甲烷—Reagent grade (Fisher Scientific Co., No. D-37) , or equivalent.(c) Glass fiber pads.玻璃纤维垫子—9.8 *10.2 cm rectangular 矩形and 11 cm round (CEM Corp.), or equivalent.(d) Microwave moisture analyzer.—0.2 mg H2O sensitivity, moisture/solids range of 0.1–99.9%,0.01% resolution分辨率. Includes automatic tare electronic balance, microwave drying system，and microprocessor digital computer control. Electronic balance pan is located inside drying chamber. (Balance sensitivity: 0.2 mg at 15 g capacity or 1.0 mg at 40 g capacity [CEM Corp., or equivalent].)B. DeterminationPrepare test samples as in 983.18 (see 39.1.01). Place 2 rectangular and one round glass fiber pad on balance pan inside microwave moisture analyzer, and tare. Remove rectangular pads and evenly spread ca 4 g well-mixed test portion onto rough side of one pad, cover with second pad, and place together with round pad on balance pan. Dry 3–5 min at 80–100% power, depending on product type. At end of drying cycle, remove from balance pan. Fold rectangular pads, with dried test portion, in half and place in automated solvent extractor chamber. Place round pad in recessed area at top of extractor chamber, close and latch lid. Start extraction cycle (test portion and rectangular pads are blended at this time with sufficient CH2Cl2to extract fat). After completion of extraction cycle, remove round pad with residue, and place on balance pan in microwave moisture analyzer. Redry pad and residue to constant weight (ca 30 s at 80–100% power) to re move residual solvent or moisture. Weight loss due to solvent extraction is converted to % fat by microprocessor and displayed on digital read out panel.Certain product classes require addition of adjustment factors to read out for accurate results, as follows: fresh meats, pre-blends, emulsions, cured/cooked meats, factor = 0.40; cooked sausages, factor = 0.80.Reference: JAOAC 68, 876(1985).39.1.06AOAC Official Method 976.21Fat (Crude) in Meat Rapid Specific Gravity MethodFirst Action 1976Final Action 1979A. Apparatus and Reagents(a) Foss-let fat analyzer.—Includes orbital shaker, specific gravity readout unit, solvent dispenser, reference standard oil (specific gravity at 23°C = 0.915; for periodic check of potentiometer calibration), stainless steel cup with cover and 8 mm bore brass hammer, pressure filtration device, and conversion chart (Foss Food Technology Corp.).(b) Drying agent.—Plaster of Paris (available locally through paint, hardware, or building supply dealers), 8 mesh Drierite, or an hydrous CaSO4.(c) Tetrachloroethylene.—Technical grade C2Cl4 (distributed locally through dry cleaning sup pliers or Fisher Scientific Co.,No. C-182).B. Deter mi na tionPrepare test sam ples as in 983.18 (see 39.1.01). Check calibration of Foss-let potentiometer daily by us ing C2Cl4 alone to set zero point.Use mixture of 22.5 g reference standard oil and 120 mL C2Cl4(specific gravity of mixture at 37° = 1.4763) to set 50% fat point at 850.0.Using either top-load or triple-beam balance with 0.1 g sensitivity, tare Foss-let cup after setting brass ham mer on itsspin dle. To an a lyze prod ucts con tain ing £60% fat, weigh 45.0 gtest sam ple into cup; for prod ucts con tain ing >60% fat, weigh22.5 g. Add ca 80 g Plas ter of Paris (or ca 60 g an hy drous CaSO4).Dis pense 120 mL C2Cl4 into cup. Press cover onto cup and in stall inor bital shaker. Set shaker timer for 2 min and turn unit on. Whileex trac tion pro ceeds, as sem ble pres sure fil tra tion de vice by plac inginto per fo rated base 7 cm fil ter pa per. To pro duce clear fil trate freeof mois ture drop lets (for very wet test sam ples), first place highre ten tion pa per, Whatman No. 50, or equiv a lent, and then phasesep a rat ing pa per, Whatman No. 1PS, or equiv a lent. Af ter 2 minex trac tion, re move cup from shaker, lift cover, and re move brassham mer from cup. Im merse cup in ice-water bath ca 0.4 min whilestir ring con tents with ther mom e ter to cool con tents from 47°–52°Cto ca 40°C. Wipe H2O from outer sur face of cup and pour con tentsinto as sem bled fil ter. Place pis ton at top of fil tra tion de vice andslowly press ex tract through mea sur ing sys tem. De press drain valvebut ton when ex tract ap pears in over flow tube and let cham ber drain;then re lease valve but ton. Re peat fill ing and drain ing 2 more timesun til 40–50 mL ex tract has flowed through, re tain ing fi nal 10 mLex tract in mea sur ing cham ber. Re move fil tra tion de vice, slideview ing lens into po si tion, ro tate con trol of read out po ten ti om e terclock wise un til hy drom e ter rises, and re cord read ing. Es tab lish thatex tract is at cham ber tem per a ture by re peat ing read ing 3–4 times.Av er age read ings and con vert into % fat by means of con ver sion chart. (Mul ti ply chart % fat by 2 if a 22.5 g por tion of high-fat product was used.)Ref er ences: JAOAC 58, 1182(1975); 60, 853(1977);68, 240(1985).。
微波,核磁共振法 水分,固形物,脂肪 快速测定仪 AOAC标准操作规程
食品与食品添加剂
JOURNAL OF AOAC INTERNATIONAL VOL. 88, NO. 1, 2005
提示安装心脏起搏器或其他磁干扰仪器的人员与SMART Trac仪器磁元 件保持至少11英寸（0.3米）的距离。 2 本方法利用微波干燥法和快速NMR测定法来测定水分/固形物和脂肪含量， 特别是乳制品。本方法适用于大部分乳制品，测定范围宽泛。
5.缩写与专业术语 5.1 5.2 5.3 5.4 NMR——核磁共振 RF——随机频率 NCSU——北卡罗来州立大学 NIR——近红外
食品与食品添加剂
JOURNAL OF AOAC INTERNATIONAL VOL. 88, NO. 1, 2005
5.5 5.6
LR-NMR——低场核磁共振检测 DQCI——奶制品质量控制协会
6 方法原理 在上世纪中叶，人们开始探索NMR技术。通过观察静态磁场下，脉冲频率 使原子核吸收和释放随机频率能量的现象。核同位素发生NMR效应的频率依赖 于磁场的强度。 而这一现象是由原子核偶极磁矩和外加磁场共同影响的（这就是 核磁共振名字的由来，NMR并不涉及电离辐射过程）。 虽然许多元素的原子核都可以发生核磁共振信号，但是人们广泛应用 1H核 进行NMR实验，我们通常称之为“质磁共振”。核磁共振技术用于成像分析已 经有几十年的历史了，衍生出MRI核磁造影技术，MRI用于临床诊断已经超过20 年了。 SMART Trac系统利用NMR技术，LR-NMR测定方法用于工业质量控制也有 超过20年的历史了。大部分的LR-NMR测定法都是用的质磁共振。质磁共振技术 的主要区别于核磁共振的地方在于， 它是通过区别不同状态的氢核的含量来检测 样品成分的。 在核磁共振谱中，我们通过不同分子或相同分子不同部位的 1H核在磁场作 用下发生能量变化时微小的信号差异来区别不同的物质， 这是由于分子中电子分 布不一样的结构特点决定的，这导致了不同成分各自分子 1H核NMR频率微小的 不同（T2弛豫时间，也就是横向弛豫时间），这一现象导致样品中不同成分NMR 信号不同。这种现象被称之为化学位移效应。
AOAC 官方方法999.03 食品中总果聚糖的测定中文翻译
AOAC 官方方法999.03 食品中总果糖的测定酶/分光光度法1999年第一次执行（适用于食品中果糖的测定。
不适用于高度解聚的果糖，无论是酸的还是酶的。
）支持方法验收的实验室间研究结果见表999.03。
A.原理用热水提取产物以溶解果聚糖。
将等份的提取物用特定的蔗糖酶处理以将蔗糖水解成葡萄糖和果糖，并用纯淀粉降解酶的混合物将淀粉水解成葡萄糖。
所有还原糖用碱性硼氢化物还原成糖醇。
果聚糖用纯化的果聚糖酶（外切-菊粉酶加内切-菊粉酶）水解成果糖和葡萄糖，并且这些糖通过β-羟基苯甲酸酰肼（PAHBAH）方法测量用于还原糖。
B.装置设备（a）研磨机。
（b）热板。
带磁力搅拌器。
（c）水浴.保持40±0.1℃。
（d）沸水浴。
（e）涡旋混合器。
（f）pH计。
（g）停止计时器。
（h）滤纸。
（i）真空烘箱。
用于干燥果糖标准品。
（j）分光光度计。
在410nm下操作。
（k）移液管。
用一次性吸头输送100和200μL。
或者，可以使用机动手持式分液器。
（l）正位移移液器。
（m）玻璃试管。
（n）容量瓶。
（0）聚丙烯容器。
C.试剂所有试剂应具有分析纯度等级。
（a）马来酸钠缓冲液。
100mM。
pH 6.5。
将11.6g马来酸溶于900mL蒸馏水中，用2M NaOH（8.0g NaOH / 100mL）将pH调节至6.5，并用水稀释至体积1L容量瓶中。
储存在4℃。
（b）乙酸钠缓冲液。
100mM。
pH 4.5。
将5.8 mL冰醋酸（1.05 g / mL）吸取到900 mL蒸馏水中。
使用1M NaOH调节至pH 4.5并用水稀释至1L。
储存在4°C。
（c）对羟基苯甲酸酰肼（PAHBAH）还原糖分析试剂.（1）溶液A.-在磁力搅拌器上，在250mL烧杯中加入10g PAHBAH至60mL水中。
搅拌浆液并加入10mL浓HCl。
用蒸馏水调节至200 mL并在室温（约22°C）下储存。
溶液稳定至少2年。
（2）溶液B.-将24.9g柠檬酸三钠二水合物加入500mL蒸馏水中并搅拌溶解。
AOAC官方分析方法 998_09
(4) 培养结束后，用手冲洗孔板，用盛有工作冲洗液的塑料挤瓶， 或装有工作冲洗液的洗液机：
(a) 快速颠倒托盘，将内容物清空入容器内。(b) 将托盘面朝下， 在纸巾上用力敲打数次来移去残留液体。(c) 用工作冲洗液充满每个孔
F. 酶免疫分析
(1) 开始分析前必须制备下述试剂。(a) 在试剂瓶中用蒸馏水或去 离子水将 1 小瓶冲洗液浓缩液稀释至 2 L，以制备工作冲洗液。手工冲 洗托盘时，用塑料挤瓶较理想。(b) 移取 3 mL 对照稀释液至装有冻干 阳性对照抗原的小瓶中制备复原的阳性对照，并充分混合。将剩余的对 照稀释液用作阴性对照。(c) 将小瓶中的接合剂稀释液加入冻干接合剂 中，以制备复原的接合剂。使接合剂室温水解。轻轻地混合复原的接合 剂。(d) 将小瓶中底物稀释液加入冻干的底物中复原底物。确保底物溶 解并且在使用前底物处于室温。复原底物呈淡绿色。(e) 使用可接受的 终止液，无需复原。
穴。(d) 重复(a)-(c)两次以上。 (5) 按照步骤(4)(a)到(b)来清空托盘；然后在每个孔穴中添加 0.2 mL
复原的接合剂。盖好托盘，于 35-37°C 培养 30 min。 (6) 按照步骤(4)(a)到(c)彻底清空托盘内容物 4 次，然后按照步骤
(4)(a)到(b)清空托盘。 (7) 每个孔穴添加 0.2 mL 复原底物。于室温(20-25°C)培养至少 10
G．判读
阳性结果可以按以下方式判读 (1) 参照比色卡用肉眼判读，只有当 阳性和阴性对照符合比色卡指示的颜色时，阳性结果才有效；或者(2) 用仪器法，采用滤光光度计，仅当阴性和阳性结果达到可接受的吸光值 时，阳性结果才有效。 (1) 将托盘置于白色背景下，然后用比色卡比较单个测试孔穴。阳性对 照应该呈现浓的蓝绿色，说明所有试剂是有效的。如果阳性结果比比色 卡上的阳性结果颜色浅，则测试无效；参考包装插件中的“问题解决指 导”。如果阴性对照比比色卡上阴性结果颜色更深，有可能托盘冲洗不 充分，必须重新分析。 (2) 蓝绿色产品的最大吸收值出现在 414 nm。所以，在 414±10 nm 判读 托盘。对于单波长的光度计，将光度计设置为零(空白：孔穴中含有 200 µL 底物或水)。对于双波长光度仪，将光度计设为零(空白：空气)， 并 设置第二参比波长为 490±10 nm。当 A≥0.3 表示结果阳性。阳性对照的 A 值应≥1.0，阴性对照应<0.2。
ColiComplete 产品说明书
Page 1 of 2 ColiComplete ®AOAC Official Method 992.30General DescriptionColiComplete ® contains 5-bromo-4-chloro-3-indolyl-ß-Dgalactopyranoside (X-Gal) and 4-methyl umbelliferyl-ß-D-glucuronide (MUG). Discs are added to LST inoculated with selected dilutions of samples. Samples are incubated at 35–37 °C and examined after 24 and 48 ±2 h for confirmed total coliforms and after 30 ±2 h for confirmed E. coli results. ß-Galactosidase, from coliforms present in samples, cleaves X-Gal into 5-bromo-4-chloro-indoxyl intermediate which undergoes oxidation to yield water-insoluble blue dimer, visually detectable on disc or in surrounding medium as confirmed positive result for total coliform activity. ß-Glucuronidase, from E. coli present in samples, cleaves MUG into glucuronide and methyl umbelliferone which fluoresces under long wave UV light (366 nm) as confirmed positive result for E. coli presence.NOTE : As E. coli O157:H7 does not produce ß-glucuronidase, ColiComplete ® is not suitable for the detection of E. coli O157:H7.A. Sample PreparationPrepare appropriate serial dilutions as indicated in FDA Bacteriological Analytical Manual (BAM), or AOAC Official Methods of Analysis according to sample type.B. InoculationInoculate LST tubes with appropriate sample dilution series selected to determine MPN levels or presence/absence of total coliforms and E. coli in sample. Aseptically add a single ColiComplete ® disc to each tube. Incubate at 35–37 °C.C. Reading ColiComplete ®a. For total coliforms — After at least 24 h incubation, examine each tube for visually detectable blue color on disc or in surrounding medium. Presence of blue color indicates confirmed positive result for total coliforms.NOTE: A wide range of blue color intensity may be expected, depending on sample composition and microflora. All blue reactions are positive regardless of intensity of color.Reincubate at 35–37 °C. After additional 24 ±2 h re-examine. Continued absence of blue indicates negative result; presence of blue indicates confirmed positive result for total coliforms. Read and record the MPN code or presence/absence of total coliforms in the sample.b. For E.coli — After 30 ±2 h from start of initial incubation, examine tubes under long-wave UV light (366 nm). Fluorescent tubes indicate confirmed positive result for E. coli. Read and record the MPN code or presence/absence of E. coli in the sample.D. CONTROLSPositive and negative controls should be used to facilitate interpretation of MUG fluorescent reaction. Use one known positive E. coli tube and two negative controls - one non -E. coli /coliform tube (e.g., Klebsiella spp.) and one uninoculated media tube.NOTE: Use borosilicate glass tubes, flint glass gives fluorescence that may be misinterpreted for a positive result.Lit. No. MK_UG4655EN Merck KGaAFrankfurter Strasse 25064293 DarmstadtGermanyPage 2 of 2 E. Method Modification for Certain JuicesApplicable to juice products/processors which rely on treatments that do not come into direct contact with all parts of the juice, as contained in 21 CFR Part 120: Rules and Regulations. Hazard Analysis and Critical Control Point (HAACP); Procedures for the Safe and Sanitary Processing and Importing of Juice; Final Rule. Vol 66 No. 13. 6137-6202. Use the modified method “Analysis for Escherichia coli in Citrus Juices - Modifi cation of AOAC Official Method 992.30” as stated in Section 120.25 (a).F. StorageStore unused discs at 2–8 °C (36–46 °F) in a sealed container, with desiccant.G. DisposalAfter use, all tubes must be steam-sterilized at 121 °C for at least 30 min before discarding. For in-vitro diagnostic use only.Manufacturing EntityBioControl Systems, Inc, 12822 SE 32nd St, Bellevue, WA 98005, USA.BioControl Systems, Inc is an affiliate of Merck KGaA, Darmstadt, Germany.。
AOAC_Official_Method_995
AOAC Official Method 995.03Capsaicinoids in Capsicums and Their ExtractivesLiquid Chromatographic MethodFirst Action 1995[Applicable for determination of 750-650000 Scoville Heat Units (SHU) of capsaicinoids in ground and crushed red pepper, chili pepper, ground cayenne pepper, ground jalapeno pepper, and red pepper oleoresins. Not applicable to chili powders or products containing oregano or thyme.](Caution: See Appendix B, safety notes for the safe handling of organic solvents and special chemical hazards-acetone, acetonitrile, and ethanol. See Material Safety Data Sheets, or equivalent, for each reagent. N-Vanillyi-nnonanamide is an extreme irritant; do not inhale. Dispose of waste solvents in an appropriate manner compatible with applicable environmental rules and regulations.)Method Performance:See Table 995.03 for method performance data.A. PrincipleTest sample is extracted in warm ethanol using reflux condenser. Extract is filtered and injected into liquid chromatograph equipped with UV or fluorescence detector.B. Apparatus (a) Liquid chromatograph (LC).--Equipped with I V integrator, 20 gL sample injector, and with UV detector set at 280 run. wavelength or fluorometer with excitation 280 nm and emission 325 nm. Operating conditions: temperature, ambient (20-25'C); flow rate, 1.5 mL/min., isocratic; relative retention times: N-vanillyl-n-nonanamide, 1.00; nordihydrocapsaicin, 0.90; capsaicin, 1.00; dihydrocapsaicin, 1.58. See Figure 995.03 for baseline separation of major capsaicinoids.(b) LC column.--Stainless, C18, 150 x 4.6 mm id, packed with 5 micrometer particle size. Use guard column, if desired.(c) Reflux condenser.(d) Syringe filter.- 0.45 micrometer.(e) C18 solid-phase extraction cartridge.C. Reagents(a) Ethanol-95% or denatured, suitable for chromatography(b) Acetone.-ACS grade.(c) LC mobile phase@Acetonitrile-water. Use LC grade solvents, or equivalent. Mix400 mL acetonitrile with 600 mL H20 containing 1% acetic acid (v/v). De-gas with helium or by other suitable technique.(d) N-Vanillyl-n-nonanamide standard solutions. -N-Vanillyln-nonanamide standard, 99%, is available as synthetic capsaicin from Penta International Corp., 50 Okner Pkwy, Livingston, NJ 07039. Keep solutions out of direct sunlight. (1) Standard solution A.-0. 15 mg/mL. Accurately weigh 75 mg N-vanillyl-n-nonanamide and transfer it into 500 mL volumetric flask. Dilute to volume with ethanol, and mix. Use standard solution A for analyzing all peppers except chili pepper.(2) Standard solution B.-0.015 mglmL. Transfer 10 mL standard solution A into I 00 mL volumetric flask, dilute to volume with ethanol, and mix. Use standard solution B when analyzing chili peppers.D. Extraction(a) Ground or crushed peppers.-Accurately weigh ca 25 g pepper into 500 ITIL boiling flask. Place 200 mL ethanol into same flask, add several glass beads, and attach flask to reflux condenser. Gently reflux test sample 5 h and then allow to cool. Filter 1-4 mL sample through 0.45 gm syringe filter into small glass vial. Use for LC analysis.(b) Red pepper oleoresins.-Accurately weigh 1-2 g oleoresin into 50 mL volumetric flask. Increase weight of sample, if total capsaicinoid concentration is < 1 %. Note: Do not allow any oleoresin to coat sides of flask.Add 5 mL acetone, C(b), to flask and swirl contents of flask until test sample is completely dispersed (no oleoresin can coat bottom of flask when turning flask neck at 45' angle). Add five 3-5 mL portions ethanol, swirling flask during each addition. Dilute contents of flask to volume with ethanol and mix well.Figure 995.03-Red pepper extract analyzed by (a) fluorescence detection, and (b) UV detection.Peak 1 = nordihydrocapsaicin; peak 2 = capsaicin; peak 3 = dihydrocapsaicinHold C18 solid-phase extraction cartridge over 25 mL volumetric flask or place cartridge on 10 mL glass syringe and hold over 25 mL volumetric flask. Transfer 5 mL solution from flask to cartridge or syringe. (Note: When using syringe, deliver solution to bottom of syringe so that sides of syringe are not coated with sample.) Pass aliquot through cartridge and collect in 25 mL flask. Wash cartridge 3 times with 5 mL ethanol, collecting washings in same flask. Dilute contents of flask to volume with ethanol and mix. Filter 1-4 mL solution through 0.45 micrometer syringe filter into small glass vial. Use for LC analysis.E. LC DeterminationInject 20 microliters standard solution B, C(d)(2), onto LC column, when analyzing chili peppers. When analyzing other matrices inject 20 microliters standard solution A, C(d)(1). Re-inject standard solution at intervals of 6 sample injections, or less.Inject in duplicate 20 microliter test sample from D onto LC column.After <30 sample injections, purge LC column 30 min with 100% acetonitrile at 1.5 mL/min flow rate. Use LC mobile phase, C(c), for further analysis.F. CalculationCapsaicinoids contain 3 major compounds: nordihydrocapsaicin (N), capsaicin (C), and dihydrocapsaicin (D). Calculate capsaicinoids as sum of these compounds [N + C + D; in Scoville Heat Units (SHU); 1 microgram total capsaicinoids/g = ca 15 SHU], as follows: (a) UV detection(1) Ground peppers and chili pepper.-N = (Pn/Ps) x (Cs/Wt) x (200/0.98) x 9300C = (Pc/Ps) x (Cs/Wt x (200/0.89) x 16100D = (Pd/Ps) x (Cs/Wt) x (200/0.93) x 16100where Pn, Pc, and Pd = average peak areas for nordihydrocapsaicin, capsaicin, and dihydrocapsaicin, respectively, from duplicate injections; Ps = average peak area of appropriate standard solution; Cs = concentration of standard solution, mg/mL; Wt = weight of test sample, g(2) Red pepper oleoresins:N= (Pn/Ps) x (Cs/Wt) x (250/0.98) x 9300C = (Pc/Ps) x (CS/Wt) x (250/0.89) x 16100D = (Pd/Ps) x (CS/Wt) x (250/0.93) x 16100(b) Fluorescence detection (1) Ground peppers and chili pepper.N= (Pn/Ps) x (Cs/Wt) x (200/0.92) x 9300C = (Pc/Ps) x (CS/Wt) x (200/0.88) x 16100D = (Pd/Ps) x (CS/Wt) x (200/0.93) x 16100(2) Red pepper oleoresins:N= (Pn/Ps) x (Cs/Wt) x (250/0.92) x 9300C = (Pc/Ps) x (CS/Wt) x (250/0.88) x 16100D = (Pd/Ps) x (CS/Wt) x (250/0.93) x 16100Reference: J. AOAC Int. (future issue).(c) 1996 AOAC INTERNATIONAL。
AOAC 980.13
31.5.04AOAC Official Method980.13Fructose,Glucose,Lactose,Maltose,and Sucrose in Milk ChocolateLiquid Chromatographic MethodFirst Action1980Final ActionA.Apparatus(a)Liquid chromatograph.—With Waters Associates,Inc. M6000A pump,R401refractive index detector,or equivalent,and 10mV recorder.(b)Column packing.—Waters Associates,Inc.µ-Bondapak car-bohydrate column,300×4(id)mm.Column must meet following criteria:Capacity factor for fructose=K′=(t R−t0)/t0≥5where t R=retention time for fructose=time from injection to maxi-mum peak height of fructose;t0=retention time for solvent=time from injection to maximum peak height of first baseline distortion or solvent peak.Resolution factor(distance between2band centers divided by av-erage band width)=R s=(t2-t1)/0.5(t w1+t w2)where t2and t1=times from injection to maximum peak heights of second peak(glucose)and first peak(fructose),respectively;and t w1 and t w2=baseline widths(in time units)of first and second peaks,re-spectively.For fructose:glucose ratios of2.0–0.5,R s≥1.0;for ratios ≥2,R s≥1.25.Replace column when either or both criteria are not met.(c)Injection valve.—Waters Associates,Inc.7120LC injector with50µL loop,or equivalent.(d)Ancillary equipment.—Bransonic12ultrasonic bath (Branson Ultrasonics Corp.,Eagle Rd,Danbury CT06810-1961, USA,No.B1210MT),or equivalent,to degas solvents;Corning PC353stirrer(replaced by PC510);and filtration apparatus for solvent purification.B.Reagents(a)Sugar standard solution.—10µg/mL.Dry individual sugar standards(fructose,glucose,sucrose,lactose,and maltose;available from Sigma Chemical Co.)12h at60°C under vacuum.Dissolve in H2O and serially dilute to concentration of10µg/mL.Prepare daily.(b)Mobile phase.—CH3CN(No.2442,Mallinckrodt Nanograde,or equivalent)+H2O(charcoal filtered)(80+20).Filter through Whatman GF/F0.7µm glass fiber filter,and degas in ultra-sonic bath before use.C.Preparation of Test SampleWeigh10.0g finely divided milk chocolate into≥100mL centri-fuge bottle and add50mL petroleum ether.Centrifuge ca15min at ca1800rpm.Decant and discard supernate.Repeat extraction. Pulverize residue with glass rod,add100g H2O,and weigh. Place in85–90°C H2O bath25min.Cool to room temperature and add H2O to original weight.Centrifuge10min at2000rpm,with-draw portion of clear supernate,and filter through0.45µm Swinney syringe filter.D.DeterminationFill50µL injection loop with test sample solution and inject into col-umn with mobile solvent flowing at1.5–2.0mL/min.Calculate concen-trations of each sugar by comparing peak heights or areas of each sugar peak from test sample with corresponding height or area of standard. Use same method of measurement(area or height)throughout. Reference:JAOAC63,595(1980).CAS-57-48-7(fructose)CAS-50-99-7(glucose)CAS-63-42-3(lactose)CAS-69-79-4(maltose)CAS-57-50-1(sucrose)©2000AOAC INTERNATIONAL。
膳食纤维 标准方法
膳食纤维标准方法
膳食纤维是指人体无法消化吸收的碳水化合物类物质。
膳食纤维对人体健康具有重要的作用，包括促进消化系统健康、调节血糖和胆固醇水平、预防便秘以及控制体重等。
为了准确测量食物中的膳食纤维含量，需要进行标准方法的测定。
目前，国际通用的膳食纤维含量测定方法有两种：AOAC （Association of Official Analytical Chemists）方法和ISO （International Organization for Standardization）方法。
1. AOAC方法：AOAC方法是美国官方方法，也是国际上最常用的方法。
根据AOAC 991.43或AOAC 985.29方法，首先将食物样品经过一系列处理，如酶解、水解等，获得可溶性和不可溶性纤维。
然后，借助酶解、滴定、重量等技术手段，可以得到总纤维、不可溶性纤维和可溶性纤维的含量。
2. ISO方法：ISO方法是由国际标准化组织制定的方法，与AOAC方法相似。
ISO 13904和ISO 15954方法是常用的ISO 方法。
这些方法主要利用酶解、水解、甲弹法等技术，将膳食纤维分为不可溶性纤维和可溶性纤维，并使用滴定、重量等手段进行测定。
无论使用AOAC方法还是ISO方法，都需要进行样品的预处理、酶解、滴定等步骤，以获得准确的膳食纤维含量。
这些方法在实验室条件下进行，需要仪器设备和专业操作人员进行操作。
需要注意的是，虽然AOAC和ISO方法都是国际通用的标准方法，但在具体的实验操作过程中，可能会存在一些差异，因此在测定过程中应当依据相应的方法详细操作，并遵循实验室的操作规程。
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15.1.04AOAC Official Method998.10Efficacy of Preservationof Non-Eye Area Water-Miscible Cosmeticand Toiletry FormulationsFirst Action1998Caution:A knowledge of microbiological techniques is required for these procedures.Follow general aseptic and safetyprocedures(1).See Table998.10for the results of the interlaboratory study sup-porting the acceptance of the method.A.PrincipleBacteria,yeast,and mold are grown on laboratory media,har-vested,calibrated,and inoculated into test ing serial di-lutions and plate counts,the numbers of organisms surviving in the test products are determined over time.Products meeting the speci-fied criteria are considered adequately preserved for manufacture and consumer use.Products not meeting criteria are considered in-adequately preserved.B.Apparatus(a)Jars.—2–4oz.wide-mouth,straight-side flint glass ointment jars with linerless metal,polypropylene or Teflon®lined screw caps.(b)Disposable borosilicate glass culture tubes.—16×125mm, with caps.(c)Disposable borosilicate glass culture tubes.—20×150mm, with screw caps.(d)Petri plates.—100×15mm.(e)Sterile2.2mL pipets.(f)Sterile swabs.(g)Glass beads.(h)Sterile gauze.(i)10–20µL inoculating loops.(j)Vortex mixer.C.ReagentsFor convenience,dehydrated media of any brand equivalent in function may be used.Test each lot of medium for sterility and growth-promotion using suitable organisms.(a)Letheen agar.—Contains5.0g pancreatic digest of casein,1.0g dextrose,3.0g beef extract,1.0g lecithin,7.0g polysorbate80, and15.0g agar per L.Prepare according to manufacturer’s directions. Dispense into suitable containers and sterilize by autoclaving at 121E C for15min.Final pH should be7.0±0.2at25E C.Place in45E C water bath until agar is45±2E e for pour plates.(b)D/E neutralizing broth(Dey/Engley).—Contains5.0g pan-creatic digest of casein,2.5g yeast extract,10g dextrose,1.0g so-dium thioglycollate,6.0g Na2S2O3⋅5H2O,2.5g NaHSO3,7.0g lecithin,5.0g polysorbate80,and0.02g bromcresol purple per L. Prepare according to manufacturer’s directions.Dispense9or 9.9mL aliquot into tubes and sterilize by autoclaving at121E C for 15min.Final pH should be7.6±0.2at25E e for aerobic plate count,L,dilutions.(c)Nutrient agar.—Contains5.0g pancreatic digest of gelatin,3.0g beef extract,and15.0g agar per L.Prepare according to manu-facturer’s directions.Dispense into tubes and sterilize by autoclaving at121E C for15min.Final pH should be6.8±0.2at 25E C.Cool in inclined position to form a e for bacterial cul-ture maintenance and inoculum preparation.(d)Y/M agar(yeast/malt extract).—Contains3.0g yeast extract,3.0g malt extract,5.0g peptone,10.0g dextrose,and20.0g agar per L.Prepare according to manufacturer’s directions.Dispense into tubes and sterilize by autoclaving at121E C for15min.Final pH should be6.2±0.2at25E C.Cool in slanted e for yeast culture maintenance and inoculum preparation.(e)Potato dextrose agar(PDA).—Contains200g potato infu-sion,20.0g dextrose,and15.0g agar per L.Prepare according to manufacturer’s directions.Dispense into tubes and sterilize by autoclaving at121E C for15min.Final pH should be5.6±0.2at 25E C.Cool in slanted e for mold culture maintenance and inoculum preparation.(f)0.85%Saline.—Dissolve8.50g NaCl in water and dilute to 1L.Dispense into flasks or bottles and sterilize by autoclaving at 121E C for15min.(g)0.85%Saline with0.05%polysorbate80.—Dissolve8.5g NaCl in water,mix in0.50g polysorbate80,and dilute to1L.Dis-pense into suitable containers and sterilize by autoclaving at121E C for15min.(h)Barium sulfate standard No.2.—(1)Prepare a1.0% BaCl2solution by dissolving1.0g BaCl2⋅2H2O in100mL water.(2)Prepare a1.0%H2SO4solution by mixing1.0mL H2SO4in 100mL water.(3)Mix0.2mL solution,(1),with9.8mL solu-tion,(2),in a screw-capped test tube.Cap tightly and store in dark at room temperature.(i)Barium sulfate standard No.7.—Use solutions from C(h).Mix0.7mL solution,(h)(1),with9.3mL solution,(h)(2),in a screw-capped test tube.Cap tightly and store in dark at room temperature.D.Microorganisms(a)Staphylococcus aureus.—ATCC6538.(b)Staphylococcus epidermidis.—ATCC12228.(c)Klebsiella pneumoniae.—ATCC10031.(d)Escherichia coli.—ATCC8739.(e)Enterobacter gergoviae.—ATCC33028.(f)Pseudomonas aeruginosa.—ATCC9027.(g)Burkholderia cepacia.—ATCC25416.(h)Acinetobacter baumannii.—ATCC19606.(i)Candida albicans.—ATCC10231.(j)Aspergillus niger.—ATCC16404.(Note:Environmental microorganism(s)likely to be contami-nants of concern during product manufacture or use are included as a separate inoculum.Predominant environmental microbes isolated during manufacturing,equipment cleaning,and sanitizing,or from related deionized water systems are used as supplemental test inocula.)For culture revival and maintenance,consult references1and2.E.Product Quality Check(a)Weigh1.0g product into a screw-capped culture tube con-taining9.0mL sterile neutralizing broth to make a1:10dilution.If necessary to disperse product,add10to twenty3mm diameter glass beads to tube.Mix on Vortex mixer until homogeneous.(b)Pipet1.0mL of the1:10dilution into each of4sterile Petri plates.Pour15–20mL sterile molten Letheen agar(45±2E C)into each plate.Mix by rotating plates to disperse the dilution thoroughly. Let solidify.(c)Invert and incubate2plates at35±2E C for48h and2plates at 25±2E C for5days.(d)Count the number of colonies on all plates,add,and multiply by2.5to determine the number of colony forming units per gram (cfu/g)in the product.(e)Save plates to be used for the neutralization validation in M by refrigerating.F.Product Preparation(a)Measure20mL sterile saline into4sterile jars,B(a).Cap tightly and store at room temperature.(b)Weigh20g product into each of4sterile jars,B(a).Cap tightly and store at room temperature.G.Bacterial Inocula Preparation(a)Streak each bacterial culture,D(a)–(h),onto a nutrient agar, C(c),slant.Incubate48h at35±2E C.Wash each slant with5.0mL sterile saline,loosening the culture from the agar surface.Transfer the suspension into a sterile tube.Repeat the wash with second 5.0mL aliquot of bine washes and mix on Vortex mixer to disperse evenly.(b)Adjust each wash with sterile saline to yield a suspension of ca108cfu/mL using a McFarland BaSO4standard No.2,C(h),direct microscopic count,turbidimetry,absorbance,or other method cor-related to an aerobic plate count(APC),L.Perform an APC,L,on each suspension to confirm standardization.H.Fungal Inoculum Preparation(a)Streak C.albicans,D(i),on3slants of Y/M agar,C(d).Incu-bate at25±2E C for48h.Wash each slant sequentially with5.0mL aliquot of sterile saline.Repeat with a second5.0mL aliquot of ster-ile bine washes to produce10mL suspension.Mix on Vortex mixer to disperse evenly.(b)Adjust the wash with sterile saline to yield a suspension of ca 107cfu/mL using a McFarland BaSO4standard No.7,C(i),direct microscopic count,turbidimetry,absorbance,or other method that has been correlated to an APC,L.Perform an APC,L,on the suspen-sion to confirm standardization.(c)Streak A.Niger,D(j),on5slants of potato dextrose agar, C(e).Incubate at25±2E C for10days.Dislodge mold spores by add-ing5.0mL sterile saline containing0.05%polysorbate80to each tube and vigorously rubbing the surface of the agar slant with a ster-ile swab.Repeat with a second5.0mL aliquot in each bine the10washes to produce50mL suspension.Filter into a sterile con-tainer through3–5layers of sterile gauze supported in a funnel.Per-form an APC,L,using appropriate dilutions.Adjust mold suspen-sion to ca107per mL using sterile e immediately or refrigerate at2–5E C for up to1month.Verify mold viability by an APC,L,before each use.I.Inoculum Pools(a)Pool equal parts of the S.aureus and S.epidermidis suspen-sions,G(b),in a sterile container to make Inoculum Pool1: Gram-positive cocci.(b)Pool equal parts of the K.pneumoniae,E.coli,and E. gergoviae suspensions,G(b),in a sterile container to make Inoculum Pool2:Gram-negative fermentors.(c)Pool equal parts of the P.aeruginosa,B.cepacia,and A. baumanii suspensions,G(b),in a sterile container to make Inoculum Pool3:Gram-negative nonfermentors.(d)Pool equal parts of C.albicans,H(b),and A.niger,H(c),sus-pensions in a sterile container to make Inoculum Pool4:Fungi. (e)Use organism pools immediately or refrigerate them at2–5E C for no more than72h.J.Inoculation(a)Inoculate each of the four20.0mL aliquots of sterile saline,F(a), with0.2mL of its respective Inoculum Pool,I(a)–(d).Mix thoroughly. Use these suspensions to determine inoculum counts[see K(a)]. (b)Inoculate each of the four20g product suspensions,F(b), with0.2mL of its respective Inoculum Pool,I(a)–(d).Mix thor-oughly by shaking,Vortex mixing,or stirring,so that each suspen-sion contains106bacteria or105fungi per gram,evenly distributed throughout the product.Tightly close inoculated containers and store at ambient temperature(20–25E C).K.Sampling Intervals(a)Sample each inoculated saline suspension,J(a),for APC,L, within1h after inoculation to obtain inoculum count.(b)Test each inoculated product,J(b),for APC,L,at7,14,and 28days after inoculation to obtain product interval count.L.Aerobic Plate Count(APC)(a)Mix suspension thoroughly.Weigh1.0g product into a screw-capped culture tube containing9.0mL sterile neutralizing broth for a1:10dilution.If necessary to disperse product,add 10–20sterile3mm diameter glass beads to the tube.Mix on Vortex mixer until homogeneous.Table998.10Interlaboratory study results for determination of the efficacy of preservation of non-eye area water-miscible cosmetic and toiletry formulationsProduct name Incidence of false-negatives amongtotal positive samples aSensitivity rateIncidence of false-positives amongtotal negative samples bSpecificity rate Number Percentage Number PercentageShampoo2/494960/530100 Conditioner3/486940/540100 Water in oil emulsion0/5201001/50298 Oil in water emulsion0/5101000/510100 All combined5/2002981/2080.599.5a False-negative analysis indicates a sample is adequately preserved.b False-positive analysis indicates a sample is not adequately preserved.(b)Aseptically pipet0.1mL of the1:10dilution into a9.9mL tube of neutralizing broth to obtain a1:1000dilution.Vortex mix. Pipet0.1mL of the1:1000dilution into9.9mL neutralizing broth to obtain a1:100000dilution.The number of dilutions may be de-creased if previous counts of microbial populations show reduction.(c)Using a2.2mL pipet,aseptically pipet1.0and0.1mL aliquots from the1:10dilution into duplicate Petri dishes for the1:10 and1:100plates.If necessary,transfer duplicate1.0and0.1mL aliquots from the1:1000dilution for plates1:1000and1:10000,and from the1:100000dilution for plates1:100000and1:1000000. Pour15–20mL sterile Letheen agar,C(a),(45±2E C)into each plate.Mix by rotating the plates to disperse the suspension thor-oughly,and let solidify.(d)Invert bacterial plates and incubate at35±2°C.Examine bacterial plates after48–72h.Count plates in a suitable range (30–300colonies).If no countable plates fall in that range,count the plate(s)nearest that range showing distinct colonies.Average dupli-cate plate counts and express results as cfu/g of product.(e)Invert and incubate fungal plates at25±2°C.Read fungal plates at2–3days and record results.Count plates in a suitable range (30–300colonies).If no countable plates fall in that range,count the plate(s)nearest that range showing distinct colonies.Reincubate plates for another2–3days.Read and record additional colonies. Add to previous results to obtain total counts.Average duplicate plate counts and record as cfu/g of product.For information on aver-aging,refer to reference3.M.Neutralization CheckMake a1:10000dilution in sterile saline of Pools1,2,and3, I(a)–(c),and a1:1000dilution of Pool4,I(d).Streak each dilution for isolation with a10µL loop on the plates saved from E(e).If plates are not usable due to either desiccation or surface growth,re-peat section E,and streak freshly prepared plates.Incubate as in L(d)–(e).N.Data Analysis(a)Product quality check,E(d),must be found to contain <100cfu/g to proceed with the challenge test.(b)Inoculum counts,K(a),should be between1to9.9×106cfu/g product for bacteria and1to9.9×105cfu/g product for fungi,or the test should be repeated with different dilutions.(c)Neutralization check,M,must show significant growth of all pools to confirm adequate neutralization.A neutralizing broth other than D/E broth can be used.If neutralization does not occur,the test is invalid.Refer to references4–6for assistance.(d)Calculate the percent reduction:Reduction,%=inoculum count–product interval countinoculum count100(e)The test product is considered adequately preserved if(1)bac-teria show at least99.9%(3log)reduction within1week following challenge and remain at or below that level thereafter,and(2)fungi show at least a90%(1log)reduction within1week following chal-lenge,a99%(2log)reduction within2weeks following challenge, and remain at or below that level thereafter.These criteria apply to freshly prepared formulations.References:J.AOAC Int.84,101(2001).(1)Methods for General and Molecular Bacteriology(1993)P.Gerhardt(Ed.),American Society for Mi-crobiology,1752N St NW,Washington,DC20036-2804,USA.(2)Gherna,R.,Pienta,P.,&Cote,R.(1996)Catalogue of Bacteria and Phages,19th Ed.,ATCCBooks,PO Box753,Waldorf,MD20604-0753,USA.(3)U.S.Food and Drug Administration(1995)Bacteriological Analytical Manual,8th Ed.,AOACINTERNATIONAL,Gaithersburg,MD20877,USA.(4)“Standard Test Methods for EvaluatingInactivators of Antimicrobial Agents Used in Disin-fectant,Sanitizer,and Antiseptic Products(Designa-tion E1054-91)”(1998)in ASTM1998Annual Bookof Standards on Water and Environmental Technol-ogy,ASTM,100Barr Harbor Dr,WestConshohocken,PA19428-2959,USA.(5)Russell,A.D.(1999)in Principles and Practiceof Disinfection,Preservation,and Sterilization,3rdEd.,A.D.Russell,W.B.Hugo,&G.A.J.Ayliffe(Eds),Blackwell Scientific Publications,Oxford,UK,pp89–113.ISBN0632041943(6)Singer,S.(1987)Cosmetics&Toiletries,102,55–59.。