ExFLP-5 Determination of Extraneous Material in Cheese
|
ID： |
8AA9E48703D54B05AA75060055E2CE9F |
|
文件大小(MB)： |
0.02 |
|
页数： |
3 |
|
文件格式： |
|
|
日期： |
2012-3-3 |
|
购买： |
文本摘录（文本识别可能有误，但文件阅览显示及打印正常，pdf文件可进行文字搜索定位）：
Government of Canada Gouvernement du Canada,Laboratory Procedure ExFLP-5,April 1995,HEALTH PROTECTION BRANCH,OTTAWA,DETERMINATION OF EXTRANEOUS MATERIAL IN CHEESE,M.-A. Rivers,Research Division, Bureau of Microbial Hazards,Food Directorate, Postal Locator: 2204A2,Health Canada, Ottawa ON K1A 0L2,1. APPLICATION,This method is applicable to the sampling and examination of cheese for all extraneous material (light and heavy filth),to determine compliance with Sections 4, 5 and 7 of the Food and Drugs Act. This method replaces ExFLB No 10 by,McClymont Peace, Gardiner and van Walbeek.,2. DEFINITION OF TERMS,A lot is defined as that amount (volume, weight, etc.) of the food which is produced, stored and/or shipped under,conditions as nearly uniform as possible, preferably designated by a common container code or marking, and, in any,event, consisting of not more than one variety, grade or type of product from a single identifiable source.,3. COLLECTION OF SAMPLES,3.1 Scrutinize the entire lot for live infestation. If live infestation is found, do not sample until after fumigation or,other effective treatment.,3.2 Obtain three sample units of at least 225 g each, selected at random from the lot using appropriate sampling,equipment and containers. Three sample units constitute a sample.,3.3 Each sample unit must be kept separate and labelled 1, 2 and 3. Complete information respecting the lot size,weight of individual containers, country of origin, exporter, importer, or domestic manufacturer, and product and,lot identification should be recorded and should accompany the sample.,4. MATERIALS AND SPECIAL EQUIPMENT,1) Balance,2) Sharp knife,3) 2 L beaker,4) Mechanical stirrer,5) Hot plate,6) pH meter or pH paper (range pH 5-9),7) Wash bottles,8) Incubator or oven maintained at #40EC,ExFLP-5,- 2 - April 1995,9) U.S. standard No. 230 sieve,10) Suction filtration apparatus with Buchner or Hirsch funnel (5-7 cm perforated plate),11) Ruled filter paper. Filter paper should be larger than funnel plate (7-9 cm),12) Petri dishes to suit size of filter paper used,13) Stereoscopic microscope (10-30x),14) EDTA tetrasodium salt solution. Dissolve 20 g of Na4EDTA in water and make up to 100 mL.,15) Concentrated NH4OH,16) Concentrated HCl,17) Dilute HCl (1:2 in water),18) Antifoam B solution (BDH Chemicals),19) Pancreatin solution. Use United States Pharmacopeia or soluble pancreatin kept refrigerated (4EC). Use a,fresh solution of 5 g per 100 mL of water at #40EC. Stir with a blender for 10 min or let stand 30 min with,frequent shaking. Centrifuge 10 min at 1500 rpm and filter supernate through S&S No. 8 paper or equivalent.,Alternatively, filter through cotton pads 10-13 cm thick and then through rapid No. 8 paper in a Hirsch funnel,with suction.,20) Detergent solution (1% sodium lauryl sulphate),21) No. 60 screen (metal or plastic - 5 to 7 cm diameter),22) Alcohol, either 95% ethanol or 99% isopropanol,23) Glycerol-95% ethanol mixture (1:1),5. PROCEDURE,The examination shall be carried out in accordance with the following instructions.,5.1 Analytical Units.,5.1.1 Prepare cheese for sampling by trimming and discarding thin layers to remove all old cut surfaces and to keep,paraffin coating and mould out of sample.,5.1.2 In a random fashion from a sample unit, weigh 225 g. This 225 g constitutes an analytical unit.,5.1.3 Repeat step 5.1.2 for remaining two sample units.,5.2 Isolation,5.2.1 Transfer and break up the analytical unit into a 2 L beaker. Add 700 mL of filtered water at approximately 55EC.,5.2.2 Set beaker under the mechanical stirrer and on a hot plate. Stir 15 min and maintain the mixture at 55EC.,5.2.3 Add 100 mL of 20% aqueous Na4EDTA solution, stir and adjust the mixture to pH 8 with NH4OH or dilute HCI,(1:2) as required. Rinse sides of beaker free of adhering cheese particles with water at approximately 60EC.,5.2.4 Maintain at pH 8 by adding NH4OH or dilute HCl (1:2) as required. If foaming occurs add several drops of,Antifoam B compound. Continue stirring until cheese becomes finely dispersed.,5.2.5 Cool slurry to 40EC and maintain at pH 8. Add 100 mL of 5% pancreatin solution.,ExFLP-5,- 3 - April 1995,5.2.6 Let mixture digest at >35EC #40EC with continued stirring for 1.5-3 h. Maintain at pH 8 by the addition of,NH4OH.,5.2.7 Wet sieve cheese using a No. 230 sieve with hot (50-70oC) tap water until rinse water is clear. Place sieve in,a shallow pan, cover residue to a depth of approximately 2 cm with hot (65-70oC) detergent (1% sodium lauryl,sulphate), leave for 5 min, drain and wet sieve with hot tap water until all suds have washed through. Be careful,not to allow suds to foam ……
……