GENERAL PROVISIONSU.K.
1.PREPARATION OF THE SAMPLE FOR CHEMICAL ANALYSISU.K.
1.1.Unsweetened condensed high fat milkU.K.
Unsweetened condensed milk
Unsweetened condensed partly skimmed milk
Unsweetened condensed skimmed milk
Shake and invert the closed can. Open the can and slowly pour the milk into a second container which can be closed hermetically, mixing by repeated transfer. Ensure that all remaining fat and milk adhering to the wall and the ends of the can are mixed in with the sample. Close the container. If the contents are not homogeneous warm the container in a waterbath at 40 oC. Shake vigorously every 15 minutes. After two hours, remove the container from the water-bath and let it cool to room temperature. Remove the lid and thoroughly mix the contents of the container with a spoon or spatula (if the fat has separated the sample should not be tested). Store in a cool place.
1.2.Sweetened condensed milkU.K.
Sweetened condensed partly skimmed milk
Sweetened condensed skimmed milk
Cans: Warm the closed can in a waterbath at 30 to 40 oC for about 30 minutes. Open the can and thoroughly mix the contents with a spatula or a spoon by making upward, downward, and circular movements in order to obtain an intimate mixture of the top and bottom layers with all the contents. Ensure that the remaining milk adhering to the wall and end of the can is incorporated in the sample. As far as possible, pour the contents into a second container provided with an air-tight lid. Close the container and store in a cool place.
Tubes: Cut the end and pour the contents into a container provided with an air-tight lid. Next, cut the tube lengthwise. Scrape out all material adhering to the interior and mix it carefully with the rest of the contents. Store the container in a cool place.
1.3.Dried high fat milk or high fat milk powderU.K.
Dried whole milk or whole milk powder
Dried partly skimmed milk or partly skimmed-milk powder
Dried skimmed milk or skimmed-milk powder
Transfer the milk powder to a clean, dry container (with air-tight lid) of a capacity of twice the volume of the powder. Close the container immediately and thoroughly mix the milk powder by repeatedly shaking and inverting the container. During the preparation of the sample exposure of the milk powder to the atmosphere should be avoided as far as possible to minimize absorption of moisture.
2.REAGENTSU.K.
2.1.WaterU.K.
2.1.1.Wherever mention is made of water for dissolution, dilution or washing purposes, distilled water, or demineralized water of at least equivalent purity shall be used.U.K.
2.1.2.Wherever reference is made to ‘dissolution’, ‘solution’ or ‘dilution’ without further indication, ‘dissolution in water’, ‘solution in water’ and ‘dilution in water’ is meant.U.K.
2.2.ChemicalsU.K.
All chemicals used shall be of recognized analytical reagent quality except where otherwise specified.
3.EQUIPMENTU.K.
3.1.Lists of equipmentU.K.
The lists of equipment contain only those items with a specialized use and items with a particular specification.
3.2.Analytical balanceU.K.
Analytical balance means a balance capable of weighing to at least 0,1 mg.
4.EXPRESSION OF RESULTSU.K.
4.1.Calculation of percentageU.K.
Except where otherwise specified, the results shall be calculated as a percentage by mass of the sample as received by the laboratory.
4.2.Number of significant figuresU.K.
The result shall not contain more significant figures than are justified by the precision of the method of analysis used.
5.TEST REPORTU.K.
The test report shall identify the method of analysis used as well as the results obtained. In addition, it shall mention all details of procedure not specified in the method of analysis, or which are optional, as well as any circumstances that may have influenced the results obtained.
The test report shall give all the information necessary for the complete identification of the sample.