BS ISO 9622:2013 pdf free

BS ISO 9622:2013 pdf free.Milk and liquid milk products – Guidelines for the application of mid-infrared spectrometry
NOTE 1 The linearity check described in this subclause applies only to the measurement of major components in milk. Linearity checks for other applications, particularly for higher fat products or for parameters other than the major constituents, will differ. It is intended that the manufacturer’s guidelines be followed in these cases.
NOTE 2 Linearity can be assessed on either a mass/mass basis or a mass/volume basis. Since the instrument cuvette holds a specific volume of sample, it is most ideal to assess linearity on a mass/volume basis. In either case, linearity solutions are prepared by accurately weighing fractions. To assess linearity on a volume basis, it is intended that accurate density measurements be conducted and appropriate conversions be calculated.
NOTE 3 It is critical, prior to assessing linearity, to confirm that the instrument homogenizer is functioning appropriately (see 6.1.3).
Tocheck the linearity for each ofthe major components, make up atleast 10 solutionsofknownconcentration,which cover the typical range for the specific component. The following solutions are recommended.
a) Homogenized cream with a mass fraction of fat of 8 %, diluted with skimmed milk or zero solution to check the linearity for the determination of the fat content. If homogenized cream at this fat level is unavailable, unhomogenized cream may also be used providing the instrument homogenizer is functioning at an acceptable level (see 6.1.3).
b) UF skimmed milk retentate diluted with ultrafiltrate to check the linearity for the determination of the protein content. Alternatively, whey protein concentrate, sodium caseinate, calcium propionate,skim milk powder or evaporated skim milk diluted with distilled water may also be used. The stock solution should contain a mass fraction of approximately 5,5 % of protein.
c) A solution of 60 g/l of lactose monohydrate, diluted with water or a milk mineral solution[14] to check the linearity for the determination of the lactose content.
Using a stock solution, which has a concentration at the upper end of the typical range, serial dilutions can be made as follows in Table 1.BS ISO 9622 pdf download.