ISO 19662:2018 pdf free

ISO 19662:2018 pdf free.Milk一Determination of fat content- Acido-butyrometric
Remove the butyrometer from the centrifuge, adjusting the stopper if necessary, to bring the fat column onto the scale. Place the butyrometer, stopper downwards, in a water bath (6.2) at 65 °C±2 °C for 10 min; the water level shall be above the top of the fat column.
Remove the butyrometer from the water bath, stopper still downwards, and carefully adjust the stopper by pulling on it in order to bring the bottom of the fat column, with minimum column movement, in line with the nearest mark, preferably a main graduation line. (It is recommended to choose the 0 graduation line of the butyrometer as mark A.)
Note the graduation line (A) corresponding to the bottom of the fat column, then, taking care not to move the latter, note, as quickly as possible, the graduation line (B) coincident with the lowest point of the meniscus at the top of the fat column.
Carry out the reading to within 0,025 g per 100 ml or 100 g.
While reading, the butyrometer shall be held and moved vertically, in order to obtain the reading point at eye level and avoid parallax error. (Do not move the head.)
No more than 10 s shall elapse between the removal of the butyrometer and the end of the reading.
If it is necessary to verify the obtained result, replace the butyrometer in the water bath for approximately 5 min, then remove it and take the readings as indicated in the previous paragraph.
The repeatability and reproducibility values are expressed with a probability level of 95 % and were obtained from interlaboratory tests according to ISO 5725-2[5]. Details on the interlaboratory collaborative tests are summarised in Annex C.
The difference between two single results, obtained on an identical product submitted to the same test by the same operator within a short interval of time, shall not exceed 0,05 g per 100 ml or 100 g.
The difference between two single independent results, obtained by two operators working in different laboratories on an identical product submitted to a same test, shall not exceed 0,1 g per 100 ml or 100 g.ISO 19662 pdf download.