Buttermilk . The specific gravity of buttermilk ranges from 1,032 do 1,033. The fat content should not exceed the fat content if it is churned properly 0,5%. It consists of the tiniest little balls, which are the hardest to think.
As a material for cheese, buttermilk is of no value except when used as an additive to milk intended for curd cheese.
The chemical composition of harvested milk and buttermilk (according to Fleischmann)
| water | Centrifuged milk % | Stand milk % | Buttermilk % |
| 90,40 | 89,85 | 91,30 | |
| fat | 0,05 | 0,75 | 0,40 |
| proteins | 4,00 | 4,03 | 3,50 |
| milk sugar | 4,70 | 4,60 | 4,00 |
| mineral salts | 0,75 | 0,77 | 0,70 |
Siara. The milk that is released during the birth period is called colostrum or juvenile milk. It is yellow or brown in color, pungent smell, taste a bit salty, acidic reaction (up to 0.3%). Water content from 73 do 76%, dry matter from 24 do 27%, including fat from 3,3 do 4%, cheesecake 4%, albumin 8%, globulins 8%, milk sugar o 1,8 do 2,5%, mineral salts from 1,0 do 1,2%; the specific gravity is 1,066, pH of 6,2 do 6,4. Compared to milk, it contains many albumin, globulin and mineral salts, while little milk sugar. Due to the large amount of albumin, colostrum is formed, that is, it cuts it down while cooking. When added, even in small amounts, to milk, it weakens its coagulation ability under the influence of rennet, hinders the drying of the cheese mass and can cause defects in the cheese, because albumin and globulin act in excess as foreign bodies here, behaving differently from casein. Therefore, colostrum should not be delivered to the cheese dairy, before its specific gravity falls to 1,034, and acidity below 0,18%, which usually occurs after 7 do 10 days, counting from calving. Antenatal milk also has all the characteristics of colostrum. For the reasons mentioned, and also for the health of the pregnant animal and the development of the fetus, milking should be stopped at least for 6 weeks before calving. The colostrum belongs to the calf.