23 



ILLUSTRATION. 



Grams. 



Weight of dish 101. 55 



Weight of milk and dish 111. 25 



Weight of milk used 10. 30 



Weight of dish and dried milk (solids) 102. 85 



Weight of dish and solids less weight of dish 102. 85—101. 55=1. 30 



Hence, 10. 3 grams of milk contain 1. 3 grams of solids. 

 1. 3-5-10. 3=12. 62 per cent of .solids in milk. 



2. Determination of whey solids. — Follow instructions given under 

 preceding experiment, using, if possible, whey produced by same lot of 

 milk used above. 



ILLUSTRATION. 



Grams. 



Weight of dish 101. 55 



Weight of whey and dish 111. 83 



Weight of whey used 10. 28 



Weight of dish and dried whey (solids) 102. 20 



Weight of dish and solids less weight of dish 102. 20—101. 55=0. 65 



0. 65-f-lO. 28=6. 32 per cent of solids in whey. 



3. To determine per cent of cheese solids in milk. — Subtract per cent 

 of whey solids from per cent of milk solids. 



ILLUSTRATION. 



Per cent. 



Milk solids 12. 62 



Whey solids 6. 32 



Cheese solids 6. 30 



THIBD USCTTJRE. 

 CARE OF MILK TO BE USED IN CHEESE MAKING. 



1. Necessity of clean milk. — One of the fundamental conditions of 

 successful cheese making is clean milk. Milk may appear to be in good 

 condition when being made into cheese, but may contain organisms 

 that develop later in and spoil the cheese. 



2. Sources of contamination. — Assuming that milk is in every way 

 normal as it leaves the udder of the cow, it may later become unfit for 

 cheese making by the presence of bad odors and tastes, resulting from 

 (1) food eaten, (2) flavors absorbed, and (3) bacterial infection. Other 

 conditions apart from bad flavors, such as souring, make milk unfit 

 for Cheddar cheese making. 



3. Flavors from foods eaten. — Certain foods that have strong taste 

 and odor impart to milk their characteristic flavors. Most common 

 among these are onions, garlic, turnips, cabbages, ragweed, etc. (ref- 

 erences No. 3, p. 25; No. 8, p. 13, and No. 9, p. 61). 



4. Absorption of flavors by milk. — Milk, particularly if warm, absorbs 

 odors present in the surrounding air. The most common sources of 

 such odors are the manure in unclean stables and any strongly fla- 



