CREAMERY BUTTER MAKING 263 



acid bacteria by daily transferring them to a new 



medium such as sweet pasteurized skim-milk. 

 Proteids. — Nitrogenous substances like casein and albu- 

 men. 

 Reducing Valve. — A valve used for regulating steam 



pressure. 

 Refrigerant. — In mechanical refrigeration a substance 



whose evaporation produces cold. 

 Rennet. — The curdling and digesting principle of calf 



stomach. 

 Scoring. — A term used synonymously with judging. 

 Secretion. — The act of separating or producing from the 



blood by the vital economy. 

 Septic. — Promoting decay. 

 Specific Gravity. — The weight of one body as compared 



with an equal volume of some other body taken as 



a standard. 

 Specific Heat. — The quantity of heat required to raise 



the temperature of a body one degree. 

 Solution. — The state of being dissolved. 

 Spore. — The resting or non-vegetative stage of certain 



kinds of bacteria. 

 Steam Trap. — An arrangement by which condensed 



steam may be taken out of heating pipes without the 



escape of steam. 

 Sterilization. — The process of destroying all germ life 



by the application of heat near 212° F. 

 Strippers' Milk. — The milk from cows far advanced in 



the period of lactation. 

 Strippings. — The last few streams of milk drawn from 



each teat. 

 Suspension. — The state of being held mechanically in a 



liquid, like butter fat in milk. 



