242 CREAM RIPENING 



use for cream ripening equipment, These vats, from the stand- 

 point of their protection of the cream and butter against the 

 oxidizing influence of exposed metals such as iron and copper, 

 and the damaging effect of such chemical action to the quality 

 of the butter, are as nearly ideal as can be desired and this de- 

 sirability, and the absence of the necessity of frequent recoating 

 are additional factors in their favor. 



In the presence of these facts it appears reasonable to be- 

 lieve that as soon as the commercial butter manufacturers fully 

 realize this disastrous influence of copper and copper .salts on 

 cream and butter, and learn to appreciate the feasibility of 

 using glass-enameled vats in the creamery, glass-enameled vats 

 will commence to take the place of copper-lined vats in a similar 

 way as has been the case for years in the brewery and the con- 

 densed milk factory, and is now the case in oleomargarine fac- 

 tories, market milk and ice cream plants. This change will result 

 in a marked improvement of the quality of butter, and especially 

 of butter for storage purposes. 



Amount of Starter to Add to Cream. The amount of 

 starter to add to the cream depends on such factors as the tem- 

 perature at which the cream is to be ripened, season of the 

 year, the length of time during which the cream is to be 

 ripened, the richness of the cream and the availability of the 

 starter. The amount of starter that is used under normal con- 

 ditions ranges from 5 per cent to 20 per cent, though larger 

 amounts may be used to good advantage under certain con- 

 ditions. 



At low ripening temperatures more starter is needed to 

 ripen the cream than at high temperatures. When ripening 

 around 50 F., 20 per cent starter is desirable, while at 65 F. 

 10 to 15 per cent starter should be quite sufficient. 



If the time during which cream must be ripened is short, 

 a relatively larger amount of starter is needed. Where condi- 

 tions necessitate the prolonging of the ripening process, a less 

 amount of starter should be used in order to guard against 

 the danger of over-ripening. 



More starter is usually needed to ripen the cream in winter 

 than in summer, because both, atmospheric conditions and the 



