Cheese Curd:solid casein from lactic acid bacteria and rennin 。 Whey:liquid separated from curd 。Hard cheeses produced by lactic acid bacteria (a)The milk has been coagulated by the action of rennin Semisoft cheeses (forming curd)and is inoculated with ripening bacteria for flavor and acidity.Here the workers are cutting the ripened by Penicillium curd into slabs. on surface Figure 28.8a Cheese Figure 28.8a • Curd: solid casein from lactic acid bacteria and rennin • Whey: liquid separated from curd • Hard cheeses produced by lactic acid bacteria • Semisoft cheeses ripened by Penicillium on surface