Effect of Type of Milk and Storage Period on the Quality of Hard Cheese

Abstract

The objective of this study was to determine the effect of storage period on the chemical composition of hard cheese (“Roomi”), manufactured from cow and goat milks and their blends (1:1). A starter culture 1% of Streptococcus thermophills and Lactobacillus bulugaricus and rennet tablet (one tablet /50 litre milk) were used. The curd was cheddared, salted, moulded, pressed overnight, coated with paraffin wax and stored at 12±2oC for ripening. The proximate analysis of cheeses reflected changes in total solids, total protein and fat contents towards ripening. Cheese prepared from goat milk recorded higher level of solids and fat than cow and blend cheeses. Cow cheese showed significantly (P≤0.05) higher level of protein than goat and blend cheeses. The pH of the three types of cheeses significantly (P≤0.05) decreased in concomitance with increase in their titratable acidity of all cheeses. The soluble nitrogen content increased significantly (P≤0.05) during ripening of all cheeses. The ratio of soluble nitrogen to total nitrogen also increased significantly (P≤0.05) during ripening of all cheeses.