Rheological Properties and Shelf Life of Soft Cheese Made from Camel Milk Using Camel Chymosin

Abstract

This study was aimed to investigate the shelf life and rheological properties of soft cheese made from camel milk using streptococcus thermophilus (ST1-12) starter culture and camel chymosin as coagulant; and stored at a temperature of 4±1°C and 18±1°C for 1, 8, 15 and 22 days. The results revealed that the protein, fat and total solids content of the cheese significantly (P<0.05) increased during storage. Storage temperature significantly (P<0.05) affect the pH, titratable acidity, protein and fat content of cheese. Cheese sample kept at 18±1℃ was significantly (P<0.05) higher in total bacterial count (6.79 log cfu/g), coliform count (7.21 log cfu/g), yeast and mould counts (6.41 log cfu/g) than cheese sample kept at 4±1℃ which is 4.76 log cfu/g, 4.09 log cfu/g and 4.84 log cfu/g of total bacterial count, coliform count and yeast and mould counts, respectively. Firmness of the cheeses were significantly (P<0.05) affected by storage temperature and storage time. The firmness of the cheese sample stored at 4±1°C significantly (P< 0.05) increased from 3.77±0.17N on day one to 6.67±0.12N on day 22. Cheese stored at 4±1°C had acceptable shelf life till days 22 of storage period, but cheese that kept at 18±1℃ had a maximum shelf stability of 6 days without losing consumer acceptability. Therefore, soft cheese made from camel milk can be stored up to 22 days at lower temperature (4±1℃) and for 6 days at 18±1℃. Therefore, a resource poor society produces without cooling can store the soft cheese made from camel milk at 18±1℃ for about 6 days.