Kirkuk University Journal For Agricultural Sciences

Abstract

Ras cheese was produced from Iraqi buffalo milk treated with trypsin enzyme and calcium chelating agent to modify casein micelle size and lower the calcium content. Ten treatments of buffalo milk were manufactured by adding different ratio of trypsin enzyme and different ratio of sodium polyphosphate and different ratio of mixed of enzyme and chelating agent, with control treatment from untreated buffalo milk. Ras cheese made from enzyme treatments (0.04 and 0.08 unit) were showed an increased the moisture and soluble nitrogen contents in ras cheese, and decreased in the total calcium and total nitrogen in the curd. This treatment also showed increased in coagulation time and whey draining, with decreased in in curd tension, miltability and firmness. Treating buffalo milk with calcium chelating agent (1.25 and 2.5 gm.) significantly increased the moisture, whey draining, coagulation time, and soluble nitrogen contents of ras cheese and decreased the total calcium, total nitrogen, curd tension and meltability There were no different in amino acids. Buffalo milk treated with trypsin enzyme and calcium chelating gent, (0.04unit +1.25 and 2.5 gm.) and (0.08 unit + 1.25 and 2.5 gm.) were higher in moisture, soluble nitrogen, whey draining and coagulation time and lower in total calcium, total nitrogen, meltability, curd tension Buffalo milk treating at 75°C30 min.increased moisture and soluble nitrogen of ras cheese and decreased in total calcium and total nitrogen.Results also noticeable improvements in functional properties by decreased meltability and curd tension and increased coagulation time and whey draining.