Effect of using Acacia nubica Extract as coagulant on physiochemical and sensory characterization of white soft cheese during storageperiod

Abstract

The aim of this study is to determine the effect of Acacia nubica bark extract as coagulant on the RCT yield and chemical composition of white soft cheese during storage period. In this study two experiments were carried out, the first experiment for enzyme extraction from the Acacia nubica bark and the second experiment two treatments were done, in the first treatment white cheese was processed with rennet enzyme as control in the second treatment Acacia nubica bark extract was used as coagulant for white cheese making. Ten liters of fresh cows’ milk were purchased from the diary farm of the College of Animal Production Science and Technology at Sudan University of Science and Technology. Milk for cheese making was pasteurized at 72Co for 15 sec, then cooled to 45CO. Calcium chloride was added at the rate of 0.02% and 2 % of starter culture were added, and then rennet enzyme and the Acacia nubica extract were added at the rate of 0.08gm and 25 ml, respectively .until coagulation occurred then the whey was drained and the curd was placed into mold lined with fine cloth for overnight pressing then the curd was cut into cubes of 200 g with salted whey into plastic bags then stored at room temperature 37Co for 21 days. The chemical composition and sensory evaluations were done for the cheese samples at 0, 7, 14 and 21days intervals. The results showed that the Acacia nubica extract was significantly highly active as coagulant and as proteolytic, also the results revealed that no significant variation in the coagulation time was found between Acacia nubica extract and rennet enzyme, the yield was significantly higher in the cheese samples with rennet enzyme. The chemical composition was not significantly affected by coagulant type. However, the storage period was significantly affected on the chemical composition of the white cheese samples, the coagulant type was significantly affected the organoleptic quality of the white cheese samples, the cheese samples with rennet enzyme showed slightly better in the quality attributes.