The effects of camel chymosin and Withania coagulans extract on camel and bovine milk cheeses

Abstract

Withania coagulans (W. coagulans) extract and camel chymosin have aspartic protease capable of coagulating milk for cheese production. This study investigated the quality of camel and bovine milk cheeses coagulated using Withania extracts, came chymosin, and their mixture in two experiments. In Experiment (1), a factorial design with four factors (W. coagulans, camel chymosin, incubation time, and incubation temperature) was performed. The effect of these factors on cheese’s yield and hardness were assessed. An enzyme concentration corresponding to a 36 µg/L of milk of W. coagulans, 50 IMCU/L of camel chymosin, holding time of 4 h, and incubation temperature of 60 °C provided the optimal textural hardness for both camel and bovine milk cheeses. Seven treatments were analyzed in experiment (2) were analyzed for physicochemical properties, yield, and sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGEitation). The results showed that pure Withania extract exhibited the lower coagulating effect resulting in cheeses with low yield, hardness, fat, protein, and total solids. The SDS-PAGE electropherograms of camel cheese showed several low molecular weight bands as compared to bovine cheese. This phenomenon is due to excessive proteolysis in camel cheese, which we believed is caused by the presence of endogenous enzymes.

The Texture of Camel Milk Cheese: Effects of Milk Composition, Coagulants, and Processing Conditions

“…κ-casein is considered the primary factor responsible for coagulation of milk ( 17 , 58 , 80 – 82 ). However, the high level of β-casein in CM seems to also play an important role in this effect ( 11 , 61 , 76 ) in agreement to what has been described for BM ( 82 ). β-Casein possesses higher hydrophobicity than the other milk proteins and has more chaperone-like activities leading to suppression of protein aggregation ( 83 ).…”

“…SDS-PAGE electrophoresis shows clear differences in the protein and peptide profiles of CM and BM cheeses and whey ( Figure 2 ). The CM cheeses show several low molecular weight bands suggesting that excessive proteolysis of caseins has occurred in these cheeses ( 61 , 76 ). Endogenous enzymes such as plasmin in CM ( 94 – 96 ) might be responsible for the hydrolysis of caseins, especially β-casein.…”

“… Correlations between camel and bovine cheese hardness and yield showing similar trends but different magnitudes. Source: Mbye et al ( 76 ). …”

“…Plant proteases have been divided into groups based on the hydrolytic process mechanism: aspartate, serine, and cysteine proteases. Serine protease such as Zingiber officinale extracts ( 147 ), cysteine proteases isolated from Ficus carica ( 73 ), and aspartic proteases from Withania coagulans ( 76 ) have been used in CM cheese production and the resultant cheeses were found acceptable. The effects of camel chymosin and Withania coagulans extracts on the coagulation of CM and BM cheeses' yield and textural quality have been compared and again, CM was found to have a longer gelation time and softer cheese compared to BM ( 76 ).…”

“…Serine protease such as Zingiber officinale extracts ( 147 ), cysteine proteases isolated from Ficus carica ( 73 ), and aspartic proteases from Withania coagulans ( 76 ) have been used in CM cheese production and the resultant cheeses were found acceptable. The effects of camel chymosin and Withania coagulans extracts on the coagulation of CM and BM cheeses' yield and textural quality have been compared and again, CM was found to have a longer gelation time and softer cheese compared to BM ( 76 ). This study showed that the yield of un-ripened CM cheese produced by chymosin or the Withania extracts was consistently higher than that of BM cheeses due to higher moisture entrapment, which led to reduced cheese hardness ( Figure 3 ).…”