Effect of camel chymosin on the texture, functionality, and sensory properties of low-moisture, part-skim Mozzarella cheese

Abstract

The objective of this study was to compare the effect of coagulant (bovine calf chymosin, BCC, or camel chymosin, CC), on the functional and sensory properties and performance shelf-life of low-moisture, part-skim (LMPS) Mozzarella. Both chymosins were used at 2 levels [0.05 and 0.037 international milk clotting units (IMCU)/mL], and clotting temperature was varied to achieve similar gelation times for each treatment (as this also affects cheese properties). Functionality was assessed at various cheese ages using dynamic low-amplitude oscillatory rheology and performance of baked cheese on pizza. Cheese composition was not significantly different between treatments. The level of total calcium or insoluble (INSOL) calcium did not differ significantly among the cheeses initially or during ripening. Proteolysis in cheese made with BCC was higher than in cheeses made with CC. At 84 d of ripening, maximum loss tangent values were not significantly different in the cheeses, suggesting that these cheeses had similar melt characteristics. After 14 d of cheese ripening, the crossover temperature (loss tangent = 1 or melting temperature) was higher when CC was used as coagulant. This was due to lower proteolysis in the CC cheeses compared with those made with BCC because the pH and INSOL calcium levels were similar in all cheeses. Cheeses made with CC maintained higher hardness values over 84 d of ripening compared with BCC and maintained higher sensory firmness values and adhesiveness of mass scores during ripening. When melted on pizzas, cheese made with CC had lower blister quantity and the cheeses were firmer and chewier. Because the 2 types of cheeses had similar moisture contents, pH values, and INSOL Ca levels, differences in proteolysis were responsible for the firmer and chewier texture of CC cheeses. When cheese performance on baked pizza was analyzed, properties such as blister quantity, strand thickness, hardness, and chewiness were maintained for a longer ripening time than cheeses made with BCC, indicating that use of CC could help to extend the performance shelf-life of LMPS Mozzarella.

Effect of rennet on the composition, proteolysis and microstructure of reduced-fat Cheddar cheese during ripening

“…Previous studies have similarly reported lower proteolysis when Cheddar cheese was made with FCC instead of FPC (Bansal et al 2009;Govindasamy-Lucey et al 2010) but these results were attributed to a lower strength of FCC rennet; the rennet strengths used in the first study were ∼0.039 IMCU.g −1 of milk) of FCC and ∼0.058 IMCU.g −1 of milk of calf chymosin and in the second study 0.039 IMCU.g −1 of milk of FCC and 0.0485 IMCU.g −1 of milk of calf chymosin respectively. Moynihan et al (2014), however, also observed lower levels of proteolysis when cheeses were made with FCC added at the same rennet concentration as FPC, consistent with this study. The findings of this study confirm that the proteolytic activity in cheese is reduced even when FCC is used at a similar rennet strength, consistent with reports of the lower proteolytic activity of the isolated enzyme.…”

“…For example, Sheehan et al (2004) showed that reduced-fat Mozzarella cheese made with R. pusillus proteinase resulted in higher levels of pH 4.6 soluble nitrogen during ripening, when compared to cheeses made with either FPC or R. miehei proteinase. The impact of FCC on the properties of Cheddar and Mozzarella has been reported previously (Govindasamy-Lucey et al 2010;Bansal et al 2009;Moynihan et al 2014;Børsting et al 2012). FCC has a much higher ratio of milk clotting activity/general proteolytic activity, known as a C/P ratio, compared to bovine chymosin.…”

“…The rennet concentration, however, did not significantly affect cheese hardness. Moynihan et al (2014) also showed that low-moisture partskim Mozzarella cheese made with high concentrations of bovine chymosin had higher proteolysis after 28 days, as indicated by pH 4.6 soluble nitrogen, than the cheese made with low concentrations of bovine chymosin. In the same study, however, it was also observed that the hardness of cheeses made with high and low bovine chymosin did not differ significantly during ripening.…”

“…The concentration of α s -CN and the hardness or springiness of the cheese, however, were not significantly affected. A study by Moynihan et al (2014) also found that low-moisture part-skim Mozzarella cheese had similar hardness when made with different rennet concentrations. These studies are in contrast with a study on Gouda cheese made with ultrafiltered milk that observed a significantly harder and less bitter cheese with a twofold reduction in rennet concentration (Spangler et al 1991).…”

Spatiotemporal Characterization of Texture of Crescenza Cheese, a Soft Fresh Italian Cheese

“…Crescenza C obtained with FPCC and direct-to-vat starter culture showed the significantly highest values of Ha and CW and the lowest values of Ads. FPCC can produce a firmer cheese structure as already reported [23][24][25] also for Crescenza cheese and is probably related to its lower general proteolytic activity than calf chymosin [26] and to the presence of pepsin in calf rennet. On the other hand, Crescenza cheeses that were both obtained with calf rennet but with a different acidifying starter (directto-vat versus bulk starter composed of different biotypes of S. thermophilus) showed smaller differences that could be Crescenza N was manufactured using a direct-to-vat starter culture of St. thermophilus and calf rennet.…”