Investigation on the Effect of Persian Gum and Transglutaminase Enzyme on Some Physicochemical and Microstructural Characteristics of Low-Fat Ultrafiltrated Iranian White Cheese

Abstract

This study aimed to assess the effect of Persian gum (PG) and microbial transglutaminase enzyme (MTGase) on some physicochemical and microstructural characteristics of low-fat ultrafiltrated Iranian white cheese during 60 days of cold storage. To manufacture the low-fat cheese samples, PG (0%, 0.25%, and 0.5%) and MTGase (0, 0.5 and 1 U/g of protein) were used and cheeses (low- and full-fat) without PG and MTGase were considered as controls. The obtained results revealed that the treated samples with PG had a higher titratable acidity, moisture content, and moisture-to-protein ratio (M:P), but a lower protein content as compared to the low-fat control (p ≤ 0.05). Furthermore, the cheese samples treated with the higher level of MTGase (i.e., 1 U/g of protein) had a higher protein and fat content (p ≤ 0.05). Methyl palmitate (C_16:0) and methyl oleate (C_18:1) were found to be the most abundant fatty acids in the tested cheeses. Additionally, scanning electron micrographs revealed that addition of PG and MTGase improved the microstructure of the samples, so that the sample containing 0.5 U enzyme and 0.5% gum was more similar to its full-fat counterpart and obtained the highest overall acceptance score among the cheeses. Therefore, our findings revealed that with incorporation of PG and MTGase, a low-fat ultrafiltrated white cheese could be produced with an appropriate functional, physicochemical, and microstructural characteristics comparable to the full-fat product.