UF-white soft cheese cross-linked by rosemary transglutaminase

Abstract

Background: Enzymatic cross-linking of UF-white soft cheese by transglutaminase enzyme extracted from rosemary (Rosmarinus officinalis L.) leaves (RTGase) was evaluated. Materials and Methods: The RTGase was used in UF-white soft cheese at the level of 2.5, 5.0 and 7.5 U g-1 protein to examine the chemical, organoleptic properties and protein quality evaluation of cheese during storage period (1, 7, 15, 21 and 30 days). Results: The control cheese had the lowest acidity percentage and the highest total nitrogen/dry matter and dry matter values compared with other cheese treatments. However, water soluble nitrogen percentage of RTGase cheese was significantly (p≤0.05) lower than that detected in control cheese. Fat/dry matter of UF-white soft cheese treated with RTGase was significantly (p≤0.05) lower than that of control cheese during all storage period. After 30 days of storage period, the essential amino acids content, total essential amino acids/total amino acids ratio, protein efficiency ratio and biological value of RTGase cheese were higher than those of control cheese. The body and texture, flavor and total score of cheese treated with RTGase were higher than those of control cheese during all storage period. Conclusion: The RTGase treated cheese at the level of 5.0 U g-1 protein had significantly (p≤0.05) differences compared to control cheese in body and texture after 7 days until 30 days of storage period reflects the TGase cross-linking reaction and improves cheese textural, sensorial and nutritional properties.