Fang Wang1, Wei Zhang1, Fazheng Ren2. 1. The Innovation Centre of Food Nutrition and Human Health, Beijing Laboratory for Food Quality and Safety, Beijing Key Laboratory of Agricultural Product Detection and Control of Spoilage Organisms and Pesticide Residue, College of Food Science and Engineering, Beijing University of Agriculture, Beijing, China. 2. The Innovation Centre of Food Nutrition and Human Health, College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China.
Abstract
BACKGROUND: Carrageenan (CG) (κ-CG, ι-CG and λ-CG) was added to skim milk and the rennet-induced aggregation was studied. Caseinomacropeptide (CMP) release, diffusing wave spectroscopy (DWS) and rheology were used to follow the structural dynamics of casein micelles during gelation. The influence of carrageenan on the nature of protein interactions in the gels was investigated using a combination of ultracentrifugation and specific dissociating agents. RESULTS: For the recombined samples containing κ-CG and low concentrations of ι-CG and λ-CG, the CMP release was slowed down; however, the development of DWS and rheological parameters was similar to that of the control sample, and the increase in the incorporation of proteins through calcium bridges and hydrophobic interactions may be the most likely contributors. For the recombined samples containing high concentrations of ι-CG and λ-CG, other factors may impede the gel formation process. CONCLUSION: High concentrations of ι-CG and λ-CG strongly interfered with the rennet-induced aggregation, interrupted the interaction of caseins and therefore may contribute to good quality of low-fat cheese.
BACKGROUND:Carrageenan (CG) (κ-CG, ι-CG and λ-CG) was added to skim milk and the rennet-induced aggregation was studied. Caseinomacropeptide (CMP) release, diffusing wave spectroscopy (DWS) and rheology were used to follow the structural dynamics of casein micelles during gelation. The influence of carrageenan on the nature of protein interactions in the gels was investigated using a combination of ultracentrifugation and specific dissociating agents. RESULTS: For the recombined samples containing κ-CG and low concentrations of ι-CG and λ-CG, the CMP release was slowed down; however, the development of DWS and rheological parameters was similar to that of the control sample, and the increase in the incorporation of proteins through calcium bridges and hydrophobic interactions may be the most likely contributors. For the recombined samples containing high concentrations of ι-CG and λ-CG, other factors may impede the gel formation process. CONCLUSION: High concentrations of ι-CG and λ-CG strongly interfered with the rennet-induced aggregation, interrupted the interaction of caseins and therefore may contribute to good quality of low-fat cheese.