71A-39 |
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L. ONG1, N. P. Shah1, and A. Henriksson2. (1) School of Molecular Sciences, Victoria Univ., Werribee Campus, PO Box 14428, Melbourne City Mail Centre, Melbourne, Victoria, 8001, Australia, (2) Research and Development, DSM Food Specialties, 9 Moorebank Avenue, Moorebank, New South Wales, 2170, Australia Incorporation of probiotic cultures in Cheddar cheeses has been reported to provide health benefits to consumers. Careful selection of strains, however, is required for their survival during manufacturing and ripening periods. Addition of probiotic adjuncts may also influence the proteolytic pattern, which is one of the factors that determines Cheddar cheese quality and flavor profile. Our objectives were to study (1) the survivability of probiotic organisms in Cheddar cheeses, and (2) the influence of these organisms on proteolytic patterns and production of organic acid. Cheddar cheeses were made with starter lactococci and various combinations of probiotic bacteria. Probiotic, starter, and nonstarter lactic acid bacteria were enumerated using selective media at monthly intervals. Concentration of organic acid was analyzed using HPLC. Proteolytic patterns were examined using SDS-PAGE and soluble nitrogen method. All probiotic adjuncts survived the manufacturing process and maintained viability of > 7.5 log10 CFUg-1 at the end of ripening for 6 mo at 4 °C. Lactococci counts decreased by one to two log cycles. No significant differences (P > 0.05) were observed in fat, protein, moisture, and salt contents, but acetic acid concentration was higher in probiotic cheeses. Primary proteolysis was not significantly different (P > 0.05) between cheeses, but secondary proteolysis as indicated by concentration of free amino acids was significantly higher (P < 0.05) in probiotic cheeses. Hydrolysis of casein after 6 mo of storage was higher in probiotic cheeses with preference over αs-CN than β-CN. As the concentrations of casein decreased, concentration of lower molecular weight breakdown products of the caseins increased. Proteolytic activity, however, remained low for all cheeses due to low temperature of storage. Our results indicated that the addition of probiotic microorganisms in Cheddar cheeses increased proteolytic activity and changed flavor profile. Results also demonstrated that Cheddar cheese can be an effective vehicle for delivery of some health-promoting bacteria to the consumer.
Session 71A, Dairy Foods: General
2005 IFT Annual Meeting, July 15-20 - New Orleans, Louisiana |