Monitoring Proteolysis During Ripening of Full‐fat and Low‐fat Cheddar Cheeses by Reverse‐Phase HPLC

Abstract

Proteolysis during ripening of full-fat and low-fat Cheddar cheese was investigated by applying reverse-phase HPLC to the pH 4.6 water-soluble N fraction of cheese. The separated N compounds were divided into four MW ranges. The number of separated peaks and the amount of N compounds separated in each of the MW ranges increased with ripening time. Significant within-cheese, within-variety, and betweenvarieties differences in the amounts and proportions of N compounds with different MW were observed as related to ripening time. Reversephase HPLC of the pH 4.6 water-soluble N fraction of cheese can provide detailed quantitative information on proteolytic activities during ripening.

Composition and Sensory Attributes of Retail Cheddar Cheese with Different Fat Contents

“…However, the mean levels of pH4.6SN (as % total N) decreased numerically in the order: FF'HF'RF, while PTAN and total FAA decreased numerically in the order: HF'RF'FF. These trends are similar to those reported by Altemueller and Rosenberg (1996) who showed that commercial full-fat cheeses, ripened at 53C, had numerically higher levels of water-soluble nitrogen Values without a common superscript were signi"cantly di!erent (P(0.05). Groups designated: HF, half-fat; RF, reduced-fat; FF, full-fat.…”

“…The general increase in the proportions of peptides (as a percentage of total nitrogenous material) as their MM decreased concurs with the general held view that proteolysis in Cheddar type cheeses involves the sequential hydrolysis of large casein-derived peptides (e.g., '10 kDa) to peptides of ever-decreasing MM and eventually to FAA, with ripening time Altemueller and Rosenberg, 1996). Similar to the trend obtained for nitrogen solubility and total FAA, the MM distribution of peptides by GP-HPLC was not signi"cantly a!ected by inter-group variation in fat level.…”

Proteolysis of Fynbo Cheese Salted with NaCl/KCl and Ripened at Two Temperatures

“…The increase of WSN was faster during the first 30 ripening days of cheeses S and K reaching 66% of the 90 day value at 12ЊC and about 60% at 16ЊC. These results could probably be attributed to the breakdown of caseins, mainly ␣ s1 -casein, developed in the early stages of ripening, with a higher reaction rate than the others (Altemueller and Rosenberg, 1996).…”

“…These results could probably be attributed to the breakdown of caseins, mainly ␣ s1 -casein, developed in the early stages of ripening, with a higher reaction rate than the others (Altemueller and Rosenberg, 1996).…”

Accelerated Cheddar Cheese Ripening with an Aminopeptidase Fraction from Squid Hepatopancreas

“…Accumulation of peptides during ripening of Cheddar cheese was investigated by the use of reverse-phase HPLC, using the method described by Altemueller and Rosenberg (1996). Grated cheese (200 g) was blended with 400 mL water, and pH was adjusted to 4.6 by adding HCl.…”