Proteolysis during aging of commercial full-fat and reduced-fat Cheddar cheeses of identical chronological age

The evolution of Cheddar cheese flavor and texture is highly dependent on its proteolytic state however, Cheddar cheese is marketed based on its chronological age. Information about the proteolytic age of commercial Cheddar cheese of a given age almost does not exist. The present research challenged the merit of marketing Cheddar cheese according to its chronological age. Full -fat (FF) and Reduced-fat (RF) Cheddar cheeses, of identical chronological age, were aged for 180 days at 5 celcius and the progression of the proteolytic cascade was investigated and quantified. The accumulation of the cheese N fractions that are soluble at pH 4.6 (4.6SN), soluble in 12% tri-chloroacetic acid (12TCASN), and soluble in 5% phospho-tungstic acid (5PTASN) was quantified along with the accumulation of free L-Glutamic acid (L-Glu). Results indicated that both FF and RF cheeses exhibited very significant among-cheeses differences in accumulation of the investigated fractions (p < 0.05). These significant differences were related to both the concentration of the fractions and the rate at which they accumulated. The results thus reflected significant among-cheeses differences in the inherent proteolytic potential of the cheeses as well as in its manifestation during aging. Results clearly indicated that the chronological age of the investigated cheeses did not reflect their proteolytic age. The results highlighted the need to market Cheddar cheese based on some proteolysis-related quantitative parameters.