Enzymes of penicillium roqueforti involved in the biosynthesis of cheese flavor

Abstract

The ripening of blue and Roquefort cheeses is accomplished by the concerted and controlled actions of enzymes of the mold Penicillium roqueforti. The properties and effects of the enzymes involved in flavor development (i.e., proteases, lipase and beta-ketoacid decarboxylase) are reviewed. The metabolic activities of both spores and mycelia of P. roqueforti in relation to fatty acid metabolism and flavor generation are discussed. The chemical composition of blue cheese flavor and the simulation of this flavor by fermentation and formulation are briefly surveyed. Some nutritional aspects of blue cheese are cited.

Accelerated production of blue cheese flavors by fermentation on granular curds with lipase addition

“…The substrate proved to be adequate for the 4 strains studied, which follow the same evolution pattern but differ in nitrogen solubilization, FFA and methyl-ketones production rates. Under the studied conditions, the product did not develop a «rnoldy» flavor as was reported by Kinsella and Hwang (1976) for the assays realized by Kondrup and Hedrick (1963) with a divided curd for blue cheese flavor production.…”

“…A marked reduction in the total carbonyls concentration was generally observed towards the end of the fermentation. This observation may be attributed mainly to 2 factors : the evaporation losses promoted by the high surface of the granular curds and to the transformation of the methylketones into secondary alcohols by the mold (Kinsella and Hwang, 1976). Beyond 160 h the product has a strong ammoniacal odor, a very unpleasant soapy flavor and a cream-like texture.…”

“…The typical flavor constituents are the methyl-ketones, especially 2-heptanone, which are produced by the beta-oxydation of the free fatty acids (FFA) (Kinsella and Hwang, 1976). This transformation, which is believed to be a way to diminish the FFA inhibition, is caused by the mycelium and the spore of the mold.…”

Cloning, Characterization, Controlled Overexpression, and Inactivation of the Major Tributyrin Esterase Gene of Lactococcus lactis

“…The contribution of the native milk lipase to lipolysis in cheese is significant only in those varieties produced with raw milk, as this enzyme is inactivated during heat treatment. In soft blue-veined cheeses, the extracellular lipase from the mold Penicillium roquefortii contributes to the intense and characteristic flavor (26). In other varieties, like cheddar cheese, only a low level of milk fat hydrolysis occurs due to the weak lipolytic and esterolytic activities of the starter bacteria (7,37).…”

Lipolysis in Picante cheese: Influence of milk type and ripening time on free fatty acid profile

“…Lipolysis is a biochernical phenomenon of great importance; anaIysis of the profile of short and medium chain (i.e., C 4 -C I2 ) free fatty acids (FFA) is often used in the chemical characterization of the extent of chee se ripening [4,12,19] because such FFA make significant contributions to the flavor of different types of cheese. Furthermore, FF A also act as precursors for chemical formation of such other important aroma components as esters, aldehydes, and ketones [10,17].…”