Parmesan flavor

Analytical studies of Parmesan flavor have shown that methional, ethyl caproate, and p-cresol give high dilution factors in the isotope dilution analysis of the flavor extract and, hence, represent important constituents of this type of cheese. 

Free glutamates exist in certain cheeses (such as parmesan), in tomato products, and in soy sauce. These products are often used to enhance the flavor of meat dishes. Proteins can be hydrolyzed by heat, releasing free glutamates. Cooked meats, especially grilled meats, get some of their taste from free glutamates. 

Parmesan or Grana, as it is known in Italy, is a group of very hard bacteria-ripened, granular-textured cheeses made from partially skimmed cow s milk. They originated in Parma, near Emilia, Italy, hence the name. Special lipolytic enzymes derived from animals are used, in addition to rennet, to produce the characteristic rancid flavor. 

Lipolysis is considered to be undesirable in most cheese varieties. Cheddar, Gouda, and Swiss-type cheeses containing even a moderate level of free fatty acids would be considered rancid however, certain cheese varieties are characterized by extensive lipolysis (e.g., Romano, Parmesan, and Blue cheeses). Bills and Day (1964) quantified FFA ( 2 0 to Cj8 3) in 14 Cheddar cheeses with wide variations in flavor but found only small differences, qualitatively or quantitatively, between cheeses of different flavor. The... 

A more comprehensive study on Cheddar, Gouda, Edam, Swiss, and Parmesan (total of 82 samples) was reported by Aishima and Nakai (1987). The volatiles were extracted by CH2CI2 and analyzed by GC. More than 200 peaks were resolved in every chromatogram, 118 of which were selected as variables for discriminative analysis. Expression of the area of each of the 118 peaks as a percentage of total chromatogram area clearly permitted classification of the five varieties. The compounds likely to be responsible for the characteristic flavor of each variety were not discussed. 

Cheese ripening is a slow, and hence an expensive, process, e.g., Parmesan and extramature Cheddar are ripened for at least 18 months. Ripening is still not controllable precisely, i.e., the quality and intensity of flavor cannot be predicted precisely. Therefore, there is an economic incentive for the development of methods for the acceleration of cheese ripening, provided that the flavor and texture can be maintained and characteristic of the variety. 

Enzymatically modified cheeses developed to accelerate the ripening and flavor building blocks can be produced by controlled proteolytic and/or lipolytic enzyme treatment of natural cheese. The most popular enzyme-modified cheeses include Cheddar, Swiss, Parmesan, Romano, Brick, and Blue cheeses [95]. 

For quantitative determination of these flavor compounds, 400 g of grated Parmesan cheese was quick-frozen with liquid nitrogen and then ground to a fine powder. The powdered cheese was extracted overnight with dichloromethane containing 50 pg of the internal standard [ Hsl-methional, 400 ig of [ Hsl-ethyl caproate, and 4 pg of pHv]-p-cresol. The volatile compounds were distilled from... 

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