Blue cheese flavor

Tomasini, A., Bustillo, G., Lebeault, J.M. 1993, Fat lipolysed with a commercial lipase for the production of Blue cheese flavor. Int. Dairy J. 3, 117-127. 

Both the spores and the mycelium seem capable of producing methyl ketones from fatty acids (12, 13). Furthermore, both short chain and long chain fatty acids are metabolized, thereby giving rise to an homologous series of methyl ketones, the main ones being 2-pentanone, 2-heptanone and 2-nonanone (14). A number of processes have been developed and patented for producing blue cheese flavor via the fermentation of milk fat (15, 16). Usually the... 

Blue cheese flavors have been prepared via submerged culture fermentations in a sterile milk-based medium using Penicillium rogueforti(63). The fermentations are conducted under pressure with low aeration rates with optimal flavor production occurring from 24-72 hours. Similarly, Kosikowski and Jolly(64) prepared blue cheese flavors from the fermentation of mixtures of whey, food fat, salt and water by P roqueforti. Dwivedi and Kinsella(65) developed a continuous submerged fermentation of P. roqueforti for production of blue cheese flavor. 

Lactones have very low flavor thresholds (Kinsella et al, 1965). Jolly and Kosikowski (1975b) found that the concentration of lactones in Blue cheese was higher than that in Cheddar and concluded that the extensive lipolysis in Blue cheese influences the formation of lactones 5-Ci4 and 5-C16 were the principal lactones in Blue cheese (as found also for Cheddar) (Wong et al, 1973). A stronger typical Blue cheese flavor was found in cheeses containing added lipase, perhaps because lactones blend or modify harsher flavors. 

Traditionally fermented dairy products have been used as beverages, meal components, and ingredients for many new products [60], The formation of flavor in fermented dairy products is a result of reactions of milk components lactose, fat, and casein. Particularly, the enzymatic degradation of proteins leads to the formation of key-flavor components that contribute to the sensory perception of the products [55], Methyl ketones are responsible for the fruity, musty, and blue cheese flavors of cheese and other dairy products. Aromatic amino acids, branched-chain amino acids, and methionine are the most relevant substrates for cheese flavor development [55]. Volatile sulfur compounds derived from methionine, such as methanethiol, dimethylsulflde, and dimethyltrisul-fide, are regarded as essential components in many cheese varieties [61], Conversion of tryptophan or phenylalanine can also lead to benzaldehyde formation. This compound, which is found in various hard- and soft-type cheeses, contributes positively to the overall flavor [57,62]. The conversion of caseins is undoubtedly the most important biochemical pathway for flavor formation in several cheese types [62,63]. A good balance between proteolysis and peptidolysis prevents the formation of bitterness in cheese [64,65],... 

The use of homogenized milk for cheesemaking has been reviewed by Peters (1964). The advantages of homogenized milk in the manufacture and ripening of cheese are (1) lower fat losses in whey and therefore a higher yield, (2) reduced fat leakage of cheese at room temperatures, and (3) increased rate of fat hydrolysis and, therefore, desired flavor production in blue cheese. 

The flavor of blue cheese is produced by a combination of free fatty acids and methyl ketones derived from fatty acids. The partial oxidation of fatty acids to methyl ketones occurs via the /3-oxidation pathway (Kinsella and Hwang 1976A). 

In some mold-ripened cheeses, a very high FFA content (up to 25% of total fatty acids Gripon, 1987) is acceptable [e.g., >66 000 mg/kg for Blue cheese (Horwood et al., 1981) compared to <4000 mg/kg for good quality Cheddar (Bills and Day, 1964)]. High levels of butyric acid characterise Italian hard cheeses and certain pickled cheeses (Fox and Guinee, 1987), [e.g., up to 520 mg/kg for Greek Feta (Horwood et al., 1981) and >3000 mg/ kg for Romano (Woo and Lindsay, 1984)]. An imbalance in flavor constituents can, nevertheless, lead to undesirably rancid or goaty (C4 o-C8 0) or soapy (Cio o-Ci2 o) flavors in these cheeses (Woo and Lindsay, 1984). 

Jolly, R.C., Kosikowski, F.V. 1975a. Flavor development in pasteurized milk blue cheese by animal and microbial lipase preparations. J. Dairy Sci. 58, 846-852. 

The hydrolysis of triglycerides in cheese is an example of a desirable flavor-producing process. The extent of free fatty acid formation is much higher in blue cheese than in Cheddar cheese, as is shown in Table 10-3. This is most likely the result of lipases elabo-... 

The flavor is fruity-red fruit, gooseberry, slightly blue cheese (Chemisis, 1993),... 

The odor is unpleasant with a nutty, blue-cheese, plastic, machine oil and raw mushroom flavor (Chemisis, 1998). 

Extensive lipolysis occurs in mould-ripened cheese, particularly blue varieties. In some cases, up to 25% of the total FFA may be liberated (see Gripon, 1987, 1993). However, the impact of FFA on the flavor of blue mould-ripened cheeses is less than in hard Italian varieties, possibly due to neutralization as the pH increases during ripening and to the dominant influence of methyl ketones on the flavor of blue cheese. 

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... 

Undoubtedly, the products of these primary biochemical events, i.e., fatty and other acids, peptides, and amino adds, contribute to cheese flavor, perhaps very significantly in many varieties and proteolysis certainly has a major influence on the various rheological properties of cheese, e.g., texture, meltability, and stretchability. However, the finer points of cheese flavor are almost certainly due to further modification of the products of the primary reactions. The most clear-cut example of this is the oxidation of fatty acids to methyl ketones in blue cheeses. Catabolism of amino acids leads to the production of numerous sapid compounds, including amines, carbonyls, acids, thiols, and alcohols. Many of these compounds may interact chemically with each other and the compounds of other reactions via the Maillard and Strecker reactions. At present, relatively little is known concerning the enzymology of amino acid catabolism in most cheeses and even less is known about the chemical reactions. It is very likely that research attention will focus on these secondary and tertiary reactions in the short-term future. 

Patton, S. (1950). The methyl ketones of Blue cheese and their relation to its flavor. J. Dairy Scl 33, 680-684. 

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]. 

The bioflavor compounds of blue cheese, obtained from fermentation of Aspergillus spp., were encapsulated in soy lecithin liposomes and spray-dried to obtain the powder form by Santana et al. (2005). A sensory evaluation was performed, by adding the liposome-bioflavor powder in a base of light cream cheese, which was spread on toasts. Flavor intensity, acceptance by the consumers, and purchasing intention were the tests done in the sensory evaluation. The results showed that the encapsulation maintained the characteristic flavor of blue cheese and the product was classified by the consumers as acceptable. The dried liposome-stabilized flavor was useful to add in foods and to be kept in storage. 

There is evidence that among the fatty acids only butyric and caproic acids 42), at sub-threshold concentrations, interact to contribute to the desirable butter flavor 367). A whole set of fatty acids provide a background flavor in the case of Cheddar cheese. Propionic acid is an essential flavor component in Swiss cheese 330). The characteristic flavor of blue cheese, however, is due to the presence of aliphatic methyl-ketones 161, 308). 

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