Flavor cheese

Aliphatic monoketones are of minor importance as fragrance and aroma substances. 2-Alkanones (C3-C15) have been found in the volatile fractions of many fruits and foodstuffs, but they do not contribute signiflcantly to their aroma. An exception are the odd-numbered methyl ketones Cy, C9, Cn which possess a characteristic nutty note they are used, e.g., in cheese flavor compositions. In... 

Straight-chain, saturated aliphatic acids are found in many essential oils and foods. These acids contribute to aromas, but are not important as fragrance substances. In flavor compositions, aliphatic acids up to Cio are used to accentuate certain aroma characteristics (C3-C8 for fruity notes C4, C6-C12 for cheese flavors). However, straight-chain and some branched-chain aliphatic acids are of... 

Amino acids are generally not considered to be important flavor components of several varieties of cheese, although they are important precursors of a variety of flavor components volatile sulfur compounds, amines, aldehydes, and ammonia (Adda et al. 1982 Aston and Dulley 1982 Forss 1979 Langsrud and Reinbold 1973). Free proline levels in Swiss cheese are important in producing the typical sweet cheese flavor. Cheeses with a proline content of < 100 mg/100 g cheese lacked the sweet flavor, while levels of >300 mg/100 g produced a cheese of excessive sweetness (Mitchell 1981). 

Aston, J. W. and Dulley, J. R. 1982. Cheddar cheese flavor. Aust. J. Dairy Technol. 37, 59-64. 

Micrococci comprise approximately 78% of the nonlactic bacteria in raw milk Cheddar cheese (Alford and Frazier 1950). The proteolytic system of Micrococcus freudenreichii functions optimally at 30 °C and at a pH near neutrality (Baribo and Foster 1952). An analysis of pro-teinases present in 1-year-old Cheddar cheese indicates that micrococci may contribute to proteolytic activity (Marth 1963). Proteolytic micrococci also contribute to the ripening of surface-ripened cheeses such as brick and Camembert (Lenoir 1963 Langhus et al. 1945). Micrococcal proteases probably contribute to development of ripened cheese flavor when ripening temperatures are above 10°C (Moreno and Kosikowski 1973). This effect results from degradation of /3-casein. 

Dacre, J. C. 1953. Cheddar cheese flavor and its relation to tyramine production by lactic acid bacteria. J. Dairy Res. 20, 217-223. 

Kinsella, J. E. and Hwang, D. H. 1976B. Enzymes of Penicillium roqueforti involved in the biosynthesis of cheese flavor. Crit. Rev. Food Sci. Nutr. 8, 191-228. 

Proteolysis is the most important of the three primary events occurring during cheese ripening. Due to the complexity of proteolysis, including the catabolism of amino acids and their contribution to cheese flavor, this topic has been the focus of several studies. A comprehensive review of the... 

Free amino acids are further catabolized into several volatile flavor compounds. However, the pathways involved are not fully known. A detailed summary of the various studies on the role of the catabolism of amino acids in cheese flavor development was published by Curtin and McSweeney (2004). Two major pathways have been suggested (1) aminotransferase or lyase activity and (2) deamination or decarboxylation. Aminotransferase activity results in the formation of a-ketoacids and glutamic acid. The a-ketoacids are further degraded to flavor compounds such as hydroxy acids, aldehydes, and carboxylic acids. a-Ketoacids from methionine, branched-chain amino acids (leucine, isoleucine, and valine), or aromatic amino acids (phenylalanine, tyrosine, and tryptophan) serve as the precursors to volatile flavor compounds (Yvon and Rijnen, 2001). Volatile sulfur compounds are primarily formed from methionine. Methanethiol, which at low concentrations, contributes to the characteristic flavor of Cheddar cheese, is formed from the catabolism of methionine (Curtin and McSweeney, 2004 Weimer et al., 1999). Furthermore, bacterial lyases also metabolize methionine to a-ketobutyrate, methanethiol, and ammonia (Tanaka et al., 1985). On catabolism by aminotransferase, aromatic amino acids yield volatile flavor compounds such as benzalde-hyde, phenylacetate, phenylethanol, phenyllactate, etc. Deamination reactions also result in a-ketoacids and ammonia, which add to the flavor of... 

Manning, D. J. (1978). Cheddar cheese flavor studies I. Production of volatiles and development of flavor during ripening.. Dairy Res. 45,479-490. 

Yvon, M. and Rijnen, L. (2001). Cheese flavor formation by amino acid catabolism. Int. Dairy J. 11,185-201. 

Yvon, M., Thirouin, S., Rijnen, L., Fromentier, D., and Gripon, J. C. (1997). An aminotransferase from Lactococcus lactis initiates conversion of amino acids to cheese flavor compounds. Appl. Environ. Microbiol. 63, 414-419. 

Smit, G., Verheul, A., van Kranenburg, R., Ayad, E., Siezen, R., and Engels, W. 2000. Cheese flavor development by enzymatic conversions of peptides and amino acids. Food Res. Int. 33, 153-160. 

Contribution of Lipolysis and Catabolism of Free Fatty Acids (FFA) to Cheese Flavor... 

Acting as a source of fatty acids, which when liberated from triacyl-glycerols by the action of lipases, contribute directly to cheese flavor... 

In addition to their direct role in cheese flavor, FFAs also act as precursors for a range of other volatile flavor compounds such as K-methyl ketones (alkan-2-ones), secondary alcohols, hydroxyacids, lactones, esters, and thioesters (Collins et al., 2003a, 2004 McSweeney, 2004). General pathways though which FFAs are catabolised are shown in Figure 8. 

Arbige, M.V., Freund, P.R., Silver, S.C., Zelko, J.T. 1986. Novel lipase for Cheddar cheese flavor development. Food Technol. 40(4), 91-96, 98. 

Chapman, H.R., Sharpe, M.E., Law, B.A. 1976. Some effects of low-temperature storage of milk on cheese production and Cheddar cheese flavor. Dairy Ind. Int. 41, 42-45. 

Huang, H.T., Dooley, J.G. 1976. Enhancement of cheese flavors with microbial esterases. Biotechnol. Bioeng. 18, 909-919. 

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. 

Korycka-Dahl, M., Vassal, L., Ribadeau Dumas, B., Mocquot, G. 1983. Studies on lipid oxidation during ripening of Camembert cheese and its impact on cheese flavor. Sci. Alim. 3, 79-90. 

Odor-active components in cheese flavor, many of which are derived from milk lipids, can be detected using GC-olfactometry (GC-O). GC-0 is defined as a collection of techniques that combine olfactometry, or the use of the human nose, as a detector to assess odor activity in a defined air stream post-separation using a GC (Friedich and Acree, 1988). The data generated by GC-0 are evaluated primarily by aroma extract dilution analysis or Charm analysis. Both involve evaluating the odor activity of individual compounds by sniffing the GC outlet of a series of dilutions of the original aroma extract and therefore both methods are based on the odor detection threshold of compounds. The key odourants in dairy products and in various types of cheese have been reviewed by Friedich and Acree (1988) and Curioni and Bosset (2002). 

Three illustrations are used to review the various approaches taken by the enzyme industry in tailoring enzyme preparations to meet the production and product quality needs of the food industry. Tailored enzyme preparations have been able to convert the corn syrup industry from an acid-based industry to an enzyme-based industry, to overcome the problems created in the baking industry as grain technology improved and automation was introduced, and to rescue the cheese industry as the supply of bovine rennet decreased and the demand for cheese and cheese flavor increased. 

When there is a need, someone will solve it. A patent was issued in 1987 (22) describing a new and novel lipase produced by a mutant strain of Aspergillus that has an accelerating effect on cheese flavor development without lypolytic enzyme associated rancidity. The patent claims that this new lipase will be useful as a ripening accelerator in the production of mild flavored cheeses such as cheddar. 

Today, cheese flavored paste and powders, containing from 5 to 100 times the flavor level of native cheese, are available in the marketplace for most cheese varieties. Nearly all of these products are made by using added enzymes with most of them using a blend of enzymes and microorganisms. Selected cheese flavors are produced in a liquid or slurry form in a relatively short time compared to making the true cheese and at a flavor level many fold above the maximum flavor obtainable in the true cheese. 

Cheese/hutter flavor. Pregastric lipases, have, been used for years to intensify flavor in Menzyme-modified cheese , and for an intensified butter flavor in lipolyzed butter. Generally the fatty acid residues that need to be split off (to generate the right flavor) are the short chain fatty acids, especially the C to C-jq acids typical of Italian cheeses. The butyric acids are produced from butterfat more specifically by newly developed lipases (really esterases) from Mucor meihei and a very new one, from Aspergillus oryzae, especially for cheddar cheese flavor development. The latter enzyme is marketed under the name Flavor Age (4). Flavors produced in this manner are used widely in cheese-flavored snack foods the value of the intensified cheese flavors is on the order of 50 million, but the. value of the enzymes employed is only about 2-3 million. 

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