Cheese lipolysis

Kheadr, E. E., J. C. Vuillemard, and S. A. El-Deeb. 2002. Acceleration of Cheddar Cheese Lipolysis by Using Liposome-Entrapped Lipases. Journal of Food Science 67 (2) 485-492. 

Abeijon Mukdsi, M.C., Falentin, H., Maillard, M.B., et al. (2014) The secreted esterase of Propionibacterium freuden-reichii has a major role in cheese lipolysis. Appl Environ Microbiol 80, 751-756. 

Milk from cows affected with mastitis alters the sensory quality of raw milk and cheese (Munro el al., 1984). Sensory defects are reported as increased rancidity and bitterness, factors which are consistent with higher levels of lipolysis and proteolysis (Ma et al., 2000). 

Extensive lipolysis also occurs in Blue cheese varieties in which the principal lipase is secreted by P. roqueforti (Chapter 10). It is claimed that treatment of Blue cheese curd with PGE improves and intensifies its flavour but this practice is not widespread. Several techniques have been developed... 

A good-quality rennet extract is free of lipolytic activity but a rennet paste is used in the manufacture of some Italian varieties, e.g. Romano and Provolone. Rennet paste contains a lipase, referred to as pre-gastric esterase (PGE), which makes a major contribution to lipolysis in, and to the characteristic flavour of, these cheeses. Rennet paste is considered unhygienic and therefore semi-purified PGE may be added to rennet extract for such cheeses (Chapter 8). 

Lipolysis. Some lipolysis occurs in all cheeses the resulting fatty acids contribute to cheese flavour. In most varieties, lipolysis is rather limited (Table 10.5) and is caused mainly by the limited lipolytic activity of the starter and non-starter lactic acid bacteria, perhaps with a contribution from indigenous milk lipase, especially in cheese made from raw milk. 

Extensive lipolysis occurs in two families of cheese in which fatty acids and/or their degradation products are major contributors to flavour, i.e. certain Italian varieties (e.g. Romano and Provolone) and the Blue cheeses. Rennet paste, which contains pre-gastric esterase (PGE) rather than rennet extract, is used in the manufacture of these Italian cheeses. PGE is highly specific for the fatty acids on the sn-3 position of glycerol, which, in the case of milk lipids, are predominantly highly flavoured short-chain fatty acids (butanoic to decanoic). These acids are principally responsible for the characteristic piquant flavour of these Italian cheeses. 

Blue cheeses undergo very extensive lipolysis during ripening up to 25% of all fatty acids may be released. The principal lipase in Blue cheese is that produced by Penicillium roqueforti, with minor contributions from indigenous milk lipase and the lipases of starter and non-starter lactic acid bacteria. The free fatty acids contribute directly to the flavour of Blue cheeses but, more importantly, they undergo partial /J-oxidation to alkan-2-ones (methyl O... 

Proteolysis of casein may be substantial under certain conditions, such as late lactation and mastitic infections. Under these conditions, the number of somatic cells increases. The most noticeable effect of high somatic cell counts is loss of cheese yield. Everson (1984) identified a loss of 0.045 kg of cheese per 45.36 kg of milk for every 106/ml increase of somatic cell count. Somatic cell counts above 4 x 106/ml were also correlated with enhanced lipolysis and with an increased... 

Kristoffersen, T. 1985. Development of flavor in cheese. Milchwissensch 40, 197-199. Kuzdzal-Savoie, S. 1980. Determination of free fatty acids in milk and milk products. In Flavor Impairment of Milk and Milk Products due to Lipolysis. J. H. Moore (Editor). Int. Dairy Fed. Annu. Bull. Doc. No. 118. 

Lipolysis by P. roqueforti is necessary for flavor development in blue-vein cheese. P. roqueforti produces intracellular and extracellular li-... 

Lipolysis Cundida hpobytica C rugosa, Torn lops is sphaerica Mainly in butter, margarine, and cheese. 

Contents I. Introduction 168 II. Sampling Techniques 168 III. Compositional Analysis 169 A. Moisture and total solids 169 B. Fat 171 C. Protein 171 D. Ash 172 E. Salt and chloride content 172 F. Acidity and pH 172 G. Calcium and phosphorus 173 IV. Monitoring Cheese Ripening 173 A. Assessment of lactose, lactate, and citrate metabolism 174 B. Assessment of lipolysis 178 C. Assessment of proteolysis 180 D. Assessment of smaller breakdown products 194 V. Novel and Rapid Instrumental Methods 196 VI. Concluding Remarks 200 References 201... 

Lipolysis is considered to be an important biochemical event during cheese ripening and the current knowledge have been discussed in detail (Collins et al., 2003, 2004 McSweeney and Sousa, 2000). The formation of short-chain FFAs by the lipolysis of milk fat by lipases is a desirable reaction in many cheese types (e.g., mold-ripened cheeses). The catabolism of FFAs, which is a secondary event in the ripening process, leads to the formation of volatile flavor compounds such as lactones, thioesters, ethyl esters, alkanols, and hydroxyl fatty acids. The contributions of lipolysis to the flavor of bacterially ripened cheeses are limited. 

Godinho, M. and Fox, P. F. (1981). Ripening of Blue cheese Influence of salting rate on lipolysis and carbonyl formation. Milckwissenschaft 36,476-478. 

Salji, J. P. and Kroger, M. (1981). Proteolysis and lipolysis in ripening Cheddar cheese made with conventional bulk starter and with frozen concentrated direct-to-the-vat starter culture. ]. Food Sci. 46,1345-1348. 

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

The role of milk-fat in the development of flavor in cheese during ripening will be discussed below although it should not be forgotten that lipolysis and the metabolism of fatty acids do not occur in isolation from other important biochemical events during ripening. 

Figure 11.8. Pathways for the catabolism of free fatty acids in cheese during ripening (reprinted from Cheese Chemistry, Physics and Microbiology, 3rd edn P.F. Fox et al. (eds.), Collins, Y.F., McSweeney, P.L.H., Wilkinson, M.G., Lipolysis and Catabolism of fatty acids in cheese, pp. 373-379, 2004, with permission from Elsevier).

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