Hostname: page-component-76fb5796d-qxdb6 Total loading time: 0 Render date: 2024-04-26T19:01:23.812Z Has data issue: false hasContentIssue false

Effect of proteolytic raw milk psychrotrophs on Cheddar cheese-making with stored milk

Published online by Cambridge University Press:  01 June 2009

Barry A. Law
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
Anthony T. Andrews
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
Allan J. Cliffe
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
M. Elisabeth Sharpe
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT
Helen R. Chapman
Affiliation:
National Institute for Research in Dairying, Shinfield, Reading, RG2 9AT

Summary

The effect of proteolytic, psychrotrophic strains of Pseudomonas fluorescens, Ps. putida and Acinetobacter spp. on cheese-making with stored milk has been investigated. Ps. fluorescens and Ps. putida growing for 72 h in raw milk at 7·5 °C to levels of approx. 107 colony-forming units/ml caused a low degree of β- and к-casein breakdown detectable by gel electrophoresis, but this was insufficient to affect N losses in whey or cheese yields. Variations in cheese-making times with pasteurized milks were not attributable to the counts of psychrotrophs in the corresponding raw milks. The water-soluble and TCA-soluble N fractions of maturing cheeses were unaffected by psychrotroph counts in raw milks, but small differences in levels of casein fractions of cheeses made from milks stored for 72 h were detected by quantitative polyacrylamide gel electrophoresis. The incidence of casein breakdown in raw milk and subsequently in cheese were not necessarily related. None of the cheeses developed off flavour related to excessive protein breakdown but many became lipolytically rancid, despite the selection of strains with low lipolytic activity on a diagnostic medium. It is concluded that the numbers of psychrotrophic bacteria likely to occur in stored raw milk under commercial conditions are unlikely to cause significant changes in the yields or quality of Cheddar cheese through their proteolytic activity.

Type
Original Articles
Copyright
Copyright © Proprietors of Journal of Dairy Research 1979

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Alichanidis, E. & Andrews, A. T. (1977). Biochimica et Biophysica Acta 485, 424.CrossRefGoogle Scholar
Anderson, M. & Andrews, A. T. (1977). Journal of Dairy Research 44, 223.CrossRefGoogle Scholar
Aschaffenburg, R. & Michalak, W. (1968). Journal of Dairy Science 51, 1849.CrossRefGoogle Scholar
Chapman, H. R., Sharpe, M. E. & Law, B. A. (1976). Dairy Industries International 41, 42.Google Scholar
Cousin, M. A. & Marth, E. H. (1977). Journal of Dairy Science 60, 1048.CrossRefGoogle Scholar
Feuillat, M., Le Guennec, S. & Olsson, A. (1976). Lait 56, 521.CrossRefGoogle Scholar
Harrigan, W. F. & Mccance, M. E. (1976). Laboratory Methods in Food and Dairy Microbiology. New York: Academic Press.Google Scholar
Hendrie, M. S. & Shewan, J. M. (1966). Technical Series, Society for Applied Bacteriology 1, 1Google Scholar
Juffs, H. S. (1974). Australian Journal of Dairy Technology 29, 74.Google Scholar
Law, B. A., Andrews, A. T. & Sharpe, M. E. (1977). Journal of Dairy Research 44, 145.CrossRefGoogle Scholar
Law, B. A., CastañóN, M. & Sharpe, M. E. (1976a). Journal of Dairy Research 43, 117.CrossRefGoogle Scholar
Law, B. A., CastañóN, M. & Sharpe, M. E. (1976b). Journal of Dairy Research 43, 301.CrossRefGoogle Scholar
Law, B. A., Cousins, C. M., Sharpe, M. E. & Davies, F. L. (1979). Technical Series, Society for Applied Bacteriology 13 (In the Press.).Google Scholar
Law, B. A., Sharpe, M. E. & Chapman, H. R. (1976C). Journal of Dairy Research 43, 459.CrossRefGoogle Scholar
Law, B. A., Sharpe, M. E., Mabbitt, L. A. & Cole, C. B. (1973). Technical Series, Society for Applied Bacteriology 7, 1.Google Scholar
O'Keeffe, R. B., Fox, P. F. & Daly, C. (1976). Journal of Dairy Research 43, 97.CrossRefGoogle Scholar
Olson, N. F. (1977). Dairy Industries International 42, 14.Google Scholar
Price, W. V. (1952). Cheese. New York: Orange Judd Publishing Co. Inc.Google Scholar
Reimerdes, E. H. & Klostermeyer, H. (1976). Methods in Enzymology 45, 26.CrossRefGoogle Scholar
Reiter, B., Fryer, T. F. & Sharpe, M. E. (1965). Journal of Dairy Research 32, 89.CrossRefGoogle Scholar
Shewan, J. M., Hobbs, G. & Hodgkiss, W. (1960). Journal of Applied Bacteriology 23, 379.CrossRefGoogle Scholar
Stanier, R. Y., Palleroni, N. J. & Doudoroff, M. (1966). Journal of General Microbiology 43, 159.CrossRefGoogle Scholar
Visser, F. M. W. & De Groot-Mostert, A. E. A. (1977). Netherlands Milk and Dairy Journal 31, 247.Google Scholar
Yates, A. R. & Elliot, J. A. (1977). Canadian Institute of Food Science and Technology Journal 10, 269.CrossRefGoogle Scholar