Czech J. Food Sci., 2016, 34(4):306-312 | DOI: 10.17221/64/2016-CJFS

Proteolysis in raw milk in relation to microbiological indicatorsFood Analysis, Food Quality and Nutrition

Jana Chramostová, Oto Hanuš, Marcela Klimešová, Irena Němečková, Petr Roubal, Jaroslav Kopecký, Radoslava Jedelská, Ludmila Nejeschlebová
Dairy Research Institute, Prague, Czech Republic

Proteolysis in raw milk is a crucial parameter indicating both cow's mastitis and the technological problems or spoilage risk of final products. However, a suitable analytical method for its early detection in practice is still missing. Thus, we proposed a spectrophotometric determination of milk proteolysis equivalent (MPE). We tested this method on 104 bovine raw milk samples in relation to their somatic cell count (SCC) as an indicator of native proteolysis, and the total count of mesophilic bacteria (TCMB) and the total count of psychrotrophic bacteria (TCPB) as indicators of microbial proteolysis. Correlation coefficients between log TCMB and MPE and log TCPB and MPE were 0.3651 and 0.4152, respectively (both P < 0.001). SCC was not correlated with MPE (P > 0.05). We estimated the MPE limit indicating an incipient risk of proteolysis in the range from 0.9366 to 1.02 mmol/l. The determination of MPE seems to be a promising method applicable in the control of raw milk.

Keywords: primary amino groups; proteolytic enzymes; psychrotrophic microorganisms; quality of bovine raw milk; somatic cell count; total count of microorganisms

Published: August 31, 2016  Show citation

ACS AIP APA ASA Harvard Chicago Chicago Notes IEEE ISO690 MLA NLM Turabian Vancouver
Chramostová J, Hanuš O, Klimešová M, Němečková I, Roubal P, Kopecký J, et al.. Proteolysis in raw milk in relation to microbiological indicators. Czech J. Food Sci. 2016;34(4):306-312. doi: 10.17221/64/2016-CJFS.
Download citation

References

  1. Barbano D.M. (2000): Practical Guide for Control of Cheese Yield. Brussels, International Dairy Federation: 19-27.
  2. Chramostová J., Rubina N., Šedivcová V., Dragoun M., Němečková I., Roubal P. (2014): Vliv chladírenských teplot na růst a proteolytickou činnost mikroorganismů syrového mléka. Mlékařské listy - Zpravodaj, 146: 10-13.
  3. Coulon J.B., Gasqui P., Barnouin J., Ollier A., Pradel P., Pomiès D. (2002): Effect of mastitis and related-germ on milk yield and composition during naturally-occurring udder infections in dairy cows. Animal Research, 51: 383-393. Go to original source...
  4. Čurda L., Dryáková A. (2003): Modification of spectrophotometrical method for the determination of primary amino-groups in milk proteins. In: Proceedings of National Cheese Competition, Jan 22, 2003, Prague, Czech Republic: 124-128.
  5. Datta N., Deeth H.C. (2003): Diagnosing the cause of proteolysis in UHT milk. LWT-Food Science and Technology, 36: 173-182. Go to original source...
  6. Gaucher I., Mollé D., Garnaire V., Gaucheron F. (2008): Effects of storage temperature on physico-chemical characteristics of semi-skimmed UHT milk. Food Hydrocolloids, 22: 130-143. Go to original source...
  7. Hanuš O., Janů L., Schuster J., Kučera J., Vyletělová M., Genčurová V. (2011): Exploratory analysis of dynamics of frequency distribution of raw cow milk quality indicators in the Czech Republic. Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis, 59: 83-100. Go to original source...
  8. Janů L., Hanuš O., Frelich J., Macek A., Zajíčková I., Genčurová V., Jedelská R. (2007): Influences of different milk yields of Holstein cows on milk quality indicators in the Czech Republic. Acta Veterinaria Brno, 76: 553-561. Go to original source...
  9. Le T.X., Datta N., Deeth H.C. (2006): A sensitive HPLC method for measuring bacterial proteolysis and proteinase activity in UHT milk. Food Research International, 39: 823-830. Go to original source...
  10. Le Bars D., Gripon J.C. (1993): Hydrolysis of αs1-casein by bovine plasmin. Le Lait, 73: 337-344. Go to original source...
  11. Le Roux Y., Colin O., Laurent F. (1995): Proteolysis in samples of quarter milk with varying somatic cell counts. 1. Comparison of some indicators of endogenous proteolysis in milk. Journal of Dairy Science, 78: 1289-1297. Go to original source... Go to PubMed...
  12. McKellar R.C. (1981): Development of off-flavours in ultrahigh temperature and pasteurized milk as a function of proteolysis. Journal of Dairy Science, 64: 2138-2145. Go to original source...
  13. McSweeney P.L.H., Fox P.F., Olson N.F. (1995): Proteolysis of bovine caseins by cathepsin D: preliminary observations and comparison with chymosin. International Dairy Journal, 5: 321-336. Go to original source...
  14. Němečková I., Pechačová M., Roubal P. (2009): Problems with the detection of proteolytic micro-organisms and their undesirable activities in milk. Czech Journal of Food Sciences, 27 (Special Issue 2): S2-82-S2-89. Go to original source...
  15. Özer B.H. (2000): Microbiology of liquid milk. In: Robinson R.K., Batt C.A., Patel P.D. (eds): Encyclopaedia of Food Microbiology. London, Academic Press: 1436-1440. Go to original source...
  16. Topcu A., Numanoglu E., Saldamli I. (2006): Proteolysis and storage stability of UHT milk produced in Turkey. International Dairy Journal, 16: 633-638. Go to original source...
  17. Upadhyay V.K., McSweeney P.L.H., Magboul A.A.A., Fox P.F. (2004): Proteolysis in cheese during ripening. In: Fox P.F., McSweeney P.L.H., Cogan T.M., Guinee T.P. (eds): Cheese - Chemistry, Physics and Microbiology. 3rd Ed. London, Academic Press: 391-396. Go to original source...
  18. Valero E., Villamiel M., Miralles B., Sanz J., Martínez-Castro I. (2001): Changes in flavour and volatile components during storage of whole and skimmed UHT milk. Food Chemistry, 72: 51-58. Go to original source...
  19. von Neubeck M., Baur C., Krewinkel M., Stoeckel M., Kranz B., Stressler T., Fischer L., Hinrichs J., Scherer S., Wenning M. (2015): Biodiversity of refrigerated raw milk microbiota and their enzymatic spoilage potential. International Journal of Food Microbiology, 211: 57-65. Go to original source... Go to PubMed...
  20. Vyletělová M., Benda P., Hanuš O., Kopunecz P. (1999): Determination of total psychrotrophic microorganisms in bulk milk samples and their relationship to total count of microorganisms. Czech Journal of Food Sciences, 17: 216-222.

This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International (CC BY NC 4.0), which permits non-comercial use, distribution, and reproduction in any medium, provided the original publication is properly cited. No use, distribution or reproduction is permitted which does not comply with these terms.