Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-26T22:55:11.680Z Has data issue: false hasContentIssue false

Microbiological quality of milk from farms to milk powder manufacture: an industrial case study

Published online by Cambridge University Press:  03 June 2019

Lizandra F. Paludetti
Affiliation:
Teagasc Moorepark, Animal & Grassland Research and Innovation Centre, Fermoy, County Cork, Ireland School of Food and Nutritional Sciences, University College Cork, County Cork, Ireland
Alan L. Kelly
Affiliation:
School of Food and Nutritional Sciences, University College Cork, County Cork, Ireland
Bernadette O'Brien
Affiliation:
Teagasc Moorepark, Animal & Grassland Research and Innovation Centre, Fermoy, County Cork, Ireland
Kieran Jordan
Affiliation:
Teagasc Moorepark, Food Research Centre, Fermoy, County Cork, Ireland
David Gleeson*
Affiliation:
Teagasc Moorepark, Animal & Grassland Research and Innovation Centre, Fermoy, County Cork, Ireland
*
Author for correspondence: David Gleeson, Email: David.Gleeson@teagasc.ie

Abstract

The experiments reported in this research paper aimed to track the microbiological load of milk throughout a low-heat skim milk powder (SMP) manufacturing process, from farm bulk tanks to final powder, during mid- and late-lactation (spring and winter, respectively). In the milk powder processing plant studied, low-heat SMP was produced using only the milk supplied by the farms involved in this study. Samples of milk were collected from farm bulk tanks (mid-lactation: 67 farms; late-lactation: 150 farms), collection tankers (CTs), whole milk silo (WMS), skim milk silo (SMS), cream silo (CS) and final SMP. During mid-lactation, the raw milk produced on-farm and transported by the CTs had better microbiological quality than the late-lactation raw milk (e.g., total bacterial count (TBC): 3.60 ± 0.55 and 4.37 ± 0.62 log 10 cfu/ml, respectively). After pasteurisation, reductions in TBC, psychrotrophic (PBC) and proteolytic (PROT) bacterial counts were of lower magnitude in late-lactation than in mid-lactation milk, while thermoduric (LPC—laboratory pasteurisation count) and thermophilic (THERM) bacterial counts were not reduced in both periods. The microbiological quality of the SMP produced was better when using mid-lactation than late-lactation milk (e.g., TBC: 2.36 ± 0.09 and 3.55 ± 0.13 cfu/g, respectively), as mid-lactation raw milk had better quality than late-lactation milk. The bacterial counts of some CTs and of the WMS samples were higher than the upper confidence limit predicted using the bacterial counts measured in the farm milk samples, indicating that the transport conditions or cleaning protocols could have influenced the microbiological load. Therefore, during the different production seasons, appropriate cow management and hygiene practices (on-farm and within the factory) are necessary to control the numbers of different bacterial groups in milk, as those can influence the effectiveness of thermal treatments and consequently affect final product quality.

Type
Research Article
Copyright
Copyright © Hannah Dairy Research Foundation 2019 

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

Barbano, DM, Ma, Y and Santos, MV (2006) Influence of raw milk quality on fluid milk shelf-life. Journal of Dairy Science 89, E15E19.Google Scholar
Burgess, SA, Lindsay, D and Flint, SH (2010) Thermophilic bacilli and their importance in dairy processing. International Journal of Food Microbiology 144, 215225.Google Scholar
Celestino, EL, Iyer, M and Roginski, H (1997) The effects of refrigerated storage of raw milk on the quality of whole milk powder stored for different periods. International Dairy Journal 7, 119127.Google Scholar
Cherif-Antar, A, Moussa-Boudjemaa, B, Didouh, N, Medjahdi, K, Mayo, B and Florez, AB (2016) Diversity and biofilm-forming capability of bacteria recovered from stainless steel pipes of a milk-processing dairy plant. Dairy Science and Technology 96, 2738.Google Scholar
Craven, HM, McAuley, CM, Duffy, LL and Fegan, N (2010) Distribution, prevalence and persistence of Cronobacter (enterobacter sakazakii) in the nonprocessing and processing environments of five milk powder factories. Journal of Applied Microbiology 109, 10441052.Google Scholar
Delgado, S, Rachid, CTCC, Fernandez, E, Rychlik, T, Alegria, A, Peixoto, RS and Mayo, B (2013) Diversity of thermophilic bacteria in raw, pasteurized and selectively-cultured milk, as assessed by culturing, PCR-DGGE and pyrosequencing. Food Microbiology 36, 103111.Google Scholar
EU Regulation 853/2004 (2004) Regulation (EC) No 853/2004 of the European Parliament and of the Council of 29 April 2004 Laying down specific hygiene rules for food of animal origin. Official Journal of the European Union L226 2282Google Scholar
Frank, JF and Yousef, AE (2004) Test for groups of microorganisms. In Wehr, HM and Frank, JF (eds), Standard Methods for the Examination of Dairy Products, 17th Edn, Washington, DC: American Public Health Association, pp. 227248.Google Scholar
Graham, T (2004) Sampling dairy and related products. In Wehr, HM and Frank, JF (eds), Standard Methods for the Examination of Dairy Products, 17th Edn, Washington, DC: American Public Health Association, pp. 6391.Google Scholar
Huck, JR, Sonnen, M and Boor, KJ (2008) Tracking heat-resistant, cold-thriving fluid milk spoilage bacteria from farm to packaged product. Journal of Dairy Science 91, 12181228.Google Scholar
Jindal, S, Anand, S, Huang, K, Goddard, J, Metzger, L and Amamcharla, J (2016) Evaluation of modified stainless steel surfaces targeted to reduce biofilm formation by common milk sporeformers. Journal of Dairy Science 99, 95029513.Google Scholar
Kable, ME, Srisengfa, Y, Laird, M, Zaragoza, J, McLeod, J, Heidenreich, J and Marco, ML (2016) The core and seasonal microbiota of raw bovine milk in tanker trucks and the impact of transfer to a milk processing facility. MBio 4, 113.Google Scholar
Lafarge, V, Ogier, JC, Girard, V, Maladen, V, Leveau, JY, Gruss, A and Delacroix-Buchet, A (2004) Raw cow milk bacterial population shifts attributable to refrigeration. Applied and Environmental Microbiology 70, 56445650.Google Scholar
Laird, DT, Gambrel-Lenarz, SA, Scher, FM, Graham, TE and Reddy, R (2004) Microbiological count methods. In Wehr, HM and Frank, JF (eds), Standard Methods for the Examination of Dairy Products, 17th Edn, Washington, DC: American Public Health Association, pp. 153186.Google Scholar
Linn, JG (1988) Factors affecting the composition of milk from dairy cows. In National Research Council (US) Committee on Technological Options to Improve the Nutritional Attributes of Animal Products. Designing Foods: Animal Product Options in the Marketplace. Washington, DC: National Academy Press, pp. 224241.Google Scholar
Muir, D (1996) The shelf-life of dairy products: 1. Factors influencing raw milk and fresh products. International Journal of Dairy Technology 49, 2432.Google Scholar
Muir, DD, Griffiths, MW, Phillips, JD, Sweetsur, AWM and West, IG (1986) Effect of the bacterial quality of raw milk on the bacterial quality and some other properties of low-heat and high-heat dried milk. International Journal of Dairy Technology 39, 115118.Google Scholar
Murphy, SC, Martin, NH, Barbano, DM and Wiedmann, M (2016) Influence of raw milk quality on processed dairy products: how do raw milk quality test results relate to product quality and yield? Journal of Dairy Science 9, 1012810149.Google Scholar
O'Connell, A, McParland, S, Ruegg, PL, O'Brien, B and Gleeson, D (2015) Seasonal trends in milk quality in Ireland between 2007 and 2011. Journal of Dairy Science 98, 37783790.Google Scholar
Pinto, CLO, Martins, ML and Vanetti, MCD (2006) Microbial quality of raw refrigerated milk and isolation of psychrotrophic proteolytic bacteria. Food Science and Technology 26, 645651.Google Scholar
Quigley, L, O'Sullivan, O, Stanton, C, Beresford, TP, Ross, RP, Fitzgerald, GF and Cotter, PD (2013 a) The complex microbiota of raw milk. FEMS Microbiology Reviews 37, 664698.Google Scholar
Quigley, L, McCarthy, R, O'Sullivan, O, Beresford, TP, Fitzgerald, GF, Ross, RP, Stanton, C and Cotter, PD (2013 b) The microbial content of raw and pasteurized cow milk as determined by molecular approaches. Journal of Dairy Science 96, 49284937.Google Scholar
Ramsahoi, L, Gao, A, Fabri, M and Odumeru, JA (2011) Assessment of the application of an automated electronic milk analyser for the enumeration of total bacteria in raw goat milk. Journal of Dairy Science 94, 32793287.Google Scholar
SAS (2016) Version 9.3. SAS Institute Inc., Cary NC USA.Google Scholar
Teh, KH, Flint, S, Palmer, J, Lindsay, D, Andrewes, P and Bremer, P (2011) Thermo-resistant enzyme-producing bacteria isolated from the internal surfaces of raw milk tankers. International Dairy Journal 21, 742747.Google Scholar
Tucker, G (2015) Pasteurisation: principles and applications. In Caballero, B, Finglas, P and Toldra, F (eds), Encyclopedia of Food and Health, 1st Edn, Oxford, UK: Academic Press, pp. 264269.Google Scholar
Vyletelova, M, Hanus, O, Urbanova, E and Kopunecz, P (2000) The occurrence and identification of psychrotrophic bacteria with proteolytic and lipolytic activity in bulk milk samples at storage in primary production conditions. Czech Journal of Animal Science 45, 373383.Google Scholar
Watterson, MJ, Kent, DJ, Boor, KJ, Wiedmann, M and Martin, NH (2014) Evaluation of dairy powder products implicates thermophilic sporeformers as the primary organisms of interest. Journal of Dairy Science 97, 24872497.Google Scholar
Wehr, HM and Frank, JF (2004) Standard Methods for the Examination of Dairy Products, 17th Edn, Washington, DC: American Public Health Association.Google Scholar
Supplementary material: PDF

Paludetti et al. supplementary material

Paludetti et al. supplementary material 1

Download Paludetti et al. supplementary material(PDF)
PDF 405.9 KB