Wh. Heeschen, MILK HYGIENE AND MILK SAFETY IN THE EUROPEAN AND INTERNATIONAL MARKETS, Kieler Milchwirtschaftliche Forschungsberichte, 50(1), 1998, pp. 53-77
The milk quality is determined by aspects of composition and hygiene.
The qualitative/hygienic requirements to be met by raw milk vary betwe
en categorical postulates for protecting human health and desirable pr
operties which are, from the nutritional point of view, conducive for
optimal consumption. The main criteria for raw milk of high qualitativ
e/hygienic value are: Low number of saprophytic microorganisms, Absenc
e or very low number of pathogenic microorganisms including mastitis p
athogens and Avoidance - as far as possible - of residues and contamin
ants and/or keeping them below maximum residue limits (MRLs). The sapr
ophytic bacteria (spoilage agents) in milk are subdivided according to
their main points of attack on the major milk constituents in the fol
lowing groups: Glycolytes (e.g. streptococci and lactobacilli), Proteo
lytes (e.g. pseudomonads, enterobacteriaceae, aerobic sporeformers) an
d Lipolytes (e.g. pseudomonads, micrococci, aeromonads, corynebacteria
). Presence and multiplication of saprophytic bacteria in raw milk mig
ht change the milk composition and influence the quality of the produc
ts. Moreover, the flavour of the raw milk may be adversely influenced
and heat-stable bacterial enzymes may continue to act in the product,
particular during long storage and adversely affect stability and/or f
lavour of cream and UHT milk. The pathogenic bacteria include ''classi
cal'' microorganisms and ''emerging pathogens''. At present, Salmonell
a, pathogenic Escherichia coli strains, Listeria monocytogenes, Campyl
obacter jejuni, Yersinia enterocolitica, Staphyloccous aureus are the
most important ones. The number of somatic cells is an indicator of th
e udder health and of the hygienic quality of the milk. The threshold
figure for herd bulk milk should be below 400,000/ml. In close relatio
n to the mastitis situation the occurrence of inhibitors (antibiotics,
sulfa drugs etc.) has to be seen. Inhibitors have significance from t
he technological and the public health points of view. Maximum residue
limits (MRLs) are developed by Coder Alimentarius and many countries
worldwide. The legal requirement for the quality of raw milk and the p
ayment systems are described on the basis of the Milk Hygiene Directiv
e 92/46 EEC and the results of IDF Questionnaire 2893/A (Group of Expe
rts A8). The information concerning milk payment systems for ex-farm m
ilk in the Bulletin of the International Dairy Federation Nr. 305/1995
gives the factual situation in the different IDF countries for the pe
riod 1992/93. The report highlights the disparate nature of the paymen
t systems and tackles the subject through surveying payments related t
o milk quality, hygienic quality, methodology of milk sampling and col
lection, and the various payment formulas. Some countries presented th
e data as was applicable during 1992 and others, which responded later
, presented the situation as it was in 1993 and 1994. Legal requiremen
ts in food hygiene include more and more the HACCP system. Moreover, r
isk analysis should be the scientific basis for all relevant decisions
related to hygiene and quality.