Studies of the Microbiological and Physico-Chemical Composition of Goat´s Milk from North-Western Spain

  • Juliana Ramos-Pereira
  • Edson A. Rios
  • Jose M. Rodríguez-Calleja
  • Jesús A. Santos
  • Teresa M. López-Díaz
Keywords: goat´s milk, micobiological counts, lactic adid bacteria, physical and chemical composition


Twenty-seven samples of raw goat’s milk were collected from four farms in the North-West of Spain with the aim of analysing counts of various mesophilic bacteria and of determining the physical and chemical composition during different seasons of the year. Overall mean values for mesophilic aerobic micro-organisms (Standard Plate Counts, SPCs) were above 5.6 log cfu/ml, very similar to the counts on M17 agar (presumptive Lactococcus, 5.6 log cfu/ml) and higher than the counts on MSE agar (presumptive Leuconostoc, 4.6 log cfu/ml) and on MRS agar (presumptive Lactobacillus, 4.4 log cfu/ml). Counts were generally higher in winter than in spring and summer, although no statistically significant differences were found. The microbiological quality of raw goat’s milk produced in the farms investigated in the North-West of Spain is only partially in accordance with European Union standards. Hence, hygiene practices should be improved so as to decrease the standard plate counts on some of the farms checked. The physical and chemical composition tests also showed higher values for fat, protein and dry extract during the winter season. The average fat content (5.5 g/100 ml) and dry extract (14.7 g/100 ml) were higher than the values noted in other studies, making this of interest for cheese making.


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