Physicochemical composition, microbiological quality and consumers’ acceptability of raw and pasteurized locally produced goat milk


  • Zarinah binti Zakaria Universiti Sultan Zainal Abidin
  • Wong Shi Yun Universiti Sultan Zainal Abidin
  • Nadiawati Alias Universiti Sultan Zainal Abidin
  • Siti Nuriah Mohd Noor Universiti Sultan Zainal Abidin
  • Abd Jamil Zakaria Universiti Sultan Zainal Abidin
  • Zakiah Mustapha Universiti Sultan Zainal Abidin
  • Napisah Hussin Universiti Sultan Zainal Abidin
  • Wan Rohani Wan Taib Universiti Sultan Zainal Abidin
  • Aryati Ahmad Universiti Sultan Zainal Abidin
  • Noor Aini Mohd Yusoff Universiti Sultan Zainal Abidin



Pasteurized goat milk, physicochemical composition, microbiological qualities, lactic acid bacteria, sensory evaluation


The present study aimed to compare the raw and pasteurized goat milks in aspects of physicochemical composition, microbiological quality, and stability of lactic acid bacteria. Consumers’ acceptability to locally produced goat milk was also determined. Raw and pasteurized (LTLT) Saanen goat milks were analyzed while commercial (HTST and homogenized) goat milk was used as control. While pasteurization (LTLT) showed no significant effect on fat, protein, lactose, and ash content of raw goat milk (p>0.05). LTLT pasteurization kept the physicochemical properties of goat milk such as pH and viscosity similar to raw goat milk (p>0.05), there was a significant difference of titratable acidity (p<0.05). After LTLT and HTST pasteurizations, goat milk showed an increase in lightness with a reduction in yellowness, as well as significant reduction in microbial load. Survivability of lactic acid bacteria (anaerobic) was not affected by both pasteurization process (p>0.05). All of the studied goat milks contain lactic acid bacteria, primarily Enterococcus sp. via molecular identification by using 16S rRNA primer. Thus, LTLT pasteurization process at 63°C, 30 minutes might be applied to develop fermented dairy products such as probiotic goat drinks. According to sensory evaluation, consumer showed acceptability to locally produced goat milk with preference to commercial goat milk samples. In conclusion, lactation stage of goats and thermal processing conditions applied need to be considered since it might affect the quality of goat milk produced. To sum, the current information of locally produced goat milk would be useful for the development and manufacture of goat milk products especially in local dairy industry.


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