[关键词]
[摘要]
对新疆自然发酵骆驼乳中乳酸菌菌群进行分离鉴定得到五株乳酸菌,其中乳杆菌3株分别为瑞士乳杆菌(Lactobacillus helveticus)、植物乳杆菌(Lactobacillus plantrum)和开菲尔乳杆菌(Lactobacillus kefiri),片球菌2株分别为乳酸片球菌(Pediococcus acidilactici)戊糖片球菌(Pediococcus pentosaceus)。分离鉴定出的五株乳酸菌在培养基中生长良好,其活菌数在培养16 h后能达到109 CFU/mL。将传统酸奶发酵剂接种于骆驼乳中并于42 ℃条件下培养,发现其在骆驼乳中能较好地产酸,其添加量在0.1%时最适。将筛选到的乳酸菌制备成生产发酵剂与传统酸奶发酵剂复配,得到瑞士乳杆菌组的复配效果最佳,具有最优的产酸效果,在经过6 h发酵后pH值降到4.5左右,酸度达到85 oT,且制备的发酵骆驼乳具有最好的感官品质,其感官评分明显高于其他菌株复配进行发酵的骆驼乳产品。因此,可将0.1%传统酸奶发酵剂与筛选到的瑞士乳杆菌制备的生产发酵剂复配应用于酸驼乳发酵。
[Key word]
[Abstract]
Five strains of lactic acid bacteria (LAB) were isolated and identified in Xinjiang naturally fermented camel milk, including three strains of lactobacilli (Lactobacillus helveticus, Lactobacillus plantrum, and Lactobacillus kefiri) and two strains of Pediococcus acidilactici (Pediococcus acidilactici and Pediococcus pentosaceus). These LAB strains showed good growth in the culture medium, where the viable cell count reached 109 colony-forming units (CFU)/mL after 16 h of cultivation. Traditional yogurt starter culture was inoculated in camel milk and incubated at 42 ℃ and the results showed effective acid production, where optimum acid production was achieved with 0.1% traditional yogurt starter culture. The isolated LAB strains were prepared as fermenting agents combined with traditional yogurt starter culture. The combination using Lactobacillus helveticus exhibited optimal synergistic effect and acid-generating efficiency. After six hours of fermentation, the pH value reached approximately 4.5, with acidity value of 85 oT. Furthermore, the fermented camel milk showed higher sensory quality and a higher sensory evaluation score compared with fermented camel milk samples prepared using combinations of other strains. Therefore, the fermenting agent combination of 0.1% traditional yogurt starter with Lactobacillus helveticus strains can be used for acid camel milk fermentation.
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[基金项目]
乳业生物技术国家重点实验室开放课题(SKLDB2015-001);国家自然科学基金(3147172)