益生菌对发酵菠萝果汁综合品质的影响

菠萝果汁分别接种干酪乳杆菌、植物乳杆菌、嗜酸乳杆菌和肠膜明串珠菌进行发酵，研究菠萝果汁发酵过程中理化品质和感官品质的变化规律。结果表明，4种乳酸菌在菠萝果汁中生长良好，发酵24 h，植物乳杆菌和肠膜明串珠菌的活菌数对数值均已超过8.3；经乳酸菌发酵后，菠萝果汁的pH、维生素C（VC）含量均显著降低，而总酸、可溶性固形物、总酚、1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除率显著升高。其中，植物乳杆菌具有较强的产酸能力，肠膜明串珠菌能够延缓VC的流失。在对感官品质影响方面，4种发酵菠萝果汁之间存在差异，经肠膜明串株菌发酵的菠萝果汁感官评价较优（79.79分），而经嗜酸乳杆菌能够更好地保留菠萝果汁特有的挥发性香气成分。研究结果为益生菌菠萝果汁产品的开发提供参考依据和技术支持。

Effect of probiotics on the comprehensive quality of fermented pineapple juice

The pineapple juice was fermented by Lactobacillus casei,Lactobacillus plantarum,Lactobacillus acidophilus,and Leuconostoc mesenteroides,respectively.The change rules in physical and chemical quality and sensory quality of pineapple juice during the fermentation were studied.The results indicated that 4 lactic acid bacteria grew well in pineapple juice.After fermentation for 24 h,the viable counts of both L.plantarum and L.mesenteroides was>8.3 lg(cfu/ml).After lactic acid bacteria fermentation,the pH and vitamin C(VC)content of pineapple juice were significantly decreased,while the total acid,soluble solid,total phenol concentration and 1,1-diphenyl-2-picrylhydrazyl radical(DPPH)free radical scavenging rate were all dramatically increased.Among these 4 lactic acid bacteria,L.plantarum exhibited a higher capacity of producing acid,and L.mesenteroides could delay the loss of VC content.Furthermore,there were differences in the sensory quality of the 4 fermented pineapple juices.The pineapple juice fermented by L.mesenteroides obtained a higher score(79.79)in sensory evaluation,while L.acidophilus showed a better capacity of retaining the unique volatile aroma components of pineapple juice.The research results provided reference basis and technical support for the development of probiotic pineapple juice products.