低聚半乳糖对植物乳杆菌NMGL2发酵乳加工特性的影响

Effects of Galactooligosaccharides on Processing Characteristics of Lactobacillus Plantarum NMGL2 Fermented Milk

将不同添加量的低聚半乳糖(GOS)与植物乳杆菌(Lactobacillus plantarum)NMGL2混合培养,考察GOS对菌株NMGL2生长的影响,并将不同添加量的GOS(0、2%、4%、6%)应用于菌株NMGL2发酵乳中,研究其对发酵乳加工特性的影响。结果表明,GOS能促进菌株NMGL2的生长,并以4%(m/v)添加量的效果最佳;菌株NMGL2发酵乳加工过程中,GOS的添加促进了发酵前期菌株产酸速率,提升了发酵后期发酵乳弹性和黏性,但降低了其流动性;在发酵乳冷藏过程中,GOS延迟了发酵乳的后酸化速率,降低了冷藏期内活菌数下降速率,提高了发酵乳的持水力、硬度和体系稳定性。因此,GOS能够有效改善发酵乳加工特性,研究结果为功能性发酵乳的研发提供技术依据。

Different concentrations(0, 2%, 4%, 6%) of GOS were mixed with Lactobacillus plantarum NMGL2 to investigate the effect of GOS on the growth of strain NMGL2. GOS was applied to the Lactobacillus plantarum NMGL2 fermented milk, and its influence on the processing characteristics of fermented milk was studied. The results showed that GOS could promote the growth of the strain NMGL2, and the effect was the best with the addition of 4%(m/v). The addition of GOS promoted the acid production rate of the strain in the early stage of fermentation and decreased the fluidity index(FI), but increased the elasticity index(EI) and macroscopic viscosity index(MVI) of the fermented milk during the late fermentation period. During the refrigeration process of fermented milk, GOS retarded post-acidification rate of fermented milk, but reduced the rate of decline of viable bacteria during the refrigeration period and increased the water holding capacity and hardness of fermented milk, and improved the stability of the fermented milk. Therefore, GOS can effectively improve the processing characteristics of fermented milk and the results provide a technical basis for the development of functional fermented milk.