摘要
以燕麦粉为原料,分别利用植物乳杆菌(L.p)和旧金山乳杆菌(L.s)两种乳酸菌对其进行发酵,研究燕麦淀粉在发酵过程中各种物化及热力学特性的变化。结果表明:燕麦粉经过两种菌发酵后pH值下降,且L.p发酵的燕麦粉pH值下降的速率和产酸量都大于L.s。但是到发酵后期,两种乳酸菌发酵的燕麦粉pH值相近。发酵燕麦淀粉的溶解度和溶胀力都随着温度的升高而增加,在不同温度下,其溶胀力和溶解度在发酵过程中的变化趋势不同,经L.P发酵的样品的溶胀力低于L.s,但溶解度大于经L.s发酵的样品。快速黏度分析仪(RVA)和差示扫描量热仪(DSC)分析得到发酵过程中燕麦淀粉的变化:发酵后燕麦淀粉糊化过程中峰值黏度随着发酵时间的延长而降低,糊化起始温度提前,糊化所需时间延长,糊化焓升高,且L.s发酵样品的糊化焓值高于L.p。发酵后燕麦淀粉的直链淀粉含量在发酵过程中呈上升趋势,L.p发酵的样品的直链淀粉的含量高于L.s。
Oat flour was fermented solely with two species of lactic acid bacteria,Lactobacillus plantarum (L.p) and Lactobacillus sanfrancisco (L.s) in order to analyze the changes in physio-chemical and thermaldynamic properties of oat starch during lactic acid bacterial (LAB) fermentation. Fermentation with each of the two stains resulted in a decrease in pH,and L.p -fermented oat flour exhibited a faster pH drop and lager amount of acid production when compared to L.s-fermented one,but similar pH values were observed in the late period of fermentation. For both L.p-and L.s-fermented oat flours,solubility and swelling power increased with increasing temperature. For oat flour fermented by one strain,the two parameters at different temperatures both had different change trends as fermentation time increased. L.p-fermented oat flour had lower swelling power but higher solubility than its L.s-fermented counterpart. The results obtained from rapid viscosity analyzer (RVA) and differential scanning calorimetry (DSC) showed that the peak viscosity of fermented oat starch decreased as fermentation time increased,and after fermentation,oat starch had lower onset gelatinization temperature,required longer time for gelatinization,presented higher gelatinization enthalpy,and L.s-fermented oat starch had higher gelatinization enthalpy than L.p-fermented one. Oat starch presented an increasing trend in amylose content during fermentation,and L.p-fermented oat starch had higher amylose content at 6 and 12 hours of fermentation when compared to L.s-fermented one,but the amylose content of the former was slightly lower than that of the latter at 24 hours.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2010年第19期100-105,共6页
Food Science
基金
加拿大农业部国际交流与合作项目(CCSIC-Food-00107)
国家现代农业产业技术体系建设专项(nycytz-14)
关键词
乳酸菌
发酵
燕麦淀粉
糊化
直链淀粉
lactic acid bacteria
fermentation
oat starch
gelatinization
amylose content