Complex pectin metabolism by Lactobacillus and Streptococcus suggests an effective control approach for Maillard harmful products in brown fermented milk  

作　　者：Zibian Fan Wei Jia An Du Lin Shi 

机构地区：[1]School of Food and Biological Engineering,Shaanxi University of Science&Technology,Xi'an 710021,China [2]Shaanxi Research Institute of Agricultural Products Processing Technology,Xi'an 710021,China

出　　处：《Fundamental Research》2024年第5期1171-1184,共14页自然科学基础研究（英文版）

基　　金：supported by grants from the National Natural Science Foundation of China(32272401,31801643);Xianyang Science and Technology Plan Project(2021ZDYF-NY-0025);Xi'an Science and Technology Plan Project(21NYYF0056);Innovation Capability Support Program of Shaanxi(2021KJXX-37).

摘　　要：Harmful Maillard reaction products(HMRPs)derived from brown fermented milk pose a potential threat to human health,but the conversion mechanism during the manufacturing process remains elusive and urgently needs to be controlled.Acrylamide(FC 2.14,adjusted p-value=0.041),5-hydroxymethylfurfural(FC 2.61,adjusted p-value=0.026)and methylglyoxal(FC 2.07,adjusted p-value=0.019)were identified as the significantly increased HMRPs after browning in this study and the analysis of proteomics integrated with untargeted metabolomics demonstrated that the degradation of HMRPs was jointly accomplished by Streptococcus thermophilus and Lactobacillus bulgaricus.The galactose oligosaccharide metabolism in Streptococcus thermophilus was identified as a key biochemical reaction for HMRPs degradation,and the hydrolysates of pectin could be utilized as prebiotics for Streptococcus thermophilus.Eighteen classes of enzymes of L.bulgaricus and Streptococcus thermophilus related to energy metabolism were upregulated in the pectin-added group,indicating that the entry of acrylamide and methylglyoxal into the tricarboxylic acid cycle was accelerated.NAD-aldehyde dehydrogenase and alanine dehydrogenase are enzymes belonging to Streptococcus thermophilus,and their downregulation accelerated the efflux of acetate,which was beneficial for the proliferation of L.bulgaricus and prevented the conversion of pyruvate to l-alanine,thus facilitating the energy metabolism.The recoveries and relative standard deviations of the intraday and interday precision experiments were 89.1%-112.5%,1.3%-8.4%and 2.1%-9.4%,respectively,indicating that the developed approach was credible.Sensory evaluation results revealed that the brown fermented milk added with pectin had a better flavor,which was due to the fact that the supplement of polysaccharide promoted the fatty acid metabolism of lactic acid bacteria and increased the aroma substances including octoic acid and valeric acid.This study provided an insight into the formation and degradation mechanism of HMR

关 键 词：Brown fermented milk Harmful Maillard reaction products Metabolomics Proteomics Risk substance regulation 

分 类 号：O62[理学—有机化学]