Comparison on the Physicochemical Characteristics of Skim Milk Fermented by Akkermansia muciniphila at Different Concentrations in Formulated Milk

YE Genyun; WU Zhongqin; XU Lu; JIANG Jiayan; YUAN Binfeng; LI Zongjun

doi:10.13982/j.mfst.1673-9078.2025.2.0097

Abstract：Akkermansia muciniphila(Akk)has garnered widespread attention as a potential novel probiotic.In this study,skim milk was formulated with Akk nutrient medium in certain proportions to prepare formulated skim milk at different concentrations,and then the formulated skim milk was inoculated with Akk for fermentation.The nutritional characteristics of Akk-fermented milk were evaluated by measuring the pH,stability,soluble protein content,protease activity,free amino acids,short-chain fatty acid content,as well as 2,2-Diphenyl-l-picrylhydrazyl(DPPH·)scavenging capacity,hydroxyl radical scavenging capacity,and 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate)(ABTS+·)scavenging capacity.The results showed that the main short-chain fatty acid produced in Akk-fermented skim milk was acetic acid,and with the increase of BHI content in the fermentation broth,the pH value and soluble protein content of the fermentation broth showed a significant downward trend,decreasing to 5.21 and 4.9 mg/mL,respectively.The protease activity continuously increased,reaching a maximum of 51.02 U/mL.A total of seventeen free amino acids were detected,with leucine having the highest content(305.517 8 μg/mL)and cysteine having the lowest content;Glutamic acid decreased significantly(from 62.495 5 μg/mL to 5.818 9 μg/mL);The DPPH radical scavenging capacity and reducing power continuously increased,whilst the hydroxyl radical scavenging capacity decreased.In summary,in the presence of growth factors,Akk can be used for milk fermentation.In the future,after further verification of the safety of animal-derived growth factors,elimination of the influence of scientific and technological ethics,or the discovery of new non-animal-derived growth factors for Akk,a new generation of Akk-fermented functional milk is expected to be introduced.