Lin Derong, Liu Yinhe, Ma Yi, Qin Wen, Zhang Qing
College of Food Science, Sichuan Agricultural University, Ya'an 625014, China.
College of Food Science, Sichuan Agricultural University, Ya'an 625014, China.
Int J Biol Macromol. 2024 Dec;283(Pt 1):137616. doi: 10.1016/j.ijbiomac.2024.137616. Epub 2024 Nov 14.
This study investigated the modification of highland barley bran through co-fermentation of Lactobacillus bulgaricus and Kluyveromyces marxianus, and developed a dynamic prediction model for DF content under these co-fermentation conditions using machine learning algorithms. The results showed that the XGBoost algorithm could predict changes in the DF component content (R = 0.9553(SDF/IDF), RMSE = 0.0464.) and identify optimal fermentation conditions. Under these optimal conditions, both strains exhibited synergistic effects, where the lactic acid produced by Lactobacillus bulgaricus and β-glucosidase produced by Kluyveromyces marxianus may facilitate IDF decomposition and conversion, resulting in a maximum SDF/IDF ratio of 0.6911. This led to a 27.65 % reduction in IDF content and a 19.11 % increase in SDF content. Moreover, the physicochemical and functional properties of DF were enhanced after co-fermentation. The structure of DF became looser and more porous, its thermal stability improved, and its water-holding, oil-holding, and swelling capacities increased by 53.54 %, 16.11 %, and 44.96 %, respectively, compared with the unfermented counterpart; in terms of adsorption characteristics, its glucose, cholesterol and nitrite adsorption capacities were also significantly improved. According to in vitro gastrointestinal simulated digestion, digestion would have a great impact on the fermented DF, which showed good antioxidant properties during the intestinal digestion stage.
本研究通过保加利亚乳杆菌和马克斯克鲁维酵母的共发酵研究了青稞麸皮的改性，并使用机器学习算法建立了这些共发酵条件下膳食纤维（DF）含量的动态预测模型。结果表明，XGBoost算法可以预测DF成分含量的变化（R = 0.9553（可溶性膳食纤维/不溶性膳食纤维），均方根误差 = 0.0464），并确定最佳发酵条件。在这些最佳条件下，两种菌株表现出协同作用，其中保加利亚乳杆菌产生的乳酸和马克斯克鲁维酵母产生的β-葡萄糖苷酶可能促进不溶性膳食纤维的分解和转化，导致最大可溶性膳食纤维/不溶性膳食纤维比率为0.6911。这使得不溶性膳食纤维含量降低了27.65%，可溶性膳食纤维含量增加了19.11%。此外，共发酵后DF的物理化学和功能特性得到增强。与未发酵的相比，DF的结构变得更松散、更多孔，其热稳定性提高，其持水、持油和膨胀能力分别提高了53.54%、16.11%和44.96%；在吸附特性方面，其葡萄糖、胆固醇和亚硝酸盐吸附能力也显著提高。根据体外胃肠道模拟消化，消化对发酵后的DF有很大影响，其在肠道消化阶段表现出良好的抗氧化性能。
