Research Group for Microbial Biotechnology and Biorefining, National Food Institute, Technical University of Denmark, Building 202, 2800 Kongens Lyngby, Denmark.
Combinatorial Microbiology, Novonesis, Gl. Venlighedsvej 14, 2970 Hørsholm, Denmark.
Food Res Int. 2024 Dec;197(Pt 1):115200. doi: 10.1016/j.foodres.2024.115200. Epub 2024 Oct 28.
The antinutrients and off-flavors present in plant-based foods are some of the major organoleptic and consumer acceptance drawbacks considered when developing plant-based fermented dairy alternatives (PBFDA). Here, we investigated a combination of genotypical and phenotypical consecutive screening methods to find out the optimal single- and combination of lactic acid bacteria (LAB) strains based on volatile off-flavors, phenolic acids, saponins, and trypsin inhibitor degradation through the fermentation of a pea, oat, and potato (POP) blend. Lactiplantibacillus plantarum strains were the most optimal for the partial/complete degradation of p-coumaric (>98 %) and ferulic acid (10-20 %) compounds in the POP blend. Leuconostoc pseudomesenteroides strains, and their PII-type proteinases were demonstrated to be effective degrading trypsin inhibitors. Also, specific Leuconostoc mesenteroides and L. plantarum strains achieved higher degradation rates of plant saponins such as avenacoside A (10-40 % degradation) and soyasaponin B (55-75 % degradation) present, correlated with their β-glucosidase activity (30-50 U/mL). Strict heterofermentative LABs such as Leuconostoc spp. strains were significantly better at removing hexanal, pentanal, benzaldehyde, and nonanal up to 85 % after 6 h. Finally, 384 combinations of 2 and 3 LAB selected strains (L. plantarum - L. mesenteroides - L. pseudomesenteroides) were tested at different strain-ratios, which demonstrated synergistic effects at degrading ferulic acid to more than 80 %, increasing acidification rates, and producing higher concentrations of diacetyl and acetoin (up to 3.28 and 28.13 µg/g sample) when L. pseudomesenteroides 1993 was included in the mix. This study demonstrated the potential of using unconventional plant-adapted LAB strains as starter cultures for the elimination of multiple unwanted compounds for the development of higher quality PBFDA without the use of conventional dairy-based LAB isolates. Finally, the screening approach could be used for microbial screening purposes throughout the development of starter cultures for plant-based yogurts, cheese, and other non-dairy fermented products.
植物性食物中存在的抗营养因子和异味是开发植物性发酵乳制品替代品（PBFDA）时需要考虑的主要感官和消费者接受度方面的缺陷。在这里，我们研究了组合使用基因型和表型连续筛选方法，以找到基于挥发性异味、酚酸、皂苷和胰蛋白酶抑制剂降解的最佳单一和组合乳酸菌（LAB）菌株，通过豌豆、燕麦和土豆（POP）混合物的发酵。植物乳杆菌菌株最适合部分/完全降解 POP 混合物中的对香豆酸（>98%）和阿魏酸（10-20%）化合物。证明 Leuconostoc pseudomesenteroides 菌株及其 PII 型蛋白酶能够有效降解胰蛋白酶抑制剂。此外，特定的肠膜明串珠菌和植物乳杆菌菌株实现了更高的植物皂苷降解率，如阿魏酰蔗糖 A（10-40%降解）和大豆皂苷 B（55-75%降解），与它们的β-葡萄糖苷酶活性（30-50 U/mL）相关。严格的异型发酵乳酸菌（如肠膜明串珠菌）在 6 小时后能够显著去除 85%的己醛、戊醛、苯甲醛和壬醛。最后，测试了 2 种和 3 种 LAB 选定菌株（植物乳杆菌-肠膜明串珠菌-肠膜明串珠菌）的 384 种组合在不同菌株比例下的效果，当包含肠膜明串珠菌 1993 时，这些组合在降解阿魏酸方面表现出协同作用，超过 80%，提高酸化速率，并产生更高浓度的二乙酰和乙酰基（高达 3.28 和 28.13 µg/g 样品）。本研究表明，使用非传统的植物适应性 LAB 菌株作为起始培养物具有潜力，可以消除多种不需要的化合物，开发出更高质量的 PBFDA，而无需使用传统的基于乳制品的 LAB 分离物。最后，该筛选方法可用于植物性酸奶、奶酪和其他非乳制品发酵产品起始培养物开发过程中的微生物筛选。
