Fermentation for Designing Innovative Plant-Based Meat and Dairy Alternatives

**Background:** Plant-based meat and dairy alternatives are increasingly popular, but plant proteins often have lower nutritional quality, undesirable flavors, and different functional properties compared to animal proteins. Manufacturers frequently rely on additives (fats, starches, flavorings, stabilizers) or extensive processing to mimic animal products, resulting in ultra-processed foods (NOVA group 4) that may raise health concerns. Fermentation is emerging as a natural strategy to improve the quality of plant-based alternatives with minimal additives.

**Methods:** This is a narrative review synthesizing literature on the application of fermentation to plant-based dairy and meat alternatives. The authors searched Mintel GNPD for market data (4379 products retrieved, 2002–2022) and the GFI database for startup activity (151 startups using fermentation). The review covers three fermentation types: traditional (using bacteria/yeasts), biomass (producing single-cell proteins), and precision fermentation (using engineered microorganisms to produce specific compounds).

**Key Results:** The global fermented plant-based market was valued at USD 329.29 million in 2021 and is projected to reach USD 422.26 million by 2026 (CAGR 5.0%). Europe holds 73% market share. Dairy alternatives account for 26.3% of fermented plant-based products (yoghurt 9.6%, cheese 4.8%), and meat alternatives 8.6%. Fermentation with lactic acid bacteria (Lactobacillus spp., Bifidobacterium, Streptococcus thermophilus) improved protein digestibility, amino acid profiles, and bioactive peptide formation (ACE-inhibitory, antioxidative, antimicrobial). Fermentation reduced antinutrients: raffinose was reduced by 60% in fermented moringa leaves and beetroot extract. Allergen reduction was demonstrated—conglycinin (7S) and glycinin (11S) were drastically reduced in soymilk fermented by Enterococcus faecalis VB43. Off-flavors (n-hexanal, n-hexanol) were reduced by Bacillus subtilis, Lactobacillus species, and edible fungi. In yoghurt-like products, exopolysaccharide-producing Weissella confusa increased viscosity and water-holding capacity, achieving viable counts >10^9 CFU/mL. For cheese alternatives, fermentation with lactic bacteria and Geotrichum candidum improved sensory properties of soy-based cheese. Precision fermentation has enabled production of soy leghemoglobin (Impossible Foods) and Hemami™ heme protein for meat flavor, as well as beef fat alternatives and vitamin B12. Mycoprotein (Quorn™) from Fusarium venenatum has a PDCAAS of 0.99 and contains all essential amino acids.

**Clinical Implications:** Fermentation can produce plant-based alternatives with improved nutritional profiles (higher protein digestibility, better mineral bioavailability, reduced antinutrients) and reduced allergenicity, potentially offering healthier options compared to ultra-processed plant-based products. However, the digestibility of fermented plant-based products and their effects on gut microbiota are scarcely investigated. Consumer perception of precision fermentation remains a barrier, and more research is needed on the health impacts of these novel foods.