NutriCubes: Nutritional and Sensory Quality of Fermented Cereal-Legume Snacks

NutriCubes is a novel baked, cube-shaped snack formulated from oat-legume flour blends (70:30) incorporating lactic-fermented lentil (O-L), chickpea (O-C), or pea (O-P) flours, developed to bridge the gap between nutritional quality and convenience in the plant-based snack market. Fermentation with a mixed lactic acid bacteria (LAB) starter (Lactiplantibacillus plantarum, Lacticaseibacillus casei, and Lactobacillus delbrueckii subsp. bulgaricus; 108 CFU/g; 30 °C; 24 h) reduced phytate by 53.3%, 45.3%, and 26.5% and tannins by 38.5%, 45.8%, and 37.5% in lentil, chickpea, and pea flours, respectively. All three NutriCubes formulations delivered 19.12–19.66 g protein/100 g fresh weight (FW) and 10.72–12.60 g dietary fibre/100 g FW. Cereal–legume complementarity was reflected in a favourable amino acid balance, with estimated Protein Efficiency Ratios ranging from 1.510 (O-C) to 1.989 (O-L). O-L showed the highest total polyphenol content (6.28 ± 0.13 mg GAE/g dry matter (DM)) and antioxidant activity (72.9 ± 1.22% DPPH inhibition). Hedonic panel evaluation (n = 107) confirmed strong acceptance across all formulations (7.48–8.12/9), with O-L scoring highest for taste (8.36 ± 0.70), colour (8.76 ± 0.44), and overall liking. The oat–lentil formulation emerged as the most nutritionally dense and sensorially preferred variant, establishing NutriCubes as a feasible snack with functional potential as an alternative.