Abstract
This study characterized biochemical changes during pea seed (Pisum sativum L. cv. Aksary) germination, quantified thermolabile nutrient retention (vitamin C, thiamine, lysine) during infrared (IR) drying relative to grain temperature, optimized drying time and roller gap for maximal flake yield, and assessed physicochemical, nutritional, and microbiological quality of final flakes. Seeds were germinated (18–22 °C, 36–42 h, radicle 3–5 mm), IR dried (0.8–3.0 µm; heat flux 6.7 kW/m²; 0–180 s), and roll flaked (gap 0.3–0.8 mm) using the response surface methodology (central composite design); AOAC/ISO methods were used for nutrient analyses. Germination reduced trypsin inhibitor activity by 48% and phytic acid from 1.20 to 0.65 g/100 g dry weight, while vitamin C rose 3.9-fold and folic acid increased 47%. Nutrient losses accelerated sharply between 90 and 120 s once core temperature exceeded 70 °C. At the optimal condition (90 s; 0.6 mm roller gap), thiamine, vitamin C, and lysine retention reached 96.9%, 81.3%, and 96.8%, with 91% flake yield. This is the first study linking IR drying time, grain temperature, and nutrient retention in germinated peas, offering a science-based industrial protocol. The novelty of this study lies in defining kinetic degradation thresholds and a validated operating window for high bioactive retention with superior flake integrity.