Sunflower meal-based high moisture meat analogues: Impact of extrusion temperature and moisture on physical and nutritional properties

Incorporating food industry by-products, such as sunflower meal (SFM), into innovative food products can be a promising strategy to enhance the sustainability of food systems. This study investigated the production of high-moisture meat analogues (HMMAs) using extrusion cooking, using blends of pea protein isolate and expeller-pressed SFM. The influence of feed moisture content (FMC) (48% and 58%, wet basis), extruder barrel temperature profile (60-80-115-125°C, 80-100-125-135°C, and 100-120-135-145°C), and SFM concentration (40% and 50%) on the physical and nutritional properties of the resulting HMMAs were studied. The cooling die temperature was maintained at 80-50°C. A constant screw speed of 200 rpm and a dry feed rate of 0.5 kg/h (db) were used. Increasing FMC significantly (p < 0.05) reduced the specific mechanical energy needed for extrusion. Texture analysis, including cutting strength and texture profile analysis, showed that HMMAs became softer as FMC increased and extrusion temperature decreased. Additionally, extrusion reduced levels of antinutritional compounds, including phytates, trypsin inhibitors, and chlorogenic acid. In vitro protein digestibility of the HMMAs ranged from 86% to 89% and was not significantly (p < 0.05) affected by variations in FMC, extrusion temperature or SFM content. Despite the high in vitro protein digestibility of the HMMAs, all formulations were deficient in tryptophan for children aged 2–5 years, indicating that higher levels of pea protein would be required to create nutritionally complete meat alternatives. This research offers valuable insights into the potential of replacing pea protein with SFM to produce HMMAs, demonstrating a sustainable way to add value to an underutilized by-product in the food industry.