A gastronomic exploration of protein digestibility, antioxidant activity, and bioavailability of selenium-enriched germinated brown rice under various cooking methods
Muhammad Tayyab Rashid, Kunlun Liu, Mengru Ning, Mushtaque Ahmed Jatoi, Nazish Muzaffar, Hazrat Usman
Abstract
The study investigates the effects of various cooking methods (normal pressure, microwave, and high pressure) on antioxidant activities, amino acid profiles, protein digestibility, and selenium bioavailability in germinated brown rice (GBR) and selenium-enriched brown rice (Se-GBR). Se-GBR showed higher antioxidant activity, including ABTS •+ scavenging and iron chelating ability, across all cooking methods. High-pressure cooking preserved these antioxidant properties, but reduced the reducing power of non-selenium-rich proteins, while microwave and normal pressure cooking increased it in Se-GBR. Cooking reduced ABTS •+ scavenging by 7.22 % in GBR samples compared to uncooked samples. In contrast, Se-GBR samples maintained higher scavenging rates of 65 % and 75 %, demonstrating their resilience to cooking-induced changes. Se-GBR samples had poorer gastrointestinal digestion than gastric digestion. Brown rice's reducing capacity and protein digestion products were unaffected by cooking. Additionally, trypsin digestion enhanced the ability to reduce digestive products compared to gastrointestinal digestion. Overall, gastric digestion exhibited greater reducing capacity while gastrointestinal digestion, was more effective at neutralizing free hydroxyl radicals. These findings emphasise the stability and functionality of selenium-enriched brown rice, highlighting its potential as a functional food to address dietary selenium deficiencies and promote public health. • Amino acid, protein, and selenium content was unaffected by cooking methods. • High-pressure and microwave cooking reduced protein and selenium bioavailability. • Cooking's impact on ABTS + and iron chelation varied with selenium-rich rice. • Cooking did not affect brown rice reduction ability or its protein digestion. • Trypsin digestion boost reduction ability of products compared to gastrointestinal.