Effect of Combined Treatment of Heat Moisture and Ultrafine Grinding on the Quality of Gluten-Free Brown Rice Biscuits

Brown rice is a nutritious, gluten-free whole grain, the edible potential of which is limited by inferior palatability and storage stability. In this study, brown rice (20% <i>w</i>/<i>w</i>) was subjected to heat moisture treatment (HMT) at 110 °C for 2 h, followed by ultrafine grinding, to prepare gluten-free biscuits, which were compared with those made from wheat flour, white rice, and brown rice. The results showed that the content of dietary fiber (2.67-3.62%), total phenolic (0.053-0.154%), and vitamin E (0.574-1.483 mg/100 g) in brown rice biscuits after combined treatment was enhanced compared with wheat flour biscuits. The spread ratio (4.06-8.89), hardness (700.82-1085.91 g), and brittleness (1068.89-2067.18 g/sec) of the biscuits were significantly improved (<i>p</i> < 0.05). Scanning electron microscopy revealed that the biscuits treated with combined treatment had fewer cavities and a more compact texture. The biscuits made from HMT brown rice demonstrated a reduced peroxide value, with a slower increase in acid value (0.19-0.21 mg/g) compared to untreated samples (0.24-0.38 mg/g) during storage. The innovative combined treatment of HMT and ultrafine grinding improved qualities of brown rice biscuits. This approach expands the utilization potential of brown rice, while also offering a viable strategy for grain conservation and loss reduction.