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

TL;DR

A new method combining heat moisture treatment and ultrafine grinding improves the quality and storage stability of gluten-free brown rice biscuits.

Contribution

A novel combined treatment enhances brown rice biscuit quality and storage stability, expanding its utilization potential.

Findings

Combined treatment increased dietary fiber, phenolic, and vitamin E content in brown rice biscuits.

Biscuit spread ratio, hardness, and brittleness improved significantly with the new treatment.

Treated biscuits showed reduced peroxide and acid values during storage, indicating better stability.

Abstract

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% w/w) 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 (p < 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.

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