Development of fibre- and vitamin-enriched corn extrudates utilising wheat and rice bran under varying extrusion conditions

Abstract

In the current study, the impacts of bran type (BT), extrusion process (EP), exit die temperature (EDT), and bran supplementation level (BSL) on the physical, functional, and nutritional attributes of corn extrudates supplemented with wheat bran (WB) or rice bran (RB) were systematically investigated. Extrudates were produced at 80 or 130 °C EDT with/without CO2 injection EP using 5%, 10%, or 15% BSL. Total dietary fibre, vitamin B contents (thiamine, riboflavin, niacin), extrudate density, and breaking strength increased significantly (p < 0.05) with higher WB and RB levels. Conversely, the radial expansion index and water binding capacity decreased significantly (p < 0.05). All studied quality characteristics of extrudates were significantly affected by BSL (p < 0.001). Overall, corn extrudates supplemented with WB showed considerably higher total dietary fibre contents compared to RB counterparts. However, samples produced with RB consistently had significantly higher vitamin B levels under all extrusion conditions. Practical Applications: It is well known that snack foods sold in markets tend to have higher fat levels and lower dietary fibre. Recently, there has been increasing attention towards healthy snacks. The current study clearly demonstrates that both wheat bran and rice bran can be practically utilised to produce fibre- and vitamin-rich extrudates, thereby facilitating the development of healthier food products.