Selective peroxidase inactivation of lightly milled rice by superheated steam

Improvement in nutritional attributes of rice using superheated steam processing

“…High heat penetration and an oxygen-free environment are the major advantages of SS, which lead to rapid heating and reduced oxidative degradation reactions during processing (Anto, Bv, Gc, & Hebbar, 2014). In our previous study, we showed that the desirable physical and sensory properties of LMR were well preserved when the SS processing conditions were optimized: restricted moisture content (~14%), relatively low temperature (120°C) and short treatment time (2.5 min) (Wu et al, 2014). In the current study, we investigated the influence of SS processing on the chemical composition and nutritional attributes of LMR.…”

“…These bioactive phytochemicals have been shown to provide desirable health benefits beyond basic nutrition by reducing the risk of chronic diseases (Rebello, Greenway, & Finley, 2014). However, brown rice with an intact bran layer is rarely consumed owing to its inferior cooking quality and short shelf life (Wu et al, 2014). Our previous study (Wu et al, 2016) demonstrated that the inner aleurone layer of rice bran only had a marginal influence on rice cooking quality, and theoutermost cuticular layer adversely impacted cooking quality.…”

“…The WMR was obtained by removing the entire bran layer from brown rice (Fig. 1B), leaving only the starchy endosperm (Wu et al, 2014). Non-starch nutrients and nutraceuticals such as proteins, minerals, dietary fibre, fatty acids and phenolic compounds are largely concentrated in the bran layer (Das & Singh, 2015;Martini, D'Egidio, Nicoletti, Corradini, & Taddei, 2015;Monks et al, 2013;Walter et al, 2013).…”

“…Our previous study (Wu et al, 2016) demonstrated that the inner aleurone layer of rice bran only had a marginal influence on rice cooking quality, and theoutermost cuticular layer adversely impacted cooking quality. Partial removal of the cuticular layer from brown rice by lightly milling is adequate to achieve similar cooking quality with WMR and retain most of the bran layer (Wu et al, 2014(Wu et al, , 2016. It was also suggested that the shelf life of the resultant lightly milled rice (LMR; Fig.…”

“…1C) could be extended by inactivation of peroxidase in LMR grain using superheated steam (SS).The desirable physical and sensory properties of LMR, including required cooking conditions, appearance, texture and microstructure, were well preserved after SS processing (Fig. 1E) (Wu et al, 2014). However, information about the effect of SS processing on the chemical composition and potential nutritional attributes of LMR is still lacking, including fatty acid composition, antioxidant activity, phenolic compounds and the molecular structure and digestibility of starch.…”