Effects of drying methods and enzyme aided on the fatty acid profiles and lipid oxidation of rice by-products

ABSTRACT

We investigated the influence of hot air drying, far infrared radiation (FIR), and cellulase aided on the fatty acid composition and primary lipid oxidation of rice bran, rice husk, and ground rice husk. The lipid content was significantly reduced in the sample dried by hot air and FIR but remained unchanged in the cellulase-aided rice bran and husk. We found that oleic acid (18:1n − 7) and linoleic acid (18:2n − 6) increased in hot air- and FIR-dried rice bran. On the other hand, PUFA content was significantly reduced in the samples dried by hot air and FIR but remained unchanged in the cellulase-aided rice bran and husk. Cellulase aided gave significantly higher concentrations of SFA, MUFA, and PUFA in all samples than did hot air and FIR drying. However, the rice by-products dried with hot air and FIR had the lowest PV and TBA values during 30 days of storage. Our findings provide useful information for the pretreatment of rice by-products; consequently, more utilization of rice by-products will be extended for uses such as oil production.

KEYWORDS:

• FIR
• hot air
• oleic acid
• peroxide value
• rice bran

Acknowledgment

We thank Dr. Colin Wrigley for his valuable suggestions with the preparation of the manuscript.