In Vitro Digestion Products of Fats in Sorghum/Rice Mixture and Their Oxidative Stability

Abstract

In order to investigate the in vitro digestion products of fat in the sorghum and rice mixture and its oxidative stability, sorghum and rice were compounded and cured in 1:4 and 1:1 mass ratios to simulate in vitro digestion. The fat digestion products of the sorghum and rice mixtures were analyzed qualitatively and quantitatively by gas chromatography-mass spectrometry (GC-MS), and their oxidative stability was investigated using lipid peroxide values and malondialdehyde concentrations as indicators. The results showed that, the 1:1 and 1:4 compounded rice contained 25 kinds of fatty acids after digestion by gastrointestinal fluid, of which the major fatty acids were palmitic, stearic, and linoleic acids. Unsaturated fatty acids accounted for 34.34% and 28.50% of the total. The contents of the essential fatty acids linoleic acid and α-linolenic acid were 91.41, 3.05 and 59.36, 1.83 μg/g, respectively. All were significantly higher than the rice group (P<0.05). In addition, the digested intestinal fluid peroxide values of 33.83 and 43.16 nmol/g and the malondialdehyde levels of 28.17 and 27.72 nmol/g in the 1:1 and 1:4 mixtures were lower than that in the sorghum for total oxidation. In summary, consumption of the sorghum and rice mixture improved the composition of dietary fatty acids consumed compared to rice alone, and it also reduced the accumulation of lipid oxidation products absorbed by the body compared to sorghum alone.

Keywords

• sorghum
• compound rice
• in vitro digestion
• fatty acids
• oxidative stability