Contribution of endogenous minor components in the oxidative stability of rice bran oil

• Published in: Journal of food measurement & characterization 2023-02, Vol.17 (1), p.187-210
• Main Authors: Ali, M. Abbas, Chew, Sook Chin, Majid, Fadzilah Adibah Abdul
• Format: Article
• Language: English
• Subjects: Antioxidants; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Chlorophyll; Constituents; Engineering; Fatty acid composition; Fatty acids; Food Science; High resistance; Metal concentrations; Nutritive value; Oxidants; Oxidation; Oxidation resistance; Oxidative stress; Oxidizing agents; Phenols; Photooxidation; Reduction (metal working); Review Article; Rice; Rice bran; Rice bran oil; Squalene; Sterols; Structural stability; Vegetable oils
• ISSN: 2193-4126; 2193-4134
• DOI: 10.1007/s11694-022-01602-z

Rice bran oil (RBO) is widely accepted product of rice bran which possesses exceptional properties compared to other commonly used vegetable oils. Although the oxidative stability of RBO has been described in some research articles, main factors which make it capable of maintaining its higher stability under various oxidative stresses has not been reviewed yet. This review addresses currently published information on the contribution of mainly minor constituents on the oxidation stability of RBO. The high resistance to oxidation displayed by RBO seems to be related mostly to the presence of well-balanced fatty acid composition (FAC) and powerful antioxidants. The presence of γ-oryzanol (1.50–2.90%), its synergic activity and of tocols may be the major factors in maintaining high RBO stability. The structural features and concentration of other minor constituents such as sterols, phenolics, squalene etc. in RBO are also responsible for retarding oxidation of RBO. But the high concentration of free fatty acids in RBO negatively impact on oil oxidation and quality. The operating parameters in RBO refining steps, should be optimized to ensure minimal loss of such useful components to prevent reduction of stability. Metal concentration was not correlated with stability of the RBO, though it act as pro-oxidants. Chlorophylls content in RBO triggers oxidation degradation through photo-oxidation. However, the stability is not just a function of individual components but may be a cumulative effect of various antioxidants. This study may benefit comprehensive understanding nutritional values and provide suggestions for retention of minor components in RBO.