Challenges and Countermeasures in Measuring Molecular Species of Characteristic Ingredients in Rice Bran Oil: Toward the Development of High-Quality Rice Bran Oil

Rice bran oil has attracted increasing attention not only for its nutritional ingredients, such as triacylglycerol with a well-balanced essential fatty acid composition, but also for its functional ingredients such as plant sterol, vitamin E, and γ-oryzanol. However, their accurate evaluation remains challenging because these ingredients exist as mixtures of structurally similar molecular species. This review introduces (1) the total measurement of triacylglycerol molecular species using near-infrared spectroscopy, (2) detailed individual measurement of γ-oryzanol molecular species using liquid chromatography/mass spectrometry (LC/MS), and (3) insights into the absorption and metabolism of γ-oryzanol molecular species using LC/MS. These technologies and insights are expected to ensure the health functionality of rice bran oil and to contribute to more efficient, high-quality rice bran oil production.