Characterization of Nutritional and Flavor Profiles of Aromatic Black Rice, India

Chakhao is an indigenous aromatic black rice variety from Manipur, India, valued for its distinctive flavor, high anthocyanin content, and associated health benefits. Despite its geographical indication status, limited information exists on how regional cultivation conditions influence its compositional attributes. This study characterizes and compares the nutritional composition, mineral content, volatile profile, and fatty acid methyl esters (FAMEs) composition of Chakhao sourced from five major cultivation regions in Manipur. Proximate analysis quantified moisture, protein, ash, fiber, fat, and carbohydrate content, whereas GC-MS/MS and ICP-MS were employed to profile volatile compounds, FAMEs, and mineral elements. Carbohydrates were the predominant macronutrient (73.88%-74.21%), with protein levels ranging from 10.19% to 10.89%. Potassium (238.14-348.42 mg/100 g) was the most abundant mineral, followed by magnesium (93.88-145.74 mg/100 g). Key volatile compounds such as hexanal, nonanal, butanal, and region-specific variations in azulene and 1-hexanol contributed to the characteristic aroma of Chakhao. Fatty acid profiling identified oleic acid (37.00%-44.04%) as the dominant monounsaturated fatty acid, linoleic acid (30.27%-35.84%) as the major polyunsaturated fatty acid, and palmitic acid (18.38%-20.51%) as the principal saturated fatty acid. This study provides the first integrative, region-wise biochemical assessment of Chakhao, highlighting its nutritional richness and aroma complexity, and emphasizing the need for standardized cultivation and processing practices to ensure consistent quality and support its valorization in functional food applications.