Effect of dehulling, roasting, and cooking on the nutritional composition of Himalayan barnyard millet (Echinochloa frumentacea)

Background

The Himalayan Echinochloa frumentacea (barnyard millet) is believed to be a nutritionally rich crop but remains underutilized. It is generally used after removing its seed coat (SC) through dehulling, and for making some food items, it is roasted before cooking. Such pre-cooking processes, such as dehulling, roasting, and then cooking affect the nutraceutical potential of raw grains and food items prepared.

Results

The effects of processing techniques are determined in terms of variation in proximate properties, antinutrients, phytochemicals, and antioxidants. The processing methods significantly (p < 0.05) affected the nutraceutical potential of the processed form of barnyard millet. While comparing the nutritional properties of raw and dehulled barnyard millet, it was found that the SCs are nutritionally very rich, which are generally either discarded or become part of cattle feed. Vitamin C, E, alkaloids, and oxalate content were found to decrease after roasting. Cooking had decreased the carbohydrate, fat, vitamin C, vitamin E, alkaloid, oxalate, and iron content in both food types in comparison to the pre-cooking stage of the millet samples, while tannin content was found to have increased.

Conclusion

In this work, the variation in the nutritional parameters and phytochemicals of barnyard millet was studied during the processing steps, such as dehulling, roasting, and cooking. Roasting had shown a lesser impact on the selected nutritional properties of uncoated seeds, while cooking had changed some of the nutritional properties. The SC was also found to be nutritious, so it needs to be explored further for its efficient utilization.