Ricebean Microgreens: Cultivation, Postharvest Storage, Proximate Composition, and Organoleptic Evaluation

Best Paper for Postharvest, Processing and Utilization, 52nd Crop Science Society of the Philippines (CSSP) Scientific Conference, August 18-19, 2022, Philippines

Best Presenter, 1st Institute of Crop Science Young Alumni Research Conference, December 15, 2022, UPLB

Exploring the potential of lesser-known native vegetable crops is a viable option to mitigate issues on food and nutrient accessibility and sufficiency in the Philippines. This study has developed techniques for rice bean or tapilan (Vigna umbellata) microgreens production and postharvest handling. Three rice bean morphotypes yellow-green (RBYG), greyed-orange (RBAO), and dark greyed-orange (RBRB) from a single seed lot were germinated in moist sterilized coco coir, maintained under ambient temperature (28±1°C), and subjected to white and red-blue light-emitting diodes (LED) lights. Harvesting was done at BBCH 13 prior to the first trifoliate formation 5 days after germination. In RBYG and RBAO morphotypes with 98±2% germination, the microgreens produced have an average height of 16±0.5 cm and a pair of lanceolate leaves which 26 mm long and 6 mm wide. While, RBRB produced abnormal seedlings. Microgreens under white light exhibited opaque white hypocotyl with purple pigmentation at the base while those under red-blue light have dark green hypocotyl with less purple pigmentation. Proximate analysis showed that 100g of fresh tapilan microgreens contain 6.44±0.6 g crude protein, 4.65±0.59 g total carbohydrate, 0.76±0.22 g crude fat, 0.99±0.115 g/ ash, and 87.5±0.5% moisture content. Furthermore, using the 9-point Hedonic scale, tapilan microgreens products served as raw, steamed, and fried lumpia got “8 = like very much” acceptability rating from 20 respondents aged 15-55. Freshly harvested samples in high-density polyethylene (HDPE) self-seal bags stored in 12±2°C refrigerator remained fresh and sturdy for 6 days. Conversely, those under the freezer at 3±2°C deteriorated after 2 days. Production of 1000 g of tapilan microgreens would cost around ₱500.00-600.00. Indeed, this exploration on the competence of rice bean microgreens provides Filipino households a safe, healthy, and cost-effective food option especially this time of pandemic.