Effect of MAP on the accumulation of stachyose in the edamame and its modeling
Edamame, immature, green soybeans or young soybean, is consumed in many countries in recent years because of its nutritional benefits (Rizzo and Baroni, 2018). Due to its high respiration rate, the edamame loses its quality very rapidly after harvest. Nakano et al. (2014) reported that the stachyose, a member of raffinose family oligosaccharides, is accumulated in the edamame seed at the beginning of the quality deterioration and also demonstrated the possible use of the stachyose as the freshness indicator of the legumes. In the present study, the effect of modified atmosphere packaging (MAP) on the delay of the stachyose accumulation in edamame was investigated, and its modeling was also proposed. Edamame pods with different packaging conditions (oriented polypropylene film with the macro-holes pouch, MH; micro-perforated MA film pouch, MAP; OPP pouch without perforation, OPP) were stored at 10 ̊C for 16 days. From monosaccharide to tetrasaccharide, including glucose, fructose, sucrose, raffinose, and stachyose were analyzed using HPLC. The raffinose content of edamame under MAP/OPP showed almost constant value throughout the experiment. A slight increase in raffinose was observed under MH. The accumulation of stachyose under MH, MAP, and OPP was observed at 4-days, 7-days, and 16-days of the storage, respectively. Results show that the MAP/OPP can retard the accumulation of the stachyose when compared to the MH. The edamame stored with OPP pouch showed the off odor due to anaerobic respiration. These results proved the effectiveness of the MAP on the keeping freshness and quality of edamame. The accumulation of stachyose in edamame, including the delay factor (time required for the accumulation) under different packaging conditions, was modeled by the storage period and the oxygen concentration. The relationship between the accumulation of stachyose and the expression of the stachyose synthase-encoding gene was evaluated and modeled.
Iida, R., Kitazawa, T., Umehara, H., Thammawong, M., Nakano, K., Naznin, H.A., Orikasa, T., Ciptaningtyas, D., Nagata, M. and Shiina, T. (2021). Effect of MAP on the accumulation of stachyose in the edamame and its modeling. Acta Hortic. 1311, 257-262
young soybean, raffinose family oligosaccharides, stachyose, sugar metabolism, modified atmosphere packaging, gene expression