Effect of harvesting stage, form and duration of storage on some physico-chemical properties of Korarima (Afframomum (Braun) P.C.M. Jansen) collected from Masha Woreda, Sheka Zone, Southwestern, Ethiopia

Korarima, also called Ethiopian cardamom, is cultivated in the forest areas of southwestern part of Ethiopia. It is an underutilized spice crop with minimal research attention in the past. Therefore, a study was carry out to determine the appropriate harvesting stage, form, and duration of storage for an optimum quality of korrorima. The experiment consists of two different harvesting stages (fully mature green and mature red), three forms of storage (capsule, seed and powder) and three storage durations (0/without storing, 3 months storage and 6 months storage time) were arranged in factorial combination in randomized complete block design with three replicates. Results indicated that Fresh weight of capsules (FWC), dry weight of seeds (DWS), and seed to husk ratio (STHR) were highly significantly affected by harvesting stages (P < 0.01). Significant (P < 0.05) to very highly significant (P < 0.001) variation was also observed for seed quality traits such as volatile oil and oleoresin contents. The mean values of the fresh weight of capsule for mature green were 24.55 g and 23.28 g for mature red; dry weight of seed for mature green were 4.59 g and 6.45 g for mature red; and seed to husk ratio for mature green was 2.65 g and 3.38 g for mature red. Whereas, the available moisture content per sample ranges 15.08%–17.86%; crude protein 7.43%–9.39%; Volatile oil content ranged from 2.50 (v/w %) to 4.80 (v/w %) and oleoresin from 5.06 (v/w %) to 9.93 (w/w %). The variation may be linked to the moisture content and accumulation of different assimilates. Furthermore, level of exposure to higher temperature and free reactive oxygen might have created a significant variation between samples during the storage time. Fully mature green stage harvesting was found more recommendable and acceptable but fails to retain its intrinsic quality during long storage. Prolonged harvesting reduces most of the intrinsic quality of the A.corrarima. Storing for extended time in the form of powder may lead consumers to loss most quality traits than storing in the form of capsule.