ABSTRACT

Melons (Colocynthis citrullus L.) are widely grown in Nigeria and other parts of West Africa for their seeds, which are rich in proteins and oil (Oyenuga and Fetuga 1975; Oyolu 1997; Onuora and King 1983). The Nigeria melon fruit harvest is processed by the wet method in which the melon pod is subjected to mechanical and biolOgical operation in order to separate the seed from the mesocarp (pulp) (Offonry and Achi 1998). The process is typically carried out by solid substrate fermentation of the pod at ambient temperature (28-30°C) for a period of days in covered heaps. At the end of the fermentation period, the seeds are scooped out, washed with water and spread on a concrete platform (Badifu and Ogunsua 1991). Disintegration of the pod tissue structure results in hydrolysis and subsequent liquefaction of the mesocarp leading to easy recovery of the seeds from the watery waste. The processing of melon pods for seed recovery resembles that of cocoa and coffee or cassava tubers (Passos et al 1984; Adegoke and Babalola 1988; Rolz et al 1988). Although the fermentation appears functional in pulp tissue disifltegration for seed removal, the role of the microflora remains to be determined from the involvement of some microorganisms as reported earlier (Obeta and Abriba1994; Offonry and Achi 1998), there is little available information regarding the role of microorganism in melon pod retting. According to Chesson (1980) soft rot represents the most striking  indication of pectic enzyme activity. Of the pectic enzymes, endopoly- galac- turonase and pectin esterase are produced by a wide variety of microorganisms, and both enzymes are thought to mediate the soft rot process (Fogarty and Ward 1974).