Microbial populations associated with the retting of melon pods ( Colocynthis citrullus L.) during seed recovery

The traditional process for the retting of melon pulp and microbiological characteristics in the recovery of melon seeds ( Colocynthis citrullus L.) were investigated. Melon pods were sliced open and exposed for seven days. The pulp underwent a natural fermentation that was characterised by the growth of microorganisms to 108–1010 cfu/g. The pH fluctuated between 4.8 and 5.1 with a lactic acid content of 0.72%. Bacillus subtilis, B. polymyxa, Lactobacillus fermentum, L. brevis and Streptococcus faecalis were the predominant microorganisms but, significant contributions were made by Staphylococcus saprophyticus and Enterobacter cloacae. Penicillium, Aspergillus and Rhizopus species including the yeasts, Sacharomyces cerevisiae Candida krusei and Deboromyces hansenii were isolated from the fermentation. Growth of microorganisms was completely inhibited in antibiotic-treated samples indicating that the melon pods were the main source of microorganisms for the fermentation.     

Influence of storage on chemical,microbial and consumer acceptability of a milk-like product made from melon seeds

The storage stability of melon milk at room (30 ± 2 ^°C)and refrigeration (10 ± 2 ^°C) temperatures was determined by analyzing changes in the chemical, microbial andsensory properties of the milk stored for 7 days. Theresults showed that at both storage temperatures, solublesolids and pH of the milk decreased while titratableacidity increased with storage. The standard plate countsincreased appreciably while coliforms were absent in themilk with storage at both storage temperatures. The overallacceptability score of the melon milk dropped duringstorage, the drop being faster at 30 ± 2 ^°C than at 10 ± 2 ^°C. The milk samples stored at 30 ± 2 ^°C and 10 ± 2 ^°C were acceptable only within one and three days, respectively; thereafter, theywere unacceptable.