Research Article
Maria Bisamaza and Noble Banad
Abstract
The purpose of the study was to compare sun drying and solar drying as processing techniques to prolong the shelf life of African Indigenous Vegetables while preserving the nutritional quality. The two vegetables selected for the study were solanum aethiopicum (locally known as Nakati) and amaranthus lividus (known as Bbuga) because they are common staple vegetables and cheap and accessible to many people in Uganda. The fresh samples were tested for microbial load using the power plate technique. The sliced vegetables for sun drying and solar drying were sun dried and solar dried for 48 hours each and packaged in air tight polythene bags and stored at room temperature for up to 8 weeks. Ascorbic acid tests were also carried out using the titration method by Kirk and Swayer (1991) on fresh samples and on each pre-treated sample of each vegetable under study. Amaranthus lividus exhibited an intense colour which masked the end point. The results got were analysed using Gen stat as a statistical package using a 5% level of significance. The obtained results showed that there was a significant difference in the ascorbic acid content of the fresh samples, sundried samples and solar dried samples of the solanum aethiopicum. Fresh samples of the solanum aethiopicum had significantly the highest ascorbic acid content followed by the solar dried samples and finally the sun dried samples had the least ascorbic acid content. Furthermore, there was significant difference between the microbial loads for the fresh samples, sun dried samples and solar dried samples of amaranthus lividus and solanum aethiopicum. The fresh samples had the significantly highest microbial load followed by the sun dried samples and lastly the solar dried samples had the least microbial load. There was a significantly higher microbial load in the amaranths lividus than in the which solanum aethipicum could be attributed mainly to the larger surface area and handling. There was no pattern observed in the microbial load over the eight weeks of storage for both the solanum aethiopicum and amaranthus lividus.