Efficacy of Some Plant Aqueous Extracts andWaxes in the Preservation of Some Fruits andVegetables

摘要

Aim: The preservative effect of waxes (paraffin and ester) in addition to buffers (pH 9 and 10) and aqueous extracts (P. biglobosa pod, G. senegalensis and B. aeyptiaca leaves) were studied on fruits and vegetables. Methodology: The preservative effects of the waxes was determined by treating fresh ripe tomatoes, peppers and oranges with buffer (pH 9, 10) for 2 minutes and wax for 3 minutes using the dipping method and for extracts, washing daily with 5mg/ml or 10mg/ml for 3 minutes. Controls were untreated and unwaxed. Number of days taken for fruits and fruit vegetables to deteriorate was recorded and compared. Results: Results showed waxing was highly effective on pepper (30 days), moderately effective on orange (26 days) and fairly effective on tomato (15 days). Among the waxes, paraffin was more effective (9 – 30 days) in increasing shelf life than ester (9 – 14 days) and the control (6-8 days). P. biglobosa extract application proved more effective (17 - 26 days) than Guera senegalensis (13 – 14 days), Balanites aegyptiaca (8 - 13 days) and the control (9-11 days) in extending the shelf life of the test fruits and vegetables. Statistically, significant differences (P > 0.05) exist between shelf life of tomatoes, oranges and peppers used as control and those subjected to treatments. Comparison of the preservative activity indicated paraffin wax > P. biglobosa > G. senegalensis > B. aegyptiaca > ester wax. Conclusion: Application of waxes and plant aqueous extracts to preserve seasonally available fruits and vegetables could provide a cheap and economically viable method of preservation that could be adopted by farmers in Nigeria, where storage facilities for such products are insufficient.