Oxalate Free Averrhoa Carambola Fruit Juice and Wine Produced by a Modified Oxalate Route (Synthesis of Zinc Oxalate)

Carambola is highly valued for its fruits, especially the pulp which is used for a wide variety of domestic and industrial purposes. The Carambola fruit is a nutritious food containing acids, vitamins, phytosterols and other phytochemicals. The drinks (Fruit juice and fruit wine) from Averrhoa Carambola L. are specific due to their taste and flavor. However, they contain oxalate at concentrations which are not health promoting when consumed. We are taking this advantage to explore wine fermentation from Carambola fruit pulp by focusing on the effect of different parameters such as time of treatment for juice extraction, yeast inoculate for wine fermentation and secondary fermentation to wine quality, and to  precipitated the oxalate ions from the juice and wine using metal zinc ions as a fruit metal.  The main fermentation was done at 25o C in 13 days, and 1 week of secondary fermentation in dark bottle at 25o C. The wine produced was characterized for alcoholic content, pH, titratable acidity, Brix, and consumer acceptability while the precipitate (Zinc Oxalate) was characterized by FTIR and PXRD. The carambola fruit pulp juice and wine produced were of acceptable quality (clear, sweet, sparkling, smooth and flavoured) following the olfactory test. The drink had a pH of 4.02 and 11.2 %, alcohol content while the FTIR and PXRD results revealed that oxalate ions were precipitated from the juice and wine by zinc ions, and   after precipitation of the juice and wine, the oxalate concentration in the drinks were reduced to health promoting levels. Furthermore, the precipitation process did not affect the acceptability of the wine as the olfactory parameter were not actually affected