Water vapor resistance (WVR), antimicrobial properties and color analysis of cassava starch-based edible coating with turmeric oil

This study set out with the aim of assessing the properties of cassava starch edible coating incorporated with turmeric oil at different %w/v of cassava starch and turmeric oil concentrations. Properties that had been investigated in this report were water vapor resistance (wvr), antimicrobial properties and color analysis of coated apple slices. Cassava starch solutions was gelatinized at temperature of 70 oC-80 oC for 40 minutes. Glycerol act as plasticizer and turmeric oil was added to the solution at different concentrations. For WVR, Royal Gala apples (Malus domestica) were sliced at equal size and placed in dessicator at relative humidity of 98% followed by 33.5% relative humidity to calculate water vapor loss to the environment. The findings suggest that as high concentration of turmeric oil can highly reduce moisture loss. Increasing %w/v of cassava starch may also reduce moisture loss but the results were less obvious. Antimicrobial properties of the film was evaluated by culturing microorganisms on the surface of the apple slices on Plate Count Agar (PCA) for bacteria and Potato Dextrose Agar (PDA) for yeast and molds. Again, as turmeric oil concentration increase, less colonies were formed. However, increasing turmeric oil concentration may negatively affect the fruits flavor, odor and color.