A study on the effects of natural preservative towards fiber enriched milk tablets at different storage conditions

This study was conducted to determine the effects of different ratio (0% w/w, 5% w/w and 10% w/w) of turmeric powder {Curcuma Longa) as natural preservative towards fiber enriched milk tablets' color stability and fungal/microbial growth at light and dark storage conditions. Tablet samples prepared are made by using 5 different fiber enriched materials which are carrots, spinach, mango, watermelon and dragon fruit. Natural preservatives (0% w/v, 5% w/v, 10% w/v) were added to the sample powders and were compressed into tablets by using a tableting machine. Tablet samples prepared were stored in a lighted storage room while another set of samples will be stored in a dark storage room. All samples' initial color space (L*, a*, b*) were measured to determine its total color changes weekly for 2 months. After 2 months, the tablet samples were placed onto nutrient plates and left to cultivate for 3 days. The fungal/microbial growth were observed and recorded to study the effectiveness of natural preservatives as an antimicrobial material. Through this study, it is proven that turmeric has the potential to be a good natural food preservatives or antimicrobial substances. As the higher the percent of turmeric powder added to the tablet samples, the lower the area of fungal/microbial growth after 2 months. However, result shows an unstable color changes rate on most of the tablet samples regardless its preservatives content. Thus, in future studies, it is recommended to replace the natural preservatives used with other potential natural material like honey.