Online

Lu, Jinglin

Nutrition and Food Sciences

2020

M.S.

Food products from coconut fruits are delicious and nutritious; the coconut water could be directly used as a sports drink; whereas the meat can be processed to coconut milk, coconut puree and other products that are rich in medium fatty acids that can be burnt quickly to provide energy to the body. In recent years, products that incorporated the probiotics with coconut have been developed, however the texture and nutritional qualities were not satisfied. The purpose of the study was to create a functional coconut yogurt using polymerized whey protein (PWP) as a gelation agent to achieve a better mouthfeel and also increase the protein content of the final product. In the preliminary studies, different ratios of PWP/stabilizer system were tested to optimize the formulation. After the formula was finalized, three groups including control yogurt, PWP fortified yogurt and Ca/vitamin D fortified yogurt of 3 trials were made for further analysis. The chemical composition of the coconut yogurt including protein, fat, minerals, total solids and ash were analyzed. A sensory evaluation was also conducted to compare the lab samples from each group with the commercial samples. Result showed that there was no difference of yogurt properties within three lab groups except for the firmness. However, the lab groups had a significantly (P<0.05) higher score for most properties than commercial group. pH values, viscosity and probiotics survivability were also analyzed weekly during the 8 weeks of storage. The pH significantly increased (P<0.05) for all groups, whereas the viscosity showed a slow but significant decrease in all groups (P<0.05) with the same decreasing rate (P>0.05). At the last week of study, only Lactobacillus paracasei were above the therapeutic level in all three groups. Lactobacillus acidophilus did not reach that level at the first week of storage. The difference of survivability among three groups were all significant different (P<0.05).