Discipline: Chemistry and Chemical Sciences
Subcategory: Chemistry (not Biochemistry)
Arrieyana Cartier - Virginia State University
Co-Author(s): Zully Perez, University of Nebraska-Lincoln
The color quality of juices from pigment-rich fruits undergoes deterioration during thermal processing. vitamin C fortification in juice prevents oxidation and enhances nutritional levels, however, it can also degrade the color of pigment rich juices by oxidizing anthocyanins. It is theorized that byproducts from vitamin C oxidation, especially hydroxyl radicals, play a vital role in anthocyanin degradation resulting in the color quality. Gallic acid has been reported as a potential antioxidant to mitigate the anthocyanins degradation. Therefore, the objectives of this study were to determine the effect of temperature and vitamin C fortification on anthocyanins and color degradation in tart cherry juice, and to evaluate the protective effect of gallic acid against the detrimental effect of vitamin C fortification. Montmorency tart cherry juice concentrate was used in this study. The 15x diluted juice was fortified with different vitamin C levels (from 20-100 mg/100 mL) and 300 mg/100 mL of gallic acid added. Then the juice was pasteurized for 1 minute at 75°C, 85°C, and 95°C. Juice was analyzed for total anthocyanin, total phenolic content, red color intensity, and browning index. Decreased levels of anthocyanin and red color intensity were observed with increased concentrations of vitamin C fortification and pasteurization temperature. Gallic acid reduced color degradation and browning index significantly with pasteurization at 85°C and 95 °C, but was not effective at reducing anthocyanin degradation with the treatments in this study. The results of this study demonstrated that gallic acid could be used by the juice industry to improve color and anthocyanin content. Future work should include a shelf life study to determine the long term effects of gallic acid and a sensory panel to determine consumer perception.
Funder Acknowledgement(s): The author would like to acknowledge Sunisa Roidoung, Dr. Siddiq, and Dr. Dolan for the guidance and mentorship during the course of this project as well as the Michigan State University Summer Research Opportunities program for the opportunity.
Faculty Advisor: Kirk Dolan, dolank@anr.msu.edu
Role: My lab partner and I completed the entire research project with the assistance of our adviser. I worked on every aspect of the project which included dilution of the juice, fortification with ascorbic acid, pasteurization and the antioxidant and color cauterization test. I also analyzed the data using MiniTab using code given to me by the graduate student mentoring us on the project.