RSUSSH 2020
IN20-230 Effect of Vacuum Drying Temperatures and Times on Color and Lycopene Content of Dried Gac Fruit (Momordica cochinchinensis Spreng.) Aril
Presenter: Nut Thephuttee
Rangsit University, Thailand
Abstract
Lycopene is the significant and the most abundant carotenoid in gac fruit aril. However degradation of lycopene can occur during drying and storage and is influenced by factors such as heat, oxygen, and light. This research aimed to determine the optimal condition for drying of aril using vacuum drier that limits aril exposure to oxygen. Aril was dried at 50, 70 and 90°C under 10 kPa vacuum, samples were collected every 2 h until their moisture content was less than 12% (wet basis) specified in the dried fruit standard. Properties of the dried aril were examined including moisture content, water activity, instrumental color, and percentage of lycopene retention. The time needed to achieve the required final moisture content when fresh aril was dried at 50, 70 and 90°C were 18, 10 and 8 h, respectively. Properties of the dried aril were found to be depended on the drying conditions. It was found that the optimum temperature and time for drying of gac fruit aril were 90°C and 8 h. The attained moisture content was 7.46% (wet basis) and water activity was 0.449 respectively. The dried aril exhibited the highest redness (a*) and yellowness (b*) values compared to other conditions. The retention of lycopene was 27.18%, almost similar to other conditions. The results also revealed the possibility of using vacuum sealed laminated aluminum foil bag stored at ambient temperature as an option for storage of the dried aril resulting in the lycopene retention of 92.14% after 4 weeks.
Citation format:
Thephuttee, N., Apisittiwong, T., Chaiyot, J., & Chanmuang, J.. (2020). Effect of Vacuum Drying Temperatures and Times on Color and Lycopene Content of Dried Gac Fruit (Momordica cochinchinensis Spreng.) Aril. Proceeding in RSU International Research Conference, May 1, 2020. Pathum Thani, Thailand.QUESTIONS & ANSWERS
For my question, why you did not study the temperature at 80 C or 100 C? How long is suitable storage time in general?
How did you determine lycopene content?
(1) For my question, why you did not study the temperature at 80 C or 100 C? How long is suitable storage time in general?
Drying at elevated temperatures of 70 and 90°C were included in this study to see the possibility of maximizing evaporation and drying rates and minimizing drying time, since lessening production time while increasing production rate is significant in scaling up a process for commercialization. If the qualities of aril dried at higher temperature especially its lycopene content are acceptable comparing to the one dried at lower temperature, this will be a decent production choice for manufacturer.
Storage test was performed only for a limited time (4 weeks) to initially evaluate the possibility of using a combination of this container option and storage condition for storage of a vacuum dried aril, hence in the future longer storage study should be conducted to further reveal the lycopene stability of vacuum dried aril under vacuum storage.
(2) How did you determine lycopene content?
Lycopene content was determined by spectrophotometric method as described by Nagata and Yamashita (1992) and Bhumsaidon and Chamchong (2016). Aril samples was extracted by mixed solvent of acetone and hexane (4:6 by volume). Aril extract was homogenized, let the sediment settled then collected a supernatant layer. The light absorption values at 453, 505, 663 and 645 nm wavelength were recorded using a UV-visible spectrophotometer.