Effect of Yeast and Acetic Fermentation on Phytochemical and Antioxidant Properties of Jackfruit Pulp(Artocarpus heterophyllus L.)

Abstract

Jackfruit (Artocarpus heterophyllus L.) is one of the important tropical fruits in Malaysia, mainly used for fresh consumption because of its good source of energy, deliciously sweet in taste, proteins, dietary fiber, minerals and vitamins. To date, there is lack of fermentation study reported on jackfruit. Hence, the aim of this work is to evaluate the phytochemical content and antioxidant properties of fermented jackfruit which was subjected to acetic acid bacteria and yeast fermentation individually for a duration of 7 days. The changes in the pH value, brix value, total reducing sugar content, total phenolic and total flavonoid content were examined for both yeast and acetic acid fermented jackfruit samples. Few antioxidant activities such as ferric reducing antioxidant power (FRAP) value and 2,2-diphenyl -1picrylhydrazyl (DPPH) free radical scavenging activity were also analyzed to determine the differences in the respective properties of jackfruit pulp after being subjected to yeast or acetic acid fermentation. There is a slight change on brix value and DPPH free radical scavenging activity (31.05-33.17% radical scavenging activity) for both yeast and acetic acid fermented samples. However, acetic acid fermented jackfruit exhibited higher total reducing sugar content (23.24 mg glucose/mL) and total phenolics content when compared to yeast fermented jackfruit sample. Both yeast and acetic acid fermented jackfruit samples showed higher FRAP value (0.435 -0.48 mg ascorbic acid/mL) than unfermented jackfruit sample (0.372 mg ascorbic acid/mL) except for total flavonoid content which exhibited a decreasing trend after fermentation.