The Effect of Processing on the Antioxidant Activities of Purple Onions (Allium Cepa L.), Bulb.

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W. C. Ijeoma
M. O. Enemali
K. K. Asogwa
C. A. Onwukeme
N. M. Nwodo


Onion (Allium cepa L.) is a common vegetable and is widely consumed all over the world. It has been used as a food and medicinal crop since ancient times; it is grown worldwide and because of its peculiar taste, unique flavor, highly valued aroma, and various health benefits, it is sometimes referred to as the “Queen of the kitchen”. Onions is traditionally used as fresh condiment, but recently, particularly in the year 2020, the scarcity of the commodity has led to a thought of processing and preserving it for the scarcity period. The present study was therefore, conducted to evaluate the effect of processing on the antioxidant activities of fresh, sun dried and oven dried purple onion bulb. Two processing methods which included sun-drying and oven-drying at 70oC were used. The antioxidant activities were determined using standard biochemical methods. The oven dried sample showed better antioxidant activities when compared to the other samples. The results of the parameters analyzed in this study, suggests that oven drying (70oC) is the most efficient method of processing and preservation of purple onion, since it gave the best results among the samples assessed. Therefore, it can be concluded that oven dried purple onions have enhanced antioxidant properties making it a good candidate for the prevention and therapy of array of diseases which meets consumer requirement of being readily available all seasons.



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How to Cite
Ijeoma, W. C., Enemali, M. O., Asogwa, K. K., Onwukeme, C. A., & Nwodo, N. M. (2023). The Effect of Processing on the Antioxidant Activities of Purple Onions (Allium Cepa L.), Bulb. The Bioscientist Journal, 11(2), 194-207. Retrieved from
Author Biographies

W. C. Ijeoma



M. O. Enemali



K. K. Asogwa



C. A. Onwukeme




N. M. Nwodo




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