Postharvest aspects on bioactive compounds in yellow onion (Allium cepa L.).
Morgren L., Gertsson U., Olsson M.
5th International Postharvest Symposium . Volume of Abstract . Verona, Italy 6-11 June 2004, p.88
2004
บทคัดย่อ
Postharvest aspects on bioactive compounds in yellow onion (Allium cepa L.).
Onion (Allium cepa L.) contains high concentrations of flavonoids, especially quercetin, that has been proposed to have beneficial health effects which may be mediated by their antioxidative properties.Some results show that these phenolic compounds also may have anticarcinogenic effects and may prevent from cardiovascular disease.There is a large variation between the content of flavonoids in different onion cultivars.There are also indications that the amount of quercetin at harvest is affected by the growing conditions.Improving cultivation and storage technique could be one way of obtaining onions with a higher content of quercetin, thereby getting an onion which satisfy consumer preferences of a healthy product.In general, present strategies for fertilization of vegetables lead to higher concentrations of e.g. nitrogen in the plant than is needed for optimal growth.This has negative effect on the environment.At the moment it is certain how the fertilization affects the amount of healthy antioxidants in field grown vegetables.To obtain onions rich in bioactive compounds there are some critical steps in the pre-and postharvest handling.Onion cultivar, fertilization strategy, harvesting time, curing methods and storage conditions seem to be the factors that have most impact on the concentration of flavonoids.From a growers point of view it is of interest to know which growing and handling techniques that affect the quality and how much effort is needed to achieve this quality in comparison to cost, time needed and potential outcome.It is important to find an acceptable balance between environmental aspects, product quality and productivity for onion cultivation.Product quality includes both outer and inner quality, which means that the onion should have a good appearance and maintain its good health effects even after a long time of storage and transportation to consumer.