ARS | Publication request: Effect of Storage Temperatures on Antioxidant Capacity and Aroma Compounds in Strawberry Fruit

Submitted to: Swiss Society Of Food Science And Technology
Publication Acceptance Date: March 5, 2004
Publication Date: September 1, 2004
Citation: Ayala-Zavala, J.F., Wang, S.Y., Wang, C.Y., Gonzalez-Aguilar, G., Montoya, L.C. 2004. Effect Of Storage Temperatures On Antioxidant Capacity And Aroma Compounds In Strawberry Fruit. Swiss Society Of Food Science And Technology 37 (2004) 687-695.

Interpretive Summary: Consumption of strawberries is beneficial to human health. In addition to the usual nutrients, such as vitamins and minerals, strawberries are also rich in anthocyanins, flavonoids, phenolic acids, and other natural antioxidants. However, very little information is available on the effect of postharvest handling, such as storage temperature or changes in these phytonutrients. We have conducted a study to investigate the effect of different storage temperatures on antioxidant levels as well as aroma compounds and overall quality of strawberries. We found that antioxidant levels, anthocyanins and total phenolic content increased during storage at 10 or 5 degrees centigrade and strawberries stored at 10 degrees centigrade had the highest amount of both antioxidants and aroma compounds. However, the overall quality and storage-life were best in fruit stored at 0 degree centigrade. These results indicate that manipulation of postharvest storage temperatures may result in different fruit quality. Commercially feasible technologies may be developed to enhance health benefits of strawberries. The results from this study will benefit growers, shippers, other researchers, and the general public. Knowledge gained from these experiments is helpful in technology transfer to maximize antioxidant content in foods for human consumption.

Technical Abstract: The antioxidant capacity (measured as oxygen radical absorbance capacity, ORAC), total anthocyanin, total phenolic, aroma compounds, and postharvest quality of strawberry fruit (Fragaria x ananassa cv. Chandler) kept at 0, 5 and 10C were investigated. Strawberry fruit stored at 10 or 5C showed higher antioxidant capacity, total phenolic, and anthocyanins than those stored at 0C. However, the postharvest life based on overall quality was longer at 0C than at 5 or 10C. The production of aroma compounds was markedly influenced by storage time and temperature. Individual aroma compounds were affected differently. For example, ethyl hexanoate, hexyl acetate, methyl acetate, and butyl acetate increased, while 3-hexenyl acetate and methyl hexanoate decreased during storage. In general, strawberries stored at 10 or 5C produced higher levels of these volatiles than those stored at 0C. In conclusion, strawberries stored at 0C retained an acceptable overall quality for longest storage duration, however, berries stored at temperatures higher than 0C showed higher aroma compounds and antioxidant capacity during the postharvest period.