Changes in Flavor Precursors, Pungency, and Sugar Content in Short-Day Onion Bulbs during 5-Month Storage at Various Temperatures or in Controlled Atmosphere
Article first published online: 13 JAN 2012
© 2012 Institute of Food Technologists®
Journal of Food Science
Volume 77, Issue 2, pages C216–C221, February 2012
How to Cite
Yoo, K. S., Lee, E. J. and Patil, B. S. (2012), Changes in Flavor Precursors, Pungency, and Sugar Content in Short-Day Onion Bulbs during 5-Month Storage at Various Temperatures or in Controlled Atmosphere. Journal of Food Science, 77: C216–C221. doi: 10.1111/j.1750-3841.2011.02529.x
- Issue published online: 17 FEB 2012
- Article first published online: 13 JAN 2012
- MS 20110984 Submitted 8/12/2011, Accepted 10/24/2011.
- Allium cepa L. fructose;
- pyruvic acid;
Abstract: Short-day onion bulbs (cv. TG 1015Y) were stored in 1% O2, 99% N2 air at 5 °C (controlled atmosphere [CA]), or in ambient air at 5, 24, or 30 °C, for 5 mo. Changes in flavor precursors, pungency, and sugar content were investigated. After 5 mo of storage, 1-propenyl-L-cysteine sulfoxide concentrations increased continuously at 5 °C, gradually decreased in CA, slightly increased for 3 mo, and returned to initial levels at 24 °C and decreased below initial levels at 34 °C. Methyl-L-cysteine sulfoxide concentrations remained unchanged in all storage conditions. Onion pungency levels significantly increased at 5 °C, and decreased at 30 °C. Storage in CA and at 24 °C resulted in some fluctuations in pungency but the levels remained similar to initial levels. The calculated pyruvic acid concentrations were approximately 1.0 μmole/mL higher than the measured concentrations, and showed an increase at 5 °C and a slight reduction at 30 °C, consistent with the pungency results. Storage at 5 °C and in CA resulted in slight increases in fructose and glucose concentrations for 3 to 4 mo with subsequent rapid decreases, while sucrose concentrations remained unchanged. However, at 24 and 30 °C, fructose and glucose concentrations continuously decreased, accompanied by a continuous increase in sucrose concentrations. Storage in CA maintained the quality of onions best, as evidenced by the smallest changes in flavor precursors, pungency, and sugar concentrations, while storage at 5 °C resulted in increased pungency. Storage at 24 and 30 °C was tested for the purpose of comparison only; these temperatures are not recommended for commercial storage.