Gamma radiation affects the growth process of the common onion in several ways.
A good deal of research has gone into determining ways of improving the quality and shelf life of common foodstuffs. The onion, a staple of many culinary traditions, withstands long periods of storage following harvest. Scientists have measured the capacity of gamma rays to extend an onion's shelf life before the onion begins to rot, lose weight, sprout or otherwise become unmarketable. In addition, radiation has been found to beneficially alter other onion properties, such as its pungency and flavor. Does this Spark an idea?
Weight Loss
According to experiments done at the NWFP Agricultural University in Peshawar, Pakistan, onion bulbs exposed to gamma radiation showed less incidence of weight loss while being stored, as compared with regular bulbs. Of bulbs exposed to intensity levels of 2, 4, 6 and 8 Kr (kilo rad), the 8 Kr exposure experienced the smallest degree of weight loss, by only decreasing by 28.5 percent. In a separate trial published in the Journal of Food Processing and Preservation, gamma rays were again shown to reduce weight loss during an onion bulb's shelf life, as well as improving their "marketability" or appearance. According to research done at the Universidad Nacional del Sur of Argentina, irradiated onion bulbs evidenced 22 percent less weight loss, compared with 40 percent among non-irradiated bulbs. In addition, irradiated garlic lost only 33 percent of its weight, versus 65 percent among non-irradiated normal varieties.
Firmness
According to the NWFP experiments, onion bulbs exposed to gamma rays evidenced decreased firmness, compared with bulbs grown under normal conditions. Those exposed to 8 Kr of radiation displayed the least change in firmness.
Rot Attack
The same NWFP trials demonstrated far lower occurrences of rot attack among onion bulbs exposed to gamma rays. Those exposed to 6 or 8 Kr levels showed the smallest change in rot-attack incidents, with 6.3 percent less tendency to rot than those onions grown under normal conditions. According to the Universidad Nacional del Sur's research, gamma radiation partially inhibited decay and softening among both onions and garlic bulbs. In addition, it delayed internal or external sprouting.
Pungency
According to findings published in the Sarhad Journal of Agriculture, gamma radiation can also affect the pungency of onion bulbs. Those bulbs in the control group, exposed to no gamma radiation, had the greatest pungency, whereas the bulbs exposed to 8 Kr of radiation evidenced the least pungent flavor. On the other hand, research at the Universidad Nacional del Sur of Argentina found that radiation had negligible effects on the onion's acidity, measured in terms of its ascorbic acid content.
Tags: bulbs exposed, onion bulbs, exposed gamma, gamma rays, weight loss
