Phytosanitary irradiation for grapes and blueberries maintains quality during storage

Phytosanitary irradiation for grapes and blueberries maintains quality during the aging period

08/01/2016

While methyl bromide fumigation is in retreat due to the damage it causes to the ozone layer, low-dose ionizing irradiation is gaining ground as a promising phytosanitary method. New studies show that this treatment can also be effective on blueberries and table grapes, without compromising quality.

Blueberries Star, Jewel and Snowchaser and grapes Sugraone and Crimson Seedless were irradiated at a dose of 400 Gy (in a range of 400-590 Gy for blueberries and 400-500 Gy for grapes) and saved for three and 18 days under refrigeration, plus three days at room temperature.

"This experiment was designed to simulate transportation time by land between California and Mexico and shipping from California to Asia", Explained the scientists in charge of the study. The fruit was then evaluated in concentration of soluble solids, acidity, and weight loss. From these attributes, the results showed differences between the fruit varieties, but the researchers considered the effects of the treatment as "Not significant".

The American Society for Horticultutral Science (ASHS) study also involved sensory tests in which consumers evaluated fruits according to their appearance, taste, texture and taste in general. "Steadiness was the first attribute affected by irradiation for the two grape varieties, but sensory tests could not determine whether consumers preferred irradiated or controlled fruit", said the authors Jonathan Tong, Cyril Rakovski and Anuradha Prakash.

"However, the scores for the flavor were higher in the irradiated berries than in the controlled ones after storage, suggesting a decline in the quality of the controlled blueberries", the scientists said.

The authors noted that the research showed that in terms of quality, irradiation to 400 Gy can keep cranberries and table grapes during transport, distribution and storage needs for overseas markets. "Our results show that both blueberries and grapes have a high tolerance to phytosanitary irradiation, and that the storage affects their quality more than irradiation", they concluded.

Source: Fruit Portal