Sprout inhibition in garlic (Allium sativum) and onion (Allium cepa L.) by gamma irradiation. Part of a coordinated programme on pre-commercial scale radiation treatment of food

With the aim of verifying the possibilities and circumstances of sprout inhibition and storage life extension of onion and garlic by gamma irradiation, onion bulbs of variety Valenciana Sintetica 14 and garlic bulbs of a coloured locally grown variety were subjected to irradiation with 3 Krad of 60Co gamma rays. The dose rate was 2440 rad/min; the irradiation conditions warranted a Dsub(max)/Dsub(min) ratio of 1.25. The irradiated bulbs and control samples of non-irradiated bulbs were investigated for a period of 270 to 330 days. Weight loss, external and internal sprouting, signs of decay, and the percentage of commercial bulbs were observed with the following results. Weight loss was found to be less in irradiated bulbs than in controls - 22% against 40% for onion and 33% against 65% for garlic. The dose of gamma radiation employed was proved to be sufficient for sprout inhibition in both species and for partial inhibition of decay and softening. The aroma of garlic was not impaired by irradiation. For both products, gamma irradiation was found to prolong the period of commercial utilizability