Document Type : Research Paper

Abstract

Irradiation is known to inhibit waste in stored garlic. Treatment time and optimum irradiation dosage are two key factors in achieving the least waste in this process. These two factors were investigated on white ecotype bulbs from Hamedan, Iran that were irradiated after harvest for 30 and 45 days using fast electrons at dosages of 0, 25, 50, 75, 100, and 150 Gy. Different properties of the garlic were measured bimonthly over eight months of storage under both cold and uncontrolled conditions. The results showed that sprouting was observed only in non-irradiated cloves and irradiated cloves showed no signs of external sprouting. Weight loss for non-irradiated bulbs was greater than for the irradiated cloves. The minimum weight loss for cold storage was less than 1% per week at dosages of 50 Gy and higher. For uncontrolled storage, this minimum was achieved at dosages of 75 Gy and higher after 300 days. Total pyruvate, particularly up to 120 days of storage, increased sharply and there was no significant difference between them at the end of storage. While the firmness of irradiated cloves at the end of storage was not significant, the greatest firmness was observed for cold storage at dosages of 50 Gy and higher. For the uncontrolled conditions, this was measured at 75 Gy and higher. During storage, both color change and non-enzymatic pyruvate increased. More change was observed during irradiation at 45 days after harvest than at 30 days. Consequently, it concluded that for garlic bulbs in cold storage, 50 Gy is the optimum dosage of irradiation and, for uncontrolled conditions, 75 Gy is optimum. For both storage conditions, irradiation for 30 days after harvesting seems to be the most suitable period.

Keywords

Anon. 2010. Base statistics of Jihad -e- Agriculture Organisation of Hamedan. Office of Programming and management of statistics. Jihad -e- Agriculture Organisation of Hamedan Province. (in Farsi)
Anthon, G.E. and Barrett, D.M. 2003. Modified method for determination of pyruvic acid with dinitrophenylhydrazine in the assessment of onion pungency. J. Sci. Food Agric. 83, 1210-1213.
Bacon, J.R., Moates, G.K., Ng, A., Rhodes, M.J.C., Smith A.C. and Waldron, K.W. 1999. Quantitative analysis of flavour precursors and pyruvate levels in different tissues and cultivars of onion (Allium cepa). Food Chem. 64, 257-261.
Bayat, F. 2004. Effect of storage duration and conditions on the weight loss and quality of the garlic populations of Hamedan province. J. Agri. Eng. Res. 5(19): 49-62. (in Farsi)
Bayat, F. and Nosrati, A.H. 2009. Effect of harvesting time and drying at natural and artificial conditions on the storability of white garlic (Allium sativum L.) ecotype of Hamedan. J. of Medicinal and Aromatic Plants. 25(1): 49-63. (in Farsi)
Boettcher, H. and Guenther, I. 1994. Quality changes of dry garlic (Allium sativum L.) during long term storage. I. External quality. Nahrung. 38 (1): 61- 69.
Cantwell, M., Voss, R., Hanson, B., May, D. and Rice, B. 2000. Water and fertilizer management for garlic: Productivity, nutrient and water use efficiency and postharvest quality. Proceedings of the California ASA / Plant and Soil Conference, January 20. 16p.
Ceci, L.N., Curzio, O.A. and Pomilio, A.B. 1991. Effects of irradiation and storage on the flavor of garlic. J. Food Sci. 56(1): 44-46.
Ceci, L.N., Curzio, O.A. and Pomilio, A.B. 1992. Effects of irradiation and storage on the gamma – glutamyl transpeptidase activity of garlic bulbs cv. Red. J. Sci. Food. Agric. 59(4): 505-510.
Cho, H.O., Kwon, J.H., Byun, M.W. and Yoon, H.S. 1984. Batch scale storage of garlic by irradiation combined with natural low temperature. Korean J. Food Sci. Technol. 16(1): 66-70.
Croci, C.A. Curzio, O.A. 1983. The influence of gamma – irradiation on the storage life of “red” variety garlic. J. Food Process Pres. 7(3): 179-183.
Curzio, O.A. and Urioste, A.M. 1994. Sensory quality of irradiated onion and garlic bulbs. J. Food Processing Pres. 18 (2): 149–158.
Faraji, R. 1992. Principles of Food Preservation. Shiraz University. Iran. (in Farsi)
Freeman, G.G. and whenham, R.J. 1976. Effect of over winter storage at three temperatures on the flavor intensity of dry bulb onions. J. Sci. Food Agric. 27, 37.
Khan, I. and Wahid, M. 1978. Feasibility of radiation preservation of potatoes, onions and garlic in Pakistan. In “Food Preservation by Irradiation” Vol. 1. P.63, IAEA, Vienna.
Kwon, J.H. and Yoon, H.S. Sohn, T.H., Byun, M.W. and Cho, H.O. 1984. Effect of gamma irradiation dose and timing of treatment after harvest on the storability of garlic bulbs. J. Food Sci. 50(2): 379-381.
Kwon, J.H. and Yoon, H.S. 1985. Changes in flavor components of garlic resulting from gamma irradiation. J. Food Sci. 50(4): 1193-1195.
Kwon, J.H., Byun, M.W., Cho H.O. 1985. Effects of gamma irradiation dose and timing of treatment after harvest on the storability of garlic bulbs. J Food Sci. 50: 379-381.
Lustre, A.O., Roncal, R.A. Villaruel, F.G., Ang, L., Singson, C.C., Carmona, C.L. and DeGuzman, Z.M. 1982. The technological feasibility of gamma radiation for the extended commercial storage of agriculture crops, onion and garlic. Food irradiation for developing countries in Asia and Pacific. P. 127. IAEA. Vienna.
Matikkala, E.J. and Virtanen, A.I. 1965. g- glutamyl peptidase in sprouting onion bulbs. Acta Chem. Scand. 19, 1261.
McMurray. C.H. 1990. in Food irradiation: The challenge. Food irradiation and the chemist (Johnston D. E. and Steveenon M.H., Eds.). Royal Society of Chemistry. Cambridge. United Kingdom. 
Moreira, H.T., Villegas, M.I. and Cabrera, R.L. 1987. Browning and cooked flavor of garlic during dehydration. Technologia Quimica. 8(1): 31-36.

Morris, S. 2001. Fruit and vegetable postharvest and storage information. Sydney Postharvest Laboratory and Food Science Australia. CSIRO 2001. Available on: www.publish.Csiro.au.

Pellegrini, C.N., Croci, C.A. and Orioli, G.A. 2000. Morphological changes induced by different doses of gamma irradiation in garlic sprouts. Radiat. Phys. Chem. 57, 315-318.
Perez, M.B., Curzio, O.A., Aveldano, M.I. and Croci, C.A. 1998. Effects of gamma irradiation on the lipid composition of inner sprout of garlic. Radiat. Phys. Chem. 52, 113-117.
Perez, M. B., Aveldano, M.I. and Croci, A.C. 2007. Growth inhibition by gamma rays affects lipids and fatty acids in garlic sprouts during storage. Postharvest Biol. Tec. 44(2): 122-130.
Wahid, M., Khan,­S. andShah, H.1990. Effect of irradiation and storage on physico-chemical characteristic of garlic. Sarhad J. Agric. 6(4): 371-376.
Wall, M.W. and Corgan, J.N. 1992. Relationship between pyruvate analysis and flavor perception for onion pungency determination. Hort. Sci. 27, 1029-1030.
Weichmann, J. 1992. Postharvest physiology of vegetables. Translated by: Fallahi M. Barsava, Mashhad.
Whitaker, J.R. 1976. Development of flavor, odor and pungency in onion and garlic. Adv. Food Res. 22, 73-133.