Postharvest control

The economic implications of the mycotoxin problem and its potential health threat to humans have clearly created a need to eliminate or at least minimize mycotoxin contamination of food and feed. While an association between mycotoxin contamination and inadequate storage conditions has long been recognized, studies have revealed that seeds are contaminated with mycotoxins prior to harvest [185]. Therefore, management of mycotoxin contamination in commodities must include both pre- and postharvest control measures. 

Pariasca, J.A.T. et al.. Effect of modified atmosphere packaging (MAP) and controlled atmosphere (CA) storage on the quality of snow pea pods (Pisum sativum L. var. saccharatum). Postharvest Biol. TechnoL, 21, 213, 2000. 

Karabulut, O.A., Arslan, U. and Kuruoglu, G. (2004). Control of postharvest diseases of organically grown strawberry with preharvest applications of some food additives and postharvest hot water dips , Journal of Phytopathology, 152 (4), 224—228. 

Janisiewicz, W.J., Conway, W.S. and Leverentz, B. (1999b) Biological control of postharvest decays of apple can prevent growth of Escherichia coli 0157 H7 in apple wounds . Journal of Food Protection, 62, 1372-1375. 

Huyskens-Keil S, Prono-Widayat H, Liidders P and Schreiner M. 2005. Postharvest quality of pepino (Solarium muricatum Ait.) fruit in controlled atmosphere storage. J Food Eng 77(3) 628-634. 

Wright KP and Kader AA. 1997. Effect of controlled-atmosphere storage on the quality and carotenoid content of sliced persimmons and peaches. Postharvest Biol Technol 10 89-97. 

Gorny J, Hess-Pierce B, Cifuentes R and Kader A. 2002. Quality changes in fresh-cut pear slices as affected by controlled atmospheres and chemical preservatives. Postharvest Biol Technol 24 271-278. 

Ismail FA and Afifi SA. 1976. Control of postharvest decay in fruits and vegetables by irradiation. Nahrung 20(6) 585-592. 

Spadaro D and Gullino ML. 2004. State of the art and future prospects of the biological control of postharvest fruit diseases. Int J Food Microbiol 91 185-194. 

Postharvest approaches include control of moisture and temperature and proper ventilation. Treatment of contaminated corn with 2% ammonia reduces aflatoxin levels (Park et al., 1988), however this treatment changes the nutritional value of the seed and causes an ammonia odor and a change in color. Ammoniation is not an FDA-approved detoxifying procedure for crops intended for interstate commerce - it can be used only for crops to be used within the confines of a farm. Furthermore, ammoniation is a hazardous procedure for those conducting treatment. 

Post-harvest rots of avocado caused by fungal infection are an important but unsolved problem in quality control. Even with optimized post-harvest storage regimes about 20% of Hass avocado were found to be infected by postharvest rots in New Zealand. It is therefore surprising that no NMR/MRI investigations appear to have been reported on this quality factor. 

Controlled-atmosphere (CA) storage can extend the storage life of fruits and vegetables by decreasing metabolism and suppressing postharvest decay. 

Gunes, G. Liu, R. H. Watkins, C. B. Controlled-Atmosphere Effects on Postharvest Quality and Antioxidant Activity of Cranberry bruits. J. Agric. Food Chem. 2002, 50, 5932-5938. 

Conway, W. S., Leverentz, B., Janisiewicz, W. J., Saftner, R. A., and Camp, M. J. (2005). Improving biocontrol using antagonist mixtures with heat and/or sodium bicarbonate to control postharvest decay of apple fruit. Post-harvest Biol. Technol. 36, 235-244. 

Liu, Z., Zeng, M., Dong, S., Xu, J., Song, H., and Zhao, Y. (2007). Effect of an antifungal peptide from oyster enzymatic hydrolysates for control of gray mold (Botrytis cinerea) on harvested strawberries. Postharvest Biol. Technol. 46, 95-98. 

The tolerance limitation of fruit for irradiation establishes the maximum acceptable dose. If this dose controls decay organisms, the use of irradiation for a particular fruit may appear promising. Response to irradiation may be influenced by fruit maturity, variety, pre- and postharvest temperatures, handling, and extent of fungus growth. Climacteric fruits irradiated prior to the normal rapid increase in respiration usually show an immediate increase in respiration and the production of ethylene. These fruits are frequently retarded in ripening. 

Many investigators are seeking further improvements in the handling of fresh produce. Among methods receiving much attention are the use of postharvest chemicals, retardants of senescence, thermal treatment, controlled atmospheres, new packaging techniques, better temperature control in storage and transit, and irradiation. One method may work well with one fruit or a particular variety of fruit but not with another fruit. 

Application techniques can influence the efficacy of postharvest fungicides and, thus, alter the keeping quality of treated fruit. Application of sodium ortho-phenylphenate (SOPP) in a foam washer with an exposure time of only 15 to 20 sec is not as an effective method as a soak or drench treatment requiring 2-4 min (167). However, if proper pH control is not maintained, fruit may be burned with the soak or drench treatment (169, 170, 171). Applications of SOPP in wax were less phytotoxic (172). Within the last 14 years, development of the benzimidazoles, thiabendazole Q -(4 -thiazolyl) benzimidazole and. benoniyl Tmethyl 1-(butyl carbamoyl)-2-benzimidazole-carba-mat J, has led to the availability of fungicides with high... 

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