Vegetables controlled atmosphere storage

Weichmann J. 1986. The effect of controlled-atmosphere storage on the sensory and nutritional quality of fruits and vegetables. Hort Rev 8 101-127. 

Thompson, A. K. (1998). Controlled atmosphere storage of fruits and vegetables. CAB International, Biddles Ltd, Guildford and King s Lynn, UK, 201-203. 

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

Literature is scarce on the effects of controlled atmosphere (CA) and modified atmosphere (MA) storage on carotenoid content and colonr retention in yellow and red vegetables. Sozzi et al. (1999), reported a lower content in total carotenoids and lycopene in tomatoes, which had been stored in 3% O2 or 20% CO2 than after storage in air (control). No differences were fonnd after storage in low O2 and high CO2. When the samples were transferred to air, the total carotenoid and lycopene contents were lower in the tomatoes, which were subjected to different storage treatments from those stored in air all the time. 

Some fruit and vegetables are stored under atmospheres enriched in CO2 and with reduced levels of O2. These storage conditions have a marked effect on phenolic metabolism and phenolic composition. Thus, Williams pears stored in air accumulate more phenol ics than fruits stored under controlled atmospheres (1% C02-l% O2 and 3% C02-3%02). A controlled atmosphere, then, strongly reduces the ability of pears to synthesise phenolic compounds [153]. 

Methanethiol has a very low flavor threshold value (0.02 ppb in water 15), and possesses a strong, offensive, fecal-like odor (18). It also is readily converted to very unpleasant oxidized sulfurous off-flavor compounds with low detection thresholds, such as dimethyl disulfide and dimethyl trisulfide (18,25). Thus, suppression or modulation of methanethiol formation in cruciferous vegetables would le to a reduction of off-flavors associated with methanethiol-related compounds, and enhance the utility of controlled and modified atmosphere storage technologies for these vegetables. 

Salfveit, M. E. A summary of CA and MA requirements and recommendations for the storage of harvested vegetables. G. D. Blanpied, J. A. Barstch, and J. R. Hicks (Eds.), Proceedings of the Sixth International Controlled Atmosphere Research Conference, Ithaca, New York, USA, 2, 800-81 (1993). 

In addition to the traditional canning, freezing, pickling and dehydration processes, several new processing techniques have surfaced in recent years. Irradiation with gamma rays, storage with controlled and modified atmospheric environment, reverse osmosis and ultrafiltration will be discussed in subsequent chapters. The emphasis will be on chemistry of quality improvement of the processed fruit and vegetable products. 

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