Approximately half of the potatoes (Solanum tuberosum L.) grown in North America are consumed as French fries or potato chips. For the processors who make these products, fry color is a vitally important quality characteristic. The preferred light fry color depends on low reducing sugar concentrations in the raw tubers (Burton et al., 1992; Mazza, 1983). Although researchers and industry experts have long believed that elevated CO2 in the storage atmosphere results in increased reducing sugars and hence darkening of fry color, it has recently been shown that this is true only when a trace concentration of ethylene gas is also present (Daniels-Lake et al., 2005b).
Ethylene gas can increase reducing sugar concentrations in potato tubers, leading to darkening of fry color (Daniels-Lake et al., 2005a; Haard, 1971; Prange et al., 1998). The ethylene blocking compound 1-methylcyclopropene (1-MCP) has been shown to prevent darkening of potato fry color attributable to ethylene (Prange et al., 2005). It was hypothesized that 1-MCP may prevent darkening attributable to the interaction of ethylene and CO2, and trials were conducted to test this hypothesis.
Burton, W.G., van Es, A. & Hartmans, K.J. 1992 The physics and physiology of storage 608 727 Harris P.M. The potato crop: The scientific basis for improvement. 2nd Ed Chapman and Hall London, UK
Daniels-Lake, B.J., Prange, R.K., Nowak, J., Asiedu, S.K. & Walsh, J.R. 2005a Sprout development and processing quality changes in potato tubers stored under ethylene: 1. Effects of ethylene concentration Amer. J. Potato Res. 82 389 397
Daniels-Lake, B.J., Prange, R.K. & Walsh, J.R. 2005b Carbon dioxide and ethylene: A combined influence on potato fry color HortScience 40 1824 1828
Prange, R.K., Daniels-Lake, B., Jeong, J.-C. & Binns, M. 2005 Effects of ethylene and 1-methylcyclopropene on potato tuber sprout control and fry color Amer. J. Potato Res. 82 123 128
Prange, R.K., Kalt, W., Daniels-Lake, B., Liew, C.L., Page, R.T., Walsh, J.R., Dean, P. & Coffin, R. 1998 Using ethylene as a sprout control agent in stored ‘Russet Burbank’ potatoes J. Amer. Soc. Hort. Sci. 123 463 469