Stepwise blanching

It has been stated that the differences in optimum conditions for stepwise blanching proposed by various researchers are due to the levels of PME enzyme activity occurring in the different potato varieties used, and that this is affected by the maturity of the potato and the season. Canet et al. (2005c) kept potato tubers (cv. Kennebec) in refrigerated storage, and firmness and PME activity were periodically sampled over a period of 80 days. The PME activity of potato tissues blanched at 60, 70, and 80°C for varying periods of time was measured (Figure 7.4a). 

Canet, W., Espinosa, J., Ruiz-Altisent, M. (1982b). Effects of the stepwise blanching on the texture of frozen potatoes measured by mechanical tests. Refrig. Sci. Technol., 4,284-289. 

Pala, M. (1983). Stepwise blanching and its importance in freezing of vegetables. Refrigeration in the Service of Man. In Proceedings XVIth International Congress of Refrigeration , Vol. 3, pp. 631-638. Paris. 

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