Potato Research

, Volume 37, Issue 1, pp 87-97

First online:

Characterization of pectic substances from two potato cultivars with different sensitivities to prewarming

  • J. S. QuinnAffiliated withKraft General Foods, Inc.
  • , H. W. SchaferAffiliated withDepartment of Food Science and Nutrition, University of Minnesota

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access


Potato cultivars Chieftain and Kennebec were prewarmed at 70°C for 15 min. prior to heating at 100°C for 18 min. in a water bath. Chieftain exhibited a large increase in fracturability upon treatment while Kennebec showed a smaller increase. Pectic substances of the two cultivars were sequentially extracted in water, sodium hexametaphosphate (0.5%), hydrochloric acid (0.05M, 50°C), and sodium hydroxide (0.05M, 5°C). The largest fraction isolated from both cultivars consisted of hydroxide-soluble pectic substances, and was followed by the acid-soluble fraction. Chieftain contained significantly greater amounts of the hydroxide-soluble fraction than Kennebec. Ion exchange chromatography revealed that the extracted pectic substances from the two major fractions consisted of a charged pectin chain with attached neutral sugars. Gel filtration chromatography revealed wide molecular size distributions for the isolated pectic substances. Pectic neutral sugar content for the hydroxide-soluble fraction (50% of total pectic substances) was greater for Chieftain than for Kennebec.

Additional keywords

Solanum tuberosum L. fracturability column chromatography