Sugar and Amino Acid Content in Conventional vs. Organic Potatoes

Background and methodology:

Three sugars (glucose, fructose and sucrose) and two amino acids (free asparagine and free glutamine) were analyzed in 74 potato samples from 17 potato cultivars grown in 2002 at various locations in Switzerland and different farming systems. The potatoes came from a three-year on-farm experiment on 93 plots (20 organic, 31 integrated, 42 conventional farming system) focusing on quality aspects of Swiss potato production.

According to a defined sampling plan, 55 tubers from 55 plants were taken from each field, making up a total of about 5 kilograms per sample. Tubers (12−15) of a given sample were washed, and after the water was dripped off, cut lengthwise. From each tuber, one half was grated (holes of 2.5 mm × 7 mm, as typically used to prepare hash browns). The grated material was thoroughly mixed and used for all analyses. The potential of these potatoes to form acrylamide, a chemical known to cause cancer in animals and that occurs naturally in some foods when processed at high temperatures, was measured with a standardized heat treatment.


These potentials correlated well with the product of the concentrations of reducing sugars and asparagine. Glucose and fructose were found to determine acrylamide formation. The cultivars showed large differences in their potential of acrylamide formation, which was primarily related to their sugar content. Agricultural practice neither influenced sugars and free asparagine nor the potential of acrylamide formation. It is concluded that acrylamide content in potato products can be substantially reduced primarily by selecting cultivars with low concentrations of reducing sugars.


Amrein, T. M., Bachmann, S., Noti, A., Biedermann, M., Barbosa, M. F., Biedermann-Brem, S., Grob, K., Keiser, A., Realini, P., Felix Escher, F., & Amadó, R. (2003). Potential of acrylamide formation, sugars, and free asparagine in potatoes: A comparison of cultivars and farming systems. J. Agric. Food Chem., 2003, 51 (18), 5556–5560. Available on line at: