The processing industry requires potato tubers with low levels of reduced sugars, glucose and fructose, which is responsible for the whiteness of the chip color. The objective of this research was to optimize and validate a simple, inexpensive, and precise enzymatic method to quantify glucose in potato tubers. This method will be useful in breeding programs to select clones for processing purposes with low levels of glucose. The validation procedure followed the recommendations described in INMETRO document DOQ-CGCRE-008 in 2003. The method was linear between 1.25 to 40µg of glucose in the sample. The quantification limit was 0.319mg g-1 of potato fresh weight. The linear working interval of the method started at the quantification limit and ended at 1.32mg g-1 of potato fresh weight. The average recovery in the extraction was 99.0%. The proposed method was used to determine glucose level in samples of ‘Macaca’ tubers, which ranged from 1.4 to 2.9mg g-1 potato fresh weight.
Solanum tuberosum L.; tuber quality; glucose; enzymatic kit; spectrophotometry