Protein quality of South African potatoes to inform dietary choices

Abstract

Protein content was determined using both the nitrogen to protein conversion factor of 6.25 and the summation of amino acids for four of the potato cultivars (Solanum tuberosum L.) most commonly consumed in South Africa. Protein content for the cultivars varied between 1.65 g/100 g and 2.14 g/100 g fresh-weight when using protein conversion and 1.64 g/100 g and 2.14 g/100 g when using the sum of amino acids. Significant differences were found between the amino acid contents of the different cultivars. Leucine had the lowest chemical score of essential amino acids. Protein quality was evaluated using various methods. Even though the protein content of the cultivars is low, it is of a high quality and can contribute to overall dietary protein consumption.