Physicochemical and nutritional traits of sweet potato (Ipomoea batatas (L.) Lam) landraces grown in traditional farming systems

Abstract

In response to global concerns over food scarcity, the sweet potato (Ipomoea batatas (L.) Lam) has emerged as a promising alternative due to its rich composition of carbohydrates (starch), protein, fiber, vitamins, and minerals. This study aims to assess the physicochemical characteristics and nutritional content of different sweet potato landraces cultivated in Yucatan, Mexico. The study involved the evaluation of eight landraces of sweet potato cultivated in traditional farming systems, assessing both physicochemical and proximate composition variables, and determining the starch yield, starch color, protein content, swelling degree, and starch solubility index. The sweet potato landraces showed values ranging from acidic to slightly neutral pH (6-6.4). The yellow sweet potato II, purple sweet potato, and pink sweet potato landraces displayed high levels of total soluble solids with a range of 12.5 to 14.33 °Brix. Significant differences were observed in both peel and root pulp coloration. The pink, yellow, purple I, mamey, yellow II, and purple sweet potato landraces, presented elevated percentages of carbohydrates (85.0% to 89.0%), fats (1.1% to 1.5%), protein (3.5% to 5.1%), fiber (4.0% to 5.0%), and ash (3.5% to 4.0%). The mamey sweet potato and pink sweet potato landraces showed higher starch yields. Swelling power and starch solubility index peaked at a temperature of 90 °C. These results highlight the significance of sweet potato landraces cultivated in Yucatan as a valuable genetic resource with nutritional potential, which can be included in the diet of people, genetic improvement and species conservation programs.