Physicochemical and functional properties of Maori potato flour

Maori potatoes (Taewa) are an underutilized genetic resource for improving potatoes. Physicochemical and chemical properties of whole potato (skin included) flours from 4 Maori potato varieties were compared to those of two modern potato varieties. Significant variations were obtained for chemical composition, in vitro antioxidant activity, swelling power, water solubility index, thermal and rheological properties, gelling, and in vitro starch digestibility among the potato flour samples. The contents of dietary fibers, lipids, minerals, and phenolics were higher in Maori potatoes, especially in the flour of Tutaekuri with purple skin and flesh. Correlation analysis suggested that swelling, and rheological and textural properties were significantly associated with the starch content of the potatoes. Principal component analysis was done on the composition and properties to evaluate the similarities and differences among the potato samples. All the Maori potato samples were different from modern potato samples. Moemoe and Kowiniwini flour samples had similar properties.