Comparative Interpretation of Structural, Functional, Phytochemical and Pasting Profile of Coloured Variety Potato Flakes Prepared Using Different Drying Techniques

Abstract

The present study investigated the effects of different drying methods (drum and tray drying) on overall quality of potato flakes prepared from Lady Rosetta (LR) (white fleshed potato) and PP-1901 (purple potato) varieties. It was found that drum drying had more significant (p<0.05) effect in reducing the colour values of flakes. Drum dried (DD) samples showed higher values of water and oil absorption capacity than tray dried (TD) samples for both varieties. Purple variety flakes had significantly very high values of phytocompounds in comparison to white fleshed flakes. Regardless of the varieties, TD flakes had higher values of total phenolics, flavonoids and anthocyanin contents than DD which was attributed to more heat severity in case of drum drying. Also, ascorbic acid content and antioxidant activity were higher in TD samples. Higher retention of phytocompounds in TD samples was also confirmed using Fourier transform infrared spectroscopy. Due to more pregelatinisation, DD samples had the highest changes in its crystallinity and had the lowest value of pasting temperature indicating the lowest cooking temperature confirmed using X-ray diffraction and rapid viscoanalyser, respectively. Practical application: Potato flakes are utilised as an ingredient in extruded snacks, potato chips, soups, snack pellets, rolls or bakery products. Utilising coloured variety potatoes for developing flakes can give a healthier option to consumers. The present study is the first one to develop coloured potato flakes by using drum and tray dryer along with investigating their effect on the potato matrix. These dryers are widely adopted commercially from past many decades.