Abstract
The aim of this study was to determine some design-related properties of Irish potatoes commonly grown in Nigeria that may be useful in designing, handling and processing equipment of the product. Two varieties were selected: Nicola and Diamant. The measured properties were length, width, thickness, bulk density, solid density and angle of repose. Other parameters were arithmetic mean, geometric mean, surface area, volume, porosity and kernel weight. The mean length, width and thickness obtained for Nicola variety were 66.5, 37.3 and 32.4 mm respectively; while 57.4, 35.2, and 31.7 mm were obtained for Diamant, respectively. The mean angle of repose of Nicola and Diamant varieties were 27.20 and 26.40°, respectively. Mean roundness of Nicola and Diamant varieties were also obtained as 0.6 and 0.7 respectively. The mean surface area and volume of Nicola variety was determined to be 58.55 cm² and 42.61 cm³ while that of Diamant variety was 50.31 cm² and 34.08 cm³, respectively. Moisture contents of Nicola and Diamant varieties used were obtained as 76.3 and 85.9%, respectively. Mean hardness of Nicola and Diamant varieties was 1.52 and 1.7 HV, respectively; indicating that Diamant is a harder variety than Nicola. These properties may be useful and serve as a guide on major engineering design of handling and processing equipment.

Key words: Potatoes, Design factors, Nicola, Diamant.