Minimum number of samples to determine inadequate storage of potato cv. Markies to processing

Abstract

Potato tubers for frying are stored at low temperature to reduce sprout losses and diseases. The objective was to determine the minimum number of potato cv. Markies for sampling and identification of improper storage conditions. Potatoes cv. Markies tubers were stored at 6 and 8 °C for 180 days and fried. The potato chips coloring was visually determined based on USDA's international grade scale. The repeatability coefficients were estimated by the analysis of variance methods (ANAVA), main components (MC), based on the correlation matrix (PCCo) and covariance (PCCv) and structural analysis (SA) based on the correlation matrix. The color of the potato chips cv. Markies differed with the storage temperature. The minimum number of sticks needed to predict inadequate storage of potato chips for frying at 99% reliability is 37, 50, 50 and 50% and with 95% repetibility is 7, 10, 10, 10 and 10 for the methods of ANOVA, PCCo, PCCv and SA, respectively. The difference in color of the sticks with the storage temperature allows the application of the repeatability coefficient and the indication of the minimum number of samples for the tubers inadequately stored identification for frying. The minimum number of fried sticks for sampling and identification of inadequate storage of potato cv. Markies with 95% accuracy is 10.