Development of a weight-based technique for ‘packages labelled by count’ of agricultural products

Accurate weight-based packing of ‘packages labelled by count’ necessitate very low coefficients of variation of unit weight. For agricultural products with relatively high coefficient of variation, the usual weighing methods are therefore not suitable. In this paper, a method that supports the count-to-weight transform of pre-packed packages of products with wide variability of characteristics is presented. The developed innovative weighing method utilises a weighing procedure where the coefficient of variation of the product's unit weight is used in order to determine the critical package weight and to comply with the package nominal definitions. The method involves a weighing procedure of ‘packages labelled by count’ which is based on a mathematical model which reduces the variability in package size and eliminates the cases of under filling of packages. The method was validated experimentally. The results revealed that the variability of package size is high when counting manually. In contrast, by implementing the proposed method the standard deviation of the quantity in a package was reduced by 30%. Moreover, the number of packages with quantity less than the nominal was reduced to zero. In general, the developed method can be applied when the coefficients variation is high and the counting procedure is inaccurate and/or expensive.