Quantification of the waste stream from fresh tomato packinghouses and its fluctuations: implications for waste management planning

We studied the waste stream from packinghouses that process greenhouse tomatoes in one of the largest areas of protected cultivation in Italy in order to characterize this aspect of an important agroindustrial sector and to obtain preliminary data to support waste management planning. We studied 10 packinghouses by means of weekly interviews for 1 year, monitoring the total fresh tomato input, the total waste material generated by the selection and packaging activities, and the ratio of the two. We expressed the results as percentiles to better visualize the distribution of the data. All the studied characteristics varied among months and packinghouses. The amount of waste varied throughout the year, and its distribution appeared to be symmetrical around the median (18.3 Mg month-1), with interquartile values ranging from 15.6 to 20.1 Mg month-1. In contrast, within each month, the data for each packinghouse was asymmetrically distributed, and the cumulative range of the first two quartiles was generally narrower than that of the remaining two quartiles, emphasizing the presence of a few packinghouses that produced high amounts of waste. Totals of 34 780 and 2 195 Mg year-1 of tomatoes were collected and wastes were generated, respectively, by the 10 packinghouses. We used the resulting waste production ratio (6.3%) to estimate the regional amount of tomato packinghouse waste (10 823 Mg year-1). The year-round availability of treatable waste and its stability during much of the year confirms the relevance of this specific waste management sector. Nevertheless, a flexible approach for waste management planning will be required to handle fluctuations in the waste volume.