Fresh tomato packinghouses waste as high added-value biosource

In south-eastern Sicily, one of the greatest greenhouse tomato production areas in Italy, fresh tomato packinghouse waste stream was characterized for content of carotenoids (lycopene and β-carotene, biologically active compounds, highly valuable) and waste composition (vegetative matter, green fruits, turning fruits, red unmarketable fruits, and miscellaneous materials) in relation to their source (four packinghouses) and to the month in which they were produced (from December to July). Source and month both affected the characteristics of the wastes. The wastes were almost entirely putrescible, since miscellaneous materials were rarely observed. The highest proportion of red fruits (RF) and the highest lycopene and β-carotene contents were recorded in summer (836 kg Mg−1 and 57.5 and 8.3 g Mg−1, respectively, based on the average of the July and June values). Moreover, the proportion of RF was significantly correlated with the lycopene content (R = 0.839, P < 0.001), and this relation, when low incidence of RF in the total waste occurred, suggests the possibility of obtaining the same quantity of extractable lycopene by means of the selection of the carotenoid richest fraction that, consequently, minimizes the amount of waste involved in the extraction activities. These results suggest the potential for environmentally friendly and economically profitable waste management that integrates anaerobic or aerobic biotransformation processes with the extraction of carotenoids for an additional recovery of value from wastes.