What influences buffet leftovers at event caterings? A German case study.

In recent years, a growing number of investigations have examined food waste in the food service sector, in which the catering of individual events received little attention. We aimed to contribute to fill this knowledge gap by presenting insights from a case study based on data from 239 event caterings. The case study presents findings about the influences of four variables, namely event type, season, event size, and menu prices, on buffet leftovers. We used a waste tracking system that allowed kitchen staff to quantify buffet leftovers for 4 years: from the beginning of 2014 until the end of 2017. Among the studied variables, the event size demonstrated the strongest influence on the generation of buffet leftovers in the case study. Buffet leftovers showed a trend of decreasing quantities relative to the number of guests for increasing event sizes. For instance, smaller events with less than 100 participants recorded the highest quantities of approximately 280 g of buffet leftovers per guest, and larger events of more than 500 participants recorded the lowest quantities of approximately 74 g per guest. In addition, we found that three food product groups-meat & poultry, finger food, and side dishes-caused approximately 54% of the overall quantity of buffet leftovers and approximately 65% of the corresponding monetary equivalents. Our findings emphasize that further research is necessary on food waste reduction strategies.