Nutritional Quality of Recycled Food Plate Waste in Diets Fed to Swine

Food waste samples were collected approximately bimonthly from five different New Jersey farms that feed food waste to pigs. All of these farms feed food waste collected from various institutions (restaurants, casinos, military bases, hospitals, and nursing homes) and often supplement with other byproduct feeds such as bakery, fish cannery, or vegetable processing wastes. A total of 63 samples were collected and analyzed for nutrient content in laboratories at the New Jersey Agricultural Experiment Station. Results from all five farms indicated that food plate wastes often have an acceptable nutritional profile. Crude protein averaged in excess of 20% and EE over 25%. Fiber levels were low and most minerals were borderline, if not adequate, for growing pigs. However, the low DM (27%) and the high variability of nutrients (CV often near or in excess of 100%) were significant limitations. For individual farms, DM percentage was always low, EE was high, and CP was variable. Mineral levels also varied from farm to farm. Calcium averaged 1.69% in food waste collected by Farm 1 and 0.36% in food waste collected by Farm 2. Several of the trace nutrients (copper, iron, zinc) were also variable. Zinc samples averaged 28 mg/kg on Farm 2 and 146 mg/kg on Farm 1. Zinc levels in food waste fed on Farms 2 through 5 were all inadequate when compared to NRC levels for growing pigs. Essential amino acids were, on average, equal to or above NRC levels required for growing pigs, except for lysine levels in food waste, which were below requirements on Farms 1 and 2. Results from this work have helped to develop a nutrient profile of the food waste currently fed to swine in the state of New Jersey and have been shared with individual producers. Food waste, although often of ample nutritional quality, is limited by its low DM and variable nutrient content, and should be monitored regularly and supplemented accordingly in practical feeding situations.