Table 1.
A summary of selected studies reporting bioactive compounds and major components of food waste.
| Food Waste Type | Origin of Food Waste | Key Findings as Reported by Authors | References |
|---|---|---|---|
| Food service | Restaurant | Average analysis of restaurant waste (RW) from four studies showed range of values CP (15–23%), ash (3–6%), EE (17–24%) | [37] |
| RW was ground and had CP (22.0%), ash (12.6%), EE (23.9%) Afterwards, RW was mixed with other feedstuffs and then further processing took place |
[40] | ||
| RW was ground in a blade mill, mixed and homogenized, and heat processing took place (65–80 °C, 10–60 min) The nutritional composition of RW was CP (27.5%), Ca (0.42–1.7%), P (0.81–2.07%), EE (28.8%) |
[29] | ||
| RW underwent boiling Methionine, cysteine, lysine, P and Ca contents of the RW were quite similar between RW and a conventional diet Threonine and valine were higher in RW Salt content, PUFA, MUFA and SFA contents, and PUFA/SFA ratio were significantly higher in RW The n-6/n-3 fatty acid ratio was significantly lower in RW |
[44] | ||
| Hospitality sector | Food waste (FW) from Hotels was dried with the use of solar energy. The nutritional composition of the final product was Dry matter (92.74%), CP (25.62%), EE (21.57%), CF (6.75%) | Unpublished data | |
| FW contained kitchen and plate waste. FW were minced, pelleted, and dried FW contained CP (18–20%), ash (5–6%), salt content (2.0–2.5%), Ca (0.5–0.8%), P (0.3–0.8%), EE (24–26%) Lysine, methionine, threonine, and tryptophan contents were higher compared to corn, but lower in comparison with soybean meal Afterwards, FW were blended with a dry feedstock |
[16] | ||
| Restaurant and hotel | Leftover food was minced, heated and dried in hot air oven at 85 °C for 4 h CP (31.3%), ash (14.75%), EE (26.08%) |
[42] | |
| Food service and Households | Restaurant and apartment complex areas | FW was dried in a drum type dryer at 115 ± 2 °C CP (25%), salt content (3.28%), EE (17.3%) The majority of the essential amino acids, such as methionine and lysine, were considerably lower in quantity than that of a corn and soybean mix (60%:40% ratio) |
[41] |
| Commercial and residential locations | FW contained CP (27.6%), ash (14.56%), Ca (1.09–1.25%), P (0.16–0.30%), K (0.56–0.76%), Mg (0.1–0.2%), EE (9.12%), oleic acid (30.63% of EE), linoleic acid (25.5% of EE), linolenic acid (3.03% of EE), and had PUFA/SFA ratio (0.78), n-6/n-3 fatty acid ratio (7.94) | [28] | |
| Institutional | University dining hall | FW was dried in a forced-air oven at 60 °C for 72 h. Samples were ground and mixed FW contained CP (18.9%), ash (5.01%), Ca (0.04–0.46%), P (0.23–0.37%), EE (13.58%), arachidonic acid (0.20% of EE), linoleic acid (29.31% of EE), linolenic acid (3.82% of EE) |
[38] |
| Food services Institutional, Military, and Municipal | Hotel and restaurant etc. | Thiamine and niacin concentrations of cooked food waste were adequate to meet the nutritional requirements for swine, while the pantothenic acid concentration was deficient | [46] |
| Type unknown | Origin unknown | Leftover food was processed using fluidized bed dry method. Leftover food contained CP (22%) and EE (10.66%) | [39] |
Parameters are reported as mean and on a dry matter basis; Ca= calcium; CF = crude fiber; CP = crude protein; EE = ether extract; FW = food waste; MUFA = monounsaturated fatty acid; P =phosphorus; PUFA = polyunsaturated fatty acid; RW = restaurant waste SFA = saturated fatty acid.