Unlocking value from food waste: A cross-regional meta-analysis of economic opportunities

Abstract

Numerous studies have evaluated the economic feasibility of transforming various categories of food waste into valuable products (or valorization) like bioenergy or biofertilizers. However, the cost-effectiveness of these transformations across regions remained uncertain. This systematic literature search on six common cost assessment methods on food waste valorization initially yielded 3964 studies. Using PRISMA guidelines, 50 studies were selected for the meta-analysis. The results suggested a moderate baseline effect ($g$ = −1.49, p-value = 0.04) using the Hedges $g$ algorithm, indicating statistically significant economic benefits of valorization than disposal. The Q statistic 11.8 with df = 5 and moderate heterogeneity (I² = 55 %) indicated modest publication bias. Leave-One-Out and Leave-Two-Out sensitivity analyses confirmed robustness of results despite including diverse valorization methods. An exception, techno-economic analysis (p-value = 0.8, I² = 0 %) indicated no heterogeneity between valorization and disposal methods. Hence, the cost viability varies with cross-regional economic and technical factors.