Olive mill wastes: from wastes to resources

Abstract

Olive oil extraction has recently experienced a continuous increase due to its related beneficial properties. Consequently, large amounts of olive mill wastes (OMWs) derived from the trituration process are annually produced, causing serious environmental problems. The limited financial capabilities of olive mills make them usually unable to bear the high costs required for the disposal of their wastes. Alternatively, the valorization of OMWs within the framework of the so-called waste-to-resource concept and their recycling can represent a successful strategy for the implementation of circular economy model in the olive industry, which could have significant socioeconomic impacts on low-income Mediterranean countries. There is, however, no unique solution for OMWs valorization, due to the wide variety of the wastes’ composition and their seasonal production. In this review, the potential of OMWs for being reused and the recent technological advances in the field of OMWs valorization are assessed. Special focus is given to the analysis of the advantages and limitations of each technology and to reporting the most significant issues that still limiting its industrial scale-up. The information collected in this review shows that OMW could be effectively exploited in several sectors, including energy production and agriculture. OMWs potential seems, however, undervalued, and the implementation of sustainable valorization strategies in large-scale remains challenging. More efforts and policy actions, through collective actions, encouraging subsidies, and establishing public–private collaborations, are still needed to reconcile research progress with industrial practices and encourage the large-scale implementation of the waste-to-resource concept in the olive sector.

Polyphenol-Rich Extracts from Agroindustrial Waste and Byproducts: Results and Perspectives According to the Green Chemistry and Circular Economy

“…The valorization of agroindustrial wastes and byproducts is to convert these plant materials, mostly obtained downstream from agricultural production and the food industry, into high-value-added products (soil conditioners, compost, animal feed, cosmetic and food product ingredients, food packaging and building materials,...) or energy …”

“…The valorization of agroindustrial wastes and byproducts is to convert these plant materials, mostly obtained downstream from agricultural production and the food industry, into highvalue-added products (soil conditioners, compost, animal feed, cosmetic and food product ingredients, food packaging and building materials,...) or energy. 234 With this review, we wanted to contribute to the scientific literature by highlighting the application potential of olive oil and pomegranate processing waste and byproducts typical of the Mediterranean area. These materials represent a valuable source of molecules, e.g., polyphenols, endowed with multiple biological activities (antimicrobial, antioxidant, anti-inflammatory) that can be recovered through conventional and unconventional extraction techniques and used as active ingredients in the formulation of cosmetics, functional foods, dietary supplements, animal feeds, and innovative packaging materials.…”

Upgrading Strategies for Managing Nematode Pests on Profitable Crops

“…Over and above, several plant industries may be economically served by PPN control tactics. For instance, large-scale implementation of the waste-to-resource concept in the olive sector could exploit olive mill wastes for controlling serious pests such as PPNs [ 81 ]. Furthermore, it is imperative to characterize and grasp closely related factors that usually interact and affect such PPN management strategies.…”

The Effect of Varying Olive Mill Wastewater Concentrations on Soil Free-Living Nematode Communities and Lettuce Growth

“…However, repurposing OMW within the waste-to-resource paradigm and recycling it could contribute to a successful strategy for implementing the circular economy model. This approach has the potential to yield significant socioeconomic benefits, particularly for low-income Mediterranean countries [5].…”