Abstract
Corylus avellana L. is one of the most cultivated species in the world. Mainly utilized with the purpose of obtaining food material, hazel trees cannot guarantee constant kernels productions given the threats related to pathogens and to adverse conditions, especially in a globalisation and global changes scenarios. This matter led us to consider the opportunity of using hazel tree in all its parts and for several purposes, due to its multifunctional characteristics. As a pioneer species, it is a precious plant useful for forest restoration purposes and for forest successions/wildlife facilitation. Its roots enter into symbiosis with truffles making this species exploitable for hazelnuts and truffles production. The precious elements contained in what is considered "waste" deriving from hazel crops (i.e., leaves, skins, shells, husks and pruning material), could be reused and valorised in the perspective of a circular economy that is opposed to a linear one. In particular, a list of several phenolic compounds detected in hazelnut shells has been reported in literature to prevent and delay many human diseases due to their antioxidant properties and to free radical scavenging activities, with implications potentially useful even in the fight against COVID-19. All this makes hazel crop by-products interesting to be valorised as a chemical compound source for human health, even more than a biomass fuel or for bio-char applications. The multiple possible uses of the hazel tree would lead to alternative productions than the only nut productions, avoiding significant economic losses, would decrease the cost of disposal of crops residues and would increase the sustainability of agro-ecosystems by reducing, among other things, the production of wastes and of greenhouse gases deriving from the usual burning of residues which often happens directly in fields.
Highlights
Last century has been featured by an economical growth model called “linear economy” [1]
The multiple possible uses of the hazel tree would lead to alternative productions than the only nut productions, avoiding significant economic losses, would decrease the cost of disposal of crops residues and would increase the sustainability of agro-ecosystems by reducing, among other things, the production of wastes and of greenhouse gases deriving from the usual burning of residues which often happens directly in fields
The unsustainability of the described model was widely demonstrated by Georgescu-Roegen [3]; alternatively, he suggested a Bioeconomy model, based on the principles of thermodynamics [3,4]
Summary
Last century has been featured by an economical growth model called “linear economy” [1] This has facilitated the use of products in a disposable way, creating a greater anthropic impact (i.e., much more waste, garbage and pollution, together with an increasingly use of energy and raw materials and soil uses change). The use of alternative strategies to avoid additional losses and produce several high value-added chemicals could minimize the volume of non-renewable materials used today, enough to greatly reduce greenhouse gas emissions and dependencies on nonsustainable resources Considering their available volume (practically low cost) locally and globally, associated with a rich, functional, structural, and chemical heterogeneity, all agro-industrial wastes should be considered for this purpose as well [11]. We took Italy as main example and as a case study for several reasons: it has a thousand-year historical use and cultivation of hazelnuts, it is considered the Nation that produces the highest quality nuts, it is the second largest producer of hazelnuts in the world, it has a wide Local Traditional cultural links with the Hazel and, Italy is one of the country in the world with the most important industries that utilizes hazelnuts, from the production to the final processing
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
