The Valorant project aims to transform horticultural waste (leaves, stems, pruning, …) into high added-value resources. In the interest of relevance and effectiveness, it might be worthwhile to examine the findings of previous European initiatives, such as the AgriWasteValue project.
What is the AgriWasteValue project?
The AgriWasteValue project (2018–2022) is an NWE Interreg project that preceded the current Valorant project and shares similar objectives. It aimed to valorize pruning residues from apple, pear, and grapevine cultivation into a circular economy across several countries in Northwestern Europe (the Netherlands, France, Switzerland, Belgium, and Germany).
The methodology was as follows: first, a quantification of these pruning residues was conducted. Next, the molecules of interest, as well as environmentally friendly extraction and processing procedures, were identified. Once they were selected, the high-value-added bioactive products were manufactured on a pilot scale to assess the viability of the processes.
These products were primarily intended for the cosmetic and nutraceutical sectors, and subsequently, the residues from these processes were utilized in the energy, chemical, and agricultural sectors.
Results and value chains
Apple presented a high potential of valorisation. Phloridzin is a phenolic compound naturally present in apples (peel, leaves, buds, fruit but also pruning residues). When oxidized, it can be used as a coloring agent in the nutraceutical sector. Its ability to regulate lipogenesis makes it an ideal ingredient in the cosmetics industry due to its slimming properties. The extraction and purification model has been validated and the residual biomass (particularly the cellulose and hemicellulose) contained enough sugars to undergo a fermentation process, leading to the production of biogas, heat, and fertilizer.
Regarding grapevines, resveratrol (a stilbene) was present in greater quantities, but the study concluded that the protocol applied to apple tree residues had to be adapted to vines.
On the other hand, the phenolic compounds of pear tree extracts (catechin, epicatechin, arbutin, chlorogenic acid) were too low to be valorized, and their purification was complex.
More investigations are needed!
Opportunities for the Valorant project
The Valorant project also aims, among other things, to recover value from biomass fluxes of apple, pear, and grape residues, although the considered residues are wider. The targeted applications are first in the food, nutraceutical, pharmaceutical, and cosmetics industries through the extraction of polyphenols, then after that the conversion of these secondary residues into proteins and finally the generation of bioenergy.
AgriWasteValue therefore shares similarities with the Valorant project in terms of its objectives and the crops considered, and can thus serve as a starting point and a source of information regarding quantities, harvesting techniques, storage, functional processes as well as those that are not relevant, and finally, area of improvement to be explored.
Valorising agricultural residues for
local and sustainable cosmetics and
nutraceuticals