The use of biomass in various sectors has evolved to offer sustainable alternatives to conventional fossil-based materials: by exploiting so-called biogenic feedstocks, industry can reduce its environmental impact and promote circularity. However, due to the complexity of supply chains and the available scale of raw materials, this is not always possible.
In such cases, a mass-balance approach can come to the rescue: a chain-of-custody model in which materials or products with a specific set of characteristics are mixed according to defined criteria with materials or products without that set of characteristics. Although the biogenic content is diluted and cannot be traced back to each individual product, the mass balance approach provides the means to calculate and declare that there was an equivalent amount of biogenic carbon used in production.
The mass balance approach, on the contrary, cannot be used to communicate the exact biogenic (carbon) content and therefore, the use of the term "biobased" is not appropriate.
It is preferable, therefore, to use the term "bio-attributed," which indicates that a biobased raw material use has been ''attributed'' using precisely the mass balance methodology (and is a clear distinction with materials in which the biobased content can be verified using the radiocarbon method).
Communication guidelines are key: there are special certification schemes in this regard that help differentiate between different models by ensuring traceability of raw materials, calculation and documentation procedures.
Vinavil has started its own path to sustainability certification, according to the goals included in the UN agency of some of its finished products using the mass balance approach.
ISCC Plus is aimed at all categories of industrial products unrelated to the world of biofuels and bioenergy, and the scope is extended to several products.
The sustainability of a product must be attested throughout the production chain, as well as the suppliers, giving the possibility of certifying the entire production of the product.