The food by-products bioprocess wheel: a guidance tool for the food industry

Background: The reduction of food waste yields significant environmental and economic advantages, increasing the interest in the conversion of food by-products into functional ingredients. Biotechnologies, particularly enzymatic-assisted extraction (EAE) and fermentation-assisted extraction (FAE) have emerged as sustainable and cost-effective methods for upcycling food by-products. In the past few years, different processes have been explored using EAE and FAE. Scope and approach: In this article, we developed the food by-products bioprocess wheel (FBBW), a tool to guide academic researchers through the upcycling possibilities offered by biotechnological processes. The wheel also gives hints on the most promising scalable strategies for industry innovators. The FBBW considers several by-products resulting from the processing of the most common fruits, vegetables, crops, and cereals. FBBW is supplemented with analytical tables indicating the best processing conditions to upcycle vegetable, fruit, and cereal by-products. Findings and conclusions: The application of EAE and FAE technologies is still in its early stages. While EAE can be tailored to specific by-products and is generally more efficient, its cost depends on the use of commercial enzymes. Conversely, FAE is an economically viable promising strategy for repurposing agro-industrial by-products, its limitations are related to the readily available carbon sources to start the fermentation and in general to the sustained growth of fermenting microorganisms. The FBBW tool indicates the potential uses of both technologies depending on the by-product. Its use could be extended to pilot-plant scaled-up processes and facilitate the technological transfer from research laboratories to industrial settings.