# From Grass to Protein: Assessing the Economic Viability of Mechanochemical-Assisted Extraction for Sustainable Food Production

## TL;DR

This paper explores using grasslands to produce edible protein and microbial lipids through a sustainable and economically viable process.

## Contribution

The study introduces a techno-economic framework for grass-based biorefineries and evaluates their economic viability at scale.

## Key findings

- Grass-based biorefineries can achieve high economic returns with median net present values of up to £1.21 billion.
- Protein production costs are competitive with plant-derived alternatives at £2.97–3.40 per kg.
- Logistical feasibility is demonstrated for sourcing silage across UK grasslands at low delivered costs.

## Abstract

Grasslands represent one of the world’s largest
yet most
underexploited renewable biomass resources. Here, we present a techno-economic
framework for transforming grass silage into edible protein and microbial
lipids through mechanochemical and biocatalytic processing. Two biorefinery
configurations were evaluated using stochastic and spatial modeling:
a baseline system producing protein and biogas (Scenario 1) and an
integrated design incorporating lipid fermentation (Scenario 2). Both
achieve strong economic performance at industrial scale, with median
net present values (NPVs) of £528 million and £1.21 billion,
respectively, and protein production costs of £2.97–3.40
kg–1comparable to plant-derived alternatives.
Sensitivity analysis reveals that protein extraction efficiency and
product price dominate profitability, while scale and coproduct valorisation
drive the largest gains in expected NPV. Spatial simulations show
that sourcing 33,333 t y–1 of wet silage (25% DM)
is logistically feasible across UK grasslands at delivered costs of
£51–58 t–1, enabling decentralised,
regionally integrated deployment. Together, these results establish
grass-based biorefineries as a scalable and economically credible
route to sustainable protein production, bridging agricultural residues
and food technology. The study provides quantitative guidance on how
process yield, market development, and spatial logistics can be co-optimized
to accelerate the emergence of a circular, pasture-driven bioeconomy.