Sustainable Fats from Microbes & Food Waste Can Rival the Cost of Existing Lipids

A new analysis suggests that waste-fermented microbial lipid alternatives to fats like palm oil and animal fats can already compete with premium cocoa butter on cost.

The alternative fat space has been heating up rapidly over the last couple of years, though questions over this burgeoning sector’s cost-effectiveness have loomed large.

However, a new study published in Nature Communications Sustainability shows that if the technologies to produce these sustainable lipids can be scaled up, they can compete with incumbents on price.

Researchers from Luxembourg-based Cx Bio conducted a techno-economic assessment to demonstrate the feasibility of a fermentation-based approach that leverages microbes and food industry waste to produce fatty acids.

They explored two types of widely used fats: phospholipids (also called lecithin), which are used in products like chocolates and pastries; and triacylglycerols (also called triglycerides), which are oils and solid fats that give plant-based meat its richness and juiciness.

By their estimates, the minimum per kg price of fats produced via this process is $14.20 for the former and $10 for the latter. These reflect factors such as the cost of feedstocks, electricity, and capital expenses to build facilities, and are within the price range of premium ingredients like cocoa butter or egg- or soy-based phospholipids.

Under future scenarios where feedstocks become cheaper, microbial strains become more efficient, and renewable energy becomes more affordable, prices for phospholipids could fall to $6.10 per kg and $4.20 per triacylglycerols, making them competitive with a wider range of conventional fats.

Fermentation process for fats leaves behind useful co-products

The fermentation process analysed in the study involves breaking down organic products like food industry and agricultural sidestreams into biogas, which is converted into biomethane by removing CO2, water and impurities.

This can then take two routes. The biomethane can be used as a direct feedstock for microbes to produce phospholipids, or be synthesised into methanol, which then serves as a fermentation base for triacylglycerols.

Both approaches leave behind a co-product that can be used for other food applications. The biomethane route yields 2.6kg of protein-rich biomass per kg of lipid production, and the methanol route yields 0.9kg of lipid-rich biomass per kg.

“Fermentation promises a new approach that contributes to a circular economy by turning waste sidestreams into valuable food ingredients, and this study provides a robust roadmap for how this potential can be realised across Europe,” said Seren Kell, head of science and tech at the Good Food Institute Europe, which funded the study.

“Current production of fatty acids is unlikely to meet the global rising demand, while sourcing sustainable, scalable fats and oils that replicate the flavour and mouthfeel of conventional animal fats has long been a challenge for developing tastier plant-based meat that can appeal to a wider group of people,” she added.

Waste-to-lipid tech is widely scalable

The study’s focus is on a stream of ingredients designed to disrupt an industry with a dark stain on the planet. Animal fats come from an industry responsible for up to 20% of all global emissions and use up most of the world’s farmland and freshwater.

On the other hand, tropical plant-based fats like palm and coconut oil are linked to large-scale deforestation, wildfires, and threats to Indigenous populations and wildlife.

It has prompted the mainstream emergence of alternative fat startups like Savor, Clean Food Group, Checkerspot, Äio, and NoPalm Ingredients, among many others. These firms have closed a host of funding rounds over the last year, and are working with several food and personal care giants.

The authors of the new study suggest that the waste fermentation process for producing lipids is widely scalable, since Europe generates around 850 million tonnes of organic waste per year, which can produce thousands of tonnes of microbial fats.

A single production facility at the scale modelled would still represent less than 1% of the global demand for cocoa butter, indicating significant room to grow without displacing existing markets.

“No single technology will solve the challenges of food sustainability, but our findings suggest that waste-to-lipid biomanufacturing could become one important piece of the puzzle,” said Milena Ivanisevic, CX Bio co-founder and lead author of the study.

“If demonstrated at scale, it offers a way to transform underutilised organic waste into valuable food ingredients while working alongside existing food production systems to build a more circular economy,” she added.