Coffee pulp, a by-product of coffee processing, could be nutritionally valuable and safe for use in food and nutraceuticals, according to a recently published study in the journal.
Researchers at the Universidad Autónoma de Madrid analysed the composition and safety of two coffee pulp derivatives: coffee pulp flour and a coffee pulp aqueous extract. Their findings revealed that both products are rich in dietary fibre, protein, and bioactive compounds, supporting their potential as functional food ingredients. The study adds to the body of work exploring coffee pulp’s potential, coinciding with several industry initiatives that are turning coffee waste into marketable food ingredients.
The research shows that coffee pulp flour, made by drying and milling the pulp, is a high-carbohydrate ingredient, with 76.7% of its composition made up of carbohydrates, 49.8% of which is dietary fibre.
The study reports that coffee pulp flour contains significantly more insoluble fibre than the aqueous extract, which is composed primarily of soluble fibre. Soluble fibre promotes the growth of beneficial gut bacteria, enhancing the microbiome and supporting overall digestive health. This makes the extract a promising candidate for use in beverages and dietary supplements focused on gut health.
Coffee pulp flour also provides a good source of plant-based protein, containing 12.9% protein compared to 7.5% in the extract. Flour has a more favourable balance of essential and non-essential amino acids, potentially making it a viable plant-based alternative protein source.
Both coffee pulp flour and extract are rich in bioactive compounds, including phenolic acids such as gallic acid and chlorogenic acid, known for their antioxidant properties. The extract showed higher concentrations of these compounds, with 597.6 mg/100 g of total phenolic compounds compared to 356.4 mg/100 g in the flour. This makes the extract a particularly potent ingredient for functional foods aimed at reducing oxidative stress and supporting metabolic health.
Chlorogenic acid, one of the most abundant phenolic compounds found in both the flour and extract, could play a role in regulating blood sugar levels and supporting cardiovascular health. These potential bioactive properties make coffee pulp derivatives interesting for use in food products that target health-conscious consumers, particularly those looking to improve heart health or manage blood glucose levels.
The study supports the growing recognition that coffee pulp, long considered a waste product, has significant nutritional value. The antioxidant properties of coffee pulp flour and the extract suggest that they could be incorporated into functional foods to help mitigate inflammation and oxidative stress.
To ensure that coffee pulp derivatives are safe for human consumption, the study conducted acute and sub-chronic toxicity tests in mice. The results showed no significant adverse effects or toxicity, confirming the safety of both the flour and the extract when consumed at the tested doses. The researchers found that coffee pulp flour and extract did not cause any harmful histopathological or biochemical changes in the animals.
The study also examined the levels of heavy metals in the flour and extract, including arsenic, cadmium, and lead. These metals, common contaminants in agricultural by-products, were found to be present in minimal quantities, all well below regulatory safety thresholds. This further strengthens the case for using coffee pulp as a food ingredient, providing confidence that it can be safely incorporated into products for human consumption.
The combination of strong nutritional benefits and verified safety makes coffee pulp a valuable candidate for food innovation, particularly for companies seeking to meet consumer demand for sustainable, functional food ingredients.
Several companies and projects are already turning coffee pulp into marketable products. One such example is the Zero Waste Coffee Project, initiated by Dr Hans-J. Langenbahn, head roaster at Happy Goat Coffee Company. His project focuses on turning the entire coffee cherry into usable products by building a network of coffee growers, roasters, and researchers with sustainable initiatives that can be a source of inspiration and motivation for other stakeholders with a similar ambition. Dr Langenbahn highlights that historically, the coffee industry has focused solely on the bean, treating the rest of the coffee cherry as waste. "Although there have been serious considerations about the use of by-products since the 1970s, it is only in recent years that marketable products and methods of better utilisation have been developed," he writes on his website.
Another promising initiative comes from the Netherlands-based startup PectCof, which produces Dutch Gum, an emulsifier and stabiliser made from coffee pulp. The company’s founders, Rudi Dieleman and his team, started developing the product in 2012 while at Wageningen University. Dutch Gum is used as a pectin replacement in products like plant-based ice cream, high-protein bars, and vitamin gummies. Unlike pectin derived from citrus fruits, Dutch Gum offers a unique combination of fibre and protein that stabilises emulsions and enhances flavour, making it particularly useful in dairy alternatives and other plant-based products.
In addition to large-scale commercial initiatives, smaller, community-based projects are also exploring the use of coffee pulp as a food ingredient. In Colombia, a project led by Briana Gómez Ramírez at the University of Antioquia is helping female coffee growers produce coffee pulp flour for local consumption. The project aims to address food security and improve nutrition in rural coffee-growing communities by transforming pulp into a low-cost, artisanal product. According to Gómez Ramírez, the flour works very well as an ingredient for arepas, bread, cookies, almojábanas, and cakes. It also adds value to beans, rice, soups, and stews.
