Healthy coffee

A cup of coffee, representing Leeds researchers work

Impact is at the heart of all the food and nutrition research we undertake at Leeds. We aim to use our food science and nutrition knowledge and expertise to improve the quality of the food we eat and understand its impact on our health.

In this research, Professor Gary Williamson and his team of researchers have revealed new pathways of polyphenol absorption and metabolism in humans, including the effect of gut microflora on the bioavailability of these natural compounds found in coffee, having major impact on commerce.

This has provided the scientific evidence to support Nestlé’s post-launch marketing for its Green Blend coffee. The research supports Green Blend’s key positioning as a “functional” coffee with health benefits because it delivers high levels of antioxidants to the body.

The brand has estimated global sales of hundreds of millions of pounds per year.

Fresh (green) coffee beans contain high levels of chlorogenic acids, precursors of antioxidants that are known to reduce the risks of developing diabetes and cardiovascular disease. However, these acids degrade during high temperature roasting.

Nestlé launched a research programme to support their new pipeline product Green Blend, which contains a mix of green and roasted coffee, when Professor Williamson was working at the company.

Our research

The research aimed to investigate the bioavailability of antioxidant compounds in coffee and to study their metabolic pathways and functions in organisms.This research effort was extended when Professor Williamson moved to the University of Leeds to take up the position of Chair of Functional Foods.

Research by Williamson and co-workers in Leeds and at Nestlé, used high performance liquid chromatography to analyse for the first time chemical and enzymatic synthesis of coffee-derived metabolites.

Our results and impact

The research revealed that metabolism of chlorogenic acids involves several hydrolysis and conjugation reactions which produce phenolic derivatives. The research undertaken in Leeds was the first to successfully measure these phenolic conjugates in biological fluids.