The Zero Waste Coffee Project

My name is Dolores del Castillo. I am a Food Scientist.

Note: In our series “My name is…” we give a place to people who have or can have an impact in the world of coffee by-products, regardless of the specific field or application. Everybody presents him- or herself. If you believe that you are, or can be one of these “impact people”, or you know one of these people, please contact us (phone/WhatsApp: +1 613 262 7127, email:, LinkedIn: Dr. Hans-Jürgen Langenbahn)

Our first impact person is Dolores del Castillo, Spain.

Hello, my name is Dolores del Castillo. I am a research scientist in the Spanish National Research Council (CSIC), the largest public institution dedicated to research in Spain and the third largest in Europe. A primary focus of my research is on health aspects of coffee and coffee by-products. Coffee is fascinating to me as it is one of the world’s most popular natural sources of phytochemicals with health promoting properties of the human diet.

I received my PhD in Food Science and Technology at Complutense University of Madrid (UCM), Spain in 1999. Since 2011, I have been the Head of the Food Bioscience Group at the Institute of Food Science Research (CIAL), a research institute belonging to CSIC and the Autonomous University of Madrid (UAM)/Departamento de Bioactividad y Analisis de Alimentos, Grupo de Biociencia de Alimentos.

I was certified as a Functional Foods Scientist by Functional Food Centre Inc., USA, and received a formation in the Bioeconomy field by MINECO, Spain For 11 years I was a professor of the “Ingredients and Functional Foods Module”/Master in Food Quality and Safety of the University of the Basque Country (UPV/EHU), Spain (2007 – 2018), and am currently a professor of the “Master of Food Safety” organized by the Official College of Veterinarians of Madrid. In addition, I am a professor of the Food Sciences PhD Program, Faculty of Sciences at the Autonomous University of Madrid and member of the Chemoprotective Strategies against carcinogens of the diet at the Veterinary Faculty/Complutense University of Madrid. Last but not least, I am the Section Editor-in-Chief of Phytochemicals and Human Health, Nutrients Journal.

I started my research in coffee in 2001 under the supervision of Professors J.M. Ames and M. H. Gordon being a Marie Curie postdoctoral fellow at the School of Food Bioscience, The Reading University, UK. I have had the excellent opportunity to be part of a great scientific team involved in the COST Actions. Our focus was on the study of the role of the Maillard reaction in both food and medicine. The Maillard reaction is the main chemical event taking place during the thermal processing of the foods. It has a tremendous impact on the sensory quality, safety and health promoting properties of the coffee beverage, as well as among other very popular foods worldwide such as various baked products. The knowledge and skills I obtained during my postdoctoral training allowed me to complete my formation as PhD student at CSIC and I became an expert in this field.

Back at CSIC Spain, my research on coffee continued in collaboration with Dr. M.D. Mesa and Dr. F.J. Morales. We focused our efforts on the study of the effects of the green and roasted coffee beans components in diabetes and metabolic syndrome. The study was funded by the Federación Española del Café (FEC).

In 2010, we started research on the potential of the coffee-by products as a sustainable natural source of health-promoting compounds for reducing the risk of non-communicable chronic diseases. Initially, our attention was on by-products produced during roasting (coffee silverskin) and produced during the brewing of coffee (spent coffee grounds) which are abundant in developed countries. Later, we also studied other coffee by-products generated during the production of the green beans called cascara (pulp or husk), mucilage and parchment. Although only being produced in small amounts in the Canary Islands, Spain is the sole European country that produces coffee; thus for achieving a sustainable food chain we need to reduce the waste to zero. In addition, due to the nature and abundance of coffee by-products worldwide, coffee growing and production has a significant environmental impact which has to be managed in the right way.

To achieve this goal, we extended our collaboration with other scientists belonging to European Institutions, CSIC, Spanish Universities including UCM, UAM and Universidad Rey Juan Carlos (URJC), as well as the Universidad Autónoma de Querétaro, Mexico, and Harvard University in hopes of forming a multidisciplinary environment and to gain insight into the composition, structure and health promoting properties of coffee by-products. The results derived from all the investigations performed on coffee by-products are summarised as four PhD thesis, 25 scientific articles, four book chapters and three patents.

Here a few examples of the innovations proposed by our research team:

a) use of aqueous extract of coffee silverskin (Patent W2013/004873)

- as International Cosmetic Ingredient “Water and Coffea Arabica/Robusta  chaff extract to receive a soluble coffee silverskin”

- for the reduction of risk related to diabetes (P201431848)

- for the improvement of food quality

- as a natural source of melanoidins

- to be applied as natural colorant and beverage with health promoting properties

b) application of spent ground coffee in bakery products with improved nutritional properties (WO/2014/128320)

c) conversation of cascara into two different products avoiding the generation of new wastes: gluten free flour and ‘instant cascara.’

We are working in collaboration with coffee companies and non-governmental organizations on the transfer of the knowledge generated in the last 10 years to the farmers and industry for contributing to the sustainability of the coffee world and nutrition security. Currently, we are conducting new joint investigations with the research teams headed by Professors A. Farah and M.A Coimbra who are experts in the coffee field for further innovations on coffee by-products.

We need much more research in coffee in a multidisciplinary environment for achieving these goals. I am always glad to exchange ideas with other scientists working in this field and all involved in the coffee chain. We need to establish a common language to achieve a sustainable coffee chain. Coffee is much more than the black beverage we prepare daily from roasted beans. So many useful products (foods and others) can be produced from the different by-products generated in the travel from the plant to the cup. Let’s work together, scientists and producers for more benefits for all.