Univalle Researchers Developing Exotic Fruit Extractions to Add Value for Farmers

Tamarillo, also known as tree tomato or tomate de árbol, is a South American fruit rich in antioxidants — and now researchers at the Universidad del Valle (Univalle) are looking for a way to extract its antioxidants, as a value-added product for farmers.

Professor Laura Sofia Torres Valenzuela, at the Faculty of Engineering at Univalle, explained that the GIPAB  are beginning to explore useful Tamarillo (Solanum betaceum) extracts using “green” solvents.

"We will find out what bioactive compounds there are, from where and how to extract them," Professor Torres said.

Photo: An extract of the bioactive compounds of coffee. Credit: Professor Laura Torres

Natural Extracts

The average annual production of Tamarillo was over 150,000 tons in 2021, in Colombia, where they are consumed mainly in juices.

Also, in 2013, Tamarillo cultivation had exports to Europe and North America, with a value of more than 2.6 billion Colombian pesos (about $1million USD in 2013).

Tamarillo is also packed with bioactive compounds (chemicals that perform functions in the body that can promote good health), such as carotenoids, vitamin C (ascorbic acid), and various phenolic compounds. All of the above have antioxidant properties.

To extract these compounds and add value to the tree tomato chain or to the tree tomato agribusiness, Univalle researchers are applying a technique never used before in tree tomato: supramolecular solvents.

Professor Torres did her doctorate at the University of Córdoba in Spain about obtaining bioactive components from waste using supramolecular solvents, working with crops such as coffee.

Supramolecular solvents are a stable product of green chemistry—a system whose aim is to minimize waste, pollution and risks to health and the environment, following the 12 principles originally proposed by Anastas and Warner in 1988.

"Green solvents can be designed to maximize extraction," Professor Torres said, adding that they use ingredients generally known to be safe (GRAS).

Read more from the Food Engineering School: Colombian Engineers Create Nutritious Drink Based on Egg Protein

Professor Laura Sofia Torres Valenzuela, from the GIPAB research group, from the  Faculty of Engineering at Univalle.  

Towards Added Value

Professor Torres explained that more than 80% of farmers are small producers, profit margins are low and a large amount of organic waste is generated in the different stages of production and transformation.

"In all crops there is waste, but in the specific case of tree tomatoes, the peels and seeds are discarded,"  Professor Torres said, adding that when waste is not managed properly, it can have effects on water, soil , air and landscape, among other impacts.

Due to these factors, it is essential to look for new solutions.

"Our objective with the project is to create new possibilities of added value to the tree tomato, through the use of bioactive components in the residues (peel and seed)," said Alfredo Ayala Aponte, professor at the Food Engineering School of the Faculty of Engineering, principal investigator of the Tree Tomato project financed by Univalle.

In addition, the professor states that a novel process for the extraction of bioactive compounds that is friendly to the environment, high extraction capacity, versatile, low cost, such as supramolecular solvents, is used.

Professor Ayala explained that there are tree tomato fruits that are discarded in the post-harvest stage for not meeting some minimum quality standards, which are not marketed and are thrown away, increasing environmental pollution.

“These unsuitable fruits can be used for the extraction process of bioactive compounds and it would be an economic income alternative for the farmers of this fruit,” Professor Ayala said.

"These bioactive compounds obtained from tree tomatoes are useful to various industrial sectors such as food, cosmetic, pharmaceutical and nutraceutical companies," Professor Ayala said, adding that, in the food sector, the components extracted from Tamarillo can enhance properties functional properties of various foods beyond nutritional benefit. 

If you would like to contact the researchers or learn more about the projects, write to the Communications Office of the Faculty of Engineering: comunicaingenieria(at)correounivalle.edu.co.

Banner Photo: Tamarillo, also known Tree Tomato or Tomate de Árbol in a market. Credit: Natàlia Wilson