From vegetables, fruits and legumes, it is possible to extract innovations from nature: organic dyes, which can replace synthetic (artificial) versions and which already have high applicability in various industries: from textile to food. But a natural dye can be unstable depending on the light and temperature conditions of the environment in which it is applied, making it a challenge to stabilize its characteristics – processes that often require a greater expenditure of energy and a greater use of organic resources, which which causes negative impacts on the environment.
To solve this problem, researchers from the Faculty of Applied Sciences (FCA) and the Faculty of Food Engineering (FEA), both from Unicamp, developed a faster and more natural alternative for creating dyes from grape skins, which contain the anthocyanin component, responsible for the fruit's color.
Maurício Ariel Rostagno, professor at FCA and one of the inventors of the technology, highlights that the proposal is 100% ecological, as the resin applied in purification can be reused for eight different cycles without losing its efficiency.
“We have a proposal that is much more sustainable for the environment and healthier for people. After all, synthetic dyes cause great concern due to allergy risks and health impacts. And companies are starting to be charged for this, which leads us to have a large market demand. We look for more efficient and greener ways to purify these compounds, with less environmental impact and lower cost”, he comments.
The new technology, which had a patent application filed with the National Institute of Industrial Property (INPI) with a strategy of Inova Unicamp Innovation Agency, is a fast process that does not use highly volatile organic solvents and presents much more stable results than pigments obtained with extraction using ethanol or water.
Furthermore, the process does not require sophisticated equipment or specialized labor.
“An important point of this process is stability. We are able to have a high yield and high purity, at the same time as we increase the stability of the compounds, obtaining greater stability than that of conventional processes. We have a recovery of over 90% of the solvents.”
industry challenges
The use of natural dyes is an ancient practice of humanity. However, its use lost strength with the advancement of synthetic dyes, which offered more stable colors than natural products.
But the pigmentation of foods and fabrics with artificial dyes requires high energy expenditure and the application of organic solvents and chemical stabilizers with high toxicity and high levels of water contamination. The solvents used also do not promote high extraction yield or selectivity in the process, which requires the application of new subsequent purification steps.
In the textile industry alone, around 90% of water consumption occurs in the dyeing and finishing process, making this process more expensive and producing excess waste. Furthermore, they are products that arise from the extraction of oil, a non-renewable energy source.
Vivid and ecological colors
With the new process, natural dyes reach a purity of 90%, guaranteeing a bright and more stable color. Solvents also allow the use of dyes at high temperatures, which expands the possibilities for their use in industry.
Maurício also highlights as a benefit of the new technology the use of fruit waste that is often discarded in the agricultural sector and which can now be used as raw material for new products, which also contributes to better use of natural resources.
“Recovering these compounds, which would be discarded as fertilizer, generates much more added value to grape production. In addition to all the recycling of absorbents that remains during the process developed at Unicamp”, he explains.
In addition to Rostagno, Leonardo Mendes de Souza Mesquita, Juliane Viganó, Letícia Sanches Contieri and Vitor Lacerda Sanches participated in the development of the technology.
Research-Market Connection
For the new grape skin-based dye to reach the market and be produced on a commercial scale, licensing of the technology is necessary. Inova Unicamp is responsible at the University for receiving contacts and carrying out negotiations in this regard.
Companies interested in having access to Unicamp technology for the development of products using innovative processes can contact Inova at Research and Market Connection form.
Article originally published on the Inova Unicamp Innovation Agency website.
