Westfalia Fruit is producing sustainable dyes with perseorangin, a pigment that makes up about 3% of an avocado stone.
Image provided by Westfalia Fruit
Avocado producer Westfalia Fruit is extracting a range of natural dyes from avocado stones as part of a goal to use 100% of the fruit.
Westfalia produces avocados to retail, food service, and wholesale customers in countries and regions worldwide, and makes up about 50% of the U.K. avocado market. In an innovation stemming from six years of research into valorizing avocado byproducts, the company says it can extract eight distinct shades of dye from avocado stones at its U.K. facility.
“By transforming what was once considered byproduct into a valuable resource, we’re creating sustainable solutions that benefit multiple industries,” explains Andrew Mitchell, Head of Group Innovation at Westfalia. “The ability to produce eight distinct natural shades while maintaining our commitment to use the entire fruit demonstrates the potential of innovative thinking in sustainable agriculture.”
Developing a sustainable alternative to chemical dyes
Westfalia worked with research group Efficiency Technologies to help it utilize every part of the avocado, leading to the new dye extraction process.
The idea started with a process to make use of avocados that would’ve been unsuitable for retail sale. Rather than waste that product, the company created a value-added processing facility in the U.K., where it would process the pulp from unsuitable avocados into products like guacamole, gelato, and smashed avocado. Initially, the stone and skin byproducts were sent to an anaerobic digester.
Westfalia saw greater potential in these byproducts than anaerobic digestion, though. “That’s where we started engaging with Efficiency Technologies to really valorize the avocado skins and stones,” says Matthew Churchill, Global Brand Manager at Westfalia. “There are a lot of valuable minerals, starches, and fibers in those parts of the avocado that can be extracted to unlock value even further, to strive toward our ultimate goal of zero waste.”
The dye extraction process is just one development to come from this approach. Westfalia worked with natural dye extraction specialist SAGES London to develop the process, in which the company isolates perseorangin, a natural pigment that constitutes about 3% of the avocado stone.
Westfalia's dye extraction process can produce eight distinct shades.Image provided by Westfalia Fruit“We take the seeds and mince them down into a pulp, add water and ethanol to extract the color, press the seed that’s been extracted to take the color out, then evaporate the ethanol back off,” explains Mitchell.
The company turns the resulting dye into a powder, extending shelf life and allowing for eight degrees of color ranging between light yellow to dark, reddish brown.
Not only are these dyes sustainable in their utilization of avocado byproducts, but they also reduce resource consumption in their production, compared to the potentially harsher production process of traditional chemical dyes. Says Mitchell, “The natural color is there; we don’t have to create anything. We just add the ethanol and remove it, with water in the process as well.”
Opportunities across industries
While currently in a proof-of-concept stage, the dyes have already had time in the spotlight at London Fashion Week in September 2024.
The dyes performance in terms of colorfastness, UV fastness, and wash fastness is comparable to synthetic dyes, reaching stage four on a scale of five across all three categories, Churchill explains. This lends the dyes well to fabric production, but that’s not their only potential use.The dyes perform comparably to traditional dyes in colorfastness, UV Fastness, and wash fastness.Image provided by Westfalia Fruit
Westfalia is also investigating the use of these dyes in the cosmetics industry for applications such as hair coloring and working with packaging leaders to explore potential uses.
“Natural dyes, natural pigments are quite rare and sought-after in industry. They really are what people are looking for as there’s a shift toward more sustainable dyes and pigments” says Churchill.
Supporting Westfalia’s total crop use strategy
The perseorangin pigment making up only 3% of the avocado’s stone is a prime example of Westfalia’s goal to use 100% of the avocado, bit by bit. The company’s strategy includes several other applications for the pulp, skin, and stones.
“It starts at the orchard level,” says Churchill. Like its value-added processing facility in the U.K., the company also has a facility in South Africa to process non-exportable or unsuitable fruit into avocado oil for food and cosmetics.
“At source country, the debris from that process will go back into the orchards as mulch for the avocado trees,” Churchill says. “The roots are quite well aerated, so that mulch is really beneficial to feed the trees.”
The total crop use strategy extends into the waste stream as well. Westfalia makes further use of its avocado stones by grinding them down to be used as an exfoliant scrub for cosmetics, acting as a sustainable alternative to microplastics.
The stones also have a high concentration of starch and fiber, making them ideal for artist-quality paper and even avocado packaging.Westfalia uses the starch and fiber in its avocado byproduct to produce artist-quality paper and packaging.Image provided by Westfalia Fruit
“We extract the fiber and starch and put it into pulp production for the punnets you put avocados in when they’re ripe and ready,” Mitchell says. “We can put a range of 10%, and even probably go up to 30 to 40% without compromising the punnets.”
After all this processing, the remaining material can be used in soap production, Mitchell says.
And to even further close the loop on the waste stream, Westfalia is considering a new system of miniature anaerobic digesters, which would turn leftover avocado material into energy.
“It cleans the water that you’ve used as well, takes anything you’ve used in processing, then gives you clean water and energy at the end,” explains Mitchell. He says the company that makes the systems is currently conducting trials in the U.K., and that “it could be an option to really make a whole closed circle of everything we produce.”
Plans to expand dye extraction capabilities
As Westfalia refines its dye extraction process in the U.K., the company is exploring options to expand it to its other facilities in Europe.
“Ultimately, we’d want to use it everywhere that we create a level of waste, making it worthwhile to process it, particularly once we’ve established the links into the customers who want to buy it,” explains Mitchell.
That’s all while the company continues to explore new ways to use the avocado byproducts overall.
“We’ve got these developments here, but something else might come along that we can use the skins and stones for, and develop that as well,” says Mitchell. “There’s a lot of opportunity in using this product, so we’re hoping that we can continue to improve it.”
Welcome to the inaugural Packaging World/ProFood World Innovations Report on liquid food packaging, drawn from nearly 300 PACK EXPO International booth visits (Chicago, Nov. 3–6, 2024). Our editors highlight the most groundbreaking equipment and materials—supported by video demos—that promise to transform how liquid foods are processed, packaged, and delivered.
Westfalia's dye extraction process can produce eight distinct shades.Image provided by Westfalia Fruit
