Yesterday, I threw out four carrots that had gone from orange to black. It’s not the first produce I’ve put in the bin, nor will it be the last. Food waste is an enormous issue in today’s society. It’s estimated that 50% of food goes to waste before ever reaching our plates, with a significant proportion of this loss being caused by fungal infections like the one afflicting my carrots.
A new US company called StixFresh is working on a solution to help reduce food waste. With Prof Patrick Van Dijck (VIB-KULeuven) as their new CSO, a Belgian subsidiary and a 450K EUR grant from VLAIO, the company is perfecting their coating for fruit stickers based on antimicrobial plant extracts. By combatting fungal infections, these stickers are able to extend the shelf-life of fruits by several weeks, giving us time to enjoy our mangoes and pears before they go off.
Image: The different levels of spoilage for a mango with a StixFresh sticker (left) and a mango without a sticker (courtesy of StixFresh).
Tapping into plant immune systems
The StixFresh technology is based on naturally occurring antimicrobial compounds produced by plants to protect themselves against pathogens. Van Dijck has been studying these types of compounds for over a decade. In the past, plant metabolites have been chronically understudied, but Van Dijck says this is changing:
“We know that a lot of secondary plant metabolites have antimicrobial properties and, particularly with rising concern over antibiotic use, people have started taking this field very seriously. We are now analyzing the specific mechanisms that make these compounds effective antimicrobial agents.”
While the research is getting up-to-speed, industry has already been employing various secondary plant metabolites in their products for years. You may be surprised to find out that the menthol in your toothpaste is there not only for its minty-fresh aftertaste: it is actually a topical antibacterial agent, effective against several types of oral bacteria including Streptococci and Lactobacilli.
We want StixFresh to be a waste reduction company across the entire agricultural industry. From fruit to vegetables, dairy, meat and seafood; we are striving to position ourselves as global leaders. – Moody Soliman, StixFresh
In aquaculture, particularly in the shrimp industry, companies have started replacing traditional antibiotics with carvacrol and thymol; substances derived from oregano and thyme. It turns out these plant compounds are fantastic tools for targeting bacterial infections afflicting the shrimp, allowing the industry to reduce their reliance on antibiotics that give rise to antimicrobial resistant pathogens.
A sticky solution
The fruit industry is a natural market for a natural antimicrobial product, as a large proportion of fruit spoilage is caused by fungal and bacterial infections. This is exactly what StixFresh aims to do: reduce food waste by protecting fruit from pathogens. They’ve developed a formula that extends the shelf-life of the produce by several weeks by combatting fungal infections.
We need to be targeting the distributors and packers. Because that is where we could mitigate the problems down the supply chain and have a much larger impact on food waste. – Moody Soliman, StixFresh
The largest proportion of fruit is lost at the consumer level, when the fruit is ripe and vulnerable to pathogens. Most of the food waste generated by society takes place in our homes, restaurants and hospitals. This is why StixFresh are looking to target an earlier step of the supply chain: the packing houses. Moody Soliman, CEO of StixFresh, explains:
“In order to really capitalize on the potential of this technology we need to be targeting the distributors and packers. Because that is where we could mitigate the problems down the supply chain and have a much larger impact on food waste.
One of the reasons why this solution is so unique and special is that these stickers are actually the perfect fit for the industry. The vast majority of fruit already has a sticker on it, applied during the packing phase. By adding our solution to the surface of those stickers, the packers will see virtually no change in the overall process, meaning that the StixFresh solution can fit seamlessly inside the pre-existing supply chain.”
In Europe we are slowly transitioning away from plastic stickers, with companies increasingly using compostable stickers made of paper or other biodegradable materials. Would the StixFresh technology work with these eco-friendly stickers?
“Absolutely,” says Soliman “in fact we would prefer this; it aligns a lot better with our mission of reducing waste. Not just food waste, but all other waste associated with the industry as well.”
Finding the perfect formula for fruit
Though demand for their product is high, StixFresh are focusing on finetuning their formula before they hit the market. The company is in an interesting position: their sticker coating was created through trial and error. Although it has been tested, and works marvelously well, just how their formula functions is still unclear.
We initially developed this assay to find novel antimicrobial agents for human pathogens… now, we’re using the assay to decipher the mechanisms underlying the StixFresh technology. – Patrick Van Dijck, VIB-KU Leuven
This is where Van Dijck’s expertise comes in: together with his lab, Van Dijck has developed an assay that can be used to test the antimicrobial activity of different secondary plant metabolites. Over the next few months, the StixFresh R&D team will be using this assay to understand and perfect the StixFresh formulation. Van Dijck explained:
“We initially developed this assay to find novel antimicrobial agents for human pathogens. In the past, we’ve mainly worked on human fungal infections like Candida albicans, but we are also looking into other pathogens such as bacteria, biofilms and even nematodes. And now, we’re using the assay to decipher the mechanisms underlying the StixFresh technology.”
The potential uses for this assay are enormous and although the focus is currently on fruit, StixFresh are also keen on branching out in the future:
“Our vision is not just for a one-product sticker company for fruit,” Soliman told us. “We want StixFresh to be a waste reduction company across the entire agricultural industry. From fruit to vegetables, dairy, meat and seafood; we are striving to position ourselves as global leaders, with a range of natural and safe solutions.
