New green way to take advantage of agricultural and food waste
Farming is how we produce food. No farming – no food, at least not until some lab-grown products become more widely available. However, both the farming and food industry produce a significant amount of waste, which could still be useful. Now scientists at the University of Adelaide have identified a new process for extracting health-promoting molecules found in agricultural and food waste.
Apples are great. They are full of vitamins and one apple per day keeps the doctor away. However, the apple industry produces a lot of waste. This is because apples are quick to rot, especially if they are damaged. Furthermore, people don’t buy ugly apples, even though they taste the same as the pretty ones. Finally, some apples are just not fit enough to be sold. 20 % of apple waste, however, is repurposed as animal feed – cows don’t care how they look. Meanwhile around 80 % are incinerated, sent to landfill or composted. Not great, having in mind how many useful compounds there are in apples.
Apple pomace is rich in compounds known for their antioxidant, antibacterial, anti-diabetes and anti-inflammatory properties. But how do you extract all that ‘goodness’? Well, you use solvents, because those health-promoting extracts found in apples have low solubility in water-based solutions. Although currently toxic chemical solvents are still being used, now scientists tried the use of greener solvents to collect those special compounds.
New solution, known as Deep Eutectic Solvents (DES), is inexpensive, green and even improves the quality of extracted compounds. Professor Vincent Bulone, one of the authors of the study, said: “Not only do DES provide a more environmentally friendly way to make better use of what would otherwise go to waste, but the collection method may provide a way to improve skincare, biopharmaceuticals and nutraceuticals.” For example, scientists found that in DES-pulled extracts the antioxidant activity was significantly higher than in samples obtained by conventional solvent extractions.
Not only that, but DES pulls out more of the useful compounds from the apple pomace. And because DES is inexpensive, it is simply more likely to be used. Why would the apple industry reject the offer to use more of their apples? This could provide a new revenue source as well as reduce food and agricultural waste.
Those health-promoting compounds could then be used in food or beauty products. And apples are just the beginning – similar green alternatives could be found for virtually all farms and food manufacturers. It is important now that DES becomes a commercial product and that the industry is ready to take advantage of it.
Source: University of Adelaide