Sugarcane is a very important food crop, also used for biofuels and the chemical industry. One of the problems with sugarcane farming is all the waste it produces – it really is one of the dirtier kinds of crop farming. However, scientists from the University of York, and Indian and UK companies have set out to make use of or by-products of the sugarcane industry and found a way to use waste as a valuable chemical used in food, medicines and cosmetics.
Sugarcane is one of the most common food crops in parts of the world with warmer climates. For example, India is the world’s second largest producer of sugar right after Brazil. Sugar is an important part of our lives and sugarcane farming provides jobs for remote communities. However, this industry produces a lot of bagasse – a biomass, which at the moment is being burnt as fuel to power sugar factories.
Burning some waste to produce power may seem like a good way to repurpose some of the waste. However, the sugar industry doesn’t use all the bagasse available and the process of burning it for energy is extremely inefficient. However, now scientists discovered a way to use up more of the bagasse and do it more efficiently.
Scientists found that pre-treating the bagasse by warming it and adding a dilute alkaline makes it easier to process and handle. Researchers found that such a pre-treatment breaks down the fibrous structure of bagasse and makes it easier for chemicals to interact with this waste product. Scientists also created an enzyme cocktail to break down bagasse even further. Then a fungus called Aspergillus can be added to the mixture to consume sugar and emit citric acid. This process transforms bagasse from an industrial chemical into citric acid, which has many different established applications.
Dr Deborah Rathbone, one of the authors of the study, said: “We have shown in this project that we can use the sugars from this waste product to produce citric acid. This versatile chemical has applications in a number of different sectors, such as food, pharmaceutical, cosmetics and so on, because it’s generally regarded as safe and a material that can be eaten.”
Scientists already see the potential further steps – they want to scale up and commercialise the process. As the sugar industry is very big, they should lack clients who would like to adopt this process. There is a huge economic potential of bagasse recycling and it is one of the factors, which could determine that the interest in turning waste into something usable will be huge.
Source: University of York