From Banana Waste to Lactic Acid – A Sustainable Future

Bananas are one of the world main food crops, with more than 100 million tons bananas produced worldwide annually. This massive production generates enormous amounts of biowaste. Novel approaches are needed for handling waste from the production. In addition there is a need for innovative ways of utilising the earths resources to secure a sustainable future. The generated waste residues have a fairly high content of sugars mainly sucrose, fructose and glucose. In that way it makes up a potential good feedstock for production of value added products. Lactic acid bacteria (LAB) are naturally able to utilize these sugars present in banana waste and additionally LAB can be found in a wide variety of environments. Therefore we hypothesised that it would be possible to find LAB able to utilise the sugars, degrading the bio-waste and simultaneously produce lactic acid. With the use of LAB the problem with disposing of the bio-waste could be alleviated and lactic acid produced at the same time. Lactic acid is traditionally used in the food industry and is gaining ground in the production of biodegradable plastic leading to an increased demand for lactic acid. We have isolated and identified several suitable LAB with the ability to utilize bio-waste from banana cultivation as a feedstock for production of lactic acid. These LAB will enable a novel and efficient way of turning bio-waste with low economic value into value added products such as lactic acid. The strains have been characterized and selected for their ability to utilize the specific agricultural feedstock. Furthermore enzyme-treatment of the banana feedstock has been conducted, significantly increasing the concentration of free glucose. The best candidates capabilities were analysed by measuring the pH and the lactic acid content in growth cultures