Bananas are a very popular fruit in the UK but are often left out of the fruit salad as they quickly go brown and also make other fruits go the same way. Why is this and what is the new innovation Marks and Spencer have come up with?
First of all what makes bananas so special? They are grown in at least 107 countries and are ranked fourth among the world’s food crops in monetary value. Or put it another way, Americans consume more bananas than apples and oranges combined.
Bananas are amazingly good for you. They are rich in potassium which helps to maintain fluid levels in the body and regulate the movement of nutrients and waste in and out of cells. Potassium also helps keep the heart beating regularly and can reduce the effects of sodium on blood pressure.
What often puts people off bananas however is the browning that occurs so soon after peeling. Why does this browning happen?
The reason that bananas go brown so quickly is all due to an enzyme called polyphenol oxidase (PPO). This enzyme is released when the banana is cut, the enzyme converts chemicals called phenolic to quinones, and these eventually form the brown pigments that we see.
Bananas impact adversely on other fruits as they release a gas called ethene. This gas causes the ripening of other fruits by the conversion of starches to sugars
Marks and Spencer have discovered that if they spray bananas as soon as they are peeled with a mixture of citric acid and amino acid it will help keep them firm and yellow. The science behind it is that the enzyme doesn’t work well in acid. It’s similar to using lemon juice as a way of stopping the browning when we are preparing foods like bananas, apples and avocados at home. This development means that the food retailer will now be adding bananas to their fruit salads without the horrible brownness emerging.