Adding one banana can make your fruit smoothie lose its nutrients!
The 'nutritional trap' of a cup of smoothie: why do bananas make berries inactive?
Stir frozen blueberries, strawberries, yogurt, and bananas together to make a sweet and smooth fruit smoothie in less than a minute. But this seemingly healthy drink may be quietly losing key nutrients.
A joint study between the University of California, Davis and the University of Reading in the UK revealed that bananas contain highly active polyphenol oxidase (PPO), which rapidly destroys flavanols in berries such as blueberries and strawberries - plant compounds that are beneficial for the heart and brain and can improve vascular elasticity. As a result, their absorption rate decreases by 84%.
PPO is the "culprit" that causes fruit browning after cutting, and it is extremely active in milkshakes: it can degrade half of the flavanols in 10 minutes at room temperature, with a half-life of only 9.8 minutes. Even more surprisingly, even if bananas are not mixed with berries and consumed separately, the absorption of flavanols is still reduced by 37%. Because after bananas enter the stomach, PPO still retains 68% activity in the pH 4-5 gastric juice environment (which is its strongest activity range) and continues to degrade flavanols.
If you want to drink a nutritious milkshake without any discount, you can follow four suggestions:
Avoid high PPO ingredients, including apples, pears, and beetroot leaves, in addition to bananas;
Choose fruits with low PPO content, such as strawberries, blueberries, mangoes, etc;
Adding yogurt or citrus juice can inhibit PPO activity in an acidic environment;
Drink now to reduce the degradation time of flavanols.
The key to ingredient pairing lies in understanding the reactions of its ingredients. Only by selecting the right ingredients and making them scientifically can Guoxi be both delicious and nutritious.