Researchers have found that the enzyme polyphenol oxidase (PPO) in certain fruits like bananas can reduce the absorption of heart-healthy flavanols, especially when combined with flavanol-rich ingredients like berries. The study suggests choosing ingredients with low PPO activity, such as pineapple or oranges, when making smoothies to optimize flavanol absorption.
Right? Insert a little bit of lemon juice and the polyphenol oxidase shouldn’t be a problem anymore. Also, banana wouldn’t be the only problem (concerning high polyphenol oxidase activity), would it? Cut up an apple and it turns brown before you can push all pieces into a juicer. Literally, I’ve had a couple R&D projects at the juice company I used to work for and we had this small Angel Juicer and by the time all apple pieces were in, the juice was brown (provided I didn’t spritz in lemon juice at the beginning).
Submerging apple slices in water with a bit of salt prevents browning. Doesn’t change the flavour like lemon as not much salt needed.
Hey, I know I’m like two days late to reply, but you probably wouldn’t need the salt even. The polyphenoloxidase reaction is what the name suggests, an oxidation. So it requires plenty of oxygen to run, which probably is inaccessible in water, I would assume.
I actually wasn’t quite sure anymore if I had that right and when googling it, I managed to find an entire diploma thesis on the polyphenoloxidase reaction, so for anyone that’s interested in it more deeply (sorry, it’s in German aside for the abstract, which is in English, too), have fun c:
My experience is from preparing sliced apples to eat later. Dip them in slightly salted water for less than a minute and they’ll hold for quite some time. No need to carry water in the container. The salt must help create an insulation membrane against oxidation. This is all practical experience and I haven’t seen research on it.