I work in a restaurant where the chef saves time by parboiling potatoes and leaving them in the water overnight, then roasting them the following day. To stop the potatoes discolouring overnight, he puts a slice of brown bread in the water. Is this an old wives’ tale or does this really work? And does it have to be brown bread?
• When you slice a potato, an enzyme called polyphenol oxidase is released and catalyses a chemical reaction between polyphenols in the potato and oxygen from the air. This produces brown compounds in the potato called melanins, but can…
