Storing acidic foods in aluminum foil can lead to a chemical reaction between the acid and the aluminum, potentially causing the release of aluminum into the food. This can be harmful as excessive aluminum intake has been linked to neurological disorders, including Alzheimer's disease, although this link is still debated. Additionally, the foil may corrode or tear, allowing the food to come into direct contact with the foil, which can affect the taste and potentially contaminate the food. It's advisable to use acid-resistant containers or materials specifically designed for acidic foods to avoid these risks.