Few food products are completely stable; a fact that food scientists and technologists allow for during research and development. The acid level of a food is a good predictor of what microorganisms may grow and if we don’t control the acidity, the pH may change during storage. One way to control and maintain the pH of a food product is to use a buffer. Buffers are typically acids and bases which through some clever chemistry can either release more acid or absorb acid to maintain the pH. Luckily there are lots of natural buffers. Amino acids and proteins act as buffers, as do weak acids like citric acid and acetic acid.
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