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The alpha-keto acids produced by aminotransferase activity are relatively unstable and do not accumulate in cheese but are rather degraded via a range of pathways. Taking tyrosine as an example, its alpha-keto acid (p-hydroxy phenylpyruvate) can be degraded by 2-hydroxyacid dehydrogenases to the corresponding hydroxy acid (p-hydroxy phenyl lactate). Other pathways of degradation of alpha-keto acids include decarboxylations and chemical degradations forming other volatile flavour compounds, which will be discussed in future posts.![](https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEig8MrCMcweupOoDhxjLg8JBwQe_6qj3WZQkCcfOsbJPAxmO0NkQQt61-nKr4C5HHyhXVCn47R-DCyQPfDGp9SJxCEFjS3vqKUpSdtc-4z11iiaFxQ4A8kKNXFEnblXgWSUG6dNGgT90KY/s320/Keto2.png)
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