Tag: food

The Chemistry of an Onion

Chemistry Onion

The latest in the series of food chemistry graphics looks at the chemistry of onions – specifically, what causes their odour, and why chopping onions will make your eyes water. Interestingly, none of the compounds that cause these effects are present in the intact onion; rather, when the cell walls of the onion are damaged by chopping, an enzyme released produces a range of compounds as a defence mechanism, which act as irritants.

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