β-carotene acts as a pro-vitamin A or anti-cancer compound. Carrots contain the highest amount of β-carotene of common fruits and vegetables, but each year 25% of carrot production is lost in the U.S. during processing and storage, while, at the same time, the market demand increases. This article is a review of the most recent studies concerning β-carotene retention in carrots during processing and storage. Reducing the water activity by adding some aw lowering ingredients results in poor shelf-life. Drying or freezing gives better retention during storage than reducing the water activity, if the process is well controlled. Canning or freeze-drying were shown to be more effective. The trans form of β-carotene in carrots is replaced by the cis form during processing. β-Carotene can be extracted from carrots, but the half-life of free β-carotene is reduced to 2 d in the juice extract at room temperature. 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