In a world where modern chemistry has allowed almost anything to be flavoured or coloured like almost anything else, you can stumble across some surprising substitutions. Take, for instance, the example of purple carrot juice.
Perhaps the purple carrot is not a vegetable you have much experience with, or ever thought about. When asked which variety was sweeter, orange or purple, one seller at my old farmer’s market’s answer was swift and unequivocal: “Orange.” At least with the varieties he was growing, the more common colour was the tastier. But purple carrots, whose hue comes from their heavy load of anthocyanins, have other talents.
Anthocyanins are present in blueberries, black rice, and even some autumn leaves. They operate as antioxidants, neutralising damaging oxygen species, which has led them to be darlings of the super-food industry. But that rich hue is another benefit – anthocynanins from various plant sources, like purple carrots, are approved by the EU and the UK to be used as food colourants.
Depending on their origins and specific chemistry, anthocyanins can turn food red, blue, or purple. These natural colourings can be used in foods that you would never connect with carrots or other sources of the molecules. Scientists have experimented with purple-carrot-tinged yoghurt and yoghurt coloured with extracts of the Peruvian berry B. boliviana. Even purple corn cobs have been tapped. Researchers found that they turn milk an attractive, vivid hue.
Another switcheroo is one you may have noticed: the tendency for some exotic fruit juices to be, on closer inspection of the ingredients label, mostly apple or grape juice. Consumer rights group wrote in 2012 that Tesco’s mango and passion fruit smoothie contained 47% apple juice, 23% mango puree and 4% passion fruit puree. These inexpensive juices make a handy, well-understood vehicle for more expensive flavours.
These days, juice labels have shifted in their descriptions. EU law now holds that “the product name shall be composed of a list of the fruits used, in descending order of the volume of the fruit juices or purées included, as indicated in the list of ingredients.” Though drinks with lychee, passion fruit, mango, and other exotics may still have substantial volumes of apple juice, labels must be more upfront, using names like “Apple and Mango Juice” instead. (Passion fruit rinds, however, have been tested out as a way to get more fibre into yoghurts that can be marketed as probiotic. Sometimes the exotic can hide in the commonplace for the sake of a marketing claim.)
As you eat your high-fibre yoghurt, sip orange juice, or perhaps even someday drink purple milk, keep your eyes open for these everyday glimpses of the chameleons in your food. Love them or avoid them, it’s hard not to be impressed by the ingenuity behind these stand-ins.