My toddler insists on having tomato ketchup on everything – he even requests it on his cereal. Why do kids love tomato ketchup so much?
• Hmm, I’ve never tried tomato ketchup on cereal, but it does go well with prawn crackers.
Your correspondent is right that children are particularly fond of tomato ketchup, and a leading manufacturer states that children are the main consumers of this product. To some extent the flavour of ketchup is designed to be attractive to small children because they detect sweetness more readily than other tastes. Commercially produced ketchup may be up to 30 per cent sugar, derived both from the natural sweetness of tomatoes and from added sugars, possibly in the form of high fructose corn syrup.
Advertisement
There is another reason why tomato ketchup is intensely attractive: its bright red colour. Old-World primates, including human beings, are unusual among mammals in having . In short, this enables us to see the colour red – an adaptation which would have been very useful for our ancestors in their search for ripe fruit and the russet flush of tender young leaves. Red foods are still attractive to us, and are perceived as being sweeter or richer. It is even possible to fool wine drinkers by adding red colouring to white wine, which they then perceive to have the fuller taste and “fruity nose” of red.
“Red foods are attractive to humans and are perceived as being sweeter or richer in flavour”
From 2000, Heinz tomato ketchup was made in other colours – green, pink, yellow and purple – but these were discontinued in 2006, so clearly the red colour is important.
As far as adult consumers are concerned, I believe they are also out there, but unwilling to admit a fondness for a product which is seen by food snobs as just too obvious in its appeal. Sweet and red – what’s not to like?
Christine Warman, Saltburn-by-the-Sea, North Yorkshire, UK
• Ketchup is popular with toddlers because of the high sugar and salt content. Animals, including humans, are hardwired to seek out sugar and salt, which are difficult to obtain in nature. For example, farmers put out salt licks for herbivores because their diet can have a dangerously low salt content. But manufacturers of the processed foods we eat exploit this propensity and put in high levels of sugar and salt.
About a quarter of the content of ketchup is sugar which, as we know, can contribute to obesity and diabetes, while the salt content is around 2.5 per cent. This means a modest serving contains about 0.4 grams of salt. The UK’s National Health Service recommends that 2 grams of salt a day is enough for children under 3 years old, 3 grams for 6-year-olds and 5 grams for 10-year-olds, so a dollop of ketchup on its own goes a long way towards these maximum amounts.
The proponents of ketchup point out that it contains an antioxidant called , a pigment responsible for the red colour in tomatoes and other fruits. While present in tomatoes it is concentrated in ketchup. Lycopene is said to protect people from cancer, including prostate cancer, though this condition, one suspects, is not a major worry for a toddler.
Terence Hollingworth, Blagnac, France