Ah, marmite. The notorious dark brown, gloopy sludge (I’m hard-pushed to call it a food) is a byproduct of beer brewing. The yeast extract left over from brewing lager, bitter, and ale is mixed with vegetable and spice extracts, along with some other ingredients that are ‘trade secrets’. The manufacturing process sounds just as unappetising as the end product tastes.
The spread is behind one of the UK’s most divisive advertising campaigns – ‘Love it or hate it’. Polling agents YouGov ran a poll in 2011, asking 2,500 British adults whether they loved, hated, or had no opinion on marmite. The results were 33% for both love and hate, with 27% remaining neutral. That’s a pretty even split. Personally, I just can’t understand how anybody could willingly eat this vile excuse for a condiment. But clearly, people do. So what makes our palates so different?
Love it or hate it? (Image Credit: Helen Alford)
Taste and smell have long been evolutionary survival tactics. If something doesn’t taste right, we know to avoid it. Bitter tastes usually mean poison, while a sulphurous smell can be associated with something harbouring dangerous bacteria. The ‘survival’ role of these senses has declined as we have developed ways to keep food safe and the availability of food has grown. Even so, we still use these senses to judge food. If milk smells bad, we don’t put it in our tea. Evolution can explain the general aversion to bitter-tasting foods like grapefruit and broccoli, but what about more personal preferences?
Babies may inherit food preferences from their mothers. The flavours are transferred to the child from the mum through the amniotic fluid. One study found that babies whose mothers consumed carrots during the last stage of pregnancy were more likely to eat carrot-flavoured food compared to babies whose mothers did not eat carrots. The same principle could potentially be applied to other foods.
Another biological factor that can account for differing tastes is the amount of taste buds on an individual’s tongue. Taste buds detect the five tastes: sweet, sour, salty, butter and umami (savoury). “Supertasters” have more fungiform papillae – projections holding taste buds – and so taste things with much more intensity. They also have an increased sensitivity to bitterness. Research has shown supertasters have reduced preferences for foods including coffee, mushrooms, gin, tequila, green tea, and cabbage. Average tasters usually have a more accepting palate.
To try and understand why supertasters react negatively to certain foods, scientists are considering a gene named TAS2R38. The gene encodes a protein which is a bitter taste receptor. People who have a version of the gene that is very influential in tasting (as opposed to a non-tasting or subdued version) may be supertasters. Fussy eating could well be the results of genetic factors like this.
A person’s taste can evolve through the influence of various psychological factors. For example, association of a food with a feeling or emotion can affect the way the food is perceived in the future. If a person eats a food which makes them ill, chances are they won’t like that food anymore. The appeal of the food in terms of all 5 senses is diminished. In contrast, if a person associated a food with being exceptionally positive, they’re probably more likely to keep eating it.
Interestingly, recent studies have shown that people who enjoy bitter foods like gin may have psychopathic traits. One experiment showed that the ‘agreeableness’ of a person is negatively correlated with a liking of bitter foods.
Societal influences can also play a role in determining what people like and don’t like. As children, we naturally have a fear of trying new things. It’s possible that people whose parents encourage them to eat new foods regularly could grow up to be less fussy than those who stuck to a more restricted diet. Adults are expected to be less fussy than children, and so may be forced to consume foods they don’t like to ‘fit in’. Olives seem to be the prime example of this. Luckily, research shows that the more times you eat a food, the more you grow to like it.
Food preferences are down to the interaction of numerous factors. Gene variation, upbringing, number of taste buds, psychology, society, experience… Call me narrow minded but none of these factors could ever explain to me the love people have for marmite.