The science behind the flavours of Christmas - sprouts and all
Release Date 20 December 2011
If the thought of eating Brussels sprouts at Christmas turns your stomach, try this for an excuse: it's in your genes.
Dr Lisa Methven, a lecturer in food and nutritional sciences from the Department of Food and Nutritional Sciences, University of Reading, said the reason why some people can't stand sprouts is an over-sensitivity of taste buds on the tongue.
Her insight into ‘The Science behind your Christmas Dinner' was made as she presented a lecture to members of the Society of Chemical Industry at an event at UCL on December 7.
Dr Methven said the more taste buds on someone's tongue, the more likely they will taste sprouts as bitter.
"These people have a heightened perception of the bitter taste - we call them 'supertasters' - and this is due to their genetic make-up," she said.
"They experience the bitter taste up to 60 times higher than someone with an average number of taste buds."
However, Dr Methven pointed out that an unpalatable taste was not an excuse for children to spurn green vegetables.
"Just because you don't like something, doesn't mean you can't train yourself to like it," she said.
"If you keep on trying, you probably will like it in the end."
As part of her presentation, Dr Methven took her audience through a complete three-course Christmas dinner, explaining the chemical reactions that make our favourite festive food taste the way it does, and why certain things are good for us.
For example:
- Starters: Whether it's smoked salmon, tomato soup or a glass of sherry, Christmas dinner often begins with an appetiser, to get your guests' appetites turned on before the main feasting begins. This works by sending the first sensory signals to the appetite centre in the brain. Aroma compounds can start to induce saliva flow, the release of gastric acid and an increase in hormone levels. Appetite and satiety are highly influenced by release of hormones: Neuropeptide Y and Ghrelin stimulate appetite, whilst Insulin, Leptin, Cholecystokinin and Peptide YY depress it.
- Turkey: What makes roast meat, such as turkey or goose, taste so distinctive? It's all down to the roasting process, which enables sugars to react with amino acids in the meat creating lots of ‘roasted' flavour compounds, through a reaction known as the "Maillard reaction". But what about the taste on the tongue, not just the aroma compounds? The meat contains ribonucleotides that give the characteristic savoury or umami taste.
- Nut roast: For the vegetarian nut roast, its amino acids and sugars in the vegetables such as onion and carrots, that also form roasted flavours through similar Maillard reactions. In the nut roast the savoury taste can be created through the use of dried porcini mushrooms and sauces like soy sauce or Worcester sauce, again all rich in umami taste compounds.
- Cranberry sauce can make you think faster and improve your health. Cranberries can protect brain cells from damage and the tartness in the fruit can enhance your memory, balance and co-ordination. They also provide necessary antioxidants which keep you healthy and fit.
- Sausages: The distinctive smell of Christmas food, such as sausages wrapped in bacon, are part of a gigantic catalogue of 10,000 aromas in your brain that the average person can remember.
- Sprouts: We have 25 types of bitter receptors on our tongue and one affects how we rate green veg, such as sprouts, broccoli and kale.
- Veg: Young children on average need to see new food 15 times before they will taste it - a reminder to parents that perseverance is needed to get their children to eat fruit and veg.
- Christmas pudding: Christmas puddings were first developed as a method of preserving meat through the winter, and later incorporated the fruits and spices we use today.
ENDS
For more information, contact Pete Castle at the University of Reading press office on 0118 378 7391 or p.castle@reading.ac.uk.
Notes for Editors
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