Tuesday 21st November
Taste and Flavour
It’s a marginally shorter post this week, as Monday was spent giving, and listening to, group presentations as part of our ‘Food and Drink: the relationship to people and place’ module.
On Tuesday, we investigated taste and flavour, beginning with a session led by Laurent Vernet, Head of Marketing at Quality Meat Scotland (QMS). Laurent is also one of the few professional meat tasters in the world, and said that he can tell whether an animal has been put under stress before it has been killed by tasting a piece of meat. At QMS, he works to protect Scotch Beef and Scotch Lamb, both with PGI (Protected Geographical Indication) status, where they are trying to find a balance between preserving traditions and giving the consumer what they want. Increasing interest in buying these products, particularly amongst young people and especially in the case of lamb, could be incredibly important ahead of Brexit, when we might need to rely more on British produce.
Laurent gave us a brief history of meat-eating in Scotland, including not just animals but also turnips, which arrived in Scotland from the Middle East in 1747. In a time when fresh meat did not last long due to a lack of refrigeration, the root vegetables became a popular staple, and could feed animals during the winter when there was not enough forage. Meat production in Scotland began during the Napoleonic wars, due to the request of British food by the navy, creating a need for Scottish animals to be sent to London for slaughter, ahead of being sent out to sea. Laurent also spoke of black pudding being created out of necessity, from blood collected from the animals and mixed with suet, oatmeal and onion, to be eaten during the winter months.
For Laurent, the enjoyment of food is more interesting than the science, which he said he finds “unromantic and unpassionate”. Food is part of our identity, and people can be defined as much by what they don’t eat as by what they do. He uses this to shape his marketing campaigns for QMS to try to engage with consumers. There has been an increase in interest surrounding the ethics of our meat, and this is another factor that QMS need to address, particularly amongst millennials, who Laurent said are putting ethics before the eating experience in regards to where they’d spend their money. Using some of those key, but vague words like ‘traditional’, ‘natural’ and ‘artisan’ can tap in to this audience, who also prefer slightly blander meats in comparison to an older generation fond of a stronger meat flavour.
We began speaking about how to improve awareness of taste. Laurent initially trained himself to detect flavours with white tea, and still uses little unmarked jars of herbs and spices to test his sense of smell. With this he can build up a library of flavours that he can pick out when tasting different meats. He gave us a sample of pine jam and asked us to shout out our first thought about it, which ranged from “sweet” to “disinfectant”, showing how our perceptions of, and associations with, the same product can vary hugely. This led nicely on to our afternoon session on a more scientific approach to taste and flavour.
Why do we taste? As omnivores, it is important to distinguish between flavours, to work out what is edible and inedible, and to make a choice between all those edible foods. It is commonly believed that there are five ‘tastes’: bitter, sweet, sour, salty and umami. Bitter is the warning taste for anything that might be poisonous and so it is a taste we are programmed not to like, however we have adapted over time to enjoy many bitter tastes, whether in green vegetables or alcoholic drinks, and have made some bitter foods more palatable through cooking. Humans have an innate love of all thing sweet, deriving from our need as hunter-gatherers to find fruits and high-calorie foods. However, this longing for sweetness, and the fact that we can buy large quantities of sugar easily and cheaply, is now leading to increased rates of obesity and diabetes. Sour tastes signify acids, but they are also flavours we enjoy, in fruits, which we need for their vitamin C, and in fermented foods like sauerkraut.
Salt is another taste we seek out for health benefits, as we need a certain amount of salt, but not too much. Finally, umami, the most recently discovered taste, denotes savouriness and can be found in foods such as tomatoes, mushrooms, cheese and meat. Currently, other possible ‘tastes’ are being researched, for example kokumi (heartiness), starchiness, and fattiness.
We have thousands of taste buds, with receptors for different compounds. Amongst those, we have 3 sweet receptors and 30 bitter receptors. To test these, we began a series of experiments, starting with the blue tongue test. For this, we applied blue food colouring to our tongues, stuck on one of those reinforcement rings that you may well have had in your stationery set at school, and counted the larger fungiform papillae (the bumps on your tongue containing taste buds). If there are fewer than 15, you are a non-taster (which doesn’t mean you can’t taste, just that you are less receptive to flavour), 15-35 means you are an average taster, and more than 35 means you are a supertaster. Although a fun experiment, which provided giggles and a lot of amusing photos, it was actually pretty difficult to accurately count the papillae, so many of us didn’t have a clear result for this test.
The following experiments were easier to get results from, as they involved tasting some paper strips impregnated with various chemicals. The first was phenylthiocarbamide (PTC). As we all put the strips on our tongues, some didn’t flinch, saying they couldn’t taste anything, and a few of us, me included, found the chemical horrifically bitter and immediately took the strip out. We tried the same with the next strip, containing thiourea, which had similar results, with a few more of us finding the taste quite unpleasant. We were told that those of us that found these first two tastes unbearable were classed as supertasters, thought to be around 20% of the population. This is due to genetics, with the TAS2R38 gene being dominant in those who are supertasters, which makes them more sensitive to bitter compounds. The final strip we tasted was impregnated with sodium benzoate, which is sometimes used as a preservative. Between us, some tasted sweetness, others saltiness, others bitterness and some again tasted nothing. Judging from how differently we reacted to these compounds, it’s quite mind-blowing to think how everyone’s sense of taste could be so varied. No wonder we all like different foods if we experience them so distinctly.
Finally, we looked at smell and flavour, as 85% of what we perceive as flavour is believed to be olfactory (linked to smell). We tested our retronasal smell by pinching our noses and eating a piece of apple. We then let go of our noses to reveal the full flavour of the fruit, including a huge hit of cinnamon, which had been liberally sprinkled on by our lecturer. This goes to show how what we believe to be flavour is not just down to taste, but mainly due to smell (and the millions of olfactory receptors we possess). Sound, touch and the look of the food are also incredibly important to our perception of flavour, and enjoyment of the food.
Although I have now been technically classed as a supertaster, it’s clear that there is a lot more to taste and flavour than simply whether you are particularly sensitive to bitter compounds. It’s a lot more personal than that. It might mean that I struggle with hoppy beers, coriander, green tea and certain coffees, but I enjoy brassicas, olives, spicy foods, and gin and tonic. Even though many of these I’ve had to teach myself to like, I believe there are far too many exciting foods out there to be held back by genetics!