The unlikely neutron science behind your Christmas menu

They say that cooking a great Christmas dinner is an art form, but there is also a surprising amount of science that happens in the manufacture of the ingredients that go into your festive treats. Food researchers have used ISIS Neutron and Muon Source (ISIS) to develop and perfect these ingredients to ensure that, in the future, our meals are not only tastier but also more sustainable.

Synthetic turkey sandwiches anyone?

Whether it be from a moral objection to killing animals, or an awareness of the environmental impact of animal rearing and meat production, more and more of us are looking for ways to eat less meat. While only around two per cent of us are vegetarian, casual vegetarianism, or ‘flexitarianism’, is on the rise and more people are substituting their meat and two veg for veg and more veg, or vegetable protein-derived meat substitute and two veg.

However, if there is one time of the year that a lump of soya protein won’t cut the mustard for most, it is at Christmas and the venerable roast turkey meal. But what if there was a way you could have your Christmas turkey without having to harm an actual turkey? If scientists could find a way to engineer non-animal proteins into fibrous bundles that have similar characteristics to meat, we might be able to design ‘synthetic meats’ that have all up-sides of meat without any of the environmental or ethical downsides.

Scientists from the University of Reading have been working at the ISIS Neutron and Muon Source to develop one possible method of achieving this known as ‘electrospinning’. This method uses electric fields to produce long, continuous fibres and then spin them together to simulate the muscle fibres present in real meat.

In their experiments, the team investigated the use of whey protein, which is derived from milk, as a potential building block for synthetic meats. They found that, by including a polymer called Polyethylene oxide (PEO), they could create uniform fibres much like those seen in ‘real’ meat.

They hope that, with further improvements in the spinning process, we could soon be looking at a future method of producing artificial meat that would allow us to gobble our turkey without taking the gobble gobble out of the turkey.

What makes a Christmas treat taste like a treat?

Have you ever wondered what makes mince pies taste sweet? The simple answer is that they contain sugar, but it’s not as simple as a question of the amount of sugar they contain, but rather the type of sugar.

Food manufacturers put a lot of research into improving the taste of their products, but they rarely consider how we perceive taste in the first place, or ask the question: what makes us perceive some things as being sweeter than others?

Although the mechanics of taste are very complicated, we do know that taste is sensed by chemical receptors on our tongue. In the case of sweetness, sugar molecules bind to these receptors, sending instructions to the brain that triggers the release of signals that tell us that something is sweet. The number of sugar molecules and how effectively they bond to our taste receptors affects how sweet they taste.

Scientists from Universita di Roma, Italy, and the University of Oxford used the SANDALS diffractometer at ISIS Neutron and Muon Source to investigate sugar molecules to see what affects our perception of sweetness. They looked at the sugars glucose and mannose because, although they have a similar molecular structures, glucose is perceived as being the sweetest.

The team found that it was the strength of the hydrogen bonds within each sugar molecule that determines its sweetness. They found that glucose is perceived as the sweetest because it has shorter hydrogen bonds than mannose, which is perceived as being sweet but with a bitter after taste.

It is hoped that the research will help to develop new artificial sweeteners that are perceived as sweeter than normal sweeteners – meaning that less would be needed in food manufacture.

Seeking a creamy Christmas miracle

It can be difficult catering for a large family at Christmas – each member of which may have different tastes. Some might like to embellish their Christmas pudding with lashings of brandy butter, while others will prefer a flood of double cream, or perhaps even a dollop of ice cream. But what if, in the midst of the festive excitement, you leave the ice cream out of the freezer and, a few hours later, you return from your (possibly synthetic) turkey-induced slumber to find it has melted?

The optimist might return it to the freezer in the hope that it will refreeze and be resurrected to become the creamy-textured treat it was before it succumbed to ravages of the kitchen’s heat. Unfortunately, more likely than not, they will find that the ice cream has become rock-hard and large ice crystals have turned the texture from silky smooth to unpleasantly grainy. But why does this happen, and can anything be done to make melted ice cream salvageable?

Scientists have used ISIS to investigate how varying the ratios of ingredients in dairy products can have an impact on their structure and stability during this texture-ruining process, which is known as crystallisation. By studying crystallisation of ice cream in real time through different temperature cycles, we can learn how melting and refreezing changes the texture of ice cream. They found that by varying the product’s ingredients, we might be able minimise the impact of crystallisation and preserve its taste and texture – meaning there might be hope that, one day, that sad vanilla puddle might be returned to some semblance of its former creamy glory.

What makes chocolate so luxurious?

So you’ve stuffed yourself with synthetic turkey, mince pies and Christmas pudding, and now it’s time to crash out on the sofa to watch Die Hard for the 50th time. You are completely stuffed, but then you spot the bowl of Christmas chocolates and… well, it would be rude not to wouldn’t it!

But have you ever stopped to wonder what makes one chocolate treat so silky and luxurious when another might be hard and a bit grainy?

The secret is in something called the ‘mouthfeel’, which is pretty much what it sounds like: how the chocolate feels in your mouth. It is a phenomenon that is essential to your enjoyment of chocolate and, while you might not have thought about it, it something that chocolate manufacturers take very seriously.

One large chocolate manufacturer has turned to the science of neutrons to get to the bottom of the secret of the perfect mouth feel. They are part of a collaboration using ISIS to investigate how various ingredients affect the viscosity of molten chocolate and how that influences the feel of the chocolate in the mouth as it melts. They will be using this information to develop methods to manufacture at the molecular level that will lead to silkiest, smoothest chocolate possible.

Last updated: 25 February 2019

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