|
|
| Subscribe via itunes,yahoo or google |
< Previous Show | Next Show > |
7th Oct 2007
Brewing and Alcohol
|
|
This week, we're quenching our thirst for knowledge with the science of Beer and Brewing! We learn about how beer is made, why nitrogen is vital for the perfect pint of Guinness and why professors of brewing think they have the best job in the world. We also delve into the natural history of beer, to discuss the age old argument, what came first, the beer or the bread? We look into the future of beer, finding out how the chemistry of carbon dioxide could provide a purer pint. Also, a spicy way to specifically kill pain, saving slight with plastic corneas, and the hot, smelly sex lives of ancient plants. Plus, in Kitchen Science, Ben goes for the hard stuff by learning about distillation and the science of scotch.
|
|
|
|
|
|
|
Science News
|
The ability to selectively switch off pain whilst leaving other nerve pathways unaffected has been a holy grail of anaesthesia for decades. But now researchers in the US have cracked the problem... |
|
The cornea is the transparent layer that covers the front of the eyeball and protects it. But the cornea can become damaged, either through inherited disease or corrosion, and this can lead to b... |
|
Scientists have resorted to an unsual source of evidence to trace the history of volcanic eruptions on Earth and their effect on the climate - by studying paintings.The effects of historical eruptions... |
|
Last weekend Dr Kat was at the National Cancer Research Institute Conference in Birmingham, finding out about the latest advances in cancer science, and hobnobbing with some of the top researchers in ... |
|
Scientists in the US and Australia have shown that age is not a barrier to hot sex, at least when it comes to one of the world's oldest species of tree. Reporting their findings in the journal S... |
Interviews
|
Irene Terry, Univeristy of Utah
|
|
Chris Forman, Cambridge University
|
|
Professor Charlie Bamforth, University of California, Davis
|
|
Dr Dave Roberts, Natural History Museum; Dr Robert Simmons, Fishbourne Roman Palace & Julian Herrington, Master brewer.
|
|
Dr Ray Marriott, Botanix Ltd
|
|
Dr Mike Allison, Addenbrooke's Hospital
|
|
Chris Forman, Cambridge University
|
| Questions

|
I use morphine patches and if I forget to put one on I get the same withdrawal symptoms a heroin addict would! In the science news this week there was a story about using chilli combined with a pain killer to selectively kill pain. Could this be an alternative to morphine?
|
|
|
Well, the reason people have to use morphine is because it’s a very powerful painkiller and the downside of using morphine is that it does have these addicting qualities. If we can come up with a better way to block pain without producing these addicting qualities that would be really good news. The thing is that until now, no one has managed to do that, which is why I think this story is so powerful. You can home in just on the pain and not have side effects like morphine does such as addiction.
|

|
I sometimes brew my own beer. When I open a bottle of beer that I’ve brewed, sometimes it behaves nicely and fizzes up all over the place but this doesn’t seem to be correlated with how long the beer has spent in the bottle. Since I reuse the bottles I’m wondering, therefore, if some bacteria have got into the beer and they keep fermenting it in the bottle. Does this theory make sense and what other explanations might there be?
|
|
|
We put this question to Charlie Bamforth, Professor of Beer and Brewing at the University of California at Davis. You can hear the whole interview here.
Well, there’s all sorts of potential problems with brewing beer yourself. The key secret to brewing good beer is hygiene, hygiene, hygiene. It’s always possible that there’s residual sugar that’s not been fermented properly in the fermenter, that’s left behind in the bottle. Sometimes they may be leakers and the CO2 may come out of the cap. There are all sorts of possible explanations.
|

|
What makes Guinness® or stout so dark, thick and foamy and so good compared to the lighter, clear beers that you get elsewhere and places like the US?’
|
|
|
We put this question to Charlie Bamforth, Professor of Beer and Brewing at the University of California at Davis. You can hear the whole interview here.
Well, there are many excellent beers, some of them very light, some of them very dark. The colour of Guinness® is due to roasted cereal, roasted barley. They have a very intense heating process. The sugars and the amino acids and the grains are cooked together to give very, very dark colours. They give very roasted flavours. The foam: one of the main reasons why Guinness® foams so well is, apart from CO2 producing foam, they use nitrogen gas to give it extremely stable foams. The bubbles contain nitrogen gas and this is much more stable than CO2. Guinness® pioneered that technology.
|

|
My daughter recently went on a school trip and she was told that in Tudor times, if beers were poured with no head on them then they would put dead mice in the beer! Can you explain what this would achieve and why?
|
|
|
We put this question to Charlie Bamforth, Professor of Beer and Brewing at the University of California at Davis. You can hear the whole interview here.
I’ve never heard that one! There’s all sorts of crazy mythologies and truisms that people have handed down the ages. Possibly one of the things with mice is that some beer can get contaminated with Brettanomyces and Brett classically has a barnyard type, sometimes called a ‘mouse urine’, type of flavour. Maybe something’s got lost in the telling.
|

|
Lambic beers that are typically from Belgium use wild yeast and taste wonderful! So how much of the flavour of beer comes from the yeast itself?
|
|
|
We put this question to Master Brewer Julian Herrington...
As regards fermentations of all beers yeasts can give a predominant flavour depending upon the fermentation conditions and whether one uses lighter flavours from the malt, perhaps using rice as part of the recipe, for example and how much bitterness or hop character that’s used. So yeast produces fruit flavour which ranges from raisins in strong ales to a sort of peardrop and banana flavour in wheat beers. Though it can be all of the character of the beer (as in the latter example) or just part of it.
|

|
I caught a three inch long spider in my house with a special miniature vacuum cleaner designed to catch spiders. I didn’t know how to kill it so I coated it liberally with WD40. it took about five minutes to die, which I hope wasn’t too painful, so what was in the WD40 that killed it?
|
|
|
Chris & Kat discussed this question in the studio with Ray Marriott...
Kat: I think it’s probably blocked its breathing apparatus or something like that. That’s a horrible thing to do. You should let it out, let it run free!
Chris: Ray, what do you reckon?
Ray: Probably a solvent which is actually carrying the penetrating oil probably asphyxiated it first and then it blocked its spiracles afterwards.
Chris: Because most volatile things can act as general anaesthetics so when people inhale lighter fluid and things, they’re actually putting all that gas into their brain. It seems to cause brain cells to decrease their activity so it could be that it anaesthetised it and then, as you say, asphyxiated it.
Kat: Maybe it died high as a kite?
Chris: You never know.
|

|
(With regards using carbon dioxide to extract chemicals from hops) I assume the CO2 used in your fractionation process is part of the general CO2 found in the air and gets recycled accordingly?
|
|
|
We put this question to Ray Marriott of Botanix Ltd. You can read our entire interview with him here.
I think that’s a really interesting question. There are processes such as fermentation and the production of fertilisers which actually generate quite high volumes of carbon dioxide. It’s from these processes that we actually capture and purify the carbon dioxide and then use it for extraction. It’s then used in multiple extraction so it’s actually quite and efficient way of using it. And it’s actually a neat way of capturing CO2 from the brewing and fermentation process and reusing it to extract one of the raw materials.
|

|
Is there any danger to health from drinking cider?
|
|
|
Kat: I would think there probably is if you get really drunk, fall over, do something stupid.
Chris: Well, cider’s a little bit stronger than beer, on average, isn’t it? So, I would think enjoyed at the same rate as any other alcoholic beverage and within guidelines prescribed by the government and not more than 21 units per week for men or 14 units per week for women. I can’t see any reason why it would be worse for you but obviously in excess it’s gonna be bad. Do you think it counts as one of your five a day?
Kat: I don’t think it counts as a fruit and veg, no!
|

|
Why do we cry when we laugh?
|
|
|
I think that’s because you’re scrunching up your face in hysteria. It’s actually squeezing out the tears from your tear ducts. It’s also blocking the ducts in your nose so it’s all pouring out of your eyes.
|
Question of the Week
 |

|
Can you tell somebody's sex from their smell? (Perfume or aftershave doesn't count!) The jacobsons's organ, also known as the vomeronasal organ picks up extra information from a smell, but do humans have one?
|
| Brewing and Alcohol - More about this podcastBooze, glorious booze
This week on the Naked Scientists we’re off to the pub to look at the science of brewing. From the earliest pint to high-tech hops, we’ll be finding out how fermentation works, and hopefully sampling a glass or two along the way.
Professor of Beer
We’re joined this week by Charlie Bamforth, Professor of Brewing Science at the University of California, Davis. He’ll be taking us through the brewing process, explaining how to create beer and wine from simple ingredients and some humble yeast. But it’s certainly not a simple matter to make great ales – even tiny changes in the process or ingredients can dramatically affect flavour. We’ll be finding out how the appliance of science can help us make tastier beer, by altering the levels of critical chemicals. And is beer good or bad for us – could it be a source of important antioxidants, or does it just make us fat and unhealthy?
High-tech hops
Ray Marriot works for Botanix Ltd (www.botanix.co.uk), a company specialising in using liquid carbon dioxide to extract chemicals from natural sources such as plants. He’ll be telling us how his technique can be used to extract crucial molecules from hops – a key ingredient of beer – to give manufacturers more control over the brewing process.
“Past” out
Is binge-drinking a new phenomenon? Although alcopops are probably a product of modern times, you may be surprised to know that brewing is 12,000 years old – it’s even been dubbed “man’s oldest biotechnology” by Professor Bamforth. We sent Meera Senthiligam off to the Natural History Museum to find out about the Natural History of Beer. Find out if she came back in one piece by tuning into the Naked Scientists this week.
Cheers! |
|
|