Arabica Or Robusta – Introduction to Coffee Beans

Arabica Or Robusta – Introduction to Coffee Beans

If you are buying coffee beans for your home or business but you are not sure what you should be looking for, read on – this short guide will help you to understand the differences between the basic types of coffee, and bust the coffee jargon so you can decide which variety is right for you.

The coffee plant is native to Africa. The two main varieties of coffee plants are Arabica and Robusta. Arabica coffee originated in Ethiopia, while Robusta came from Uganda. Both types are now grown in several other regions throughout the world, and most coffee is labeled clearly to show which country and region it is from.

Generally speaking, Arabica is considered by coffee enthusiasts to be superior to Robusta, with a much stronger and more distinct flavor. Robusta can be bitter and/or milder-tasting – however the taste also varies depending on the region in which the coffee was grown and the processes it was subjected to during growing, shipping, storing and brewing.

Coffee is often described in terms similar to those you might find in wine tasting: the main three categories used are flavor (such as “sweet” or “spicy”), aroma (such as “flowery” or “chocolaty”), body (such as “medium-bodied” or “full-bodied”) and acidity (which refers to how “sharp” or “clean” the coffee tastes, NOT to its pH value).

When you buy coffee beans, you will probably buy them already roasted, however you can “home-roast” them if you choose. Roasting unlocks the flavor from the bean, and the extent to which beans are roasted varies. For example, you can buy “medium roast” beans, “Italian roast” beans (“Italian” refers to the roast – it does not indicate that the beans came from Italy), and so forth.

It is worth trying out different types of coffee, using the above points as a guide. You will be amazed at the range of flavors out there, and the more effort you take in trying the different flavors, the more of an expert you will become.

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Making Iced Coffee Drinks at Home

Making Iced Coffee Drinks at Home

Iced coffee beverages continue to grow in popularity. According to the National Coffee Association, between 2009 and the first quarter of 2013 iced beverage sales increased from 19% of menu items to 24%. Following the popularity of cappuccinos and mocha lattes, consumers are discovering that coffee is just as tasty – and even more refreshing – when served cold.

The percentage of American adults who drink iced coffee is 2%, but a much higher number (38%) of young Americans between 18 and 24 drink iced beverages.

Iced coffee can be as easy to prepare as iced tea. A variety of options, such as flavoring syrups, cold milk, chocolate and spices, allow you to create personalized coffee concoctions that are just as delicious as those served in your favorite coffeehouse.

The first office-quality iced coffee machine was released in 2008. In 2010, Keurig introduced the brew-over-ice theme. Major brands are creating products for the vending machine industry.

Increasingly popular beverages such as iced vanilla mocha, iced rum coffee and iced latte are easy to make at home.

Here are some tips for refreshing iced coffee drinks.

  • Don’t let your iced drinks become watered down. Fill an ice tray with fresh-brewed coffee instead of water, and use the frozen coffee cubes to cool your iced coffee drink without losing any flavor.
  • Pour the flavoring syrup into the cup first. To complete the drink, pour in espresso or coffee, then the ice, and top it off with cold milk.
  • Use a machine that produces a high quality coffee or espresso for your foundational coffee. Some coffee machines, for example, grind coffee beans right before brewing and allow you to control the strength of your coffee.
  • Be creative. Add a personalized touch to your iced coffee beverages with whipped cream, chocolate shavings, nutmeg or cinnamon. It is easy to make fancy chocolate curls from a chocolate bar using a vegetable peeler.
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Coffee Houses Have Always Offered Much More Than Coffee

Coffee Houses Have Always Offered Much More Than Coffee

When many people in the world want to go somewhere to exchange news, share ideas and get advice, they often go to a coffee shop. It has been that way for quite some time. Coffee shops have been places of learning; of making business deals; scientific, literary, political, philosophical, and economic discussions; and even the oh-so-common gossip.

In the earliest part of their history, coffee houses were already so popular that ideas born from there have been a source for political forums and discussions ever since. The inspiration of brilliant, coffee-inspired thinking is to the point that, at times, kings and nobility used it as a method of determining public opinion.

When coffee was introduced to Europe, during the 17th century, the popularity of cafés followed the same pattern as most coffee houses around the world still do today. The café quickly became a venue for people to congregate, exchange views, write poems, plays, and political testaments, conduct business transactions, participate in cultural exchange and often relax with a good book. In those earlier days when were the were no postal addresses, the popularity of coffee shops also served well as a mailing address, because so many people were regulars.

A typical coffeehouse shares common characteristics with bars or restaurants. They differ in that a coffeehouse focuses on serving just coffee, teas and snacks. In some countries, however, coffeehouses do serve hot meals, deserts, sandwiches, soups, and alcohol, as well as from bakery products.

Today, coffeehouses continue the tradition set by coffeehouses of the past. They still remain a very popular venue for people who want a relaxed and calm atmosphere where they can talk, read, catch up on the day’s event, meet with people and have excellent quality coffee. This desire is evidenced by popular coffeehouses with franchises around the globe such as Starbucks, Seattle’s Best Coffee, Peet’s, Cup O’ Joe, The Second Cup and the Coffee Bean.

Depending on the country and region, coffeehouses have adopted variations. In the United States, coffeehouses or cafes may offer a variety of coffee styles, hot chocolate and teas, as well as light snacks, while others serve full menus. Alcoholic beverages may even also be offered. One of my favorite types of coffeehouse also offers cases of books that may be read as you slowly enjoy your coffee.

Cafes in France almost always serve alcoholic drinks. Like most cafes anywhere in the world, they also serve light snacks. Other coffeehouses may have a restaurant area where the guests could be served from the full menus. The popularity of cafes in France, especially Paris, gave way to subtle coffeehouse variations like the brasserie where single dish meals are typically served, and the bistro.

The café experience in Europe spawned other variations of coffeehouses around the world. Some of these coffeehouses offer curb-side seating and others outdoor seating in places like the sidewalk, pavement or terraces. The seating is usually clustered along busy streets and operated by private local establishments and the activities often very closely resemble parties, especially on weekends.

These patio coffeehouses provide more open public spaces commonly preferred by customers wanting an airy and very casual atmosphere for relaxation and conversation.

Recently, a new type of coffeehouse entered the industry: the Internet café. Internet cafes may not appear to be your typical coffeehouse like the bistro, brasserie, cafeteria and the coffee chain establishments but they certainly share the same basic characteristics. Coffee, tea and chocolate are served together with light snacks and chatter. The chatting, though, is done online.

The Internet coffeehouse may not replace the traditional coffee shops, but nevertheless, Internet cafes are also a hub for political exchange, learning, and journalistic, literary and commercial enterprise. Only the styles of coffee shops have changed over the centuries, but in respect to why people frequent them, nothing has really changed.

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The Perfect Cup of Coffee Boils Down to Four Factors

The Perfect Cup of Coffee Boils Down to Four Factors
This entry is part 2 of 2 in the series Chemistry of Coffee

By Don Brushett

Welcome to the second instalment in our series Chemistry of Coffee, where we unravel the delicious secrets of one of the most widely consumed drinks in the world. Here we look at how tweaking variables can make the difference between a velvety smooth coffee or a scalding, bitter mess.


It’s hard to get a bad coffee these days. Plenty of baristas have fine-tuned the process of making espresso, but really there are only a handful of variables they can control:

  1. coarseness of the grind
  2. temperature of the extraction
  3. extraction time
  4. the all-important coffee-to-water ratio.

Coffee roasters and barista schools have produced many impressively complex charts plotting grams of coffee against volume of water overlaid with concentration and yield. In the middle is the ideal weight/ volume/ concentration yield target for the perfect cup of coffee.

(Of course, if you prefer a latte, cappuccino or flat white, the milk is a whole other story.)

Here is a little graphic of my own that I will use to describe what happens when we change our four variables.

 

On the horizontal axis we have relative time, on the vertical axis the numbers represent amount. The curves are extraction profiles.

Caffeine is very water soluble and the vast majority of the caffeine is extracted early. The volatile oils, which give coffee its complex flavour and aroma, extract more slowly. The organic acids, which make coffee taste bitter, are extracted the most slowly of all.

So let’s go through each of our four variables in turn.

1. Grind

The coarseness of the grind and the extraction time are inextricably linked. The finer a coffee is ground, the more surface area there is. Conversely, the larger the grind, the smaller the surface area.

Let’s consider the two ends of the extreme. If we grind coffee as fine as talcum powder we have maximised the surface area available for extraction. Therefore, we can very quickly extract the target compounds – but perhaps too quickly for some people’s tastes.

Mark/Flickr, CC BY-NC-ND

Turkish coffee is very finely ground and boiled. This produces a coffee which is very strong and bitter and because of the fineness of the grind often contains a lot of suspended solids (muddy). The finely ground material may block filters too, causing the extraction to go on for too long – or not allow the water to pass through at all.

At the other end of the spectrum, let’s consider whole coffee beans. Of course, given enough time, we can extract unground coffee. This is quite wasteful of the coffee beans because the hot water may not penetrate all the way to the interior of the bean, so we throw away unextracted material.

Obviously, the optimum grind (coarseness) is somewhere between these two extremes, where we match the residence time of the hot water (flow rate) across the ground coffee beans with our ideal caffeine/ volatile oil/ organic acid ratio.

If you get a cup of coffee produced from a quality bean but it is too weak and insipid, the coffee may have been ground too coarsely. If the coffee is unacceptably bitter, perhaps the grind is too fine, with too-high levels of organic acids being extracted.

2. Temperature

Let’s hold all of our variables except temperature constant and see what happens. As with our coarseness experiment let’s consider the two ends of the extremes.

Temperature strongly influences solubility and rates of extraction. Yes, you can extract coffee with ice water. The three curves on our graph above get pulled to the right, so given enough time we can extract a decent cup of coffee. Cold brew coffee is made this way – ground beans are placed in cold water and allowed to “brew” in the fridge for up to a day.

Coffee can be extracted in the fridge overnight.
jodimichelle/flickr, CC BY-SA

The solubility of caffeine is moderately affected by temperature and the solubility of the organic acids is strongly affected by temperature. We would expect that a coffee brewed using this method would be lower in caffeine and much lower in bitterness than a coffee brewed using hot water.

Now, let’s extract our coffee using boiling water. The curves on our graph get scrunched up on the left-hand side. Everything gets extracted much quicker and the margin for error becomes much smaller if we try to limit bitter organic acid content.

Another complicating factor is that our volatile oils are just that – volatile. If we boil coffee, our flavour and aroma compounds get carried away in the steam. This can produce a coffee that is weak in taste, yet high in caffeine and organic acids.

3. Time

Let us keep our coarseness, temperature and water-to-coffee ratio variables constant and only consider the time variable. If we consider the ideal cup of coffee is one that has maximum caffeine and maximum volatile oils while limiting the bitter organic acids, we would consider 4 on our arbitrary timescale to be just about perfect.

If we only extract to 2 on the timescale we will have a coffee high in caffeine but weak, or underdeveloped, in flavour, aroma and bitterness. If we extract for too long, say to 8 on our timescale, our coffee will contain high amounts of organic acids, which can make it unacceptably bitter.

mckln/flickr

4. Coffee-to-water ratio

This brings us to our coffee-to-water ratio – perhaps the most subjective of all our tests. Too little coffee and even with all our variables optimised the coffee will taste weak. Too much coffee and the resulting brew will be too strong and overpowering.

This ratio depends on choice of extraction method:

  • for a French press, or plunger, where the temperature of the water drops quickly, we need to have more coffee per unit of water
  • if using a drip filter, the water temperature is higher than that in a plunger so a lower ratio is needed
  • in modern espresso machines the volume of water can be changed to taste.
    Generally, the water temperature is maintained within the machine at around 97C. Too little water and the coffee is weak and underdeveloped; too much water and the coffee is bitter.

The generally accepted rule of thumb for the coffee-to-water ratio is approximately 10g of coffee to 200mL of hot water. One heaping tablespoon is about 15g, give or take a gram or two.

So there you have it. Optimise the coarseness of the grind, match this with the water temperature and the extraction time and make sure your coffee-to-water ratio is in the right ballpark. Or you can go down and visit your friendly local barista, have a chat, and let them do the thinking for you.


Further reading: Wake up and smell the coffee … it’s why your cuppa tastes so good

The Conversation

Don Brushett does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation.
Read the original article.

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How to Make World Class Gourmet Coffee Every Time

How to Make World Class Gourmet Coffee Every Time

Did you know that you can make a nice cup of gourmet coffee on your own at home? Here are some simple steps to brewing the perfect cup of coffee every time.

Start with Quality Beans.

One of the most critical aspects of brewing satisfying gourmet coffee is the grade of the coffee you start with. If you have a favorite flavor, purchase whole beans in that flavor. If you do this, it will allow you to start with the freshest, most flavor-filled coffee possible.

Grind Away.

Purchase a quality coffee grinder. The best grinders available today are fairly low cost, easy to use and easy to clean up. By grinding your own coffee beans, you’ll be able to only grind what you need, meaning that you will have complete freshness in your coffee.

Store It Right and Tight.

It is very fundamental to store your coffee tightly sealed. Air oxidizes the coffee and can make it turn bitter quickly. Metal canisters may also impart a metal taste to into the coffee, making it taste bad.The best solution is to use a plastic or ceramic airtight container for your coffee and coffee beans.

Also, store the coffee at room temperature because the moisture in the fridge or freezer can make it go bad faster. But if you think you won’t be using all the beans soon, freezing them is fine and will help them keep fresh-tasting longer.

The Maker Is Crucial.

The coffee maker that you choose to use, and its condition, is also critical to that gourmet cuppa. No matter what style of coffeemaker that you choose, you can get a good cup of coffee out of it if you take the essential steps to keeping it working at its best.

For example, you should ensure that the coffee maker is cleaned after each use. In fact, you’ll need to detail clean it, with the assistance of vinegar water, every so often as well. Your preferences can determine which style of coffee maker you will use. A coffee maker with a permanent filter in it is a good idea.

It’s the Water.

Even the water that you use is central to the quality of the coffee you will make with it. It is essential that you use water that is free from chlorine and too many minerals. Often, using bottled water rather than tap water will augment the quality of the coffee. Also, keep the water nice and hot. A good temperature for the water when it hits the coffee is about 200 degrees Fahrenheit (93.3 Celsius).

Use the Right Amount of Coffee.

It is also of utmost importance for you to use the right quantity of coffee grounds in the coffeemaker. Too much ground coffee and you will have a very strong cup of coffee and too few will make it to be too weak. Follow the directions provided by the coffee producer for the best cup of coffee.

Lastly, and probably the most vital aspect, of getting a great cup of gourmet coffee is to make sure to enjoy your coffee when it is hot and fresh. Most restaurants are told to keep coffee for less than thirty minutes, but at home, the best tasting coffee is the coffee that was just brewed, or at least that hasn’t sat for more than twenty minutes since it was brewed.

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Longer Life Through Coffee Drinking?

Longer Life Through Coffee Drinking?

By Ian Musgrave

Coffee, the worlds number one stimulant, may increase your lifespan (a little bit)
Ian Musgrave

There is a persistent belief that drinking coffee is bad for you. Some alternative medicine systems eschew all coffee drinking (but are enthusiastic about coffee enemas). Certainly if you overindulge the sleeplessness and tremors will remind you of the perils of too much of a good thing. But there is a longstanding belief that long term consumption of coffee is in some nebulous way “bad”. This is despite coffee being packed with the sorts of antioxidants you would pay good money for at the health food store.

Now a new study suggests that people who drink coffee are less likely to die.

Wow! Great! I’ll just fire up the espresso machine then.

Hold on, firstly, the effect is modest, you are around 10% less likely to die if you are drinking 6 or more cups of coffee a day. Secondly, it’s an association. We don’t know if it’s the coffee drinking leading to less death, or something else which coffee drinkers are more likely to do.

Oh, so I should pack the espresso machine away.

No, there is now a fair bit of evidence that modest coffee consumption can give you some degree of protection against things like Parkinson’s Disease and Alzheimer’s disease (again though, we don’t know if it’s coffee per se that gives protection, or something else that coffee drinkers do). And coffee tastes good too.

But the apparent health benefits of any food or beverage should not be an excuse to overindulge, like the people who use the reported benefits of drinking modest amounts of red wine as an excuse to drink bottles of the stuff in one go.

So while I get the espresso going, what is the latest evidence?

A research team followed a group of nearly 400,000 people for 14 years, or until they died ( whichever came first). They gave the people extensive questionnaires about coffee drinking, food consumption, lifestyle and measured a range of health parameters at the start of of the study. Then after the 14 years they looked at the death rates in coffee drinkers and non-coffee drinkers.

They found that more coffee drinkers died.

Wait! What!

That’s the problem with looking at these sorts of studies simplistically. There are a whole other bunch of factors that influence death rates. In epidemiology speak these are called “confounders” (because They confound interpretation). It turns out that most coffee drinkers also smoke, so the increased death rate was due too smoking differences between coffee and non-coffee drinkers.

If the researchers had not measured smoking rates in the people, they would have been fooled into thinking that coffee was bad for you. This is also why we say that the coffee drinking – less death is just an association, the increased life-span could be due to something that wasn’t measured, even though lots of things were measured.

So how did they work out coffee drinking was good for you?

In epidemiology speak they “ controlled for the confounders”. If you compare just smokers who don’t drink coffee with those that do, coffee drinking smokers livers longer than non-coffee drinking smokers. Of course, it’s not quite as simple as that. When you have a lot of measurements you have to do some clever mathematics to sort it all out.

So is it a good study?

Yes, they had a big group of people they followed for a sufficiently long time, they only looked at people who were reasonably healthy when they started following them (so disease progress patterns couldn’t mess things up) and they measured a heck of a lot of lifestyle factors.

One problem is, as the researchers point out themselves, that they only asked people about their coffee consumption at the beginning of the study. So they had no way of knowing if people decreased or increased their consumption, or switched to or from decaf.

Another thing they didn’t measure was the type of coffee, apart from crudely separating caffeinated from non-caffeinated. So we have no way of knowing if most people were drinking Floor-Sweepings brand instant coffee or Heart Burtser double espressos.

The latter information is important if we want to generalise to other populations. US coffee as generally consumed is somewhat different in strength to how the Europeans take it. I vividly remember visiting a friend of mine in Seattle. At the time I was working as a postdoctoral student in Berlin. There was an industrial strength filter coffee machine outside my lab door, pumping out vicious black heart starters almost 24/7. My mate proudly took me to the street in Seattle where he claimed the best coffee in the US was served.

It tasted like pinkelwasser. That is not a compliment.

Sounds uninspiring, so how is coffee making people live longer?

Chlorogenic acid, a key antioxidant in coffee
Ian Musgrave

We know how it’s not doing it. It’s not caffeine, as decaffeinated and caffeinated coffee had pretty much the same effect (except for injuries and accident, where caffeinated coffee was a clear winner).

Coffee is chock full of antioxidant chemicals such as polyphenols and Chlorogenic acid. We know that people who consume foods rich in antioxidants have better health outcomes and live longer than people who don’t. We also know that feeding people pure antioxidant vitamins is a waste of time. The antioxidant status of food may be unrelated to health, but may be a marker for something else in these foods.

So whether it’s the antioxidants in coffee is unclear. This hasn’t stopped companies from adding extra antioxidants to instant coffee though (although they were doing this well before this study came out). Maybe it’s something completely unrelated, like coffee drinkers are more likely to walk to their local coffee shop, getting a bit more exercise.

So if I want to live longer?

Choose you parents carefully, eat plenty of fresh fruit and vegetables, get more exercise, develop or participate in social networks. Why not walk down to your local coffee shop and share a cappuccino with your friends?

Coffee’s ready

Milk and two sugars please.

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Ian Musgrave does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation.
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Moderate amount of coffee doesn’t dehydrate you

Moderate amount of coffee doesn’t dehydrate you

By Annabel Bligh, The Conversation

There is no evidence for a link between moderate coffee consumption and dehydration, according to a study in PLOS ONE.

The global population consumes 1.6 billion cups of coffee a day and it’s a common belief that coffee is dehydrating. But the tiredness, headaches, dizziness or light-headedness that can result from even mild dehydration is unlikely to be caused by the daily cup, researchers said.

Lead researcher Sophie Killer, a sports nutritionist, was particularly interested in the effects of coffee drinking on people’s daily balance of fluids. She wanted to know whether regular intake of coffee resulted in chronic low-level dehydration – something that may inhibit athletic performance and recovery.

Killer and colleagues studied 50 male participants in two phases. They were required to drink four mugs (200ml) of either black coffee or water per day for three days and then vice versa. Using a variety of well-established hydration measures – including body mass and total body water, as well as blood and urine analyses – the results showed no significant differences between those who drank coffee and those who drank water.

The researchers even go as far as to say that coffee has similar hydrating qualities to water when consumed in moderation.

There has been a raft of research into the good, the bad and the ugly sides of coffee consumption. Caffeine is a naturally occurring stimulant, ingested by most of us on a daily basis through coffee, tea and chocolate consumption.

It has been known since 1928 that caffeine is also a mild diuretic, so you might be forgiven for thinking that drinks such as tea and coffee which make you urinate more could lead to dehydration.

“Caffeine is only a mild diuretic,” Ian Musgrave, Senior Lecturer in Pharmacology at the University of Adelaide, said. “And our usual exposure to it is through drinking beverages such as tea and coffee that provide added fluid.”

Killer said “numerous studies have documented the body’s ability to develop a tolerance to caffeine’s acute diuretic effects.” And tolerance can be acquired in as little as four to five days of consuming caffeine regularly, even at low doses.

This means regular caffeine drinkers should not experience a need to visit the loo any more often than non-caffeine drinkers.

The debate over whether or not coffee is good or bad looks set to continue, but perhaps the key word in the findings is moderation. The study adds to a body of evidence that suggests that moderate tea and coffee consumption isn’t associated with significant adverse health effects.

The study comes a day after the advertising watchdog banned a multimillion-pound Lucozade Sport ad campaign for claiming it hydrated better than water.

But when it comes to coffee both Killer and Musgrave hope it will put to bed the old wives’ tale that coffee is dehydrating once and for all.

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Wake up and smell the coffee … it’s why your cuppa tastes so good

Wake up and smell the coffee … it’s why your cuppa tastes so good
This entry is part 1 of 2 in the series Chemistry of Coffee

By Don Brushett

Welcome to our three-part series Chemistry of Coffee, where we unravel the delicious secrets of one of the most widely consumed drinks in the world. So while you enjoy your morning latte, long black or frappe, read on to find out why it tastes so good – you might be surprised to discover what’s in your cup.


Most of what we taste we actually smell. The only sensations that we pick up in our mouth are sweet, sour, bitter, umami and salty. Without its smell, coffee would have only a sour or bitter taste due to the organic acids. Try it with your next cup of coffee – hold your nose as you take your first sip.

The rich satisfying sensation of coffee is almost entirely due to the volatile compounds produced when we roast coffee beans.

The compounds that are formed in the roasting process are very similar to any other compound that is formed in the cooking process. The smell of baking bread is from compounds produced when a sugar reacts with a protein in what is called a Maillard reaction.

Not every scent is as welcoming as freshly baked bread, though. Our sense of smell has developed over millennia to detect dangerous compounds.

Cadaverine and putracine, produced in rotting meat, can be detected by our nose at very low concentrations. The same can be said of sulphur-containing compounds such as hydrogen sulphide – rotten egg gas – which is detected by our nose at levels of parts per billion.

Coffee has some of the same ‘scent’ compounds as freshly baked bread.
jm_photos/flickr, CC BY

The upshot of this is that we do not detect all compounds in our surroundings to the same extent. For example, to us water is completely odourless although it may be very concentrated in the atmosphere.

Odour chemists have developed a system called odour activity values which show how we respond to particular compounds. This has an influence on how we experience a complex mixture of stimuli.

Flavourists and perfumists have developed a series of descriptors, or words that are used to describe a particular smell. Using gas chromatography equipped with a sniffer port, chemists are able to smell individual compounds as they come off the gas chromatography column and apply a description to what they experience.

Words such as fruity, earthy, flowery, caramel-like, spicy and meaty are used to describe the odour of individual compounds. It is this complex mixture of volatile organic compounds that we can identify with a particular food. The smell of baking bread can easily be distinguished from the smell of cooking cabbage; a lamb roast from a pork roast.

Yet it is not one compound that is responsible for the odour that we experience, but a complex mixture of hundreds of different compounds.

What we smell in coffee

Approximately 800 different compounds are produced in the coffee-roasting process. These thermal degradation reactions decompose sugars and proteins to form the volatile compounds that we smell.

Most of these reactions take place within the thick walls of coffee bean cells, which act as tiny pressure chambers. Not all of these 800 compounds cause the same response in the olfactory membrane in your nose, though.

Green (unroasted) coffee tastes very grassy when brewed. You still get the organic acids and caffeine in the brew but it lacks the full sensation because there are few volatile compounds due to the lack of roasting.

The profile of roast coffee includes only 20 major compounds, but it is the influences of some of the minor compounds that determine the overall taste that we experience.

When chemists are analysing the volatile compounds in coffee a huge range of different odour qualities are experienced.

Some of the nitrogen-containing compounds such as pyridine can actually smell quite foul, while others can smell quite fruity.

Other compounds have descriptors such as putrid or rancid. One compound, 5- methyl furfural, is described only as coffee-like. But it is the rich mixture of hundreds of different volatile compounds that, when we smell it, can only be described as “coffee”.

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Don Brushett does not work for, consult to, own shares in or receive funding from any company or organisation that would benefit from this article, and has no relevant affiliations.

This article was originally published on The Conversation.
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Coffee is Valuable in Many Ways

Coffee is Valuable in Many Ways

Coffee has changed the way that people approach life all over the world. Billions of people use coffee for various reasons, but mostly either for a pick me up or because they really do enjoy the taste of the coffee. You will find that the legends about the coffee plant goe clear back to 500 BC where it was discovered in Ethiopia. It was later taken to Arabia, and that is where coffee got its name.

During the Renaissance, not only did the roasting and brewing of coffee come to be considered an art, but it was basically commercially produced. By the end of the Renaissance and the beginning of the 19th century coffee began to be appreciated all over Europe, Asia, the Middle East, and in both South and North America. Coffee was a luxury that nearly all classes could afford.

Coffee is traded on many of the stock exchanges and there are billions of dollars earned from sales of coffee each year. Coffee, especially gourmet coffees and fancy coffee recipes, has become quite a moneymaker. After petroleum, coffee is the world’s second- or third-most valuable commodity (disregarding illegal commodities). The global coffee market is worth at least $70 billion annually, and possibly as much as $100 billion.

Each year, more than 500 billion cups of coffee are consumed worldwide, and according to industry analysts, the market is far from saturated. In the United States, for example, coffee consumption per person annually is 23 gallons, and that is far less than the amount that was consumed back in the 1040’s, so the market is far from saturated. For coffee producers and sellers, these figures represent growth potential, especially as nutritional science increasingly demonstrates that coffee, when consumed in moderation, does have significant health benefits.

People in the past thought that coffee had miraculous health effects. And, in fact, in modern times it has been theorized that caffeine stimulates male sperm. There have also been some studies that indicate that Diabetes or Prediabetes can be helped by coffee because it will helps to prevent Cirrhosis of the liver, and can improve the way that people are affected by Asthma.

Coffee contains antioxidants much like red wine does and studies show that regular coffee drinkers have a lower incidence of heart disease. However, there are still things about coffee that you should pay heed to, especially when it comes to the amount that you use.

Like nearly everything in life, there are pros and cons. Coffee contains caffeine, which is a stimulant and can improve alertness in reasonable quantities, but may raise blood pressure and stress levels if too much is consumed. Coffee is also a diuretic and it will encourage the body to take frequent pit stops, and if you have certain health challenges your doctor may advise you to avoid it or to limit your consumption.

There are many ways that you can use coffee and there are many different types of coffee grown all around the world. Exploring the world of gourmet coffee can be a fun and educational experience.

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Coffee Pros and Cons

Coffee Pros and Cons

There have been so many studies and reports about the effects of coffee over the recent decades that many people are confused about the real results.

For a number of years we were told that coffee drinking was unhealthy, but now more recent studies tell us that is not true. Over four hundred million cups of coffee are consumed per day in this world, so of course this is an important issue.

The main problem that people may have is with the caffeine in coffee. Caffeine is a mild stimulant, and therefore raises blood pressure and can increase heart rate. This was of concern to earlier researchers; today, researchers think the effect is so mild and short-lived as to be negligible.

In fact, we are actually hearing about the benefits of coffee consumption. Some studies have even shown that the consumption of coffee reduces the incidence of colon cancer, but at such high levels that the negative effects of coffee may once again be an issue. But moderate levels of coffee drinking may actually be good for us. We know that it helps keep us alert. It has been discovered that wine contains certain antioxidants that help prevent heart disease and some cancers by removing free radicals from the blood system. The same may be true of coffee. Studies have shown that the concentration of antioxidants in coffee is greater than in cranberries, apples or tomatoes. Of course, those other fruits and vegetables also give us many other benefits such as vitamins, minerals and fiber.

Chinese studies have indicated that coffee consumption reduces the effects of Parkinson’s Disease. Some studies in both America and Scandinavia indicate that coffee may reduce the risk of Type 2 Diabetes. And there is growing evidence that coffee can reduce the incidence of kidney stones and gallstones. Benefits have also been noted in the digestive system, since caffeine stimulates the production of stomach acid, aiding in digestion. In moderation, the consumption of coffee has been shown to reduce the constriction of the airways in asthma sufferers. A bronchodilator called theophylline, contained in coffee, helps this effect.

But, of course nearly everything, even things as good as coffee, also has negatives. Excess coffee consumption has been linked with infertility or reduced fertility. Higher blood levels of homocysteine and LDL cholesterol have been associated with coffee drinking; these are both factors in coronary heart disease. Since coffee contains cafestol, which raises blood cholesterol, this is one of the main reasons it has been indicted in the heart disease debate. However, the European method of making coffee, which is to boil the ground beans, is the real culprit in cafestol; the American method of percolating or filtering coffee removes it.

Another issue that has been raised regarding coffee drinking is that coffee may contribute to loss of bone density in women. In addition, women who drink four or more cups of coffee a day may be prone to incontinence.

The bottom line? As always, is moderation. The many benefits of drinking coffee are available, and the risks avoided, if coffee is drunk moderately. Get a one cup coffee maker and enjoy one or two good cups a day, or splurge on your cappuccino instead of endless cups from the coffee vending machine.

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