Janelee's chemistry thread



The caffeine in coffee is a mild stimulant, which acts positively in this respect. As the caffeine in coffee helps enhance alertness and attentiveness, this can lead to better performance at work as well as improve overall mood and it also works against fatigue.

There are many external stimuli, which may affect how long it takes someone to get to sleep. Some people experience a (mild) stimulating effect of caffeine when coffee is consumed shortly before going to bed. The effects are, however, very much individual-dependent. Some people find it hard to sleep after one cup in the early evening, whereas other people can drink coffee all evening without any effect on sleep. Anyone who is particularly sensitive can simply switch to decaffeinated coffee during the evening. There is no evidence to suggest that caffeine affects the quality of sleep, or different phases of sleep during the night.


It is often advised to cook the common white mushroom (Agaricus bisporus) before use, as raw mushrooms are considered toxic.

There are two reasons why it is advisable to cook raw mushrooms.

The common white mushroom contains a number of potential toxic substances, such as agaritine (figure A; (beta-N-(gamma-L-(+)-glutamyl-hydroxymethylphenylhydrazine), a derivative of glutamic acid (one of the common amino acids, the building blocks of proteins). On average, mushrooms contain about 15 mg agaritine per kilogram.

Agartine was found to be carcinogenic in mice, and is thus a suspected carcinogen for humans. More recent research, however, indicates that the risk for humans is very low. A daily intake of 10 grams of mushrooms would not result in a measurable increase in the incidence of cancer among the population.

In the liver agaritine is broken down to glutamic acid and hydrazine (figure B). The hydrazine is responsible for the carcinogenic properties of agaritine. As agaritine is not heat-stable, heating mushrooms (boiling, frying) further reduces the potential risk.

The second reason to heat mushrooms is to kill potential pathogenic bacteria. Mushrooms are commonly cultivated on horse manure. The manure is generally sterilised before use, but it is still a very rich medium for bacterial growth. There is thus a considerable risk for pathogenic bacteria to be present on raw mushrooms. Cooking (or frying) destroys the bacteria (including the potential pathogens) on the surface of the mushrooms.


Cocoa pods are harvested and split open to release the beans. The beans are embedded in a pulp. When the pods are broken the beans and pulp are sterile but they become contaminated with a variety of microorganisms from the pods, labourers hands, insects, vessels used for transport, etc.

The pulp surrounding the beans undergoes a fermentation process, which develops the colour and flavour of the beans. The initial anaerobic, low pH and high sugar conditions of the pulp favour yeast activity. Some research carried out revealed 24 strains of yeast on fermenting cocoa; another research by Rombouts identified 16 species. The fermentation process begins with yeasts converting sugars in the pulp to alcohol and carbon dioxide. Bacteria then start oxidising the alcohol into lactic acid and then, as conditions become more aerobic, acetic acid. This produces heat and raises the temperature in the first 24 hours. As the pulp breaks down and drains away bacteria continue to be active until fermentation is complete. The yeasts found during cocoa fermentation come from the surrounding environment, e.g., soil, trees etc. The species most frequently found at this stage are the Saccharomyces spp (in particular S. cerevisiae, Candida krusei, Kloeckera apiculata, Pichia fermentans, Hansenula anomola and Schizosaccharomyces pombe ). Research by Hansen and Welty shows that yeasts multiply very rapidly during fermentation and are able to survive drying and storage. One can find up to 107 yeast/gram in stored beans. After fermentation the cocoa beans are dried.

During the subsequent processing of the cocoa beans the beans are cleaned and can then undergo a form of thermal pre-treatment to separate the shell from the bean. One form of thermal pre-treatment uses infrared technology in which the beans undergo infrared radiation on a fluidised bed or vibrating conveyor. Water accumulates on the surface of the bean and bursts the shell. The high surface temperature induced by this process brings about a drop in the amount of microbiological contamination, especially yeast and other fungi. The beans are then separated from the shells and roasted. Following roasting the beans are turned into cocoa mass by grinding.

The quality of the cocoa mass is important due to the natural variability that exists in cocoa. Quality criteria for cocoa mass include figures for the number of yeasts found per gram - maximum 50 and for alkalised cocoa powder - a normal maximum of 50 with a limit of 100.
Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

Hmmm... sounds like another one of those paid Internet marketing schemes, brought to you by the United Alliance of Coffee Growers. Or, uh, Starbucks or something.

Heck, I don't care if it's a bot ploy -- I'll use this thread to talk about coffee. God, how I love coffee. Three to four cups a day, first thing I drink in the morning, greet the world with a smile -- hello, sunshine in a cup! I love making coffee in my french press, which leaves in the oils and the deep brewed flavor, especially with freshly ground beans and filtered piping-hot water. It's like heaven.

Any other coffee fans out there? Or is this more a dainty tea-with-milk crowd?
Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

I drink both tea & coffee but I rarely drink it black.

Usually some nice fresh milk from the local farm and some whole cane sugar.
Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

I only drink filter coffee now, settling on Italian style. I drink it black, with demerra sugar for now, till I give that up. You're supposed to drink good coffee el naturale.

Too much and I can't sleep, of course!
Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

I MUST have at least 2 cups of coffee with cream & sugar when I get up, Then I don't drink it after that till the next day.
I'm currently on my first cup for today. Pretty groggy-eyed and fat fingered.
Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

I just found out that they're building a Starbucks less than a mile from my house.

Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

Starbucks is deliciousness. Anyone who says otherwise is obviously wrong.

Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

I've only drunk take out star bucks and it was french style, bitter and watery. I guess they might sell full bodied filter coffee, but I've never drunk any. They are selling starbucks filter coffee in my local supermarket, but it is expensive compared to what I love to drink and don't want to take the risk unless told otherwise.

Educate me!
Re: Can coffee help increase alertness and attentiveness and decrease sleepiness?

I have no idea how Starbucks makes their coffee in England, Tim. A common American complaint is that Starbucks coffee beans taste "burnt" -- which I think is somewhat similar to people whining about dark beer being "bitter". Starbucks was the first national chain to really promote an international range of coffee beans, and helped impress upon the national consciousness the taste range of beans from Africa, Hawaii, South America and Asia.

Kevin has a legitimate beef that Starbucks essentially caters to the "yuppy" crowd, but that's hardly their fault -- and since they also teach about environmentalism and fair trade issues, maybe some good comes of it in any case.
I've merged Janelee's threads on caffeine, mushrooms and cocoa pods here so the chemistry lesson can be studied carefully
It's definitely filling a void in todays schoolkids education. Apparently sales on encyclopedias have been resoundingly low.
Back on topic... I am drinking a lovely cup of Starbucks Komodo coffee right now.

Starbucks coffee = deliciousness
In honor of our new Starbucks addicted moderator, I've added a new smiley. :D

Name: Deliciousness
Code: [noparse]:coffee:[/noparse]

The Sustainable Energy Use

Most people agree that sustainable energy is energy that is derived from a fuel that is renewable or will never run out and that results in minimal environmental impact. Consequently, the fossil fuels coal, oil, and natural gas clearly do not provide sustainable energy. Once used, those fuels are not replenished, and while they are burned they contribute to various forms of air pollution.
An example of a renewable energy source is one derived from plant materials, such as wood or grain. Plants can be regrown to replace those used for energy. However, plants are sustainable energy sources only if they can be replaced as quickly as they are used. In many areas of the world, trees are being cut for lumber or fuel at a much faster pace than they can be regrown. Such practices are not sustainable.

Plant materials, called biomass, are renewable and sustainable in the following

Anaerobic bacteria convert waste plant materials or animal manure to methane gas, and the methane gas (also present in natural gas) is burned either for heat or to make electricity (water is boiled and the steam turns a turbine).
Grain, such as corn, is converted to ethanol through a sugar fermentation process.

Ethanol is then mixed with gasoline, a fossil fuel, before being burned in an

The sun and wind are major sustainable energy sources that do not directly use a "fuel." Solar energy is used for direct heating of homes and water, or it is
converted directly to electricity using photovoltaic cells. Several large
demonstration plants using various techniques to concentrate the solar energy have been built to convert solar energy into electric energy.

The conversion of wind energy to electricity, using wind turbines, is now cost
competitive with fossil-fuel sources of energy such as natural gas. Wind-turbine
farms have been built in Europe and the United States. The land around them is still available for agricultural use. However, people have begun to resist the placement of wind farms in certain locations, citing noise, bird kills, and unsightly visual effects.

A future renewable energy source is hydrogen gas, which can be burned like natural gas or used in a fuel cell along with oxygen to make electricity, with only water as the final waste product. Hydrogen could replace natural gas if an economical method is found to extract it from water. The best future method is to use solar energy directly to "split" water to make hydrogen, and is a current area of research. An intermediate method, but still not used as of 2003, is to use photovoltaic cells to make electricity, which is used to electrolyze water to produce hydrogen. An unsustainable and energy-inefficient method is to use coal to make the electricity to electrolyze the water. As of 2003, fossil fuels, such as natural gas, are used to make hydrogen, which also is clearly unsustainable.

Some people have suggested fusion as a future energy source, based upon abundant supplies of deutrium in water and tritium from lithium and water. Technical problems have so far prevented this from occurring.
Aw, we finally reach poetic spamming and we cut the fun :smiley:

BTW, off to Starbucks tonight with the GF for tea/dinner

Apparently they serve sandwiches. It's across the road from the cinema where we will be watching Mama Mia (no Dark Knight on the cards unfortunately)

So, being an italian filter coffee drinker, what should I be drinking in Starbucks?
Tim, you might just want to get a double-shot of their espresso, although just about any one of their standard ground coffees ought to be robust enough to tickle your tastebuds.

BTW... my wife and kids drug me to see Mama Mia! last weekend. It is, surprisingly, not at all a bad movie. Pierce Brosnan is possibly the worst singer in the history of cinema -- I mean, really, they couldn't have cheated just a little and dubbed in American Idol's David Cook? -- but the rest of the cast makes it very worthwhile.

And Amanda Seyfried is gorgeous: