CHEMIFIED once again.

What's Your Flavour?

2009-07-21T00:26:00.000-07:00

What does FLAVOUR mean?
Flavour is the sensation produced by a material taken in the mouth, perceived principally by the senses of taste and smell, and also by the general pain, tactile and temperature receptors in the mouth.
Flavour also denotes the sum of the characteristics of the material which produce that sensation.
Flavour is mainly composed of taste and odor. Texture has a very definite effect, smoothness, roughness, granularity, and viscousity can all h

What influences FLAVOUR?
TASTE
ODOR
TEXTURE
~smoothness roughness granularity viscosity~
OTHERS
~hotness of spices coolness of menthol brothiness or fullness of certain amino acids metallic alkaline~

TASTE
It is generally agreed that there are only FOUR BASIC or TRUE tastes; sweet, bitter, sour and salt. The sensitivity to taste is located in the taste buds of the tongue. There is a regional distribution of the four kinds of receptors to create areas of sensitivity.

Chemical Structure and Taste
A first requirement for a substance to produce a taste is water-solubility. In general it can be said that all ACID substances are SOUR. Sodium chloride and other salts are salty, but as constituent atoms get bigger, bitter taste develops.

Minor changes in chemical structure may change the taste of a compound from sweet to bitter or tasteless.

The Effect of Substitutions in Saccharin on Sweetness

Saccharin is 500 times sweeter than sugar(pic above). Introduction of a methyl group or of chloride in para position reduces the sweetness by half. Placing a nitro group in the meta position makes the compound very bitter. Introduction of an amino group in the para position retains the sweetness. Substitutions at the imino group by methyl, ethyl or bromoethyl groups all result in tasteless compounds. However, introduction of sodium at this location yields sodium saccharin which is very sweet.

SWEET TASTE

Oh! So tempting!
According to AH,B theory, all compounds which bring about a sweet taste response possess an electronegative atom A, such as oxygen or nitrogen. This atom also possesses a proton attached to it by a single covalent bond and, therefore, AH can represent a hydroxyl group, an imine or amine group, or a methine group.

The AH,B system present in sweet compounds is, according to Shallenberger, able to reach with a similar AH,B unit which exists at the taste bud receptor site through the formation of simultaneous hydrogen bonds. The relatively strong nature of such bonds could explain why the senses of sweetness is a lingering sensation.

SOUR TASTE

*cringes*
Although it is generally recognized that the sour taste is a property of the hydrogen ion, there is no simple relationship between sour taste and acid concentration.

SALTY TASTE

MSG aint good! nuh-uh
The salty taste is best exhibited by sodium chloride. It is sometimes claimed that the taste of salt by itself is unpleasant, and that the main purpose of salt as a food component is to act as a flavour enhancer or flavour potentiator. The taste of salts is dependent on the nature of both cation and anion.

BITTER TASTE

Oh gourd, they are friggin' bitter..
The bitter taste is widely distributed and can be attributed to a great variety of organic and inorganic compounds. Although bitter taste by itself is usually considered unpleasant, it is a common component of the taste of many foods usually in combination with sweet and sour.

Our chemical world ♥

2009-07-18T10:31:00.000-07:00

Here are some chemistry videos which makes learning interesting!

Chemical Party

The Element Song

Lyrics anyone?
There's antimony, arsenic, aluminum, selenium,
And hydrogen and oxygen and nitrogen and rhenium,
And nickel, neodymium, neptunium, germanium,
And iron, americium, ruthenium, uranium,
Europium, zirconium, lutetium, vanadium,
And lanthanum and osmium and astatine and radium,
And gold and protactinium and indium and gallium, (gasp)
And iodine and thorium and thulium and thallium.

There's yttrium, ytterbium, actinium, rubidium,
And boron, gadolinium, niobium, iridium,
And strontium and silicon and silver and samarium,
And bismuth, bromine, lithium, beryllium, and barium.

There's holmium and helium and hafnium and erbium,
And phosphorus and francium and fluorine and terbium,
And manganese and mercury, molybdenum, magnesium,
Dysprosium and scandium and cerium and cesium.
And lead, praseodymium and platinum, plutonium,
Palladium, promethium, potassium, polonium,
And tantalum, technetium, titanium, tellurium, (gasp)
And cadmium and calcium and chromium and curium.

There's sulfur, californium and fermium, berkelium,
And also mendelevium, einsteinium, nobelium,
And argon, krypton, neon, radon, xenon, zinc and rhodium,
And chlorine, carbon, cobalt, copper, tungsten, tin and sodium.

These are the only ones of which the news has come to Hahvard,
And there may be many others but they haven't been discahvered.

Alcohol through fermentation

2009-07-07T09:54:00.000-07:00

Instead of garbage enzymes from my previous post, this post is more on EDIBLE enzymes. Had this idea when my aunt made some really great tasting dragonfruit enzyme drink. Before I proceed in typing about the methods to make the dragonfruit enzyme, I shall explain about alcohol since they're both related.

ALCOHOLAlcoholALCOHOLAlcoholALCOHOLAlcoholALCOHOLAlcoholALCOHOLAlcoholALCOHOL

When majority of the population hear or see this word, the first thing they would think of is alcoholic beverages like beer, wine, liqueur, vodka etc. Not all alcohols are edible (or should I say drinkable). Or..If you are willing to risk your lives, all alcohols can be consumed but many are poisonous and can lead to death. Some alcohols are used in the sterilizing apparatus or removing bacteria.

Some cleaning agents containing alcohol:

Here are some examples of alcohol's chemical formula:

Ethanol is one of the few alcohols available in any quantity as a natural product. The properties of "alcohol" or ethyl alcohol have been known since people first collected fruits and grapes and allowed them to ferment. Fermentation is the breakdown of carbohydrates in the presence of an enzyme catalyst into smaller compounds. Ethanol is a product of the fermentation of plant materials which contain carbohydrates -- fruits and grains. The natural fermentation solution from grapes achieves a maximum alcohol content of about 12% in wine. On exposure to oxygen, the ethanol is oxidised to acetic acid and the solution becomes vinegar.

HOCH₂(CHOH)₄4CH=O --> 2CH₃CH₂OH + 2CO₂

glucose --> ethanol

CH₃CH₂OH + CO₂ --> CH₃COOH + H₂O

ethanol --> acetic acid(vinegar)

OR

Whiskeys and brandies are distilled from fermentation solutions and have a much higher alcohol content -- 40-45%, or "80-90 proof." Enzyme catalysts are not active in solutions of such high alcohol concentration, and the alcohol is safe from reaction with oxygen.

For commercial chemical use, ethanol and other small alcohols are obtained from petroleum alkenes.

The simple alcohols, compounds that contain the hydroxyl as the main functional group, have higher boiling points and greater solubility in water than hydrocarbons or alkyl halides of comparable molecular weight. Both of these groups are due to the hydrogen bonding between -OH groups of the alcohol and of the alcohol with the water.

How to make your own NON ALCOHOLIC dragon fruit enzyme?
Ingredients
1 medium sized organic dragon fruit
500mL filtered water, boiled and cooled

Equipment
A 1-litre wide-mouth glass jar with lid
A 3-litre stainless steel pot

Method
1. Sterilise the glass jar and lid by putting water in and boiling over stove for a few minutes.
2. Remove from fire and air-dry.
3. Rinse and peel dragon fruit.
4. Transfer to mixing bowl.
5. Use a wooden pestle and crush the dragon fruit into tiny pieces.
6. Transfer to the sterilised glass jar.
7. Add the boiled and cooled water.
8. Cover with lid and screw tight.
9. Refrigerate for three days in the refrigerator.
10. Remove from the refrigerator and leave in a cool clean place for 2-3 days to culture the microorganism.
11. The liquid will taste sourish when the carbohydrate in the dragon fruit is transformed by the microorganism and developed naturally into beneficial acids which help strengthen the intestinal flora to improve digestion.
12. Take about 100mL two times a day before meal. Pulps can also be taken together.
13. Refrigerate the balance in the refrigerator.
14. Consume within 3-4 days for best result.

How about ALCOHOLIC ones??
just by using the ratio of 1:3:10
where the ratio means sugar:dragon fruit flesh:water
with the methods mentioned above.
AND!! leave it to ferment for a month

Here's the product of it. Well, about the bottle..replace "Bacardi" with "Dragon Fruit Enzyme Drink"

I just love the Bacardi logo

Benefits?
- improve digestion
- strengthen the immune function
- improve cell function
- discharge waste from the body
- improve skin condition
- prevent fungal and yeast growth

Enzyme, a protein

2009-06-07T09:07:00.000-07:00

ok ok..the real reason why I chose to write about this is that my mom has been making enzyme since last month after she read a news article about this. Since it's environmental friendly and pretty useful, she was quite supportive with that idea. I'm gonna point out some interesting chemical facts about enzymes and ways to make them. So, here goes:

ENZYMES

enzymes

This is what it says in the video:
"Enzymes enable molecules called substrates to undergo a chemical change to form new substances called products. Each enzyme acts on a specific molecule or a set of molecules called substrates. Each substrate fits into an area of the enzyme called the active site. This fitting together is often compared to a lock and key mechanism. However, the enzyme changes shape a little to fit with the substrate. In the enzyme-substrate complex, the enzyme holds the substrate or substrates in a position where a reaction can occur easily. After reaction, the enzyme releases the products and could go on to carry out the same reaction again and again."

Enzymes are the remarkably efficient biological catalysts responsible fot the thousands of reactions needed for the chemical processes of life.
All enzymes are proteins and can be classified as either:
1.Simple proteins whose catalytic activities rely only on the enzyme's polypeptidyl structure
2.Conjugated proteins which require a non-protein component(s) for activity

The non-protein components of enzymes, called cofactors, include metal ions and organic biomolecules(coenzymes) like B-vitamins. If a cofactor is tightly bound to an enzyme, it is called a prosthetic group.
An enzyme is classified by the type of reaction it catalyzes, and the six major classes of enzymes are:
oxido-reductase
transferases
hydrolases
lyases
isomerases
ligases

In an enzyme-catalyzed reaction, increasing the substrate concentration increases the reaction rate(v). However, after the active sites of the enzyme molecules are saturated with substrate, the reaction rate becomes independent of substrate concentration (zero-order reaction).

The maximal velocity rate theoretically attainable under these conditions is called Vmax. The substrate concentrationat which the reaction rate is half of that of Vmax is called the Km(Michaelis constant). Each enzyme displays characteristic Km for its substrate(s). The relationship among substrate concentration,v,Vmax,Km, and the initial reaction rate of an enzyme reaction is mathematically expressed in the Michaelis-Menten equation.
The Km and the Vmax values of an enzymatic reaction are often determined by plotting the reciprocals of [S] and v values(Lineweaver-Burk plot). Ideally, the Lineweaver-Burk plot yields a straight line with a slope equals to Km/Vmax, and the 1/v and 1/S intercepts are equal to 1/Vmax and -1/Km respectively.

Pretty confusing but the graph makes my life and yours(I hope) easier:

Three general types of inhibition of enzymatic activity are called competitive, non-competitive, and ~~irresistable~~ irreversible .

ok ok..enough of facts.
How to make garbage enzymes?

1. Use the ratio of 1:3:10 (sugar:vegetable/fruit dregs:water).
2. For the sugar component, use jaggery or molasses.
3. For a fresh-smelling enzyme, add orange, or lemon peels, or pandan leaves. (Vegetable waste will give an unpleasant smell).
4. Use an air-tight plastic container to allow expansion. Do not use glass or metal containers. Place the container in a cool, dry, and well-ventilated area. Avoid direct sunlight. Open the container daily in the first month to release gases.
5. If you have not gathered enough kitchen waste, you may fill the container gradually. The three-month fermentation process starts with your last batch of kitchen waste. Push the floating garbage down once in a while.
6. The enzyme liquid should be dark brown in colour. It it is blackish, add in the same amount of sugar to start the fermentation process again.
7. Ignore any white, black or brown layer that forms on the surface of the mixture. This is just yeast. If the container is not airtight, flies or maggots may appear. Leave them and the chemical reaction will resolve them naturally.
8. After 3 months, filter the fermented liquid through a sieve. Use the residues in your new batch of enzyme or as fertiliser.
9. The enzyme will never expire and must be diluted with water for use.

Here's a picture of the enzyme my mom made:

and another one..

References:
http://www.chemeddl.org/collections/netorials/biomolecules/enzymes/enzyme4.htm
http://dept.physics.upenn.edu/courses/gladney/mathphys/subsection4_1_7.html
7 April 2009, The Star newspaper

Pest-A-Side and Foods

2009-06-02T02:22:00.000-07:00

Pesticides

Contamination of food with residues of pesticides may result from the application of these chemicals in agriculture, industry or household. The number of organic pesticides in use is nearly 300 and this includes insecticides, miticides, nematocides, rodenticides, fungicides, and herbicides. The most likely compounds to appear as food contaminants are the insecticides of which there are two main classes, the chlorinated hydrocarbon insecticides and the organophosphorus insecticides.

Chlorinated Hydrocardon Insecticides

3 classes:
- oxygenated compounds
- benzenoid nonoxygenated compounds
- monoxygenated nonbenzoid compounds

2 properties:
- Stability which leads to persistence in the environment
- Solubility in fat which results in their deposition and accumulation in fatty tissues

Some structures:

Aldrin
is a technical compound containing about 95% of the compound 1,2,3,4,10,10-hexachloro-1,4,4a,5,8,8a-hexahydro-exo-1,4-endo,5,8-dimethananonaphthalene. It has a molecular weight of 365, formula C₁₂H₈Cl₆O and contains 58% chlorine. Residues of this compound are converted into dieldrin by epoxidation.

Dieldrin
contains about 85% of the compound 1,2,3,4,10,10-hexachloro-6,7-epoxy-1,4,4a,5,6,7,8,8a-octahydro-exo-1,4-endo-5,8-dimethanonaphthalene. Molecular weight 381, C₁₂H₈Cl₆, and contains 56% chlorine.

DDT
is a technical compound which contains about 70% of the active pp'-DDT.

Rhothane(TDE)

Endosulfane

Heptachlor
contains about 75% of 1,4,5,6,7,10,10-heptachloro-4,7,8,9-tetrahydro-4,7-methyleneindene, C₁₀H₅Cl₇, with molecular weight 373.5 and containing 67% chlorine. In animal and plant tissues it epodizes to heptachor epoxide, which is analogous in structure to HEOD (dieldrin).

Heptachlor Epoxide

In animal products, chlorinated hydrocarbon residues would be predominantly present in the lipid portion. Tn plant materials, the residue of chlorinated hydrocarbons would be mostly on the surface bound or absorbed by waxy materials but some can be translocated to inner parts.

Organophosphorus Insecticides
are inhibitors of chlorinesterase

Properties:
- Water soluble
- Volatile
creates less of a problem as food contaminants than the chlorinated hydrocarbons.

In animal products, organophosphates are present in both lipid and aqueous parts.

The organophosphorus insecticides may be subject to oxidation, hydrolysis and demethylation. Thiophosphates may be changed to sulfoxides and sulfones in animals and plants.

Extensive research has demonstrated that processing methods such as washing, blanching, heating and canning may remove large proportions of pesticide residues.
An example of the removal of DDT and Carbaryl from vegetables by washing, blanching and canning is shown below.

An Apple A Day

2009-05-30T03:57:00.000-07:00

Everyone has heard that "an apple a day keeps the doctor away," but have you ever wondered what this old saying really means?

It's not because of the apple's vitamin and mineral content. Apples contain some potassium, but only small amounts of other minerals and vitamins.

What is special about an apple then?
Bulk. In other words, fiber, the structural material that's found in all plants. Apples are an excellent source of dietary fibre.

Just for entertainment purposes :)

FIBER is not a nutrient in the classic sense, the way protein or vitamins and minerals are. It's not absorbed into the blood-stream for delivery to cells and tissues. Quite the reverse: most fiber is not digested by our bodies. Most of it is just passing through - and it takes other waste materials along with it.

How fiber works?
All foods that grow in fields or on trees and bushes contribute fiber - or what was once called "roughage" - to the diet. Foods of animal origin, meat and dairy products, do not. Nor do refined grain or certain types of fruit and vegetable products, because refining means the fiber has been removed.
In the case of wheat, refining removes the bran. In fruits and vegetables, refining may remove the pulp.
Fiber is not digested by our digestive enzymes. It's true that being chewed, fiber foods do release nutrients, various vitamins, and amino acids, depending on the food.
But the bulk remains..
One vital characteristic of fiber is its ability to bind water. Pectin, a kind of fiber in our daily apple, is especially good at this.
As fiber moves through the body, it absorbs water, thus growing softer and larger.

In the medical world..
Apple Fibre is a soluble type of fibre rich in pectin. These fibres are soluble (or gel-forming) that can absorb water from the digestive tract. This process helps to increase the size of the stool and normalise its transit time through the bowel. Soluble fibre can be beneficial in cases of constipation and diarrhoea. Having adequate fibre in the diet may also prevent a person from having certain diseases like diverticulosis, colon cancer, haemorrhoids and varicose veins.

When used as part of a calorie controlled diet, studies show that soluble fibre can enhance weight loss and enhance healthy bowel function. Soluble fibre helps to normalise the levels of fats in the blood stream. Research shows that approximately 10 gms of soluble fibre taken each day can have the effect of reducing total cholesterol by up to 4% in people with elevated cholesterol levels.

Think of the familiar form of fiber called sponge. As it swells with water, a sponge becomes softer and binds other materials to its surface.
That's how edible fibre works in the body, absorbing water and binding food residue.
The result is a soft, bulky stool.
This increases the frequency of bowel movements.

Milky-Reals

2009-05-15T08:09:00.000-07:00

my creation of that word is actually
Milk + Cereals

To be exact, Dutch Lady low fat milk and Nestle's Nestum cereal.

Healthy snacking.

Milk can be considered as containing three basic components; water, fat, and non-fatty solids(NFS) or solid-not-fat(SNF).
The really amazing fact about milk is that it's acidity can vary with different types of tests. Cow's milk is:
-acid to phenolphthalein
-alkaline to methyl orange
-amphoteric to litmus
due to presence of phosphates.
The pH is usually between 6.4 and 6.6.

Cereals carbohydrate protein protein carbohydrate protein carbohydrate protein fibre carbohydrate carbohydrate fat carbohydrate carbohydrate carbohydrate iron carbohydrate vitaminB1

Dear Brain, please start working.

2009-05-09T00:57:00.000-07:00

SOMNOLENCE
mental fatigue

5.07pm now.
No proper lunch. Only granola bars, hot chocolate, and more chocolate foods. Citrus oranges as well for now.
My brain's beginning to shut although I had 8 hours of sleep.
Maybe it's because of jet lag. (I was pretty nocturnal during the holidays)

Lacking of the transfer of neurotransmitters across the synapse in my brain probably had caused me to feel sooo sleepy.

GrrwLLL-er Day

2009-05-07T07:09:00.000-07:00

First lesson of the day, or should I say the ONLY lesson of the day started at 11.30am was Biology. My tummy vibrated and made growling noises like a mini earthquake.

HUNGRY

1.00pm - class ended.
Michelle, Pei Yee, Hasha, and I decided to get ALL our photostating done by today.
Waited for approximately an hour.
Gosh! I was almost starving!

I felt my stomach contracting.
The food I had a few hours ago had thoroughly churned and mixed with the gastric juice by peristaltic contractions of my stomach's wall. Eventually, chyme is formed.
Gastric juice accumulated gradually.

Moments later, I finally had something to munch on.
Wafer
along with water.

Lasted me for the next few hours before I got home.