Why do onions make us cry?

Do you all guys wonder why this thing does happen and how? I don really cook at home, but sometimes I do help my mom to cut some cooking stuff. Especially onion, which I don like to cut because it makes me cry... Does this thing happen to you all guys too...? I mean crying while cutting onions...

When you slice through an onion, you also cut through the onion cells. When the cells are cut, enzymes which are normally inside the cell are released. One of these enzymes, alliinase (from the onion), then reacts with a sulphur-containing compound known as ‘Prensco', that is also released by cutting the cells. This reaction results in the formation of 1-propenylsulphenic acid, which is further converted by the LF-synthase enzyme to propanethial S-oxide gas. This gas is also known as the Lachrymatory Factor (‘crying factor'), which also explains the name of the enzyme LF-synthase (meaning Lachrymatory Factor synthesising enzyme) 

This gas is instable and can react with water which results in, among others, sulphuric acid. When this happens in the eye, the eyes start to neutralise the acid by producing large amounts of water, and thus make us cry.

Many people start rubbing the eyes, which often works contra-productive if you just cut onions, as most likely your hands are covered with onion juice. Rubbing thus will make the irritation worse. 

How to chop onions without tears???

As a general rule, move your head as far away from the onion as you can, so the gas will mostly disperse before it reaches your eyes. 

Keeping the onion wet, or cutting under water is very effective, as the gas immediately reacts with the water around the onion and never reaches the eyes. 

Glasses and goggles also prevent the gas to penetrate the eyes to some degree, goggles being the most effective (although not practical). 

Cooling the onion may also help, as the enzyme activity is much slower at low temperatures. Cooking destroys the enzyme. 

Do you all know what is in coffee???

Coffee makes our morning fresh and energetic. The reason? Caffeine...

Caffeine is a central nervous system stimulant. It's one of the most popular drugs in the world, consumed by up to 90% of people in the world in one form or another, but mostly in beverages.

It is a naturally occurring substance found in plants like cocoa beans, tea leaves, and kola nuts.

Caffeine is a stimulant of the central nervous system (CNS), the cardiac muscle -increases heart rate, and respiratory system -relaxes air passages permitting improved breathing, and allows some muscles to contract more easily. It acts as a diuretic it increases the rate of bodily urine excretion, and delays fatigue -having the effect of warding off drowsiness and restoring alertness. Caffeine is probably the most popular drug in use because of these reasons. The effects that we might notice after consuming a large cup of coffee are hands getting cold, muscles tensing up, feeling of excitement and increased heart beat.

Effects of Caffeine

Caffeine absorption occurs in the body very quickly. It enters the bloodstream through the stomach and small intestine, and its effects are felt as soon as 15 minutes after consumption. It is completely absorbed within 45 minutes of ingestion. Caffeine does not accumulate in the bloodstream no is it stored in the body, but it does persist but only about ½ is eliminated in the urine within 6 hours. 

Caffeine sensitivity refers to the amount of caffeine that will produce negative side effects in a particular person. Regular caffeine consumption reduces sensitivity to caffeine, and a higher intake is needed for the same effects. So caffeine is considered to be an addictive drug. 

When we try to reduce caffeine intake, the body then becomes oversensitive to a chemical in the brain (adenosine) relevant to the sleep process, causing blood pressure to dropdramatically, producing an excess of blood in the head area (not necessarily on the brain), and leading to a headache often lasting several days. Other withdrawal symptoms reported are fatigue and muscle pain, irritability, inability to work, nervousness, restlessness, and feeling sleepy, and in extreme cases, nausea and vomiting. 

Cigarettes

Smokes don’t think about the chemical in the cigarettes. They only think about how cigarettes help them cope with the stress of daily life, how cigarettes calm them down when they we're angry, help them relax at the end of a long day, comfort them when they were sad or lonely. But do they know that there are harmful chemical in cigarettes???

When the chemicals in cigarettes are inhaled, they put our bodies into a state of physical stress by sending literally thousands of poisons, toxic metals and carcinogens coursing through our bloodstream with every puff we take. And those chemicals affect everything from blood pressure and pulse rate to the health of our organs and immune system. Most of the lung cancer related deaths are due to smoking. We do know that air tainted with cigarette smoke is dangerous for anyone who breathes it whether they are smoker or not.

Let's we look at some of the harmful chemicals in cigarettes and how does they affect our health.

The main ingredient in a cigarette is tobacco. Tobacco is a harmful substance. Chemicals and preservatives are added to the tobacco and filled into the cigarette. According to a recent study there are more than 3000 chemicals in the cigarette smoke. Worldwide smoking by teens has increased rapidly.

Carcinogens

A carcinogen is defined as any substance that can cause or aggravate cancer. Approximately 60 of the chemicals in cigarettes are known to cause cancer.

TSNAs

Tobacco-specific N-nitrosamines (TSNAs) are known to be some of the most potent carcinogens present in smokeless tobacco, snuff and tobacco smoke.

Benzene

Benzene can be found in pesticides and gasoline. It is present in high levels in cigarette smoke and accounts for half of all human exposure to this hazardous chemical.

Pesticides

Pesticides are used on our lawns and gardens, and inhaled into our lungs via cigarette smoke.

Formaldehyde

Formaldehyde is a chemical used to preserve dead bodies, and is responsible for some of the nose, throat and eye irritation smokers experience when breathing in cigarette smoke.

Toxic Metals

Toxic / heavy metals are metals and metal compounds that have the potential to harm our health when absorbed or inhaled. In very small amounts, some of these metals support life, but when taken in large amounts, can become toxic.

Arsenic

Commonly used in rat poison, arsenic finds its way into cigarette smoke through some of the pesticides that are used in tobacco farming.

Cadmium
Cadmium is a toxic heavy metal that is used in batteries. Smokers typically have twice as much cadmium in their bodies as non-smokers.

Poisons

Poison is defined as any substance that, when introduced to a living organism, causes severe physical distress or death. Science has discovered approximately 200 poisonous gases in cigarette smoke.


Ammonia

Ammonia compounds are commonly used in cleaning products and fertilizers. Ammonia is also used to boost the impact of nicotine in manufactured cigarettes.

Carbon Monoxide

Carbon monoxide is present in car exhaust and is lethal in very large amounts. Cigarette smoke can contain high levels of carbon monoxide.

Hydrogen Cyanide
Hydrogen cyanide was used to kill people in the gas chambers in Nazi Germany during World War II. It can be found in cigarette smoke.

Nicotine

Nicotine is a poison used in pesticides and is the addictive element in cigarettes.


This is only a partial list. Recent breaks in the wall of secrecy have revealed that cigarettes are only about 40% tobacco, and 60% other junk. So smokes please stop smoking, because it is very bad for health.

People are dying every year because of cigarettes...

How does soap and detergents work???

We use soap and detergents frequently in our daily life. We use them to wash our hands & body and to clean our clothes without knowing how this thing does really work...

Soaps and detergents are very similar in their chemical properties. However, there is a significant difference between them, which soaps are produced from natural products, and detergents are synthetic, or man-made.

Detergents and soaps are used for cleaning because pure water can't remove oily, organic soiling. Soap cleans by acting as an emulsifier. Basically, soap allows oil and water to mix so that oily grime can be removed during rinsing. Detergents were developed in response to the shortage of the animal and vegetable fats used to make soap during World War I and World War II. Detergents are primarily surfactants, which could be produced easily from petrochemicals. Surfactants lower the surface tension of water, essentially making it 'wetter' so that it is less likely to stick to itself and more likely to interact with oil and grease. 

Modern detergents contain more than surfactants. Cleaning products may also contain enzymes to degrade protein-based stains, bleaches to de-colour stains and add power to cleaning agents, and blue dyes to counter yellowing. Like soaps, detergents have hydrophobic or water-hating molecular chains and hydrophilic or water-loving components. The hydrophobic hydrocarbons are repelled by water, but are attracted to oil and grease. The hydrophilic end of the same molecule means that one end of the molecule will be attracted to water, while the other side is binding to oil. Neither detergents nor soap accomplish anything except binding to the soil until some mechanical energy or agitation is added into the equation. Swishing the soapy water around allows the soap or detergent to pull the grime away from clothes or dishes and into the larger pool of rinse water. Rinsing washes the detergent and soil away. Warm or hot water melts fats and oils so that it is easier for the soap or detergent to dissolve the soil and pull it away into the rinse water. Detergents are similar to soap, but they are less likely to form films (soap scum) and are not as affected by the presence of minerals in water (hard water). 

Modern detergents may be made from petrochemicals or from oleochemicals derived from plants and animals. Alkalis and oxidizing agents are also chemicals found in the detergents. 

Petrochemicals/Oleochemicals

These fats and oils are hydrocarbon chains which are attracted to the oily and greasy grime.

Oxidizers

Sulfur trioxide, ethylene oxide, and sulfuric acid are among the molecules used to produce the hydrophilic component of surfactants. Oxidizers provide an energy source for chemical reactions. These highly reactive compounds also act as bleaches.

Alkalis

Sodium and potassium hydroxide are used in detergents even as they are used in soap making. They provide positively charged ions to promote chemical reactions.

Types of detergent 

Synthetic detergents have similar molecular structures and properties as soap. Although the cleansing action is similar, the detergents do not react as readily with hard water ions of calcium and magnesium. Detergent molecular structures consist of a long hydrocarbon chain and a water soluble ionic group. Most detergents have a negative ionic group and are called anionic detergents. The majority are alky sulfates. Others are "surfactants" (from surface active agents) which are generally known as alkyl benzene sulfonates.

Anionic Detergents

Cationic Detergents

Another class of detergents have a positive ionic charge and are called "cationic" detergents. In addition to being good cleansing agents, they also possess germicidal properties which make them useful in hospitals. Most of these detergents are derivatives of ammonia.

A cationic detergent is most likely to be found in a shampoo or clothes "rinse". The purpose is to neutralize the static electrical charges from residual anionic (negative ions) detergent molecules. Since the negative charges repel each other, the positive cationic detergent neutralizes this charge.
It even works because the ammonium (+1) nitrogen is buried under the methyl groups as can be seen in the space filling model.

Neutral or non-ionic detergents

Nonionic detergents are used in dish washing liquids. Since the detergent does not have any ionic groups, it does not react with hard water ions. In addition, nonionic detergents foam less than ionic detergents. The detergent molecules must have some polar parts to provide the necessary water solubility.

On the above graphic, the polar part of the molecule consists of three alcohol groups and an ester group. The non-polar part is the usual long hydrocarbon chain.

Bile Salts - Intestinal Natural Detergents

Bile acids are produced in the liver and secreted in the intestine via the gall bladder. Bile acids are oxidation products of cholesterol. First the cholesterol is converted to the trihydroxy derivative containing three alcohol groups. The end of the alkane chain at C # 17 is converted into an acid, and finally the amino acid, glycine is bonded through an amide bond. The acid group on the glycine is converted to a salt. The bile salt is called sodiumglycoholate. Another salt can be made with a chemical called taurine.

The main function of bile salts is to act as a soap or detergent in the digestive processes. The major action of a bile salt is to emulsify fats and oils into smaller droplets. The various enzymes can then break down the fats and oils.

Soap

Soaps are sodium or potassium fatty acids salts, produced from the hydrolysis of fats in a chemical reaction called saponification. Each soap molecule has a long hydrocarbon chain, sometimes called its 'tail', with a carboxylate 'head'. In water, the sodium or potassium ions float free, leaving a negatively-charged head. 

Soap is an excellent cleanser because of its ability to act as an emulsifying agent. An emulsifier is capable of dispersing one liquid into another immiscible liquid. This means that while oil (which attracts dirt) doesn't naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed.

The organic part of a natural soap is a negatively-charged, polar molecule. Its hydrophilic (water-loving) carboxylate group (-CO2) interacts with water molecules via ion-dipole interactions and hydrogen bonding. The hydrophobic (water-fearing) part of a soap molecule, its long, nonpolar hydrocarbon chain, does not interact with water molecules. The hydrocarbon chains are attracted to each other by dispersion forces and cluster together, forming structures called micelles. In these micelles, the carboxylate groups form a negatively-charged spherical surface, with the hydrocarbon chains inside the sphere. Because they are negatively charged, soap micelles repel each other and remain dispersed in water.



Grease and oil are nonpolar and insoluble in water. When soap and soiling oils are mixed, the nonpolar hydrocarbon portion of the micelles break up the nonpolar oil molecules. A different type of micelle then forms, with nonpolar soiling molecules in the center. Thus, grease and oil and the 'dirt' attached to them are caught inside the micelle and can be rinsed away. 

Although soaps are excellent cleansers, they do have disadvantages. As salts of weak acids, they are converted by mineral acids into free fatty acids:

CH3(CH2)16CO2-Na+ + HCl ----> CH3(CH2)16CO2H + Na+ + Cl-

These fatty acids are less soluble than the sodium or potassium salts and form a precipitate or soap scum. Because of this, soaps are ineffective in acidic water. Also, soaps form insoluble salts in hard water, such as water containing magnesium, calcium, or iron. 

2 CH3(CH2)16CO2-Na+ + Mg2+ ----> [CH3(CH2)16CO2-]2Mg2+ + 2 Na+

The insoluble salts form bathtub rings, leave films that reduce hair luster, and gray/roughen textiles after repeated washings. Synthetic detergents, however, may be soluble in both acidic and alkaline solutions and don't form insoluble precipitate in hard water. 

What helps keep our teeth clean?

We all brush our teeth daily. But do you all know the important of brushing your teeth with toothpaste??? 

 

Toothpaste is a paste or gel dentifrice used with toothbrush. Toothpaste and a correct brushing action work to remove plaque, a sticky, harmful film of bacteria that grows on your teeth that causes caries, gum disease, and eventual tooth loss if not controlled. Toothpaste contains fluoride, which makes the entire tooth structure more resistant to decay and promotes remineralisation, which aids in repairing early decay before the damage can even be seen. Special ingredients in the dentifrice help to clean and polish the teeth and remove stains over time and toothpaste also help freshen breath and leave your mouth with a clean feeling.

Do we really concern about the ingredient of the toothpaste that we use in our daily life??? Do we??? Next time when you go to brush your teeth, take a good look at the label on the toothpaste. If you're like most people, you know your toothpaste contains fluoride. But take a good long look at the inactive ingredients. While you may find one active ingredient, you may find a dozen or more inactive ingredients on your toothpaste.

We all know the active ingredient in toothpaste typically its sodium fluoride. But sodium fluoride makes up less than one percent of toothpaste ingredients. What's the other 99% of toothpaste made up of? If most of what goes into toothpaste is labelled as inactive ingredients, why are these chemicals there? And what exactly are you putting in your mouth? The answers may surprise you.

Active Ingredients
Active ingredients are the chemically active portion of a product that works to relieve your symptoms. In toothpaste the active ingredients are what help to protect and strengthen your teeth. However, different toothpastes contain different functions, and thus may have differing active ingredients. For example, while ordinary toothpaste may only contain sodium fluoride as an active ingredient, tartar control toothpaste may also contain triclosan as an anti-gingivitis agent.

Sodium Flouride
A typical percentage of sodium fluoride found in toothpaste is 24%. Sodium fluoride is thought to strengthen teeth through the formation of flouroapatite, a component of tooth enamel. Besides toothpaste, sodium fluoride was used in the production of ceramics and rat poison. Hah???

Triclosan
Triclosan is an antibacterial and antifungal organic compound found in many antibacterial soaps, deodorants, acne medications, and other antibacterial applications. Some studies have shown that the popular Microban treatment you can find embedded into any number of hard surfaces contains Triclosan.

Inactive Ingredients
Okay, now we see what's the other 99% of stuff you put in your mouth when brushing your teeth?

Hydrated Silica
This is the abrasive used to polish and scrub the surface of your teeth in gel toothpastes. If you dry out hydrated silica you get the common silica gel found inside pepperoni packages and electronics. Silica gel absorbs water, so it is placed in little packets (coincidentally labelled, "Do Not Eat") inside packages of electronics and other items susceptible to damage from high humidity or water condensation. The water absorbing ability of silica gel also makes it a perfect ingredient for cat litter.

Sorbitol
After water, this is one of the top ingredients in children's toothpastes and is one of the main ingredients in adult toothpastes as well. So why is sorbitol more prevalent in children's toothpaste? Sorbitol is a form of most children's favourite ingredient sugar. Also known as glucitol, sorbitol is formed by reducing glucose into a form called sugar alcohol that retains 60% of sugar's sweetness with one-third the calories.
Sorbitol's use in toothpaste is three-fold. As a sweetener, it makes gives toothpaste a pleasant taste. It's also humectants, helping toothpaste stay moist. As an emulsifier, sorbitol works to keep the ingredients in toothpaste from "shifting". Ever notice that you don't have to shake a tube of toothpaste to mix it up? An emulsifier keeps the ingredients mixed up. Sorbitol was the ingredient that prompted this article. I noticed it was the main ingredient in light pancake syrup just shortly after noticing in children's toothpaste listed sorbitol as a primary ingredient. So children's is brushing their teeth with pancake syrup? Sorbitol is also used in sugar free mints, diet drinks, light pancake syrup (obviously) and as a skin softener in some soaps.

Glycerine
Another sugar alcohol used as a sweetener and humectants, glycerine makes toothpaste sweeter and smoother. It's found in a variety of products including cough syrup, shaving cream, and hair care products. In other forms glycerine is used to manufacture margarine and nitro-glycerine.

PVM/MA Copolymer
PVM/MA copolymer is a water fixative found in hairspray that does a wonderful job of making triclosan stick to your oral tissues longer. In other words, it helps triclosan stay on your teeth and gums where it can kill bacteria, rather than getting rinsed away.

Sodium Laurel Sulfate
You can find this detergent in just about any soap or shampoo (or toothpaste) that creates lots of suds. When you brush your teeth and the foam starts to appear, you can thank sodium laurel sulfate (SLS). Some studies link SLS to mouth ulcers.

PEG-12 (Dimethicone Copolyol)
This is a water-soluble polyether-modified silicone commonly used in hair conditioners.

Tetrasodium pyrophosphate
Used as a buffering and thickening agent in a variety of foods including marshmallows, pudding, chicken nuggets, and soy-based meat alternatives. It's a mildly toxic clear compound that acts as a tartar control compound by removing calcium and magnesium from teeth. It is occasionally found in household detergents to remove these minerals from clothing as well.

Cocamidopropyl Betaine
This is a special kind of detergent that acts as an acid or a base. It is non-irritating cleanser used in shampoos and its anti-static properties are used in conditioners. In its pure form it is a pale yellow liquid.

Propylene Glycol
Other humectants used to keep toothpaste from drying out, propylene glycol is the main ingredient in many shampoos, deodorants and hair dye. It's also used in smoke machines to make fake smoke and as an ingredient in deicing fluid for airplanes.

Cellulose Gum
This chemically inert thickener is used to help maintain toothpaste texture.

Titanium Dioxide
Typically used to colour your toothpaste a brilliant white, titanium dioxide is also used provide opacity. It can also be found in sunscreens, paint, plastics and pills.

Carrageenan
This is another thickener and stabilizer used in toothpaste. Carrageenan has the unique ability to thin out under stress and then bounce back when the stress is no longer applied. In other words, they help make toothpaste easy to squeeze out of the tube, but help it stiffen back up on the toothbrush. This ingredient comes from seaweed and is used in dozens of applications from air-freshener gels to processed meats and ice cream.

FD&C Blue Number 1
This synthetic dye is made from coal tar and is used to colour toothpaste, soap, shampoo and food. It's estimated that the average American consumes 16 mg of this dye a day.

Obviously not all toothpaste manufacturers’ use the exact same ingredients, but these are the main ingredients used in most toothpastes and a surprising number of other personal hygiene products. So whether you are using Colgate, Crest, Aquafresh, Rembrandt or whatever your favourite toothpaste happens to be, take a look at the inactive ingredients and check out exactly you're putting in your mouth the results may surprise you.