Alcoholic drinks.................

There are 3 types of alcoholic drinks which are beer, wine and spirits (distilled beverage). All this alcoholic drinks contain ethanol, C₂H₅OH which is one type of alcohol.


Do you know how the brewers get the ethanol??The answer is ethanol can be obtained by using the yeast in fermentation and brewing of starches. Starches such as malted barley, rice and other cereal grains. And do you know what is the differences between the beer, wine and distilled beverage??I will write about the process of production of beer, wine and distilled beverage to show out the differences among them.

Production of Beer.

i)Milling

Milling is a process in which break the out layer of malt barley and break the malt starch also to let the enzyme to penetrate the starch more efficiently during the mashing process.

This is malted barley.


This is a milling machine.

ii)Mashing

Mashing is the process which mix the malted barley from milling with hot water to form a mash. During this, malt starch + malt enzyme -----> simple sugars

The mash temperature normally lies between 62^oC to 65^oC . This is the optimum temperature for amylase to breakdown the starch molecules into fermentable sugars such as glucose, maltose and maltotriose. This sugar then dissolve in the liquor surrounding the mash to form a sugary solution called wort. Then the wort will run off from the mash tun into work kettles.

iii)Wort boiling

This is a wort kettle.

Superheated water is pumped in the wort kettles. This water is kept at a high pressure so can be heated to a temperature of 135^oC. There are 3 reasons why should boil it vigorously. First, this can sterilise the wort completely to breakdown the enzymes. Secondly, boil it vigorous is important in the isomerism of alpha acid into isohumulones which impart bitterness to the beer. This is why the beer taste bitter. Hops have many functions such as balance the sweetness of the malt with bitterness, contributing a variety of desirable flavors and aromas and having an antibiotic effect to less desirable microorganisms in the activity of brewer's yeast. Degree of bitterness is depended on the degree of insoluble alpha acids are isomerized. Third, the proteins and tannins from the malt and hops are dissolved so that these components will not combine to form a complex which will cause a haze in cask, keg or bottle.
This is hops.

iv) Separation

Whirlpool separator is an upright cylindrical vessel with a dished base. In the whirlpool separator create a vortex in the liquid. During this separation, precipitated protein and tannin and hops are separated out from the wort.

v)Wort cooling

The temperature of the hot bitter wort is 90^oC, it passed through a paraflow or heat exchanger to make the temperature decrease and become 16^oC - 20^oC. Cold water is pumped in the opposite direction to the hot bitter wort and a thin sheet of stainless steel is separated both of the liquid and the heat exchange between the two liquids. The wort is cooled because 16^oC - 20^oC is the optimum temperature for yeast.

vi)Fermentation

The cooled wort is then flow into the fermenting vessel. This is where the yeast is added.
C₆H₁₂O₆ , Glucose + Yeast -----> 2C₂H₅OH , ethanol + 2CO₂ + energy

During fermentation, a thick head is formed on the surface of the fermenting beer. When fermentation is completed, the yeast is skimmed off and collected in a large trough. The fermented beer is remained in the fermenting vessel to allow a certain amount of maturation and settling of yeast left in suspension after skimming.

This is a yeast.

vii)Cask racking

The beer is filled into a cask then the casks are sealed with a plastic shive in the bung hole and stored in a cellar. Secondary fermentation is occurred in the cask to build up a pressure of CO₂ which this gas will dissolve into the beer and produce natural sparkle. The secondary fermentation is important because the excess CO₂ which produced from secondary fermentation has a cleansing effect on the beer by removing certain volatile flavours and aromas associated with freshly racked beer.

Production of Wine.

i) Harvest




During picking grapes to use in wine making process, harvest time is important. Grapes are havested either by hand or mechanically. Grapes that havested by hand can ensure that only the best grapes are havested and produced a good quality of wine.

ii) Crushing and de-stemming

Crushing is the process which squeezing the berries and breaking the skins of the grapes to start to liberate the content of the berries. White wine and red wine have differenced in destemming. When making white wine, the stem are placed in the press with the berries.The presence of stems allow juice to flow past flattened skins. When making red wines, stems of the grapes are removed because the stems contain a high tannin content which give the wine a vegetal aroma due to present of 2-methoxy 3-isopropylprazine. Tannin caused a dry and puckery feeling in the mouth after consume of red wine. Most red wine get the colour from the grape skins. Therefore, the grape skin is left to in contact with the grape juice. When crushing for white wine, it just need the grape juice and avoid to extract skins or grapeseeds.

iii) Fermentation

The grape juices are then put into the fermentation vats where alcoholic fermentation takes place. Yeast is then added to the fermentation vats.

sugar from grape juice + yeast-------> ethanol (l) + CO2 (g)

The phosphates from ATP are attached to the sugar and the six-carbon sugar molecules begin to split into three-carbon pieces and go through a rearrangemnt reaction (isomerism). During isomerism, the carboxylic carbon atom is released as carbon dioxide and the rest of the components become acetaldehyde. The absence of oxygen convert the acetaldehyde to ethanol. Some of the acetaldehyde will convert to acetic acid by oxidation. Carbon dioxide is visible in the bubbles form.

For red wines, the temperature during fermentation is 22^oC to 25^oC and for white wines, is in between 15^oC to 18 ^oC. When sugar content is too low for fermentation, sugar can be added by chaptalization. This fermentation turn grape juice into an alcoholic beverage.

Carbonic maceration is another type of fermentation which add yeast into the grape and fermentation takes place inside the individual grape berries.

iv) Ageing

The wine are then filled into stainless steel fermentation vessel or oak barrels kept under airlock to avoid wine from oxidation. ln the room that keep the stainless stell fermentation vessel must have a specific humidity, heat and light. If not, it will make the wine change its character.

Sparkling wine such as Champagne is a wine that have more carbon dioxide to make it fizzy and sugar added after the second fermentation to make it become sweeter.

Production of distilled beverage.

Distilled beverages contain higher concentration of alcohol which higher than 15%. Distilled beverages include brandy, vodka, whisky, gin, rum, tequila... Distilled beverages are produced by the same process as wine but then they need one more process which is distillation.

i)Brandy

Brandy is produced by distilling white wine. The white wine is distilled in a distilling vessel. The wine is heated then all alcohol evaporates while the percentage of water no change. The liquid that is obtained at the end of the distillation is a very pure, colourless, odourless and tasteless distilled liquid with an alcohol percentage of 96.5%. This distilled liquid is then mixed with the heated non-alcoholic wine until the percentage of alcohol around 40%.

ii) Vodka

Vodka contain a very high alcohol percentage which up to 40%-50%. Vodka is produced from grains instead of malted barley or grapes. The process of production by using grain is the same as the production of wine. The alcohol vapors are collected after distillation and it is dilluted with water until percentage of alcohol become 40%.

iii) Whiskey

Whiskey is smilar to vodka but then whiskey has one more process which vodka doesnt need. It is maturation. Whiskey can be continued from the vodka which mean vodka can be used to produced whiskey. The vodka is poured into wooden barrels for maturation so that more aromas are given to the whiskey. Whiskey has a lower percentage of alcohol than vodka.

iv)Rum

The production of rum is similar to the production process of brandy but then only the material that used is not the same. Rum use juice of a sugar cane or molasses. It undergoes a maturation and store from a year to several years.

v)Gin

The production of gin can be continued from the production process of vodka. Gin is added juniper berries and other herbs to the vodka. Gin need not maturation and after the production of gin, it is filled in bottles.

Effect of alcoholic beverages.

So next time must think before u drink. Dont consume it tooooooooooo much and dont think that they are "herbal tea".... And try to consume it only once in a while.

Detergent in our daily use

I think everyone tried before stained your lovely shirt with coffee and whatever that make your shirt dirty. And after you soak in the water with detergent, the stubborn stains and dirt disappear. Do you know what are they in your detergent to help you wash away the grease, oil and dirt? And how the detergent and soap wash way the grease?

+ →

Detergent

Detergent is a salt that formed from neutralization between alkyl hydrogen sulphate and an alkali. The most effective detergent is Sodium Lauryl Sulphate, C₁₂H₂₅NaO₄S.

First process involve the production of lauryl hydrogen sulphate,

lauryl alcohol, CH₃(CH₂)₉CH₂OH + sulphuric acid, H₂SO₄→ lauryl hydrogen sulphate, CH₃(CH₂)₉CH₂OSO₃H + H₂O

Second process involve the neutralisation of lauryl hydrogen sulphate,

lauryl hydrogen sulphate, CH₃(CH₂)₉CH₂OSO₃H + sodium hydroxide, NaOH → sodium lauryl sulphate, CH₃(CH₂)₉CH₂OSO₃Na + H₂O

The chemistry structure in the above is sodium lauryl sulphate, the circle part is polar end which is negatively charged and it is hydrophilic which attract water. The tail part is non-polar end and has no charge. It is hydrophobic which repel water. The pictures below show how the detergent remove the grease on the shirt.

First, the hydrophobic tail of the anion part dissolves in the grease which is shown as brown colour, the hydrophilic part dissolves in the water.

After that, the grease started to loosen and lift off from the surface of the shirt . Therefore, rubbing and scrubbing help to faster the loosen of the grease from the surface of the shirt.

The grease is surrounded by the anion part and the grease is total lifted off from the surface of the shirt and suspended in water.

Besides that, there are many substances added into the detergent. For example, surfactant, biological enzymes, water softener and optical brightener.

Surfactant is added to keep oil and water from forming into layers. Surfactant have a hydrophilic side and hydrophobic side. The hydrophobic side stick to the oil or grease and hydrophilic side stick to the water. Surfactant also lower the surface tension of the water to allow detergent to wet surface and penetrate into, under, and around the grease.

Biological enzymes are the enzymes that digest protein, fats and carbohydrate on the shirt so it make the stain on your shirt disappear. For example, amylase digest starch stain, lipases digest oil stain and protease digest protein stain.

Optical brightener are used to enhance the appearance of the colour of shirt. Optical brighteners absorb ultraviolet radiation and re-emit the blue light and reduce the yellow colour of the shirt and make it become whiter. For example, fluorescent. Fluorescent contain phosphor which is the substance that emits visible light in response to some sort of radiation. A phosphor converts the energy in the UV radiation from a black light into visible light.

Water softener is used to reduce the calcium ions and magnesium ions in the hard water and make reduce the formed of the scum. Water softener based on the ion exchange principle which the calcium ions and magnesium ions are exchanged for sodium or potassium ions to make the water softer and give it a smoother feeling. Examples of the water softening are potassium chloride and sodium chloride.

How tha scum is formed on the shirt?

Scum normally is formed by using soap because soap contains salt such as Sodium stearate and Sodium palmitate , when calcium ions and magnesium ions in hard water mix with it, a insoluble salt is form which is Calcium stearate / Calcium palmitate.

Ca2+ (aq) + 2C₁₇H₃₅COO-(aq) ----> 2C₁₇H₃₅COOCa(s)

Of course, different detergent companies have their own "formula" in making their detergents. The chemicals that i introduce in the above are only some common and important ingredients in detergent.

Hope you enjoy the details of the detergent.