Lager. Beers made with yeast that settle on the bottom the container used. Thus, all the yeast and other material settles on the bottom which results in a clear beer. Most American beers are lagers.
Pilsner. A colourless lager beer originally brewed in the city of Pilsen. Water used for this style of beer tend to be harder, with a higher calcium and magnesium content than water used for lager. The colour of pilsner is also lighter than that of lager beer.
Extent of alcohol concentration of different beers and its effect on drinking one of them
Alcohol is a common addictive substance. Almost every organ system is affected negatively by the excessive ingestion of alcohol, but none more seriously than the nervous system. Two experiments were conducted, in experiment one 2 beers were investigated, lager and pilsner for a period of 6 hours with the aim to evaluate the alcohol concentration of different types of beer and the effects of drinking one of them on the cns.
in experiment 2, twenty people were tested for a period of 4 hours to evaluate reaction time on individuals before and after consuming alcohol. The results in experiment one indicated that a higher concentration of ethanol concentration was found in beer lager when compared to beer pilsner. The ph. of lager was low than pilsner which indicated that beer larger was more acidic than pilsner. Beer lager showed the highest number of yeast cells when compared to pilsner, indicating that that there is high ethanol concentration percentage, this destroys brain cells, as well as depresses the central nervous system. Experiment 2 indicated that it took longer to press the button for people after consuming alcohol than before alcohol consumption indicating that the alcohol had affected them. The reaction time was longer on a person who drank the beer with more ethanol percentage. Reaction time was longer because their mind or vision was disturbed, drinking alcohol over a prolonged period of time can cause serious problems with learning and memory. Ethanol might have interacted with their brain receptors, interfering with the communication between nerve cells.
Key: Alcohol, Ethanol concentration, brain, central nervous system, receptors.
The alcohol found in beverages such as beer is chemically classified as ethanol. Ethanol is made up of a chain of two carbons and a hydroxyl group(Costardi,J.V. V,et al,2015)Alcohol is one of the most widely used of all industrial solvents,it is produced with aid of continuous fermentation. The concentration of alcohol selection varies, considering the influence that it can either be useful or dangerous to human health. Alcohol can easily cross membrane barriers and reach different parts of the body very quickly. Alcohol can affect several parts of the brain, but in general contracts brain tissues, destroys brain cells, as well as depresses the central nervous system. Excessive drinking over a prolonged period of time can cause serious problems with learning and memory. Ethanol interacts with the brain receptors, interfering with the communication between nerve cells, and withhold excitatory nerve pathway activities(Davies, Martin,2003).The effect can be both direct or indirect. Difficulties in problem-solving and abstraction (MA Schuckit, 2006).
Beer, the complex brewed beverage made from yeast, hops, water, malt. Yeast is a fungus that feeds on sugar to create energy for itself through anaerobic respiration to create its energy. The by-products of anaerobic respiration are ethanol (alcohol) and CO2. This production of alcohol via yeast is called fermentation.The aim of the study was to evaluate the ethanol concentration of various beers and their impact on Cns and also assess the reaction time of individuals before and after alcohol consumption. Although there has been a lot of research in the relevant fields. Studies concerned with effects of alcohol were concerned mainly with learning and not memory. This study is more focused on the behaviour of human brain of individuals after consuming alcohol. The study intends to create public alertness by providing data about the behavioural changes that alcohol can bring into an individual after consumption. The objectives of the study was to describe the effects of alcohol on the CNS and to also determine the behavioural changes on human beings after consumption of alcohol.
Beer is one among the foremost normally consumed alcoholic beverages with effects on human health. Within the study it was generally recognized that the effect of a given dose of alcohol had an effect on the central nervous system, they varied wide from one individual to another. The actions of alcohol on the central nervous system resulted in a general impact of logical reasoning and motor incoordination (Berman MO, Shagrin B, Evert DL, Epstein C, 1997),for this reason the reaction time in experiment 2 took longer to press the button after consuming alcohol indicating that alcohol does have an effect within the reasoning of a person.it may result in behavioural effects which incorporates, loss of executive function, and cognitive deficit.behavioral effects is attributed to the ability of ethanol to activate multiple neural pathways and how one responds to alcohol.
From the study it can be identified which beer was drank by individuals.
Table 1: beer lager
time(hour) ph. number of yeast cells(cfu/ml) ethanol concentration%
1 7 1000 0
2 7 1500 1
3 6,5 2000 5
4 6 4000 11
5 5 6000 16
6 4,5 7000 20
Table 2:beer pilsner
time(hour) ph. number of yeast cells (cfu/ml) Ethanol concentration (%)
1 7 1000 0
2 7 1100 1
3 7 1500 2
4 6,5 2000 4
5 6 3000 8
6 5,7 3500 10
Figure 1: reaction time before and after consumption of alcohol
Series 1: reaction time before consuming alcohol/million seconds
Series 2: reaction time after consuming alcohol/million seconds
Table 3: descriptive statistics of reaction time before and after consuming alcohol
Reaction time before consuming alcohol Reaction time after consuming alcohol
Mean 240 Mean 280
Standard Error 7,658844217 Standard Error 8,339822
Median 237,5 Median 274,5
Mode 225 Mode #N/A
Standard Deviation 34,2513926 Standard Deviation 37,29682
Sample Variance 1173,157895 Sample Variance 1391,053
Kurtosis 0,159412825 Kurtosis -0,79799
Skewness 0,474853498 Skewness 0,197737
Range 130 Range 130
Minimum 180 Minimum 220
Maximum 310 Maximum 350
Sum 4800 Sum 5600
Count 20 Count 20
In experiment one the data recorded was the extent of fermentation on different beer, Ethanol is a product of fermentation, the higher the concentration of ethanol the more the extent or longer fermentation has occurred. High ethanol concentration means low ph. and low ph. will result in acidic solution. Both beers had a six hour fermentation period. Table 1 shows that beer lager had the highest number of yeast cells when compared to beer pilsner, also there was high ethanol concentration percentage, there was a low ph. which resulted in beer lager being more acidic. Table 2 shows beer pilsner with low number of yeast cells when compared to beer lager, low ethanol concentration and high ph. causing the beer not to be too acidic.it concludes that beer lager had the highest ethanol concentration percentage when compared to pilsner, they can both cause an effect on the cns but beer lager will have more effect than pilsner because of the high ethanol concentration.
experiment 2 was evaluating the effect of the beer on people after drinking and their reaction time after consuming alcohol, if a person takes too much longer to press the button when the colour changed it means that the alcohol has affected them if they dont take too much time to press the button the alcohol might not have affected them.20 people were tested for this experiment for a period of 4 hours. Figure one indicates that it takes longer to press the button for people after consuming alcohol than before, table 3 also shows that the mean of reaction time after consuming alcohol is higher than before alcohol consumption indicating that the alcohol might have affected them. The reaction time is longer on a person who might have drank the beer with more ethanol percentage. Reaction time might be longer because their mind or vision is disturbed or they are slow to react because the beer has affected their central nervous system as alcohol is known to affect the central nervous system of a human being.
The study had potential limitations, there were threats to the validity of this study with factors associated with the participants. The process concerned within the choice of participants to be involved during the study and therefore the type of group selected might have influenced the results obtained, so the validity might have been compromised.
To record the extent of fermentation of the different types of beer out experiment 1 was carried out, a ph. meter was used to measure ph. A calibrated hygrometer was used to measure ethanol concentration, the hygrometer was used during the pre-fermentation and post-fermentation phase to determine the potential alcohol content, and this was done for a period of 6 hours. The results were recorded after measurements.
In second experiment, 20 people were tested before and after consuming the Pilsner beer for a period of 4 hours to check out the reaction time of individuals before and after consuming the alcohol. The person being tested looked at a coloured block on a computer screen.as soon as the colour changed, they pressed a button. The time taken to press the button was recorded by the computer before and after consumption of alcohol. The data obtained was recorded on the excel programme and analysed using analysis tool pak from excel programme. Descriptive statistics was recorded for the purpose of numerical data.
Alcohol is the most frequently consumed toxic substance in the world. Alcoholism and alcohol abuse remain a significant health problem and represents the third leading cause of preventable death.
Department of Life Sciences Central University of Technology Bloemfontein South Africa
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