Excursion Report

The bus left around 9:30am, and when we reached, we were met by the safety personnel who took us through the whole security and safety procedures that are in place at the plant. Before going into the main plant, we were suited up in safety apparel (that is, the Personal Protective Equipment, PPE) and earplugs to prevent damage to our ears coming from the noise of the machines.

The next place we were taken to was the packaging area where the goods are properly packaged. The bottles and crates and all other items used in packaging are thoroughly washed before use to ensure that proper hygiene is maintained. Also before the goods are sealed, they are pasteurized

;the reason being tokill the microorganisms that might be present. After that, we were taken to the storage area where the finished products are kept; the goods are stored on top of pallets to prevent contamination from the ground.

Next, we were taken to the production area where the main work is done. We saw the adjunct cooker, where other carbohydrate sources are cooked (barley is the main source of carbohydrate but it is usually expensive; that is why adjuncts are used). The adjuncts can be maize, sorghum, rice, millet, etc. depending on the brand of beer. The barley malt and the adjuncts are acted upon by the enzyme, α-amylase which breaks down the complex bonds of the carbohydrate, releasing the glucose for the microorganism toact on. An example of type of α-amylase used is High Tempase, which is an α-amylase that can withstand high temperature.

After that, we saw the mash filter where the wort separation occurs; a process that also includes filtration. After the filtration, the spent grains are taken away, which can be used for animal feed. The product goes into the holding vessel where the product is stored (this step is optional). Then the we saw the wort kettle in which the wort is boiled.

After that, we saw the whirlpool tank where clarification takes place. In this place, the basic process is only sedimentation of the hops. Then the product (brew) is cooled in the wort cooler, then to the fermentation tank. As it passes through the wort cooler to the fermenter (fermentation tank), oxygen is added because the yeast that does the fermentation needs O2 at this point. Also, at this point, yeast is added too. During fermentation, the simple sugar is broken down toethanol and carbon (IV) oxide.

C6H12O6 + 2ADP + 2Pi –› 2C2H5OH + 2CO2 +2H2O

If care is not taken, during fermentation, off flavours can be produced, which can be esters. The cause can be a deviation from the optimal conditions of temperature and pH, and also allowing the yeast to overstay in the product. The time for the fermentation process is brand-dependent. It can be from 7-21 days. After the fermentation, the yeast will be removed; then a process called racking takes place, which is the transfer of the product from the fermenter to the storage tank. The yeast can be reused depending on the viability and consistency of the yeast. The type of fermentation used here is the bottom fermentation process.

The final section we were taken to was the BTS, the Biological Treatment System, which is also the Effluent Treatment Plant or the Waste Water Treatment Plant in some other factories. This is where all the waste water from the various production processes are treated. The aim of this treatment process is to protect the environment from harm. There is the aerobic plant and the anaerobic plant; the aimis to generate biogas which is also used to power various production processes. Water is treated to reduce the COD, Chemical Oxygen Demand of it. A high COD means that the oxygen from the environment will be used to reduce its COD, which adversely affects the environment. This happens in the aerobic plant. In the anaerobic plant, further reduction of the COD content of the water also happens. There are also a number of tests and analyses carried out to ensure that the water released into the environment is as safe as possible. These tests include checking the COD content, checking for ions like nitrates. After the water has been treated, the waste produced is called the sludge which can be processed to give fertilizer.

Also, biogas is produced here, mainly methane using autolyzed yeast (i.e. yeast that has been killed by high temperature). Microorganisms are used to produce the biogas. Some of these microorganisms include the acidogenic microorganisms and the methogenic microorganisms. There are other gaseous products that are not needed, these include hydrogen sulphide; these are released into the environment because their concentrations are not harmful to the environment.

Finally, we were given refreshments and we took some photos.

This excursion has really clarified a lot of vague and confusing issues concerning the industrial production of beer. I must say that I amvery grateful for the opportunity to witness the production

process in its detail. I sincerely wish this exercise be highly encouraged in every department of the University, if possible, make it a compulsory exercise.

Thank You.