Cold Link Africa March / April 2020 | Page 16

PROJECT INCORPORATING COLD CHAIN Continued from page 1 Hey Joe Brewing crafts the perfect beer with glycol cooling W ith supposed roots going back cold glycol. Warm glycol is pumped to Belgium, the brewery dates from the top of the glycol tank to the back to the 60s, owned by a chiller, cooled and pumped back into fictional character named Joe who had the bottom section of the tank. Cold a deep desire to land in Africa and glycol at 0°C is pumped to the brewery brew the perfect Belgian beer using to where it is required. Warm glycol is African inspired ingredients. pumped back into the top section of To create the perfect brew, they use glycol cooling in different areas Hey Joe Brewing installed a glycol cooling system. the glycol tank. for different purposes. An Aermec air- GLYCOL COOLING cooled chiller is used to cool glycol to The brewery uses glycol cooling in the -4°C. The chiller has a cooling capacity following methods: of 66.1kW and a water flow rate of • 12 629 ℓ/h. It uses a R410A refrigerant. Wort is the liquid extracted from the A stainless-steel tank is also used to mashing process during the brewing Wort cooling of beer or whisky. Cold water at 4°C the middle containing a hole in the is used in a two-phase SPX plate heat centre to partially separate the hot and exchanger to cool wort from 96-100°C store glycol. The tank has a plate in to either 19°C – similar to ale style beers is done to isomerise alpha acids from – or to 12°C. The wort is then extracted hops, concentrate wort (water boil- from malted barley and wheat that off), sterilise wort, and boil off undesired are obtained during a process called flavours like dimethylsulphide (DMS). The wort is cooled within about 80 ‘lautering’. During this process the liquid wort is separated from the spent grain. Fermentation tank in cellar. minutes depending on the batch size The wort is boiled for 60-90 minutes at a flowrate of 30-35hℓ/h. This step at approximately 100°C. Wort boiling is vital so that yeast can be added to wort as quickly as possible at its desired temperature at either 10-14°C for lager style beers or 18-24°C for ale style beers. • Cold water cooling The cold water used to cool wort is cooled by a small two-phase SPX plate heat exchanger. Dependent on the season, water in an 8 000ℓ stainless steel tank is cooled from 18-25°C to 4-6°C. A circulation pump is used to pump water from the tank through the heat exchanger and back into the tank. This pump is also used to pump the cold water to the wort heat exchanger. This water obtains the heat from the wort and gets pumped to a hot water tank at about 70°C. So, the heat energy is not wasted but rather recuperated for hot water usage at a later stage. • Flash pasteuriser cooling After fermentation and maturation in the CCT (4-6 weeks), beer are either filtered or centrifuge to removed yeast and other solids where after flash pasteurisation takes place. This involves heating beer to 72°C for 30 seconds to inhibit the growth of potential beer Bright beer tanks. 16 www.coldlinkafrica.co.za spoilage microorganisms. This process COLD LINK AFRICA • March/April 2020