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hundreds of years except that it has bene ted hugely with developments in both process and enzyme technology. Further, the wider application of enzymes allows brewers to brew with a variety of raw materials that provide alternative starch sources. Take Eagle Lager, a beer brewed in Uganda from locally sourced sorghum. Eagle Lager was developed as a new brand of Africa’s traditional opaque beer known as Chibuku; Eagle is a clear beer created by AB InBev’s Nile Breweries Ltd in collaboration with DuPont. Brewed using locally grown sorghum, Eagle Lager creates a sustainable income for more than 20,000 smallholder farmers, while also providing Nile Breweries Ltd with a secure local supply of sorghum. Local sourcing in Africa and in other markets is a win-win for both companies and communities alike. HERE COMES THE SCIENCE So, what exactly is an enzyme? An enzyme is essentially a complex protein that induces chemical changes in other substances. Enzymes are natural products, present in all living things, including our own body. ey act as catalysts to speed up biochemical reactions; they are critical to our ability to digest food and produce energy that allows us to function every day. e action of an enzyme can increase the reaction speed by at least a million-fold. e process of malting activates the enzymes in the barley kernel. During the mash the malt enzymes break down the starch to create fermentable sugars (glucose, maltose); the yeast converts these sugars into alcohol. Malt enzymes (which include alpha- and beta-amylases, beta-glucanases, xylanases, proteases) do have some limitations: they work at particular temperatures and within certain pH values. ese parameters have an important impact in beer production. Each of the enzyme groups is favoured by di erent temperature and pH conditions. A brewer can adjust the mash temperature to suit each successive enzyme's function and thereby customise the wort to taste and purpose. Mash pH should be in the 5.2-5.5 range with a preference towards the lower end – pH is simply a measure of how acidic or alkaline a solution is. Optimising both the temperature and the pH will give better conversion of starches to sugars and will lead to downstream improvements to give improved beer clarity and avour. Despite optimising these process parameters, often the resulting enzyme activity in the mash is too little. When this happens, it can lead to low extract yield (due to reduced amounts of fermentable sugars), poor wort separation, slow fermentation giving reduced alcohol production, poor beer ltration, a variable process consistency – all in all resulting in a beer of inferior quality. LOCAL INGREDIENTS, LOCAL TASTES In the case of brewing with alternative raw materials (commonly known as adjunct brewing) their constituents must be thermally broken down in the mashing process with the addition of barley malt and/or exogenous enzymes. ese exogenously applied enzymes can accelerate the production process, improve its e ciency, and save on costs by reducing energy and water usage. Commercial enzymes are developed to be targeted towards the raw materials in the brewing recipe and the process requirements. It’s both an art and a science. By introducing exogenous enzymes, brewers have greater exibility in the choice of raw materials for brewing since there is less dependency on malt enzymes. Beers made with sorghum, cassava, rice, corn/maize, millet, wheat, barley (i.e. adjuncts) with and without malt or combinations of these are available globally today - all great tasting beers and of notable brands. Acting as catalysts, enzyme solutions not only result in better, consistent, delicious beer, they also optimise processes to make production systems work more e ciently, sustainably and cost-e ectively. Driven by increasing urbanisation, a growing middle class and positive economic growth, Africa is becoming the world’s fastest-growing beer market, and enzyme technologies can and will further help unlock the potential of this new consumer block. To tap into markets in areas of the world with great growth potential, brewing companies are already harnessing the power of local sourcing, with the help of enzymes, to create new brands that appeal to distinctly local tastes. Major brewing companies are also integrating local sourcing initiatives into their operations around the world as a way of adding commercial and social value to already-stated sustainability goals. Growing through innovative local sourcing initiatives is possible, but not without ensuring that production processes are working e ciently… easily achieved with a little help from enzymes. Photos by: Chailalla & Benoit Daoust - Shutterstock.com Africa is becoming the world’s fastest-growing beer market 48 | Spring 2018 | ontapmag.co.za