As the craft beer sector continues to grow, mainstream beer sales continue to decline. Beer production in Europe has been in decline since the 1970s, and with more and more drinkers demanding a higher standard of drinks, the pressure for brewers to create a quality product which also has a long shelf life is greater than ever. Kegged beer is typically required to last several months, and bottles and cans even longer, with expected shelf lives as long as a year. If beer is to survive unspoiled for this long, the organisms responsible for the spoilage must be completely eliminated or properly controlled.
One challenge is the stabilization of beer in order to reduce microbial growth within the packaged product and therefore increase shelf-life. Currently, the most common method of microbial stabilization is flash pasteurisation. Flash pasteurisation quickly destroys the main microorganisms responsible for beer spoilage by cooking the beer to temperatures of over 70oC for 15-30 seconds. More recently, brewers have been turning to a gentler method of stabilization known as sterile filtration. Sterile filtration, such as that offered by Parker Bioscience, uses membrane filters which provide a higher level of microbial security to the brewer, without the need for the cost-inefficient high temperatures. Parker Bioscience, along with our partner Agidens, have calculated sterile filtration can reduce operational costs by up to 44% compared to flash pasteurisation. This calculation considers all aspects of running costs including energy consumption, water loss, beer batch loss during PU variations and consumable spend.
Interested in learning more about the benefits of sterile filtration for beer flavour and its impact on product losses? Download this white paper: Reducing the cost of microbial stabilisation of beer.
Furthermore, an experiment was recently conducted with a leading UK brewery. The experiment aimed to determine whether or not sterile filtration increases the shelf-life of beer and if it helps maintain the desired characteristics of the beer better than flash pasteurisation.
The brewery provided one batch of beer, of which one half was treated using pasteurisation and the other sterile filtration. Both sets of beer were then compared by means of a triangular taste test.
The results confirmed that the two technologies do differ in their impact to beer flavour and characteristics. The sterile filtered beer was identified as more bitter, and crisper. Whereas flash pasteurised beer was identified as being sweeter, softer and with a taste of sulphur – characteristics not desired by the brewery.
The brewery also assessed the impact on shelf-life of the two processes.
After 12 months for force shelf-life analysis, most of the bottles which had been flash pasteurised, over 90% of them, had a very strong, or moderate oxidised taste.
When compared to the flash pasteurised beer, over 95% of the sterile filtered bottles had a total absence or very low level of staling, or oxidised flavour.
This result clearly demonstrates that sterile filtration protects the shelf-life of beer more effectively than pasteurisation. This result supports scientific literature which hypothesises that thermal treatment is detrimental to beer’s character and can actually catalyse staling.
To summarize, the costs of brewing will keep rising and the brewing industry will continue its shift towards craft beer — putting more pressure than ever on breweries to lower operational costs, increase beer shelf life and create better-tasting beer. Sterile filtration could be the answer.
Interested in learning more about the benefits of sterile filtration for beer flavour and its impact on product losses? Download our complete white paper, Reducing the cost of microbial stabilisation of beer.
This post was contributed by Ian Curran, market development manager, Parker Bioscience Division, United Kingdom.
Parker Bioscience Division offers filtration solutions to protect the quality and taste of beverage products. By working with our application experts, manufacturers can develop a tailored solution to ensure their beverage is free from contamination, full of flavour and visibly clear.