One of the key considerations when choosing a stabilisation method for a brewery’s operations is how the flavour profile of the final product could be affected. There is little point in a finished beer product having an extended shelf life if the aroma and flavour of the end product is greatly compromised by the stabilisation method.
And with the continued growth off the craft beer market – driven by drinkers who put a greater emphasis on quality rather than quantity – brewers need to have the confidence that their potentially award-winning new beer, which they have invested so much time and know-how into, still has the wow factor when it hits the pubs, ale festivals and supermarket shelves.
While most stabilisation techniques will impact the characteristics in some way, the correct choice of process and materials can help to protect the unique characteristics of a beer. Pasteurisation has long been a go-to method for stabilising the shelf life of beer, however, newer techniques such as sterile filtration can significantly improve the overall quality of the finished beer.
Beer quality considerations
While flash pasteurisation used to mean heating the beer to 60°C for 10 minutes depending on the beer specification, tunnel pasteurisation now enables the process to be done in seconds, albeit at more severe 70°C. This represented an evolution in an attempt to protect the beer from over-pasteurisation and to preserve the complex molecular compounds which make up the unique characteristics of the beer.
Even with the evolution of pasteurisation, the risk of damaging the beer’s unique characteristics is still present – no matter how precise the process control – and the impact of pasteurisation on beer quality is widely accepted. The final stabilisation of beer by microfiltration has commonly been acknowledged as a gentler method of stabilisation, generating a cleaner, fresher, more natural flavour when compared to pasteurisation.
In a recent study performed by a large UK brewery, the effects on taste of flash pasteurisation were compared to cold stabilisation with Parker's BEVPOR BR filters. In this study, the same batch of beer was split, where some was sent for bottling via flash pasteurisation and some was sent for bottling via cold stabilisation. The bottled beer was then compared in triangular taste tests where the sterile filtered beer was identified to have the most appealing taste and longer shelf-life.
As well as damaging the flavour profile, flash pasteurisation can also contribute to significant losses in final beer volume. During the pasteurisation process, if any changes in heat, pressure, or flow rate occur, the beer is typically dumped to drain until the problem is rectified.
Should these problems occur, the result can be a huge amount of product loss. Sterile filtration is not dependent on such restrictions, so does not suffer from the same wastage.
Interested in learning more about the benefits of cold stabilisation for beer flavour and its impact on product losses? Download our complete whitepaper, Reducing the cost of microbial stabilisation of beer.
This post was contributed by Daniel Vecsey, 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.