Bowing to beer pressure
The brewing industry is one of the oldest in the world. People from all walks of life and civilizations have been consuming alcohol for thousands of years. In fact, the discovery of late Stone Age beer jugs has established that intentionally fermented beverages existed at least as early as the Neolithic period (circa 10,000 BC).
Beer is the fifth most consumed beverage in the world behind tea, carbonated beverages, milk and coffee, and it continues to be a popular drink with an average consumption of 23 litres/person per year.
While the brewing industry has an ancient tradition, it is a dynamic sector using the latest developments in technology and scientific processes to drive new product innovation and quality assurance, and guarantee consumer safety.
All breweries need quality assurance testing to ensure the beer they produce is of the highest standard possible in terms of quality and safety.
Brewers are responsible for identifying steps in their activities that are critical to assuring product safety and ensuring that adequate safety procedures are identified, implemented, maintained and reviewed based on HACCP principles.
Adherence to HACCP is a vital part of brewers’ due diligence requirement to provide evidence that all reasonable precautions to comply with food safety legislation have been taken throughout the brewing process, from raw material intake through mashing, boiling and fermentation, to maturation and final packaging.
While beer is an inherently safe product, it can nevertheless be contaminated with foreign bodies, chemicals and microbiological spoilage organisms at any stage of the production process.
Putting beer to the test
Testing and analysis is a vital part of beer production to ensure brewers meet the exacting specifications laid down by the regulatory framework, and the quality standards required by consumers and retailers. This applies to materials at all stages of the process – including ingredients such as malted barley, hops and yeast, and processing aids such as filter media or finings.
The tests available range from relatively straightforward analyses, such as colour or alcohol content, to tests for biological, chemical or physical contaminants. For example, Campden BRI’s brewing division offers a wide range of tests, with over 30 of its methods UKAS accredited, and can offer rapid turn-around. This ensures breweries can take countermeasure steps as quickly as possible if a taint or contamination issue is suspected and address the contamination issue head-on, preventing any costly losses of large batches of beer or even product recall.
Potential brewing contaminants
Microbial contamination can originate from a variety of sources in the brewing process. Raw materials, air, brewing water, additives and even pitching yeast can act as potential sources of contamination.
Residues may remain in brew house tanks, pipelines, valves, heat exchangers and packaging equipment harbouring microorganisms that, again, represent a potential source of recontamination. The effects of micro contamination range from comparatively minor changes in beer flavour and fermentation performance to foul, abnormal flavour and aroma defects, turbidity problems and incomplete fermentation.
In terms of safety, the biggest threat from microorganisms is the formation of mycotoxins – a group of chemically diverse naturally occurring substances produced by a range of filamentous fungi or moulds.
The mycotoxins of greatest concern are produced by mould species from three main genera – Aspergillus, Penicillium and Fusarium. They include aflatoxins, ochratoxin A, zearalenone, trichothecenes, and fumonisins.
Mycotoxins can affect a range of ingredients and raw materials. Knowing which mycotoxins could present a hazard in which materials, and their stability during processing, is an essential part of planning risk management strategies, HACCP plans and analytical monitoring programmes.
Given their significance to the industry, Campden BRI has developed and offers a full range of mycotoxin testing covering deoxynivalenol (DON), Ochratoxin A, Aflatoxin, Cytochalasin E and Fumonisins using various methods, including liquid chromatography linked to mass spectrometry (LC-MS/MS), which allows simultaneous screening for a range of mycotoxins.
Nitrosamines (eg NDMA)
In the late 1970s it was discovered that nitrogen oxides in malt kiln flue gases could react with compounds within the malt to produce nitrosamines.
As most nitrosamines are potential carcinogens, the malting and brewing industries quickly introduced procedures that restricted or prevented their formation, leaving levels extremely low and thereby assuring the safety of product for consumers.
Again, as a result of its importance to the sector, Campden BRI regularly tests for NDMA formation, and ATNC (apparent total N-Nitroso compounds), as part of its range of tests available to the brewing industry to safeguard quality and assure product safety.
Chemicals may be present in beer samples completely by accident (eg cleaning chemicals, pesticides, packaging migration) or they may be present as a result of malicious intent.
Potential contamination issues can be picked up via routine testing and sampling at any stage of the brewing process. Occasionally a taint – which is a quality defect not a safety concern – may be discovered in the end product itself by consumers.
In the case of a taint being identified, even if the beverage is safe both chemically and microbiologically, the product will be rejected by consumers if it ‘doesn’t smell right’ or ‘tastes a bit off’. This can lead to a loss in production, sales and consumer confidence in the brand.
Campden BRI’s approach to identifying and providing advice on the source of taints and off-flavours is to combine its expertise in sensory and analytical chemistry. Firstly, an expert sensory team profiles the taint in order to provide an indication of the likely source of the taint or off-flavour. Secondly, this work is backed up by analysts who may use the aforementioned sophisticated analytical techniques such as LC-MS/MS or GC-MS to identify the compound causing the taint.
Chemical analytes of significance include:
- Mycotoxins and nitrosamines – as mentioned above
- Pesticide residue analysis
- Taints and flavour defects
- Processing contaminants (eg acrylamide, 3-MCPD, and 4-MeI)
- Packaging migrants (eg Bisphenol A)
Even if there are no evident contamination issues, it is good practice to have a sampling plan in place and, at intervals, to check process samples for possible contamination. This will help to understand where any taints or contamination originate.
In addition, the building of historical data for trending is also valuable as it will help to proactively respond to developing issues before they can result in damage to the final product.
Advances in testing
Today there is a range of tests – including conventional approaches, as well as rapid methods of testing and cutting edge analytical equipment –available to brewers to assure product quality and safeguard consumers, and to provide analytical data as quickly and effectively as possible.
The new, state-of-the-art liquid chromatography/ mass spectrometry (LC-MS/MS) system Campden BRI recently invested in provides clients with a more effective and accurate organic contaminant analysis service than ever before. The improved suite of LC-MS/MS instruments provides the capability to expand the analyses available for mycotoxins, agricultural contaminants and low levels of pesticides, as well as chemical contaminants such as acrylamide and BPA, effectively creating a ‘one-stop-shop’ for all the brewing industry’s testing and analysis needs.
Brewing Analytes Proficiency Scheme
Major operational and commercial decisions are made on the basis of analytical results and it is therefore vital that these results are accurate, reliable and interpreted correctly. Proficiency testing (PT) offers a highly effective way for laboratories to check how they are performing.
The Brewing Analytes Proficiency Scheme (BAPS) is an international UKAS accredited scheme, jointly administered by Campden BRI (Nutfield) and LGC Standards, designed to promote quality in the measurement of a range of chemical, microbial and sensory analytes in beer, and to help participants monitor and improve the quality of their measurements.
BAPS includes chemical, microbiological and sensory analysis. Participants analyse ‘blind’ test samples using standard industry methods and the results are sent to the scheme organisers. Each participant then receives a report comparing their performance with that of all other participants.
Participation in the BAPS scheme enables brewers, from the smallest microbreweries to the largest brewing companies in the world to:
- · Demonstrate the effectiveness of their own quality systems
- · Compare their laboratory’s measurements with those of their peers
- · Demonstrate competence to third parties such as accreditation bodies, regulators and customers
- · Monitor trends in measurements over time
- · Monitor an individual’s capability as part of their training programme