Mission Improbable: Rapid Total Sugar Reporting for Beer by Mass Detection


How mass detection allows us to tell the beautiful truth about beer

By Larissa Burns, Group Technical Analyst, Lion Co.  How mass detection tells the truth about beer

I’ve been working at Lion as their analytical specialist for eight years, predominantly using and developing methods for the enviable task of analyzing beer. I have around 20 years of chromatography experience in several different fields, including food and pharma – and I’m pleased to say I still love analytical chemistry and chromatography; there’s always a sense of discovery as you tackle new challenges. You never quite know where the problem solving process might take you – but it’s exciting when you get there.

Lion has around 6700 employees in Australia and New Zealand, making it one of the largest food and beverage companies. There are essentially two parts to the business: “Dairy & Drinks” and “Beer, Spirits & Wine” – but beer production is a huge part of what we do. Many readers will be familiar with our XXXX beer and Tooheys brands, but we’ve also got a fast-growing craft beer portfolio (led by our James Squire brand) and we also produce international beers, including Heineken, Guinness and Kirin under strict license agreements.

Sweet focus

Each of our breweries has a laboratory for quality control analysis. I work in a centralized lab that focuses on supporting our brewery operations at a higher level, with a focus on spotting trends or gathering information across our portfolio. For example, we might perform projects that focus on calcium levels, certain hop compounds, or volatile aroma compounds. We’re also there to support the quality control (QC) labs if they detect a problem by troubleshooting to determine what might be going wrong in the brewing process.

Lately, we’ve been working on several projects that demand the quantitation of low levels of sugar. Sugar analysis isn’t something new to us – we monitor sugar levels at various early stages of the brewing process. However, Lion was also interested in monitoring fermentation profiles to completion – and we wanted to introduce voluntary nutritional panels across our beer portfolio. The latter feeds into a larger education program called “Beer the Beautiful Truth,” which aims to bust common myths about beer and communicate some analytically supported evidence, including the fact that Lion’s beers contain, on average, less than 0.1 percent total sugar.

We were using electrochemical detection to measure the relatively high levels of sugar in wort (the liquid extracted from the mashing process), but when it came to beer quantitation, it was much more challenging because of the inherently low sugar levels. Our run times were long, we were struggling with sensitivity, and there were some interferences. It’s fair to say we were working at the limit, so it seemed the opportune time to seek out alternatives.

The Waters ACQUITY UPLC H-Class with ACQUITY QDa mass detector was a combination that had a lot going for it – not least the fact that Waters demonstrated a cost-effective and robust proof of concept for our application. Another important factor in our decision to go with the ACQUITY QDa was the fact that it was easy to use – you switch it on, wait for it to complete its start-up cycle, and you’re ready to run samples. We were already familiar with Empower software, so that made the decision even easier.

Working with a mass detector is much like working with any other detector – you set up your sample set, add your vials, and hit “go.” When you come back after the run, even the data processing is similar to what you’d expect with something like a PDA detector.

Our method makes things slightly more complicated, because we’re monitoring six sugars at four different ion masses, so we need four channels. But we found pretty quickly that it’s really not that different to running an LC system with one channel.

Confidence in the beautiful truth

Even though beer is 90% water and typically around 5% alcohol, it’s actually a pretty complex mixture; there are proteins, carbohydrates, sugars, hop compounds, esters, and so on – but all at low concentrations. Notably, the contract analytical food labs that we approached about sugar analysis in beer could not offer the reporting limit we were looking for – they typically deal with higher concentrations (as found in other foods). So we had to develop our own method.

The ACQUITY QDa mass detector is sensitive enough to work at the concentration levels of sugars we are interested in (LOD is around 1–2 μg/mL) but crucially, by combining retention time and mass information, we are also now able to achieve greater selectivity.

In the nutritional project mentioned above, we needed to analyze around 1500 samples in just a couple of weeks – and it was quite a task. Put simply, we couldn’t have done it without the new system. With the old system, each injection would have taken 30 minutes, and we needed to get through 100 samples per day – sadly, there aren’t 50 hours in a day…

Upgrading to the ACQUITY UPLC and QDa as a package was fantastic – we got a double boost to our method. Each injection is around 5 minutes, so we could run 100 samples overnight, doing the sample preparation and data processing during the day.

Ultimately, that means getting through our work much faster. And because we were able to combine mass information with retention times, we were a lot more confident in the results that we generated.

It’s great to have the power of mass data in our lab without the usual headaches – or the need for a mass spectrometrist!

Larissa Burns is a Group Technical Analyst at Lion Co., Sydney, Australia.

Originally produced and published by The Analytical Scientist for Waters: Mass Data Made Simple.

 

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