Beer - Quality Control by Anion Monitoring

The majority of anions found in beer are a consequence of the water (contains chloride, phosphate, sulfate, nitrate, fluoride) used during the brewing process.

Monitoring the anion profile is an important quality control step in the brewing industry because anions can affect the flavor of the finished product. If the level of chloride is above 250 mg/L, then the sweetness of the beer is enhanced but it can hinder yeast flocculation, so it needs to be carefully observed. An excess of sulfate has been found to give a sharp, dry edge to well hopped beers and so the level present should be minimized as much as possible bearing in mind that sulfate occurs naturally in water. Phosphate is present in the malt and buffers the mash to a slightly acidic pH. Quantifying the level of nitrate is important as excessive amounts can hamper the fermentation process after conversion to nitrite.

Analysis of beer by ion chromatography
Metrohm's well known MIC-2 Advanced modular anion system with chemical suppression is used for the analysis of beer. In the method described herein, light beer wort is being analyzed for the determination of fluoride, chloride, phosphate and sulfate contents.

Simple sample preparation steps and the need of only small amounts of samples are the major advantages of ion chromatography as an analytical technique: dilution is the only sample preparing step required. Dilution and moreover the whole beer analysis can easily be automated using the 838 Advanced IC Dilution Sample Processor.

Advanced IC Dilution Sample Processor for inline sample dilution The 838 represents the latest generation of high-performance sample processors for IC. It sets new standards regarding flexibility, sample preparation, liquid handling and sample throughput; sample volumes range from 500 µL to 250 mL, 999 sample positions can be accessed. With up to three Dosinos, two membrane pumps and a bidirectional peristaltic pump the liquid handling possibilities are unlimited. Version with integral two-channel peristaltic pump and integral six-way injection valve. Sample rack, 800 Dosino and 801 Magnetic Stirrer to be ordered separately.