Beer is by far one of the oldest and most widely consumed alcoholic drinks in the world dating back to the Bronze Age.

With the growing “premiumization” of beers, a shift and advancement in the analytical procedures has been an inevitable move. In the distant past, this was done through taste, smell, flavor, and visual analysis rather than instrumentation. In modern times, however, analytical instrumentation plays an increasingly important role in the brewing process given that numerous factors that are just not that easy to taste, smell, see or feel, contribute to the success or failure. As Henry Ford once said, “You can’t improve what you can’t measure”.

Liquid chromatography-Mass spectrometry for mycotoxin screening

Any brewery, whether a craft, regional or multi-national, all share the same dream: to have their product hits the shelf in prime condition and is safe for consumption. Mycotoxins are however an existential threat to this. Dry goods such as malt, hops and barley used in the manufacture of beers are often susceptible to mycotoxin producing fungi. Mycotoxins, as we know them, are a food safety risk and should never be allowed to enter the food chain. A recent analysis of marketed beers however found that almost half contained mycotoxins. A combination of liquid chromatography and mass spectroscopy (LC-MS), is able screen for multiple mycotoxins in a single analysis, helping in early detection. The technique is also used to monitor the content of alpha- and beta-acids that contribute to beer bitterness and flavor stability.

Proton Transfer Reaction-Mass Spectrometry

The interaction of VOCs in a particular way produce the distinctive flavors and aromas of different beers. The proton transfer reaction mass spectrometry (PTR-MS) used in conjunction with gas chromatography allows detection of even low concentration volatile organic compounds (VOCs). PTR-MS is a technique developed almost exclusively for the detection of gaseous organic compounds in air. However, the high-concentration of ethanol in beer titrates the PTR-MS instrument, preventing the accurate measurement of lower concentration VOCs that are present in the liquid or headspace. Additionally, PTR-MS cannot distinguish between isomers, such as different monoterpenes or sesquiterpenes (aroma compounds), which have the same elemental composition but different molecular structures.

To quantify low concentration VOC isomers, a fast gas chromatogram (GC) – which can separate isomers – is coupled in line with a TOFWERK Vocus 2R PTR-TOF. The Vocus PTR-TOF is a proton transfer reaction mass spectrometer for sensitive, real-time detection of VOCs in industrial, laboratory, and field applications. As ethanol elutes from the GC well before most aroma compounds, quantitative flavor analysis of alcoholic beverages becomes possible.

NIR moisture meters cutting the wait time to nearly nothing

At the beginning of the beer brewing process, testing the moisture content in barley and hops and the microbiological content in water can help safeguard the quality and consistency of  beer. Control of malt moisture will help in optimizing extract and breakage and will prevent decline in quality during storage. In the world of obtaining accurate readings of moisture levels, methods like the Karl Fischer method, have weathered the test of time, with decades of use. However, newer and flashier methods like the near infrared (NIR) technology are finding their place in the industry. NIR moisture meters measure the absorbance and reflectance of light to determine the moisture levels; the more light that is absorbed, the higher the moisture content.

Unlike the Karl Fischer method, NIR moisture meters are non-destructive and non-contact, so you never lose your initial sample. An example of such is the OMNIR on-line near infrared moisture sensor developed by Finna Sensors, a developer of advanced industrial sensors and hand-held meters. OMNIR is an intelligent all-sensing solution that was created to thrive in a networked world with built-in Internet of Things (IOT) and Artificial Intelligence (AI) features. It leverages the latest electronics and software to offer a ground-breaking solution for manufacturers. Companies like Sartorius and Kent have also come up with NIR moisture meters. The Sartorius MA160 Infrared Moisture Analyzer offers reliable, precise and versatile moisture analysis in both  research and manufacturing environments.

Modern turbidity meters also use an infrared LED light source to swiftly check that their fining or filtration process is yielding a desired end product. Turbidity refers to suspended, insoluble material which can appear in the final product. It can occur due to unwanted microbes, wild yeast or protein particles. These deposits, although not unsafe to consume, can significantly alter the flavor profile of the beer, adding unpleasant acidity, sourness, or even off-flavors.

Water quality testing

To achieve the great taste of beer and ascertain the cleanliness of equipment after cleaning process, water quality check must be carried out in the various stages of brewing process with reliable and accurate instruments. The water quality parameters to be tested are determined by a beer manufacturer’s water source. Water acquired from municipal water systems often can contain chlorine or chloramines, which can give beer a plastic “Band-Aid” taste. As for well water, the hardness and mineral content vary from coast to coast. Based on these facts, anyone involved in the brewing of beer should consider which minerals are potentially being introduced to the brews. The most common water quality parameters checked are chlorine, pH, total alkalinity, residual alkalinity, total hardness, calcium hardness, magnesium hardness, chloride, sodium and sulfate.

Having the advantages of less maintenance design, low-volume sample requirement, and hassle-free operation, the HORIBA LAQUAtwin pocket meters and LAQUA dissolved oxygen (DO) handheld meters and electrodes are recommended for home and commercial beer brewers. The LAQUAtwin series are presently available for measuring pH, EC/ TDS,Sodium, Potassium, Nitrate and Calcium ion concentrations as well as Salinity.

Regular total colony counts and tests to identify coliform bacteria, specifically E.coli, are recommended for microbiological quality control of water. Sartorius’ e.motion Dispenser Membrane filters optimize water testing workflows and save time. They dispense filters automatically eliminating the need for manual operation. The filters also simplify the colony counting due to clear colony morphology and distinct grid lines. The company also has a Microsart e.motion Dispenser which automatically dispenses membrane filters for water testing in the brewery by touch of a button, hands-free motion detection or a foot switch to minimize risk of secondary contamination.

The beer freshness package is the only established way of determining how parameters in operation, materials and process design can positively or negatively impact beer quality and freshness during the beer production process.


Spectrophotometric technology

Spectrophotometric technology has been used by leading brewing companies around the world to maintain product quality and reputation. It continues to show potential for other applications in beer brewing and product development. Its ability to provide rapid and precise measurements has steered its wide adoption. UV-VIS spectrophotometric technology helps monitor quality control in beer production and development. Key regulatory groups such as the American Society of Brewing Chemists (ASBC), European Brewery Convention (EBC), and the Association of Official Analytical Chemists (AOAC), all recognize UV-VIS spectroscopy as a reliable analytical method for testing beer. From color to taste, this technology assures companies that their products will meet consumer demands. Along with other analyses, color measurements produce valuable information that allows comparisons to be made between the sample and predetermined parameters.

There are currently two standard measurements for beer and wort color: Standard Reference Method (SRM1) and the European Convention (EBC). Both of these methods use spectrophotometric technology and light absorption measurements to quantify color and provide information on various aspects of brewing and beer formulation. Mettler Toledo’s UV/VIS Excellence spectrophotometers are used by brewing companies throughout the world to achieve a consistent level of quality, during their product development and beer production processes. They provide a variety of measurements during and after beer production to determine color, taste, bitterness, total carbohydrates and more. HunterLab is also a leader in spectrophotometric technology and specializes in color measurement and quality control.

Plasma-atomic emission spectroscopy (MP-AES) is also a type of spectrophotometry established for the detection of calcium, copper, iron, potassium, magnesium, and sodium in finished or packaged beer. The instrument measures the elemental concentrations based on the emission of light for each element as the sample is passed through a plasma

Determination of Gluten Using the R5 Competitive ELISA Method

Food allergies are a major public health concern affecting between 220 and 250 million people worldwide. It is therefore imperative that those who are sensitive to gluten can be confident consuming foods that are labeled gluten-free or that are naturally gluten-free. The only process capable of ensuring that a product is 100% gluten-free is to utilize 100% gluten-free grains. Products denoted as gluten-free must contain no more than 20ppm gluten, as measured by ELISA.

ELISA is the major commercially available laboratory procedure currently used to determine the presence of gluten within food products. But a drawback of this method is that it cannot adequately quantify gluten that has been hydrolyzed, such as in beer. As such, mass spectroscopy (MS) is emerging as the most promising alternative to ELISA in allergen analysis. As opposed to ELISA which is dependent on the 3D structure of food, MS when coupled with liquid chromatography (LC), caters for the structural changes experienced during processing: basing the results on the amino acid sequence of an allergen. The samples are easy to prepare and better yet MS can simultaneously detect more than one allergen, with a shorter results generation time.

Electron paramagnetic resonance (EPR) for beer freshness

Also known as the Electron Spin Resonance (ESR), EPR is used to directly measure free radical production in the beer during a forced oxidation assay. The assay is based on an EPR-spin trapping experiment in which free radicals form covalently bound adducts with the Phenyl N-tert-butylnitrone (PBN) spin trapping reagent. The accumulation of these adducts is detected by EPR during the forced oxidation period and directly reflects the resistance or lack thereof of the beer to oxidation.

The Beer Freshness Package is the only established way of determining how parameters in operations, materials and process design can positively or negatively impact beer quality and freshness during the beer production process. The package is as a result of an alliance between FlavorActiv, a world leader in sensory solutions and Bruker, an American manufacturer of scientific instruments. It has been upgraded to include Bruker’s microESR benchtop instrument, which is fully supported by applications training, customized reagents, GMP Flavor Standards and technical support. The microESR is a small, portable research-grade instrument that weighs only 10 kg and can fit easily on a bench, fume hood, or even be transported into the field. According to Bruker, it requires no special installation or regular maintenance, meaning even the most inexperienced researcher or student can benefit from the analytical power of EPR. It allows users to detect the concentration and composition of free radicals with a simple software interface and easy-to-follow workflows.

As beer continues to become a common pleasure for many people, analytical techniques will continue becoming increasingly important in the brewing industry, for both safety screening and monitoring the brewing process.

This feature appeared in the May/June 2022 issue of Food Safety Africa. You can read the magazine HERE