Automating Original Gravity measurement in beer making

One of the most important indicators to be measured in beer production is original gravity (OG). Original gravity measures the density of the wort (the liquid extracted from the mashing process of the malted grains) before fermentation. This density indicates the amount of fermentable sugars present in the wort, from which the potential alcohol content of the finished beer can be calculated.

The final gravity (FG), measured after fermentation, will be lower than the OG as the yeast consumes the sugars in the wort to produce alcohol. The difference between the original gravity and the final gravity can be used to calculate the alcohol by volume (ABV).

Original gravity is not only important for alcohol calculation, however. Monitoring the OG helps in maintaining consistency in the brewing process, to achieve a consistent flavour and mouthfeel, as well as alcohol content. It also provides essential information for brewers when designing and adjusting beer recipes and for predicting how the yeast will perform during fermentation. Higher OG worts generally have more sugars for the yeast to ferment, and knowing this helps in selecting the appropriate yeast strain and managing fermentation conditions to ensure a healthy and efficient fermentation process.

Traditional methods of determining OG and FG involve manual sampling of the wort and measuring its gravity using a hydrometer or a refractometer, resulting in a figure as specific gravity (density relative to water) or in °Plato. These measurement methods are calibrated to a particular reference temperature (usually 20°C), and if the wort is at a different temperature, the measurement must be adjusted. Such methods are time consuming and prone to error.

Making brewing more responsive and efficient with in-line measurement

Fortunately, an innovative solution FLOWave — an acoustic multiparameter flowmeter from Bürkert — is allowing brewers to measure OG and FG continuously in-line with unprecedented precision and reliability, eliminating labour-intensive sampling and calculation.

FLOWave is an application solution that can not only measure volume flow, but also determine the density factor and acoustic transmission factor to present the OG directly in °Plato. FLOWave also measures the temperature of the wort with an accuracy of ≤1°C, so that the OG value is automatically temperature-compensated. And because FLOWave leverages advanced Surface Acoustic Wave (SAW) technology, it dispenses with sensor elements in the measuring tube, which means no leaks, no material incompatibility, no maintenance, no pressure drops and easy cleaning.

FLOWave devices are part of a comprehensive system solution that requires professional calibration and installation by an approved Bürkert service provider. Utilising the Bürkert device platform EDIP, FLOWave integrates seamlessly into existing fieldbus systems. Additionally, the inclusion of a Wi-Fi module enables remote access to measurement parameters via a web browser, ensuring optimal performance even in difficult-to-access locations. This collaborative approach between the customer and Bürkert guarantees precise setup and reliable operation, fostering a successful partnership.

A flowmeter for all elements of brewing

Along with volume flow, temperature and density, FLOWave’s measurement technology also means that it can detect changes in fluid composition in real time, while the Acoustic Transmission Factor function detects bubbles, particles or solids in the liquid.

This means that in addition to measuring OG and FG °Plato (measured at the lauter tun and fermentation tank), it can also be used to monitor OG during the boiling process, as well as for other applications that would normally require multiple instruments, such as determining wort clarity, detecting media changes between production and CIP cycles, or monitoring heat exchanger water flows and temperatures to manage energy efficiency.

Special offer

At Bürkert, we understand the challenges that beverage manufacturers face in optimising their production processes. That’s why we’re excited to announce a limited-time offer for FLOWave, with prices starting from just $5,800. This exclusive promotion presents a unique opportunity for manufacturers to invest in cutting-edge technology that can revolutionise their operations and drive business growth. Whether you’re looking to improve efficiency, ensure product quality, or reduce operational costs, FLOWave offers a comprehensive solution that delivers tangible results.

Image credit: iStock.com/izusek