Carbonated beverages, also known as fizzy drinks, are made through a process called carbonation. The carbonation process involves dissolving carbon dioxide (CO₂) gas in a liquid, typically water, to create the characteristic bubbles and effervescence.
How are Carbonated Beverages Made
Here are the basic steps involved in making carbonated beverages:
- Water Treatment: The water used as the base for the beverage is treated to remove impurities and ensure its quality.
- Syrup Preparation: Depending on the type of carbonated beverage being made, a syrup is prepared by mixing ingredients such as flavorings, sweeteners, and preservatives with water. This syrup provides the desired taste and characteristics of the beverage.
- Carbonation: Carbon dioxide gas is added to the water or syrup mixture under pressure. This is typically done in a carbonation tank or carbonator, where the gas dissolves into the liquid. The amount of carbonation can be adjusted to achieve the desired level of fizziness.
- Mixing: The carbonated water or syrup is mixed with other ingredients, such as fruit juices or concentrates, to create the final beverage. This step ensures that the flavors are evenly distributed throughout the drink.
- Bottling or Canning: The carbonated beverage is then filled into bottles or cans, which are sealed to maintain the carbonation and prevent any contamination. This is usually done in a controlled environment to ensure hygiene and product quality.
- Quality Control: The finished products are subjected to quality control tests to ensure that they meet the desired taste, carbonation level, and safety standards. This includes testing for consistency, carbonation retention, and microbial contamination.
It’s important to note that the specific process and ingredients used may vary depending on the type of carbonated beverage being produced, such as soda, sparkling water, or soft drinks.
Ensuring Carbonation Quality with FTIR Spectroscopy
Safeguarding the purity of CO₂ is crucial for the quality and safety of the final product. In light of this, beverage companies utilize carbon dioxide purity monitoring systems to provide a comprehensive solution for measuring trace impurities in CO₂ gas down to single-digit parts-per-billion (ppb) levels, as well as absolute purity.
An FTIR gas analyzer, which is capable of performing all relevant analytical measurements except oxygen, is often used to accomplish this task.
Fourier transform infrared (FTIR) spectroscopy, is the preferred method of infrared (IR) spectroscopy. When IR radiation is passed through a sample, some radiation is absorbed by the sample and some passes through (is transmitted). The resulting signal at the detector is a spectrum representing a molecular ‘fingerprint’ of the sample. The usefulness of infrared spectroscopy arises because different chemical structures (molecules) produce different spectral fingerprints.
FTIR spectroscopy offers a vast array of analytical opportunities in academic, analytical, QA/QC and forensic labs. Deeply ingrained in everything from simple compound identification to process and regulatory monitoring, FTIR covers a wide range of chemical applications. (Learn more about the basics and the value of this popular technique by visiting our online FTIR academy.)
Analyzing Carbon Dioxide Purity in Beverages with FTIR
We tested the performance of a CO₂ FTIR monitoring system to see if it meets the requirements of the International Society of Beverage Technologists (ISBT) and European Industrial Gases Association (EIGA) Standard for the measurement of key impurities in CO₂.
The analyzer incorporates a deuterated triglycine sulfate (DTGS) thermal detector, which has a spectral range of 600–5,000 cm-1. This broad range allows for the measurement of all infrared active impurities, as well as the direct measurement of absolute CO₂ purity, which eliminates the need for cumbersome wet methods (such as Zahm-Nagel purity testing). By using incredibly precise pressure and temperature controls, the system is capable of measuring CO₂ at 100 ± 0.02% simultaneously with trace impurities.
Within the system, an oxidizer module converts all reduced sulfur species to sulfur dioxide (SO₂), which is then measured by the analyzer to determine the total reduced sulfur impurity level in the CO₂. This is a more reliable method compared to industry-standard UV fluorescence analyzers, which are prone to maintenance issues and extended downtime.
A series of tests were conducted to demonstrate the accuracy, repeatability, and response time of the CO₂. absolute purity measurement. The system was found to have excellent accuracy and repeatability, with each CO₂. replicate being 100 ± 0.02%, and the relative standard deviation (RSD) being less than 0.015%.
Additionally, the system was tested for the limit of detection (LOD) for impurities. This assessment demonstrated the minimum amount of impurity that can be detected above the background in a representative gas matrix.
The accuracy, linearity, and precision of impurity measurements near the maximum allowable concentration were also evaluated. The system demonstrated excellent precision and accuracy near the upper alarm threshold.
The FTIR-based beverage-grade carbon dioxide (CO₂) purity monitoring system met the requirements of the International Society of Beverage Technologists (ISBT) and European Industrial Gases Association (EIGA) Standard for the measurement of key impurities in CO₂.
You can read additional info about the testing, including product used, materials, test protocols and results, reference gas cylinder information, impurity LOD results, CO₂ accuracy and repeatability, response time, tables and spectra in the application note Beverage-grade carbon dioxide purity analysis.
Additional Resources
- Application Note Beverage-grade carbon dioxide purity analysis
- Beverage-Grade Carbon Dioxide (CO₂) Purity Monitoring System
- Webinar: Real-time analysis of beverage-grade CO2 purity for quality assurance
- Video: See how Coca-Cola is using the MAX-Bev to create “the Perfect Sip
- Thermo Scientific™ MAX-Bev™ CO2 Purity Monitoring System
