The Best Headspace Analyzers (the Ultimate Guide)
What is Headspace Analysis?
Headspace is the term used within the food industry to refer to the residual air that is within a closed or sealed packet. The air that remains in the packet is sometimes normal air. To extend the shelf life of food, air is not used, but a mix of gases is used instead.
Typical headspace gases include nitrogen (N2), carbon dioxide (CO2) or carbon monoxide (CO2).
Headspace Analysis is the technical test undertaken to determine gas levels with the food packaging. Performing this test accomplishes the following:
- Ensures the food packaging production line is operating as expected.
- Provides a quantitative quality control key figure of merit.
- Ensures the packaging is sound and not compromised with pin holes or poor adhesion.
What is Modified Atmosphere Packaging (MAP)?
When air is replaced with a gas mix (i.e CO2, N2 or CO) during food packaging, this process is called Modified Atmosphere Packaging (MAP).
MAP technology extends shelf life by reducing oxidation and spoilage of perishable food and beverage products.
MAP is commonly used in a variety of foods. Produce foods such a packaged broccoli, meat products such as packaged sausages and dry products such as nuts and coffee are only a few examples.
Why do foods require MAP?
In most food packaging applications, an important objective is to extend shelf life. This can be accomplished by introducing a unique gas or gas mixture into the food packaging to:
- Reduce oxygen to reduce rate of oxidization.
- Reduce growth of bacteria or mould.
- Reduce food degradation via reducing lipolysis.
- Reduce breakdown of food proteins.
- Reduced other physicochemical deterioration processes.
Extending shelf life also reduces food waste, enables for more customer and retailer versatility and ultimately improves the freshness of food over a extended period of time. All in all, extending the food life provides better value for money to the end customer.
What is a Headspace Analyzer?
A Headspace Analyzer is sometimes called a MAP analyzer or a Food Packaging Analyzer. The analyzer has a build-in pump that draws a gas sample from a packaged food product using a small probe or syringe.
The gas in then passed onto sensors that reside within the analyzer. The sensor output voltage changes based on the gas concentration and then based on curve fitting algorithms the analyzer determines the concentration of gas.
The most common Headspace Analyzer is an Oxygen Headspace Analyzer. In most cases, food packets undertake a nitrogen flush, to remove as much oxygen as possible. Hence, analyzing oxygen concentration is very important and one of the most common Headspace Analyzers tests to undertake.
What is a MAP Analyzer?
A MAP analyzer is also sometimes called a Modified Atmosphere Packaging Analyzer. It is synonymous for a Headspace Analyzer and even sometimes called a Food Packaging Analyzer. Dont get confused, they all refer to the same equipment.
Which gases are used for MAP and Headspace?
Typical gases used for headspace is carbon dioxide (CO2), nitrogen (N2) and carbon monoxide (CO). Depending on the food and packaging type, different gases and their ratios will be altered. These differences will effect the physicochemical deterioration that takes place, such as oxidation, lipolysis, and proteolysis.
Examples of packaged foods and typical MAP gas compositions:
Fresh Fruit and Vegetables
- Gas Mix of 90% N2, 5% O2, 5% CO2
- Cottage Cheese = 100% CO2, 0% O2
- Provolone = 30% CO2 with 60% N2 and 0% O2
- Cooked Meat such as Burger Patties = 70% N2 with 50% CO2 and 0% O2
- Raw Meat such as Beef and Pork = 70% O2 with 30% CO2 and 0% O2
- Coffee and Nuts: 100% N2 and 0% O2
How do I perform a Headspace Analysis?
Performing a headspace Analysis is straightforward. The test process goes something like this:
- Ensure you have your needle, filter and tubing attached to the MAP analyzer.
- Ensure the Analyzer pump is operational.
- Ensure the Analyzer is calibrated. For example, if detecting O2 ensure the O2 is reading 20.90%. CO2 is reading <0.1% and CO is reading 0%.
- Place a septa on the location on the food packaging.
- Place the needle through the septa and into the package. Turn the pump ON (in not already ON) and take a gas sample
- As the sample is taken, the packaging will shrink since gas is being drawn out of it.
- Take note of the gas concentration on the analyzer. Once the levels have stabilized, take your data recording.
An example Headspace Analysis is shown below using coffee packaging.
What are the best Headspace Analyzers?
- Forensics Detectors Headspace MAP Analyzers
- Systech Illinois MAP Analyzers
- Mocon Headspace MAP Analyzers
- Novatech Food Packaging Analyzers
- Quantek Instruments Food Package Testing
- Bridge Analyzers MAP Analyzers
- AGC MAP Analyzers
What are the most important Headspace Analyzer considerations?
- Gas Target: Trivial yet important. Define which exact gases you wish to measure. Is it a single gas such as O2 or dual gases such as O2 and CO2?
- Detection Range and Resolution: You also want to make sure you purchase an Analyzer with the correct detection range and resolution. For example, when detecting O2, are you targeting to check residual O2, which is very low amounts or high amounts as required for meat products? For residual oxygen you need to ensure complete zero oxygen, in that case, you would prefer to obtain a gas analyzer with 0.01% (100ppm) resolution.
- Size and Mobility: Traditionally, Headspace Analyzers have been build as desktop instruments. With the advent of faster and smaller electronic components many new handheld version are available.
- Accessory Options: This is important as it adds to the ongoing costs. Check if any proprietary accessories such as filters, septas, needles are required that may add to your operational costs, or if generic components can be substituted to help reduce ongoing costs.
- Calibration: Understand that calibration requirements of your analyzer. Ensure if can be calibrated by you, otherwise increased costs to ship and have it calibrated by a 3rd party will increase operational costs
- Sensor Lifetime: Ensure you understand sensor lifetime and sensor replacement options as all sensors have a finite lifetime.
What are Headspace Analyzer Accessories?
A headspace analyzer requires accessories to perform a headspace analysis.
- Needles: Needles comes in all different shapes and sizes. Ensure your needle is a generic type and you can purchase different gauges, just in case your application requires something unique. Ensure the needle is not blocked by food debris, package debris or septa debris.
- Filters: A filter is important to protect your analyzer from any food particles or packaging debris that may be sucked while undertaking a MAP analysis.
- Septa: These are your most high volume consumable. The septa is a rubber or foam pad that is used to ensure a tight fit when the needle penetrates the packaging. This ensures no air gets into the package and no gases inadvertently escape.
- Tubing: Ensure your tubing is as short as possible so that a faster headspace analysis can take place. Ensure the tubing is food grade and has good flexibility for easy usability such as food grade silicone tubing.
Why are Headspace Analyzers so expensive?
Headspace analyzers are so expensive because they include expensive components. The hardware consists of a computer with a power microprocessor to analyze the sensor information and translate that information into meaningful gas calibrated concentration values. The majority of the analyzer cost is made up of the actual gas sensor which is a small electronic device that changes electronic output signal based on the gas concentration it is detecting.
Do Headspace Analyzers require calibration?
Yes they do. All headspace Analyzers require period calibration. At Forensics Detectors we recommend every 6 to 12 months.
Headspace Analyzer calibration is a technical procedure undertaken every 6 to 12 months to ensure your gas detector is functioning accurately. Over time, gas detectors and their respective sensors degrade, some faster than others, and the only way to ensure accurate readings is via gas calibration.
Gas calibration involves exposing your gas analyzer to a traceable concentration of test gas concentration. Doing so in a controlled environment and using certified gas from the National Institute of Standards and Technology (NIST) adjusts the calibration curve of your gas detector to read true and accurate.
A Headspace Analyzer is an important instrument for most food companies that are manufacturing and packaging various foods. Headspace analyzers are technical instruments that require some care and maintenance as they are a analytical tool with sensitive sensors within them. A Headspace Analyzer provides the food packer with quantitative gas concentration data within a food packet so that it meets the expected quality control thresholds.
About The Author
Dr. Koz is the President of FORENSICS DETECTORS where the company operates from the scenic Palos Verdes Peninsula in Los Angeles, California. He is a subject matter expert on gas sensor technology, gas detectors, gas meters and gas analyzers. He has been designing, building, manufacturing and testing toxic gas detection systems for over 20 years.
Everyday is a blessing for Dr. Koz. He loves to help customers solve their unique problems. Dr. Koz also loves spending time with his wife and his three children going to the beach, grilling burgers and having a cold beer.
Read more about Forensics Detectors here.