Antares Vision Group: Laser absorption spectroscopy for quality control in beverage sector

An innovative laser absorption spectroscopy application developed by Antares Vision Group with FT System Technology allows measuring of the pressure and concentration of certain gases in the headspace of bottles in a non-destructive and non-invasive way to check leaking caps and monitor the production process.

Laser absorption spectroscopy is an optical technique for measuring the presence of certain gases. To do this, it uses a specific physical property that certain molecules in the gaseous state have, which allows them to absorb light.

The highly monochromatic, tunable emissive characteristics of new solid-state lasers allow this property to be exploited in order to measure gas presence (O2, CO2, etc.) in an extremely accurate way, and to measure partial and total pressure inside partially transparent, closed containers and various types of containers made of different materials, in different colours and with varying thickness and optical characteristics.

Which parameters can be measured with laser absorption spectroscopy?

With laser absorption spectroscopy technology, the concentration of a certain gas (O2, CO2, etc.) in a closed container can be measured, as well as the partial pressure of this gas and the total pressure caused by all the gases.

It is possible to apply this technology with both laboratory instruments, with which the concentration parameters of a gas in the headspace of the container can be measured non-destructively and even repeatedly over time on the same sample, as well as in-line to measure 100% of the production process.

In in-line checks, the laser beam is positioned at the right level to pass through the bottle headspace and measures the gas presence and pressure in an extremely accurate way.

Which inspections are possible, and where is possible to apply this technology?

Laser absorption spectroscopy allows checking for leaking caps or valves, as in the case of kegs, and monitoring N2, CO2 and O2 presence in different types of closed products.

Here are some examples of successful applications:

• In soft drinks for nitrogen and vacuum level monitoring liquid nitrogen is dosed in drops to pressurise the bottle, which makes it possible to reduce the amount of plastic used. Measuring pressure in-line, after 100% of the bottles have been capped, offers numerous advantages, including the certainty of not having any deflated containers or containers with leaking caps when palletising them. In addition, the nitrogen dosing process can also be monitored, and feedback can be sent to the dosing system itself, with considerable reductions in nitrogen consumption. Vacuum measurement is used in hot-filled products to control leaks and the level of vacuum in each container, giving a complete process control.
• In still wine for oxygen internal presence and pressure. The control is performed immediately after capper; oxygen presence check allows to find inerting procedures malfunctions during the filling; internal pressure check monitors if the vacuum level is correct so as to avoid possible high cork or the creation of channels were O2 to come inside the bottle. A continuous production process checking facilitates immediate action in case of inefficiencies, avoiding a defective bottling of big amounts of wine that affect organoleptic qualities and properties.
• In classic method sparkling wine through pressure check, our technology has allowed producers to monitor 100% of the bottles at the end of the second fermentation process, before uncorking them for the disgorging process. In this way, the highest quality bottles can be selected over those in which refermentation caused some problems. As a result, product quality can be guaranteed and monitored, and the part of production where some problems occurred is not wasted either, which means that the product can be reworked and recovered. In this field, laboratory instruments that spot-check bottle fermentation in a non-destructive way find application.
• In bottled beer and kegs. Internal pressure is monitored so as to find possible leaking caps after the pasteurisation phase. Precision and accuracy of measurement allow for finding micro-leaks and partial leaks that may appear only inside the pasteuriser. With this technology, acoustic and visual limits are overcome, avoiding false rejects. In the case of kegs, CO2 leakage from the valve is found. The machine sniffs the surroundings of the valve and brings the gas sniffed into a measuring chamber where through the laser absorption spectroscopy CO2 presence is found. The presence of the gas, even at low concentrations, indicates that there is a leak or a micro-leak.

Benefits for the market

Laser absorption spectroscopy’s innovative application in the beverage industry has brought many benefits both in terms of process monitoring and leaking caps detection. This allows producers to guarantee the quality and organoleptic characteristics of the product through the optimisation of all critical stages of the process, like inertisation and fermentation, and to avoid the production of thousands of compromised quality bottles. This innovative inspection by Antares Vision Group guarantees product quality, protects the brand and prevents inefficiencies in the bottling process.