Coffee is a delicate product. In order to prevent the oxidation of the coffee in portion packs, nitrogen gas is used during dosing until the capsules are sealed and the oxygen is removed. Due to cost efficiency – and to respect the ecological balance – it is important to keep the nitrogen consumption as low as possible while optimizing the shelf life and quality of the product. During a pilot project, Optima Consumer was able to reduce the nitrogen consumption of an older machine model to an impressively low level.
A well-known European manufacturer of coffee portion packs operates several OPTIMA CFL capsule making machines. The coffee portion packs are selling so well that it has been discussed to purchase another machine from their main supplier, Optima. Currently, nitrogen is supplied every one to two days to meet their demands.
Independent to this customer’s situation, Tobias Freiberger and Holger Frey report, that Optima started a retrofit project that examines the nitrogen flow on capsule machines. The objective is to change the gas supply systems in existing machines to the current state-of-the-art system.
The first step was to examine potential weaknesses of the system. With this in mind, Optima Consumer installed measuring plates into an existing filling machine. This allowed us to record and document the changing oxygen levels along the gas supply path. Initial cautious estimates were based on a savings potential of 10 to 15 percent nitrogen per machine which was achievable through retrofits.
New gas supply plates with a modified material combination and sandwich construction were an initial new “feature” developed by Optima. In addition to the "economy package", certain modules were adapted with a cup flushing device with an optimized flow profile, minimized spacing and a ring gas application. Due to this improvement, the desired residual container oxygen values can be regulated very precisely. Coffee portioning packs with a limit value of 0.1 percent residual oxygen (RO), one, two and five percent RO were packaged and stored for later evaluation and tasting.
The technical manager of the coffee capsule producer showed great interest in this modification. What are the potential nitrogen savings? The retrofit for the first pilot project at the customer’s site went very well and according to the technical manager the effects on the production are insignificant. Once again the modular design of the CFL machine proved to be a great advantage.
A company guideline targets a return of investment (ROI) within at least three years. Thus, the question of whether to execute a retrofit can meet this criteria. When calculating the ROI, the savings in nitrogen had to match the investment costs for the retrofit.
On the customer's multi-track pilot line, Optima significantly exceeded the expected value of 10 to 15 percent savings – and naturally, with identical residual oxygen values in the before and after comparison. Two positive side effects of the retrofit are; extremely uniform residual oxygen values are achieved across all machine tracks. In addition, the entire manufacturing process is now very clearly visible. Based on the results of the pilot project, the optimizations will be performed on the other Optima machines at the customer’s site within this year.
The technical manager at the customer’s company concluded; "Our expectations of nitrogen reduction were fully met, the concept of the new gas supply system convinced us. Together with Optima we will be making a number of additional improvements. All in all, the modular design and the high production quality of the systems are very help-ful. We also value the concerted and uncomplicated cooperation with Optima very much. During the daily operation, the intuitive usability and the software evaluations are especially important for us. For example, we know the number of rejects from each track and from each module. I would also like to mention the high qualifications of the Optima service technician. Fast and flexible service is very important to us."