For the processing of our corks we use up to date technique.
Our production
Entry
Korkindustrie Trier specializes in the import of unwashed raw corks of high quality. Purchasing from several suppliers at the same time makes it possible to select the best qualities. After the first tests at reception, the corks are kept in a dry storeroom until they are required for processing.
Washing
The corks are washed in our production plant in Trier, applying a very gentle washing procedure with lots of water. This way, our customers can be certain that
- the tannins are considerably reduced
- the surface of the cork is thoroughly cleaned from dust and dirt
- the cell structure of the cork is only minimally damaged during the washing process
- the visual aspect of the cork is not altered by color additives during washing.
The washing is done in a unit which combines the washing, the centrifuging and the drying. The final humidity of the corks can be adjusted so that the corks leaving the washing machine can be guaranteed to be below 8%, the critical level for microbiological growth.
Considerations to import washed corks were rejected for the following reasons:
- washing procedures and washing agents vary considerably from one supplier to the other
- color additives during washing simulate a uniform sorting
- aggressive washing procedures, for instance strong bleaching, attack the outer cells of the cork
- the use of non-approved washing agents cannot be excluded.
Surface Treatment
The surface treatment consists of 2 phases, an initial one to improve the impermeability of the cork to the wine and a final one to adjust the extraction force. This sophisticated procedure is possible thanks to a fully automated treatment unit specially developed for Korkindustrie Trier. The impermeability of natural corks maintains the wine at the very end of the cork, and ensures an excellent seal in the bottleneck.
Sorting
Each cork lot is subject to a final hand sorting by trained employees. This makes it possible to balance variations within the raw material and to eliminate major defects.
Printing
The corks are printed on state-of-the-art printing machines according to the customers' specification. Korkindustrie Trier has the equipment to make its own dies and is therefore very flexible to meet special requests without delay.
Packaging and Shipping
The corks are packed in PE-bags of 1.000 corks each (dimensions 44,5 x 24 mm), including an injection of a determined quantity of SO2. The TOP-corks can be packed in gas-tight aluminium bags upon request. Customers receive our corks in solid cardboard boxes by various means of transport.
Quality Assurance
Comprehensive entry and process controls enable us to monitor the quality of natural corks. On the basis of large random samples taken from homogenized cork batches, exact evaluations can be made with respect to the product quality. For sensory controls, for instance, 200 corks – and in case of doubt considerably more – are taken out of each production batch (50.000 corks) for analytical testing.
By printing the order number on the corks, all data can be traced back to the original batch.
Out of the different lots available, Korkindustrie Trier selects the best ones for its customers. To achieve this, the company’s two GC/MS units are used to detect cork compounds which can lead to alterations in wine. The objective is to check as many relevant sensory compounds as possible on the random samples in order to avoid a negative influence on the wine.