Bar Top Stoppers - Follow the Guide!

For some time now, a number of Cetie members directly concerned by the subject of bar top stoppers have suggested that Cetie should initiate work in this area.
It is indeed a stoppering system for which few reference documents currently exist, and the underlying message is that this situation gives rise to diverging interpretations and litigation that are detrimental to the overall value chain. Wider consultation within Cetie and among our network of contacts confirmed the interest to set up a Cetie Working Group to produce specific technical reference documentation. This Working Group recently held its launch meeting, which confirmed the prospect of a dynamic and effective action on this worthwhile subject. Here is some feedback on this meeting. As with the creation of any new Cetie Working Group, the agenda kicked off with two essential initial actions, namely electing a Chair and determining the Group's scope of action.

The Group duly elected Crisóstomo Joachim Ribeiro Ferreira (Amorim y Irmaos) as Chair, given his longstanding professional experience in stoppers and their utilisation in various countries and markets. He is also familiar with how Cetie Working Groups function and the role of Chair. The discussion on the scope of action of the Working Group brought forth some of the essential characteristics of stoppering using bar top stoppers, including manual opening and reclosing without using a tool, and combined use with an overcap. It was decided to consider only stoppers that ensure sealing through contact between the stopper body and the interior of the bottle finish. The Group will focus on both the component specifications and best practice for their implementation.
With regard to the overcap, it was pointed out that as well as acting as a tamper-evident feature and a medium for carrying visual identity and excise stamp, it can contribute to mechanically securing the stopper during transportation and until the bottle is first opened.
This type of stoppering is in fact only suitable for "still" non-carbonated products, but the pressure in a stoppered bottle can nevertheless rise due to temperature increases, which cause thermal expansion of the product.
The main markets for bar top stoppers concern beverages with a relatively high alcohol content, which increases the coefficient of expansion and therefore the pressures reached. In this respect, the practical difficulty of ensuring compliance with maximum temperature limits during transportation, particularly in export situations, was pointed out.
The bottling conditions are therefore all the more important, and especially the need to comply with the necessary headspaces according to the types of product, as recommended in Cetie data sheet FS07.
 

Although bar top stoppers are sometimes used for edible oils or vinegar, the main markets concern spirits, liqueurs and muted wines (liqueur wines, fortified wines, etc.).
The expertise of the Group as it is currently composed lies above all in these latter markets. It was therefore decided to initially limit the scope of the Group to alcoholic beverages, but with the possibility of extending it at a later stage to these other markets if the demand arises and the necessary expertise is available.
The Group also confirmed that its work would be centred on the production of a Bottling Guide, already identified as being No. 14 in the series of Cetie Guides.
The general structure of this guide follows the established model that has recently been streamlined during the ongoing revisions of other Bottling Guides.
It was thus possible during the meeting not only to establish a framework for Guide No. 14 "Bar Stop Stoppers", but also to start drawing up the first sections on the general requirements, also based on texts of the Guides undergoing revision. This is particularly the case with the scope of the document, also drawn upon the basis of that of the Working Group itself.
During the discussions, the Group carried out the important task of examining the existing reference documents that had been identified beforehand.
These would effectively be limited to just two Afnor standards.
The first document, standard NF H35-081 "Stoppering with Bar Top Stoppers of 27, 29, 34 mm", the last revision of which dates from 2008, is an interesting and atypical standard because it describes the three constituent components of this system, i.e. the bar top stopper, the glass bottle finish and the overcap.
It nevertheless turns out that this standard only partly covers the various cases found on the market today.
More specifically, the development of different stopper body materials can affect the definition of the internal profile of the finish, which moreover is only specified in general terms (cylindrical or in the form of an "A" extending over 15 mm).
 

The second standard, NF H35-027, which describes the "Porto finish" for a bar top stopper, is even older.
Nonetheless, it has not been revised and it does not even define the internal profile, although this would be necessary. The work on the Guide will therefore no doubt lead to the updating of these references, or the creation of new specifications. It would also be worthwhile standardising the specific test methods, such as the “pop-up” test for filled and stoppered bottles.
Dates have been set for the next two work and discussion meetings, with contributions to come from the participants on the description and characteristics of the various components, verifications to make on these and specific conditions of storage, to be incorporated in the structure of Guide No. 14, which is already taking form as a first draft.

A Guide forging ahead … to be followed!

If you wish to take part in this Group or simply tell us about any experience you consider worthwhile sharing in this context, please contact us: contact@cetie.org.