Dylan Shaw - Managing Director
Firstly, I’ll start by saying I’m no expert in microbiology, however we do have a lot of experience in drinks bottling markets globally.
By way of an introduction, I am the Managing Director of Alphabond Technologies and have been involved in this industry for several years. As a company, we have gained a lot of knowledge around large global companies bottling anything from Coca Cola to Cognac to fizzy water.
Our first exposure to the issue of mould on bottle labels was a number of years ago when one of the large sparkling water producers had issues with mould growth on a bottle affecting a number of pallets of their product. With a thorough investigation we found that this occurs when the "right" conditions in the bottling hall, meet with fungi-containing materials (cardboard, paper etc.) – it can be a one-off issue but becomes repeatable if changes are not made to tackle it.
Recently it was brought to our attention again when a major brand had issues with mould growth on beer labels, with microbiologist help and after significant testing on a variety of label, bottle and adhesive combinations, we concluded with this;
- Most paper labels and cardboard naturally contain quantities of fungal/mould spores, these are ready to spring into action as soon as warm, humid conditions allow for fungal growth.
- Trapping the product (i.e. bottles) in film (i.e. pallet wrap) in the above conditions, accelerates spore growth as the bottles and boxes cannot 'breath'.
- Standard types of wet glues are not suitable to resist mould growth when it occurs and can even encourage it as they contain natural ingredients, which spores thrive on.
Lengthy testing in the laboratory enabled us to replicate results in different conditions:
Summary of our findings:
- Use a wet glue which has special fungicide treatment in to ensure the risk of mould growth is minimised – check your current supplier is doing this already as most are not.
- Use perforated pallet, tray and shrink wrapping to allow the product to breath – this reduces the chance of increased humidity.
- Measure the temperature and humidity in bottling conditions so that special care is taken when it is high.
- If some stock is affected, quarantine the rest of your stock (ideally off-site) to avoid cross contamination.