Thermal expansion of bottled wines and brandies

: validation of the bottle’s expansion chambers

Abstract

The thermal expansion of bottled beverages is a very important parameter when choosing the bottle and the closure system, for a particular product. If this factor is overlooked or poorly studied, problems can occur during the transport and storage, especially during the warmer months. The bottle and closure’s dimensions must guarantee a free space between the closure and beverage level, allowing the beverage’s volume increase caused by temperature variations. This free space is referred to as expansion chamber (EC). This thesis focused on the study of the thermal behaviour of several alcoholic beverages (red table wine, ruby Porto wine, brandy and brandy old aged) and on the validation of the EC used currently by the company for these beverages. A detailed study on the internal profile of the bottleneck allowed the development of a precise calculation of the EC for each sample pair bottle-beverage. The results were compared with the method currently used by the company for the same purpose. Significant differences were found for the red wine samples but not for the other samples. Storage and transport simulations, with varying temperature, were carried out to observe the behaviour of the products when exposed to high temperatures. It was concluded that the EC for the Porto wine, brandy and brandy old aged were well defined. The red wine samples presented defects that made it impossible to complete the simulations, demonstrating that those EC need to be revised. Experiments were performed to determine the volumetric coefficient of thermal expansion (CTE). The following values were found: 4.02×10 -4 °C-1, 5.11×10 -4 °C-1, 6.35 ×10 -4 °C-1 and 7.78 ×10 -4 °C-1 respectively for red wine, Porto wine, brandy, and brandy old aged. Overall, the results permitted the development of predictive model for the beverage level as a function of the temperature. Knowing the inner profile of the bottleneck, the closure’s dimensions, the filling level, and the CTE, it was possible to determine the beverage level for a given temperature. This model was used to propose a solution for the problem observed in the red wine samples during the simulations.

Date of Award	28 Jul 2022
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Maria de Fátima Poças (Supervisor)