Optimisation of the production process and creation of a new hopped flavour at BeKombucha

Details

Supervisors

Collin, Sonia

Faculty

Faculté des bioingénieurs

Degree label

Master de spécialisation en génie brassicole

Abstract

Kombucha is a fermented tea beverage that is either non-alcoholic or has low alcohol content. In recent years, it has gained significant attention and interest from both the scientific community and the general public due to its potential health benefits. The kombucha craze has spread all over the world, including here in Belgium. The Belgian kombucha market is still very small but is set to grow. Therefore, it's crucial for producers to stand out from the crowd with the products they offer, as well as ensuring a high-quality product to build up customer loyalty. This work was carried out during a six-month internship as a brewing engineer at BeKombucha, in order to improve BeKombucha's efficiency and create a new unseen flavour for the Belgian market. The three main objectives of this internship were to create a rigorous production protocol, to optimise the production process and site, and to develop a hopped kombucha flavour similar to an Indian Pale Ale (I.P.A.) beer. Various strategies were put in place to achieve them. The protocol was drawn up by following a production training session, taking meticulous notes, and finally transcribing everything into a document that became the production protocol. The production process and the site were optimised naturally by targeting areas for improvement based on the advice of Stéphane Evras (CEO) and my experiences in the field. Finally, the hopped kombucha was created using three hops added by dry hopping to the basic flavour Verbena-Melissa-Nettle kombucha. Various analyses of the Verbena-Melissa-Nettle base kombucha and the hopped kombucha were carried out to characterise the two beverages. As with the objectives, the results were diverse and varied. Firstly, the production protocol was created and used, and proved to be a winning tool for production and product quality. Secondly, various improvements and optimisations, both present and future, were implemented. Some of these were aimed at improving comfort in the workshop, while others concerned energy consumption, space management and machine repairs. Thirdly, the new hopped kombucha was created and proved to be a success. On the one hand, the hopped flavour was compared in a sensory analysis (88 untrained assessors) to the Verbena-Melissa-Nettle flavour. As far as we know, this sensory analysis is the largest sensory analyses ever carried out on kombucha. This analysis revealed that the assessors were able to differentiate between the two flavours and attributed significantly higher scores to the hop flavour for citrus and tropical fruit smell and aroma. In addition, the assessors rated the similarity with an I.P.A. of the hopped flavour at 3.59/5, which is an honourable score. The hopped flavour also has a much stronger bitter taste than the Verbena-Melissa-Nettle flavour. On the other hand, laboratory analyses showed that no significant differences were observed between the two flavours for most of the parameters measured, with the exception of total polyphenol content (higher in the hopped flavour), turbidity (lower in the hopped flavour) and bitterness (higher in the hopped flavour). Note that the aromatic compounds were not measured during these analyses (due to budget restrictions) but that there are very likely to be differences. In conclusion, this internship enabled BeKombucha to operate more efficiently thanks to the creation of the protocol and the various optimisations/improvements, and to benefit from a new hopped kombucha with pleasant flavours.