Sensory Profile of Kombucha Brewed with New Zealand Ingredients by Focus Group and Word Clouds

Abstract

Kombucha is a yeast and bacterially fermented tea that is often described as having an acetic, fruity and sour flavour. There is a particular lack of sensory research around the use of Kombucha with additional ingredients such as those from the pepper family, or with hops. The goal of this project was to obtain a sensory profile of Kombucha beverages with a range of different ingredients, particularly of a novel Kombucha made with only Kawakawa (Piper excelsum) leaves. Other samples included hops and black pepper. Instrumental data were collected for all the Kombucha samples, and a sensory focus group of eight semi-trained panellists were set up to create a sensory profile of four products. Commercially available Kombucha, along with reference training samples were used to train the panel. Kawakawa Kombucha was found to be the sourest of the four samples and was described as having the bitterest aftertaste. The instrumental results showed that the Kawakawa Kombucha had the highest titratable acidity (1.55 vs. 1.21–1.42 mL) as well as the highest alcohol percentage (0.40 vs. 0.15–0.30%). The hops sample had the highest pH (3.72 vs. 3.49–3.54), with the lowest titratable acidity (1.21), and, from a basic poll, was the most liked of the samples. Each Kombucha had its own unique set of sensory descriptors with particular emphasis on the Kawakawa product, having unique mouthfeel descriptors as a result of some of the compounds found in Kawakawa. This research has led to a few areas that could be further studied, such as the characteristics of the Piperaceae family under fermentation and the different effects or the foaminess of the Kawakawa Kombucha, which is not fully explained.

Changes in the chemical compositions and biological properties of kombucha beverages made from black teas and pineapple peels and cores

“…Similar results were also observed for kombucha fermented using fruit juices, such as apples, pomegranates, red grapes, and sour cherry juices, in which the final ethanol concentrations were 0.82%, 0.84%, 0.59%, and 0.67% (v/v) ethanol, respectively 93 . Compared with the current study, low values (0.30–0.60%) 94 , 95 and high values for the ethanol content (1.14–5.83%) 7 , 88 , 96 were also reported, which could be due to the differences in the raw materials used, the fermentation conditions, the sources and microbial compositions in the kombucha SCOBY, and the kombucha supplementing materials 97 . Regarding the health benefits of the kombucha, a low level of ethanol has a harmless influence on human health, similar to low-alcohol beverages in which the ethanol contents range from 0.05 to 1.20% 93 .…”

Fermentation with Tea Residues Enhances Antioxidant Activities and Polyphenol Contents in Kombucha Beverages

“…The sensory panel analysis of kombucha beverages was performed according to the literature [ 15 , 24 ]. The kombucha beverages were scored by seven graduate students and one professor (23–58 years old) from the Department of Nutrition, School of Public Health, Sun Yat-Sen University.…”

Bacterial Nanocellulose Derived from Banana Leaf Extract: Yield and Variation Factors

“…These assimilate the glucose present in the medium to carry out their various metabolic processes [97,98]. Therefore, due to these biochemical and metabolic processes, acetic and gluconic acid are generated, which lowers the pH of the fermentation medium [99][100][101][102]. In this sense, the lowest acceptable pH value should not be less than 3 [99].…”

“…Therefore, due to these biochemical and metabolic processes, acetic and gluconic acid are generated, which lowers the pH of the fermentation medium [99][100][101][102]. In this sense, the lowest acceptable pH value should not be less than 3 [99]. Figure 4 shows the increase in pH at different fermentation times.…”