The Sensory Quality and the Physical Properties of Functional Green Tea-Infused Yoghurt with Inulin

Abstract

The purpose of this study was to investigate the influence of the addition of inulin (3%, 6% and 9%) to green tea-infused set type yoghurt on its sensory quality and physical properties. Yogurts were made by combining green tea with milk and inulin and inoculated with freeze-dried starter cultures YO-122. Incubation was conducted at 43 °C for approximately 4.5 h until a pH value of 4.5–4.6 was achieved. For the prepared yoghurts, a panel of experts (n = 10) was selected, characterized 35 attributes and conducted a sensory quality assessment of these yoghurts using the Quantitative Descriptive Profile method. Additionally, instrumental analyses such as yield stress, adhesiveness, firmness, physical stability and color parameters were also carried out. The use of green tea infusion increased the perception of green tea flavor, bitterness, astringency, dark color of the yoghurt and the existing whey, which worsened the overall sensory quality of the yoghurt. The addition of inulin (9%) to the green tea yoghurt, increased the perception of sweet, peach flavor and aroma and improved the firmness of the yoghurt while reducing the perception of sour taste, which improved the sensory quality of the yoghurt. Both inulin and green tea affected the physical properties of the yoghurts, causing an increase in the yield stress (43%, and 20%, respectively) and deteriorated the stability of the yoghurts. Green tea affected the color of the yoghurts, causing the lightness to decrease. The L* parameter decreased from 89.80 for the control sample to 84.42 for the green tea infused yoghurt. The use of infused green tea in yoghurt production makes it necessary to use ingredients that will neutralize its adverse effects on sensory quality and physical parameters of yoghurt, and such an additive can be prebiotic fiber–inulin at a concentration of 9%.

Variations in physicochemical characteristics, antioxidant activity, phenolic and volatile profiles, and sensory attributes of tea-flavored Chardonnay wine during bottle aging

“…, chlorophyll, carotenoids) accumulated throughout the aging process. 22 The color variation in black tea Chardonnay may be due to the decreased content of brown-colored phenolic compounds ( e.g. , thearubigins, theaflavins) from black tea during aging.…”

“…For the green tea Chardonnay wines, the darker wine color and the prominent shifting toward yellowish and redness might be due to the autoxidation products of tea polyphenols and the infused tea colorants (e.g., chlorophyll, carotenoids) accumulated throughout the aging process. 22 The color variation in black tea Chardonnay may be due to the decreased content of brown-colored phenolic compounds (e.g., thearubigins, theaflavins) from black tea during aging. In the model wines, the L*, a* and b* values experienced the similar pattern of changes as green tea Chardonnay wines with the increasing aging period (Fig.…”

Dairy Product Consumption and Preferences of Polish and Taiwanese Students—NPD Case Study

“…The answers obtained to the above research questions on the consumption and preferences of dairy products (especially fermented products) among the surveyed students from Poland and Taiwan showed differences and similarities in preferences and consumption of these products between the students. The obtained research results made it possible to direct the next phase of project research, aimed at developing a functional yogurt with high sensory quality and corresponding to consumer preferences [9,18,55].…”

“…Then, the method was improved and an innovative dairy product based on tea infusion was developed, and the results of this experiment were published [9]. Improvements to the product continued with the addition of inulin as a probiotic and texturizing substance, and these results were also published [18,55]. This research is also a case study of an interdisciplinary approach to the design process, where researchers from two different countries joined forces to create a common food product.…”