The brewing conditions optimization of Eucalyptus blended tea bags

Blended tea is a mixed herbal drink made from herbal plants’ leaves, roots, flowers, or stems. The blended tea that formulation has been reported in previous studies is composed of Eucalyptus leaves, cinnamon, and black tea. However, the optimum brewing conditions of Eucalyptus blended tea have not been studied. This study aims to determine the optimum brewing conditions of Eucalyptus blended tea using Response Surface Methodology (RSM) with Central Composite Design (CCD). This study used two factors, the loading per tea bag (2 g, 2.5 g, 3 g) and brewing time (2, 4, and 6 minutes). The parameters used were water-soluble extract content, color (L, a, b), and overall acceptability. The results showed that a weight of 2.48 g with a brewing time of 3.45 minutes was the optimum condition for brewing blended tea of Eucalyptus, cinnamon, and black tea.

Effect of Brewing Method on Quality Parameters and Antioxidant Capacity of Black Tea

Introduction: The traditional method for brewing tea in Turkey involves use of a two-vessel apparatus known as a “caydanlik.” The caydanlik allows for tea to be brewed for a longer time than typical brewing methods and involves introducing boiling water to tea leaves and steeping them in a teapot as the temperature declines over 15 minutes. In comparison, the typical tea brewing method used in other parts of the world involves steeping tea leaves in a single vessel teapot for 5 minutes. This study evaluated the effects of these two methods of brewing using two brands of tea. Results: Results of this experiment indicate that use of the caydanlik and the accompanying longer brewing time significantly changed key quality parameters and increased the antioxidant capacity of the brewed black tea beverage. Use of the caydanlik method resulted in significantly higher (P < 0.05) theaflavins, thearubigins, theabrownins, and total polyphenols in the resultant tea than in tea brewed in a traditional teapot. Additionally, analysis of color values of the brewed tea indicated the L and b-values were significantly (P < 0.05) lower in the caydanlik brewed tea while a and hue values were significantly higher (P < 0.05). However, chroma values were not significantly different (P < 0.05) between the two methods. Conclusions: In addition to influencing color, flavor and aroma, the brewing method also influenced the functional properties of prepared black tea. Use of the traditional two-vessel caydanlik for tea preparation increased concentrations of beneficial functional components in the tea.Keywords: Black tea, Caydanlik, Brewing, Camelia sinensis, ORAC, Total Phenolic Content

Pengaruh Persentase Penambahan Bubuk Daun Stevia rebaudiana Bertoni dan Lama Penyeduhan terhadap Karakteristik Minuman Kunyit Asam

The leaves of the Stevia rebaudiana Bertoni plant have glycoside compounds including stevioside and rebaudioside A which can be used as natural sweeteners to replace the artificial sweeteners such as aspartame. This sweetener has a sweetness level of 200-300 times that of sucrose, so it can be used as a non-calorie sweetener. One way to take advantage of these leaves is to brew directly on certain products. This study aims to determine the effect of the addition percentage and the duration of brewing stevia leaves on the characteristics of tamarind turmeric drink and determine the appropriate treatment to produce the best tamarind drink. This study used a randomized block design with two factors. The first factor is the percentage of addition of stevia leaves with 4 levels, namely 15, 20, 25 and 30%. The second factor is the length of brewing with 3 levels, namely 2, 3 and 4 minutes. The results showed that the treatment of the percentage of addition of stevia leaves had an effect on vitamin C levels and antioxidant activity of IC50. The treatment duration of brewing had an effect on the level of vitamin C, while the interaction between the percentage of addition and the duration of brewing had an effect on the ranking of sweetness and the preference for sour turmeric drink.. The addition of 15% stevia leaf powder by brewing for 2 minutes resulted in the best tamarind turmeric drink with the characteristics of IC50 namely 15.78 + 0.38 mg/ml, vitamin C level specifically 14.02 + 1.15 mg AAE/g extracts and ph was 3.33 + 0.18 and the sweet and hedonic taste ratings are slightly sweet and slightly likable, respectively. Keywords : Brewing time, stevia addition, turmeric-tamarind drink

The Effect of Brewing Process Parameters on Antioxidant Activity and Caffeine Content in Infusions of Roasted and Unroasted Arabica Coffee Beans Originated from Different Countries

Coffee is one of the most often consumed beverages almost all over the world. The multiplicity of beans, as well as the methods and parameters used to brew, encourages the optimization of the brewing process. The study aimed to analyze the effect of roasting beans, the brewing technique, and its parameters (time and water temperature) on antioxidant activity (determined using several in vitro methods), total polyphenols, flavonoids, and caffeine content. The infusions of unroasted and roasted Arabica beans from Brazil, Colombia, India, Peru, and Rwanda were analyzed. In general, infusions prepared from roasted beans had higher antioxidant activity and the content of above-mentioned compounds. The hot brew method was used to obtain infusions with a higher antioxidant activity, while the cold brew with higher caffeine content. The phenolic compound content in infusions prepared using both techniques depended on the roasting process. Moreover, the bean’s origin, roasting process, and brewing technique had a significant effect on the tested properties, in contrary to brewing time and water temperature (below and above 90 °C), which had less impact. The results confirm the importance of coffee brewing optimization.

Determination of Aluminium Concentrations in White Tea Samples

Objectives Tea is a popular drink around the world. To date several studies showed that tea might be exposed to toxic chemical contaminants. Aluminium (Al) is one of the metals contaminating tea. This study aimed to evaluate the Al concentrations in white tea. Methods Commercially available tea samples were brewed in 5 different teapots, consisting of aluminium, copper, glass, steel and porcelain materials for 5, 10, and 15 minutes. Al concentrations in tea samples were determined by high-performance liquid chromatography with fluorescence detector. The hazard quotient (HQ) was calculated according to 70 kg body weight and 10 g/day tea consumption. HQ value less than 1 (HQ ˂ 1) is considered safe. The relationship between tea types, teapot type and brewing time factors were determined using 3-way ANOVA test. Bonferroni correction was applied for multiple comparisons. Results Al concentrations in white tea samples were in the range of 181.97 ± 11.88 – 352.45 ± 5.86 µg/L. Both teapot type (p &lt; 0.001) and brewing time (p &lt; 0.001) significantly influenced Al concentrations in tea samples. The interaction between teapot material and brewing time was statistically significant (p &lt; 0.001). The hazard ratio was less than 1 for white tea infusions except for one sample, which was brewed in glass teapot for 15 min. Conclusions It was found that white tea consumption might be a potential risk factor for Al exposure. Funding Sources None declared.

Influence of Various Factors on Caffeine Content in Coffee Brews

Coffee brews are one of the most popular drinks. They are consumed for caffeine and its stimulant properties. The study aimed to summarize data on the influence of various factors on caffeine content in brews prepared with different methods. The study was carried out using a literature review from 2010–2020. PubMed and Google Scholar databases were searched. Data on caffeine content was collected by analyzing the following factors: the influence of species, brewing time, water temperature, pressure, degree of roast, grinding degree, water type, water/coffee ratio as well as other factors (such as geographical origin). To sum up, converting caffeine content to 1 L of the brew, the highest content is that of brews prepared in an espresso machine (portafilter), with the amount of 7.5 g of a coffee blend (95% Robusta + 5% Arabica), and water (the volume of coffee brew was 25 mL) at a temperature of 92 °C and a pressure of 7 bar, but the highest content in one portion was detected in a brew of 50 g of Robusta coffee poured with 500 mL of cold water (25 °C) and boiled.

Analysis of Microbial Diversity and Variation Law During Xiaoqu Baijiu Fermentation using High-throughput Sequencing Technology

In this study, high-throughput sequencing (HTS) was used to compare and analyze the microbial diversity and variation law during the brewing process of xiaoqu Baijiu. The results showed that 34 phyla, 378 genera of bacteria and 4 phyla, 32 genera of fungi were detected. At the phylum level, Firmicutes, Proteobacteria, Bacteroidetes, Ascomycota and Bacteroidetes were the dominant groups. During the brewing process of xiaoqu Baijiu, the dominant bacteria were Weissella and unidentified Rickettsiales 2 days before brewing and Lactobacillus 3 days after brewing until the end of brewing. The dominant fungi were Rhizopus, Saccharomyces and Issatchenkia. The relative abundance of Rhizopus decreased with the extension of brewing time, while the relative abundance of Saccharomyces increased and became the dominant bacteria after the second day of brewing. This study revealed the diversity and variation of microbial community in the brewing process of xiaoqu Baijiu, and provide theoretical support and lay the foundation for future study on the contribution of microbial metabolism during brewing of xiaoqu Baijiu, thereby promote the development of xiaoqu baijiu industry.