scholarly journals The Joint Use of Electronic Nose and Electronic Tongue for the Evaluation of the Sensorial Properties of Green and Black Tea Infusions as Related to Their Chemical Composition

2013 ◽  
Vol 04 (06) ◽  
pp. 605-615 ◽  
Author(s):  
Susanna Buratti ◽  
Antonella Casiraghi ◽  
Paola Minghetti ◽  
Gabriella Giovanelli
Keyword(s):  
Chemical Composition ◽  
Electronic Nose ◽  
Electronic Tongue ◽  
Black Tea ◽  
Tea Infusions ◽  
Green And Black Tea

scholarly journals A predictive approach to the antioxidant capacity assessment of green and black tea infusions

2020 ◽  
Author(s):  
Małgorzata Muzolf-Panek ◽  
Anna Kaczmarek ◽  
Anna Gliszczyńska-Świgło
Keyword(s):  
Data Mining ◽  
Antioxidant Activity ◽  
Antioxidant Capacity ◽  
Black Tea ◽  
Multivariate Adaptive Regression Splines ◽  
Total Phenolic ◽  
Data Mining Techniques ◽  
Tea Quality ◽  
Tea Infusions ◽  
Green And Black Tea

AbstractContemporary consumers drink significant amounts of tea because of its health–benefits mainly associated to the presence of polyphenols with high antioxidant activity. Therefore, the information how to obtain tea infusion of the highest quality, i.e. with high antioxidant capacity is needed. In this study, the various models for the prediction of total polyphenols and antioxidant activity of green and black tea infusions were developed and compared. Three mathematical equations: Spiro’s, Peleg’s and logarithmic, and two data mining techniques: multivariate adaptive regression splines (MARS) and artificial neural networks (ANNs) were used to build the predictive models. The results obtained show that Spiro’s model could be used for the prediction of green tea quality expressed as total phenolic content or the antioxidant activity (determination coefficients above 0.99), whereas Peleg’s model is more suitable for black tea quality prediction (determination coefficients above 0.99). Data mining techniques (MARS and ANNs) enable to create models fast and of simple application with very good acceptability (determination coefficients above 0.99).

Estimation of black tea quality by analysis of chemical composition and colour difference of tea infusions

2003 ◽  
Vol 80 (2) ◽  
pp. 283-290 ◽  
Author(s):  
Yuerong Liang ◽  
Jianliang Lu ◽  
Lingyun Zhang ◽  
Shan Wu ◽  
Ying Wu
Keyword(s):  
Chemical Composition ◽  
Black Tea ◽  
Colour Difference ◽  
Tea Quality ◽  
Tea Infusions

scholarly journals Magnetic Field Extraction Techniques in Preparing High-Quality Tea Infusions

2018 ◽  
Vol 8 (10) ◽  
pp. 1876
Author(s):  
Maria Tarapatskyy ◽  
Grzegorz Zaguła ◽  
Marcin Bajcar ◽  
Czesław Puchalski ◽  
Bogdan Saletnik
Keyword(s):  
Magnetic Field ◽  
Amino Acids ◽  
Age Groups ◽  
Black Tea ◽  
Extraction Process ◽  
Extraction Methods ◽  
Variable Magnetic Field ◽  
Tea Leaves ◽  
Tea Infusions ◽  
Green And Black Tea

Tea is one of the most popular drinks in the world, commonly consumed by consumers from all age groups mainly due to its refreshing taste, attractive aroma, and potentially beneficial impact on health. The composition of a tea drink depends on numerous factors, such as time and brewing temperature, degree of crumbling of tea leaves, and degree of mixing. Diffusion of the polyphenolic compounds, minerals, caffeine or theanine typical of tea infusions have been the subject of studies conducted by numerous authors. Promoting the extraction of amino acids from tea leaves when preparing infusions through the induction of a magnetic field constitutes not only another step towards the optimisation of the extraction process, but is also one of the methods to improve the nutritional value of tea infusions. The purpose of this work was to verify a hypothesis concerning the improvement of the extraction of amino acids from dried tea during the preparation of infusions by applying a permanent or variable magnetic field induced under laboratory conditions. A variable magnetic field applied as a factor assisting extraction resulted in an increased concentration in the total number of amino acids in green and black tea infusions. A statistically significant improvement in the level of free amino acids was observed after application of extraction assisted by a variable magnetic field with induction at 100 mT and a frequency of 50 Hz. Extraction using a variable magnetic field for tea infusions may constitute a good solution to assist traditional water extraction methods for research purposes.

Comparative Study on the Effect of Sweeteners on the Oxidative Status of Green Tea and Black Tea

2017 ◽  
Vol 68 (6) ◽  
pp. 1406-1412 ◽  
Author(s):  
Petre Savescu
Keyword(s):  
Free Radicals ◽  
Chemical Composition ◽  
Food Additives ◽  
External Environment ◽  
Black Tea ◽  
Antioxidant Effect ◽  
Oxidative Status ◽  
Nutritional Recommendations ◽  
Green And Black Tea ◽  
Selection Of

Both green and black tea are known by the consumers for their chemical composition rich in polyphenols � substances with an important antioxidant effect, proofing the capacity to fight against free radicals and to strengthen the immunity system. In order to improve the sensorial characteristics of green and black tea, the main food additives used are natural and synthetic sweeteners. Knowing how to choose the best sweetener for organic green and black tea is a duty of any specialist in this field, in order to improve the capacity to make nutritional recommendations � taking into consideration the different health level of the consumers (especially the ones with diabetes or cardiovascular symptoms or diseases, digestive or hormonal problems or allergies). The present paper shows a personal method for finding of the best synthetic or natural sweeteners that can be used for sweetening the organic green or black tea coming from areas without any contamination. This method allows the selection of optimal sweetener by monitoring the oxidative status of internal and external environment for green and black tea.

Geographical origin identification of pure Sri Lanka tea infusions with electronic nose, electronic tongue and sensory profile analysis

2010 ◽  
Vol 24 (3-4) ◽  
pp. 121-130 ◽  
Author(s):  
Zoltán Kovács ◽  
István Dalmadi ◽  
Larina Lukács ◽  
László Sipos ◽  
Katalin Szántai-Kőhegyi ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Electronic Nose ◽  
Geographical Origin ◽  
Profile Analysis ◽  
Electronic Tongue ◽  
Sensory Profile ◽  
Tea Infusions ◽  
Origin Identification

scholarly journals The Bifunctional Catalase-Phenol Oxidase of Mycothermus Thermophilum (MtCATPO) Increases the Antioxidant Capacities of its Ortho-Diphenolic Substrates and of Green and Black Tea Extracts

2021 ◽  
Vol 9 (4) ◽  
pp. 689-695
Author(s):  
Betül Söyler ◽  
Zümrüt Begüm Ögel
Keyword(s):  
Oxidase Activity ◽  
Black Tea ◽  
Phenol Oxidase ◽  
Phenol Oxidase Activity ◽  
Antioxidant Capacities ◽  
Tea Infusions ◽  
Wide Range ◽  
Potential Applications ◽  
Tea Production ◽  
Green And Black Tea

Catalase from the thermophilic fungus Mycothermus thermophilus is a bifunctional enzyme with a secondary phenol oxidase activity (CATPO). MtCATPO catalyses the oxidation of catechol, chlorogenic acid, caffeic acid and (+)-catechin to yield mainly dimers, and higher molecular weight oligomers and polymers. The role of this phenol oxidase activity is not known. Here, the antioxidant capacities (AC) of the phenolic substrates in the absence and presence of MtCATPO were compared. The oxidized products displayed enhanced AC reaching a maximum of 2.4-fold with catechol. Other phenol oxidases (laccase and tyrosinase) did not yield AC enhancement to the same extent. MtCATPO-treatment increased AC of green and black tea infusions, as well as water extracts of samples collected from a black tea production line up to 28%. The bifunctional MtCATPO appears to be an important antioxidant enzyme with a wide range of potential applications in the food, neutraceuticals and pharmaceuticals industry.

Sign in / Sign up

Export Citation Format

Share Document