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Various instant teas produced differently from black tea [freeze-dried instant tea (FDIT), spray-dried instant tea (SDIT), and decaffeinated instant tea (DUN, were compared for their differences in volatile compounds as well as descriptive sensory analysis (DSA). A total of 63 volatile compounds in all tea samples (eight aldehydes, ten alcohols, nine ketones, five esters, eight acids, ten terpenes/terpenoids, ten furans/furanones, two pyrroles, and one miscellaneous compound) were tentatively identified. Black tea, FDIT, SDIT, and DCIT contained 60, 55, 47, and 40 volatile compounds, respectively. Ten flavour attributes such as after taste, astringency, bitter, caramel-like, floral/sweet, green/grassy, hay-like, malty, roasty, and seaweed were identified. Intensities for a number of flavour attributes (except for caramel-like in SDIT and bitter and after taste in DCIT) were not significantly different (p > 0.05) among tea samples. The present study suggests that instant teas can also be used as good alternative to black tea. (C) 2015 Elsevier Ltd. All rights reserved.

Two instant tea samples formed as much DBPs as aquatic humic substances under the same reaction conditions, although the concentration of tea used for consumption typically is much higher than the concentration of humic substances in natural waters. At typical tea concentrations, substantial levels of TOX (164−196 μg/L as chloride) were generated when chlorinated at 4 mg/L. The TOX formed exceeded the Swiss limit of 25 μg/L as referenced by Fleischacker and Randtke (1983). Use of boiled water in preparation of instant tea is suggested if the residual free chlorine in the tap water is high. Keywords: Disinfection byproducts; DBPs; chlorination; instant tea; tap water

TEZ10270 Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 2014. Kaynakça (s. 57-72) var. x, 93 s. : tablo ; 29 cm. Bu çalışmada, bazı poşet çaylardan ıhlamur, rezene, adaçayı, mate, ekinezya, papatya, form, siyah ve yeşil çayların fenolik bileşenleri ve antioksidan aktiviteleri belirlenmiştir. Bu çalışmada kuru çaylardan elde edilen ekstraktlar ile bu çayların uygun koşullarda demlenmesiyle oluşan infüzyondan elde edilen ekstraktlardaki toplam fenolik madde miktarı, toplam antioksidan aktiviteleri ve bazı fenolik bileşenlerinin miktarı belirlenmiş deme geçiş oranları irdelenmiştir. Toplam fenolik madde içeriği hem kuru çayda hem de demlenmiş çayda en fazla yeşil çayda ardından siyah çayda bulunmuştur. Demlenmiş çaylarda antioksidan aktivitesi en yüksek olan çaylar ise adaçayı, ıhlamur, ekineyza ve matedir. Hem kuru çayda hem de demlerinde toplam fenolik madde miktarı ile antioksidan aktiviteleri arasında korelasyon bulunmamıştır. Kuru çaylarda bulunan toplam fenolik madde miktarı ile demlerine geçen toplam fenolik madde miktarı arasında da korelasyon bulunmamıştır. Araştırmada fenolik bileşenlerin demlenmiş çaylardaki dağılımına bakıldığında; vanilik asit, kuersetin, şirincik asit en fazla ıhlamur çayında; gallik asit ve epikateşingallat (ECG) rezenede; (-)epikateşin, klorojenik asit, ferulik asit, apijenin, kafeik asit matede; rutin ve ellajik asit form çayında; luteolin ekinezyada; izokuarsetin ve rosmanirik asit adaçayında; komferol, p-kumarik asit ve ± kateşin siyah çayda; epigallokateşingallat ise yeşil çayda en fazla bulunmuştur. Bu fenoliklerden gallik asit, izokuarsetin, vanilik asit, klorojenik asit, apijenin ve luteolinde kuru çaylar ve demlerdeki miktarları arasında anlamlı korelasyonlar bulunmuştur. In this study, phenolic compounds and antioxidant activities of some kind of tea bags including linden,fennel,.sage,mate,echinacea,chamomile,form,.black and green teas were identified. In this study, the extracts obtained from dry tea; total phenolic content in the tea extracts obtained by infusion through brewing under proper conditions; antioxidant activites and transition level of some kind of phenolic compounds in the brewing proccess were identified. The highest level of total phenolic content in dry tea and brewed tea were found in green tea and secondly in black tea. The highest antioxidant activity level among brewed tea was found in linden, echinacea, sage, form and mate. A statistically significiant correlation was not found between the total amount of phenolic compounds and antioxidant activity for both in dry tea and brewed tea. Also the correlation between the amount of total phenolic compunds in dried tea and the amount of total phenolic compounds transited into brewed tea was not statistically significant. In terms of the distribution of phenolic compounds in brewed tea ; the highest level of vanillic acid ,quercetin,syringic acid were found in linden tea; gallic acid and epicatechin gallate(ECG) were found in fennel ;(-) epicatechin, cholorogenic acid, ferrulic acid, apigenin and caffeic acid were found in mate; rutin and ellagic acid were found in form tea; luteolin was found in echinecea; isoquercetin and rosmanirik acid were found in sage;.kamferol, p-cumaric acid and catechins were found in black tea and EGCG was found in green tea. Statistically significiant correlations were found between the quantities of phenolic acid; gallic acid; isoquercetin,vanillic acid ,cholorogenic acid,.luteolin. and apigenin in both dry and brewed tea. Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi tarafından desteklenmiştir. Proje No: ZF2012YL34.

Modifications were made to a bench-top dustiness tester to allow for the simultaneous collection of dust generation and separation force data. Tests were performed on limestone, glass beads, titanium dioxide, and lactose, and their results compared to data from a previous study for a large-scale tester. The results of tests on these and four additional materials (instant tea mix, copier toner, baby powder, fly ash) were then compared to a model by Plinke et al. (1995) for predicting the amount and size distribution of dust generation. All of the test materials except glass beads followed the trends in dust generation of the previous study. The results of these tests were then compared to the proposed model. Titanium dioxide and limestone both followed the model very well with 91% and 86% of the data within one standard error of the model respectively. Glass beads and lactose did not perform as well as the other materials each having 45% of their data within one standard error. Overall, 67% of the...

One self-selected study (study A) and one laboratory-controlled study (study B) were conducted to investigate the effect of tea consumption on zinc bioavailability in healthy humans. The 14-day study A consisted of two 7-day experimental periods, while the 28-day study B consisted of two 14-day experimental periods. In study A eight subjects and in study B ten subjects were participated. Subjects of study A consumed self-selected diets and kept a record of foods eaten. In study B, subjects ate a constant and weighted laboratory controlled diet. In both studies, subjects consumed 8 g of instant tea during tea supplementation periods. Complete urine and fecal collections were made by subjects of both studies. Zinc contents of urine, fecal and food samples were determined by using Atomic Absorption Spectrophotometer. Mean zinc intakes of humans consuming self-selected diets were below the RDA. Mean urinary zinc excretion, fecal zinc excretion and zinc balance were unaffected by the tea consumption. Negative zinc balances in study A and positive zinc balances in study B were observed in both tea and no tea dietary treatments. Tea consumption showed a small but not statistically significant adverse affect on zinc bioavailability in humans.

In order to assess the levels of fluoride ingestion through intake of tea, studies were conducted with four different brands of tea leaves commonly available in the Indian market. Four most prevalent methods for the preparation of tea with various contact times (2,4,6,8 and 10 min) of tea leaves with water show that: (a) leaching of fluoride is least in case of leaf tea as compared to powdered tea (F levels increasing with decreasing grain size); (b) leaching of fluoride reaches a maximum after a contact of about 6 min; (c) there is no difference between levels of fluoride with or without addition of milk in the English style where tea leaves are not boiled, while for the Indian style, addition of milk and subsequent boiling resulted in reduction of fluoride levels and (d) ingestion of fluoride per cup of tea ranged from 1.55 mg/l to 3.21 mg/l amounting to an intake per day per person of fluoride between 0.3 to 1.9 mg.

Trihalomethanes (THMs) are suspected carcinogens and reproductive toxicants commonly found in chlorinated drinking water. This study investigates THM formation during the preparation of beverages and foods using chlorinated drinking water. A total of 11 foods and 17 beverages were tested. Under the experimental conditions, each food and beverage formed THMs, primarily chloroform, although low or trace levels of brominated THMs were also detected. Tea formed the highest THM levels (e.g., chloroform levels from 3 to 67 microg l(-1)), followed by coffee (from 3 to 13 microg l(-1)), rice (9 microg l(-1)), soups (from 0.4 to 3.0 microg l(-1)), vegetables (

At present, the commonly used HPLC method for the analysis of caffeine content in tea brews employs direct application of the samples on the column. This practice gradually reduces the efficiency of the column and shortens its life. In the modified method, the interfering tea pigments are effectively removed by passing the sample through a Sep-Pak C18 cartridge. Then its injection on a reversed phase μ-Bondapak C18 column employing acetonitrile and water (20:80 v/v) as mobile phase reduces the analysis time without affecting either the resolution of the peaks or the accuracy of caffeine determination. This method is shown to estimate accurately soluble caffeine contents in the brews of black tea, decaffeinated tea, and decaffeinated instant tea samples. Thus, the method is ideally suited for rapid routine anaylsis of black tea and its products. Keywords: Caffeine; Sep-Pak C18; decaffeinated tea; HPLC; instant tea

Caffeine extraction procedures from water soluble and water insoluble materials for preparing stimulating beverages are described. Water soluble materials used were instant tea and coffee and water insoluble materials were, among others, guaraná powder and maté leaves. The extraction of caffeine from water soluble materials, especially instant tea, is more suitable for an organic chemistry teaching laboratory than the classic experiment using tea leaves, due to the economy of time and a larger amount of extracted caffeine. The procedure is time-saving and requires only a four-hour period. The experiments illustrate the extraction process as used in undergraduate organic chemistry laboratories.

The extraction of tea solids with water under the influence of ultrasound has been studied with respect to the effects of temperature, irradiation time and power. Sonication improved the extraction at 60 °C by nearly 20%, approaching the efficiency of that of thermal extraction at 100 °C. The extracts were not assessed for taste.

The purpose of this study was to determine the quality of herbal raw materials and consumer acceptability to the instan tea. Celery and aloe vera leaf have an ability to lower blood pressure. The combination of these two herbs are expected to have a synergistic effect in this instant tea. The formulation tea showed the appropriate with the requirements and no difference in taste, color and odor in statistic of the three formulations.Keywords: formulation, celery, aloe vera

The coupling of power-ultrasound with well established but under-exploited electrochemical stripping voltammetry has led to the emergence of a powerful new analytical technique – sonoelectroanalysis. Where classical electroanalytical techniques were plagued with electrode-fouling and/or sensitivity limitations, the introduction of ultrasound into the system has given great increases in analytical efficiency and substrate applicability, predominantly through enhanced mass transport and electrode surface activation. This revitalised analytical technology has been applied to a range of modern analytical problems, allowing sensitive determination of a wide number of analytes from a variety of otherwise hostile matrices, including copper in beer and blood, lead in wine, petrol and river bed sediment, vanadium in aqueous media, nitrite in egg and manganese in instant tea granules. This paper gives an overview of these recent advances.

A 45-year-old white male was found to have radiographic findings of a diffusely dense appendicular skeleton, mild trabecular thickening, and multiple thoracic compression fractures indicating structural weakness. Bone mineral density was above the expected range for his age on the lumbar spine and femoral neck. Social history was significant for well-water consumption and daily instant-tea ingestion …

The effect of tea and coffee, with and without milk, on the solubility of added zinc and calcium after a sequential pH change to 2 and 6 was investigated. The addition of milk did not decrease the solubility of endogenous zinc or calcium in tea but did in coffee. Liquid tea decreased (P

The single, consistent, comic ‘self’ presented on stage is often deployed in other ways. The comedian may make use of her persona in other kinds of enterprise. Victoria Wood and Rita Rudner have made TV commercials. Dawn French fronts a book of knitting patterns, Helen Lederer has published a book, Coping, which parodies the self-help manuals of the seventies and eighties. In each case the comedian herself acts as a sign which we must interpret in the light of her comic persona — but also a sign which carries more than comic meaning. To watch Wood or Rudner endorsing instant tea or coffee may involve laughter at the jokes within the text but it also means that we respond to them as successful women. To buy a book of patterns for colourful clothes for large women with Dawn French on the cover involves seeing French not simply as a popular comic figure but as an attractive, well-dressed woman at ease with her size. The persona, in other words, is a construct more durable than the performer’s set, and I should like now to turn to the way in which it operates when the comedian assumes a role. I am not concerned here with specifically dramatic performance; many women comedians do interpret pre-existing texts, and these sometimes impinge upon their standup persona: for example, when Marti Caine played Fanny Brice in Funny Girl at the Crucible theatre in Sheffield she was marketed as a specifically local girl made good and a familiar comic personality.

When a 52-year-old Missouri woman approached physicians in 1998 complaining of stiffness and pain in her spine, the symptoms were at first attributed to “disc disease.” But a series of laboratory tests showed that the woman had abnormally thick, dense bones and strikingly high levels of fluoride in her urine—hallmarks of skeletal fluorosis, a disease that has been diagnosed only a handful of times in the United States. The only way to develop skeletal fluorosis is to ingest or inhale too much fluoride. The woman’s drinking water had only about 2.8 parts per million (ppm) fluoride, well below the Environmental Protection Agency (EPA) limit of 4.0 ppm. Other sources of fluoride were also eliminated: She didn’t swallow her toothpaste, she didn’t work with pesticides, and she didn’t live near a mine. So where was she getting all the fluoride? Then the woman revealed she had drunk up to two gallons of extra-strength instant tea every day of her adult life. Physician Michael Whyte of Washington University School of Medicine and his colleagues decided to measure the fluoride levels in her tea preparation. They found that, counting the fluoride in her water, the woman was ingesting 37–74 milligrams of fluoride per day. EPA studies suggest that severe skeletal fluorosis could occur over the course of 20 years from a continuous exposure of 20 milligrams of fluoride per day. Whyte and colleagues then tested 10 instant teas available in grocery stores. They found average fluoride concentrations of 1.0–6.5 ppm in regular-strength tea made with fluoride-free water, with several brands exceeding the Food and Drug Administration limit of 1.4–2.4 ppm for bottled beverages. Their study appears in the January 2005 issue of The American Journal of Medicine. Whyte believes that individuals who drink large volumes of instant tea for a prolonged period may be putting themselves at risk for skeletal fluorosis. But Joe Simrany, president of The Tea Association of the USA, believes that the Missouri incident was highly unusual. “It had less to do with tea than it had to do with excessive behavior,” he says. So should the average tea drinker be concerned? “It may be that certain brands ought to cut down the amount of fluoride in their tea or add a warning label to their product,” says Michael Kleerekoper, director of research for bone and mineral metabolism at Wayne State University, “but it would be a real mistake to throw out the baby with the bathwater.” He adds, “I drink tea—it’s wonderful on a hot summer’s afternoon.” Whyte, who also hasn’t stopped drinking tea, says, “Our research is a call for better understanding of fluoride levels in various teas.” He is now investigating the fluoride levels of bottled tea preparations. Meanwhile, the woman in Missouri has stopped drinking tea, and her pains have abated. She has since switched to lemonade.

The enzymic browing of extracts from cocoa, coffee and tea was examined using the polyphenol oxidase from Alternaria tenuis strain A-2 and applications of the enzyme were developed. Fermented cocoa was more easily oxidized than unfermented or roasted ones. All cocoa extracts became deeper brown as a result of the enzymic oxidation. Raw cocoa beans which corresponded to fermented cocoa beans were prepared by treating unfermented ones with the enzyme. Coffee extracts were also oxidized by the enzyme. Green coffee turned brown, and roasted one became deeper brown on account of the enzymic oxidation. Darker colored coffee beverage was prepared by the enzymic treatment of instant coffee. Green tea was readily oxidized by the enzyme and turned brown. Instant tea was prepared by converting green tea to black tea using the polyphenol oxidase.

The optical properties of soluble tea and coffee were studied using thin-layer transreflectometry with samples backed by white and black reflecting surfaces. The red, green, and blue transreflectance readings and the calculated internal transmittances, and scattering and absorption coefficients provided information relating to the effect of electrolytes on brew color, to changes in light transmittance and scatter on incremental addition of nondairy creamer to samples dissolved in distilled water and in mineralized water, and to the separate effects of pH and dissolved electrolytes on colorimetric and visual characteristics of the brews. The application of Kubelka-Munk analysis provided physical explanations for visually perceived attributes and reinforced the proposition that with judicious application, even from‘abridged’ data, such an analysis can be a valid and powerful tool.

The c o m p k d , n-triacontanol, reported to have exceptional plant gro wth promoting properties, has now been identified as a constituent of tea. Tea wastes from instant tea processing, green tea and black tea have decreasing quantities of this compound in that order. This may be attributed to the higher firing temperatures in the case of green tea and black tea. Polyphenol oxidase does not seem to have any effect as shown by in vitro experiments.

A new spectrophotometric micro-method for the determination of caffeine in tea is described. This method is then used to evaluate the caffeine content of a variety of brands and blends of bagged and loose hot tea prepared in different strengths and by different brewing methods. In addition, the caffeine content of instant tea, ice tea, and Mr. Coffee automatic tea is evaluated.

This review surveys tea-production technology, chemistry of raw and manufactured tea as well as tea tasting appraisal and chemical analysis of manufactured tea. The paper describes the healthful properties of tea, gives general information on the tea plant and manufactured tea, and presents classification of teas as related to the processing of black green, yellow, and red tea, green pressed tea as well as instant tea and tea dyes. The paper discusses the chemical composition of raw and manufactured tea as well as approaches to the evaluation of tea quality--tea tasting appraisal and chemical analysis. The paper is supplied with the conclusions and references. The section on the healthful properties of tea discusses various aspects of catechin effects--vitamin P, antimicrobial, antioxidative and radioprotective effects. Also described are favorable effects of tea alkaloids--caffeine, theobromine, theophylline that dilatate cerebral vessels and alleviate headaches. The section on the production of different teas (black, green, yellow, red, instant teas, and tea dyes) considers technological methods and biochemical bases of various types of tea manufacture. The role of tea leaf enzymes in the oxidative processes determining the tea quality is discussed in detail. This section also describes the contribution of thermochemical processes into the formation of tea flavor. The compounds dictating tea taste and aroma are discussed, particularly tannins and catechins, volatile oils, nitrogen compounds, and some other substances.

Spent tea leaf (STL), a residue from the manufacture of instant tea, has 30% crude protein and contains significant quantities of essential amino acids. Because of its high polyphenol content it may not be suitable for pigs and poultry, but in view of the more tolerant nature of microflora to tannins it could be a potential source of protein for ruminants. Three trials were conducted with cattle or sheep to evaluate STL as a ruminant feed. In Trial I, three concentrate rations prepared with 0, 10 or 20% STL were found to be readily acceptable by bull calves 6–8 months of age, without any harmful effects upon their health. In Trial II, four concentrate rations having 0, 10, 14 or 18% STL were found to be equally digestible by sheep. In Trial III, groups of 7 male Jersey calves, 5 months old, were given 0, 10 or 18% STL in concentrate rations, and rate of growth and concentrate conversion efficiency were investigated. There was no significant difference between the groups in live-weight gain, which suggests that up to 18% STL may be used in concentrate rations without apparent health problems. The average daily gains for the 3 rations were 288, 274 and 271 g, respectively. On the basis of cost/kg live-weight gain, a ration containing 18% STL would be 25% cheaper than a standard concentrate ration.

An ultraviolet spectropholometric and GLC method for determining caffeine in instant tea utilizes the extraction and cleanup procedures of the official AOAC chromatographic methods for caffeine in APC and in coffee and a KCl thermionic detector. The detector is sensitive to as little as 1 ng caffeine. The method was studied collaboratively in eight laboratories on three instant tea samples. Results were in reasonable agreement, and the method is recommended for adoption as official first action.

To produce an instant tea, the following three processes were preliminarily studied.1. Extracting processFor applying a freezing concentration method in the second process, some concentrated extract had to be obtained in the first step.After trying several extracting methods, an extract having desirable concentration (10°Brix) could be obtained by modifying a batch countercurrent multiple contact method.2. Concentrating processTo decide the optimum density of the extract for freezing concentration, the original extract (10°Brix) and diluted extracts (5-7°Brix) were freezed in an icecream freezer and eliminated the ice crystal by centrifugation. The extract having over 8°Brix concentration was succeeded to be condensed by freezing and after two or three succesive treatments the starting extract (10°Brix) could be condensed up to 30-45°Brix.3. Drying processThe concentrated extract (30-45°Brix) was spread as even as possible 2mm. layer on stainless steel pans and heated at 80°C. under reduced pressure of 10-15mm. Hg.After 2.5-hours heating and then 0.5-hours cooling, well puffed dry powder was obtained. This product was very easily soluble in water and had good taste but less flavor.

For the production of instant tea, the vacuum drying procedure of tea extract was investigated on a laboratory scale.The suitable drying procedure was as follows.The incoporation of air finely dispersed into the. cold tea extract prior to vacuum drying caused the extract to expand, and the tea solids could then be dried as a product with a puffed style.The aerated extact was whighed into stainlesssteel pans at a rate of 10g. per 100 cm2.The loaded trays were then placed in the vacuum dryer, the pressure was reduced to about 1 mm. Hg, and the temperature of the shelves was raised from 50°C. to 70°C. as rapidly as possible. The incoporated air expanded the extract 20- to 40-folds of its initial volume during the early stage of drying.The product temperature had to be maintained under 50°C. to keep its quality good. The drying time required about an hour.This product was very easily soluble in hot water and had good taste but less flavor.

Popular brands of instant and ground coffee, instant and bag tea, and instant hot cocoa mixes were prepared according to manufacturer's directions and analyzed for caffeine and/or theobromine content. After extraction into boiling water, the methylxanthines were separated by high performance liquid chromatography using a reverse phase C18 column and a mobile phase of acetonitrile and water (8:92, v/v). Caffeine content ranged from 32.4–35.0 mg/cup in instant tea, 30.2–67.4 mg/cup in bag tea, 1.0–7.8 mg/cup in instant hot cocoa mixes, 46.7–67.6 mg/cup in instant coffee, and 93.0–163.5 mg/cup in ground coffee. Theobromine concentrations ranged from 1.4–2.3 mg/cup in instant tea, 1.2–4.4 mg/cup in bag tea, and 39.5–79.5 mg/cup in instant hot cocoa mixes.

With the purpose of finding lower cost process, simple preparing processes of the raw material for instant green tea were investigated.The raw materials were made by the following three procedures.1. Usual method : Six processes, i. e., steaming, primary heating and rolling, rolling, secondary drying, final rolling, and drying were employid.2. Simplified method I : Three processes, i.e., rolling, secondary drying, final rolling were eliminated from the usual method.3. Simplified method II : Two processes, i.e., secondary drying, final rolling were eliminated from the usual method.The raw materials made by these three procedures were compared with each other in qualities, constituents, extracted amount of soluble matter, and the instant teas made from these raw materials were also tasted.In this test, no difference was found among these products.So, it was concluded that these simple procedures were suitable for making raw material of instant tea.

Nicotine at several ppm was detected in the dehydrated fresh produce of the Solanaceae species including tomato, potato peel, eggplant and green pepper. Its identity was verified by GLC, TLC and CC-mass spectrometry. The presence of nicotine in all parts of the tomato plant suggested biosynthetic origin. In contrast, the 2 to 23 ppm nicotine found in green tea and instant tea samples might be attributed to insecticide contamination. There was no detectable level of nicotine in non-Solanaceae fruit and vegetables and other processed foods analyzed