Current World Environment

Introduction

Tea refers to the Agri-produce of the leaves, its buds, and internodes of the Camellia sinensis plant, prepared and cured by various procedures. Tea also refers to the aromatic hot beverage prepared from the processed or cured leaves by combination with hot or boiling water, and is the common name for the Camellia sinensis plant itself. The four types of tea most commonly found in the market viz., white tea, black tea, long tea and green tea, and all the tea can be prepared from the same bushes, by using different process. Instant coffee is a beverage derived from brewed coffee beans. Through various manufacturing processes the coffee is dehydrated into the form of powder or granules. These can be rehydrated with hot water to provide a drink similar to conventional coffee with a little test difference. At least one brand of instant coffee is also available in concentrated liquid form1-4. Root chicory (Cichorium intybus var. sativum) has been in cultivation in Europe as a coffee substitute for this, the roots are baked, ground, and used as a coffee substitute and additive, especially in the Mediterranean region, where the plant is native, although its use as a coffee additive is also very popular in India, parts of Southeast Asia and the American South. Copper salts are commonly used as protectant and eradicant in tea, coffee and their instant preparations against blister blight- a fungus disorder that affects the tea and instant coffee. The main risks of the exposure of this salt and bio accumulation of the copper in human beings are gastrointestinal irritation, liver and kidney damage, intravascular haemolysis and shock. Acute poisoning occurs from ingestion of copper salts. The main target organs are the gastrointestinal tract, cardiovascular and circulatory system. Keeping in view of the above  points and the facts that, after water followed by tea than instant coffee is the most widely-consumed beverage in the world as it has a cooling, slightly bitter, astringent flavor and the people is very fond of this specific test. Therefore the present problem has been sorted out to explore the possibility of accumulation of copper in the tea and instant coffee and accordingly an accurate method for the determination of this element which is required for quality control has been developed and its estimation by advanced instrumentation method done during the study period.

Material and Methods

Present study was carried out to explore the possibility of higher content of copper which are being used as eradicant and protectant against a fungus and accordingly the samples of different brand of Tea and Instant Coffee were collected and then method development of detection of different parameters related to purity of the hot beverages was carried out by performing different tests of adulterants in Tea and Instant Coffee. To develop accurate method of sample preparation for copper element and the quality control was the main objective of the present study which is done as per the standard condition, calibration and other sensitivity check of the major sophisticated instrument Atomic Absorption Spectrophotometric (4141), ECIL, Hyderabad for the determination of copper in selected hot beverages.

Results and Discussion

In accordance with the objectives detection of adulterants was carried out in the target commodity as: when tea leaves sprinkled on wet filter paper and it was found that there was no added colour found on the filter paper which shows the absence of adulterants in different brand of tea. Similarly in the test -2 performed during the study period by sprinkling a little tea dust on the lime glass plate red orange colour was not appeared which show the absence of coal tar dye in the present selected samples. The detection tests were performed for the Instant Coffee infusion after adding the  HCl then boiled for some time and after the addition of potassium Ferro cyanide followed by  boiling the contents until the liquid become dark green then added KOH and again boiled the whole contents. It was observed the Liquid become brown which shows the presence of chicory in the instant preparation of different brand of coffee samples obtained for the tests. Similarly other test for the presence of adulterants were carried out by taking different brand of Coffee infusion and then added copper acetate in the infusion reddish brown precipitate was obtained which confirms the presence of Chicory in the samples. Presence was observed in all the three samples of branded coffee powder. Confirmation was also done when the samples thrown on cold water Chicory sinks quickly coloring the water showed positive presence of Chicory. All the observation related to adulteration tests have been shown in the Table-1. Physico- chemical analysis was done to assure the quality of different brand of tea and coffee and it was found that the moisture content was found to be higher (8.7 %) in the sample of coffee (Rich Bru), and the lowest was Nescafe Classic (2.3%). However, it is a fact that coffee has higher moisture % as compared to tea. Similarly, the total ash, the higher and lower percentage was 11.37% and 5.3%, acid insoluble ash (5.0% and 2.6%, water insoluble ash, 8.19% and 5.55% alkalinity 0.008% and, 0.01% was found for all the samples respectively (Fig.-1-5).

Determination of copper in all the samples of tea and coffee was estimated to fulfill the objectives taken during the study period for this method development was done as per the standard condition for operating Atomic Absorption Spectrophotometer and accordingly sample preparations were made in various steps. Copper concentration in different tea samples was found higher with a value of 1.832 ppm (Milli) followed by 0.998ppm (Goodrich), 0.910ppm, (Tata Agni), 0.895ppm (Double Diamond) and 0.781(Taj Mahal Tea Bags) in all the four brands of the tea whereas, in the coffee samples the copper value was found as 0.749 ppm (Nescafe Sunrise) followed by 0.680ppm (Rich Bru) then 0.601ppm (Nescafe Classic) as shown in Fig- 6. The copper concentrations in all the selected samples was found higher and may be due to the copper salt which is being commonly used as protectant and eradicant in tea and coffee and their instant preparations against blister blight- a fungus disorder that affect the teas and coffee plants. The data shows that there is absorption or uptake of the copper sulphate by the plants during the cultivation which can be emphasized that hot beverage is quite unsafe as the bioaccumulation of the copper bioconcentration is in higher side which are commonly practiced as protectant and eradicant for the specific fungus.

Physico-Chemical Characteristics and Copper Concentration in Hot Beverages Click here to View

Acknowledgements

Thanks are due to Prof. Pramod K. Verma, Director General and D. K. Soni, Sr. Scientist and In charge Quality Assurance Laboratory, Madhya Pradesh Council of Science and Technology for extending support and constant encouragement. The authors are also thankful to all the staff of QAL offered selfless support and assistance to perform experimental work.

References
 

1.    Romualdo Verzosa Jr. Ed (1993). Encyclopedia of Chemical Technology, volume 6 (4 th edition). John Willey and Sons ISBN 0-471-52674-6.
2.    Masters, K (1991). Spray Drying Handbook (5th Edition). Longman Scientific & Technical. ISBN 0-582-06266-7
3.    John J. McKetta, Ed (1995). Encyclopedia of Chemical Processing and Design. Marcel Dekker Inc. ISBN 0-08247-26046-9
4.    Carlisle, Rodney (2004). Scientific American Inventions and Discoveries, p.355. John Wiley and Songs, Inc., New Jersey. ISBN 0-0471244-104