Tea, Coffee, And Cocoa Preparations | by Guilford Lawson Spencer
Adulteration of coffee, tea, and chocolate
| Title | Tea, Coffee, And Cocoa Preparations |
| Author | Guilford Lawson Spencer |
| Publisher | Authority of The Secretary Of Agriculture, Washington |
| Year | 1892 |
| Copyright | 1892, Authority of The Secretary Of Agriculture, Washington |
| Amazon | Tea, coffee, and cocoa preparations |
By Guilford L. Spencer, Assistant Chemist, With The Collaboration Of Mr. Ervin E. Ewell
Letter Of Transmittal- It. S. Department of Agriculture, Division of Chemistry, Washington, D. C., March 1, 1892. Sir: I beg to transmit herewith for your inspection and approval the manuscript of Part Seventh of Bull...
- Tea
- Tea is prepared from the various species of Thea. This plant is a hardy evergreen shrub. Statistics Of Tea Consumption The extent of the consumption of teas is shown by the following Statements ...
- Black Teas
- 1 The methods of the manufacture of black teas in Japan is essentially as follows: The leaves are withered by exposure to the sun, fire being used only in cloudy or rainy weather. An hour's sunning...
- Green Tea
- The leaves are first steamed until they lose their elasticity. The operations of rolling and drying follow the steaming. The leaves are finally sorted by means of a series of sieves. In China, instead...
- Adulteration - Definition
- The law of the State of New York (see Part 2, Bulletin 13, p. 239) defines adulteration of food as follows: The term food, as used in this act, shall include every article used for food or drink ...
- Adulteration - Methods
- Facing. - The treatment of teas with various coloring matters, a process termed facing, comes properly under the head of adulterants. Facing consists in treating the prepared leaves with mixtures cont...
- Detection Of Facing
- Facing is usually easily detected by the microscope. A portion of the leaf is mounted as an opaque object, the coloring matter appearing in small dots. Prussian blue. - This substance is easily det...
- Spent Or Exhausted Leaves
- The detection of spent or partially exhausted leaves in teas is not a simple problem. The chemical methods all depend upon the proportion of certain of the soluble constituents which remains in the te...
- Foreign Leaves
- The addition of foreign leaves is best detected by means of the microscope. The leaf of the tea plant is quite characteristic in its venation, serration, and stomata. The veins recurve before reaching...
- Foreign Astringents
- Catechu. - Teas are sometimes treated with this substance to increase their astringency and indicate a greater strength than they naturally possess.1 Hager's method for the detection of catechu gave v...
- Added Mineral Matter
- Soapstone, gypsum, etc. - These substances, as has been stated, are detected by the ordinary methods of qualitative analysis, the particles to be examined being separated from the leaves by shaking in...
- Lie Tea
- This substance, as its name implies, is an imitation of tea, usually containing fragments or dust of the genuine leaves, foreign leaves, and mineral matters, held together by means of a starch solutio...
- General Remarks On Tea Adulterants
- The adulterants of teas, as a rule, are not such as may considered prejudicial to the health. The mineral matters employed in facing, etc., with the exception of salts of iron or copper, are insoluble...
- General Statements Concerning The Constituents of Teas
- The analyses of teas give little or no evidence bearing upon the market value of this commodity. A tea may be very rich in theine or tannin, and yet bring the same price as one poor in these substance...
- Analytical Methods
- In the following paragraphs are presented the methods adopted for the estimation of the various constituents of teas. Caffeine or theine, C8H10N4O2. - After experiments with a number of methods for...
- Report Of The Examination Of Samples Of Teas Bought In The Open Market
- The samples examined in the course of the investigations were purchased in stores of all grades. The analyses of these teas and general statements concerning them are given in the following tables: ...
- Coffee
- The seeds of the Coffea arabica, after roasting at a temperature approximating 200C, are ground and employed in preparing the popular beverage termed coffee. Various substitutes have been prepare...
- Statistics Of Coffee Consumption
- The following statistical statements are based on the Report of the United States Treasury Department:1 Imports of coffees, less the amount exported. Pounds. ...
- General Statements on Coffee
- Of the following statements those in quotation marks are from the observations of Lascelles:1 West India coffee is for the most part even-sized, pale, and yellowish, firm and heavy, with fine arom...
- Coffee Chemical Composition
- In preparing the tables on the following pages, showing the composition of Coffees, the better known authorities have been consulted and analyses have been selected which give the principal constituen...
- Coffee Chemical Composition. Part 2
- The caffetannic acid of coffee has been isolated by Pfaff8 and by Rochleder.9 The latter chemist also reported the presence of traces of citric acid. Caffetannic acid as isolated by W. H. Krug in conn...
- Methods Of Coffee Analysis
- In the detection of adulterants but little chemical work is necessary, hence methods will only be given tor the estimation of the principal constituents of coffee. Moisture. - Dry in a flat dish to...
- Coffee Adulteration - Definition
- Referring to the law of the State of New York (p. 870), the adulteration of coffees may be defined as follows: The addition of foreign matter of any kind to reduce the strength or affect the quality; ...
- Coffee Adulterants And Their Detection
- Facing or coloring. - It is not an uncommon practice to treat inferior or damaged coffees by some process for the improvement of their appearance and in imitation of superior grades. Java seems to hav...
- Coffee Adulterants And Their Detection. Part 2
- 1 Ding. Polyt. Journ., 211, 78; Jahresb. d. Chem.. 1874, 1043. 2 Ding. Polyt, Journ., 215,84; Am. Chemist, 6, 220. 3 Arch. Pharm. [3], 8,298; Jahresh. .1. Chem., 1876, 1021. 4 Moniteur Scient...
- Coffee Adulterants And Their Detection. Part 3
- Mogdad coffee. - This adulterant or substitute consists of the seeds of the Cassia occidentalis.1 E. Geissler2 examinedMogdad coffee by Hager's method and found that it sinks very rapidly in water and...
- Substitutes For Coffee
- A number of substitutes for coffee have been proposed. Many of these have little claim to be entitled substitutes, since they simply furnish a decoction more or less bitter and of a coffee color. S...
- Imitation Coffees
- Within two or three years the coffee markets have been flooded with imitation coffees. The first official action toward suppressing this fraud in this country was probably that of the New Jersey offic...
- Imitation Coffees. Part 2
- Dr. Van Hamel Roos calls attention to the following novel scheme for the sophistication of coffee berries:2 The microscopical examination of a sample, rendered suspicious by its dark color, showed ...
- Report Of Examination Of Coffee Samples Bought In The Open Market
- The samples included in the following report were purchased in stores ranging from the best class to the poorest. The grades of coffee fairly represent the market: Description Of Samples Examined ...
- Roasted Coffees
- But three of the samples of whole roasted coffees were adulterated. Knowing the large amount of imitation coffee that is on the markets this result was unexpected. The adulterated samples were Nos. 68...
- Ground Coffees
- Ground coffees afford a very wide field for adulterations. This class of coffees is sold largely by the smaller dealers. The large stores Usually grind the coffee to order, but in the latter case the ...
- Coffee Extracts
- Three samples of coffee extracts were examined, viz: Serial Nos. 6875, 6895 and 6897. No. 6875 contained no caffeine. On further examination it was found to contain cereals or other starchy bodies and...
- Tin Poisoning - By Preserves In Tin Cans
- It seems to me that sufficient attention has not been paid to the impurities of preserves and to poisoning by compounds of tin. It is only during recent years that chemists and hygienists have given t...
- Coffee Substitutes
- The number of coffee substitutes on the market is large. Many of these are sold under this name and others are simply designated as substitutes. Sample No. 8852 was sold as a coffee substitute. It is ...
- Cocoa Preparations. The Nature, Source, Commercial Importance, Etc., Of The Cocoa Bean
- By Ervin E. Ewell. The raw material from which the cocoas and chocolates of commerce are manufactured is the cocoa bean, the seed of the cocoa, or cacao, tree (Theobroma cacao). While this tree h...
- Cocoa Chemical Constituents
- On account of the peculiar properties of the cocoa bean, its preparations merit a place on our tables for two reasons: In addition to being like tea and coffee, the material for the preparation of a p...
- Cocoa Chemical Constituents. Part 2
- Physical and chemical constants for the fat of the cocoa bean. Analyst. Character of samples. Physical constants for the fat. Chemical constants for the...
- Cocoa Chemical Constituents. Part 3
- Bell1 reports 2.20 per cent of cocoa red in raw beans; Muter, 3.96 per cent. Gum. - It is precipitated from the aqueous solution of the fat-free beans by alcohol. After drying it resembles gum arab...
- The Commercial Preparations Of The Cocoa Bean, Their Nature, Methods Of Preparation, And Adulteration
- The preparations of cocoa are so numerous that more or less confusion of terms naturally arises. Most American manufacturers prepare a plain chocolate (known in Europe as cacao-masse), made by reducin...
- Cocoa Bean Commercial Preparations, Their Nature, Methods Of Preparation, And Adulteration. Continued
- Konig and Wesener1 report a cocoa sweetened with saccharine, of which it contained 0.40 per cent. Another analysis is reported showing 0.76 per cent of saccharine (Chem. Ztg., 1888,106; also Konig).1 ...
- Cocoa Microscopical Examination
- For a thorough study of cocoa preparations, a microscopical examination is indispensable. An accurate knowledge of the structure of the cocoa bean and of the substances used as adulterants is necessar...
- Cocoa Microscopical Examination. Continued
- The starch grains are spherical, or nearly so, have a very indistinct nucleus, react only feebly with polarized light, rapidly lose the blue coloration imparted by iodine, and show only a slight tende...
- Methods Of Cocoa Analysis Reported By Various Chemists
- A brief review of the methods that have been used or recommended for the analysis of cocoa and its preparation is here given. If any important recently reported methods have been omitted, it is due to...
- Methods Of Cocoa Analysis Reported By Various Chemists. Part 2
- Dieterich.6 - Equal parts of the fat and paraffin are melted together, a drop of the mixture placed on a slide and covered with a cover glass. After twelve hours this is examined with a power of 20 di...
- Methods Of Cocoa Analysis Reported By Various Chemists. Part 3
- Mulder.7 - Ten grams of cocoa are rubbed to a paste with water and boiled for fifteen minutes; some MgO is now added and the mixture evaporated to dryness on the water bath with continual stirring. Th...
- Methods Of Cocoa Analysis Reported By Various Chemists. Part 4
- Determination of commercial glucose in chocolates. - In regard to the determination of the sugars used for sweetening chocolates, M. Schrcederrites as follows: The detection and estimation of less...
- Methods Of Cocoa Analysis Reported By Various Chemists. Part 5
- 6Further Gewerbe Ztg., 1868, 63; Zeit. f. anal. Chem., 8, 514. 7 Op. cit., note 3, p. 949 of this work. Determination of water-insoluble organic matter. - Bensemann.1 - Two grams of the substance a...
- Methods Of Cocoa Analysis Reported By Various Chemists. Part 6
- For a more exact determination of the sugar, a gravimetric determination of the reducing sugars in the aqueous extract, before and after inversion, is recommended. (Weight of copper obtained after inv...
- Summary Of Results Obtained By Various Analysts
- A summary of the results of analyses by various chemists is presented in the tables given below. These analyses were obtained, for the most part, from Konig's Chemie der menschlichen Nahrungs- und Gen...
- Summary Of Results Obtained By Various Analysts. Continued
- Number. Analyst. Description of sample. Date. No. of analyses. Water. Nitrogenous substances (total nitrogen X 6.25). ...
- Results Of The Examination Of Cocoa Preparations In The Laboratory of The U. S. Department Of Agriculture
- As cocoa preparations are always sold in the original packages of the manufacturer, the purchase of samples does not need to be conducted with the care and precautions that are necessary in the case o...
- Results Of The Examination Of Cocoa Preparations. Continued
- Summary of the results of analyses made in the laboratory of the U. S. Department of Agriculture. Number of samples examined. Character of samples. Number of sampl...
- Discussion Of The Results Obtained
- While the time at our disposal has not permitted as thorough an investigation in some details of the work as seemed desirable, sufficient data have been obtained to show the general character and exte...
- Bibliography Of The Literature Of Tea, Coffee, And Cocoa Preparations. General Works
- Battershall. Adulteration of food. 1887. Bell. Analysis and adulteration of food. Blyth. Foods: Their composition and analysis. London, 1882. Chevaluer. Dictionnaire. des alterations et falsi...
- Bibliography Of The Literature Of Teas
- Allen, A. H. Tea, adulterations of. Chem. News, 29, 167, 189, 221; 30, 2. Anonymous. - Batalin, a substitute for tea. Chem. Centrbl., 1, 52. Anonymous. Tea, Brick. Chem. Ztg., 1889, No. 11; Zeitscb. f...
- Bibliography Of The Literature Of Coffees
- Allen, A. H. Coffee, examination of. Chem. News, 29,129,140,167. Anonymous. Coffee, acorn. Pharm. Jour., 1876, 772. Coffee, colored. Jour, de Pharm. et de Chim., 15 Feb., 1888, 198. Coffee, extract...
- Bibliography Of The Literature Of Coffees. Continued
- Wittstein, G. C. Coffee, polishing of; Chem. News, 33,194. Wolffenstein. Coffee substitutes, analysis of. Zeitsch. f. angew. Chem., 90, 84; Chem. Centrbl., 1890,606. Cocoa And Cocoa Preparations...
- Bibliography Of Methods For The Estimation Of Tannin
- Allen, A. H. Nearly all the methods worthy of detailed description are based on the precipitation of tannin by gelatin or its absorption by a gelatinous substance. Many of the methods appear very simp...
- Bibliography Of Methods For The Estimation Of Tannin. Part 2
- Gerland. A method based upon the precipitation of tannin by tartrate of antimony and potassium, in the presence of ammonium chloride. Chem. News, 1863, 54; Zeitsch. f. anal. Chem., 2, 419. Gintl, W...
- Bibliography Of Methods For The Estimation Of Tannin. Part 3
- Maumene. A method for the estimation of tannin in wines. The tannin is precipitated by barium hydrate, and the precipitate after washing is dissolved in dilute sulphuric acid and titrated with permang...
- Additional References To The Literature Of Tannins
- Buchner. Tannin estimations, criticisms on. Jsb. d. Chem., 18, 862 (1867); Dingl. polyt. Jour., 184, 250, 330. Carles, P. Tannin, gelatin solution for estimating. Chem. News, 51, 297; Zeitsch f anal. ...
- Additional References To The Literature Of Tannins. Part 2
- Commaille, A. Five grams of the powdered tea are mixed with 1 gram of calcined magnesia, dried twenty-four hours, and the caffeine extracted with three successive portions of chloroform. The chlorofor...
- Additional References To The Literature Of Tannins. Part 3
- Snyder, Harry. Author states that the albuminoids of tea are almost entirely insoluble in hot water. He extracts the powdered sample with four or five portions of hot water, collects the residue on a ...
- United States Tea Adulteration Law
- Be it enaoted by the Senate and House of Representatives of the United States of America in Congress assembled, That from and after the passage of this act it shall he unlawful for any person or perso...
- Abstracts From The Italian Law (August, 1890) Relating To The Adulteration Of Foods
- [Translated from Revue Internationale de Falsifications, 15 Juin, 1891.] XXI. - Coffee. Art. 155. It is forbidden to apply the name coffee, or to sell under this name any substance, whether in...
- List Of Leaves Illustrated By Plates XXXIX And XL
- 1. Tea. 2. Mate, or Paraguay tea (Ilex Paraguayaensis). 3. Camellia (Camellia Japonica). 4. Hawthorn. 5. Box Elder. 6. Horse Chestnut. 7. Sycamore. 8. Rose. 9. Plum. 10. Elm...
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