Roasting types

The principal direct raw materials used to make sulfuric acid are elemental sulfur, spent (contaminated and diluted) sulfuric acid, and hydrogen sulfide. Elemental sulfur is by far the most widely used. In the past, iron pyrites or related compounds were often used but as of the mid-1990s this type of raw material is not common except in southern Africa, China, Ka2akhstan, Spain, Russia, and Ukraine (96). A large amount of sulfuric acid is also produced as a by-product of nonferrous metal smelting, ie, roasting sulfide ores of copper, lead, molybdenum, nickel, 2inc, or others. 

Blending. Most chocolate and cocoa products consist of blends of beans chosen for flavor and color characteristics. Cocoa beans may be blended before or after roasting, or nibs may be blended before grinding. In some cases finished Hquors are blended. Common, or basic beans, are usually African or BraziUan and constitute the bulk of most blends. More expensive flavor beans from Venezuela, Trinidad, Ecuador, etc are added to impart specific characteristics. The blend is deterrnined by the end use or type of product desired. 

Ni is found in many ores in combination with S, As Sb, the chief sources being the minerals chalcopyrite, pyrrhotite and pentlandite. Ni ores are of two types, sulfide and oxide, the former accounting for two-thirds of the world s consumption. Sulfide ores are refined by flotation and roasting to sintered Ni oxide, and either sold as such or reduced to metal, which is cast into anodes and refined electrolytically or by the carbonyl (Mond) process. Oxide ores are treated by hydrometallurgjcal refining, eg, leaching with ammonia. Much secondary Ni is recovered from scrap (Refs 6 7) 1... 

Raw ingredients and cooked recipes were analyzed for stable isotopes of carbon (Abonyi 1993). To our knowledge, no one has determined if there are differences in the stable isotope values of raw and cooked foods, however Hastorf and DeNiro (1985) did compare plant remains that were heated to those that had not been heated. They found no significant difference in isotope values due to heating. Marino and DeNiro (1987) studied the effects ofheating (boiling and roasting) on several types of plants to determine if cellulose... 

The roasting process mostly applied to sulfidic sources is carried out in appliances of different types with different design features. Without describing their features and constructional details, it may simply be mentioned here that some of the widely acclaimed roasting units are traveling grate furnaces, multiple hearth furnace, rotary kilns, and fluid-ized-bed roasters. 

Cepeda, A., Paseiro, P., Simal, J., and Rodriguez, J.L., Determination of caffeine by UV spectrometry in various types of coffee green coffee and natural roasted... 

Decaffeination of green coffee beans is most usually carried out with a water/solvent partition system. The green coffee beans are first steamed until they are hot, wet, and swollen, to make the caffeine available. Solvent is then used to extract the caffeine out of the aqueous phase of the beans. Finally, the beans are steamed to drive off residual solvent. The coffee beans lose their wax surface covering in the process, as well as some flavor components. For this reason, the Robusta and Brazilian Arabica coffees that are dry-processed and have the most powerful flavors are usually the types that are decaffeinated. They become milder in the process. Mechanical polishing is used to improve the appearance of decaffeinated green coffee beans if they are not to be roasted immediately. Extra care is required, however, to store these decaffeinated beans since the loss of wax covering as well as caffeine renders them much more susceptible to fungal attack. 

One of the most significant differences between Arabica and Robusta coffees is in the caffeine content. Robusta coffees contain almost twice the caffeine found in Arabica coffees. There are some other differences recognized thus far Robustas contain almost no sucrose and only very small amounts of the kaurane and furokaurane-type diterpenes they contain higher proportions of phenols, complex carbohydrates (both soluble and hydrolyzable), volatile fatty acids on roasting, and sulfur compounds, all in comparison with Arabicas. References to these distinctions can be found in Chapter 6 of this book. 

Several alicyclic compounds identifiable in roasted coffee are terpenes and these contribute presumably to the coffee oil. The kaurane and furokaurane type diterpenes are discussed in Section VIII.D. 

Caffeine consumption is primarily due to coffee, tea and soft drinks. In the U.S., it is estimated that coffee contributes to 75% of the total caffeine intake, tea is 15%, and soda with caffeine accounts for 10% 5 chocolate and other caffeine-containing foods and medications contribute relatively little to overall caffeine exposure. Caffeine also varies by sources tea leaves contain 1.5 to 3.5% caffeine kola nuts contain 2% caffeine and roasted coffee beans contain 0.75 to 1.5% caffeine.6 Coffee varies in caffeine content some analyses have estimated that caffeine may range from 0.8 to 1.8%, depending on the type of coffee.7 Crops of coffee, tea, and cocoa are very similar in their production periods and their useful life in production. Typically coffee, tea, and cocoa trees can be productive with crops every 5 years for a total period of 40 years,8 or an estimated 8 yields per tree. 

Total caffeine consumption will vary with a number of factors that are often difficult to disentangle. For caffeine exposure attributable to coffee, this includes brewing method and preparation type of coffee (Arabica, Robusta, instant), averaging to 1.3% caffeine for roasted beans 39 brand of coffee size of coffee cup and the volume of added ingredients, such as milk, cream sweeteners, and syrups. There are several different brewing or preparation techniques by which coffee can be prepared. Most notably, they differ in their final extraction of caffeine depending on the process. Filter coffee or automatic drip coffee results in approximately 97 to 100% caffeine extraction 37 however, regional differences in the volume of coffee... 

The data presented here has provided a chronological picture of the evolution and current state of the possible positive or negative association of some methylxanthine-containing products and various types of cancer. Perhaps the best conclusion at this time is an extension to tea and other methylxanthine-containing products of the statement by Stavric" who in 1990 wrote that certain controversial issues about the effect of coffee on human health remains unresolved. Future work should focus on types and methods of preparation of teas, roasting and preparation methods for coffees, and consider the whole beverage rather than caffeine or other methylxanthine per se. Meanwhile it appears that both tea and coffee and... 

The aluminum hydroxide crystals settle to the tank bottom, and are removed. The crystals are then washed to remove any caustic soda residues, vacuum dewatered, and sent on for calcination. In the calciners (a type of rotating kiln) the aluminum hydroxide is roasted for further dewatering. 

The heat transfer medium of the exchanger consisted of 1.6 mm (1/16") diameter, type A, 90% aluminum oxide ceramic beads (Coors Ceramic Co., Golden City, CO) with a specific gravity of 3.6 g/cm. Selected roasting conditions were maintained by control of bead temperature and resident time. The beads were heated to 240°C and were maintained in the chamber with the raw beans for 100 seconds in a 1 5 ratio of beans to beads. These processing conditions resulted in an exit temperature of the beans of 113°C. Roasted beans were cracked through a corrugated roller mill (Ferrell... 

Cake Donuts. The effects of 0-30% substitution of dry-roasted air-classified navy, pinto or black protein flour for wheat flour on the physical and sensory qualities of cake donuts were investigated. In general, fat absorption decreased as the level of substitution increased with the pinto bean variable having the lowest values. An increase of navy bean and pinto protein levels decreased donut height after the 10% level. The donuts with pinto bean protein exhibited less spread than the other bean type donut variables. Navy bean protein produced a more tender donut than the other bean types. The control donut and those with navy bean protein were the lightest in color, followed by pinto and black bean protein donuts,... 

Platelet Inhibition Ginger extract has been found to inhibit platelet aggregation induced by arachidonic acid, epinephrine, ADP, and collagen (Srivastava 1984). The extract s ability to inhibit cyclooxygenase activity and thromboxane levels correlated well with inhibition of platelet aggregation (Srivastava 1984 Mustafa et al. 1993). The type of preparation used also affects platelet inhibition, because roasted and charcoal of ginger were effective, while ether extracts of raw and dried ginger were not (Wu et al. 1993). 

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