Cacao processing

Besides their general flavor forming potential peptides are also reported to be unique precursors of composite food aromas. Peptides formed in the fermentative stage of cacao processing have been linked to roast generated chocolate aroma (5). Also, a methionine rich polypeptide has been associated vith roasted peanut volatiles (15). 

The terms cocoa and cacao often are used interchangeably in the Hterature. Both terms describe various products from harvest through processing. In this article, the term cocoa will be used to describe products in general and the term cacao will be reserved for botanical contexts. Cocoa traders and brokers frequendy use the term raw cocoa to distinguish unroasted cocoa beans from finished products this term is used to report statistics for cocoa bean production and consumption. 

The second major technical development occurred in 1876, when milk chocolate was invented in Switzerland by M. D. Peter. This process provided a new stimulus to the cacao trade. Milk chocolate powder and cocoa butter were later combined to make an eating chocolate that formed the backbone of the chocolate industry today. 

After the ripe pods are harvested, they are cut open and the beans and adhering pulp are removed for fermentation. It is during the process of fermentation that cacao acquires much of its characteristic flavor and aroma. Fermentation soon occurs due to the high sugar content of the pulp and the presence of microorganisms. The sugars are converted to alcohols and finally to acetic acid, which drains off. The acetic acid and heat formed... 

Although low levels of methylxanthines have been detected in the leaves and flowers of T. cacao, the primary storage location is within the seed or bean.16 The cocoa bean is the major natural source of the methylxanthine theobromine, but contains only small amounts of caffeine. Theophylline has been detected in cacao beans, but at such low concentrations that its presence generally is ignored. Together, theobromine and caffeine account for up to 99% of the alkaloid content of T. cacao beans. Alkaloid content is affected by genetic makeup, maturity of beans at harvest, and fermentation process. Analytical methodology also is partially responsible for some of the disparity in methylxanthine values since many early methods were unable to separate theobromine and caffeine. 

After fermentation, cacao beans are dried and then transported to the factory for roasting. The ultimate purpose of roasting is to develop desirable bean flavor and aroma, as well as the necessary texture for later grinding. As shown in Table 4, the methylxanthine content of cacao beans was not found to change significantly during the roasting process.5-24 26... 

This chapter has compiled and evaluated information on the methylxanthine composition of cocoa and various chocolate foods and beverages, as well as the consumption pattern for these commodities. Cacao is the major natural source of the xanthine base theobromine. Small amounts of caffeine are present in the bean along with trace amounts of theophylline. Numerous factors, including varietal type and fermentation process, influence the methylxanthine content of beans. 

Different authors used RP-HPLC and UV detection to monitor peptide formation during cheese ripening [174-178], providing valuable information about proteolysis. When large hydrophobic peptide need to be separated an lEC represents the best choice [179]. Nevertheless, the identification of these peptides is essential for the complete understanding of the proteolytic process. The peptides eluted from the LC column can be subjected to ESl-MS for molecular weight determination and MS/MS for amino acid sequence determination, which allow rapid peptide identification [172]. HPLC-ESl-MS and MS/MS techniques have been successfully used for peptide mass fingerprint purposes for sequence analysis of purified albumin from Theobroma cacao seeds [180,181]. 

A similar apparatus has been used for recovery of aroma compounds from cacao during processing [34]. In this process, water and acetic acid are removed from the aroma-laden gas stream by the initial traps and then the gas is passed through traps of the same design as those described by Cams and Tuot [29]. The aroma isolate so provided is suggested to be useful for the flavouring of soluble cocoa beverages, cake mixes, and confectionery products. 

Cocoa butter NF is defined as the fat obtained from the seed of Theobroma Cacao Linne (Family Sterculiaceae) (44). Cocoa butter softens at 30°C and melts at 34°C. It contains four different forms alpha, beta, beta prime, and gamma with melting points of 22°C, 34°C to 35°C, 28°C and 18°C, respectively. The beta form is the most stable and is desired for suppositories. The biggest challenge with the polymorphism of cocoa butter is the impact of the manufacturing process on the characteristics of the suppository itself. When cocoa butter is hastily melted at a temperature greatly exceeding the minimum required temperature and then quickly chilled, the result is metastable crystalline form (a crystals), which may not even... 

Although cocoa as a drink is now rather unfashionable, it provides the raw material for the manufacture of chocolate and is commercially very important. Cocoa (or cacao) is derived from the roasted seeds of Theobroma cacao (Sterculiaceae), a tree widely cultivated in South America and West Africa. The fruits develop on the trunk of the tree, and the seeds from them are separated, allowed to ferment, and are then roasted to develop the characteristic chocolate flavour. The kernels are then separated from the husks, ground up, and processed in various ways to give chocolate, cocoa, and cocoa butter. 

Maillard reactions can be involved in the manufacture of foods in at least three quite different ways. First, there is the unconscious role played in the development of flavor in such traditional processes as the roasting of coffee and cacao beans, the baking of breads and cakes, and the cooking of meats. Second, there is the deliberate use of Maillard technology in the production of artificial (or engineered) foods and flavors. Third, there are the efforts to inhibit undesirable results of Maillard reactions in food processing today. 

One of the world s most popular flavors is determined by a physical-chemical composition which starts with the seeds of the plant, Theobroma cacao, and continues with an empirical process discovered and perfected by the Aztecs, or by an earlier society from whom the Aztecs received it. 

There is no evidence that any of the manufacturers of cocoa and chocolate have adapted any part of the Maillard technology to their manufacturing processes. There are at least two reasons for this. First, the standard processes, as applied to beans of good quality, produce excellent products. Second, while the work just reviewed has given us a rather clear outline as to how chocolate aroma is developed in the roasting of fermented beans, the research work has not yet been done, or reported, that would serve as a basis for improving the industrial processing of cacao beans. 

Li et al [2] are trying to improve the extraction process adding a co-solvent, ethanol, to Carbon dioxide to enhance the concentration of caffeine and especially of theobromine in the solvent by orders of magnitude thus reducing time and quantity of solvent to be cycled. In the same way the concentration of cacao butter in the solvent is increased. Consequently the xanthines and fats are extracted simultaneously. Moreover they monitored solubilities of the important ingredients theobromine, caffeine and cacao butter. 

Watterson, J.J., Miller, K.B., Fuijanic, J.J., Stuart, D.A. Process of producing cacao flavor by roasting combination of amino acids and reducing sugars. US Patent, 1997, 5,676,993, assigned to Hershey Foods. 

However fascinating is the history of cacao, its acceptance in our current practical lives scarcely gives due credit to the exalted status it enjoyed in the ancient Central American cultures. Social custom and traditions passed over into and shaped its acceptance in our European culture, and in many countries it still constitutes an expensive luxury. Poetry and music, as esthetic forms of literature, have not neglected cacao and chocolate as themes. However, commercial exploitation and technological advances in agriculture and the manufacturing and processing arts and sciences constitute the major portion of our literature on this subject today. 

Watrous, R. C., Cacao, A Bibliography on the Plant and Its Culture and Primary Processing... 

Tea is made by processing the leaves of the tea tree Camellia sinensis, which originated in the southern areas of Yunnan province in China, and is now spread throughout the world. This plant has been used as a medicine for 5,000 years, and was probably first selected because its leaves contain a high concentration of caffeine. Caffeine is a central nervous system stimulant, and other caffeine-containing plant products, such as coffee beans, cacao beans, guarana berries, kola nuts, and mate leaves, have been selected and used to make beverages by people on various continents. 

C 46,66%, H 4.48%, N 3j.l0%, O 17.76%. The principal alkaloid of the cacao bean which contains 1.5-3% of the base. Also preseot in cola nuts and io tea- Usually extracted from the hull of cacao beans which contains 0.7 -1.2%, Extraction process Schwyzer, Die Fabrication Phar-... 

At one time, the process ended here. One simply mixed the liquor with water to produce a bitter beverage that was marred by a layer of oil that floated on top. This is where Van Houten stepped in. He invented a hydraulic press that squeezed the cacao fat out of the chocolate liquor. The residue of this process Van Houten pulverized to a fine powder. The beverage it produced was still bitter, but Van Houten found that treating the powder with sodium bicarbonate or ammonium hydroxide... 

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