Chocolate, bitterness

The natural moisture of the cocoa bean combined with the heat of roasting cause many chemical reactions other than flavor changes. Some of these reactions remove unpleasant volatile acids and astringent compounds, partially break down sugars, modify tannins and other nonvolatile compounds with a reduction in bitterness, and convert proteins to amino acids that react with sugars to form flavor compounds, particularly pyrazines (4). To date, over 300 different compounds, many of them formed during roasting, have been identified in the chocolate flavor (5). 

Theobromine was determined by GC in various foods (bitter chocolate, milk chocolate, chocolate cake, cocoa powder, chocolate milk), and results are given in graphs and tables.27 Homogenized samples were boiled in alkaline aqueous media, then fat was extracted with n-hexane. The aqueous layer was acidified with diluted HC1 and NaCl was added. Theobromine was extracted from this treated aqueous solution with dichloromethane and the extract was evaporated to dryness. The residue was redissolved in dichloromethane containing an internal standard. GC analysis was performed on a column packed with 1% cyclohexane dimethanol succinate on Gaschrom Q, with FID. Average recoveries were 99 to 101%, coefficient of variation was less than 3% and the limit of detection for theobromine in foods was about 0.005%. 

Chocolate liquor is the solid or semiplastic food prepared by finely grinding the nib of the cacao bean. It is commonly called baking chocolate, unsweetened chocolate, or bitter chocolate and, in Europe, is frequently referred to as chocolate mass or cocoa paste. Chocolate liquor is essentially the starting point from which all chocolate products are produced. Table 5 lists the theobromine and caffeine content of 22 various chocolate liquor samples determined by high pressure liquid chromatography (HPLC). The liquors averaged 1.22% theobromine and 0.214% caffeine.27- 28 The ratio of theobromine to caffeine ranged from 2.5 1 to 23.0 1. 

Bitter Anise, coffee, chocolate, mint, grapefruit, cherry, peach,... 

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I have always liked chocolate. I grew up on it. Every morning my mother blended a heaping spoonful of cocoa powder with a little milk, some sugar, and a touch of salt (to decrease the bitterness). Then she stirred the mix into gently boiling... 

SHAVE A SMALL SQUARE OF BAKER S CHOCOLATE OR BITTER CHOCOLATE INTO FINE BITS. 

There are many phenolic substances in plants and thus in foods. Rich dietary sources of phenolics include fruits, tea, coffee, cocoa, and processed foods derived from these, such as wine. At high levels, and in particular when sugar levels are low, phenols impart an astrin-gency, bitterness, and color to foods. In red wine, unsweetened tea, and chocolate products, the taste is heavily influenced by the presence of phenolics. Therefore, an assessment of phenolic content in food is of great importance. 

The Folin-Ciocalteau (FC) procedure is one of the standard procedures in wine analysis, as well as in tea analysis (Wiseman et al., 2001). One drawback in interpretation is that different classes of phenolics have varying taste attributes, and tests for chemical astringency based on precipitation of proteins have been recently developed (Adams et al., 1999). In addition, if the food product contains sugar, it can mask the bitterness and astringency, as observed in ripe fresh fruit, sweetened chocolates, and tea. 

Caffeine, the active substance responsible for the stimulant effect of the coffee plant s berry, is a methyl-xanthine, one of the family of stimulants present in more than 60 species of plants. The pure chemical forms white, bitter-tasting crystals, which were first isolated from coffee in 1820. Other family members are theophylline, found in tea leaves, and theobromine, found in the cacao pods that are ground to make chocolate. The most potent component in the coffee family by unit weight is theophylline, while theobromine, the weakest component by unit weight, stays in the body longer than does caffeine. 

Chocolate is a solid-in-oil (S/O) suspension of non-fat partides (of about 10-100 (im diameter) of sugar and cocoa (cacao) in a continuous phase of cocoa butter, which is the natural fat from the cocoa bean [215]. When cocoa beans are cleaned, roasted, cracked and ground, chocolate liquor results, a suspension of cocoa powder in cocoa butter. Depending on how much cocoa butter is removed (by pressing) one can make, in decreasing order of cocoa butter content bitter, unsweetened, baking... 

Theobromine was isolated from the seeds of the cacao tree and then shortly afterward was synthesized from xanthine by Fischer.132 Theobromine is the primary bitter-tasting alkaloid found in cocoa and chocolate chocolate contains 0.5—2.7% theobromine. Theobromine is water insoluble and is an isomer of theophylline as well as paraxanthine. Theobromine is categorized as 3,7-dimethylxanthine while theophylline is 1,3-dimethyl-7f/-purine-2,6-dione and paraxanthine is 1,7-dimethylxanthine. Theophylline is known to be a bitter-tasting principle of green tea. Theobromine is used as a vasodilator (a blood vessel widener), as an aid in urination, and... 

Despite the supposed universality of bitter taste rejection, many commonly consumed foods and beverages such as fruits, tea, coffee, chocolate, and alcohol have bitterness as a major sensory attribute which, in the overall taste profile of a food, is often appreciated by the consumers. Some alkaloids are certainly responsible for the bitter taste of known food the taste threshold is available only for atropine (0.1 mM), cocaine (0.5 mM), and morphine (0.5 mM) (Table 3.1). 

Van Houten developed two processes, one in 1928 in order to separate physically, cocoa butter and cocoa solids (which were then transformed to make the famous cocoa powder) the other is the alkali treatment of chocolate to remove bitterness ... 

One of the most famous sources of caffeine is chocolate, also made from the seeds of a tropical tree. Chocolate, which contains a lot of fat and is very bitter, must be mixed with sugar to make it palatable. It, too, contains a stimulating drug, and cases of chocolate dependence are easy to find. You probably know a few "chocoholics." People who regularly consume chocolate or go on chocolate-eating binges may not realize they are involved with a drug, but their consumption usually follows the same sort of pattern as with coffee, tea, and cola drinks. 

Caffeine is a bitter-tasting compound found in coffee, tea, cola beverages, and chocolate. Caffeine is a mild stimulant, usually imparting a feeling of alertness after consumption. It also increases heart rate, dilates airways, and stimulates the secretion of stomach acid. Caffeine is an alkaloid, a naturally occurring amine derived from a plant source. In Chapter 25 we learn about the properties and reactions of amines. 

It would be rash indeed to be on the "dark flavor of the month" (except perhaps bitter chocolate). A unified dark sector proposal (77) was noted at the end of the previous section. Raman Sundrum (88) has given the graviton a finite size and urged that searches for deviations of the gravitational force from 1/R2 be continued down to the 20 pm scale. The difficulty with such experiments (89) is in getting the centers of two very... 

I carried through with the lie to the bitter end, I don t think there were any suspicions, and I myself boarded a train for the Grand Canyon to be (l)out of reach when the chocolate hit the fans and (2)in a nice spot in case of the highly unlikely event that the Millennium was actually going to begin that day. it didn t, and the feedback from the experiment was less than respectful. My former partners disappeared from the scene to cope with more petty problems and new coincidences materialized out of nowhere to enable the next stage of my ongoing quest. 

Plain or bitter chocolate is a mixture of ground cocoa nibs with sucrose, cocoa butter and flavouring. Milk chocolate contains in addition milk powder. A bar of chocolate contains about 6 mg of caffeine and a cup of cocoa about 13 mg. 

When chocolate, for example, is roasted, calfeine and other compounds are formed that stimulate the bitter taste cells. The molecules of these compounds have a shape that allows them to attach to the taste cell receptors and cause an adjacent nerve cell to fire. This event sends the bitter signal to the brain. 

Sugar is added to chocolate to counteract the bitter taste. The arrangement of atoms in sugar molecules allows them to fit into the receptor sites of sweet taste cells. When a sugar molecule such as glucose or sucrose attaches to a receptor of a sweet taste cell, the sweet signal is sent to the brain. 

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