Chocolate, antioxidants

Figure 4. Antioxidant capacity and lipid oxidation in plasma of volunteers consuming different amounts of procyanidin-rich dark chocolate (6.9 mg of procyanidins per g of chocolate). Antioxidant capacity was evaluated by the ability of plasma to inhibit luminol-dependent chemiluminescence and lipid oxidation by plasma TEARS. Plasma epicatechin concentrations are the average amount of epicatechin determined two hours after chocolate consumption. Ordinate values indicate increases over basal levels of plasma antioxidant capacity (white bars), or decrease over basal values for TEARS (gray bars).

The body maintains an antioxidant network consisting of vitamins A, C, and E, antioxidant enzymes, and a group of related compounds called coenzyme Q, for which the general formula is shown below. The n represents the number of times that a particular group is repeated it can be 6, 8, or 10. Antioxidants are molecules that are easily oxidized, so they react readily with radicals before the radicals can react with other compounds in the body. Many common foods, such as green leafy vegetables, orange juice, and chocolate, contain antioxidants, as do coffee and tea. 

Serafini M, Bugianesi R, Maiani G, Valtuena S, De Santis S and Crozier A. 2003. Plasma antioxidants from chocolate. Nature 424(6952)4013. 

Adamson, G.E. et al., HPLC method for the quantification of procyanidins in cocoa and chocolate samples and correlation to total antioxidant capacity, J. Agric. Food Chem., 47, 4184, 1999. 

A 12-fold increase in plasma epicatechin concentration from 22 to 257 nmol/L was reported by Rein et al [105] after consumption of 80 g semisweet (procyanidin rich) chocolate within 2 h after ingestion. The total antioxidant capacity of plasma increases of 31% within the same time, and plasma 2-thiobarbituric acid reactive substances decreased up to 40%. These data support that consumption of chocolate increases plasma epicatechin concentrations and decreases plasma baseline oxidation products. These results have been confirmed in another study by Wang et al [106]. 

Dr. Joe Vinson of the University of Scranton believes that there is something to the chocolate effect, and he came to Belmont to tell us about his intriguing research. Vinson has determined the total polyphenol content of various chocolates and has also found a way of measuring how effective these mixtures are in preventing the oxidation of human ldl in a test tube. In other words, he has calculated a phenol antioxidant index, which takes into account both the quantity and the quality of these desirable substances. At the symposium Vinson reported that cocoa powder and dark chocolate are the best, followed by milk chocolate. Instant cocoa mixes trail the field. Then Vinson delivered the kicker chocolate has more, and better, polyphenols than fruits or vegetables and more than red wine. A forty-gram bar of dark chocolate has as many polyphenols as a cup of that widely promoted antioxidant cocktail we call tea. But there is still the matter of chocolate s fat content. Researchers tell us, though, that at least half of it is stearic acid, which does not raise blood cholesterol. 

Sanbongi C, Suzuki N, Sakane T. 1997. Polyphenols in chocolate, which have antioxidant activity, modulate immune functions in humans in-vitro. Cell Immunol 177 129-136. 

Chocolate has antioxidant properties for low-density lipoproteins and hence could prevent heart disease. Foods and beverages derived from cocoa beans have been consumed by humans since 460 a.d. Cocoa pods from the cocoa tree (Theobroma cacao) are harvested and the beans removed and fermented. Dried and roasted beans contain about 300 chemicals including caffeine, theobromine, and phenethylamine. Chocolate liquor is prepared by finely grinding the nib of the cocoa bean and is the basis for all chocolate products. Cocoa powder is made by removing part of the cocoabutter from the liquor. Bittersweet chocolate, sometimes called dark chocolate, contains between 15 and 60% chocolate liquor, the remainder being cocoa butter, sugar, and other additives. Milk chocolate is the predominant form of chocolate consumed in the U.S. and typically contains 10 to 12% chocolate liquor. 

The appeal of chocolate is universal, but the pleasures of eating chocolate products may perhaps be tempered by their fat and sugar content. However, in a series of human feeding studies it has been shown that the high proportion of stearic acid in the cocoa butter of chocolate does not adversely affect plasma lipids. Two recent reports of antioxidant activity have increased interest in the health aspects of chocolate an in vitro low-density liposprotein (LDL) oxidation study and a short-term in vivo study. Epicatechin, the major monomeric polyphenol antioxidant in chocolate, and an extract of chocolate liquor were both found to stimulate cellular immune response in vitro. 

Polyphenol consumption as flavonoids has been shown to decrease the risk of heart disease in a cross-cultural epidemiological study. Most recently, an epidemiological study found that Harvard male graduates who ate a moderate amount of chocolate and other candy had a 36% lower risk of death compared with non-candy eaters. The authors speculate that it is the antioxidants present in the chocolate that provide a health benefit. 

The quality of the phenol antioxidants was assessed by Vinson et al. (1999) using the IC50 for LDL + VLDL (very low density lipoprotein) oxidation, with smaller values indicating a higher quality. Quality of the antioxidants was due to free-radical scavenging activity and not chelation as the concentration of polyphenols for 50% inhibition was < 1 xM and cupric ion 25 xM in the oxidation medium. There was less percent variation within the groups for this parameter than for the total polyphenol content. The quality order was dark chocolate > cocoa > milk chocolate. The dark chocolate and cocoa were significantly different from the milk chocolate (p < 0.05), but not... 

An important antioxidant parameter with respect to head disease is the lipoprotein-bound antioxidant activity. The value for epicatechin, a polyphenol component of chocolate, was 63% greater than the control average, and increase in lag time for the three representative chocolate products was 41%. All beverages, such as wine and tea, that had this antioxidant activity were also found to produce an increase in lag time after ingestion. 

The increase of use of fruits and vegetables, or the moderate use of foods rich in antioxidants (such as extra virgin olive oil, tea, wine, coffee, black chocolate, etc.) can substitute for the use of supplement once OS is under control,... 

Maltol has antioxidant properties. It has been found to prolong storage life of coffee and roasted cereal products. Maltol is used as a flavor enhancer in chocolate and candies, ice cream, baked products, instant coffee and tea, liqueurs, and flavorings. It is used in concentrations of 50 to 250 ppm and is commercially produced by a fermentation process. 

Gu, L. House, S.E. Rooney, L.W. Prior, R.L. 2008. Sorghum extrusion increases bioavailability of catechins in weanling pigs. J. Agric. Food Chem. 56 1283-1288. Gu, L. House, S.E. Wu, X. Ou, B. Prior, R.L. 2006. Procyanidin and catechin contents and antioxidant capacity of cocoa and chocolate products. J. Agric. Food Chem. 54 4057-4061. 

Commercial lecithin products that were sold many decades ago for applications such as chocolate and confectionery products, margarine, bakery goods, pasta products, textiles, insecticides, and paints are still active today because of their emulsifying, wetting, colloidal, antioxidant, and physiological properties. Lecithin s multifunctional properties and its natural status make it an ideal food ingredient. The major applications and functional properties of lecithin products are shown in Table 25 (7). 

The confectionery industry utilizes the emulsification, antistick, and viscosity properties of lecithin and benefits from the concurrent effects of shelf-life extension, texture improvement, and decreased production costs (83). A product such as caramel will not blend correctly in the absence of lecithin. Uniform dispersion of fat, aided by lecithin, will decrease stickiness and provide tenderness for ease of cutting. The natural antioxidant properties of lecithin slow the decay of any product in which it is incorporated. Viscosity is very important in the chocolate industry where shape is often a requirement for consumer acceptability. High concentrations of butter, such as cocoa butter, impart high viscosity, which in turn makes... 

While the positive health benefits associated with the consumption of a flavonoid-rich diet cannot be attributed to any one factor, the antioxidant properties of certain flavonoids have been the focus of considerable attention [8]. The antioxidant actions of chocolate flavonoids were first studied inhibiting LDL-oxidation [9,10]. As a consequence of the availability of purified procyanidins from cocoa (dimer-decamer), this particular family of... 

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