Scientists propose new process for high-flavonoid cocoa
Filed Under News May 29, 2007
Scientists in Spain are reporting development of a new process to make cocoa powder with eight times the levels of some flavonoids linked to chocolate’s beneficial effects.
Writing in the Journal of Agricultural and Food Chemistry Juan Carlos Espin de Gea and colleagues report that omitting the traditional fermentation and roasting steps used in the processing of cocoa beans can achieve higher levels of flavonoids.
The researchers, including scientists from cocoa-ingredient manufacturer Natraceutical Group, also tested the bioavailability of these flavonoids in humans and found to be five-fold higher than from a conventional cocoa powder.
“All of these studies confirm that through improved processing, the flavonoid composition of cocoa powder can be enhanced (mainly flavanol monomers and dimers) and that this enhancement leads to an increase in the cocoa flavonoid metabolites present in plasma and in urine showing a higher bioavailability,” wrote the authors.
The health benefits of antioxidant-rich chocolate have received much recognition in recent years, with positive findings from a number of studies impacting on consumer awareness. Chocolate manufacturers are using high cocoa content (over 70 per cent) as a means of differentiation, and cocoa has also received attention for its potential in functional food applications.
The flavonoid-enriched cocoa powder was prepared by blanching the fresh cocoa beans in hot water in order to inactivate the polyphenol oxidase enzyme that is responsible for the oxidation of polyphenols in the bean. The beans were then dried, deshelled, milled, partially defatted, and vacuum-dried.
Comparison with conventional cocoa powder showed that the flavonoid-rich powder contained four times more procyanidins, and eight times more epicatechin and procyanidin B2, than the conventional powder.
To test the bioavailability of these flavonoid six healthy volunteers consumed a milk drink made with flavonoid-enriched cocoa. The same volunteers later drank chocolate milk made from traditional cocoa. Blood and urine tests established the bioavailability of flavonoids in the enriched-milk drink, and showed that epicatechin glucuronide (the main metabolite detected in the blood) was five-fold higher following consumption of the flavonoid-rich powder than the conventional powder.
“Previous reports have linked the cardiovascular beneficial effects of cocoa consumption with the accumulation of procyanidin metabolites in plasma,” said the researchers.
“In this context, a higher health beneficial effect upon the intake of a cocoa-derived product based on a process that preserves flavonoid content cannot be ruled out,” they concluded.Source: Journal of Agricultural and Food Chemistry
Published on-line ahead of print, doi: 10.1021/jf070121j
“A New Process to develop a Cocoa Powder with Higher Flavonoid Monomer Content and Enhanced Bioavailability in Healthy Humans”
Authors: F.A. Tomas-Barberan, E. Cienfuegos-Jovellanos, A. Marin, B. Muguerza, A. Gil-Izquierdo, B. Cerda, P. Zafrilla, J. Morillas, J. Mulero, A. Ibarra, M.A. Pasamar, D. Ramon, J.C. Espin Stephen Daniells
Organic foods contain higher nutrient levels
Filed Under News May 21, 2007
Organic crops have recently been deemed by scientists to contain higher nutrient levels than conventional ones. In a recent analysis of fruits by various European countries and led by the University of Newcastle, organic tomatoes, apples and peaches the fruits showed greater concentrations of these valuable nutrients.
Although organic tomatoes appeared to be lower in lycopene, they were higher in vitamin c, beta-carotene, and flavonoids than non-organic ones in tests conducted by researchers at Warsaw Agricultural University. It was also discovered that apple puree, which is a popular choice for babies, contained more flavonoids, vitamin C, and phenols than regular apples.
French researchers contributed to the study. By examining organic peaches and finding at the time of harvest they had higher polyphenol content they gave evidence that organic if both healthier and tastier.
Research Suggests Chocolate Is Healthy
Filed Under News May 14, 2007
A growing body of research suggests that certain compounds in chocolate can have a host of health benefits.
“We have heard how chocolate may be associated with a cardioprotective effect, and that it may lower blood pressure and reduce cholesterol,” said Dr. Randall Zusman, director of Massachusetts General Hospital’s division of hypertension.
“From my perspective, it is interesting that a natural product, especially something like chocolate, may have a beneficial effect.”
The positive effects shown thus far are predominantly associated with substances called flavonoids, which are abundant in raw, unprocessed chocolate.
These substances are thought to be potent antioxidants — chemicals in food that have shown promise in halting the destructive action of free radicals in the body, which may lead to cancer.
Antioxidant Found in Red Wine, Kills Cancer Cells in Experiments
Filed Under News May 4, 2007
A pigmentation chemical that makes grape skins and wines red has been found to kill human leukemia and lymphoma cells cultured in a lab, according to research to be published May 4 in the Journal of Biological Chemistry. However, the compound, a type of anthocyanidin common in plants, left healthy blood cells alone.
“Current treatments for leukemia, such as chemotherapy and radiation, often damage healthy cells and tissues and can produce unwanted side effects for many years afterward,” said coauthor Dr. Xiao-Ming Yin, an associate professor of pathology at the University of Pittsburgh School of Medicine. “So, there is an intensive search for more targeted therapies for leukemia worldwide.”
There are several different types of leukemia, a cancer of the blood or bone marrow typically characterized by an uncontrolled increase in white blood cells (which, when functioning normally, help defend the body from disease). About 44,000 new leukemia cases will be diagnosed in the United States in 2007, and there will be about 22,000 leukemia-related deaths according to the National Cancer Institute.
Yin and his team focused on one of the most common anthocyanidins, which are forms of anthocyanin, water-soluble flavonoids that provide color to flowers, leaves, fruits and vegetables. In grapevines, anthocyanidin is believed to play a part in attracting honeybees to the vines’ flowers, as well as serving as a natural sunscreen by protecting against high levels of ultraviolet radiation. Previous studies, the authors added, have shown that anthocyanidins work as antioxidants by helping to eliminate damaging rogue oxygen molecules, called free radicals.
For this latest experiment, Yin and his team studied the effects and the mechanisms of cyanidin-3-rutinoside (C-3-R), to see how it behaves in the presence of cancer. The C-3-R was extracted and purified from black raspberries, though it also abounds in red wine, and was used in much higher amounts than the typical red wine drinker would be able to consume.
The C-3-R was tested on several lines of human leukemia and repeated using cell cultures of lymphoma, another immune system–based cancer. The scientists observed that, at low doses of C-3-R, half of the cancer cells in all of the lines died within 18 hours of treatment. At higher doses, the C-3-R killed all of the cells by the end of the 18-hour period. The experiment was repeated several times, on different types of leukemia cancer cells, with similar results.
Yin’s team found that C-3-R caused the cells to produce peroxides, a type of free radical that, in turn, activated a pathway within the cancer cells that caused them to die. In contrast, when the researchers treated normal human blood cells with C-3-R, they did not find any increased accumulation of free radicals and there were no apparent toxic effects on these cells.
“Therefore, if we can reproduce these anticancer effects in animal studies,” Dr. Yin said, “this will present a very promising approach for treating a variety of human leukemias and, perhaps, lymphomas as well.”
Organic food is better for you, say scientists
Filed Under News May 4, 2007
New evidence has emerged showing that organic food does contain nutrients that deliver health benefits, contrary to the view put forward earlier this year by David Miliband, who said it was only a “lifestyle choice”.
Scientists in Britain, France and Poland examined organic carrots, apples, peaches and potatoes and discovered that they have greater concentrations of vitamin C and chemicals that protect against heart attacks and cancer than non-organic produce. The research could challenge official government guidelines which suggest there is no evidence of organic food being healthier than conventional produce. That led to the assertion by Mr Miliband, the Environment Secretary, which he later qualified by saying that he ate organic food both because of its taste and the environmental benefits.
The new studies found that organic tomatoes had more vitamin C, beta-carotene and flavonoids, which are known to help against cancer and heart disease, though they also had less lycopene, which is thought to help prevent skin ageing, diabetes and osteoporosis. Organic apple puree was found to contain more phenols, flavonoids and vitamin C than non-organic versions.
“This research shows there are benefits,” said Dr Kirsten Brandt of Newcastle University, which led the research. “The reason why it’s such a grey area is because it’s extremely difficult to measure the health benefit in any food, but we can say that if you eat 400g of fruit and vegetables per day you would get 20 per cent more nutrients in organic food.”
Flavonol rich diet may reduce pancreatic cancer risk
Filed Under News May 3, 2007
A diet rich in flavonols from foods such as onions, apples and berries may cut the risk of developing pancreatic cancer by about 25 per cent, scientists have told attendees at the Annual Meeting of the American Association for Cancer Research.
And the benefits may be even more pronounced amongst smokers, with a risk reduction of over 59 per cent, said lead author Ute Nöthlings from the German Institute of Human Nutrition Potsdam-Rehbruecke.
According to the US National Cancer Institute almost 38,000 new cases of pancreatic cancer are diagnosed every year in the US, with almost 34,000 deaths from the disease. British charity Cancer Research UK states that the pancreatic cancer has a poor prognosis overall since most cases are diagnosed quite late. Indeed, only one in every 50 cases will still be living five years after diagnosis, highlighting the importance of prevention for this type of cancer.
The new study, part of the Multiethnic Cohort Study of 183,518 residents of California and Hawaii, reports that subjects with the highest consumption of flavonols from the diet had significant risk reductions, compared to the lowest consumption, with smokers particularly benefiting from flavonol-rich diets.
“The effect was largest in smokers, presumably because they are at increased pancreatic cancer risk already,” said Nöthlings. Smoking is the only established risk factor for pancreatic cancer, and “short of stopping tobacco use, it has been difficult to consistently show lifestyle factors that might help protect against this deadly cancer,” she added.
The researchers, led by Laurence Kolonel from the Cancer Research Center of Hawaii, used food frequency questionnaires to assess dietary intakes and followed them for an average of eight years, with 529 incident cases of pancreatic cancer documented in the study population.
The researchers also stated that theirs is the first study to examine prospectively specific classes of flavonols (quercetin, found in onions and apples; kaempferol, found in spinach and some cabbages; and myricetin, found mostly in red onions and berries) and pancreatic cancer risk.
Of the three individual flavonols, they report that kaempferol was associated with the largest risk reduction (22 per cent) across all participants. The interaction with smoking status was statistically significant for total flavonols, quercetin and kaempferol. The extended benefits afforded to smokers did not appear to extend to former smokers, said Nöthlings.
While no mechanistic study was performed by the researchers, Nöthlings stated: “Anti-carcinogenic effects of flavonoids in general have been attributed to the ability of these constituents to inhibit cell cycle, cell proliferation and oxidative stress, and to induce detoxification enzymes and apoptosis.”
“Further epidemiological studies in other populations and geographic regions are needed to confirm our findings,” she said.
Interest in flavonoids is growing rapidly and a mounting body of science, including epidemiological, laboratory-based and randomised clinical trials, continues to report the cancer-fighting potential of a number of different flavonoids, such as isoflavones, anthocyanidins and flavonols.
Source: Annual Meeting of the American Association for Cancer Research
April 2007, Abstract 856
“Flavonols and pancreatic cancer risk: The Multiethnic Cohort Study”
Authors: U. Nöthlings, S.P. Murphy, L.R. Wilkens, B.E. Henderson, L.N. Kolonel.
Dark Chocolate Antioxidants
Filed Under News May 1, 2007
Laboratory studies demonstrate powerful antioxidant effects from a group of cocoa bean compounds called flavonoids. The flavonoid “family” also includes such health-protective compounds as the resveratrol in grape juice and EGCG in green tea. When people consume chocolate and cocoa, the amount of antioxidants in their blood increases.
Studies also show that oxidation of LDL cholesterol, a process that converts cholesterol to a form more damaging to blood vessels, is slowed. Other studies suggest that chocolate’s antioxidant action could protect our DNA from damage that can develop into cancer. Chocolate’s flavonoids provide additional heart health benefits by improving function and flow through blood vessels.
Yet the flavonoid content of chocolate is highly variable. Dark chocolate, which can be bittersweet and semi-sweet, is usually 50 to 85 percent cocoa (which includes cocoa bean solids plus cocoa butter), is high in flavonoids and has an intense flavor. Dark chocolate is less sweet than other types of chocolate because as cocoa content goes up, sugar content drops. Milk chocolate can range from 7 to 50 percent cocoa. White chocolate contains no cocoa bean solids (and therefore is not a source of flavonoids), but does contain cocoa butter.
Research suggests health benefits from drinking cocoa, too. One study comparing total antioxidant activity from single servings of cocoa, green tea, black tea and red wine, reported cocoa markedly higher than the rest. However, most widely available cocoa mixes contain treated cocoa (called Dutch cocoa) that produces a richer taste but contains much fewer antioxidants.
