Acrylamide and Tea: Four Surprising Facts

If you're looking for ways to reduce your exposure to acrylamide, ditch your daily coffee routine and start drinking green tea instead! Unlike coffee, tea does not contain acrylamide, a carcinogenic compound that is concentrated in roasted coffee beans. Acrylamide starts to form in foods when they are exposed to high temperatures, such as during roasting, toasting, or grilling. Research shows at a temperature of 120 degrees Celsius (248 Fahrenheit) is required for formation of this toxin.

Tea, both green and black tea, is made by drying leaves of the Camellia sinensis plant in low temperature conditions. And in case you wonder what gives black tea its intense dark color, it's not roasting but the unique process used to manufacture black tea. Here's a quick primer on the manufacturing process of black tea: After the leaves of the tea plant are harvested, they are spread on large racks and let to wilt and dry for several hours. Some tea manufacturers let the leaves dry in cooler conditions, while others let them dry in the sun. In both cases, the temperatures are way too low to trigger acrylamide formation. Once the tea leaves are dry, they are rolled and bruised or torn and curled to release some of the essential oils they contain. When the essential oils come in contact with air, the leaves begin to oxidize, giving the leaves the dark brown color characteristic of black tea.

As an added bonus, not only is tea free of acrylamide, it also appears to have anti-acrylamide properties. A group of Saudi Arabian scientists conducted a study to investigate the effects of green tea extract on liver function in rats that were administered acrylamide. They found that the tea extract provided increased protection in liver cells and liver cell membranes against the cell-damaging effects of acrylamide. The results of this study don't come as a surprise. Green tea is known to contain antioxidants such as the epigallocatechin-3 gallate (EGCG) which has been shown to be extremely effective at reducing the damaging effects of free radicals. Most of the well-documented health benefits of green tea are linked to the high concentration of EGCG found in this healthy beverage, but there are also a number of other flavonoids that may contribute to the extraordinary antioxidant prowess of green tea.

Another study found that addition of green tea extract could even reduce the formation of acrylamide in the test food (doughnuts) – in addition to increasing the antioxidant properties of the food. However, the researchers responsible for this study pointed out that the green tea extract appeared to reduce the formation acrylamide only at very specific levels (0.25 grams or 0.5 grams per 100 grams of doughnut). Very low concentrations and very high concentrations of green tea extract, in contrast, appeared to actually increase the acrylamide content of doughnuts.

Sources:
1. Journal of American Science, 2011; 7. A Trial of Using Green Tea for Competing Toxicity of Acrylamide on Liver Function, Thanaa A. El- Kholy, Nahlaa A. Khalifa, A.K. Alghamidi, and Arwa M. Badereldin, Journal of American Science, 2011; 7.
2. Budryn, G, et al (2013). Influence of addition of green tea and green coffee extracts on the properties of fine yeast pastry fried products. Food Research International, Jan 2013.