Tuna are several species of ocean-dwelling fish in the family Scombridae. Tuna are fast swimmers and like most other fish species are cold-blooded. Unlike most ocean fish species, which have white flesh, the flesh of tuna is pink. This is because the tuna's blood has a higher oxygen carrying ability than other fish species. Some of the larger tuna species such as the bluefin tuna can raise their blood temperature above the water temperature with muscular activity. Though not really warm-blooded, this enables them to live in cooler waters and survive a wider range of circumstances. Tuna, an excellent source of lean protein, vitamins and minerals but also is low in saturated fats and cholesterol. Tuna can also help lower blood pressure and cholesterol. Research has shown that omega-3 fatty acids, found in abundance in fatty fish like tuna can help lower the risk of heart disease, ease the pain of arthritis, reduce asthma complications, and is essential in the growth and development of young children. Tuna are several species of ocean-dwelling fish in the family Scombridae. Tuna are fast swimmers and like most other fish species are cold-blooded. Unlike most ocean fish species, which have white flesh, the flesh of tuna is pink. This is because the tuna's blood has a higher oxygen carrying ability than other fish species. Some of the larger tuna species such as the bluefin tuna can raise their blood temperature above the water temperature with muscular activity. Though not really warm-blooded, this enables them to live in cooler waters and survive a wider range of circumstances. Mercury levels are oftentimes relatively high in tuna, as they sit higher in the food chain. Tests conducted by the U.S. Food and Drug Administration show that Albacore "white" canned tuna has three times the mercury levels of that found in "light" tuna. Despite these findings, the FDA still refuses to warn women and children to limit canned tuna consumption like twelve states have already done. FDA"s new advice that it is safe for women and children to eat up to 12 ounces of seafood, including white tuna containing mercury levels over 0.3 parts per million, is placing millions at risk of mercury exposure according to Michael Bender of the Mercury Policy Project. This level of consumption would exceed the EPA's reference dose which is a health standard endorsed by the National Academy of Science. Canned tuna is one of the richest and most convenient sources of Omega-3. With benefits ranging from protective and preventive qualities on overall cardiac health and improved eye and skin health, the omega-3 acids found in tuna are an essential component of a balanced diet. Fortunately, omega-3's are abundant in most types of seafood but especially in cold-water varieties like tuna, one of the most omega-3 rich fish species. en.wikipedia.org & www.tunafacts.com Ref: US FDAExtract The distilled or evaporated oils of foods or plants (such as nuts, seeds, fruits, vegetables, herbs, spices, bark, buds, roots, leaves, meat, poultry, seafood, fish, dairy foods, or eggs) that are dissolved in an alcohol base or allowed to dry to be used as a flavoring. Food extracts as they are often labeled, are used to add a concentrated flavor to many food dishes, especially baked goods and desserts, without adding additional volume. Available in solid (cubes, granules or powdered), liquid or jelled form, extracts may be labeled as pure, natural or artificial. Pure and natural extracts are governed by laws in many countries that require compliance with procedures that take the extract ingredients directly from the named flavor, such as extracting oils directly from the vanilla bean to make pure or natural vanilla extract. Artificial extracts are flavors that do not necessarily use any ingredients directly from a source named for the extract but instead used combinations of ingredients to arrive at a flavor representative of the named food extract, such as artificial lemon extract. Some of the most widely used extracts include vanilla, almond, anise, maple, peppermint, and numerous solid or jelled extracts such as beef and chicken bouillon or meat demi-glaces. As an example of how the pure and natural extract is made, vanilla extract is created by soaking vanilla beans in water and an alcohol-based solution where it ages for several months, during which time the vanilla flavor is extracted from the bean. Anise extract, a sweet licorice tasting flavoring, is produced by dissolving the oil of anise seeds into alcohol. Grape extract is produced to assist with the wine making process. Compounds from the skin of grapes are extracted and added to the wine in order to impart tannin, color, and body into a wine. The characteristics of the wine can be changed dramatically by the amount of time the wine is in contact with the skins. If the grapes are in contact for too long, the resulting wine may be too potent, or what is sometimes called â€œover-extractedâ€�. Juices of fruits and vegetables are often extracted as juice extracts to be used similar to other food extracts, as a flavoring when preparing foods. A common utensil for the purpose of extracting lemon juice is available to assist with home recipes requiring a lemon flavoring.