White fruits and vegetables, like potatoes, bananas, garlic, and onions, are colored by the plant pigment anthoxanthin. Anthoxanthins are known for the healthy chemical allicin, which lowers cholesterol and blood pressure, as well as being anti-bacterial, anti-fungal and anti-viral, promoting overall health. Some members of this group are also high in potassium. Based in northern Virginia, Rebecca Rogge has been writing since She holds a bachelor's degree in journalism from Patrick Henry College and has experience in teaching, cleaning and home decor.
Her articles reflect expertise in legal topics and a focus on education and home management. Red Marine Algae Health Benefits. How to Change Eye Color Naturally. A medium tomato, for example, contains 16 milligrams, much less than one-half cup of broccoli, which has 51 milligrams, according to the Linus Pauling Institute. When looking to boost your iron levels, go for the green, says nutritionist Reed Mangels, author of "The Everything Vegan Pregnancy Book. Peas, collard greens and lima beans are also good sources.
Keep in mind that the iron in plants, called non-heme iron, is not as easily absorbed as that from animal sources; you may need to eat more iron-containing vegetables to obtain the same amount of iron as if you ate meat.
Blue and purple foods add interest to the color palate of your plate and also bring considerable nutritional value to the table. The blue compound that makes blueberries blue is a powerful antioxidant called anthocyanin that may protect against cancer and heart disease, according to the University of Maine Cooperative Extension.
A study published in the Romanian Journal of Diabetes Nutrition and Metabolic Diseases in linked purple eggplant flour with reduced oxidative stress in hyperglycemic rats. Oxidative stress is linked with a range of diseases, including heart disease, cancer and Parkinson's disease.
As you can see below, carotenoids have long carbon chains with circular structures on the ends. Exposure to oxygen can over time result in oxidation of the molecules, resulting in some loss of colour.
There are a lot of different carotenoids, one of the most well-known is beta-carotene, which can be transformed into vitamin A in the human body. There are a lot more though, for example: lycopene, xanthofyll, lutein and zeaxanthin.
Most plants contain a lot of carotenoids alongside the chlorophyll in the plant, it protects the chlorophyll and serves several other vital functions. However, normally, the chlorophyll will hide all these other colours. Only when the chlorophyll is broken down will these colours become visible. You might have seen this in broccoli that was in your fridge for a little too long. It is also the reason why tomatoes only turn red over time, and why underripe oranges still have some green.
The two main flavonoids that colour fruits and vegetables are anthocyanins and anthoxantins. Anthocyanins and anthoxantins have several phenol rings in their structures which helps them absorb light. There are hundreds of molecules that belong to these classes. The anthocyanins are known for their purple, blue and red colours.
Their colour is very sensitive to the acidity of its environment. This is why a vegetable like red cabbage can by both bright pink or dark blue, depending on what type of dressing acidic or not is on it.
Purple carrots are also a good example of anthocyanins in vegetables. Anthoxantins on the other hand are white and can be found in cauliflower and onions for instance. They are not as sensitive to pH. Betalains and betains both refer to the same group of molecules. They are most common in beets as well as a few other types of produce. Common betalains are betains these tend to be red and betaxanthines these tend to be yellow.
Betalains dissolve in water and are sensitive to heat, light and again pH. They are one of many ways to colour your food red. This is often unwanted discolouration and commonly caused by enzymatic browning. Physics classroom, To learn more about the basic physics of light, link.
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