OXYGEN RADICAL ABSORBANCE CAPACITY

It's a lab test that attempts to quantify the "total antioxidant capacity" (TAC) of a food by placing a sample of the food in a test tube, along with certain molecules that generate free radical activity and certain other molecules that are vulnerable to oxidation . After a while, they measure how well the sample protected the vulnerable molecules from oxidation by the free radicals. The less free radical damage there is, the higher the antioxidant capacity of the test substance.

Food ORAC scores - USDA

Food	Serving size	ORAC, Trolox equiv., μmol per 100 g
Prune	1 cup	14,582
Small Red Bean	½ cup dried beans	13,727
Wild blueberry	1 cup	13,427
Red kidney bean	½ cup dried beans	13,259
Pinto bean	½ cup	11,864
Cranberry	1 cup raw (whole berries)	9,584
Blueberry	1 cup raw (cultivated berries)	9,019
Artichoke hearts	1 cup, cooked	7,904
Raw unprocessed Cocoa bean	1 oz	7.840
Blackberry	1 cup raw (cultivated berries)	7,701
Raspberry	1 cup	6,058
Strawberry	1 cup	5,938
Red Delicious apple	1 apple	5,900
Granny Smith apple	1 apple	5,381
Pecan	1 oz	5,095
Sweet cherry	1 cup	4,873
Black plum	1 plum	4,844
Russet potato	1, cooked	4,649
Chokeberry	1 oz	4,497
Black bean	½ cup dried beans	4,181
Plum	1 plum	4,118
Gala apple	1 apple	3,903
Pomegranate	100 grams	2,860

 

This is a list of antioxidants naturally occurring in food. Vitamin C and vitamin E – which are ubiquitous among raw plant foods – are confirmed as dietary antioxidants, whereas vitamin A becomes an antioxidant following metabolism of provitamin A beta-carotene and cryptoxanthin. Most food compounds listed as antioxidants – such as polyphenols common in colorful, edible plants – have antioxidant activity only in vitro, as their fate in vivo is to be rapidly metabolized and excreted, and the in vivo properties of their metabolites remain poorly understood.

Vitamin A (retinol), also synthesized by the body from beta-carotene, protects dark green, yellow and orange vegetables and fruits from solar radiation damage, and is thought to play a similar role in the human body. Carrots, squash, broccoli, sweet potatoes, tomatoes (which gain their color from the compound lycopene), kale, mangoes, oranges, seabuckthorn berries, wolfberries (goji), collards, cantaloupe, peaches and apricots are particularly rich sources of beta-carotene, the major provitamin A carotenoid.

Vitamin C (ascorbic acid) is a water-soluble compound that fulfills several roles in living systems. Sources include citrus fruits (such as oranges, sweet lime, etc.), green peppers, broccoli, green leafy vegetables, black currants, strawberries, blueberries, seabuckthorn, raw cabbage and tomatoes.

Vitamin E, including tocotrienol and tocopherol, is fat soluble and protects lipids. Sources include wheat germ, seabuckthorn, nuts, seeds, whole grains, green leafy vegetables, kiwifruit, vegetable oil, and fish-liver oil. Alpha-tocopherol is the main form in which vitamin E is consumed. Recent studies showed that some tocotrienol isomers have significant anti-oxidant properties.

 

Carotenoid

• Alpha-carotene - found in carrots, winter squash, tomatoes, green beans, cilantro, Swiss chard
• Astaxanthin - found naturally in red algae and animals higher in the marine food chain. It is a red pigment familiarly recognized in crustacean shells and salmon flesh/roe.
• Beta-carotene - found in high concentrations in butternut squash, carrots, orange bell peppers, pumpkins, kale, peaches, apricots, mango, turnip greens, broccoli, spinach, and sweet potatoes.
• Canthaxanthin
• Cryptoxanthin - present in papaya, egg yolk, butter, apples
• Lutein - found in high concentration in spinach, kale, Swiss chard, collard greens, beet and mustard greens, endive, red pepper and okra
• Lycopene - found in high concentration in cooked red tomato products like canned tomatoes, tomato sauce, tomato juice and garden cocktails, guava and watermelons.
• Zeaxanthin - best sources are kale, collard greens, spinach, turnip greens, Swiss chard, mustard and beet greens, corn, and broccoli

 

Many common foods contain rich sources of polyphenols which have antioxidant properties only in test tube studies. As interpreted by the Linus Pauling Institute, dietary polyphenols have little or no direct antioxidant food value following digestion.Not like controlled test tube conditions, the fate of flavones or polyphenols in vivo shows they are poorly absorbed and poorly conserved (less than 5%), so that most of what is absorbed exists as metabolites modified during digestion, destined for rapid excretion.

Spices, herbs, and essential oils are rich in polyphenols in the plant itself and shown with antioxidant potential in vitro. Typical spices high in polyphenols (confirmed in vitro) are clove, cinnamon, oregano, turmeric, cumin, parsley, basil, curry powder, mustard seed, ginger, pepper, chili powder, paprika, garlic, coriander, onion and cardamom. Typical herbs are sage, thyme, marjoram, tarragon, peppermint, oregano, savory, basil and dill weed.

Dried fruits are a good source of polyphenols by weight/serving size as the water has been removed making the ratio of polyphenols higher. Typical dried fruits are pears, apples, plums, peaches, raisins, figs and dates. Dried raisins are high in polyphenol count. Red wine is high in total polyphenol count which supplies antioxidant quality which is unlikely to be conserved following digestion (see section below).

Deeply pigmented fruits like cranberries, blueberries, plums, blackberries, raspberries, strawberries, blackcurrants, figs, cherries, guava, oranges, mango, grape juice and pomegranate juice also have significant polyphenol content.

Typical cooked vegetables rich in antioxidants are artichokes, cabbage, broccoli, asparagus, avocados, beetroot and spinach.

Nuts are a moderate source of polyphenol antioxidants. Typical nuts are pecans, walnuts, hazelnuts, pistachio, almonds, cashew nuts, macadamia nuts and peanut butter.

Sorghum bran, cocoa powder, and cinnamon are rich sources of procyanidins, which are large molecular weight compounds found in many fruits and some vegetables. Partly due to the large molecular weight (size) of these compounds, their amount actually absorbed in the body is low, an effect also resulting from the action of stomach acids, enzymes and bacteria in the gastrointestinal tract where smaller derivatives are metabolized and prepared for rapid excretion.