Apples are a crisp, white-fleshed fruit with a red, yellow or green skin. The apple is actually a member of the Rose family, which may seem strange until we remember that roses make rose hips, which are fruits similar to the apple.
Apples have a moderately sweet, refreshing flavor and a tartness that is present to greater or lesser degree depending on the variety. For example, Golden and Red Delicious apples are mild and sweet, while Pippins and Granny Smith apples are notably brisk and tart. Tart apples, which best retain their texture during cooking, are often preferred for cooked desserts like apple pie, while Delicious apples and other sweeter varieties like Braeburn and Fuji apples are usually eaten raw.
Look for firm fruits with rich coloring. Yellow and green apples with a slight blush are best. Your preference for a sweeter or more tart fruit and whether you plan to enjoy your apples raw or cooked will guide your choice of variety. Just remember that Red and Golden Delicious are among the sweetest apples. Braeburn and Fuji apples are slightly tart, and Gravenstein, Pippin, and Granny Smith apples are the most tart, but retain their texture best during cooking.
Whole apples are a much better nutritional choice than apple juice. Not only are whole apples richer in dietary fiber, but the current processes of juicing seem to drastically reduce the polyphenolic phytonutrient concentrations originally found in the whole fruit.
Apples can be stored for relatively long (3-4 months) periods of time. Cold storage at low refrigerator temperatures (35-40F/2-4C) is able to help minimize loss of nutrients. In addition, it’s helpful to maintain some moisture in the cold storage area, for example, by inclusion of damp cheesecloth in the crisper bin of a refrigerator. Over a period of time involving months, there is loss of total polyphenols from apples, including both flavonoid and non-flavonoid polyphenols. However, valuable amounts of polyphenols (and all other nutrients) remain. In some food traditions, cold storage of apples over the winter months is still counted on as a key part of dietary nourishment from fruits.
The skin of the apple is unusually rich in nutrients, and even if the recipe you’ve chosen requires peeled apples, consider leaving the skins on to receive the unique benefits found in the skins. Just be sure to thoroughly rinse the entire apple under a stream of pure water while gently scrubbing the skin with a natural bristle brush for 10-15 seconds.
To prevent browning when slicing apples for a recipe, simply put the slices in a bowl of cold water to which a spoonful of lemon juice has been added. For use in future recipes, sliced apples freeze well in plastic bags or containers.
Apple polyphenols are standout nutrients in this widely loved fruit. These polyphenols include flavonols (especially quercetin, but also kaempferol and myricetin), catechins (especially epicatechin), anthocyanins (if the apples are red-skinned), chlorogenic acid, phloridizin, and several dozen more health-supportive polyphenol nutrients. Apple is a good source of fiber, including the soluble fiber pectin, and it’s also a good source of vitamin C. Apple nutrients are disproportionately present in the skin, which is a particularly valuable part of the fruit with respect to its nutrient content.
Source: World’s Healthiest Foods