Raspberries
Fragrantly sweet with a subtly tart overtone and almost-melt-in-your-mouth texture, raspberries are wonderfully delicious and are usually in limited supply. Most cultivated varieties of raspberries are grown in California from June through October.
A member of the rose family and a bramble fruit like the blackberry, raspberries are delicately structured with a hollow core. Raspberries are known as "aggregate fruits" since they are a compendium of smaller seed-containing fruits, called drupelets, that are arranged around a hollow central cavity.
- Health Benefits
- Description
- History
- How to Select and Store
- How to Enjoy
- Safety
- Nutritional Profile
- References
Red raspberry is most often the source of a dietary supplement sold in many health food stores called ellagic acid. This substance found naturally in raspberries belongs to the family of phytonutrients called tannins, and it is viewed as being responsible for a good portion of the antioxidant activity of this (and other) berries.
Phytonutrients for Antioxidant, Antimicrobial and Anticarcinogenic Protection
As an antioxidant food containing ellagic acid, raspberries help prevent unwanted damage to cell membranes and other structures in the body by neutralizing free radicals. Ellagic acid is not the only well-researched phytonutrient component of raspberry, however. Raspberry's flavonoid content is also well documented. Here the key substances are quercetin, kaempferol, and the cyanidin-based molecules called cyanidin-3-glucosylrutinoside and cyanidin-3-rutinoside. These flavonoid molecules are also classified as anthocyanins, and they belong to the group of substances that give raspberries their rich red color. Raspberries' anthocyanins also give these delectable berries unique antioxidant properties, as well as some antimicrobial ones, including the ability to prevent overgrowth of certain bacteria and fungi in the body (for example, the yeast Candida albicans, which is a frequent culprit in vaginal infections and can be a contributing cause in irritable bowel syndrome).
Additionally, research is suggesting that raspberries may have cancer protective properties. Research with animals has suggested that raspberries have have the potential to inhibit cancer cell proliferation and tumor formation in various parts of the body, including the colon. Antioxidants Unique to Raspberries Provide Powerful Protection Raspberries possess almost 50% higher antioxidant activity than strawberries, three times that of kiwis, and ten times the antioxidant activity of tomatoes, shows research conducted in the Netherlands and published in the journal BioFactors. The biggest contribution to raspberries' antioxidant capacity is their ellagitannins, a family of compounds almost exclusive to the raspberry, which are reported to have anti-cancer activity. Vitamin C contributes about 20% of the total antioxidant capacity, accounting for up to 30 milligrams in 100 grams (3.5 ounces) of fruit. Raspberries anthocyanins, especially cyanidin and pelagonidin glycosides, make up another 25%. And more good news: freezing and storing raspberries does not significantly affect their antioxidant activity, although in this study, their concentration of vitamin C was halved by the freezing process.
Plus Vitamin and Mineral Antioxidants
In addition to their unique phytonutrient content, raspberries are filled with traditional nutrients, primarily in the antioxidant and B vitamin categories. Raspberries emerged from our nutrient ranking system as an excellent source of manganese and vitamin C, two critical antioxidant nutrients that help protect the body's tissue from oxygen-related damage. They also qualified as a good source of riboflavin, folate, niacin, magnesium, potassium and copper. Coupled with this strong B vitamin and mineral content, raspberries qualified as "excellent" in terms of dietary fiber. This combination of nutrients makes raspberries a great fruit choice for having minimal impact on blood sugars. Promote Optimal Health Protection against Macular Degeneration Your mother may have told you carrots would keep your eyes bright as a child, but as an adult, it looks like fruit is even more important for keeping your sight. Data reported in a study published in the Archives of Ophthalmology indicates that eating 3 or more servings of fruit per day may lower your risk of age-related macular degeneration (ARMD), the primary cause of vision loss in older adults, by 36%, compared to persons who consume less than 1.5 servings of fruit daily. In this study, which involved over 110,000 women and men, researchers evaluated the effect of study participants' consumption of fruits; vegetables; the antioxidant vitamins A, C, and E; and carotenoids on the development of early ARMD or neovascular ARMD, a more severe form of the illness associated with vision loss. While, surprisingly, intakes of vegetables, antioxidant vitamins and carotenoids were not strongly related to incidence of either form of ARMD, fruit intake was definitely protective against the severe form of this vision-destroying disease. Three servings of fruit may sound like a lot to eat each day, but raspberries can help you reach this goal. Top your morning cereal or lunch time yogurt or cottage cheese with fresh raspberries. Transform the taste and presentation of any green salad with a handful of raspberries and a splash of balsamic vinegar. Blend frozen raspberries with a spoonful of honey and some vanilla soy milk, freeze for 20 minutes, then spoon into serving cups and decorate with a sprig of mint for an elegant, healthy treat.
Raspberries are known as "aggregate fruits" since they are a compendium of smaller seed-containing fruits, called drupelets, which are arranged around a hollow central cavity. Their shape conveys to them a very delicate, almost "melt-in-your-mouth" texture. They are fragrantly sweet with a subtly tart overtone. While the most common type of raspberry (Rubus idaeus) is red-pink in color, raspberries actually come in a range of colors including black, purple, orange, yellow and white. Both loganberries and boysenberries are hybrids of raspberries.
Raspberries can trace a long history dating back to prehistoric times. While wild raspberries are thought to have originated in eastern Asia, there are also varieties that are native to the Western Hemisphere. The seeds of these raspberries were likely to have been carried by travelers or animals that came across the Bering Straight during ancient times.
The spread of wild raspberries through the world seems to have occurred via similar means. The early hunter-gatherers traveled to far distances to collect food. On their treks back to the villages they would discard what they considered to be inferior quality foods, including the smaller sized raspberries. Thus began the propagation of these plants in other areas.
There seems to be no evidence that raspberries were cultivated until this millennia, with the first written mention being found in an English book on herbal medicine dated 1548. Raspberries began to be grown more widely in Europe and North America in the 19th century when many new varieties such as the loganberry and boysenberry were developed through either accidental or intentional crossbreeding. Currently, the leading commercial producers of raspberries include Russia, Poland, Yugoslavia, Germany, Chile and the United States.
As raspberries are highly perishable, they should only be purchased one or two days prior to use. Choose berries that are firm, plump and deep in color, while avoiding those that are soft, mushy or moldy. If you are buying berries prepackaged in a container, make sure that they are not packed too tightly, since this may cause them to become crushed and damaged, and that the container has no signs of stains or moisture, indication of possible spoilage. Raspberries are generally available from midsummer through early fall.
Raspberries are one of the most perishable fruits, so extreme care should be taken in their storage. Before storing in the refrigerator, remove any berries that are molded or spoiled so that they will not contaminate the others. Place the unwashed berries back in their original container or spread them out on a plate lined with a paper towel, then cover the plate with plastic wrap. Raspberries will keep fresh in the refrigerator for one or two days. Make sure not to leave raspberries at room temperature or exposed to sunlight for too long, as this will cause them to spoil.
Raspberries freeze very well. Wash them gently using the low pressure of the sink sprayer so that they will maintain their delicate shape and then pat dry with a paper towel. Arrange them in a single layer on a flat pan or cookie sheet and place them in the freezer. Once frozen, transfer the berries to a heavy plastic bag and return them to the freezer where they will keep for up to one year. Adding a bit of lemon juice to the raspberries will help to preserve their color.
Baby foods containing berries are bereft of anthocyanins, the water-soluble plant pigments responsible not only for the blue, purple, and red color of berries, but also for many of their health benefits.
Anthocyanins are found in fresh and frozen berries, but not in processed foods.
A study published in the Journal of Agricultural and Food Chemistry found anthocyanins were almost undetectable in canned foods, bread, cereals, and baby foods containing berries, even in baby foods prepared from fruits high in anthocyanins, such as blueberries.
This may be due to anthocyanins' unique chemical structure, which renders them unstable even at a neutral pH and therefore much more susceptible to destruction during processing than other phytonutrients, such as proanthocyanidins. To give your children the full health benefits of berries, purchase fresh or frozen berries and purée them.
For some of our favorite recipes, click Recipes.
Tips for Preparing Raspberries:
As raspberries are very delicate, wash them very gently, using the light pressure of the sink sprayer if possible, and then patting them dry. They should be washed right before eating or recipe preparation so that they do not become water-soaked and are not left at room temperature for too long. Do not use any berries that are overly soft and mushy unless you will be puréeing them for a sauce or coulis.
A Few Quick Serving Ideas:
Mix fresh raspberries in with creamy millet porridge for a sweet morning breakfast treat.
While at first glance it may seem unusual, the flavor combination created by sprinkling fresh raspberries with balsamic vinegar will send your palate to heaven.
Plain yogurt mixed with raspberries, honey and freshly ground mint is delicious eaten as is or used as a topping for waffles or pancakes.
Almond butter and raspberry jam are a flavorful alternative to the traditional PB&J sandwich.
Depending upon how much sweetener you use, homemade raspberry coulis can be used as a sauce for either savory poultry dishes or sweet desserts.
Raspberries and Oxalates
Raspberries are among a small number of foods that contain measurable amounts of oxalates, naturally-occurring substances found in plants, animals, and human beings. When oxalates become too concentrated in body fluids, they can crystallize and cause health problems. For this reason, individuals with already existing and untreated kidney or gallbladder problems may want to avoid eating raspberries. Laboratory studies have shown that oxalates may also interfere with absorption of calcium from the body. Yet, in every peer-reviewed research study we've seen, the ability of oxalates to lower calcium absorption is relatively small and definitely does not outweigh the ability of oxalate-containing foods to contribute calcium to the meal plan. If your digestive tract is healthy, and you do a good job of chewing and relaxing while you enjoy your meals, you will get significant benefits-including absorption of calcium-from calcium-rich foods plant foods that also contain oxalic acid. Ordinarily, a healthcare practitioner would not discourage a person focused on ensuring that they are meeting their calcium requirements from eating these nutrient-rich foods because of their oxalate content. For more on this subject, please see "Can you tell me what oxalates are and in which foods they can be found?"
Raspberries are an excellent source of fiber, manganese and vitamin C. They are a good source of vitamin B2, folate, niacin, magnesium, potassium and copper. In addition, they contain significant amounts of the anti-cancer phytochemical ellagic acid.
For an in-depth nutritional profile click here: Raspberries.
In-Depth Nutritional Profile
In addition to the nutrients highlighted in our ratings chart, an in-depth nutritional profile for Raspberries is also available. This profile includes information on a full array of nutrients, including carbohydrates, sugar, soluble and insoluble fiber, sodium, vitamins, minerals, fatty acids, amino acids and more.Introduction to Food Rating System Chart
The following chart shows the nutrients for which this food is either an excellent, very good or good source. Next to the nutrient name you will find the following information: the amount of the nutrient that is included in the noted serving of this food; the %Daily Value (DV) that that amount represents; the nutrient density rating; and the food's World's Healthiest Foods Rating. Underneath the chart is a table that summarizes how the ratings were devised. Read detailed information on our Food and Recipe Rating System.
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