Purple raspberries (scientific name: Rubus neglectus) are a cross between red and black raspberries. The species is both cultivated and found occurring naturally in the wild. Purple raspberries owe their rich plum tones to anthocyanins, a class of pigmented antioxidants with free radical-scavenging properties, anti-inflammatory and antimicrobial activity. The plum-colored berries also provide good amounts of vitamins C and E, dietary minerals such as copper, iron, manganese and potassium, are low in calories and a great source of dietary fiber.
What are purple raspberries? They are a hybrid species of the fruit obtained as a result of the crossing of black and red raspberry plants. They are known to occur naturally if two red and black raspberry plants are in close proximity to one another, allowing for hybridization. The most commercially important species is Rubus neglectus. Some cultivars are sometimes commonly referred to as ‘blue raspberry’, a name suggestive of the stronger bluish tones in some fruits. Purple raspberry plants are available for sale in nurseries and popular cultivars include Brandywine, Royalty, Glencoe. Planting, growing and pruning this spectacularly-colored berry isn’t any different from caring for other Rubus species.
What do purple raspberries look like? The fruits start off light green in color and gradually ripen to a deep reddish-purple or plum color. At their ripest, purple raspberries may have either more pronounced reddish tones or tones of blue, depending on the cultivar. The ripe fruits come off the stalk extremely easy. Picking leaves a hollow in the fruit as the little stem and the core attached to it stay on the plant. At this point, the raspberry looks like a little empty, purplish basket. Purple and other raspberries are not real berries, but rather aggregate fruits meaning dozens of individual fruits clump together to form what we commonly call a ‘raspberry’. Each individual fruit contains a tiny edible seed.
What do purple raspberries taste like? Purple raspberry taste can be described as fresh with sweet, flavorful fruity notes and moderate astringency. The berries are sweeter than those of red varieties. The riper the fruit, the more pronounced the sweetness and the lower the acidity. Unripe (aka green) purple raspberries will be tough. Not fully ripe fruits may be sour, astringent or tangy to the taste. Overall, purple raspberries have a pleasant flavor reminiscent of both the black and red parent species.
Purple raspberries vs red raspberries
What is the difference? First of all, purple raspberries are a cross resulting from the hybridization of red and black raspberry species. Other than this, the two varieties of the fruit are quite similar. In addition to a fairly similar nutritional profile, both get their color from pigmented anthocyanin antioxidants. Anthocyanins are essentially pigments in plants that give leaves, flowers and fruits their red, blue, purple or black colors. In red raspberries, they yield deep red colors, whereas in purple ones, they yield purple or plum colors.
The nutritional profile of purple raspberries specifically is poorly researched, but the fruit is considered to hold a fairly similar nutritional value as its red and black color variants. What this means is that purple raspberries are expected to be a good source of vitamin C, vitamin E and vitamin K, but also antioxidant minerals such as copper, manganese and iron. Limited amounts of other essential vitamins and minerals, including B vitamins, vitamin A and other dietary minerals such as calcium, magnesium, potassium and zinc, are also typically present in all color variants of the fruit.
The ripe berries are an excellent source of dietary fiber, have a high water content, but low energetic value (roughly 50 kcal per 100 g), around 1 g of protein (per 100 g) and almost no fat. With regards to its antioxidant content, Rubus neglectus is more similar to its darker-colored parent, the black raspberry. It is an important source of pigmented anthocyanin antioxidants with therapeutic potential. Other polyphenols include ellagic acid, ellagitannins, catechins, kaempferol, gallic acid etc. Also see the benefits of black raspberries.
What are the benefits?
The health benefits of purple raspberries are roughly the same as the health benefits of its parents and may include:
1) Constipation relief and other benefits for digestion thanks to a good fiber content.
2) Good food for hemorrhoids as a result of fiber content (fiber promotes regular bowel movements).
3) Satiating, supports healthy weight loss: in addition to dietary fiber being filling and curbing hunger, the low calorie and fat content further help maintain a steady weight.
4) The berries help correct hypoglycemia (low blood sugar levels), but don’t raise blood sugar excessively thanks to a generous fiber content.
5) The vitamin E in purple raspberry seeds holds antioxidant and anti-aging benefits for skin as well as nourishes skin and helps it better retain moisture for a more youthful appearance.
6) Anti-inflammatory food thanks to vitamins C, E, K, dietary minerals and anthocyanin antioxidants.
7) Good food for more energy: carbs and sugar provide quick energy to use, while iron and B vitamins have a revitalizing effect and combat muscle weakness and fatigue.
8) Cholesterol-lowering benefits as a result of dietary fiber, vitamin E and anthocyanin antioxidants.
9) Blood pressure-lowering benefits from magnesium, potassium and anthocyanin antioxidants.
10) Anticancer properties: in vitro studies show anthocyanin antioxidants inhibit proliferation of various cancer cell lines and have anti-mutagenic effects, preventing cell damage.
11) Vitamin C in purple raspberries supports the production of collagen which maintains blood vessel elasticity.
12) Anthocyanin antioxidants have been shown to support endothelial function for reduced risks of cardiovascular disease.