The black chokeberries

To the most important polyphenols of black chokeberries belong phenolic acids and flavonoids such as anthocyanins, flavanols, flavonols and proanthocyanidins 43 As the most significant phenolic compounds were identified from the group of phenolic acids hydroxycinnamic acids, especially neochlorogenic acid, from anthocyanins, there were cyanidin-3-galactoside and cyanidin-3-arabinoside; from proanthocyanidins, procyanidin B1. Flavanols (epicatechin) and flavonols (mainly quercetin glycosides) are minor components of black chokeberry fruits 43 , 48. The total polyphenols (TP) in A. melanocarpa berries were quantified as higher than for many other remarkable berries, including blueberries, red raspberries, red currant, strawberries and blackberries 44 , 46 , 48 The comparison of TP content in various important fruit berries confirms that the amount of TP in A. melanocarpa berries is similar to black currant (Ribes nigrum) content, about 2-4-fold of the content in blackberry (Rubus fruticosus), 4-fold for blueberry (Vaccinium corymbosum), 3-8-fold for red raspberry (Rubus idaeus) and 10-times more than in strawberry (Fragaria ananassa). In recent history, black chokeberry has been extensively produced in Russia as a small fruit, used in juice products (mixed with apple juice), wine, compote and pickles ( Kask ). It has been commercially grown in Europe where its fruits are used in juice, alcoholic beverages, energizing beverages, and as a food colorant ( Bussieres et al. ). Sweden initiated studies to develop this crop in 1986 ( Jeppsson and Johansson ). Knudson notes that fruits can be canned whole, the juice can be used in fruit drinks and jelly, and extracts can be used as natural colorants in the food industry.

The use of black chokeberry fruits as a source of food colorants has spurred recent research. Aronia melanocarpa (black chokeberry) has attracted scientific interest due to its deep purple, almost black pigmentation that arises from dense contents of polyphenols , especially anthocyanins Total polyphenol content is 1752 mg per 100 g dry weight, 22 anthocyanin content is 1480 mg per 100 g dry weight, and proanthocyanidin concentration is 664 mg per 100 g fresh weight. For more information, see: Antioxidant Activity and Polyphenols of Aronia in Comparison to Other Berry Species, a study of antioxidant compounds found in aronia and other berries (Jakobek et al. 2007).

The small dark berries of the Aronia melanocarpa plant are packed with nutrients and antioxidants, such as vitamin C and anthocyanins, in some countries, dried Aronia berries are used to make antioxidant-rich herbal tea. USDA research shows Aronia berries has one of the highest antioxidant content of any fruits. However, in a study by Frejnagel and Juskiewicz 40 differences in weights of the cecal contents were not observed with a chokeberry extract, but when an extract of polyphenols from green tea was fed, an increase in cecal content weight was observed 40 In another study, feeding the polyphenol extract from chokeberries altered cecal parameters and metabolism as shown by a reduction in cecal digesta pH and ammonia concentrations in comparison to control animals 40 In a previous study by Heyman and Axling 25 in which diets were supplemented with one of 8 different berries the mass of the cecum, including its contents, was increased in all berry supplemented groups compared to the control diet with the exception of the raspberry supplemented group 25 Our data support these findings, which could be due a change in microbial fermentative activity in the cecum 41 , however further research is needed to determine the mechanisms of action.