## 1 Introduction  
Bread is one of the basic food products consumed widely in many regions of the world. In Europe, wheat bread is particularly popular, most often produced from low-extraction white flour. The advantages of such bread are a crunchy crust, soft, fluffy, and light-colored crumbs, and easy digestibility [1]. However, white wheat bread is characterized by a relatively low nutritional value, containing a high amount of carbohydrates and little dietary fiber, mineral components, vitamins, or other bioactive compounds, regular consumption of which is an essential element of preventive healthcare [2, 3]. In recent years, a popular trend has been to enrich the recipe of food with additional ingredients to obtain a product with functional properties [4]. Bread, due to its frequent consumption, provides a good food matrix for introducing various recipe additives, such as oily plant seeds [5], flour from other types of grains or pseudocreals [6; 7; 8], flour from legume seeds [9; 10], spices, herbs [11; 12; 13; 14], and dried vegetable and fruit extracts [15; 16], as well as waste products from the processing of plant raw materials, such as bran, brewer's spent grain, or pomace [17; 18; 19]. It should be emphasized that waste products can be particularly valuable recipe ingredients for bread, as they are often characterized by a much higher content of valuable nutritional components than the raw materials from which they were processed [20]. The use of waste products is in line with the EU's policy on waste-free food production and is one of the elements of the circular economy strategy [21]. A plant with exceptional chemical composition of its fruit is the black chokeberry (_Aronia melanocarpa_ (Michx.) [PERSON]), a perennial deciduous shrub from the _Rosenaceae_ family. This plant comes from North America and is characterized by low soil requirements and high frost and disease resistance, and is currently widely cultivated in the northern and eastern parts of Europe. Aronia fruits are spherical in shape and are gathered in clusters. When ripe, they have a dark pomeranate to black color, are covered with a waxy coating, and are slightly shiny [22]. The dry matter content in aronia fruits is 17.9-26.0% [22; 23], including 13.7-15.1% carbohydrates, 4.8-6.3% dietary fiber, 0.7% protein, and 0.2% fat [24]. Aronia fruits are characterized by an exceptionally high content of active substances that have a beneficial effect on the body, which is why they are called a superfruit or superberry [23]. These compounds include polyphenols, including anthocyanins, flavonoids, tannins, and phenolic acids. The total content of polyphenols in aronia fruits is 2000-8000 mg per 100 g of dry matter, including about 500 mg of anthocyanins [22; 25]. The most important compounds from the group of anthocyanins are cyanidin glycosides (3-O-galactoside, 3-O-arabinoside, 3-O-xyloside, and 3-O-glucoside) [25]. Aronia fruits are also rich in phenolic acids, mainly chlorogenic and neochlorogenic acid [23]. They also contain flavonoid glycosides, with quercetin 3-O-galactoside and quercetin 3-O-glucose being the most prevalent. Tannins are also included in the phenolic compounds, with a content of approximately 0.4% [22]. Together with organic acids, they contribute to the tart taste of the fruits. In addition, aronia fruits are a source of vitamins, especially vitamin C, as well as vitamins E, K, B1, B2, B3, B5, B6, and folic acid [24], and macro- and microelements, including magnesium, potassium, calcium, iron, iodine, molybdenum, and manganese [26; 27; 24]. Ripe aronia berries are characterized by a tart and bitter taste, and therefore are rarely consumed in their unprocessed form as a dessert fruit. They are widely used in processing as a raw material for the production of juices, jams, preserves, beverages, wines, liqueurs, and infusions, as well as fruit teas and jellies, and for obtaining food extracts and dyes [23; 28]. During the processing of the berries, waste is produced in the form of pomace. [PERSON] et al.