Orange peels, generally considered as waste, were treated with subcritical water (SWE)—a green technology and environmentally friendly extraction process—at different temperatures (120–200 °C) and extraction times (5–60 min). The extracts which were obtained were chemically and biologically characterised to evaluate this potential source of bioactive compounds. The extracts total phenolics content (TPC) and total flavonoids contents (TFC), as well as total antioxidant capacity (TAC), DPPH radical scavenging activity, and total carbohydrate content, were determined by UV spectrophotometry. The pectin content was quantified by a gravimetric method. The dietary fibre content was investigated, and a phytochemical screening assay was performed. The extract obtained at 120 °C for 5 min displayed the highest TPC (45.45 mg GAE/g DW), TFC (9.29 mg RE/g DW), and TAC (130.47 mg AAE/g DW), indicating that relatively low temperatures and extremely short extraction times can be used in SWE to obtain orange peel extracts that are rich in bioactive compounds. The results of this study demonstrate the exceptional potential of orange peel extracts obtained with SWE. As shown, this biowaste represents a promising source of health-promoting compounds that could be used in pharmaceutical and dietary products.

The functional properties of food products, in addition to enrichment with functional components, can also be achieved by reducing the content of certain components such as sugars and fats, that is, by reducing the energy content of the product. Thus, the development of functional food products is aimed at various low-energy products, especially products with a reduced fat content, which normally represent the most concentrated source of energy. Fat replacers should simulate the functional properties of the fat. Polysaccharide-based fat replacers include a variety of native starches, modified starches, maltodextrins, cellulose and cellulose derivatives, polydextrose, inulin, pectin, other dietary fibers, and hydrocolloids. Technological properties required for the application of carbohydrate-based fat replacers are water-holding capacity, a certain level of viscosity, required form and particle size, three-dimensional networking and gel-forming ability, sensory abilities such as spreadability, softness, greasiness feeling in the mouth, and other fat-like properties. These fat replacers are usually applied in combinations with the aim of achieving all desired properties normally provided by fats in foods. In the contemporary literature, there are many examples of their application in different food products, including baked goods, meats, dairy products, and emulsion food systems, successfully reducing the fat content with or without minor alterations in the rheology or sensory features of food products. In summary, polysaccharides-based fat replacers offer an effective method for fat reduction in different food products along with enhancing the health benefits of reduced-fat foods.

Oilseed crops are widely cultivated and are related to nutrition and human health as valuable nutraceutical sources with valuable biological properties. The growing demand for oil plants used in human and animal nutrition or for the processing industry has contributed to the diversification and development of a new variety of oil crops. Increased oil crop diversity, besides ensuring reduced sensitivity to pests and climate conditions, has also led to improved nutritional values. In order to enable oil crop cultivation to become commercially sustainable, a comprehensive characterization of newly created varieties of oilseeds, including their nutritional and chemical composition, is required. In this study, two varieties of safflower and white and black mustard were investigated as alternative oil species for nutritional parameters, mainly protein, fat, carbohydrate, moisture, ash, polyphenols, flavonoids, chlorophylls contents, acids and mineral composition, and compared with those of two different genotypes of rapeseeds as a traditional oil crop plant. The proximate analysis found that the highest oil content was found in the oil rape NS Svetlana genotype (33.23%), while the lowest was in black mustard (25.37%). The protein content varies from around 26% in safflower samples to 34.63%, determined in white mustard. High content of unsaturated fatty acids and low content of saturated fatty acid was observed in the analyzed samples. In mineral analysis, the dominant elements were phosphorus, potassium, calcium and magnesium, in descending order. The observed oil crops are also good sources of microelements, including iron, copper, manganese and zinc, accompanied by high antioxidant activity due to the presence of significant amounts of polyphenolic and flavonoid compounds.

Resistant starch (RS) is a part of insoluble dietary fiber, and it could be recognized as a functional food ingredient in some types of confectionery products that lack dietary fiber. Unlike dark and milk chocolate, white chocolate does not contain fat-free cocoa solids rich in dietary fiber. In the present study, 5%, 10%, and 15% of white chocolate were substituted with RS in order to improve the nutritional value of enriched white chocolate. The influence of RS on rheological, textural, and thermal properties of the chocolate fat phase was firstly investigated, and then further influence on physical properties, dietary fiber content, and sensory characteristics of enriched white chocolates were investigated. The obtained results showed that enriched chocolates had increased content of total dietary fiber and reduced total fats and protein content in accordance with the added amount of RS. At the same time, RS increased viscosity and reduced the hardness and volume mean diameter in enriched chocolates in accordance with the added amount. RS improved the nutritional composition of white chocolate by increasing the content of dietary fiber. At the same time, RS did not impair the color and sensory characteristics of enriched white chocolates.