The aim of the present study was to increase the value of rice protein concentrate (RPC) by improving the functional properties of a preparation subjected to acetylation and analyze the impact of this chemical modification on chemical composition, digestibility, and protein patterning using SDS-PAGE electrophoresis and FT-IR spectroscopy. In the modified samples, the protein content increased (80.90–83.10 g/100 g cf. 74.20 g/100 g in the control). Electrophoresis revealed that the content of the main rice protein fractions (prolamin and glutelin) decreased as the concentration of the modifying reagent increased. Through spectroscopic analysis, wavenumbers, corresponding to the presence of proteins or lipids, aromatic systems, and carbohydrates, were observed. The use of acetic anhydride did not change the digestibility of the modified RPC significantly when compared to that of the control sample. The acetylation of the RPC caused a significant increase in its emulsifying properties at pH 8 (1.83–14.74%) and its water-binding capacity but did not have a statistically significant impact on the oil-absorption capacity. There was a slight increase in protein solubility and a decrease in foaming capacity in the modified RPC.

Glycoalkaloids (TGAs, total glycoalkaloids), toxic secondary metabolites, are found in potatoes (110–335 mg·kg⁻¹ DW), mainly in the peel. Colorful, unpeeled potatoes are an innovative raw material for the production of snacks which are poorly tested in terms of their glycoalkaloid content. Third-generation snacks and French fries made from red-fleshed Mulberry Beauty (MB) and purple-fleshed Double Fun (DF) potatoes were produced with the use of 1% solutions of ascorbic, citric, lactic, malic, and tartaric acids to stabilize the structure of anthocyanins in the raw material and maintain their color in obtained products. The influence of the type of acid and thermal processes, like frying, microwaving, and baking, on the content of glycoalkaloids in ready-made products was examined. Only 0.45–1.26 mg·100 g⁻¹ of TGA was found in pellet snacks and 1.32–1.71 mg·100 g⁻¹ in French fries. Soaking blanched potatoes in organic acid solution reduced the α-chaconine content by 91–97% in snacks and by 57–93% in French fries in relation to the raw material to the greatest extent after the use of malic acid and the DF variety. The effect of lactic and citric acid was also beneficial, especially in the production of baked French fries from MB potatoes.

This study analyzed the chemical, functional, and bioactive properties of a protein preparation obtained from bird cherry (Prunus padus L.) flour. The extraction process significantly increased the protein content from 15.44 g/100 g to 39.72 g/100 g and altered the lipid composition, with an increase in saturated and polyunsaturated fatty acids. The protein preparation exhibited high solubility (76%) and water-binding capacity, demonstrating technological potential for use in the production of plant-based beverages and emulsions. Changes in color and emulsifying properties indicated its suitability for incorporation into colored food products. The analysis of total phenolic content, antioxidant activity, and amygdalin showed that the extraction process largely retained these bioactive properties, although individual phenolic compounds were not profiled. This study is the first to provide a comprehensive characterization of the protein fraction from Prunus padus L. flour, encompassing chemical, functional, and bioactive properties, thereby filling a significant gap in the literature. In summary, bird cherry flour is an attractive source of natural proteins and bioactive compounds, with potential applications in the food industry, while maintaining a favorable nutritional and functional profile. To date, no comprehensive chemical, functional, and bioactive characterization of the protein fraction from Prunus padus L. flour has been reported.