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(1) Background: In this study, bioactive compounds (phenolics and betalains) extracted from beetroot were stabilized by encapsulation with maltodextrin and soy protein by the freeze drying method. Stability of bioactive compounds and bioactivities in a beetroot extract and encapsulates during 60 days of storage at 4 °C (without light) and at 25 °C (with and without light) were investigated. (2) Methods: Contents of bioactive compounds and bioactivity (antioxidant activity by DPPH, RP, and ABTS tests; anti-inflammatory and antihyperglycemic activity) were determined. Improvement in stability of bioactives' content and bioactivity of prepared encapsulates in relation to the extract was observed after storage at room temperature under light conditions. (3) Results: Encapsulation with maltodextrin showed improvement in stability of all studied bioactive parameters, while an encapsulate with soy protein improved stability of bioactives and antioxidant activity compared to the extract. The encapsulated beetroot extract represents a promising food additive for functional foods due to their content of bioactive compounds and consequent bioactivities. [ABSTRACT FROM AUTHOR]

Grape (Vitis vinifera) as one of the world's largest fruit crops. Grape skin is a source of large amounts of phenolic compounds which can act as antioxidants. Rosehip (Rosa canina L.) is among the most popular and widely used herbs worldwide which contains significant amounts of valuable bioactive substances. Rosehip, white and red grape skin are therefore potentially good sources of natural antioxidants as an alternative to the synthetic antioxidants used in the food industry to prolong the shelf life of food. Although, the content of total phenolics differs depending on the type of material, isolation method and applied solvent. Besides, anthocyanin content in plant material depends on the variety and the harvest year. The present investigation concerns solid liquid extraction from red and white grapes skin and the rosehip (Rosa canina) to attain extracts with a high content of phenolic compounds. Conventional extraction techniques and extraction with supercritical fluids (SCFs) have been carried out and the impact of extraction technique and experimental parameters such as time, pressure, temperature, and solvent mixture were examined. The extracts have been analyzed for the total phenolic content by using Folin- Ciocalteu method. Proanthocyanins were determined by UV spectrophotometry method based on acid hydrolysis and colour formation, and the phenolic constituent profile has been examined by liquid chromatography with tandem mass spectrometry (LCMS- MS) analysis. The qualitative parameter analyzed is antioxidant capacity; determined by 2,2-diphenyl-1- picrylhydrazyl (DPPH) radical scavenging assay. The results demonstrate that the contents of the major constituents significantly varied among t different types of materials. The highest content of total phenolics was determined in the extract from the white grape skin, macerated with MeOH (26.7 mg GA/g extract), and similar, 25.6 mg GA/g extract in the MeOH extract attained by Soxhlet. Ellagic acid (0.650 mg/100 g extract), catechin (0.164 mg/100 g extract), gallic acid (0.133 mg/100 g extract) as well as caffeic acid (0.038 mg/100 g extract) are the major compounds present in the rosehip extracts attained by maceration using MeOH as solvent. Modern technologies including supercritical fluids as processing media allow extraction of very pure, high-value products from materials which otherwise would be considered by-products or waste and sold cheaply, or simply disposed of. Such processing concepts promote reuse of residues from food industry. Extraction of plant materials for isolation of natural compounds and their inclusion in high value-added products with specific properties has been considered as a very promising application. [ABSTRACT FROM AUTHOR]