STUDY OF THE FOAMING PROPERTIES OF GELATIN WITH SOLUBILIZED SUBSTANCES FOR THE PRODUCTION OF MARSHMALLOWS

The article presents the results of studying the foaming properties of gelatin with solubilized substances by Rauch’s method. To improve the nutritional value of gelatin, deodorized refined sunflower oil with β-carotene was used. It has been proved that gelatin with solubilized substances can be used in the marshmallow technology with natural colourants obtained from the roselle (Hibiscus sabdariffa) and the black chokeberry. It has been established that a gelatin solution with solubilized substances has the greatest foaming ability and maximum foam stability at the rotation frequency 30–80 s-1 and a temperature below 45°C, with pH=3–7 within (6–8)×60 s. It has been found that aqueous extracts of natural colourants of anthocyanin origin - cryopowders obtained from the roselle and the black chokeberry - reduce the maximum foaming time to 3×60 s, as compared to water. The maximum foam stability was observed after (3–4)×60 s and was 70 and 60%, respectively, which exceeded this value of the control sample by 20–30%. The foam stability remained unchanged for (2-5)×60 s due to the presence of phenolic compounds in the extracts. 40% aqueous-alcoholic extracts of cryopowders of the roselle and the black chokeberry should be introduced after whipping the gelatin solution, since in this case, foam breaking is minimum. The foam stability increases from 60–75 to 94–99% after the introduction of 20–60% of sugar. It has been established that the use of gelatin with solubilized substances in the marshmallow technology with natural colourants from the roselle and black chokeberry makes it possible to obtain products with a density of 510–670 kg/m3 and ensure the compliance of this quality parameter with the requirements of the current regulatory documentation.