1. A powder composition for producing a hot beverage with foam on its surface, in particular a coffee or cocoa beverage, comprising: a foaming or whitening component in the form of particles； a combination of a bicarbonate or carbonate salt and an amphiphilic substance； and an optionally soluble flavor component in particulate form, in particular instant coffee or soluble cocoa. 2. A composition according to claim 1, characterized in that the combination of a bicarbonate or carbonate salt and an amphiphilic substance contains agglomerates of particles of a bicarbonate or carbonate salt and particles of an amphiphilic substance. A composition according to claim 1, characterized in that the combination of a bicarbonate or carbonate salt and an amphiphilic substance contains particles of a bicarbonate or carbonate salt that are partially or fully coated with an amphiphilic substance. A composition according to claim 1, wherein the amphiphilic substance is a salt or a fatty acid, preferably a divalent salt of a fatty acid, more preferably a calcium or magnesium salt of a fatty acid. A composition according to claim 4, characterized in that the amphiphilic substance is a salt of an unbranched or branched fatty acid having 6-24 carbon atoms, in particular a saturated, unbranched or branched fatty acid having 6-24 carbon atoms, more preferably a stearate salt. 6. A composition according to claim 1, characterized in that the bicarbonate or carbonate salt and amphiphilic substance contains an additive for improving flowability or an anti-blocking agent, such as an inorganic oxide or phosphate salt, preferably an inorganic oxide selected from the group of dioxide1. Порошкообразная композиция для получения горячего напитка с пеной на его поверхности, в частности напитка кофе или напитка какао, содержащая:- вспенивающий или забеливающий компонент в форме частиц；- комбинацию бикарбонатной или карбонатной соли и амфифильного вещества；и необязательно- растворимый вкусовой компонен
