Experimental cookery

Emulsifying properties of mustard. Kilgore determined the emulsi- fying properties of mustard in three ways: (1) Foaming ability, (2) the stability of oil drops on a mustard solution, and (3) the stability of emul- sions made with mustard solution as the sole emulsifying agent. In a 75- pound batch of mayonnaise about 8 to 9 pounds of vinegar and 5 to 6 ounces of mustard are used, which gives about 3.5 per cent concentration of mustard. The concentrations of mustards used were: 0.1, 0.5, 1.0, 2.0, and 4.0 per cent. THE METHOD OF MIXING 277 Foaming. The mustard was weighed and added to water in glass- stoppered bottles and shaken. Little foam was formed except with the 2 and 4 per cent concentrations. Good emulsifiers for oil-in-water emulsions usually foam readily in water. Oil drops on mustard solution. The mustard solutions were obtained by adding the mustard to water and filtering ofif the residues of undissolved mustard. About 70 per cent of the mustard was found to be soluble. If drops of oil such as corn oil are poured on water, they spread in a film over the surface of the water. But when drops of oil are placed on water containing an emulsifying agent which favors the formation of an oil-in- water emulsion, spreading does not occur. The drops remain separate and distinct. Kilgore found that a 1 per cent mustard solution afforded protec- tion for the oil drops but a 4 per cent solution gave much greater protection. Stability of mustard emulsions. The corn oil was added slowly to the mustard solution as in making mayonnaise, a high-speed drink mixer being used as a whip. After being stored for one year the emulsions made with 0.1, 0.5, and 1.0 per cent of mustard were broken. Those with 2.0 per cent had some oil on top ; and the emulsion with 4.0 per cent mustard did not break and showed no leakage of oil, although it contained 80 per cent of oil. Corran formed a water-in-oil emulsion of olive oil and lime water. To this emulsion mustard was added. When the concentration of mustard reached 2 per cent, the emulsion broke and reformed as an oil-in-water emulsion. Fine mustard flour was more efficient than coarse mustard flour. Kilgore in continuing his work with mustard and emulsification found that mayonnaise without mustard had a stififer consistency than that with a de-fatted mustard flour. But he found this depended on how the mustard was added. If added dry it decreased initial stiffness, but if added wet it increased the stiffness. De-fatted yellow mustard flour lost its emulsifying properties if mixed with vinegar and allowed to stand longer than a day; whereas this was not the case with mustard having a high oil content.