Emulsionantes por Laiskonis: emulsifiers are a group of compounds in ice cream which aid in developing the appropriate fat structure necessary for the smooth eating and good meltdown characteristics desired in ice cream. Milk proteins act as initial emulsifiers and give the fat its needed stability. Supplemental emulsifiers are added to ice cream to actually reduce the stability of this fat emulsion by replacing proteins on the fat surface, leading to a thinner membrane more prone to coalescence during whipping.
Emulsifiers are characterized by having a molecular structure which allows part of the molecule to be readily “anchored” in water (hydrophilic), and another part of the molecule to be more readily “attached” to fats (lipophilic). When we use egg yolks in an ice cream base, the 10 percent lecithin that they contain performs this function to some degree. Common emulsifier additives used in commercial stabilizer blends include mono- and di-glycerides or polysorbate 80.
Emulsionantes en Under Belly
Proteínas de suero de leche desnaturalizadas por Paul Raphael
They partially denature over time above 60°C / 140°F. They don’t fully denature until they reach 90°C / 194°F or higher. When they fully denature, some may form insoluble aggregates that are harmful to the ice cream's texture.
When they partially denature, they develop different kinds of molecular attractions. Some of them are attracted to the casein micelles. When they bind to the casein micelles, they form stronger bonds than the casein’s original bonds to the fat globules. When enough of this happens, the emulsion partially
destabilizes—which is exactly what we use all those other emulsifying ingredients for.
Other denatured whey proteins are attracted to each other. At some temperatures they begin to form aggregates that make a gelatin-like network in the water phase of the ice cream. Which is to say, they behave like a hydrocolloid stabilizer (see the post on Stabilizers).
Paul Raphelson esta a favor se usar solo dos yemas por litro de leche
Yolks contain a number of proteins and lipids that work as emulsifiers. By far the most important among these is lecithin. For adequate effect on ice cream emulsification, the mix requires 0.5% to 1% egg yolk. This equals 1/3 to 2/3 yolk per liter of mix, so a single yolk is more than adequate. 2 yolks (3 to 4%) are necessary to get significant thickening / stabilization. For the richest French custard-style ice creams, 4 to 6 yolks per liter is more common, with 8 to 10 being close to the outer fringe.
