in our previous video we discussed the definition of an emulsification and how we can use shearing power to reduce surface tension while combining fat and water together creating an emulsified State now we came to the final conclusion however that emulsions by Nature are basically unstable so the way that we can stabilize these emulsifications and keep them from coalescing or breaking on us is by using emulsifiers and stabilizers now emulsifiers and stabilizers are two different things that serve the same end goal the two basic types of emulsifiers that you're going to be using in your kitchen are number one amino acid chains and these amino acid chains there's some of them that have fat friendly receptors and water friendly receptors so when these are used in an emulsification when they are mixed together you have one portion of this amino acid chain that will link to fat and the other portion which will link to water and because this amino acid chain is capable of linking fat and water together it is by definition an emulsifier now when these amino acid chains when they link together and form larger chains they will create what we call proteins and so there are some proteins out there that will act as emulsifiers with the most common one being casin which is commonly found in egg yolks and milk products now the second type of emulsifier out there are phospholipids like leian and the way that these phospholipids work let's let's say we have our water molecule here H2O and we have a fat molecule hanging out right next to it and this is going to be a generic fat molecule that's going to represent olive oil canola oil whatever you're using to make your multication and you add some leathan to the mix and what happens is lethan has a water soluble head and a fat soluble tail so it can actually link the fat and the water together now anytime you have an emulsifier that has has a water soluble head and a fat soluble tail these are called surfactants and surfactants work by decreasing surface tension because surface tension as we defined in our previous video is a fact that two molecules or two chemicals that don't like to mix they align themselves in such a fashion to where they will touch as little as possible well now these surfactant come along and they link these together diminishing what we call interfacial tension which is the tension between the two interfaces of the two of of the of the continuous phase and the dispersed phase so it decreases this interfacial tension and it links them together which decreases or completely diminishes surface tension and allows them to freely mix which is the definition of an emulsification now some phospholipids like lethan will also have the added benefit of a positively charged fat tail and this is cool because then when it comes into contact with other fat molecules that are in in the same Emulsion those fat tails are also positively charged so they will actually push each other away they will not want to combine with one another because they will be the two positive charges will basically be pushing each other away and this will keep the fat molecules or the fat droplets from coming together and coalescing or pooling together which will eventually lead to coalescent which will then break your sauce now these little Doodles are are for just visualization purposes only uh this it's not really what a amino acid chain looks like or a um leian looks like but you know they're here just to basically illustrate how amino acids phospholipids and surfactants work as emulsifiers now common emulsifiers that you're going to come by a big one that's commonly used are egg yolks and you'll find this in things like uh you know hollay aoli mayonnaise and egg yolks are extremely powerful emulsifiers because they contain leian which is a Sur faant and also protein and the protein is mainly casin protein which is made up of these amino acids that link together and these amino acid chains that make up the casin have both fat friendly and waterf friendly receptors on them and this is the same deal with milk and cream and why milk and cream can be used as emulsifiers because they also contain a decent amount of CAS and protein which can be used as an emulsifier and then you have mustard which technically the melage in the Mustard Seed coating is a very powerful surfactant and this is why you will commonly see it called for in a vinegret recipe cuz not only does it add a nice flavor profile to vinegret but it works as an extremely powerful emulsifier to link the vinegar and the oil that are used in the making of a vinegret now whereas emulsifiers will actually link fat and water together stabilizers on the other hand will just get in the way of the dispersed phase now it's important to note that to my knowledge most most of these stabilizers are all water soluble so normally you're going to be using a stabilizer when you are making a fat dispers to water emulsification and the way these work is these large molecules will actually get in the way of the dispersed fat uh creating a sort of barrier and uh not allowing the fat to come together pool cool less and break your sauce now these large molecules can anything from proteins to starches uh pectin uh plant particle think plant purees and food grade gums my personal favorite for uh stabilizing emulsions now Inseparable from this concept is the fact that these large molecules will also add viscosity to your mixture and so because these large molecules are water soluble you are going to start with water as your continuous phase you will add in uh some of these large molecules whether it's some plant puree where you know could be tomato puree carrot puree whatever food grade gums maybe some starches maybe some pectin and so you add this into your water phase or excuse me your continuous phase which is your water and this increases your viscosity because anytime you add large molecules it's going to increase your viscosity of your water but viscosity in itself during the emulsification process will work as a stabilizer and how this happens is the thicker your continuous phase becomes that thicker continuous phase will create more drag on the dispersion phase which is going to be your fat in this case which will increase the shearing power which we use to break up our dispersed phase or our fat which will decrease the particle size of the dispersed phase and as we talked about in the last video the smaller you can get your dispersed phase the more stable your emulsification will be so this is an important concept to understand because you can actually use purees and plant particles and proteins and starches to stabilize your emulsions and you can add them to your water phase before you even start or excuse me you can add them to your continuous phase which is your water because they are water soluble before you even start the emulsification process before you even start adding in the fat and that viscosity is going to give you a smaller dispersion phase a more stabilized Emulsion and then you're going to be left in this stable Emulsion with these large molecules that will keep the fat from coming together and coalescing and breaking your sauce so they do double duty now this is why one of my favorite stabilizers is xanthan gum and this is because zanth and gum will add viscosity uh to a water-based liquid and you only have to use a very small amount usually about half a per by weight or less and it has no perceptible Flavor now it also has a wide range of phes in which it works so it makes it fairly versatile and also making it more versatile is the fact that it will hydrate in both hot and cold water but the my favorite part about xantham gum which kind of separates it from some of the other food gums and uh some of the other stabilizers is the fact that it's what you call sheer thinning and sheer thinning basically means that at rest it will be thicker than when being sheared which is applying Force like stirring or chewing or uh blending whatever you're doing right and so the way I like to visualize this is here's my little grid and here is my emulsification at rest and the horizontal and vertical lines represent the fact that my continuous phase which is my water is a little bit thicker at rest which is keeping which is helping to keep my spersed phase from coming back together pooling coalescing and breaking my sauce and so this is why in future videos uh actually a video that I have in the queue right now that I'm getting ready to release is how to make a stabilized bur Blanc using xantham gum and the re and the fact that I can make a lemon bur Blanc because it's a xanm gum will hydrate in a low ph and it is sheer thinning and I can use it in both hot or cold water and it adds that viscosity makes it an extremely useful stabilizer in your kitchen