Agar is another example of a phycocolloid (a colloid extracted from seaweed). It was actually discovered years before the other 2 phycocolloids (carrageenan, and alginate). Agar is a very versatile gelling agent. It forms thermo-reversible gels that gel when cooled and melt upon reheating. When using agar it is good to know that even the smallest concentrations (.2%) can create a stable gel. When used as your sole gelling agent agar forms brittle gels with a very short texture. I have used agar for a variety of different applications in the pastry kitchen. One of the biggest uses that I have come across is "fluid gels". Basically a fluid gel is a gel that has been set and then reblended to form a "thickened" sauce or puree. Agar can also be used in conjuction with other hydrocolloids to form a wide range of textures. One of the most common synergies is the agar/ locust bean gum (LBG) concentration. By adding a small ammount of LBG to your recipe you can vastly change the outcome of the gel. The gel strength will be increased, and the texture of the resulting gel will become more elastic. This can provide a better mouthfeel when eating the gel. Agar gels also have the ability to become heat stable to a point. Gels made using agar can be held at temperatures up to ~80 C before remelting. This can be a desired property if your trying to make a "hot gel". Below is a basic fluid gel recipe using agar.
.5 ascorbic acid
Bloom gelatin in ice water
Sheer agar, ascorbic, and sugar into liquid
Bring the liquid to a boil while whisking
Simmer for 1 minute
Take off heat, and add bloomed gelatin
Poor out and leave to set
Vitaprep the gel smooth
Wednesday, September 22, 2010
I was not able to attend the NYC starchefs, but have been hearing many great things about the demostrations and presentors. If anyone has attended and would like to post a comment about your experience I would love to hear any feedback. I do know that they have a few more classes/demos today, I am not sure what the scheduel is like for tomorrow. Please fill me in, I am dying to know details.
Saturday, September 18, 2010
Wednesday, September 15, 2010
I have used a variety of different cream chargers. I have found that the iSi Thermowhip works the best for me. If you dont already know what an iSi creamer is I will tell you. They are a brand of cream chargers originally meant to make whip cream at home. It is basically a metal canister that holds liquid or other ingredients, it is air tight, and when used in conjuction with either Co2 or No2 you can make a variety of whipped or soda charged recipes. I really like the thermowhip because you can hold hot or cold ingredients in it without having to reheat or chill the canister before use. Cream chargers are very versatile tools in the pastry kitchen. You can make a wide range of recipes: foams, espumas, drinks, cakes, soups, sauces, whipped creams, etc. Below is a basic chocolate mousse recipe that can either be used hot or cold, I prefer hot.
500 Chocolate 64% or 72%
200 Whole Milk
1ea. Used Vanilla Bean
Sous Vide all ingredients together in a bag
Place bag in hot water to melt
Remove vanilla bean and poor into iSi Thermowhip
Charge with 3-4 Cream Charges
Sunday, September 12, 2010
One must lead to the next. Lets first discuss the definitions of each term as they relate to hydrocolloids. Dispersion is a mixture of two components that are not alike. This usually relates to the chemical (hydrocolloid) that is being used and an aqueous solution (water). Hydration is the process when the chemical (hydrocolloid) binds with the aqueous solution (water) and becomes fully dissolved. Now that we have gotten the definitions out of the way I can explain some of the different methods in which to disperse and hydrate your hydrocolloid. There are a few different ways in which to disperse hydrocolloids. First and foremost not all hydrocolloids can be dispersed in the same manner. When adding your hydrocolloid it is important to know whether or not it can be dispersed using cold water or hot water. It is also important to know if the the said hydrocolloid should be mixed with another ingredient before being added to the water. In most cases the hydrocolloid can be dispersed easier if mixed with sugar, oil, and/or alcohol. Now that your gelling agent has been dispersed in your liquid it must be hydrated in order to achieve the desired set. To properly hydrate your gel there are a few different methods that you can take depending on what it is that you are gelling. Under most circumstances a strong sheer may be used. Either a hand mixer or even better the vortex of a vitaprep will work. You may also need to heat or cool your dispersion in order to achieve a fully hydrated gel. There are a few signs that you have aquired a properly hydrated mixture. The mix may appear to swell or become more viscous. This is a good indication that you have properly hydrated your gelling agent. You can now leave your gel to set. You disperse to hydrate.