How I long for thee, Mayo.
Besides the obvious fact that mayonnaise is the KING of condiments, store bought mayonnaise is normally loaded with preservatives and crap (not to mention expensive). In order to avoid the soy by-products and modified (hydrogenated) corn/soy oils you need to go organic. Who wants to spend $10 on a little jar of organic mayonnaise? Not I.
Science you say?
Technically, mayonnaise is an emulsion (or in cooking terms an emolient). An emulsion is a mixture of two dissimilar liquids. Generally speaking, a mixture of polar and non-polar liquid molecules forms an emulsion. i.e oil and water. In the case of mayonnaise, we are mixing a non-polar oil with a polar acid (i.e lemon juice, wine vinaigre, balsamic, etc). You will notice that mayonnaise doesn't come out of the jar separated into its base components. It arrives as a white, creamy delicious spread. In order to prevent an emulsion from separating we need to use an emulsifier.
Enter the EGG! Egg yolks contain lecithin. Lecithin is the powerful emulsifier and thickener that is responsible for a number of culinary crimes including boiled custards (bleck!!). Lecithin is an example of a phospholipid. Phospholips contain both a polar AND a non-polar end. This means that it can play nicely with oil AND water at the same time. Emulsifiers stabilize emulsions by surrounding both the polar AND non-polar molecules in a warm fuzzy embrace (Well not quite, but it helps prevent separation...just like hugs)
The egg whites contain albumen, which is an extraordinary example of a protein. This protein when whipped can slowly unfold itself and increase in volume by up to 8 times their original volume. (substantially reduced volume in the presence of any fat mind you.)
Follow along noble foodies, you are about to enter Sandwich Nirvana
Classic French Mayonnaise
2 tsp of white wine vinegar
1 egg yolk (or whole egg, your choice)
1 cup of neutral oil
1/2 tsp of salt
I like to add a squirt of Dijon mustard, it adds an extra something-something that really "kicks it up a notch". Don't get all held up on the types of oils and acids. This will work with any oil and any acid. Try mixing white and red wine vinegar. I like to add more acid than strictly necessary (up to a whole lemon, but this might be too much for most people), as I like a really tangy mayonnaise. Just start with 2 tsp to see how you like it though. Live a little and experiment you can always whisk in some more at the end.
I don't care what you say. Mixing Hellman's and garlic is not freaking aioli. To be perfectly snooty, aioli is ONLY aioli when the mayonnaise is made with lemon juice, crushed garlic, salt and a good peppery extra virgin olive oil. Add some pepper if you are cheap like me and can't afford the good olive oil. Use the above recipe but substitute the neutral oil with the olive oil, throw in a minced and crushed clove of garlic, and only use lemon juice. Seriously, try it.
Other amazing mayo combinations
Lime and Cilantro (heavenly with grilled sea-bass or a tar-tar replacement)
Lemon (some zest as well please) and shallot. (You MUST try this with roasted veggies)
Dill, Lemon, and a touch of sugar
Dill Aioli (an awesome tar-tar sauce replacement)
Chipolte, cumin, garlic.
Wasabi Mayonnaise with grilled tuna, salmon or beef.
Horseradish mayo with rare roast beef.
Add some sugar, replace vinegar with water (or brandy), and vanilla for a fruit dip.
It is pretty easy to just make a basic mayo recipe and then blend in the above ingredients to taste in small batches. When it comes to garlic, I find it works best if you mash it, crush it, and mince it before you blend it. It mixes in more evenly this way.
There are a number of traditional/common methods of making mayonnaise. Generally, they are time consuming, frustrating and generally a PITA to do and clean up (i,e a whisk and bowl, or a food processor) .
Follow my directions, and you can have mayonnaise in one minute flat.
Add ALL of the oil to immersion blender pitcher
Add the seasonings, flavorings and any extra's
Very very gently add the egg. You want to keep it all in one piece
Submerge the immersion blender right to the bottom (gently now)
Pulse 2-3 times for 1-3 seconds. This will get the emulsion going.
Slowly bring the immersion blender to the surface pulsing all the way.
Really give it a good blend now.
Tightly covered mayonnaise should last 7-10 days. The fat picks up the smells in the fridge after a while, which spoils it.