I would like to make an ice cream based on sesame oil and allulose. According to reasons-for-separating-eggs-in-ice-cream, ice cream can be made French-style with milk, cream and yolk, or Philadelphia-style with milk and extra cream. In either case, the creamy consistency is actually achieved by partially “demulsifying” the mixture of milk and cream, either with yolk lecithin, which is a worse emulsifier than casein, or with extra cream. So, I am wondering if it is possible to mix sesame oil, allulose, emulsifiers and possibly stabilizers to achieve a comparable texture.
To get the proportions, I converted all the butter, cream and MCT fat of this Philadelphia-style recipe:
3 tbsp butter (34.5 g of fat), 1/3 cup allulose + 1/4 MCT (56 g) + 3 cups heavy cream (257.6 g of fat)
into the equivalent in terms of sesame oil and water:
1/3 cup allulose + 1.55 cups sesame oil (348.1 g) + 1.4 cups water (to match the volume of 1.) + yolk/lecithin/glycerin/casein?? (to emulsify).
(If I use yolk, there will be more fat. More on that below.)
I haven't found practical guidelines for producing emulsions as related to ice creams, but I got some clues from this research paper comparing emulsions with soy lecithin vs. yolk lecithin. They mixed the emulsions at 50°C. At the conditions they tested, they found that the most stable emulsion was produced at 50:50 oil:water mixture with 5% soy lecithin at neutral pH with the addition of xanthan gum as a stabilizer. On the other hand, the yolk lecithin emulsion was more stable against oxidation; moreover, the most stable egg yolk lecithin was produced at pH 2.3 and also at 50:50 oil:water and 5% lecithin. The reason for the difference in pH has to do with the fact that yolk lecithin is richer in phosphatidylcholine and phosphatidylethanolamine, which are zwitterionic, whereas soy lecithin is richer in anionic phospholipids such as phosphatidylinositol and phosphatidic acid.
Should I decide to go with yolk, my preferred choice of lowering the pH would be with vinegar, which has a pH ≤ 2.5. However, that would probably be wasteful, especially because the acetic acid would rapidly volatilize at 50°C. Do I have any other options besides citric acid? Or is it possible that the zwitterionic compounds in yolk lecithin also emulsify well at basic pH, given that the hydroxide anion is an intrinsic emulsifier? In that case, could I use sodium acetate in a sweet ice cream?
To get 5% of lecithin from yolks requires y ≈ 14.9 yolks since the yolk of a large egg has 4.4 g of fat and yolk fat is 30% lecithin (from the equation 5%(348.1 + 70% 4.4y) = 30% 4.4y).
Do all these ingredients seem to be in the right proportion? Will it be possible to create the emulsion with just a spatula and a pot?
Finally, how do other solids (i.e. allulose, xanthan gum, etc.) interact with the oil? Instead of xanthan gum, would collagen, resistant corn starch and chitosan be good stabilizers?