Neem Oil is a pain to use. Mixing oil and water is difficult. A strong emulsification improves the effectiveness of the neem. Mayonnaise coats a chip because the oil is emulsified with the assistance of the egg yolk. This gives it a thick, creamy texture. We want the bug to be coated in neem oil for as long as possible. Therefore proper emulsification is absolutely critical.
The reason the oil in mayonnaise is easier to emulsify than in a neem plant spray is the lack of protein and lecithin found in the egg. Wetting agents such as Aloe Vera, Yukka etc attempt to address this by decreasing the surface tension of the water making it easier to emulsify. This will give you an emulsified product albeit a fairly weak one. It is perhaps stable for 20-30 minutes at best. Mayonnaise doesn't split after 20-30 minutes because it is a strong emulsification. So first of all I wanted to attempt to improve the strength of the emulsification of the while making neem oil easier to use.
After trying a range of ideas i settled with this recipe. The basic idea being that I emulsify the neem beforehand with the soap nut wetting agent so it can be simply diluted. This allows me to control the initial emulsification process which is very important. The oil and water are chemically bonded together and the stronger the bond to begin with the more difficult they are to break up later on. It also allows for the addition of other ingredients to help the emulsification.
I would be open to including egg white/yolk powder except it is difficult to find organic versions.
Emulsified Neem Oil 1.0
60% Cold-Pressed Neem Oil
40% Dr Forest Natural Wetting Agent (soap nuts, aloe & botanicals simmered in 50:50 water and vegetable glycerine) Full recipe available on openforest.
1% Organic Liquid Soy Lecithin
Mixed using a high powered blender.
Problems
It still solidify's when cold. Who wants to put a bottle in warm water for 10 minutes before using it? It needs to be liquid even in Winter.
Solution
Addition of other liquid that dilutes the oil while minimising any effect reduction from it essentially having less neem oil per ml of product.
Neem Meal Stock
4 litres water
800 grams Neem Meal
Simmer at 85 degrees for 4 hours.
Chill and allow sediment to settle. Strain.
Mix 50:50 with vegetable glycerine.
I have to mix the neem stock with vegetable glycerine to prevent it spoiling. It also adds some viscosity to water to prevent it splitting out and needing to be shaken before use.
Emulsified Neem Oil 2.0
600ml Cold-Pressed Neem Oil
400ml Natural Wetting Agent (soap nuts, aloe & botanicals simmered in 50:50 water and vegetable glycerine) Full recipe available on openforest.
10 grams Organic Liquid Soy Lecithin]
250ml Neem Meal Stock
Further Development Ideas:
How to add protein in some form to aid emulsification.
Alcohol Extraction of Neem Meal included to ensure maximum number of neem compounds present in product. (Test if alcohol has effect on emulsion)
Use a homogenizer to mix the product to create a nano-emulsion aka making it strong as ****.
Incorporate pre-gelatinised tapioca starch to thicken liquid to aid emulsification.