Pure oil is a colorless and odorless liquid in the molten state. It becomes a white waxy solid when solidified. Most natural oils are light yellow to brown and have a certain smell. Various odors are generally caused by non-fermented ingredients. For example, the aroma of coconut oil comes from nonyl ketone, rapeseed oil and mustard oil can produce pungent and odor due to their glucosinolates, and oxidative rancidity can also Produces odor. The color of natural oils is due to the carotenoid substances they contain.
Now let’s take you to understand the three degrees of oil (solubility, viscosity, density and relative density):
Solubility: at 20°C, oil The maximum number of grams dissolved in 100g of solvent is called the solubility of fat in the solvent. Grease is insoluble in water and soluble in most organic solvents. Its solubility in non-polar solvents is greater than that in polar solvents. As the temperature increases, the solubility of water in oils and fats increases. Grease is soluble in ether, petroleum ether, carbon disulfide, chloroform and other solvents, and soluble in hot alcohol.
Viscosity: Viscosity is a measure of intermolecular friction. Grease has a high viscosity, and the viscosity of grease decreases quickly as the water temperature increases. In the process of making oil, the billet is heated, steamed and fried. The purpose is to reduce the viscosity of the oil, increase the fluidity of the oil and increase the oil yield.
Density and relative density: The mass of grease per unit volume becomes the density of grease. The ratio of the density of grease at 20°C to the density of water at 4°C is called the relative density of grease. The relative density of grease is less than 1, generally between 0.9-0.95. Both density and relative density are inversely proportional to temperature. The change in oil density and water temperature is that the density decreases by 0.00064 for every 1°C increase in temperature.