Winterization, oils

Petroleum Oils. When satisfactorily stable kerosene—soap—water emulsions were produced in 1874, dormant (winter) oil sprays became widely used to control scale insects and mites (1). The first commercial emulsion or miscible oil was marketed in 1904 and by 1930 highly refined neutral or white oils, free from unsaturated hydrocarbons, acids, and highly volatile elements, were found to be safe when appHed to plant foHage, thus gready enlarging the area of usefulness of oil sprays (see Petroleum). 

Normally, a winterized oil should remain clear for at least 24 h at 0°C. This corresponds to a wax content of below 50 ppm. 

Table 5 shows the marketing and label strategies for some current marine omega-3 products sold in Halifax, Canada. Obviously samples No. 1 and No. 6 are natural oils. Perhaps No. 5 is simply winterized oil, a process demonstrated in Table 6 for menhaden oil, which follows from the tendency for DHA to be in the 2-position of fish oil triacylglycerols (81). EPA is reputed to be somewhat less specihc. In the absence of 20 1 and 22 1, the outer 1- and 3-positions may, in some molecules, present two saturated fatty acids from 14 0, 16 0, and 18 0 in one triacylglycerol molecule, which leads to the stearine composition of Table 6. 

Depending on time of harvesting, growing and processing technique as well as lemon variety and geographical origin, oils of different qualities are obtained [50-53]. Sicilian winter oils possess the highest priority from a qualitative... 

Grade Prime crude, brown strained, strained, bleached, winter oil, bleached winter white oil. 

Savory, winter, oil. See Winter savory (Satureja montana) oil... 

Winterization of oils is carried out using the same processes as for fractionation but with conditions suitable for the raw material. Thus in the dry process for the winterization of cottonseed oil (Neumunz, 1978) the cooling cycle lasts for 48-60 h during which time the oil temperature is reduced from 35 to 6 °C and the slurry is then held for a further 12 h at 6 °C before being filtered. The long crystallization time is needed to produce a large crystal. When the process is carried out in miscella crystallization is effected in a very much shorter time and yields of the winterized oil are appreciably higher. 

Winterized oils Oils (e.g., fish oils) which have been stored in a cold place for a long time to allow the solid (i.e., mostly saturated) components to settle out. 

As an example, the maintenance of near constant viscosity in motor oils over wide operating temperatures will be considered. In the old days, people changed their oil for summer and winter use otherwise, at low temperatures the summer oil would become too thick, the reverse being tme for using winter oil in summer. Of course, thickness in this case refers to viscosity. The viscosity of today s motor oils bears designations such as SAE 5W-30. According to crankcase oil viscosity specification SAE J300a, the first number refers to the viscosity at -18°C, and the second number at 99°C. The closer the two numbers are, the less the temperature variation of the viscosity. 

Some manufacturers supply both a light-viscosity winter oil and a heavy-viscosity summer oil, while others supply just one. Heavy oil is sometimes thought to be less prone to fly off the chain, but i believe it also has less chance of penetrating to the rivets inside the drive links. This results in inadequate oiling, which can cause the chain to wear excessively, stiffen or break. I use a light-viscosity oil year round. Re-refined, light-viscosity oil gives excellent results, inexpensively. My favorite oil is SAE 10 hydraulic. 

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