Refined oil that is crystal clear immediately after production sometimes turns cloudy after a few days in storage. This common phenomenon has multiple causes—some natural and harmless, others indicating quality issues requiring attention.
Three Primary Causes of Oil Cloudiness
1. Temperature – Natural Crystallization of Saturated Fats
Oils high in saturated fatty acids remain clear at higher temperatures but become cloudy when cooled. As temperature drops, higher molecular weight saturated fats transition from liquid to solid state and crystallize. For example, peanut oil begins to crystallize and become cloudy around 10°C. Common animal fats are solid at room temperature. This is a natural physical change and does not affect oil quality.
2. Moisture Content – Storage Environment Issue
Refined finished oil is practically water-free and therefore clear. After entering storage tanks, it may absorb moisture from residual water in improperly cleaned tanks or from humid air entering the tank where moisture condenses and mixes into the oil. Moisture significantly impacts oil transparency, causing haziness. This indicates a storage or handling issue that should be addressed.
3. Wax Content – Requires Dewaxing
Different oils contain varying wax levels. Some oils, like common soybean oil, have very low wax content with negligible effects on transparency. Others, like rice bran oil, have relatively high wax content (3-9%) and are naturally cloudy at room temperature, requiring dewaxing to become clear and transparent. Waxes are high-molecular esters that crystallize as temperature drops, causing cloudiness and affecting product appearance.
Additional Factors such as oil oxidation/rancidity, phospholipid content, and other impurities may also cause cloudiness.
How Huatai Solves Cloudiness Issues
- Huatai's refining solutions address each cause through targeted processes:
- Moisture issues are solved by high-vacuum drying with precise temperature control.
- High FFA is removed through deacidification (chemical or physical refining).
- Pigments are eliminated via decolorization with activated clay.
- Odors are stripped away through high-vacuum deodorization.
For oils with high wax content, such as rice bran oil, sunflower oil, and corn oil, Huatai's low-temperature winterization and dewaxing technology removes waxes to ensure clear, transparent oil at room temperature. The process involves controlled cooling to crystallize waxes, followed by filtration for removal. Optional polishing with perlite further reduces wax residue below 50ppm for premium-grade oil.
Why Choose Huatai Group
With 38+ years of grain and oil machinery expertise, Huatai delivers complete turnkey refining solutions that prevent cloudiness issues.
Huatai's full refining line includes degumming, deacidification, decolorization, and deodorization, with additional winterization and dewaxing available for high-wax oils. The system features PLC automation for consistent quality and minimal labor, plus energy-saving design with heat recovery to reduce operating costs. Custom capacities range from 1 to 5000 T/D.
Huatai serves 70+ countries worldwide, holds 100+ national patents, and is recognized as a National "Little Giant" Enterprise and National Green Factory. We provide turnkey delivery covering design, manufacturing, installation, training, and 24/7 technical support.
Prevent Cloudiness with Proper Equipment
Proper refining, dewaxing, and storage practices are essential for maintaining oil clarity. Huatai's complete solutions ensure your oil stays clear, stable, and market-ready.
