The best production processes and storage to obtain highest quality sunflower oil must take into account chemical and physical factors. Sunflower oil is a delicate vegetable oil that should be handled with caution to preserve most of its characteristics.
Production processes for quality sunflower oil
Sunflower seed oil starts its production process from the cleaning seeds. Seed grinding is next followed by, pressing and extracting crude oil from these seeds, and then refining the oil before packaging. Hexane is a volatile hydrocarbon that is used to extract oil.
Cleaning: The harvested sunflower oil seeds are passed over magnets to remove any metal traces and other impurities. The seeds are then cleaned through a sieve and destructors to remove any remaining contaminants. The outer covering of the seeds is removed to get the pure seeds.
Grinding: The de-hulled seeds are ground into a coarse meal to provide a larger surface area for the press. Hammer mills or grooved rollers are used to crush the coarse meal into small, uniform pieces. The meal is heated so that the oil can be extracted, though impurities are released during this process. These impurities should be removed before the oil is declared edible.
Pressing: The hot meal is sent to the pressing chamber that gradually increases pressure from 60 kPa to 950 kPa and from206 Kpa and 850 KPa with the meal passing through a barrel. The oil is extracted from the barrel at the same time as it is squeezed out through the slots.
Extraction with solvent: The volatile hydrocarbon solvents are used to extract the remaining oil, in order to obtain the most valuable products. Hexane is the most commonly used solvent to dissolve oil cake. The solvent is removed from the oil by distillation, then the matter is passed through it and the solvent is collected at the bottom.
The majority of the volatile solvent is removed from the extracted oil during evaporation, and it can be reused. A stripping column is then used to extract the remaining solvent. In this process, the oil is boiled by steam and the solvent is evaporated, condensed, and collected separately.
Refining process: The refining of sunflower oil involves removing the bitterness, color, and odor. The oil is heated between 40°C and 85°C. The alkaline substance is mixed with the cremated remains to make the remains alkaline. The oils are degummed by heating them to between 85°C and 95°C or by adding acid to the water. This removes most of the gums that are usually made up of phosphates. Centrifugation is then used to remove the sediment and waste products.
The edible oil used for cooking is obtained by filtering it through activated carbon, activated clay, or fuller’s earth, which adsorbs the pigmented substance from the oil. However, the oil intended for salad dressing must be refrigerated. This type of oil is obtained by rapidly chilling and filtering it to remove waxes. To prevent the solidification of oil in the refrigerator, this procedure is used.
The final step in the process is to deodorize the oil by passing hot steam over it in a vacuum at temperatures between 225°C and 250°C. This allows volatile components that produce taste and odor
to volatilize from the oil. One percent citric acid is added to the oil to inactivate any trace metals and prevent them from oxidizing. This prolongs the shelf life of the oil.
Storage of sunflower oil
Some oils like sunflower oil and olive oil are more sensitive than other oil types and must be stored in the refrigerator. Note that oils stored in the fridge easily become cloudy. This doesn’t mean that the oils have gone bad, but they may not look as clear. Cold temperatures will help keep the oils fresh for a long time. Before using the oil, remove it from the bottle for about 30 minutes so that it returns to its usual texture.
Always make sure to store cooking oils in a clean jar or container to avoid any potential contamination. Glass or metal containers are the best options for storing food. If you are storing food in the fridge, make sure to use containers that are resistant to cold.
It is important to keep oil away from light to prevent it from deteriorating. Always store them on shelves that are covered and have no direct contact with light. Always check the expiration date before buying the edible oil. For those who make ghee at home, make sure you do small batches and use them in a month.
The best production processes and storage to obtain highest quality sunflower oil.