Sunflower Oil Production Process Introduction

Sunflower oil is an excellent vegetable oil which is extracted from sunflower seeds that begin with sunflower seeds pre-treatment, pre-pressing, embryonic material leaching, wet meal desolventizing and crude sunflower oil refinery process. Sunflower seed oil is rich in linoleic acid, which helps reduce blood cholesterol levels in the body, and is beneficial to protect cardiovascular health. Besides the unsaturated fatty acids, sunflower oil also contains vitamins E, folic acid, iron, potassium, zinc and other essential nutrients.

sunflower seed pre-press and meal extraction process

Currently, the sunflower oil sold on the market is mostly produced by de-shelled pre-squeezing and leaching process. De-shelled pressing-leaching technology is the key point of sunflower oil production line which avoids the negative impact of over-refining, high temperature, and acid and alkali effects on oils, so that the nutrients in the oil can be well preserved. For example, the content of vitamin E in de-shelled squeezed sunflower oil is 75.5mg/100g. However, by squeezing-leaching seeds with shell, every 100g sunflower oil only contains 41.62mg vitamin E. What’s more, there is no contact with alkane in the process of the un-shelled pressing-leaching process, which avoids the formation of trans fatty acids.

Sunflower Oil Processing Steps

The processing characteristics of first-grade sunflower oil are: First of all, sunflower seeds are selected and cleaned to remove impurities, and then the seeds are de-husked and crushed. After that the embryo is flaked and steamed in the frying pan, the fried product is pre-squeezed out of the oil and the remaining oil is extracted by solvent leaching, then the crude oil is purified through precipitation and filtration. Finally, the oil is dissolved, degummed, decolorized, deacidified and deodorized into the refined oil. More specifically, the operation steps and equipment for processing sunflower oil are as follows:

Select the sunflower seeds with the oil content of 30~50%, and the seed material contains certain impurities (sediment, stones, iron filings, etc.) which should be removed by cleaning sieve and magnetic separator.

Equipment

magnetic separator for cleaning sunflower seeds sunflower seeds cleaning sieve

For sunflower seed, it should be squeezed after shelling, which can increase production capacity and oil quality. After the sunflower seeds are sieved by a vibrating screen and then placed into a vertical centrifugal sheller to separate the shells. After separation, the shell content in the sunflower kernels is less than 10%, and the content of kernels in shells is less than 1%.

Equipment

Sunflower seeds roller shelling and crushing machine

sunflower seeds sheller sunflower seeds crusher

Process features

(1.) The gear roller shelling machine mainly adopts high-speed rotation of the special wear-resistant roller to crush the material (traditional roller crusher adopts low-speed crushing) to form a high-productivity mechanism. The roller sheller consists of a transmission device, a frame part, a crushing roller, a mechanical spring device and a linkage mechanism, etc.;
(2.) The gear roller sheller is divided into double rollers and four rollers (ie, on the two pairs of rollers). It is suitable for sunflower seed shelling and breakage of sunflower seeds, which could ensure that the embryo flaking and sunflower seed pre-pressing, and it is the key equipment for the pretreatment production line; (3.) The gear roller sheller has the advantages of small volume, large crushing ratio, low noise, simple structure, convenient maintenance, high productivity, the uniform particle size of the broken material, easy maintenance, sensitive overload protection, safe and reliable features.

Rolling the embryo is to grind the broken oilseeds into embryonic flakes with a certain thickness, which is an important process of pretreatment. Its role is to destroy the cell tissue so that the oil can be easily extracted.

Equipment

Embryo flaking machine

sunflower seeds flaking roll machine

Process features

(1.) It can increase the surface area of seeds and reduce seed thickness, which could not only increase the ability of seeds for absorbing moisture and heat but also speed up the moisture evaporation in steam frying process;
(2.) The machine has large daily output, stable operation, and reliable hydraulic system pressure. What’s more, there is a buffer device between the rollers to reduce the collision between the rollers and increase the service life of the rollers;
(3.) embryo flaking machine has characteristics of large processing capacity, rolling embryo evenly, good stability and operability.

Heat treatment is one of the most important processes in the extraction of oils, including the wetting and heating of the sunflower seed. In the production, it is called embryo steaming or frying, and the steamed and fried embryo is called a matured embryo. The heat press of the embryo is called hot pressing and sunflower seeds are mainly hot press. The heat treatment has a direct impact on the smooth progress of the entire oil production process, the level of oil output, and the quality of oil products and cakes.

Equipment

The steam frying pan

steam fryer

Process features

(1.) The steam frying pan is a processing equipment that wets and steams the embryo flakes to prepare mature embryos, so as to meet the technological requirements of the oil extraction. Our steamer can also be used as a softener.
(2.) Our steam cooker has features of condensing oil and improving oil yield, which is a necessary equipment for plant oil pretreatment in vegetable oil plants; (3.) It can adjust the oil structure to prevent blocking the oil.

steam fryer

In production, people mainly adopt pre-squeezing and solvent leaching methods for oil extraction of sunflower seed. Pre-press can squeeze out some of the oil in the raw material to improve the oil effect.

Equipment

ZY24(202-3) oil pre-squeezing machine, solvent leaching device.

Process features of ZY24(202-3) oil pre-squeezing machine

sunflower oil pre-pressing machine

(1.) 202-3 type spiral press machine is suitable for pre-squeezing and leaching methods or two times crushing process in the vegetable oil factory, and it is suited to process seeds with high oil content like sunflower seed;
(2.) After pre-squeezing, the structure of squeezed cake is loose but not crushed, which is beneficial to solvent permeation, and the oil content and moisture of cake are suitable for leaching;
(3.) The quality of the extracted oil is better than one squeezing or one leaching of oil.

Capacity: 45-50T/24H(Take sunflower seed for example)
Residual oil in the cake: 13%around(In the normal condition of pretreatment)
Power: Y255M-6,1000R/M,30kw,220/380V,50HZ
Net weight: Nearly 5500kg
Overall dimension: 2.90×1.85×3.64m

Process features of solvent leaching device

(1.) After squeezing, the squeezed cakes are sent to be leached for extracting oil, then the extracted oil can be refined, and the solvent is usually No. 6th gasoline. For wet oil meal desolventizing: the oil meals which discharged from the leaching device contains 25%~35% solvent and should be removed by drying & cooling the cakes in a desolventizer-toaster, and the extracted solvent could be recycled for next use. Meanwhile, the mixed oil which discharged from the leaching device is purified by steam evaporation, stripping, and sedimentation-filtration;
(2.) In the production, solvent recycling can reduce solvent consumption, improve product safety and product quality;
(3.) Please note: pre-squeezed leaching process is suitable for the larger scale sunflower oil production line(30t/d or above).

The steps of sunflower oil refining are basically the same as those of other vegetable oils, including degumming, alkali refining, decolorization, deodorization, and dewaxing. The refined product is not only light in color, but also has high nutritional value and good taste. It is a good edible oil.

sunflower oil refining process

Equipment

Alkali refining pot, degumming machine, decoloration pot, deodorization pot, crystallizing tank, dewaxing press filter, oil pumps and other parts.

Process features

(1.) Degumming: when the intermittent process is used, refining consists of heating the oil to between 40 and 85℃, by adding the concentration of 85% industrial phosphoric acid which accounts for 0.1%~0.2% of oil content to the crude oil, the mixture should be stirred for 0.5 h for degumming;
(2.) Alkali refining: then the alkali is added to remove the acid by adding the lye. The excess alkali content is 0. 2%~0. 4% of the oil weight;
(3.) Washing: the oil is washed under the absolute pressure of 8kPa (vacuum degree is above 700mmHg) at the temperature of 90~95℃, and then is vacuum dehydrated by dryer;
(4.) Decolorization: the active white soil which accounts for 4%~6% of the oil-heavy is added to adsorb pigments for decolorization, then the waste white soil is filtered;
(5.) Deodorization: the decolorized oil needs to be placed under vacuum pressure at the temperature of 230~250℃, and is distilled by passing 0.1~0.2MPa direct water vapor for more than 4h, then through cooling and fine filtrating.
(6.) Dewaxing: the deodorized sunflower oil also contains a small amount of wax, which is pumped into a pre-cooled crystallization tank and cooled at a certain cooling rate in 8 hours, in order to speed up the reaction and uniform cooling, appropriate mixing is necessary, and stirring speed can be 10~15r/min. After the oil is cooled and crystallized to a certain temperature, stirring is stopped and the crystal keeping time is maintained for 12 hours in the crystallization tank. After that, the oil and wax are separated by press filter, using compressed air. The discharged liquid oil is the finished sunflower oil, which can meet the standard of high-grade cooking oils.

Features of Sunflower Oil Production Line

Characteristics of the oil pressing and extracting

  • Compared with other oil extraction methods, the oil pre-pressing has the advantages of simple process, less supporting equipment, strong adaptability to oil varieties, flexible production, good oil quality, light color, and pure flavor.
  • However, the cake has a high residual oil content after squeezing, resulting in high power consumption and easy loss of parts. This method can be used to extract oil from peanuts, rapeseeds, sunflower seeds and other seeds or nuts. At the same time, the pre-pressed cake is sent to the leaching workshop to further extract the residual oil in the cake to achieve a better oil-making effect.

Characteristics of the oil refining process

  • For the refining part, we provide a full set of equipment for batch refining process, semi-continuous refining process, and full continuous refining process(more than 50 tons per day).
  • Batch refining process has a daily capacity of 1~30 tons of sunflower oil.  It has features of less investment, convenient operation and small footprint.
  • Semi-continuous refining process has a daily capacity of 30~50 tons of seed oil. It can be used for different types of oil refining, and it has advantages of low power consumption, better refining rate than batch-type and traditional semi-continuous processes.
  • Full continuous refining process has a production capacity of more than 50 tons per day. With characteristics of high refining yield and low consumption of auxiliary materials, full continuous refining process can meet the requirements of deep processing of products. The process requires continuous operation, which is suitable for larger scale production of the continuous production enterprises.

Sunflower Seed Oil Application

sunflower seeds and sunflower oil

Sunflower oil is a high-quality edible oil known as “nutritive oil”, which has become the preferred oil for consumers and chefs. And the worldwide consumption of sunflower oil ranks third in all vegetable oils. It is generally used for cooking, for example, it is used to make margarine, mayonnaise, salad dressing and salad oil. The artificial cream obtained with sunflower oil has excellent taste and high unsaturated fatty acid content. In the food industry, sunflower oil is also used to make fried fast food, such as potato chips and corn chips. The sunflower oil cake which obtained after squeezing contains 30%~36% of protein and 8%~11% of fat. In addition to feed, oil cake can also be used to produce monosodium glutamate and soy sauce. The protein in the sunflower kernels is composed of reasonable amino acids and can be used to make edible protein powder. The sunflower shell can be used as a fuel to generate steam and electricity, as well as animal feed and furfural production.