SU1735349A1 - Method for removing oxidation products from sunflower oil - Google Patents

Abstract

The invention relates to the oil and fat industry, and in particular to methods of purifying vegetable oil from undesirable substances. SUBSTANCE: wheat flour is used as an adsorbent for oxidation products of an oil during purification with a flour-oil ratio of 1:10, and adsorption is carried out by stirring for 15-20 minutes. 4 tab.

Description

The invention relates to the food industry, in particular to oil and fat, and in particular to methods for purifying food-grade unrefined sunflower oil, which has undergone oxidative deterioration during the storage of oil.

A known method of deodorizing refined vegetable raw materials involves the removal of substances that impart a characteristic taste and smell to the oil by heating the oil in a deodorizer under vacuum to 170–200 ° C, by passing superheated steam through the oil, followed by cooling the deodorized oil and filtering.

The closest in terms of the achieved result of the present invention is a method of regeneration of oxidized oils, involving the processing of oils with an adsorbent, which is used as animal hair in an amount of 9-15 cm per 1 kg of oil, by passing

oil through animal hair, placed on a non-metallic filter wall 1.

The disadvantage of this method is the low degree of oil purification from oxidation products.

The purpose of the invention is the most complete elimination of oxidation products from food grade non-refined sunflower oil.

This is achieved in that the method of purification of unrefined sunflower oil from oxidation products, including their adsorption on the sorbent and separation of the sorbent according to the invention, uses wheat flour as an adsorbent with a flour ratio of 1:10, and the adsorption is carried out by stirring for 15-20 min.

The adsorbing ability of flour is due to the fact that the oxidation products of oils, as the most reactive compounds, interact with

with

WITH

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components of the flour and adsorbed by it. Moreover, wheat flour of the highest, 1, 2 grades as an adsorbent gives almost identical results.

It has been established that wheat flour as an adsorbent for oxidation products of an oil gives a higher effect than other types of flour, for example, rye.

The results of the experiments are given in table. 1 (the ratio of flour and butter is 1:10) shows that the oil treated with rye flour is significantly inferior in organoleptic and physico-chemical indicators to the oil treated with wheat flour, which indicates its weaker ability to adsorb oil oxidation products. In particular, the relatively higher acid number and optical density of the oil treated with rye flour indicate that rye flour adsorbs to a lesser extent free fatty acids and oxidation products of unsaturated compounds that interact with carotene.

Below in the table. Table 2 shows the results of studies investigating the effect of different amounts of applied flour on the quality of unrefined sunflower oil.

As can be seen from the data table. 2, the original oil, which had a musty smell and a taste of pronounced bitterness, after processing at a ratio of flour and oil equal to 1:10, acquires a fairly pure taste and smell characteristic of unrefined sunflower oil. At the same time, its acid number, optical density, refractive index and oil oxidation decrease. This indicates flour adsorption of oxidation products such as free fatty acids and carotene-containing unsaturated compounds formed during the oxidation of an oil (hydrocarbons, ketones, hydroxy ketones, etc.), which contributes to an increase in the quality of the oil. The increase in the amount of flour added to the oil (1: 9, 1: 8, 1: 5), although it helps to reduce the taste and smell of oil, but does not allow to obtain oil of the required quality, which, apparently, is due to oxidation of unsaturated compounds with oxygen entering the oil with the introduction of large quantities of porous adsorbent. A decrease in the amount of flour introduced into the oil (1:11, 1:12, 1:15) leads to the appearance of an unclean taste and an increase in the oxidation capacity of the oil compared with the processing of the product in the ratio of flour and oil equal to 1:10. The reason for this may be an insufficient amount of adsorbent for optimal extraction of oxidation products from the oil.

Thus, the optimum ratio for treating flour with oil is 1:10.

The stirring time of the mixture was established experimentally (see Table 3). As can be seen from the data table. 3, the best results were obtained by mixing the oil with flour for 15-20 minutes.

The essence of the method is as follows.

In unrefined sunflower oil, oxidized during storage, at room temperature, wheat flour in a flour-to-oil ratio of 1:10 is introduced as an adsorbent of oxidation products with continuous stirring. Then, the resulting mixture is thoroughly mixed for 15–20 min, after which the adsorbent is separated by one of the known methods, for example, by centrifugation.

Original oxidized oil with a musty odor and pronounced bitterness, with an acid number of 1.52 mg KOH, oxidation

0.865 and an optical density of 0.360 after the proposed treatment acquires the smell and taste characteristic of fresh, unrefined sunflower oil,

acid number 0.81-0.90 mg KOH, oxidation 0.170-0.178, optical density 0.345-0.348.

PRI me R 1. In 100 kg of unrefined sunflower oil of reduced quality, in particular with a musty smell and pronounced bitterness, with an acid number of 1.52 mg KOH, an oxidation of 0.865, an optical density of 0.360 and a refractive index of 1.4720, at room temperature

at a temperature of 18 ° C, 10 kg of 2nd grade flour are introduced with continuous stirring. The resulting mixture was thoroughly mixed for 15 minutes, after which the flour was separated by centrifugation.

The purified oil has a taste and smell peculiar to unrefined sunflower oil without off-tastes, its acid number is 0.90 mg KOH, oxidation 0.172, optical density

0.348, the refractive index of 1.4710.

Example 2. In unrefined sunflower oil of the same quality as in example 1, at room temperature 20 ° C, add 10 kg of flour of the 2nd grade with continuous stirring. The resulting mixture

mix thoroughly for 18 minutes

the flour is then separated by centrifugation.

The purified oil has a clean smell and

a slight taste of vegetable oil, its acid number is 0.83 mg KOH, oxidation 0.170, optical density 0.345, refractive index 1.4705.

Example 3. In unrefined sunflower oil of the same quality as in example 1, at room temperature 22 ° C, 10 kg of 2nd grade flour are introduced with continuous stirring. The resulting mixture is thoroughly stirred for 20 minutes, then the flour is separated by centrifugation.

Refined oil has a clean smell and a slight taste of vegetable oil. Its acid number is 0.81 mg KOH, oxidation 0.178, optical density 0.345, refractive index 1.4705.

The results of the processing of oxidized unrefined sunflower oil by known and proposed methods are given in Table. four.

0

five

Claims (1)

The proposed method allows to improve the quality of unrefined sunflower oil, oxidized during storage, due to the greater removal of oxidation products from it, in particular free fatty acids, by 1.3 times while reducing oxidation by 1.97 times compared with the known method. DETAILED DESCRIPTION OF THE INVENTION A method for purifying unrefined sunflower oil from oxidation products, including their adsorption on a sorbent and separating a sorbent, characterized in that, in order to more completely remove oxidation products, wheat flour is used as an adsorbent with a 1:10 ratio of flour and oil , and adsorption is carried out by stirring for 15-20 minutes. 20 Table 1 Table 2 Continuation of table 2 Table 3 Table 4