RU2562522C1 - Essential mustard oil production method - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: essential mustard oil production method involves moistening of mustard press cake under stirring and heating conditions, thioglucoside hydrolysis at heating temperature, vacuumisation for formation of a steam phase with the latter delivery for condensation and division; the mustard press cake is preliminarily milled and heated; moistening is performed by way of spraying with water solution heated up to 60-70°C; such solution contains ascorbic acid and culinary salt, the ratio of water:ascorbic acid to culinary salt being 400:1; the ratio of ascorbic acid to culinary salt being 1:4; the weight ratio of press cake to water being 2.7:1; simultaneous treatment of the reaction mass with ultrasonic sound is performed during 5-10 minutes; hydrolysis is performed during 30-35 minutes under excessive pressure equal to 1.2 atm; in the course of vacuumisation treatment with ultrasonic sound is repeated.

EFFECT: invention allows to increase allyl isothiocyanate yield, reduce formation of by-product compounds and decrease liquid wastes quantity.

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Description

The invention relates to the food industry.

Essential mustard oil is a mixture of the products of enzymatic hydrolysis of thioglucosides contained in mustard cake, which was obtained by pressing mustard oil seeds after separating the mustard oil.

The reaction of hydrolysis of thioglucosides in oilcake, depending on the pH of the medium, can proceed in 2 directions: with the formation of allyl isothiocyanate (AITC) or nitriles and their derivatives having high toxicity (for example, cyanepitioalkanes).

A known method of producing isothiocyanates, in which an aqueous suspension is prepared from products of processing mustard oil production in a ratio of 1: 6. The prepared suspension is subjected to extraction at a water temperature of 75-90 ° C, for 30 minutes, then the phases are separated. The solid phase is washed with water and at a water temperature of 40-60 ° C, enzymatic hydrolysis of the thioglucosides contained in the liquid phase is carried out, followed by hot steam treatment to obtain isothiocyanates (see the description of the patent of the Russian Federation No. 2196811, IPC СВВ 13/00, 2002).

The known method is long and energy-consuming due to the presence of a significant amount of water for the extraction and washing of the solid phase, as well as the use of hot steam for steaming the resulting allyl isocyanate. After extraction of the hydrolysis products of thiocyanates with direct steam, a large amount of liquid waste (waste water) is formed containing the residual amount of hydrolysis products, including allyl isothiocyanate.

A known method for producing isothiocyanates, including the preparation of an aqueous suspension of solid by-products of mustard and oil production, taken in relation to water 1:10, subsequent hydrolysis with heating the suspension to a temperature of 45-50 ° C and aging, processing the suspension with hot steam, condensation and separation with water (see the description of the patent of the Russian Federation No. 2196812, IPC C11B 13/00, 2002).

The known method is long, expensive and energy-consuming due to the presence of a significant amount of water for the extraction and washing of the solid phase, as well as the use of hot steam for steaming the resulting allyl isotiocate. In addition, after the extraction of thiocyanate hydrolysis products with hot steam, a large amount of liquid waste (waste water) is formed containing the residual amount of hydrolysis products, including allyl isothiocyanate.

A known method of producing isothiocyanates, adopted as a prototype, comprising hydration of solid by-products of mustard and oil mill production, heating, holding at a heating temperature, evacuation to form a vapor phase with the latter being fed for condensation and separation (see the description of the invention to RF patent No. 2346980, IPC C11B 13/00, published on 02.20.2007).

In the known method, the humidification is carried out in a hydrolyzer-dryer with water with the formation of a dispersed system with stirring, which requires an increased water content and subsequently a significant amount of energy during drying. In addition, insufficient wetting of the reaction mass at the beginning of the process of hydrolysis of thioglucosides, the absence of a catalyst and unregulated pH of the medium significantly reduces the yield of the finished product and increases the degree of contamination by reaction by-products (nitriles, etc.).

The objective and technical result of the proposed method is to increase the yield of allyl isothiocyanate (AITC), cheaper the process, reduce the formation of side compounds and reduce the amount of liquid waste (wastewater).

The technical result is achieved by the fact that in the method for producing essential mustard oil, which includes moisturizing mustard cake with stirring and heating, hydrolysis of thioglucosides at a heating temperature, evacuation to form a vapor phase with the latter being fed for condensation and separation, there are differences, namely, mustard cake is pre-crushed and heated, hydration is carried out by spraying with an aqueous solution containing ascorbic acid and sodium chloride heated to a temperature of 60-70 ° C, in the ratio water: (ascorbic acid and sodium chloride) equal to 400: 1, while the ratio of ascorbic acid to sodium chloride is 1: 4, with a weight ratio of oilcake to water equal to 2.7: 1, while the reaction mass is treated with ultrasound for 5-10 minutes, hydrolysis is carried out for 30-35 minutes at an overpressure of 1.2 atm; under vacuum, the sonication is repeated.

To obtain essential mustard oil with an AITC content of up to 97%, it is proposed to hydrolyse mustard cake thioglucosides with an aqueous solution containing sodium chloride (NaCl), using weak solutions of ascorbic acid as a catalyst.

The proposed method allows to increase the yield of AITC, reduce the formation of side compounds (nitriles, their derivatives, cyanepitioalkanes, etc.), significantly reduce the hydrolysis time, i.e. significantly reduce energy costs, while we obtain essential mustard oil with AITC content up to 97%, using a weak isotonic solution of sodium chloride and catalyst for the hydrolysis of mustard cake thioglucosides, as well as neutralized cake as a feed product.

The use of ultrasound for the hydrolysis process allowed:

- reduce the time of wetting of the reaction mass, thereby drastically reduce the time of hydrolysis;

- reduce the time the temperature affects the enzymatic component of the reaction mass;

to reduce the time of the process of distillation of the vapor-air mixture of hydrolysis products;

- reduce energy consumption due to a significant reduction in the time of the hydrolysis process (up to 1 hour).

The method of obtaining essential mustard oil is as follows.

An aqueous solution containing sodium chloride and ascorbic acid is preliminarily prepared to create the conditions for hydrolysis in a minimum time with a minimum and sufficient water content and in order to obtain high-quality essential oil and waste in the form of a feed product in a dry loose state. It meets these conditions - the ratio of ascorbic acid and sodium chloride is 1: 4; and the ratio of water to (ascorbic acid and sodium chloride) 400: 1, with a weight ratio of oilcake to water, equal to 2.7: 1.

Heated crushed cake is fed into a hydrolyzer preheated with a water jacket. The temperature of the water in the jacket is kept constant for the entire period of the hydrolysis and drying process.

After loading the cake, the loading hatch of the hydrolyzer is closed and an aqueous solution of sodium chloride and ascorbic acid preheated to a temperature of 70 ° C is fed by spraying. Simultaneously with the water supply, the contents of the hydrolyzer are mixed and sonicated with 600VA (vibration intensity not less than 140 dB) for 5-10 minutes during the wetting of the cake. Due to the supply of water, the pressure in the hydrolyzer increases to 1.2 atm. Then the ultrasound is turned off, and within 30-35 minutes hydrolysis occurs at a pressure of 1.2 atm.

After hydrolysis is complete, the pressure is released, the vacuum is turned on, and ultrasound is simultaneously turned on for 5-10 minutes. The drying process under vacuum is carried out for 15 minutes. The carried-off steam-ether mixture is sent to the recovery system: a mechanical filter and a refrigerator, and the dried neutralized cake is discharged for further packaging in consumer packaging.

Example

Heated to 50 ° C, crushed cake to 0.6-0.8 mm in the amount of 800 kg is fed to the hydrolyzer, preheated with a water jacket to a temperature of 50 ° C.

The loading of the hydrolyzer cake is carried out within 1-3 minutes.

After loading the cake, the loading hatch of the hydrolyzer is closed and a prepared aqueous solution with a droplet size of 100 microns in an amount of 300 l is heated up to a temperature of 65-70 ° C for 10 minutes.

A pre-prepared aqueous solution contains ascorbic acid in an amount of 150 g and sodium chloride in an amount of 600 g per 800 kg of oilcake.

Wherein

- the ratio of ascorbic acid and sodium chloride is 1: 4;

- the ratio of water to (ascorbic acid + sodium chloride) 400: 1;

- the ratio of oilcake to aqueous solution of 2.7: 1.

Simultaneously with the water supply, the contents of the hydrolyzer are mixed and sonicated with 600VA with an oscillation intensity of at least 140 dB.

Ultrasonic treatment is carried out for 5-10 minutes during the wetting of the meal. Then the sonication is stopped, and within 30-35 minutes there is hydrolysis at an overpressure of 1.2 atm.

After hydrolysis is complete, the pressure is released, the vacuum is turned on, and ultrasound is simultaneously turned on for 5-10 minutes. To obtain the oil, the entrained vapor-air mixture is sent to a recovery system: a mechanical filter and a refrigerator.

Dried, neutralized cake is unloaded for further packaging in consumer packaging.

Changing the ratio of water to (sodium chloride and ascorbic acid) in the direction of increasing the amount of water will lead to a change (decrease) in the concentration of catalysts, enhance the formation of by-products of the hydrolysis reaction, and reduce the amount of allyl isothiocyanate formation.

Changing the ratio of water to (sodium chloride and ascorbic acid) in the direction of decreasing the amount of water will increase the concentration of catalysts, which, in turn, will slightly increase the yield of the target product, but increase economic costs.

Claims (1)

A method of producing an essential mustard oil, including moisturizing mustard cake with stirring and heating, hydrolysis of thioglucosides at a heating temperature, evacuating to form a vapor phase with the latter being fed to condensation and separation, characterized in that the mustard cake is pre-crushed and heated, moistening is carried out by the heated spray method to a temperature of 60-70 ° C with an aqueous solution containing ascorbic acid and sodium chloride, with a ratio of water: ascorbic acid and sodium chloride, equal to ohm 400: 1, while the ratio of ascorbic acid to sodium chloride is 1: 4, with a weight ratio of cake to water equal to 2.7: 1, with simultaneous ultrasonic treatment of the reaction mass for 5-10 minutes, hydrolysis is carried out for 30 -35 minutes at an overpressure of 1.2 atm; under vacuum, the sonication is repeated.