阅读说明：本技术 通过氮气替代部分水蒸气脱臭降低油脂水解率的方法 (Method for reducing hydrolysis rate of grease by deodorizing nitrogen instead of partial steam ) 是由 张理博 罗淑年 袁泰增 于殿宇 焦春刚 欧阳春华 宁春雨 黄传嘉 于 2019-10-21 设计创作，主要内容包括：本发明利用氮气及蒸汽并用的方法来进行脱臭,采用两段式脱臭工艺来对脱色植物油脂进行脱臭处理,通过氮气替代部分水蒸气脱臭降低油脂水解率的方法。传统的脱臭工艺和两段式脱臭工艺选用蒸汽作为汽提气体,含有一定的氧气,油脂会发生水解和氧化,选用氮气费用昂贵。本发明中选用两段式脱臭工艺,在极度真空条件下,在上段填料塔中将油脂加热,相对温度较低的条件下,通入氮气排出塔内以及油脂中的氧气,脱除油脂中的低沸点物质。油脂引出塔外继续加热后引入下段填料塔通入水蒸气脱除高沸点物质。利用通过氮气替代部分水蒸气脱臭降低油脂水解率的方法,既可以降低油脂的水解及氧化又可以降低脱臭工艺的成本,为食品加工安全领域提供了理论指导。(The invention relates to a method for deodorizing by using nitrogen and steam, deodorizing decolored vegetable oil by adopting a two-stage deodorizing process, and deodorizing by using nitrogen to replace partial steam to reduce the hydrolysis rate of the oil. The traditional deodorization process and the two-section deodorization process select steam as stripping gas, contain certain oxygen, the grease can be hydrolyzed and oxidized, and the cost of selecting nitrogen is high. The two-stage deodorization process is adopted, the grease is heated in an upper-stage packed tower under the extreme vacuum condition, and the nitrogen is introduced into the tower to be discharged and the oxygen in the grease is introduced under the condition of relatively low temperature, so that low-boiling-point substances in the grease are removed. The grease is led out of the tower to be heated continuously and then led into a lower section packed tower to be introduced with water vapor to remove high boiling point substances. The method for reducing the hydrolysis rate of the grease by deodorizing the nitrogen instead of part of water vapor can reduce the hydrolysis and oxidation of the grease and the cost of the deodorization process, and provides theoretical guidance for the field of food processing safety.)

1. The method for reducing the hydrolysis rate of the grease by deodorizing nitrogen instead of part of water vapor is realized by the following steps: the method comprises the following steps: introducing a certain amount of decolorized vegetable oil into a double-helix heater, raising the temperature to 160-200 ℃, and feeding into an upper half section of a packed tower; step two: adjusting deodorization time to 8-12 min; step three: introducing nitrogen in an amount of 0.1-0.5%; step four: leading the deodorized vegetable oil out of the tower, heating to 230-260 deg.c, leading the oil into the lower packed tower, and introducing steam for high temperature deodorization; step five: deodorizing for 30-70 min; step six: the steam quantity is 0.3-0.7%, the influence of different deodorization temperatures, deodorization time and ventilation quantity of the upper and lower sections on the hydrolysis rate of the decolored vegetable oil is inspected, and the optimal conditions of different parameters are determined.

2. The method for reducing the hydrolysis rate of fats and oils by deodorization using nitrogen instead of part of water vapor according to claim 1, wherein the deodorization temperature of the packed tower at the upper stage is controlled at 160, 170, 180, 190, 200 ℃ in the first step.

3. The method for reducing the hydrolysis rate of fats and oils by deodorization with nitrogen instead of part of water vapor according to claim 1, wherein the deodorization time of the upper packed tower in the second step is controlled to be 8, 9, 10, 11, 12 min.

4. The method for reducing the hydrolysis rate of grease by deodorizing with nitrogen instead of part of water vapor according to claim 1, characterized in that the nitrogen aeration rate of the upper packed tower in the third step is controlled to be 0.1, 0.2, 0.3, 0.4, 0.5%.

5. The method for reducing the hydrolysis rate of grease by deodorizing with nitrogen instead of part of water vapor according to claim 1, wherein the deodorizing temperature of the packed tower in the fourth, middle and lower sections is controlled at 220, 230, 240, 250, 260 ℃.

6. the method for reducing the hydrolysis rate of grease by deodorizing with nitrogen instead of partial steam according to claim 1, characterized in that the deodorization time of the packed tower in the middle-lower section of step five is controlled at 30, 40, 50, 60, 70 min.

7. The method for reducing the hydrolysis rate of fats and oils by deodorization with nitrogen instead of part of water vapor according to claim 1, wherein the steam aeration rate of the packed tower in the middle and lower stages of step six is controlled to be 0.3, 0.4, 0.5, 0.6, 0.7%.

Technical Field

The invention relates to the field of oil refining, in particular to a method for reducing the hydrolysis rate of vegetable oil by using sectional deodorization.

Background

The vegetable oil is used as edible oil which is important in daily life of people, contains rich nutrient substances and can provide daily required energy for human bodies. Deodorization is often carried out when high-quality oil products are processed, and the deodorization of the oil not only can remove odor components in the oil, improve the smoke point of the oil, improve the flavor of edible oil, but also can effectively improve the safety of the oil.

At present, the main deodorization methods include a conventional steam deodorization process, a nitrogen deodorization process, a steam two-stage deodorization process, and the like. The traditional deodorization process mainly removes non-triglyceride components in the grease by using steam, the heating time of the grease is long under the high-temperature condition, the two-section deodorization process selects the steam as stripping gas, although the retention time of the grease in a high-temperature area is shortened, partial residual oxygen molecules in the steam and the grease still exist, the grease can be hydrolyzed and oxidized, and the cost of all selecting the nitrogen is high.

Disclosure of Invention

The invention adopts a sectional deodorization process, oil is heated in an upper section packed tower under the extreme vacuum condition, and nitrogen is introduced to discharge oxygen in the tower and the oil under the condition of lower relative temperature, so that the hydrolysis and oxidation of the oil are reduced. And (3) after the grease is led out of the tower to be heated continuously, the grease is led into a lower section packed tower to be introduced with steam to be deodorized continuously at high temperature. Nitrogen is respectively utilized to remove low boiling point substances under the condition of low temperature, then steam is introduced under the condition of high temperature, the liquefaction of the steam can be prevented, the contact time of oxygen in the steam and high-temperature grease can be shortened, the cost of a deodorization process is reduced, higher-quality vegetable grease can be obtained, and theoretical guidance is provided for the field of food processing safety.

The specific implementation mode is as follows: