CN-121975577-A - Rapeseed oil closed loop sterilization method based on heat radiation and steam permeation

CN121975577ACN 121975577 ACN121975577 ACN 121975577ACN-121975577-A

Abstract

The invention relates to the technical field of rapeseed oil sterilization, in particular to a rapeseed oil closed loop sterilization method based on heat radiation and steam permeation, which comprises the steps of preheating rapeseed oil, conveying the rapeseed oil to a deodorization tower, and acquiring infrared thermal imaging data, a viscosity data sequence and a temperature data sequence; the method comprises the steps of determining whether preheating treatment is qualified based on a preheating coefficient, determining a degassing strategy based on a viscosity deviation ratio in response to the preheating treatment being qualified, executing the degassing strategy, determining whether the degassing treatment is qualified based on the moisture content and the dissolved oxygen content after the degassing, stripping the rapeseed oil in response to the degassing treatment being qualified and determining whether the bubble state generated by steam is qualified based on a sound pressure fluctuation rate, reducing steam flow in response to the bubble state being unqualified, determining whether the temperature of the rapeseed oil is reduced based on a sound pressure fluctuation rate slope, and carrying out gradient cooling and filtering treatment on the rapeseed oil after the stripping treatment under vacuum protection to obtain the rapeseed oil after the treatment. The invention improves the quality of the rapeseed oil.

Inventors

ZHANG JUNFENG
XUE DAIHAN
ZHANG HONGYU

Assignees

湖北五龙河食品有限公司

Dates

Publication Date: 20260505
Application Date: 20260409

Claims (10)

1. The rapeseed oil closed loop sterilization method based on heat radiation and steam permeation is characterized by comprising the following steps of: Preheating rapeseed oil to be treated by a plate heat exchanger, conveying the rapeseed oil to a deodorizing tower, and acquiring infrared thermal imaging data and viscosity data sequences and temperature data sequences of the rapeseed oil with preset period inner plate heat exchanger outlet sections; Determining a temperature standard deviation value of the rapeseed oil according to the infrared thermal imaging data, determining a viscosity average value of a preset temperature interval based on the viscosity data sequence, and determining a preheating coefficient according to the temperature standard deviation value and the viscosity average value to determine whether the preheating treatment is qualified or not; determining a corresponding instantaneous viscosity value based on a temperature intermediate value of a preset temperature interval of the rapeseed oil to determine a viscosity deviation ratio of the rapeseed oil and a degassing strategy in response to the preheating treatment being qualified; Executing the degassing strategy, and acquiring the moisture content and the dissolved oxygen content of the degassed rapeseed oil to determine whether the degassing treatment reaches the standard or not; Responding to the degassing treatment reaching the standard, heating the rapeseed oil to a preset temperature, introducing steam to perform steam stripping treatment, and obtaining the sound pressure fluctuation rate of steam flow in the steam stripping treatment process to determine whether the bubble state generated by the steam is qualified; And in response to disqualification of the bubble state generated by the steam, determining an adjusting coefficient according to the sound pressure fluctuation rate and a preset sound pressure fluctuation rate to reduce steam flow, determining a sound pressure fluctuation rate slope in a preset window to determine whether to reduce the temperature of the rapeseed oil, and performing gradient cooling and filtering treatment on the rapeseed oil subjected to steam stripping treatment under vacuum protection to obtain the treated rapeseed oil.
2. The rapeseed oil closed loop sterilization method based on heat radiation and steam permeation according to claim 1, wherein the preheating qualification is determined based on a preheating coefficient greater than or equal to a preset preheating coefficient, wherein, The preheating coefficient is determined by the product of the result of the ratio of the temperature standard deviation to the preset temperature standard deviation and the result of the ratio of the viscosity average to the preset viscosity average.
3. The rapeseed oil closed loop sterilization method based on heat radiation and steam permeation according to claim 1, wherein the degassing treatment standard is determined based on a moisture content less than or equal to a preset moisture content and a dissolved oxygen content less than or equal to a preset dissolved oxygen content.
4. The rapeseed oil closed loop sterilization method based on heat radiation and steam permeation according to claim 1, wherein the disqualification of the bubble state generated by steam is determined based on the sound pressure fluctuation rate being larger than a preset sound pressure fluctuation rate.
5. The canola oil closed loop sterilization method based on thermal radiation and steam infiltration according to claim 2, wherein a degassing strategy is determined as a first degassing strategy based on the viscosity deviation ratio being less than or equal to a first viscosity deviation ratio threshold, wherein, The first degassing strategy is to maintain the vacuum degree at 3 mbar-5 mbar, introduce steam with the steam ratio of 0.5% -1.5%, and maintain the rated feed flow rate of 100%.
6. The canola oil closed loop sterilization method based on thermal radiation and steam infiltration of claim 5, wherein a degassing strategy is determined to be a second degassing strategy based on the viscosity deviation ratio being greater than a first viscosity deviation ratio threshold and less than or equal to a second viscosity deviation ratio threshold, wherein, The second degassing strategy is that the vacuum degree is maintained at 3 mbar-5 mbar, steam is introduced at a steam ratio of 0.8% -2.0%, a rotary foam breaker in the deodorizing tower operates at 60% -80% rated power, and 100% rated feed flow is maintained.
7. The canola oil closed loop sterilization method based on thermal radiation and steam infiltration according to claim 6, wherein a degassing strategy is determined to be a third degassing strategy based on the viscosity deviation ratio being greater than a second viscosity deviation ratio threshold, wherein, The third degassing strategy is that the vacuum degree is maintained at 3 mbar-5 mbar, steam is introduced at a steam ratio of 0.8% -2.0%, a rotary foam breaker in the deodorizing tower operates at a rated power of 60% -80%, and when the foam layer is ultrahigh, 1 ppm-5 ppm of food-grade defoaming agent is injected, and the feeding flow is reduced to 75% -85% of the rated flow.
8. The rapeseed oil closed loop sterilization method based on heat radiation and steam permeation according to claim 4, wherein the temperature of the rapeseed oil is determined to be reduced based on the sound pressure fluctuation rate slope being greater than or equal to a preset sound pressure fluctuation rate slope.
9. The rapeseed oil closed loop sterilization method based on heat radiation and steam permeation according to claim 1, wherein the adjustment coefficient is determined by a ratio of a result of a difference between a sound pressure fluctuation rate and a preset sound pressure fluctuation rate to the preset sound pressure fluctuation rate.
10. A closed loop sterilization method for rapeseed oil based on heat radiation and steam permeation according to claim 3, wherein the de-gassing treatment is determined not to be up to standard based on the moisture content being greater than the preset moisture content or the dissolved oxygen content being greater than the preset dissolved oxygen content, and rapeseed oil is transported to a waste oil tank as industrial oil or degradation treatment.

Description

Rapeseed oil closed loop sterilization method based on heat radiation and steam permeation Technical Field The invention relates to the technical field of rapeseed oil sterilization, in particular to a rapeseed oil closed-loop sterilization method based on heat radiation and steam permeation. Background Rapeseed oil is taken as one of main edible vegetable oil in China, and the deodorization and sterilization procedures in the refining process are important to ensure the flavor of oil products and prolong the shelf life. The traditional deodorization technology generally adopts a high-temperature steam stripping method, and direct steam is introduced under vacuum condition to remove free fatty acid, aldehyde ketone peculiar smell substances and microorganisms in oil. However, the existing industrial deodorization technology still has obvious defects in the aspects of dynamic regulation and process perception, so that the quality of products is unstable, the energy consumption is higher, and the method is more prominent in rapeseed oil treatment with stronger heat sensitivity. Firstly, preheating uniformity lacks quantitative monitoring, rapeseed oil needs to be preheated by a plate heat exchanger before entering a deodorization tower, and the traditional method depends on single temperature point monitoring, so that the integral temperature field distribution of oil cannot be reflected, local peroxidation or insufficient preheating is easy to occur, the mass transfer efficiency of subsequent degassing and steam stripping is influenced, and the flavor deterioration of oil products can be possibly caused. Secondly, the adaptability of the degassing procedure is poor, the foam control depends on experience, the content of colloid such as phospholipid in rapeseed oil is easily influenced by raw material batches, the existing degassing process mostly adopts fixed operation parameters, and is difficult to dynamically adjust oil products with different viscosities and foaming tendencies, so that false foam accumulation is easily caused, the degassing is not thorough, even flooding is caused, and the production continuity and safety are influenced. And the steam stripping process lacks real-time feedback and adjustment, the gas bubble state formed by steam in oil directly influences the deodorization mass transfer efficiency, the traditional method relies on manual observation or terminal detection, abnormal gas bubble behaviors cannot be perceived in real time, for example, uneven steam permeation and incomplete deodorization sterilization caused by too many microbubbles and too high foam stability are caused, and energy waste is easily caused by adjustment lag. The Chinese patent publication No. CN116426335A discloses a deodorizing method of rapeseed oil, which comprises the following steps of sequentially carrying out first heat exchange and second heat exchange on the rapeseed oil to be treated, heating by using heat conduction oil to obtain heated oil steam, enabling the heated oil steam to enter a primary deodorizing tower for primary deodorizing treatment, then enter a secondary deodorizing tower for secondary deodorizing treatment to obtain deodorized oil, and finishing deodorizing treatment of the rapeseed oil, wherein water steam is introduced into the primary deodorizing tower and the secondary deodorizing tower. The invention adopts a two-stage deodorization treatment process, can effectively reduce residual deodorization pressure, deodorization steam consumption, deodorization time and deodorization temperature, is favorable for reducing a large amount of energy consumption in the deodorization process, greatly reduces the loss rate of sterols and vitamin E in the deodorized oil due to the reduction of the deodorization temperature and deodorization time, and can effectively avoid the generation of trans-fatty acid and is favorable for capturing and recycling free fatty acid. It follows that the deodorization method of rapeseed oil has the following problems: 1. Although two-stage deodorization is adopted, the self-adaptive parameter adjustment cannot be carried out according to the real-time state of the oil product, such as temperature field distribution, viscosity characteristics and bubble behaviors, so that the capability of the process for coping with raw material fluctuation and process disturbance is insufficient. 2. The problems of uneven heating, abnormal foam, mass transfer decline and the like in the production process cannot be early-warning and immediate correction, and the production efficiency and the product consistency are affected by depending on the post-result inspection. Disclosure of Invention Therefore, the invention provides a rapeseed oil closed loop sterilization method based on heat radiation and steam permeation, which is used for solving the problem of poor production quality of rapeseed oil caused by lack of real-time sensing and dynamic regulation and control on preheati