Special fructose-glucose syrup for oyster sauce production and preparation process thereof

Abstract

The present application relates to starch sugar manufacturing technical field, and disclose a kind of special fructose syrup for oyster sauce production and its preparation process, including the following steps: raw material liquefaction and first enzyme inactivation, starch raw material is slurried, added liquefaction enzyme and is liquefied treatment, then first enzyme inactivation is carried out at conventional enzyme inactivation temperature, high-temperature intensive inactivation, by using the second enzyme inactivation process including high-temperature intensive inactivation step, and the synergic control of material pH and time in ion exchange treatment process, the complete inactivation of enzyme, especially liquefaction enzyme and saccharifying enzyme activity for production can be realized, the process method overcomes the defect that enzyme inactivation is not thorough in general process, ensures that the final prepared fructose syrup product does not contain residual enzyme activity with hydrolysis effect on starch or dextrin.

Description

Technical Field

[0001] This invention relates to the field of starch sugar manufacturing technology, specifically to a special fructose syrup for oyster sauce production and its preparation process. Background Technology

[0002] High-fructose corn syrup is a starch sugar crystal made from plant starch through hydrolysis and isomerization. It is an important sweetener, a colorless viscous liquid with good fluidity at room temperature and no odor. High-fructose corn syrup is mainly composed of glucose and fructose.

[0003] Currently, the high-fructose corn syrup used in oyster sauce production is mainly a general-purpose product. Its preparation process focuses on meeting general physicochemical indicators, but fails to fully consider its suitability in the specific high-salt, medium-temperature, long-term storage system of oyster sauce. Because general-purpose high-fructose corn syrup is prepared using a standard enzymatic starch saccharification process, the existing liquefaction, saccharification, and post-processing procedures cannot guarantee the complete inactivation of residual amylases that hydrolyze starch or dextrin. When such enzyme activity remains in the high-fructose corn syrup, after being added to oyster sauce, under the mild pasteurization conditions and long shelf life of oyster sauce, it will continue to act on the trace amounts of starch or thickener present in the oyster sauce, causing uncontrollable viscosity decrease, thinning, or stratification of the oyster sauce product during storage, seriously affecting product stability and commercial value.

[0004] Therefore, a special fructose syrup for oyster sauce production and its preparation process are proposed to solve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a special fructose syrup for oyster sauce production and its preparation process, solving the problem mentioned in the background art of failing to fully consider its suitability in the specific high-salt, medium-temperature, long-term storage system of oyster sauce.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a special fructose syrup for oyster sauce production and its preparation process, comprising the following steps: Step 1: Raw material liquefaction and primary enzyme inactivation. The starch raw material is slurryed, liquefying enzyme is added and liquefaction is performed, followed by primary enzyme inactivation at the conventional enzyme inactivation temperature. Step 2: High-temperature enhanced inactivation. The liquefied liquid treated in Step 1 is subjected to a second enzyme inactivation. The inactivation temperature is raised to 130-140℃ and maintained at this temperature for 8-15 minutes to achieve deep inactivation of the liquefied enzyme and other residual enzymes. Step 3: Saccharification and ion exchange. Adjust the pH of the liquefied liquid obtained in Step 2 to 4.0-4.5, add saccharifying enzyme to carry out the saccharification reaction, and obtain saccharified liquid. Perform ion exchange treatment on the saccharified liquid. During the ion exchange treatment, control the pH value of the material to be below 3.5 and maintain this pH value for more than 10 minutes to utilize the acidic environment to synergistically inactivate the residual saccharifying enzyme and other enzyme activities. Step 4: Refining and Concentration. The saccharified liquid after Step 3 is filtered, decolorized, and refined by secondary ion exchange to obtain refined sugar solution. Then, the refined sugar solution is evaporated and concentrated. The system is kept clean during the evaporation process to avoid secondary contamination. Finally, a semi-finished product of fructose syrup is obtained. Step 5: pH final adjustment and sterilization treatment. Adjust and stabilize the pH value of the fructose syrup semi-finished product obtained in Step 4 within the range of 3.3-3.8. Then, perform sterile filtration or instantaneous high-temperature sterilization. After the treatment is completed, cool and store under sterile conditions. Step Six: Specialized Packaging. The high-fructose corn syrup processed in Step Five is filled and sealed using dedicated, pre-sterile liquid bags or dedicated tank trucks to complete the preparation of the specialized high-fructose corn syrup.

[0007] Preferably, in step one, the liquefaction conditions are as follows: the amount of liquefying enzyme added is 0.4-0.6L per ton of oven-dried starch, the liquefaction temperature is 100-110℃, the liquefaction time is 60-120 minutes, the conventional temperature for the first enzyme inactivation is 120-128℃, and the maintenance time is 5-10 minutes.

[0008] Preferably, in step two, the temperature for the secondary enzyme inactivation is 130-140℃, and the duration is 8-15 minutes. The secondary enzyme inactivation is carried out in a tubular or plate sterilization device to ensure that the liquefied liquid is heated evenly without dead corners.

[0009] Preferably, in step three, the conditions for the saccharification reaction are as follows: the amount of saccharifying enzyme added is 0.8-1.2L per ton of dry starch, the saccharification temperature is 58-62℃, and the saccharification time is 24-48 hours until the glucose value reaches the required standard. Specifically, controlling the pH value of the material to be below 3.5 during the ion exchange treatment means controlling the pH value of the material between 2.8 and 3.2 for more than 10 minutes.

[0010] Preferably, in step three, the ion exchange treatment includes sequential cation exchange resin treatment and anion exchange resin treatment. pH control is implemented from the cation exchange stage to ensure that all materials in the ion exchange system experience the acidic low pH environment.

[0011] Preferably, in step four, the evaporation and concentration process uses a multi-effect evaporator, with the evaporation temperature controlled at 60-80℃. After evaporation, the dry matter concentration of the syrup reaches 70-77%. Aseptic operation procedures are adopted during the feeding, unloading, cleaning, and maintenance processes of the evaporation and concentration process to prevent the introduction of heat-resistant bacteria, especially Bacillus.

[0012] Preferably, in step five, the pH adjustment and stabilization control specifically involves: precisely adjusting the pH of the fructose syrup semi-finished product to 3.5±0.1 by adding a food-grade acidity regulator, and maintaining this pH value stable in all subsequent storage and transfer processes; the aseptic filtration uses a sterilizing filter with a pore size of 0.22 microns, or the instantaneous high-temperature sterilization is performed at 135-140℃ for 4-6 seconds.

[0013] Preferably, in step six, the dedicated liquid bag or tank truck needs to undergo a cleaning and sterilization process before use. The sterilization process includes high-temperature steam sterilization or circulating cleaning with food-grade disinfectant, and passing microbial testing. The filling is carried out in a closed environment where the air is purified by a high-efficiency filter.

[0014] Preferably, the process further includes a whole-process microbial monitoring step, setting key control points at the outlet of step two and step four, after the treatment of step five, and before filling of step six, to detect the total number of thermoresistant bacteria, the number of spores, and the residual amylase activity of the syrup sample, ensuring that the total number of thermoresistant bacteria in the final product is less than 10 CFU / g, the number of spores is less than 1 CFU / g, and the residual amylase activity is zero.

[0015] Preferably, the fructose content of the fructose syrup is FF55, its pH value is 3.3-3.8, and the residual enzyme activity of the liquefying amylase and saccharifying amylase that have a hydrolytic effect on starch is zero.

[0016] Compared with the prior art, the present invention provides a special fructose syrup for oyster sauce production and its preparation process, which has the following beneficial effects: 1. In this invention, during the preparation of fructose syrup, a two-stage enzyme inactivation process including a high-temperature enhanced inactivation step, and coordinated control of the pH and time of the material during ion exchange treatment, can achieve complete inactivation of the enzymes used in production, especially liquefying enzymes and saccharifying enzymes. This process overcomes the defect of incomplete enzyme inactivation in general processes, ensuring that the final fructose syrup product does not contain residual enzyme activity that hydrolyzes starch or dextrin. When this special fructose syrup is used in oyster sauce production, it can reduce the problems of decreased viscosity, thinning, or system instability of oyster sauce products caused by the slow action of residual enzymes during oyster sauce storage, thereby improving the shelf-life stability and quality consistency of oyster sauce products.

[0017] 2. In this invention, during the refining and subsequent processing of fructose syrup, a complete microbial barrier system is constructed by implementing clean control during the evaporation and concentration process, strictly aseptically treating the semi-finished fructose syrup and operating under aseptic conditions, and finally filling it with a special packaging container that has undergone pre-sterile treatment. This system can effectively kill and block the contamination and secondary growth of heat-resistant bacteria, especially their spores, thereby reducing the microbial load of the special fructose syrup product. Using this fructose syrup in oyster sauce production can reduce the risk of gas production, rancidity, or biological instability in oyster sauce during later storage due to the introduction of heat-resistant microorganisms from sweetener raw materials, thus ensuring the safety and long-term storage quality of oyster sauce products.

[0018] 3. In this invention, during the final processing of high-fructose corn syrup production, a final pH adjustment step is added to precisely stabilize the pH value of the product within a specific range. This ensures that the acid-base properties of the special high-fructose corn syrup are highly compatible with the oyster sauce product system. This precise pH control reduces pH fluctuations in the oyster sauce system caused by the addition of general-purpose high-fructose corn syrup, ensuring the inherent flavor and taste harmony of the oyster sauce, the stability of its characteristic color, and the normal functioning of the overall preservative system. Therefore, the special high-fructose corn syrup prepared by this invention can be seamlessly integrated into the oyster sauce production system as a highly compatible ingredient, ensuring the stability of the overall quality of the final oyster sauce product. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1: A special fructose syrup for oyster sauce production and its preparation process, comprising the following steps: Step 1: Raw material liquefaction and primary enzyme inactivation. The starch raw material is slurryed, liquefying enzyme is added and liquefaction is performed, followed by primary enzyme inactivation at the conventional enzyme inactivation temperature. Step 2: High-temperature enhanced inactivation. The liquefied liquid treated in Step 1 is subjected to a second enzyme inactivation. The inactivation temperature is raised to 130℃ and maintained at this temperature for 8 minutes to achieve deep inactivation of the liquefied enzyme and other residual enzymes. Step 3: Saccharification and ion exchange. Adjust the pH of the liquefied liquid obtained in Step 2 to 4.0, add saccharifying enzyme to carry out the saccharification reaction, and obtain saccharified liquid. Perform ion exchange treatment on the saccharified liquid. During the ion exchange treatment, control the pH value of the material to be lower than 3.5 and maintain this pH value for more than 10 minutes to utilize the acidic environment to synergistically inactivate the residual saccharifying enzyme and other enzyme activities. Step 4: Refining and Concentration. The saccharified liquid after Step 3 is filtered, decolorized, and refined by secondary ion exchange to obtain refined sugar solution. Then, the refined sugar solution is evaporated and concentrated. The system is kept clean during the evaporation process to avoid secondary contamination. Finally, a semi-finished product of fructose syrup is obtained. Step 5: pH final adjustment and sterilization treatment. Adjust and stabilize the pH value of the fructose syrup semi-finished product obtained in Step 4 at 3.3, and then perform sterile filtration or instantaneous high temperature sterilization. After the treatment is completed, cool and store under sterile conditions. Step Six: Specialized Packaging. The high-fructose corn syrup processed in Step Five is filled and sealed using dedicated, pre-sterile liquid bags or dedicated tank trucks to complete the preparation of the specialized high-fructose corn syrup.

[0021] In step one, the liquefaction conditions are as follows: the amount of liquefying enzyme added is 0.4L per ton of oven-dry starch, the liquefaction temperature is 100℃, the liquefaction time is 60 minutes, the conventional temperature for one enzyme inactivation is 120℃, and the holding time is 5 minutes.

[0022] In step two, the temperature for the secondary enzyme inactivation is 130℃, and the duration is 8 minutes. The secondary enzyme inactivation is carried out in a tubular or plate sterilization device to ensure that the liquefied liquid is heated evenly and without dead corners.

[0023] In step three, the conditions for the saccharification reaction are as follows: the amount of saccharifying enzyme added is 0.8L per ton of dry starch, the saccharification temperature is 58℃, the saccharification time is 24 hours, until the glucose value reaches the required standard, and the pH value of the material is controlled to be below 3.5 during the ion exchange treatment, which specifically means controlling the pH value of the material to be between 2.8 and 2.8 for more than 10 minutes.

[0024] In step three, the ion exchange treatment includes sequential cation exchange resin treatment and anion exchange resin treatment. pH control is implemented at the cation exchange stage to ensure that all materials in the ion exchange system experience an acidic, low-pH environment.

[0025] In step four, a multi-effect evaporator is used for evaporation and concentration, and the evaporation temperature is controlled at 60℃. After evaporation, the dry matter concentration of the syrup reaches 70%. Aseptic operation procedures are adopted in the feeding, unloading, cleaning and maintenance processes of the evaporation and concentration process to prevent the introduction of heat-resistant bacteria, especially Bacillus.

[0026] In step five, pH adjustment and stabilization control specifically involves: precisely adjusting the pH of the fructose syrup semi-finished product to 3.5±0.1 by adding a food-grade acidity regulator, and maintaining this pH value stable in all subsequent storage and transfer processes; aseptic filtration using a sterilizing filter with a pore size of 0.22 microns, or instantaneous high-temperature sterilization at 135°C for 4 seconds.

[0027] In step six, the dedicated liquid bags or tank trucks must undergo cleaning and sterilization procedures before use. The sterilization process includes high-temperature steam sterilization or circulating cleaning with food-grade disinfectant, and passing microbiological testing. The filling is then carried out in a closed environment where the air is purified by a high-efficiency filter.

[0028] The process also includes a full-process microbial monitoring step. Key control points are set at the outlet of step two and step four, after the treatment of step five, and before filling of step six. The total number of heat-resistant bacteria, the number of spores, and the residual amylase activity of the syrup samples are tested to ensure that the total number of heat-resistant bacteria in the final product is less than 10 CFU / g, the number of spores is less than 1 CFU / g, and the residual amylase activity is zero.

[0029] The fructose content of the high-fructose corn syrup is FF55, its pH value is 3.3, and the residual enzyme activity of the liquefying amylase and saccharifying amylase that hydrolyze starch is zero.

[0030] Example 2: A special fructose syrup for oyster sauce production and its preparation process, comprising the following steps: Step 1: Raw material liquefaction and primary enzyme inactivation. The starch raw material is slurryed, liquefying enzyme is added and liquefaction is performed, followed by primary enzyme inactivation at the conventional enzyme inactivation temperature. Step 2: High-temperature enhanced inactivation. The liquefied liquid treated in Step 1 is subjected to a second enzyme inactivation. The inactivation temperature is raised to 135℃ and maintained at this temperature for 11 minutes to achieve deep inactivation of the liquefied enzyme and other residual enzymes. Step 3: Saccharification and ion exchange. Adjust the pH of the liquefied liquid obtained in Step 2 to 4.3, add saccharifying enzyme to carry out the saccharification reaction, and obtain saccharified liquid. Perform ion exchange treatment on the saccharified liquid. During the ion exchange treatment, control the pH value of the material to be lower than 3.5 and maintain this pH value for more than 10 minutes to utilize the acidic environment to synergistically inactivate the residual saccharifying enzyme and other enzyme activities. Step 4: Refining and Concentration. The saccharified liquid after Step 3 is filtered, decolorized, and refined by secondary ion exchange to obtain refined sugar solution. Then, the refined sugar solution is evaporated and concentrated. The system is kept clean during the evaporation process to avoid secondary contamination. Finally, a semi-finished product of fructose syrup is obtained. Step 5: pH final adjustment and sterilization treatment. Adjust and stabilize the pH value of the fructose syrup semi-finished product obtained in Step 4 within the range of 3.5. Then, perform sterile filtration or instantaneous high temperature sterilization treatment. After the treatment is completed, cool and store under sterile conditions. Step Six: Specialized Packaging. The high-fructose corn syrup processed in Step Five is filled and sealed using dedicated, pre-sterile liquid bags or dedicated tank trucks to complete the preparation of the specialized high-fructose corn syrup.

[0031] In step one, the liquefaction conditions are as follows: the amount of liquefying enzyme added is 0.5L per ton of oven-dry starch, the liquefaction temperature is 105℃, the liquefaction time is 90 minutes, the conventional temperature for one enzyme inactivation is 124℃, and the holding time is 7 minutes.

[0032] In step two, the temperature for the secondary enzyme inactivation is 15℃, and the duration is 11 minutes. The secondary enzyme inactivation is carried out in a tubular or plate sterilization device to ensure that the liquefied liquid is heated evenly and without dead corners.

[0033] In step three, the conditions for the saccharification reaction are as follows: the amount of saccharifying enzyme added is 1.0L per ton of dry starch, the saccharification temperature is 60℃, the saccharification time is 36 hours, until the glucose value reaches the required standard. During the ion exchange treatment, the pH value of the material is controlled to be below 3.5, which specifically means controlling the pH value of the material to be between 3.0 and 3.0 for more than 10 minutes.

[0034] In step three, the ion exchange treatment includes sequential cation exchange resin treatment and anion exchange resin treatment. pH control is implemented at the cation exchange stage to ensure that all materials in the ion exchange system experience an acidic, low-pH environment.

[0035] In step four, a multi-effect evaporator is used for evaporation and concentration, and the evaporation temperature is controlled at 70℃. After evaporation, the dry matter concentration of the syrup reaches 73%. Aseptic operation procedures are adopted in the feeding, unloading, cleaning and maintenance processes of the evaporation and concentration process to prevent the introduction of heat-resistant bacteria, especially Bacillus.

[0036] In step five, pH adjustment and stabilization control specifically involves: precisely adjusting the pH of the fructose syrup semi-finished product to 3.5±0.1 by adding a food-grade acidity regulator, and maintaining this pH value stable in all subsequent storage and transfer processes; aseptic filtration using a sterilizing filter with a pore size of 0.22 microns, or instantaneous high-temperature sterilization at 137°C for 5 seconds.

[0037] In step six, the dedicated liquid bags or tank trucks must undergo cleaning and sterilization procedures before use. The sterilization process includes high-temperature steam sterilization or circulating cleaning with food-grade disinfectant, and passing microbiological testing. The filling is then carried out in a closed environment where the air is purified by a high-efficiency filter.

[0038] The process also includes a full-process microbial monitoring step. Key control points are set at the outlet of step two and step four, after the treatment of step five, and before filling of step six. The total number of heat-resistant bacteria, the number of spores, and the residual amylase activity of the syrup samples are tested to ensure that the total number of heat-resistant bacteria in the final product is less than 10 CFU / g, the number of spores is less than 1 CFU / g, and the residual amylase activity is zero.

[0039] The fructose content of the high-fructose corn syrup is FF55, its pH value is 3.5, and the residual enzyme activity of the liquefying amylase and saccharifying amylase that hydrolyze starch is zero.

[0040] Example 3: A special fructose syrup for oyster sauce production and its preparation process, comprising the following steps: Step 1: Raw material liquefaction and primary enzyme inactivation. The starch raw material is slurryed, liquefying enzyme is added and liquefaction is performed, followed by primary enzyme inactivation at the conventional enzyme inactivation temperature. Step 2: High-temperature enhanced inactivation. The liquefied liquid treated in Step 1 is subjected to a second enzyme inactivation. The inactivation temperature is raised to 140℃ and maintained at this temperature for 15 minutes to achieve deep inactivation of the liquefied enzyme and other residual enzymes. Step 3: Saccharification and ion exchange. Adjust the pH of the liquefied liquid obtained in Step 2 to 4.5, add saccharifying enzyme to carry out the saccharification reaction, and obtain saccharified liquid. Perform ion exchange treatment on the saccharified liquid. During the ion exchange treatment, control the pH value of the material to be lower than 3.5 and maintain this pH value for more than 10 minutes to utilize the acidic environment to synergistically inactivate the residual saccharifying enzyme and other enzyme activities. Step 4: Refining and Concentration. The saccharified liquid after Step 3 is filtered, decolorized, and refined by secondary ion exchange to obtain refined sugar solution. Then, the refined sugar solution is evaporated and concentrated. The system is kept clean during the evaporation process to avoid secondary contamination. Finally, a semi-finished product of fructose syrup is obtained. Step 5: pH final adjustment and sterilization treatment. Adjust and stabilize the pH value of the fructose syrup semi-finished product obtained in Step 4 within the range of 3.8. Then, perform sterile filtration or instantaneous high temperature sterilization treatment. After the treatment is completed, cool and store under sterile conditions. Step Six: Specialized Packaging. The high-fructose corn syrup processed in Step Five is filled and sealed using dedicated, pre-sterile liquid bags or dedicated tank trucks to complete the preparation of the specialized high-fructose corn syrup.

[0041] In step one, the liquefaction conditions are as follows: the amount of liquefying enzyme added is 0.6L per ton of oven-dried starch, the liquefaction temperature is 110℃, the liquefaction time is 120 minutes, the conventional temperature for one enzyme inactivation is 128℃, and the holding time is 10 minutes.

[0042] In step two, the temperature for the secondary enzyme inactivation is 140℃, and the duration is 15 minutes. The secondary enzyme inactivation is carried out in a tubular or plate sterilization device to ensure that the liquefied liquid is heated evenly and without dead corners.

[0043] In step three, the conditions for the saccharification reaction are as follows: the amount of saccharifying enzyme added is 1.2L per ton of dry starch, the saccharification temperature is 62℃, the saccharification time is 48 hours, until the glucose value reaches the required standard. During the ion exchange treatment, the pH value of the material is controlled to be below 3.5, which specifically means controlling the pH value of the material between 3.2 and 3.2 for more than 10 minutes.

[0044] In step three, the ion exchange treatment includes sequential cation exchange resin treatment and anion exchange resin treatment. pH control is implemented at the cation exchange stage to ensure that all materials in the ion exchange system experience an acidic, low-pH environment.

[0045] In step four, a multi-effect evaporator is used for evaporation and concentration, and the evaporation temperature is controlled at 80℃. After evaporation, the dry matter concentration of the syrup reaches 77%. Aseptic operation procedures are adopted in the feeding, unloading, cleaning and maintenance processes of the evaporation and concentration process to prevent the introduction of heat-resistant bacteria, especially Bacillus.

[0046] In step five, pH adjustment and stabilization control specifically involves: precisely adjusting the pH of the fructose syrup semi-finished product to 3.5±0.1 by adding a food-grade acidity regulator, and maintaining this pH value stable in all subsequent storage and transfer processes; aseptic filtration using a sterilizing filter with a pore size of 0.22 microns, or instantaneous high-temperature sterilization at 140°C for 6 seconds.

[0047] In step six, the dedicated liquid bags or tank trucks must undergo cleaning and sterilization procedures before use. The sterilization process includes high-temperature steam sterilization or circulating cleaning with food-grade disinfectant, and passing microbiological testing. The filling is then carried out in a closed environment where the air is purified by a high-efficiency filter.

[0048] The process also includes a full-process microbial monitoring step. Key control points are set at the outlet of step two and step four, after the treatment of step five, and before filling of step six. The total number of heat-resistant bacteria, the number of spores, and the residual amylase activity of the syrup samples are tested to ensure that the total number of heat-resistant bacteria in the final product is less than 10 CFU / g, the number of spores is less than 1 CFU / g, and the residual amylase activity is zero.

[0049] The fructose content of the high-fructose corn syrup is FF55, its pH value is 3.8, and the residual enzyme activity of the liquefying amylase and saccharifying amylase that hydrolyze starch is zero.

[0050] Comparative Example 1: The difference between this comparative example and Example 1 is that this comparative example did not undergo the high-temperature enhanced inactivation in step two during preparation, but only underwent one enzyme inactivation at a conventional temperature.

[0051] Comparative Example 2 differs from Example 2 in that: in step three, the material was not kept in a low pH environment during the ion exchange process in this comparative example, and the pH value of the material was maintained above 4.0 throughout the ion exchange process.

[0052] Comparative Example 3 differs from Example 3 in that: this comparative example did not undergo the aseptic treatment in step five, and the syrup was directly cooled and filled after refining and concentration.

[0053] Comparative Example 4 differs from Example 3 in that: in step five, the pH of the fructose syrup semi-finished product was not adjusted, and the final product pH value was the natural pH value after concentration.

[0054] Key performance tests were conducted on the fructose syrups prepared in Examples 1-3 and Comparative Examples 1-4. The test items and methods are as follows: Residual amylase activity test: A spectrophotometric method was used, with soluble starch as the substrate, to react with the sample at 60℃ and pH 4.8. The amount of reducing sugar generated was measured, and the enzyme activity units were calculated to assess the potential enzyme activity risk that could lead to instability in the oyster sauce system.

[0055] Tests for thermostable bacteria and total spore count: After sampling, the sample was heated in an 80°C water bath for 10 minutes to kill the vegetative cells. Then, the plate count method was used, and the sample was incubated in glucose-tryptone agar at 55°C for 48 hours. The colony-forming units were counted to assess the microbial stability of the product.

[0056] pH stability test: The original pH value of the sample was measured using a precision pH meter. The sample was then placed in a 50°C constant temperature chamber for accelerated storage for 30 days. The pH value was measured again, and the absolute value of pH change was calculated to evaluate the acid-base stability of the product.

[0057] Fructose content determination: High performance liquid chromatography was used to ensure that the basic sugar groups of the product met the requirements.

[0058] The test data of the special fructose syrups prepared in Examples 1-3 and Comparative Examples 1-4 are recorded in the table below:

[0059] By comparing and analyzing the data in the table, it can be seen that the special fructose syrup prepared using the process in Examples 1-3 is significantly superior to the fructose syrup prepared using the process in Comparative Examples 1-4 in terms of key performance. This indicates that by adopting a two-stage enzyme inactivation process that includes a high-temperature enhanced inactivation step, and by synergistically controlling the pH and time of the material during ion exchange treatment, it is possible to completely inactivate the enzymes used in production, especially liquefying enzymes and saccharifying enzymes. This process overcomes the defect of incomplete enzyme inactivation in general processes, ensuring that the final fructose syrup product does not contain residual enzyme activity that hydrolyzes starch or dextrin. When this special fructose syrup is used in oyster sauce production, it can reduce the problems of decreased viscosity, thinning, or system instability of oyster sauce products caused by the slow action of residual enzymes during oyster sauce storage, thereby improving the shelf-life stability and quality consistency of oyster sauce products. By implementing clean control during the evaporation and concentration process, strictly aseptically treating the fructose syrup semi-finished product, and operating under aseptic conditions, the final product is made from pre-sterilized... The product is filled using specialized packaging containers, creating a complete microbial barrier system. This system effectively kills and blocks contamination and secondary growth of heat-resistant bacteria, especially their spores, reducing the microbial load of the resulting specialized fructose syrup. Using this fructose syrup in oyster sauce production reduces the risk of gas production, rancidity, or biological instability in oyster sauce during later storage due to the introduction of heat-resistant microorganisms from sweetener raw materials. This ensures the safety and long-term storage quality of the oyster sauce product. By adding a final pH adjustment step and precisely stabilizing the product's pH value within a specific range, the acid-base properties of the specialized fructose syrup are highly compatible with the oyster sauce system. This precise pH control reduces pH fluctuations in the oyster sauce system caused by the addition of general-purpose fructose syrup, ensuring the inherent flavor and taste harmony, characteristic color stability, and the normal functioning of the overall preservative system. Therefore, the specialized fructose syrup prepared by this invention can be seamlessly integrated into the oyster sauce production system as a highly compatible ingredient, ensuring the stability of the final oyster sauce product's overall quality.

[0060] By comparing and analyzing the relevant data in the table, it can be seen that the special fructose syrup prepared by the process of the present invention not only achieves zero residual amylase activity, but also has extremely low microbial risk, precise and stable pH, and excellent compatibility with oyster sauce system. This shows that the special fructose syrup for oyster sauce production and its preparation process provided by the present invention have superior comprehensive performance.

[0061] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0062] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A preparation process for a special high-fructose corn syrup for oyster sauce production, characterized in that, Includes the following steps: Step 1: Raw material liquefaction and primary enzyme inactivation. The starch raw material is slurryed, liquefying enzyme is added and liquefaction is performed, followed by primary enzyme inactivation at the conventional enzyme inactivation temperature. Step 2: High-temperature enhanced inactivation. The liquefied liquid treated in Step 1 is subjected to a second enzyme inactivation. The enzyme inactivation temperature is raised to 130-140℃ and maintained at this temperature for 8-15 minutes. Step 3: Saccharification and ion exchange. Adjust the pH of the liquefied liquid obtained in Step 2 to 4.0-4.5, add saccharifying enzyme to carry out the saccharification reaction, and obtain saccharified liquid. Perform ion exchange treatment on the saccharified liquid. During the ion exchange treatment, control the pH value of the material to be lower than 3.5 and maintain this pH value for more than 10 minutes to utilize the acidic environment to synergistically inactivate the residual saccharifying enzyme and other enzyme activities. Step 4: Refining and Concentration. The saccharified liquid after Step 3 is filtered, decolorized, and refined by secondary ion exchange to obtain refined sugar solution. Then, the refined sugar solution is evaporated and concentrated. The system is kept clean during the evaporation process to avoid secondary contamination. Finally, a semi-finished product of fructose syrup is obtained. Step 5: pH final adjustment and sterilization treatment. Adjust and stabilize the pH value of the fructose syrup semi-finished product obtained in Step 4 within the range of 3.3-3.8, and then perform sterile filtration or instantaneous high temperature sterilization. After the treatment is completed, cool and store under sterile conditions. Step Six: Specialized Packaging. The high-fructose corn syrup processed in Step Five is filled and sealed using dedicated, pre-sterile liquid bags or dedicated tank trucks to complete the preparation of the specialized high-fructose corn syrup.

2. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, In step one, the liquefaction conditions are as follows: the amount of liquefying enzyme added is 0.4-0.6L per ton of oven-dried starch, the liquefaction temperature is 100-110℃, the liquefaction time is 60-120 minutes, and the conventional temperature for the first enzyme inactivation is 120-128℃, with a holding time of 5-10 minutes.

3. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, In step two, the temperature for the secondary enzyme inactivation is 130-140℃, and the duration is 8-15 minutes. The secondary enzyme inactivation is carried out in a tubular or plate sterilization device.

4. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, In step three, the conditions for the saccharification reaction are as follows: the amount of saccharifying enzyme added is 0.8-1.2L per ton of dry starch, the saccharification temperature is 58-62℃, and the saccharification time is 24-48 hours until the glucose value reaches the required standard. The control of the pH value of the material below 3.5 during the ion exchange treatment specifically means controlling the pH value of the material between 2.8 and 3.2 and maintaining it for more than 10 minutes.

5. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, In step three, the ion exchange treatment includes sequential cation exchange resin treatment and anion exchange resin treatment, with pH control implemented during the cation exchange stage.

6. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, In step four, the evaporation and concentration process uses a multi-effect evaporator, with the evaporation temperature controlled at 60-80℃. After evaporation, the dry matter concentration of the syrup reaches 70-77%. Aseptic operation procedures are adopted during the feeding, unloading, cleaning, and maintenance processes of the evaporation and concentration process.

7. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, In step five, the pH adjustment and stabilization control specifically involves: precisely adjusting the pH of the fructose syrup semi-finished product to 3.5±0.1 by adding a food-grade acidity regulator, and maintaining this pH value stable in all subsequent storage and transfer processes; the aseptic filtration uses a sterilizing filter with a pore size of 0.22 microns, or the instantaneous high-temperature sterilization is carried out at 135-140℃ for 4-6 seconds.

8. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, In step six, the dedicated liquid bag or tank truck needs to undergo a cleaning and sterilization process before use. The sterilization process includes high-temperature steam sterilization or circulating cleaning with food-grade disinfectant, and must pass microbial testing. The filling is carried out in a closed environment where the air is purified by a high-efficiency filter.

9. The preparation process of a special fructose syrup for oyster sauce production according to claim 1, characterized in that, The process also includes a full-process microbial monitoring step, setting key control points at the outlet of step two and step four, after processing in step five, and before filling in step six, to detect the total number of thermostable bacteria, the number of spores, and the activity of residual amylase in the syrup samples.

10. A special high-fructose corn syrup for oyster sauce production, prepared by the preparation process of any one of claims 1-9, characterized in that, The fructose content of the fructose syrup is FF55, its pH value is 3.3-3.8, and the residual enzyme activity of the liquefying amylase and saccharifying amylase that hydrolyze starch is zero.

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