A method for monitoring dissolved oxygen dynamics and identifying oxidation risk in the whole process of specialty berry fermented wine

Abstract

This invention discloses a method for dynamic monitoring of dissolved oxygen and identification of oxidation risks throughout the entire fermentation process of specialty berry wines. For seven berry species—blueberry, raspberry, mulberry, blackberry, black chokeberry, red dragon fruit, and blackcurrant—dissolved oxygen data is systematically collected at 13 key stages, including crushing, fermentation, filtration, fining, aging, cold treatment, and bottling, to create a "dissolved oxygen dynamic spectrum" for each variety. By analyzing the peak dissolved oxygen levels and their rates of change, crushing, fining, cold treatment, and bottling are identified as four high-risk oxidation stages. Furthermore, based on the rate of dissolved oxygen decrease after crushing, the seven berry species are categorized into three types: oxidation buffering, oxidation consuming, and rapid oxygen consuming. This invention achieves a multi-variety, full-chain systematic assessment of oxidation risks, providing a quantitative basis for precise oxidation control in specialty berry wines.

Description

Technical Field

[0001] This invention belongs to the field of fruit wine brewing technology, specifically involving a method for dynamic monitoring of dissolved oxygen and identification of oxidation risk throughout the entire process of fermenting a specialty berry wine. Background Technology

[0002] Blueberries, raspberries, mulberries, blackberries, black chokeberries, red dragon fruit, blackcurrants, and other specialty berries are rich in anthocyanins, polyphenols, and other natural antioxidants, possessing high nutritional and health benefits. In recent years, my country's specialty berry industry has developed rapidly, with fermented wine, as an important direction for deep processing, showing broad market prospects. However, specialty berry fermented wines are highly susceptible to oxidative degradation during processing, leading to anthocyanin degradation, browning, or precipitation, severely impacting product quality and shelf life.

[0003] Dissolved oxygen (DO) is a key factor initiating oxidation, and its variation patterns differ significantly across different varieties and processing stages. Current research on dissolved oxygen in fruit wines largely focuses on single varieties (such as grapes) or single stages (such as fermentation or bottling), lacking systematic dynamic monitoring of dissolved oxygen throughout the entire process from crushing to finished product for different specialty berry varieties. This makes it difficult to comprehensively identify high-risk oxidation stages and to develop targeted oxygen control strategies based on varietal differences. Therefore, developing a method for dynamic dissolved oxygen monitoring and oxidation risk identification covering the entire chain and multiple varieties is of great significance for improving the quality of specialty berry wines. Summary of the Invention

[0004] The present invention aims to provide a method for dynamic monitoring of dissolved oxygen and identification of oxidation risk throughout the entire process of fermentation of specialty berries, in order to solve the problem of the lack of systematic dissolved oxygen monitoring and oxidation risk identification methods for multiple varieties and the entire chain in the existing technology.

[0005] The present invention adopts the following technical solution:

[0006] A method for dynamic monitoring of dissolved oxygen and identification of oxidation risk throughout the entire process of fermenting a specialty berry wine includes the following steps:

[0007] 1. Determine monitoring nodes

[0008] Dissolved oxygen monitoring points were set up at 13 key process nodes throughout the entire process of making specialty berry fermented wine, specifically including:

[0009] (1) Crushing stage: Monitor every 10 minutes within 60 minutes after crushing;

[0010] (2) Fermentation stage: After the oxygen circulation is started in the middle stage of fermentation, the monitoring is carried out every 5 minutes within 30 minutes;

[0011] (3) Plate and frame filter press stage: before and after filter press and within 20 minutes of equipment operation;

[0012] (4) Adhesive application stage: After adding adhesive, measurements are taken every 3 days for a total of 18 days;

[0013] (5) Diatomaceous earth filtration stage: before and after filtration;

[0014] (6) Rotary vacuum filtration stage: before and after filtration;

[0015] (7) Aging stage: Tested monthly for a total of 8 months;

[0016] (8) Transferring stage: before and after transferring;

[0017] (9) Cold treatment stage: Measured once a day for a total of 7 days;

[0018] (10) Paperboard filtration stage: before and after filtration;

[0019] (11) Storage tank stage before bottling: Add sulfur dioxide and let stand for 12 hours;

[0020] (12) Membrane filtration stage: before and after membrane filtration;

[0021] (13) Filling stage: Measurements were taken after bottling and after corking;

[0022] 2. Dissolved oxygen measurement

[0023] A portable dissolved oxygen meter, such as the Thermo Fisher Orion Star A223, was used. Before the measurement, the meter was calibrated with water vapor-saturated air. During the measurement, the probe was inserted 10 cm below the surface of the wine. The reading was recorded after it stabilized. At least three parallel samples were measured at each node, and the average value was taken as the dissolved oxygen value of that node.

[0024] 3. Draw a dynamic spectrum of dissolved oxygen.

[0025] Based on the dissolved oxygen data measured at each node, a dynamic line graph of dissolved oxygen for each product is plotted with the process node sequence as the x-axis and the dissolved oxygen value as the y-axis. At the same time, a heat map of dissolved oxygen value is plotted with the product as the x-axis and the node as the y-axis to visually display the dissolved oxygen distribution.

[0026] 4. Calculate the dissolved oxygen decrease rate and classify the varieties.

[0027] Take the dissolved oxygen values ​​at two time points, 10 minutes and 60 minutes after the breakage, and calculate the rate of decrease in dissolved oxygen:

[0028]

[0029] Based on the rate of decline, the varieties are divided into three categories:

[0030] (1) Oxidation buffer type: the rate of decrease is ≤ 0.31 mg / (L·min), including black chokeberry (0.25 mg / (L·min)), raspberry (0.28 mg / (L·min)) and blackcurrant (0.31 mg / (L·min)), characterized by high antioxidant content and slow decrease of dissolved oxygen;

[0031] (2) Oxidative depletion type: The rate of decrease is between 0.32 mg / (L·min) and 0.37 mg / (L·min), including blueberries (0.32 mg / (L·min)), blackberries (0.37 mg / (L·min)) and mulberries (0.74 mg / (L·min)). Among them, mulberries have a faster rate of decrease, but they have a higher content of antioxidants and are classified into this category.

[0032] (3) Rapid oxygen consumption type: the rate of decrease is ≥ 0.63 mg / (L·min), including red dragon fruit (0.63 mg / (L·min)), characterized by low antioxidant content and rapid decrease of dissolved oxygen.

[0033] 5. Identify high-risk oxidation processes

[0034] By comparing the dissolved oxygen peak values ​​at each node, four high-risk oxidation stages were identified:

[0035] (1) Breakup stage: The dissolved oxygen peak is between 8.5 mg / L and 8.8 mg / L. All varieties show a sharp increase in dissolved oxygen during this stage.

[0036] (2) Gel application stage: After circulation, the dissolved oxygen peak value is between 6.3 mg / L and 6.6 mg / L. The gel application operation introduces a large amount of oxygen;

[0037] (3) Cold treatment stage: The dissolved oxygen peak is between 4.0 mg / L and 4.4 mg / L when the tank is not full. Cooling leads to an increase in gas solubility.

[0038] (4) Filling stage: The dissolved oxygen peak after bottling is between 6.7 mg / L and 7.0 mg / L, and a large amount of oxygen is introduced during the filling process.

[0039] 6. Output risk identification results

[0040] Based on the above analysis, the oxidation sensitivity type and risk level of each variety are output, providing a basis for subsequent oxidation control.

[0041] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:

[0042] (1) This invention is the first to realize dynamic monitoring of dissolved oxygen in the entire process from crushing to finished product of 7 kinds of special berries, covering 13 key nodes, and the data system is comprehensive.

[0043] (2) This invention classifies varieties into three categories based on the rate of dissolved oxygen decrease, revealing the intrinsic mechanism of the difference in oxidation sensitivity among varieties and providing a scientific basis for differentiated oxygen control.

[0044] (3) This invention accurately identifies four high-risk oxidation processes: crushing, gluing, cold treatment, and filling, and clarifies the key directions for process optimization.

[0045] (4) The method of the present invention is simple to operate and the data is reliable. It can be directly applied to fruit wine production enterprises to guide the formulation of oxidation control process parameters. Attached Figure Description

[0046] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0047] Figure 1 This is a roadmap for implementing the present invention.

[0048] Figure 2 This is a graph showing the dynamic changes in dissolved oxygen throughout the entire process of making berry wine, as described in this embodiment of the invention.

[0049] Figure 3 This is a comparison chart of dissolved oxygen changes during the crushing stage of seven types of berries in an embodiment of the present invention.

[0050] Figure 4 This is a comparison chart of dissolved oxygen changes during the fining stage of seven types of berry wines in an embodiment of the present invention.

[0051] Figure 5 This is a comparison chart of dissolved oxygen changes during the cold treatment stage of seven types of berry wines in this embodiment of the invention.

[0052] Figure 6 This is a comparison chart of dissolved oxygen changes during the bottling stage of seven types of berry wines in this embodiment of the invention. Detailed Implementation

[0053] The present invention will be further described below through specific embodiments, but the present invention is not limited to the following embodiments.

[0054] Example 1: Dynamic monitoring of dissolved oxygen and identification of oxidation risk throughout the blueberry wine production process

[0055] 1. Raw materials and equipment

[0056] Ingredients: Frozen blueberries (Southern Highbush, Jiangsu), soluble solids 11.4°Brix.

[0057] Equipment: CG-170 destemming and crushing machine, stainless steel fermentation tank (1 T), plate and frame filter press, diatomaceous earth filter, rotary vacuum filter, paperboard filter, membrane filtration system, bottle filling and capping machine, Thermo Fisher Orion StarA223 portable dissolved oxygen meter.

[0058] 2. Monitoring Nodes and Measurement Methods

[0059] Monitor according to the 13 nodes in step one. When measuring dissolved oxygen, insert the probe 10 cm below the liquid surface, and record the reading after it stabilizes. Record 3 parallel samples for each node.

[0060] 3. Results

[0061] (1) Breakup stage: 10 minutes after breakup, dissolved oxygen was 8.65 mg / L, maintained between 8.53 mg / L and 8.79 mg / L for 30 minutes, dropped sharply to 2.35 mg / L after 40 minutes, and dropped to 0.14 mg / L after 60 minutes. Calculated rate of decrease: (8.65-0.14) / 50 = 0.17 mg / (L·min).

[0062] (2) Fermentation stage: After circulating oxygen, the initial dissolved oxygen was 8.63 mg / L, which dropped to 0.47 mg / L after 30 minutes.

[0063] (3) Plate and frame filter press: dissolved oxygen was 0.58 mg / L before filter press, 2.39 mg / L after filter press, and 4.22 mg / L after the equipment had been running for 5 minutes.

[0064] (4) Gel application stage: Dissolved oxygen was 6.47 mg / L on day 0 after gel application, and decreased to 0.24 mg / L after 18 days.

[0065] (5) Diatomaceous earth filtration: 0.24 mg / L before filtration, 0.78 mg / L after filtration.

[0066] (6) Rotary vacuum filtration: 0.24 mg / L before filtration, 2.86 mg / L after filtration.

[0067] (7) Aging: Initially 0.78 mg / L, after 2 months 0.24 mg / L, after 8 months 0.04 mg / L.

[0068] (8) Refilling: 0.04 mg / L before refilling, 0.28 mg / L after refilling.

[0069] (9) Cold treatment: initial dose 0.28 mg / L, dose 2.54 mg / L after 1 day, and dose 1.86 mg / L after 7 days.

[0070] (10) Paperboard filtration: 1.86 mg / L before filtration, 2.14 mg / L after filtration.

[0071] (11) Storage tank before bottling: initial concentration 3.13 mg / L, 1.26 mg / L after 12 hours.

[0072] (12) Membrane filtration: 1.26 mg / L before membrane filtration and 1.32 mg / L after membrane filtration.

[0073] (13) Filling: 6.73 mg / L after bottling, 6.81 mg / L after stoppering.

[0074] 4. Risk Identification

[0075] If the dissolved oxygen value after a process node is significantly higher than that of its immediate preceding and following process nodes, then that node can be defined as a "peak node" or a "high-risk node".

[0076] By plotting the dynamic change curve of dissolved oxygen throughout the entire process using the above data, nodes where the dissolved oxygen value rises sharply can be visually identified. The dissolved oxygen growth rate of each node is compared with that of the previous node at each process stage, and nodes with a growth rate exceeding 100% are listed as candidates.

[0077] (1) Crushing stage: 10 minutes after the raw material is crushed, the dissolved oxygen level soars to 8.65 mg / L, with an unlimited increase; the dissolved oxygen level at the adjacent subsequent nodes has dropped to 0.47 mg / L, a decrease of more than 94%. The dissolved oxygen level in the crushing stage ranks first among all nodes, forming the highest peak in the entire process.

[0078] (2) Gel application stage: The dissolved oxygen level at the previous node after plate and frame filtration was 2.39 mg / L, and immediately rose to 6.47 mg / L after gel application, an increase of 171%. After the next node after diatomaceous earth filtration, the dissolved oxygen level dropped to 0.78 mg / L, a huge decrease. This node formed a significant local peak.

[0079] (3) Cold treatment stage: Before cold treatment, the dissolved oxygen was only 0.04 mg / L. On the first day of cold treatment, the dissolved oxygen rose to 2.54 mg / L, an increase of more than 800%. After the cold treatment, the dissolved oxygen remained at 1.86 mg / L, which was significantly higher than the level before cold treatment. Although its absolute value was lower than that of crushing and sizing, its relative increase was the largest.

[0080] (4) Filling stage: The dissolved oxygen after filtration at the previous stage was only 1.32 mg / L, but after bottling, the dissolved oxygen suddenly increased to 6.73 mg / L, an increase of 410%. After stoppering, the dissolved oxygen only increased slightly by 0.08 mg / L, indicating that the increase in dissolved oxygen mainly occurred during the bottling process.

[0081] In summary, based on dynamic dissolved oxygen data for blueberry wine, combined with comparisons of process stages and overall trends, crushing, fining, cold treatment, and bottling were identified as four high-risk oxidation stages. Furthermore, based on the rate of oxygen decay, blueberries are determined to be an oxidatively depleted process. Therefore, oxygen control measures should be implemented primarily in the crushing, fining, cold treatment, and bottling stages, and the dosage of antioxidants should be appropriately adjusted according to their oxidative depletion characteristics.

[0082] Example 2: Classification of Oxidative Sensitivity of Seven Types of Berries

[0083] Following the method in Example 1, dissolved oxygen was monitored throughout the entire process for raspberries, mulberries, blackberries, black chokeberries, red dragon fruit, and blackcurrants, and the average dissolved oxygen decrease rate was calculated from 10 to 60 minutes after crushing. The results are shown in Table 1.

[0084]

[0085] According to the classification, oxidative buffer varieties have high polyphenol content and slow dissolved oxygen consumption, requiring enhanced physical oxygen control; while fast oxygen-consuming varieties, such as red-fleshed dragon fruit, have low antioxidant content and fast dissolved oxygen consumption, requiring close attention during the filling process.

[0086] Example: Verification of high-risk processes in trioxide oxidation

[0087] The dissolved oxygen peak values ​​of the seven berries were statistically analyzed, and the results are shown in Table 2.

[0088]

[0089] The dissolved oxygen peak values ​​for all varieties occurred during the four stages of crushing, gluing, cold treatment, and filling, and the peak values ​​were much higher than those at other stages. Therefore, these four stages were identified as high-risk oxidation stages.

[0090] Example 4 Application Effect

[0091] Tianjin Duoji Fruit Wine Engineering Technology Co., Ltd. used the method of this invention to conduct dynamic dissolved oxygen monitoring on the blueberry wine production line. It identified that the dissolved oxygen peak reached 4.2 mg / L during the cold treatment process. Subsequently, nitrogen filling measures were taken to reduce the dissolved oxygen to 1.3 mg / L after cold treatment, and the product's shelf life and quality were significantly improved.

[0092] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for dynamic monitoring of dissolved oxygen and identification of oxidation risk throughout the entire process of fermenting a specialty berry wine, characterized in that, Includes the following steps: (1) Dissolved oxygen monitoring points are set up at 13 key process nodes in the entire process of brewing specialty berry fermented wine. The key process nodes include: crushing, fermentation, plate and frame filter press, fining, diatomaceous earth filtration, rotary vacuum filtration, aging, racking, cold treatment, paperboard filtration, membrane filtration, pre-bottling storage tank and bottling. (2) The dissolved oxygen value of the wine at each node was measured using a dissolved oxygen meter. At least three parallel samples were measured at each node, and the average value was taken to draw a dynamic spectrum of dissolved oxygen for each variety. (3) Based on the rate of dissolved oxygen decrease within 10 to 60 minutes after crushing, the special berries are classified into oxidation buffer type, oxidation consumption type and rapid oxygen consumption type. (4) By comparing the dissolved oxygen peak values ​​at each node, crushing, glue application, cold treatment and filling were identified as four high-risk oxidation stages.

2. The method according to claim 1, characterized in that, The featured berries include one of the following: blueberry, raspberry, mulberry, blackberry, black chokeberry, red dragon fruit, or blackcurrant.

3. The method according to claim 1, characterized in that, The dissolved oxygen was measured using a portable dissolved oxygen meter. The probe was inserted 10 cm below the liquid surface, and the reading was recorded after it stabilized.

4. The method according to claim 1, characterized in that, The method for calculating the dissolved oxygen decrease rate is as follows: take the dissolved oxygen values ​​at two time points, 10 minutes and 60 minutes after the breakage, calculate the difference and divide it by the time interval.

5. The method according to claim 1, characterized in that, The oxidative buffer type refers to varieties with a dissolved oxygen decrease rate ≤ 0.31 mg / (L·min), including black chokeberry, raspberry, and blackcurrant; the oxidative depletion type refers to varieties with a dissolved oxygen decrease rate between 0.32 mg / (L·min) and 0.37 mg / (L·min), including blueberry, blackberry, and mulberry; the rapid oxygen depletion type refers to varieties with a dissolved oxygen decrease rate ≥ 0.63 mg / (L·min), including red dragon fruit.

6. The method according to claim 1, characterized in that, The dissolved oxygen peak values ​​for the four high-risk oxidation stages are as follows: during the crushing stage, the dissolved oxygen peak value is between 8.5 mg / L and 8.8 mg / L; during the sizing stage, the dissolved oxygen peak value is between 6.3 mg / L and 6.6 mg / L; during the cold treatment stage when the tank is not fully filled, the dissolved oxygen peak value is between 4.0 mg / L and 4.4 mg / L; and during the filling stage, the dissolved oxygen peak value is between 6.7 mg / L and 7.0 mg / L.

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