Processing method for pickling preserved meat product with assistance of smoking liquid

Abstract

The invention discloses a processing method of a smoked liquid assisted preserved meat product. The processing method comprises the following steps: (1) pretreating raw material meat; (2) uniformly smearing the pickling liquid on the surface of the meat, and then pickling; the pickling liquid comprises edible salt, D-sodium erythorbate, sodium nitrite and a smoking liquid, and the addition amount of the smoking liquid is 3-5% by weight of the meat; the smoking liquid is prepared by the following steps: performing dry distillation fuming on dried wood chips of apricot wood, persimmon wood and pomegranate wood in a mass ratio of (5-8): (2-5): (2-4), condensing and collecting smoke to obtain condensate, and performing post-treatment on the condensate to obtain the smoking liquid. And (3) baking the pickled meat in a constant temperature and humidity chamber. Compared with the traditional smoked duck legs, the smoked duck legs obtained by the invention are safer to eat, the operation is simple while effective flavor substances are increased, the production process is simplified, the processing time is shortened, and the smoked duck legs can be suitable for industrial and standardized production.

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a processing method of smoked liquid assisted cured meat products (especially cured duck legs). Background Art

[0002] Traditional cured duck legs are popular among consumers for their unique smoked flavor, texture and attractive color. However, traditional smoking technology is difficult to adapt to modern industrial-scale production. Liquid smoking has gradually become the development direction of cured duck leg processing instead of traditional gas smoking. Common ways of using liquid smoke include dipping, spraying and injection.

[0003] Liquid smoke contains functional ingredients that are basically the same as smoked tobacco, such as carbonyl compounds, phenolic substances, organic acids, etc., and harmful substances such as tar and polycyclic aromatic hydrocarbons in smoked tobacco have been removed during the production process of liquid smoke, making the product safer. Compared with traditional smoking technology, liquid smoking has a short cycle, requires less equipment, and can achieve continuous and mechanized large-scale production, saving production costs. Liquid smoke of various flavors can better meet the flavor requirements of different products and has a wider range of uses. It can be used to process fish, poultry, eggs and other foods.

[0004] However, the application of liquid smoking technology in the industrial production of cured duck legs has problems such as complex operating procedures, high consumption of smoking liquid, and unstable flavor quality of cured products, which limits the application of liquid smoking technology in the industrial production of cured duck legs. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings and defects mentioned in the above background technology, and provide a processing method for pickling bacon products (especially cured duck legs) assisted by smoked liquid, which significantly improves the quality of bacon, has a simple and safe operation process, stable quality, and is suitable for industrialized and standardized production.

[0006] In order to solve the above technical problems, the technical solution proposed by the present invention is:

[0007] A method for processing bacon products assisted by smoked liquid, comprising the following steps:

[0008] (1) pre-treating the raw meat;

[0009] (2) Apply the marinade evenly on the surface of the meat and then marinate;

[0010] The pickling liquid comprises edible salt, sodium D-isoascorbate, sodium nitrite and smoke liquid, and the amount of the smoke liquid added is 3-5% by weight of the meat;

[0011] The smoke liquid is prepared by the following steps: dry distilling sawdust of dried apricot wood, persimmon wood and pomegranate wood in a mass ratio of (5-8): (2-5): (2-4) to generate smoke, condensing and collecting the smoke to obtain condensate, and post-treating the condensate to obtain the smoke liquid;

[0012] (3) Place the marinated meat in a constant temperature and humidity chamber for baking.

[0013] As a further improvement, the cured meat product is cured duck legs.

[0014] As a further improvement, the apricot wood, persimmon wood and pomegranate wood are crushed to a particle size of 0.3-0.6 cm after drying.

[0015] As a further improvement, the heating rate of the dry distillation in step (2) is >10°C / min, the dry distillation temperature is 650-720°C, and the smoke is collected after 15 minutes of smoke generation.

[0016] As a further improvement, the post-treatment in step (2) includes purification using fruit shell columnar granular activated carbon.

[0017] As a further improvement, the pickling liquid in step (2) includes the following components in percentage by weight of meat: 2.5-4% edible salt, 0.1-0.2% sodium D-isoascorbate, 0.005-0.015% sodium nitrite, and 3-5% liquid smoke.

[0018] As a further improvement, the marinating in step (2) is tumbling and kneading for 3-5 hours.

[0019] As a further improvement, the baking in step (3) adopts high and low temperature cycle baking.

[0020] As a further improvement, the high and low temperature cycle baking: the high temperature baking stage parameters are: 0 to 4 hours, temperature 55°C, relative humidity 70%; the low temperature baking stage parameters are: 4 to 8 hours, temperature 5°C, no humidity limit.

[0021] As a further improvement, the high and low temperature cycle baking time is 4-6 days.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) The composite smoke liquid used in the present invention is derived from apricot wood, persimmon wood, and pomegranate wood. By improving the raw materials for preparing the smoke liquid, the synergistic effect of the flavor in the cured duck legs is achieved, and the color and texture are greatly improved; and the preparation method of the smoke liquid is improved, especially by controlling the wood particle size, heating rate, distillation temperature, and purification method, etc., it is possible to effectively reduce or remove harmful substances such as polycyclic aromatic hydrocarbons formed due to incomplete combustion of the wood and increase effective flavor substances.

[0024] (2) The present invention adopts a smoke liquid-assisted pickling process, and adds smoke liquid in the pickling process of the cured product production process, so that the cured duck legs can absorb enough smoke flavor in a relatively short period of time, making the cured duck legs have uniform flavor quality and good smoke flavor. It can effectively improve the problems of insufficient smoke flavor and uneven quality of liquid-smoked cured duck legs in industrial production. The smoke liquid prepared by the standardized production process can make the quality of cured duck legs more stable and reliable, improve production efficiency, and facilitate large-scale production.

[0025] (3) Compared with the traditional smoking process, the smoked liquid assisted pickling process of the present invention can significantly reduce the content of nitrite in cured duck legs, and can be applied to the processing of cured duck legs. The nitrite content of the cured duck leg sample assisted by smoked liquid is as low as 0.85 mg / kg, which is far lower than the allowable residual amount of nitrite of 30 mg / kg in the sanitary standards for cured meat products in my country. This method can stably and effectively reduce the content of various harmful substances in cured duck legs, especially benzo(a)pyrene, a representative strong carcinogen in smoked cured duck legs. Benzo(a)pyrene was not detected in the liquid smoked cured duck legs produced using this process condition, indicating that the liquid smoked cured duck legs produced by this process are safe to eat.

[0026] (4) The flavor amino acids in the present invention play an important role in the formation of the quality of cured duck legs. During the baking process, the total amount of flavor amino acids in the liquid smoked cured duck legs increased significantly. In the final stage of baking the liquid smoked cured duck legs, the content of alanine, lysine, glutamic acid and serine in the product was significantly higher than that in other stages. The total amount of flavor amino acids in the liquid smoked cured duck legs was significantly higher than that in the traditional smoked duck legs.

[0027] In summary, the smoked cured duck legs obtained by the present invention by improving the preparation and use methods of the smoke liquid are safer to eat than traditional smoked duck legs. While increasing effective flavor substances, the operation is simple, the production process is simplified, the processing time is shortened, and it is suitable for industrialized and standardized production. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 This is the HPLC chromatogram of benzo(a)pyrene of the liquid smoked duck leg sample;

[0030] Figure 2 This is the HPLC chromatogram of 20 ng / mL benzo(a)pyrene standard. DETAILED DESCRIPTION

[0031] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and meticulously below in conjunction with the accompanying drawings and preferred embodiments of the present invention, but the protection scope of the present invention is not limited to the following specific embodiments.

[0032] Unless otherwise defined, all professional terms used below have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention.

[0033] Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0034] In some specific embodiments, the smoke liquid used in the present invention is made from sawdust of apricot wood, persimmon wood and pomegranate wood by dry distillation, wherein the mass ratio of sawdust of apricot wood, persimmon wood and pomegranate wood is (5-8): (2-5): (2-4), preferably 6:4:3. The mass ratio is the mass ratio of sawdust after drying, preferably drying at 100-110° C. for 5-7 hours, more preferably drying at 105° C. for 6 hours. Smoke is generated by dry distillation, and smoke is condensed and collected to obtain condensate, and the condensate is post-processed (including precipitation and stratification, filtration, and purification) to obtain smoke liquid.

[0035] In some embodiments, the dry distillation device is mainly composed of a dry distillation flask, an electric heating jacket with automatic temperature control, a serpentine condenser and a fraction collection device. The method for preparing the smoke liquid comprises the following steps:

[0036] (1) weighing wood and putting it into a dry distillation flask, generating smoke through a dry distillation process, and collecting smoke after the smoke is generated through a serpentine condensation device to obtain a condensate;

[0037] (2) The obtained condensate is subjected to sedimentation and stratification to initially remove the upper oil and the bottom tar, and the middle crude condensate is taken and filtered through a double-layer filter paper for purification.

[0038] Preferably, the wood needs to be air-dried and crushed to a particle size of 0.3-0.6 cm, preferably about 0.5 cm, and the wood chips are dried at 105° C. for 6 hours before use. The change in particle size indirectly affects the heating rate. When the particle size is small (<0.6 cm), it is heated evenly and quickly decomposes to produce phenolic substances during the heating process.

[0039] Preferably, the heating rate of the dry distillation device is >10°C / min, preferably 10-20°C / min, and the dry distillation temperature is 650-720°C, preferably 680°C.

[0040] Preferably, the serpentine condensation device needs to generate smoke for 15 minutes before collecting the smoke.

[0041] By strictly controlling the heating rate, distillation temperature, and smoke collection time, the generation of harmful substances can be reduced and the content of effective substances such as phenols and carbonyl substances can be increased. If the heating rate is too slow and the distillation temperature is too low, the wood will not be completely burned and harmful substances such as polycyclic aromatic hydrocarbons will be formed. If the heating rate is too fast, flavor substances such as phenols will be over-decomposed at high temperatures, reducing the content of flavor substances in the smoke liquid, thereby weakening its antioxidant capacity and unique smoke flavor. If the distillation temperature is too high, more harmful substances will be generated. When the distillation temperature is controlled at 650-720°C, the flavor of the obtained smoke liquid is richer and more diverse. Studies have shown that in the preparation process of hawthorn kernel smoke liquid, the prescribed distillation temperature is 800°C. The present invention preferably uses a distillation temperature of 680°C to distill wood. At the beginning of dry distillation, moisture, air and impurities will be discharged with the initial smoke. After 15 minutes of smoke generation, the reaction system is relatively stable and the components in the smoke also tend to be stable. At this time, the collected smoke can ensure the consistency and stability of the smoke liquid components.

[0042] Preferably, the purification uses food-grade fruit shell columnar granular activated carbon to purify the smoke liquid. Granular carbon can not only adsorb harmful substances well, but also has basically no change in flavor components after adsorption. Therefore, the smoke liquid is purified using food-grade fruit shell columnar granular activated carbon.

[0043] In some specific embodiments, the processing method of the present invention for curing cured meat products (especially cured duck legs) with the aid of smoke liquid comprises the following steps:

[0044] (1) Pretreatment of raw meat:

[0045] Clean and trim the duck legs. Specifically, the raw meat needs to be trimmed and cut into pieces, and excess skin and minced meat need to be removed.

[0046] Then the processed duck legs are air-dried at room temperature (preferably 15-30° C.) to dry the water and then be pickled. Preferably, the room temperature air-drying takes 2 hours.

[0047] (2) Marinating: Place the dried duck legs in a marinating container, apply the marinating liquid evenly on the surface of the meat, and then marinate.

[0048] In some embodiments, the pickling liquid is composed of the following raw materials in percentage by weight of meat: edible salt 2.5-4% (preferably 3.5%), sodium D-isoascorbate 0.1-0.2% (preferably 0.15%), sodium nitrite 0.005-0.015% (preferably 0.01%), and liquid smoke 3-5%. A certain amount of liquor can also be added, and the liquid smoke accounts for 50-70% of the total volume of liquor + liquid smoke, preferably 60%. The preparation method of the pickling liquid is: edible salt, sodium D-isoascorbate, sodium nitrite, and liquid smoke are mixed evenly.

[0049] The smoke liquid assisted pickling method of the present invention is to mix the smoke liquid and the basic pickling agent formula evenly before pickling, which can effectively avoid the problem of complicated operation, the difficulty of the smoke liquid to penetrate into the interior of the food, resulting in poor internal smoking effect and affecting the overall flavor of the product, and avoids the problem of smoke liquid loss in the spraying method and the immersion method.

[0050] In some embodiments, the marinating condition is to place the mixture in a tumbling and kneading machine and marinate for 3-5 hours, preferably 4 hours.

[0051] (3) Baking: After the raw meat is marinated, take it out and put it into a constant temperature and humidity chamber for baking;

[0052] In some embodiments, the baking in the constant temperature and humidity chamber is baking using high and low temperature cycles. The parameters of the high temperature baking stage are: 0 to 4 hours, temperature 55°C, relative humidity 70%, and the parameters of the low temperature baking stage are: 4 to 8 hours, temperature 5°C, and no humidity limit. Baking using high and low temperature cycles makes the dehydration and smoking, which are key to the production of cured duck legs, more thorough.

[0053] In some embodiments, the baking time in the constant temperature and humidity chamber in step 5 is 4-6 days, preferably 5 days.

[0054] The harmful substances described in the present invention are polycyclic aromatic hydrocarbons, which refer to hydrocarbons containing more than two benzene rings, including more than 150 compounds such as naphthalene, anthracene, pyrene, etc., among which 3,4-benzopyrene is the most representative.

[0055] The flavor substances include flavor amino acids and flavor nucleotides, etc. The flavor amino acids are 24 standard amino acids, which are aspartic acid (Asp), glutamic acid (Glu), asparagine (Asn), serine (Ser), glutamine (Gln), histidine (His), glycine (Gly), threonine (Thr), citrulline (Cit), arginine (Arg), alanine (Ala), tyrosine (Tyr), cysteine ​​(Cys), valine (Val), methionine (Met), norvaline (Nva), tryptophan (Trp), phenylalanine (Phe), isoleucine (Ile), lysine (Lys), leucine (Leu), hydroxyproline (Hyp), sarcosine (Sar), and proline (Pro). The synergistic effect of the flavor amino acids and free amino acids together constitutes the characteristic taste of bacon products.

[0056] Example 1

[0057] This embodiment provides a method for preparing liquid-smoked cured duck legs, comprising the following steps:

[0058] Buy frozen duck legs that have passed hygiene inspections and remove excess skin and minced meat;

[0059] The pre-treated duck legs are placed in a marinating container after drying, and 3.5% of the meat weight of edible salt, 0.15% of sodium D-isoascorbate, 0.01% of sodium nitrite, and 4% of smoked liquid are added, mixed evenly, and then applied on the surface of the meat. After the mixture is finished, it is placed in a tumbling machine for tumbling and marinating for 4 hours;

[0060] After the duck legs are marinated, they are taken out and placed in a constant temperature and humidity chamber for baking for 5 days with high and low temperature cycles. The parameters for the high temperature baking stage are: 0-4h, temperature 55°C, relative humidity 70%, and the parameters for the low temperature baking stage are: 4-8h, temperature 5°C, and no humidity limit.

[0061] The liquid smoke used in this embodiment is a mixed liquid smoke made of apricot wood, persimmon wood and pomegranate wood in a mass ratio of 6:4:3 (the sawdust is dried at 105° C. for 6 h). The wood particle size is controlled to be 0.5 cm, the heating rate is 15° C. / min, and the high-temperature dry distillation is performed at 680° C. After fuming for 15 min, the smoke is collected and purified using food-grade fruit shell columnar granular activated carbon to obtain a transparent brown liquid smoke.

[0062] Example 2

[0063] Buy frozen duck legs that have passed hygiene inspections and remove excess skin and minced meat;

[0064] Place the pre-treated duck legs in a marinating container, add 3.5% of the meat weight of edible salt, 0.15% of sodium D-isoascorbate, 0.01% of sodium nitrite, and 4% of smoked liquid, mix well, and apply on the surface of the meat, and then put it into a tumbling machine for tumbling and marinating for 4 hours;

[0065] After the duck legs are marinated, they are taken out and placed in a constant temperature and humidity chamber for baking for 5 days with high and low temperature cycles. The parameters for the high temperature baking stage are: 0-4h, temperature 55°C, relative humidity 70%, and the parameters for the low temperature baking stage are: 4-8h, temperature 5°C, and no humidity limit.

[0066] The liquid smoke used in this embodiment is a mixed liquid smoke made of apricot wood, persimmon wood and pomegranate wood in a mass ratio of 6:2:3 (the sawdust is dried at 105°C for 6h). The wood particle size is controlled to be 0.5cm, the heating rate is 15°C / min, and the high-temperature dry distillation is performed at 680°C. The smoke is collected after fuming for 15min, and the transparent brown liquid smoke is purified using food-grade fruit shell columnar granular activated carbon.

[0067] Comparative Example 1

[0068] In order to verify the effect of the homemade mixed smoke liquid on the quality of cured duck legs, the smoke liquid is commercially available American Red Arrow C10 smoke liquid, which is different from Example 1.

[0069] Comparative Example 2

[0070] In order to verify the effect of high and low temperature cycles on the quality of cured duck legs, this comparative example compares traditional commercially available cured duck legs with liquid smoked cured duck legs obtained by high and low temperature cycles. Unlike Example 1, the smoked cured duck legs are traditional Hunan smoked duck legs that are not smoked by high and low temperature cycles, but are smoked without adding smoke liquid during pickling. After pickling, the smoked duck legs are smoked for 5 days with mixed wood smoke of apricot wood, persimmon wood, and pomegranate wood in a mass ratio of 6:4:3.

[0071] Comparative Example 3

[0072] In order to verify the effect of smoke liquid assisted pickling on the quality of cured duck legs, the smoking method is a spray method different from Example 1. The spray method is to put the pickled duck legs (no smoke liquid is added during pickling) into a constant temperature and humidity chamber for high and low temperature cycle baking for 5 days. During the baking process, the smoke liquid is sprayed twice a day, with each dosage of about 0.20%, and the total dosage is 4%.

[0073] Comparative Example 4

[0074] In order to verify the synergistic effect of the composite smoke liquid, different from the composite smoke liquid in Example 1, the smoke liquid is prepared from only apricot wood.

[0075] Comparative Example 5

[0076] In order to verify the synergistic effect of the composite liquid smoke, the composite liquid smoke is different from the composite liquid smoke in Example 1 in that the composite liquid smoke is prepared using only persimmon wood.

[0077] Comparative Example 6

[0078] In order to verify the synergistic effect of the composite liquid smoke, the composite liquid smoke is different from the composite liquid smoke of Example 1 in that the composite liquid smoke is prepared using only a single wood material, pomegranate wood.

[0079] Test Example 1

[0080] The flavor amino acids in the cured duck leg product samples obtained in Examples 1-3 and Comparative Examples 1-3 were determined by the following detection method:

[0081] (1) Acid hydrolysis (17 types): Weigh 100.0 mg of uniform sample into a sealed bottle, add 10 mL of 6 mol / L hydrochloric acid (containing 1% phenol), fill with nitrogen for 1 min, seal the bottle, and hydrolyze at 110°C for 22 hours. Take out and cool, dilute with water to 50 mL, take 1 mL and evaporate to dryness with nitrogen at 95°C, accurately add 1 mL of 0.01M HCl to dissolve, and measure by membrane.

[0082] (2) Alkaline hydrolysis (tryptophan determination): weigh 0.05-0.2g of powdered sample into a sealed bottle, add 5mL of 5M sodium hydroxide, hydrolyze at 110℃ for 20h, take out and cool, add water to make up to 10mL. Take 2ml, adjust the pH to 7-8 with 2.5M hydrochloric acid (do not over-acidify during the adjustment process), make up to 5mL, filter through a 0.2um water filter membrane, and analyze on an analyzer.

[0083] (3) Determination of flavor amino acids: Grind the sample, weigh 1 g (accurate to 0.001 g) of the wet sample into a 10 mL centrifuge tube, add 5 mL of 0.01 M hydrochloric acid (or pure water), mix well, boil in a boiling water bath for 30 min, and centrifuge at 10,000 rpm for 10 min; take the supernatant, add 4 mL of 0.01 M hydrochloric acid to the precipitate, suspend it, and sonicate for 5 min. Centrifuge, combine the supernatants, make up to 10 mL, and pass through a membrane for determination.

[0084] (4) Detection conditions: Agilent's automatic online derivatization method was used, and derivatization was followed by column detection; chromatographic conditions: ZORBAX Eclipse AAA (4.6 x 150 mm, 3.5 μm); detection signal: UV 338 nm (0-19 min), 266 nm (19.01-25 min); mobile phase A was 40 mM phosphate buffer (pH 7.8), and mobile phase B was acetonitrile: methanol: water = 45:45:10; the flow rate was set to 1.0 mL / min; the elution program used a gradient elution, starting with 100% mobile phase A for 22 min, then 43% mobile phase A and 57% mobile phase B for 4 min, then 100% mobile phase B for 13 min, and finally 100% mobile phase A for 2 min, and the test program ended.

[0085] The specific experimental results are shown in Table 1 (unit: mg / 100g).

[0086] Table 1

[0087]

[0088]

[0089] As can be seen from Table 1, compared with comparative examples 1-3, in Examples 1-2, the contents of total free amino acids and main flavor amino acids in the cured duck legs were significantly increased (P<0.05), indicating that the homemade composite smoke liquid had rich flavor, and high and low temperature circulation and smoke liquid-assisted pickling method played an important role in the formation of good flavor of smoked cured duck legs. Compared with comparative examples 4-6, the contents of total free amino acids and main flavor amino acids in Example 1 were significantly increased (P<0.05), indicating that the synergistic enhancement of the flavor of the composite smoke liquid in the cured duck legs was significantly better than that of the single smoke liquid.

[0090] Test Example 2

[0091] The benzopyrene content in the cured duck leg sample obtained in Example 1 was measured, and the detection method was as follows:

[0092] (1) Pretreatment: Remove the bones from the meat, mince the edible part evenly, store it in a clean sample bottle, mark it, and store it in a refrigerator at -16℃ to -18℃ for later use.

[0093] (2) Extraction: Weigh 1 g (accurate to 0.001 g) of sample, add 5 mL of n-hexane, vortex mix for 0.5 min, ultrasonically extract at 40°C for 10 min, centrifuge at 4000 r / min for 5 min, and transfer the supernatant. Add 5 mL of n-hexane and repeat the extraction. Combine the supernatants and purify them using one of the following two purification methods.

[0094] (3) Purification method 1: Use a neutral alumina column and activate the column with 30 mL of n-hexane. When the liquid level drops to the column bed, close the bottom stopcock. Transfer the liquid to be purified into the column, open the stopcock, collect the purified liquid into an eggplant-shaped bottle at a rate of 1 mL / min, and then transfer 50 mL of n-hexane for elution, and continue to collect the purified liquid. Rotate the purified liquid at 40°C to about 1 mL, transfer it to a chromatograph injection vial, and concentrate it to near dryness under a nitrogen flow at 40°C. Wash the eggplant-shaped bottle with 1 mL of n-hexane, transfer the washing liquid to the chromatograph injection vial again and concentrate it to dryness. Accurately pipette 1 mL of acetonitrile into the chromatograph injection vial, vortex and re-dissolve for 0.5 min, and pass it through a microporous filter membrane for liquid chromatography determination.

[0095] Purification method 2: Use benzo(a)pyrene molecular imprinting column, activate the column with 5mL dichloromethane and 5mL n-hexane in turn. Transfer the liquid to be purified into the column, and when the liquid level drops to the column bed, elute the column with 6mL n-hexane and discard the effluent. Elute with 6mL dichloromethane and collect the purified liquid into a test tube. Dry the purified liquid with nitrogen at 40℃, accurately draw 1mL acetonitrile and vortex to dissolve for 0.5min, and pass it through a microporous filter membrane for liquid chromatography determination.

[0096] (4) The HPLC detection column was an X-Bridge C18 column (column length 250 mm, inner diameter 4.6 mm, particle size 5 μm, or equivalent); mobile phase: acetonitrile + water = 88 + 12; flow rate: 1.0 mL / min; fluorescence detector: excitation wavelength 384 nm, emission wavelength 406 nm; column temperature: 35 °C; injection volume: 20 μL.

[0097] (4) Inject the sample solution for determination and obtain the chromatographic peak area of ​​benzo(a)pyrene. Calculate the concentration of benzo(a)pyrene in the sample solution according to the regression equation of the standard curve.

[0098] The specific experimental results are as follows Figure 1 and Figure 2 As shown, Figure 1 For the smoked duck leg sample, Figure 2 Benzo(a)pyrene 20ng / mL standard. As shown in the figure, no benzo(a)pyrene was detected in the smoke liquid.

[0099] Test Example 3

[0100] This experimental example involves the liquid smoked cured duck legs and traditional smoked cured duck legs in the embodiments and comparative examples, and the sensory quality of the cured duck legs is mainly determined by the expert sensory evaluation method. The reference standard for the sensory score of cured duck legs is shown in Table 2, and the influence on the sensory score of cured duck legs is shown in Table 3.

[0101] Table 2

[0102]

[0103] Table 3

[0104]

[0105] As can be seen from Table 3, the cured duck legs prepared in Example 1-2 have a strong smoky flavor, attractive color, good taste and texture, and show good characteristics in color, smoky flavor, taste and tissue state, indicating that the cured duck legs processed by the present invention not only have good sensory properties, but also have stable quality.

[0106] Test Example 4

[0107] This experimental example involves the detection of color and texture characteristics of the liquid-smoked cured duck leg products and the traditional smoked cured duck legs in the embodiments and comparative examples. The detection values ​​of color and texture characteristics of the cured duck legs are shown in Table 4.

[0108] The color and texture characteristics of the cured duck leg product samples obtained in Examples 1-2 and Comparative Examples 1-6 were determined by the following detection method:

[0109] (1) Determination of color difference: The color difference between the fat and lean parts of bacon was measured by a colorimeter. After the colorimeter was calibrated in black and white (calibration parameters: L* value, a* value and b* value were 91.51, -1.20 and 1.89 respectively), it was measured with a D65 light source at an angle of 10°. Then, the sample was placed directly opposite the sample hole and tested three times at different points.

[0110] (2) Texture determination: Cut the bacon sample to be measured into 2×2×1 cm size, and perform texture profile analysis (TPA) using the software provided by the food property tester to measure the hardness, elasticity, cohesion, chewiness and resilience of the bacon. The parameter setting conditions are: compression ratio 50%, pre-test rate 2.00 mm / s, test rate 1.00 mm / s, return rate 1.00 mm / s, trigger point load 5 g, probe P36 / R.

[0111] Table 4

[0112]

[0113] As can be seen from Table 4, compared with Comparative Examples 1-3, in Examples 1-2, the L* value and b* value of the cured duck legs treated in the Examples were significantly higher than those of the liquid smoked cured duck legs treated in the Comparative Examples (P<0.05), and the hardness and chewiness of the cured duck legs treated in the Examples were significantly higher than those of the liquid smoked cured duck legs treated in the Comparative Examples (P<0.05). Compared with Comparative Examples 4-6, the L* value and a* value of the cured duck legs treated in Example 1 were significantly higher than those of the liquid smoked cured duck legs treated in Comparative Examples 4-6 (P<0.05), and the hardness, elasticity and chewiness of the cured duck legs treated in Example 1 were significantly higher than those of the liquid smoked cured duck legs treated in Comparative Examples 4-6 (P<0.05), which shows that the composite smoke liquid has a more significant advantage in color and texture of the cured duck legs compared with the single smoke liquid, and the high and low temperature cycle baking and smoke liquid assisted pickling process play an important role in the formation of good texture of the cured duck legs.

[0114] In summary, the processing method of smoked liquid assisted pickling of cured duck legs of the present invention uses homemade composite smoked liquid to make the flavor quality of cured duck legs products uniform, have good smoked flavor, and can effectively and significantly reduce the content of polycyclic aromatic hydrocarbons, making the smoked cured duck legs safer to eat; while reducing the content of polycyclic aromatic hydrocarbons, the present invention can also ensure that the flavor of the cured duck legs products is not affected; the smoked liquid assisted pickling operation in the present invention is simple, simplifies the production process, avoids the problem of smoked liquid waste, is conducive to improving production efficiency, has low labor costs, and avoids the impact of traditional smoking on the environment; and the processing method provided by the present invention is suitable for industrialized and standardized production.

[0115] The above is only a preferred embodiment of the present invention and does not limit the present invention in any form. Therefore, any simple modification, equivalent change and modification made to the above embodiment according to the technical essence of the present invention without departing from the content of the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A method for processing bacon products assisted by smoked liquid, characterized in that: The following steps are involved: (1) pre-treating the raw meat; (2) Apply the marinade evenly on the surface of the meat and then marinate; The pickling liquid comprises edible salt, sodium D-isoascorbate, sodium nitrite and smoke liquid, and the amount of the smoke liquid added is 3-5% by weight of the meat; The smoke liquid is prepared by the following steps: dry distilling sawdust of dried apricot wood, persimmon wood and pomegranate wood in a mass ratio of (5-8): (2-5): (2-4) to generate smoke, condensing and collecting the smoke to obtain condensate, and post-treating the condensate to obtain the smoke liquid; (3) Place the marinated meat in a constant temperature and humidity chamber for baking.

2. The processing method according to claim 1, characterized in that: The bacon product is bacon duck legs.

3. The processing method according to claim 1 or 2, characterized in that: The apricot wood, persimmon wood and pomegranate wood are crushed to a particle size of 0.3-0.6 cm after drying.

4. The processing method according to claim 1 or 2, characterized in that: The heating rate of the dry distillation in step (2) is >10°C / min, the dry distillation temperature is 650-720°C, and the smoke is collected after 15 minutes of smoke generation.

5. The processing method according to claim 1 or 2, characterized in that: The post-treatment in step (2) includes purification using fruit shell columnar granular activated carbon.

6. The processing method according to claim 1 or 2, characterized in that: The pickling liquid in step (2) comprises the following components in percentage by weight of the meat: 2.5-4% edible salt, 0.1-0.2% sodium D-isoascorbate, 0.005-0.015% sodium nitrite, and 3-5% liquid smoke.

7. The processing method according to claim 1 or 2, characterized in that: The marinating in step (2) is tumbling and kneading for 3-5 hours.

8. The processing method according to claim 1 or 2, characterized in that: The baking in step (3) adopts high and low temperature cycle baking.

9. The processing method according to claim 8, characterized in that: The high and low temperature cycle baking: the high temperature baking stage parameters are: 0 to 4 hours, temperature 55° C., and relative humidity 70%; the low temperature baking stage parameters are: 4 to 8 hours, temperature 5° C., and no humidity limit.

10. The processing method according to claim 8, characterized in that: The high and low temperature cycle baking time is 4-6 days.

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