Application of fish oil as inhibitor for typical Maillard reaction associated hazardous substances in food processing

Abstract

The invention relates to the field of hot processing food safety, and particularly discloses an application of fish oil as an inhibitor for typical Maillard reaction associated hazardous substances in food processing. 0.001-40 [mu] L of fish oil is added into each g of food as a processing raw material. In the fish oil, the mass content of the total Omega-3 is 40%-90%; the typical Maillard reaction associated hazardous substances comprise acrylamide (AA) and carboxymethyl lysine (CML), and the CML comprises a free type and a combined type. According to the invention, while the content of associated harmful substances of typical Maillard reaction is reduced, the appearance characteristics of the fried potato product are improved, and the color of the fried potato product is brighter.

Description

Technical Field

[0001] The present invention relates to the field of thermally processed food safety, and in particular to the use of fish oil as an inhibitor of typical Maillard reaction-associated hazards in food processing (such as fried potato products). Background Art

[0002] In today's society, fast food culture has become an indispensable part of people's lives. During the high-temperature processing of fried potato foods such as French fries and potato chips, non-enzymatic browning such as Maillard reaction and caramelization reaction form food-specific coloring and flavoring substances, giving food color and flavor. However, Maillard reaction harmful products (MRHPs) such as acrylamide (AA) and advanced glycation end-products (AGEs) are produced during these reactions, which are potentially harmful to human health. Among them, carboxymethyl lysine (CML) was the first to be isolated and identified from food, and it is also the most important AGEs in food. Acrylamide has neurotoxicity and genotoxicity, and has been listed as a Class 2A carcinogen (probably carcinogenic to humans) by the International Agency for Research on Cancer (IARC). AGEs can combine with tissue cells in the body and destroy them, leading to oxidative stress and inflammation in the human body. The formation and accumulation of AGEs increase the potential risk of aging and health disorders. They are related to the development or deterioration of many chronic degenerative diseases (such as diabetes, atherosclerosis, Alzheimer's disease and Parkinson's disease, etc.). Therefore, inhibiting the typical Maillard reaction-associated hazards in fried potato products is of great significance to food safety issues.

[0003] Substances used as acrylamide inhibitors in fried foods often include some natural substance extracts, chemically synthesized substances, etc.

[0004] Regarding the inhibition research of acrylamide, the Chinese patent document with publication number CN202211156347.6 discloses an application of mangiferin, a composition for inhibiting the formation of acrylamide, and a preparation method, with an inhibition rate of acrylamide of 48.40% to 74.46%.

[0005] There are few studies on inhibitors of carboxymethyllysine. A Chinese patent document with publication number CN201811438306.X discloses an all-natural edible flavoring package and method for inhibiting the production of pyrogenically bound carboxymethyllysine in traditional braised meat products, thereby achieving the purpose of significantly reducing the production of pyrogenically bound carboxymethyllysine.

[0006] The invention of CN105076915B, "A fat-soluble bamboo leaf antioxidant prepared by an enzymatic method and its use", discloses fat-soluble bamboo leaf antioxidants, which have the following uses: (a) as an antioxidant for high-temperature food processing; (b) as an acrylamide inhibitor for high-temperature food processing; (c) for preparing an antioxidant for high-temperature food processing; (d) for preparing an acrylamide inhibitor for high-temperature food processing; (e) for inhibiting the formation of acrylamide and / or advanced glycation end products in high-temperature food processing. The advanced glycation end products are carboxymethyl lysine (CML) and / or carboxyethyl lysine (CEL).

[0007] Fish oil is an important source of n-3 polyunsaturated fatty acids (n-3 PUFA), rich in nutrients such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA, commonly known as brain gold), which is beneficial to human health and has important significance for preventing cardiovascular and cerebrovascular diseases. DHA and EPA are both polyunsaturated fatty acids in the omega-3 series and are the main components of omega-3.

[0008] The lipid nutrition dietary guidelines advocated by major health institutions around the world all encourage residents to increase their intake of unsaturated fatty acids (PUFA) and limit their intake of saturated fatty acids (SFA). Adding fish oil to the daily diet can supplement EPA and DHA for the human body, which is beneficial for preventing chronic degenerative diseases. Currently, the food industry is developing fish oil-fortified foods, and adding PUFA represented by deep-sea fish oil to edible oils, bread and other foods has become a development trend.

[0009] Currently, the published research on fish oil mainly focuses on adding fish oil to food through methods such as nano / microencapsulation technology to improve the quality and nutritional value of food. Summary of the invention

[0010] The technical problem to be solved by the present invention is to provide an application of fish oil as an inhibitor of typical Maillard reaction-associated hazards in food processing.

[0011] In order to solve the above technical problems, the present invention provides an application of fish oil as an inhibitor of typical Maillard reaction-associated hazards in food processing: 0.001-40 μL of fish oil is added to each gram of food used as a processing raw material.

[0012] As an improvement of the application of the present invention: the mass content of total Omega-3 in the fish oil is 40% to 90%;

[0013] The typical Maillard reaction associated hazards include acrylamide (AA) and carboxymethyl lysine (CML), and the CML includes free and bound forms.

[0014] That is, typical Maillard reaction-associated hazards include acrylamide, free carboxymethyllysine and bound carboxymethyllysine.

[0015] As a further improvement of the application of the present invention: in the fish oil, the mass contents of EPA and DHA are 10% to 80% and 5% to 50% respectively.

[0016] Description: DHA and EPA are the main components of omega-3.

[0017] As a further improvement of the application of the present invention: the food is potato.

[0018] As a further improvement of the application of the present invention: an air fryer is used to perform thermal processing on potatoes, the thermal processing temperature is 140-180° C., and the thermal processing time is 20-30 minutes.

[0019] As a further improvement of the application of the present invention: 20-40 μL of fish oil is added to each gram of potato, preferably 30 μL of fish oil is added to each gram of potato.

[0020] The current existing technology lacks information on the effects of fish oil on typical MRHPs in food and their formation patterns. Therefore, exploring the effects of fish oil on the MRHPs content in fried potatoes will be of great significance to the food processing industry.

[0021] The invention provides fish oil as a typical Maillard reaction associated hazard inhibitor, which is applied to the processing process of fried potato products; while reducing the content of typical Maillard reaction associated hazards, the appearance characteristics of the fried potato products are improved, so that the color of the fried potato products is brighter, the red degree is reduced, and the yellow degree is increased.

[0022] When the fish oil of the present invention is used as a typical Maillard reaction associated hazard inhibitor in fried potato products, its inhibition rate on typical Maillard reaction associated hazards is determined by comparing the content of acrylamide and carboxymethyl lysine generated during the heat processing of food raw materials with and without fish oil added, wherein the determination method of acrylamide and carboxymethyl lysine adopts ultra-high phase liquid chromatography-tandem mass spectrometry. It is shown by measurement that after using different amounts of fish oil, the inhibition rate of acrylamide is 2% to 50%, the inhibition rate of free carboxymethyl lysine is 10% to 50%, and the inhibition rate of bound carboxymethyl lysine is 0% to 20%. It is calculated by weighted average method that after using different amounts of fish oil, the total inhibition rate of MRHPs in fried potatoes is 15% to 80%, and the calculation formula is as follows:

[0023] R=1-(1-r1)(1-r2)(1-r3)

[0024] Among them, R is the total inhibition rate of MRHPs, r1 is the inhibition rate of acrylamide, r2 is the inhibition rate of free carboxymethyllysine, and r3 is the inhibition rate of bound carboxymethyllysine. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 (a) AA, (b) free CML and (c) bound CML contents in fried potatoes at different fish oil dosages.

[0026] Figure 2 Intensity of the color parameters (a) a*, (b) b* and (c) L* values ​​of potato chips at different fish oil addition dosages and heating times. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the embodiments and drawings. It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention.

[0028] In the present invention:

[0029] The fish oil used in the present invention refers to the fish oil prepared by Royal DSM, and its mass contents of EPA, DHA and total Omega-3 are 10% to 80%, 5% to 50%, and 40% to 90% respectively; its acid value is less than 1 mg KOH / g, and its peroxide value is less than 3 mg equivalent / kg.

[0030] The actual usage is as follows:

[0031] The fish oil was uniformly mixed with the potato raw material (i.e., the fish oil was evenly spread on the potato raw material) and then heat-processed to serve as the test group; the potato without fish oil was heat-processed to serve as the blank control;

[0032] The potato raw materials of the test group / blank control were heat-processed to cause the Maillard reaction, which was used as a reaction system for producing typical Maillard reaction-associated hazards.

[0033] That is, after adding fish oil within the scope of the invention to the test group, the production of typical Maillard reaction-associated harmful substances was measured under the same conditions, and compared with the blank control group, the inhibition rate of adding fish oil on typical Maillard reaction-associated harmful substances was calculated. Typical Maillard reaction-associated harmful substances include acrylamide and carboxymethyl lysine, wherein carboxymethyl lysine includes free and bound states, and its determination is carried out by UPLC-MS / MS method, and the specific conditions are as follows:

[0034] Instrument: Waters ACQUITY ultra-high performance liquid chromatograph

[0035] Ultra-high performance liquid chromatography conditions: 0.1% formic acid aqueous solution (i.e., formic acid volume concentration of 0.1%) as mobile phase A, 0.1% formic acid acetonitrile solution (i.e., formic acid volume concentration of 0.1%) as mobile phase B, elution program: 0-1.0 min, 2% mobile phase B; 1.0-3.5 min, 2%-10% mobile phase B; 3.5-4.0 min, 10%-100% mobile phase B; 4.0-6.0 min, 100% mobile phase B; 6.0-6.1 min, 100%-2% mobile phase B; 6.1-8.1 min, 2% mobile phase B;

[0036] UPLC conditions:

[0037] Chromatographic column: Waters ACQUITY UPLC HSS T3 column, 2.1mm×150mm, 1.8μm; the column pressure that this column can bear is many times higher than that of ordinary liquid phase columns, which greatly improves the detection efficiency;

[0038] Column temperature: 35°C;

[0039] Flow rate 0.2 mL min-1;

[0040] Injection volume: 2 μL.

[0041] Instrument: AB SCIEX QTRAP 6500+ triple quadrupole / compound ion trap mass spectrometer

[0042] Mass spectrometry conditions: electrospray ionization was used and negative ion scanning was performed in multiple reaction monitoring mode.

[0043] Mass spectrometry conditions:

[0044] Spray voltage 4500V;

[0045] Ion source heating temperature 500°C;

[0046] The air curtain gas is 50Psi;

[0047] Atomizing gas is 50Psi;

[0048] The auxiliary heating gas is 50 psi.

[0049] The sample pretreatment steps for determination of acrylamide and carboxymethyl lysine content are as follows:

[0050] (1) Sample weighing: Weigh 200 mg of the ground sample into a glass digestion tube for subsequent processing;

[0051] (2) Degreasing and extraction: Add 3 mL of water, 3 mL of n-hexane and 50 ng of AA-d3 internal standard, vortex thoroughly for 1 min, centrifuge at 6500 r / min for 5 min at 0°C, discard the n-hexane layer, keep the middle aqueous phase, and repeat the above n-hexane degreasing step twice. Combine the aqueous phases for the determination and analysis of AA and free CML (Part A), and the bottom precipitate for the determination and analysis of bound CML (Part B).

[0052] (3) Extraction and purification of part A: Add 2.5 g sodium chloride, 6 mL acetonitrile and 50 ng CML-d4 internal standard to the above-collected aqueous phase, vortex thoroughly for 1 min, and centrifuge for 5 min (6500 r / min), retaining the upper acetonitrile phase. Blow dry the acetonitrile phase with nitrogen, reconstitute with 3 mL ethyl acetate, vortex thoroughly for 5 min, and centrifuge (6500 r / min), discard the bottom impurities (if any), and retain the ethyl acetate phase.

[0053] (4) Solid phase extraction cleanup of part A: A PolyPlus MCX SPE column (3 mL, 60 mg) was used, which was activated with 3 mL of methanol and equilibrated with 3 mL of water in advance. The sample solution was then passed through the column and eluted with 2 mL of formic acid-ethyl acetate solution (9:91, v / v). The column solution and the first elution solution were collected in the same centrifuge tube (for the determination of AA). The second elution was performed with 3 mL of methanol. Finally, 4 mL of ammonia-methanol solution (5:95, v / v) was used for elution, and the eluate was collected in a new centrifuge tube (for the determination of free CML). The collected sample solutions were blown dry with nitrogen, re-dissolved with 1 mL of 0.1% formic acid water, and then passed through a membrane (0.22 μm) for UPLC-MS / MS detection and analysis.

[0054] (5) Reduction of Part B: Add 1.5 mL of 0.2 mol / L sodium tetraborate buffer, 100 μL of n-octanol, and 1 mL of sodium borohydride solution to the precipitate from step (2), vortex thoroughly for 30 seconds, and place at room temperature for 4 hours. This step is to prevent the formation of new CML during acid hydrolysis.

[0055] (6) Hydrolysis of Part B: Add 2 mL of 6 mol / L hydrochloric acid solution to the reducing solution, fill with nitrogen for 3 min, and hydrolyze at 110°C for 18 h. Filter the precipitate with a 0.45 μm filter membrane, and dilute the supernatant to 10 mL with ultrapure water. Take out 500 μL and blow dry with nitrogen. Add 3 mL of water to reconstitute, then add 50 ng of CML-d4 internal standard, and vortex thoroughly for 1 min.

[0056] (7) Solid phase extraction cleanup of part B: A PolyPlus MCX SPE column (3 mL, 60 mg) was used, which was pre-activated with 3 mL of methanol and equilibrated with 3 mL of water. After the sample solution passed through the column, it was rinsed with 3 mL of methanol. Then it was eluted with 4 mL of ammonia-methanol solution (5:95, v / v), and the eluate was collected in a centrifuge tube (for the determination of bound CML). After drying with nitrogen, it was re-dissolved with 1 mL of 0.1% formic acid water, vortexed thoroughly for 1 min, and passed through a membrane (0.22 μm) for UPLC-MS / MS detection and analysis.

[0057] Example 1: Study on the inhibitory effect of adding fish oil on typical Maillard reaction-associated hazards in potato products.

[0058] The mass contents of EPA, DHA and total Omega-3 in fish oil are 46%, 18% and 72% respectively; its acid value is less than 1 mg KOH / g, and its peroxide value is less than 3 mg equivalent / kg.

[0059] Homemade potato chips were used as fried potato samples and the thermal processing flow of potato chips as blank controls was as follows:

[0060] Fresh potatoes → wash and peel → cut into uniform thin slices with a thickness of 2 mm → cut into potato slices with a diameter of 5 cm using a circular blade → soak in ultrapure water for 10 min → drain → put the drained potato slices into an air fryer for thermal processing (the set temperature is 160°C, and the processing time is shown in Table 1) → remove from the pan → grind into powder using a food grinder → place in a 50 mL centrifuge tube and seal for storage.

[0061] The difference between the experimental group and the blank control is that after the draining process, an appropriate amount of fish oil is first added to the drained potato slices for uniform mixing (the amount of fish oil added is described in Table 1 below), and then the drained potato slices mixed with fish oil are placed in the air fryer for thermal processing; the rest is the same as the blank control.

[0062] Acrylamide and standards, carboxymethyllysine standards, acrylamide-d3 internal standard, and carboxymethyllysine-d4 internal standard were purchased from Shanghai MacLean Biochemical Technology Co., Ltd.

[0063] At a temperature of 160°C, different amounts of fish oil additives were added to the surface of potato chips. Fried potato chips were made at different time points during the continuous heating process. After grinding and sampling, the UPLC-MS / MS method was used to simultaneously detect the contents of AA, free CML and bound CML in fried potatoes under different thermal processing conditions. The group without fish oil addition was used as the control group, and 3 parallels were set up for each group. The test results are shown in Table 1.

[0064] Table 1. AA and CML contents of fried potatoes at different fish oil addition amounts and heating times at 160°C (n=3)

[0065]

[0066] As can be seen from Table 1, fish oil has a certain inhibitory effect on acrylamide, free carboxymethyl lysine and bound carboxymethyl lysine.

[0067] Experiment 1: The potato chips obtained in Example 1 were subjected to CIELAB color attribute determination:

[0068] That is, fish oil was added to potato chips at a heat processing temperature of 160°C at a dosage of 0, 20, 30, and 40 μL / g, and potato chips were prepared under heating conditions of 20, 25, and 30 min, respectively, and ground into powder, and samples were taken for CIELAB color attribute determination. The group without fish oil addition was used as the control group, and 3 parallels were set for each group. The test results are shown in Table 2 and Figure 2 shown.

[0069] The results show (Table 2) that when heated at 160°C for 20-30 min, the red index a* of the fried potato chips with added fish oil is lower than that of the control group, while the yellow index b* and brightness index L* are higher than those of the control group. This indicates that when other conditions are the same, the color of the fried potato chips with added fish oil will be brighter, with a lighter red and a darker yellow ( Figure 2 ).

[0070] Table 2 Color parameters of fried potatoes at different fish oil addition amounts and heating times (n=3)

[0071]

[0072] The Friedman M rank sum test was used to investigate the effect of fish oil on the color of potato chips. The results showed that fish oil had statistically significant effects on a* (p<0.0001), b* (p<0.0001) and L* (p<0.01) (as shown in Table 3).

[0073] Table 3 Results of Friedman M rank sum test on the effect of fish oil on color parameters of fried potatoes

[0074]

[0075] Note: ** p<0.01; *** p<0.0001

[0076] In summary, the effect of fish oil on the color level of fried potatoes is related to the dosage of fish oil. Adding an appropriate amount of fish oil will inhibit the process of Maillard reaction and reduce the formation of browning products, thereby increasing the brightness and yellowness of the color of the fried potato chips and reducing the redness, which is in sharp contrast to the control group. In addition, there are obvious differences in the color of fried potato chips at different fish oil dosages.

[0077] Example 2: The temperature of the heat treatment in the air fryer in Example 1 was changed from 160°C to 140°C, and the rest was the same as Example 1. The results are shown in Table 4 below:

[0078] Table 4

[0079]

[0080] Note: The above are cases where the AA and CML contents are low at each fish oil addition dosage, that is, if the heating time is prolonged, the AA and CML contents will increase accordingly.

[0081] Example 3: The temperature of the heat treatment in the air fryer in Example 1 was changed from 160°C to 180°C, and the rest was the same as Example 1. The results are shown in Table 5 below:

[0082] Table 5

[0083]

[0084] Note: The above are cases where the AA and CML contents are low at each fish oil addition dosage, that is, if the heating time is prolonged, the AA and CML contents will increase accordingly.

[0085] Example 4: The mass contents of EPA, DHA and total Omega-3 in the fish oil in Example 1 were changed to 30%, 10% and 46% respectively; the rest was the same as in Example 1. The results were as shown in Table 6:

[0086] Table 6

[0087]

[0088]

[0089] Note: The above are cases where the AA and CML contents are low at each fish oil addition dosage, that is, if the heating time is prolonged, the AA and CML contents will increase accordingly.

[0090] Example 5: The mass contents of EPA, DHA and total Omega-3 in the fish oil in Example 1 were changed to 56%, 26% and 86% respectively; the rest was the same as in Example 1. The results are shown in Table 7 below:

[0091] Table 7

[0092]

[0093] Note: The above are cases where the AA and CML contents are low at each fish oil additive dosage, that is, if the heating time is prolonged, the AA and CML contents will increase accordingly.

[0094] Finally, it should be noted that the above examples are only some specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and there are many variations. All variations that can be directly derived or associated with the content disclosed by a person skilled in the art should be considered as the protection scope of the present invention.

Claims

1. The use of fish oil as an inhibitor of typical Maillard reaction-associated hazards in food processing, characterized in that: Add 0.001 to 40 μL of fish oil to every gram of food used as processing raw material.

2. The use according to claim 1, characterized in that: The fish oil has a total Omega-3 content of 40% to 90% by mass; Typical Maillard reaction-associated hazards include acrylamide (AA) and carboxymethyllysine (CML), and the CML includes free and bound forms.

3. The use according to claim 2, characterized in that: In the fish oil, the mass contents of EPA and DHA are 10% to 80% and 5% to 50% respectively.

4. The use according to any one of claims 1 to 3, characterized in that: The food is potato.

5. The use according to claim 4, characterized in that: The air fryer is used to heat-process the potatoes at a temperature of 140 to 180° C. and a time of 20 to 30 minutes.

6. The use according to claim 5, characterized in that: Add 20-40 μL of fish oil per gram of potato.

7. The use according to claim 6, characterized in that: Add 30 μL of fish oil per gram of potato.

8. The use according to any one of claims 4 to 7, characterized in that: The comprehensive inhibition rate of the fish oil on harmful substances associated with the Maillard reaction is 15% to 80%.

9. The use according to any one of claims 4 to 8, characterized in that: The fish oil can improve the yellow saturation of potato products, making the color brighter.

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