Sesame paste not prone to floating oil and caking and preparation method of sesame paste

Abstract

The invention mainly relates to the technical field of food seasoning sauce processing, in particular to sesame paste not prone to floating oil and caking and a preparation method of the sesame paste. Specifically, the invention provides the preparation method of the sesame extract, and the method comprises the following steps: carrying out alcohol extraction on a sesame raw material subjected to oil removal treatment to obtain an alcohol-soluble component, extracting the alcohol-soluble component, and purifying the extracted component to obtain the sesame extract, wherein in the purification step, resin is used for purification, alcohol or an aqueous solution of the alcohol is used for elution, and the volume concentration of the aqueous solution of the alcohol is larger than or equal to 80%. The invention also provides a preparation method and application of the sesame extract. The sesame extract can improve the viscosity and / or stability of the sesame paste.

Description

Technical Field

[0001] The present invention mainly relates to the technical field of food flavor sauce processing, and particularly relates to a sesame paste that is not prone to floating oil and caking and a preparation method thereof. Background Art

[0002] Sesame, also known as flaxseed and oilseed, belongs to the Pedaliaceae family and Sesamum genus, and is an annual herb. China ranks fourth in the world in terms of sesame planting area, but both the unit yield and total output rank first in the world. Sesame contains rich nutritional value. Among them, the average oil content is 54.74%. The fatty acids are mainly composed of two unsaturated fatty acids, oleic acid and linoleic acid, with contents of 38.39% and 46.26% respectively. Among them, linoleic acid can play a role in inhibiting the formation of arterial thrombosis and reducing serum cholesterol. The protein content in sesame is about 22.12%, and the content of essential amino acids for the human body is high, such as methionine. In addition, sesame also contains antioxidant substances such as vitamin E, sesamin, sesamolin, and sesamol.

[0003] At present, the main sesame processing products in China are sesame oil, sesame paste, peeled sesame, roasted sesame, etc. Among them, sesame paste is a flavor food with high nutritional value and is often used in cold dishes, hot dry noodles, hot pot dipping sauces, etc. to enhance the flavor. Consuming sesame paste can not only meet people's taste bud needs, but also after sesame is ground, the nutrients and active ingredients in sesame are more easily absorbed by the human body, giving play to its nutritional and health care value. In regions such as North China, Northeast China, and Central China in China, sesame paste is deeply loved by consumers.

[0004] At present, during the circulation process of sesame paste products in the market, there is a problem of poor stability, that is, floating oil will precipitate after sesame paste is placed for one month. The longer the time, the more floating oil. The precipitation of floating oil in sesame paste leads to the hardening and solidification of the lower layer of sesame paste body, which has an adverse impact on the original flavor, spreadability, and sensory quality of the product, shortens the storage period and shelf life, affects the popularity and commercial value of sesame paste processing products in the market, and restricts the expansion of the scale of sesame paste products. How to make sesame paste maintain high stability and slow down or prevent the precipitation of floating oil in sesame paste is the key to solving the large-scale production of sesame paste. Some domestic scholars have studied to improve the product stability by adding natural antioxidants and emulsifiers. Although the stability of sesame paste has been improved to a certain extent, there are two problems. One is that for the added foreign additives, the product name cannot be labeled as "pure sesame paste"; the other is that it affects the flavor of the product. Summary of the Invention

[0005] The purpose of the present invention is to add the substances contained in sesame paste itself to sesame paste to improve the stability of sesame paste without affecting its purity and flavor.

[0006] The first aspect of the present invention provides a method for preparing a sesame extract, the method comprising the steps of subjecting defatted sesame raw materials to alcohol extraction to obtain an alcohol-soluble component, extracting the alcohol-soluble component, and purifying the extracted component to obtain the sesame extract; wherein, in the purification step, purification is carried out using a resin and elution is carried out using an alcohol or an aqueous solution thereof, wherein the volume concentration of the aqueous solution of the alcohol is greater than or equal to 80%.

[0007] In one or more embodiments, the sesame raw materials are selected from one or more of sesame seeds, sesame paste, sesame meal, and sesame cake.

[0008] In one or more embodiments, the defatting includes extracting with an organic solvent such as n-hexane to obtain an organic solvent layer, and removing the organic solvent in the organic solvent layer to obtain a solid component.

[0009] In one or more embodiments, the alcohol extraction uses an alcohol solution to extract the solid component obtained in the defatting step to obtain an alcohol-soluble component.

[0010] In one or more embodiments, the alcohol is ethanol.

[0011] In one or more embodiments, the volume concentration of the alcohol in the aqueous solution of the alcohol is 20% - 80%.

[0012] In one or more embodiments, the volume concentration of the alcohol in the aqueous solution of the alcohol is 70 ± 10%.

[0013] In one or more embodiments, the extraction includes using n-butanol to extract the alcohol-soluble component dissolved in water to obtain an n-butanol layer component.

[0014] In one or more embodiments, the volume ratio of the alcohol-soluble component to water is 1:(1 - 3), such as 1:1.

[0015] In one or more embodiments, the n-butanol is a water-saturated n-butanol solution, more preferably a 1:1 water-saturated n-butanol solution.

[0016] In one or more embodiments, the purification uses a styrene-type non-polar copolymer resin.

[0017] In one or more embodiments, the solvent used for elution is an ethanol solution with a volume concentration of 85% - 100%, 90% - 95%, or 80% - 95%.

[0018] In one or more embodiments, the volume of the alcohol solution used for elution is 1 - 10 times, preferably 3 - 7 times, or 5 - 7 times the volume of the resin.

[0019] In one or more embodiments, the elution rate is 1 - 5 BV / h, preferably 1 - 3 BV / h.

[0020] In one or more embodiments, the method comprises:

[0021] Degreasing: Extracting the sesame paste with n-hexane several times, combining the filtrates obtained each time, removing the n-hexane, and obtaining a solid component;

[0022] Alcohol extraction: Extracting the solid component with an ethanol solution having a volume concentration of 70 ± 10% several times, combining the filtrates obtained each time, removing the solvent, and obtaining an alcohol-soluble component;

[0023] Extraction: Dissolving the alcohol-soluble component in water, extracting with a 1:1 water-saturated n-butanol solution several times, combining the n-butanol extraction portions obtained each time, removing the n-butanol, and drying to obtain an n-butanol layer component; and

[0024] Purification: Dissolving the n-butanol layer component in water, transferring it to a chromatography column filled with a styrene-type non-polar copolymer resin, eluting with an ethanol solution having a volume concentration of 85-100% at an elution rate of 1-5 BV / h, the volume of the alcohol solution used for elution being 3-7 times the volume of the resin, collecting the eluate, removing the solvent, and drying to obtain the sesame extract.

[0025] The second aspect of the present invention provides a sesame extract prepared by the method according to any one of the embodiments herein; preferably, the protein content of the sesame extract is ≤10%.

[0026] The third aspect of the present invention provides a method for increasing the viscosity and / or stability of sesame paste, the method comprising adding the sesame extract according to any one of the embodiments herein or an aqueous solution thereof to the sauce used for preparing sesame paste during the preparation of sesame paste, and the step of preparing sesame paste from the sauce added with the sesame paste extract; wherein, the amount of the sesame extract added is more than 1% by weight of the sauce, preferably 1-3%, more preferably 1.5-2%.

[0027] In one or more embodiments, the method further comprises the step of preparing the sesame extract according to any one of the embodiments herein.

[0028] The fourth aspect of the present invention provides a sesame paste, which contains more than 1% by weight of the sesame extract according to claim 4, preferably 1-3%, more preferably 1.5-2% of the sesame extract based on the weight of the sesame paste.

[0029] In one or more embodiments, the viscosity of the sesame paste is ≥10000 CP.S, preferably ≥11000 CP.S, more preferably ≥13000 CP.S.

[0030] The fifth aspect of the present invention provides the application of the method and / or sesame extract as described in any one of the embodiments herein in enhancing the viscosity and / or stability of a sauce; preferably, the sauce is sesame paste.

[0031] The sixth aspect of the present invention provides a food containing the sesame extract or sesame paste as described in any one of the embodiments herein. Description of the Drawings

[0032] Figure 1 It is the infrared analysis spectrum of the water extract.

[0033] Figure 2 It is the infrared analysis spectrum of the 30% ethanol extract.

[0034] Figure 3 It is the infrared analysis spectrum of the 50% ethanol extract.

[0035] Figure 4 It is the infrared analysis spectrum of the 75% ethanol extract.

[0036] Figure 5 It is the infrared analysis spectrum of the 95% ethanol extract. Detailed Embodiments

[0037] As used herein, terms such as "comprising", "including", "containing" and similar terms encompass the meanings of "consisting essentially of" and "consisting of". For example, when it is disclosed herein that "A comprises B and C", "A consists essentially of B and C" and "A consists of B and C" should be considered to have been disclosed herein.

[0038] As used herein, unless otherwise specified, percentages refer to mass (or weight) percentages and ratios refer to mass (or weight) ratios.

[0039] As used herein, the "paste" refers to the part remaining after removing water from a conventional sauce. When calculating the content by the mass or weight of the "paste", the mass or weight of the "paste" does not include the mass or weight of the concentrated sesame oil extract and water described herein; when calculating the content by the mass or weight of the "sauce", the mass or weight of the "sauce" refers to the mass or weight of the entire sauce, that is, the mass or weight of water and the concentrated sesame oil extract is also included.

[0040] As used herein, when describing embodiments or examples, it should be understood that they are not used to limit the present invention to these embodiments or examples. On the contrary, all alternatives, modifications and equivalents of the methods and materials described in the present invention can be covered within the scope defined by the claims.

[0041] In this text, for the sake of concise description, not all possible combinations of all technical features in each implementation or embodiment are described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each implementation or embodiment can be combined arbitrarily, and all possible combinations should be considered as the scope described in this specification.

[0042] Through in-depth research, the inventors found that adding sesame extract to sesame paste can improve the viscosity and stability of sesame paste, thereby completing the present invention. In this text, the viscosity is tested by the method described in the present invention; the stability is characterized by the centrifugal floating oil rate, and the lower the centrifugal floating oil rate, the more stable the sesame paste.

[0043] The sesame extract described in this text can be an extract of sesame raw materials with alcohol or an aqueous solution of alcohol.

[0044] The sesame extract described in this text is prepared by including the following steps: degreasing, extraction, extraction and purification.

[0045] The degreasing step of this application can be implemented by using degreasing methods well-known in the art. For example, sesame raw materials can be leached with an organic solvent such as n-hexane to remove the oil part and the solid insoluble part that is insoluble in the used organic solvent, and obtain the components dissolved in the organic solvent such as n-hexane present in sesame.

[0046] In this text, the sesame raw materials can be one or more of sesame seeds, sesame paste, sesame meal and sesame cake. When using sesame seeds, to improve the extraction efficiency, it is preferred to crush the sesame seeds or make them into sesame paste and then leach with an organic solvent such as n-hexane. In some embodiments, this application uses pure sesame paste as the sesame raw material for organic solvent extraction. There are no special restrictions on the extraction time and number of times, which can be determined according to the amount of the used organic solvent, the amount of the sesame raw material, and the state of the sesame raw material (such as whether it is sesame seeds or sesame paste). For example, the sesame raw materials can be leached with an organic solvent more than once, such as leaching 2 to 4 times. The extraction time for each time can be greater than 1 h. In some embodiments, the extraction time for each time is 2 to 8 h, such as 2 to 5 h. When leaching, the mass of the used organic solvent can be 1 to 5 times that of the sesame raw material, such as 2 to 4 times. When implementing multiple extractions, the filtrate parts obtained each time can be combined. The filtrate can be concentrated by, for example, vacuum rotary evaporation to further remove the residual organic solvent in the filtrate and obtain the solid components dissolved in the organic solvent. The residual organic solvent can be removed by heating and drying. The drying can be, for example, hot air drying. The drying temperature can be 50 to 80 °C, preferably 60 to 70 °C.

[0047] In some embodiments, the defatting step includes extraction with an organic solvent (such as n-hexane) to obtain an organic solvent layer, and the steps of removing the organic solvent in the organic solvent layer and obtaining a solid component. The extraction method can be as described above, and the method for removing the organic solvent can include steps such as vacuum rotary evaporation and drying described above.

[0048] The extraction step herein can use an alcohol solution to extract the solid component obtained in the defatting step to obtain an alcohol-soluble component. The alcohol used for extraction is preferably ethanol. An aqueous solution of alcohol can be used for extraction. Generally, the volume concentration of alcohol in the aqueous solution of alcohol is 20% to 80%, such as 70±10%. In some embodiments, an aqueous ethanol solution with a volume concentration of 70% to 80% is used for alcohol extraction (extraction). During alcohol extraction, the mass of the extraction solvent (such as the aqueous solution of the alcohol) used can be 1 to 5 times, such as 2 to 4 times, that of the solid component. It should be understood that the length and number of extraction times are related to the amount of the product obtained by extraction. Therefore, those skilled in the art can select the number of extractions of 1 time or more than 2 times and the extraction time for each extraction according to the actual situation. For example, the extraction time for each extraction can be more than 0.5 h, such as 1 to 8 h or 2 to 5 h. After the extraction is completed, the alcohol and water in the filtrate can be removed to obtain an alcohol-soluble component. The alcohol and water can be removed by, for example, vacuum rotary evaporation.

[0049] In the extraction step herein, the alcohol-soluble component obtained in the extraction step can be first dissolved in water, and then extracted with n-butanol. The volume ratio of the alcohol-soluble component to water can be 1:(1 to 3), such as 1:1. The n-butanol is preferably a water-saturated n-butanol solution, more preferably a 1:1 water-saturated n-butanol solution. When dissolving with n-butanol, ultrasound can be applied. It should be understood that the purpose of ultrasound is to promote dissolution. Therefore, those skilled in the art can select the conditions of ultrasound according to the actual situation. The exemplary ultrasound time can be 10 - 60 min. It should be understood that the number and length of extraction times are related to the amount of the product obtained by extraction. Therefore, those skilled in the art can select the appropriate number and time of extraction according to the actual situation. For example, the number of extractions can be 1 to 5 times, and the extraction time for each extraction can be 10 min to 1 h. The n-butanol extraction part can be concentrated to obtain an n-butanol layer component. Concentration can be carried out by, for example, rotary evaporation, and rotary evaporation can be carried out under vacuum conditions. After rotary evaporation, the component can be further dried, such as by freeze-drying.

[0050] In the purification step of the present text, the n-butanol layer component can be first dissolved in water, and the sesame extract described in the present text can be obtained by separation and purification using resin. The mass of the water used can be 5 to 15 times, such as 10 to 15 times, the mass of the n-butanol layer component to be dissolved. During the dissolution process, ultrasound can be applied. It should be understood that the purpose of ultrasound is to promote dissolution. Therefore, those skilled in the art can select the conditions of ultrasound according to the actual situation. The exemplary ultrasound time can be 10 - 60 min. The resin used in the present text can be a non-polar resin commonly used in the art with a wide applicable range, and such resins have a strong adsorption capacity for non-polar or weakly polar organic compounds. Exemplary non-polar resins include the commonly used D-type non-polar resins in the art, preferably styrene-type non-polar copolymer resins (such as D101 macroporous resin). During the elution process, alcohol is used for elution. It is preferred to use ethanol for elution. More preferably, the volume concentration of the alcohol solution (usually an aqueous solution of ethanol) used is greater than or equal to 80%, such as 85% - 100%, 90% - 95% or 80% - 95%. It should be understood that when the volume concentration is 100%, pure alcohol solution is used for elution. The volume of the alcohol solution used for elution can be 1 to 10 times, preferably 3 to 7 times or 5 to 7 times the volume of the resin. The elution rate can be 1 - 5 BV / h, preferably 1 - 3 BV / h. During the elution process, the eluate is collected, concentrated and dried, and thus the sesame extract of the present application can be obtained. The concentration can be vacuum rotary evaporation concentration, and the drying can be freeze drying. The conventional vacuum rotary evaporation concentration and freeze drying processes can be used to implement the present invention.

[0051] Preferably, the protein content of the sesame extract of the present application is ≤10%.

[0052] Therefore, in some embodiments, the present invention provides a sesame extract, the components of which are substantially the same as those of the sesame extract prepared by using the preparation method of the sesame extract described in any one of the embodiments of the present text. The "substantially the same" described in the present text means that among the components contained in the sesame extract, the components accounting for more than 10%, preferably more than 20%, more preferably more than 30% of the total weight of the sesame extract are completely the same.

[0053] The aqueous solution of the sesame extract can be prepared as needed. Usually, the sesame extract can be added to pure water and treated under ultrasonic conditions of 30 - 40°C and 50 - 200 Hz until completely dissolved, thereby preparing the aqueous solution of the sesame extract. There is no special limitation on the content of the sesame extract in the aqueous solution.

[0054] The sesame extract of the present invention can improve the viscosity and / or stability of sesame paste. Sesame paste is a polydisperse system and belongs to a solid-liquid heterogeneous system. The liquid phase is mainly sesame oil, and the solid phase consists of denatured proteins, carbohydrates, lignocellulose, ash, and the combination of proteins and other substances. The macromolecular compounds in the solid phase contain both hydrophilic groups and lipophilic groups. Therefore, they can be wetted by both water and oil. However, due to the much stronger hydrophilicity than lipophilicity, the binding force of the macromolecular compounds in the solid phase to water is much greater than that to oil. Due to the presence of water in sesame paste, small solid particles bond into large particles after absorbing water. The movement law of large particles in the oil phase conforms to Stokes' law, that is:

[0055]

[0056] wherein, Vg - sedimentation velocity, d - particle diameter, ρ P - particle density, ρ f - oil phase density, η - oil phase viscosity, g - acceleration due to gravity.

[0057] According to Stokes' law, the sedimentation velocity of particles is proportional to the particle diameter, proportional to the density difference between the two phases, and inversely proportional to the viscosity. The solid molecules move towards the solid phase, small particles spontaneously form large particles, the density of the solid particles is greater than that of the oil droplets, the oil droplets float upwards, and finally reach the top of the sauce body to form a pure oil phase, while the solids sink to the bottom, ultimately resulting in oil-sauce separation. Therefore, the increase in viscosity is related to improving the stability of sesame paste.

[0058] It should be noted that soluble sugars and crude proteins are known in the art to have a positive effect on the storage stability of sesame paste. However, the precursor substances eluted with the aqueous solution of alcohol in this article are bitter, there are few or no sugar substances present, and there is also less protein in the eluate (as shown in Table 1). Therefore, the improvement in the stability of the sesame paste in this article is not brought about by sugar substances or crude proteins.

[0059] Therefore, in some embodiments, the present invention provides the application of the sesame extract described in any embodiment of this article in enhancing the viscosity and / or stability of the sauce, or the application in preparing a sauce with improved viscosity and / or stability; the sauce is preferably sesame paste.

[0060] In some embodiments, the present invention provides a sauce having enhanced viscosity and / or stability. In the sauce with enhanced viscosity and / or stability according to the present invention, the content of the sesame extract is ≥1% by the mass of the sauce. In some embodiments, the content of the sesame extract is 1%-3%. In some embodiments, the content of the sesame extract is 1.5%-2%. In some embodiments, the viscosity of the sauce is ≥10,000 CP.S, preferably ≥11,000 CP.S, more preferably ≥13,000 CP.S. Preferably, the centrifugal floating oil rate of the sauce is ≤18.3% or ≤18.0% or ≤17.5%; preferably, compared with a sauce having the same other ingredients without the sesame extract, the centrifugal floating oil rate of the sauce is reduced by at least 1.3% or at least 5% or at least 7%. In some embodiments, the sauce is sesame paste.

[0061] In some embodiments, the present invention provides a method for preparing a sauce or a method for enhancing the viscosity and / or stability of a sauce. During the preparation of the sauce, the sesame extract or its aqueous solution described in any embodiment herein can be directly added to the semi-finished sauce or the finished sauce, and the sauce having enhanced viscosity and / or stability is prepared from the semi-finished sauce added with the sesame extract or its aqueous solution. Alternatively, the sesame extract or its aqueous solution can be added to the prepared product sauce and stirred evenly to prepare a sauce with enhanced viscosity and / or stability. The finished sauce or semi-finished sauce can be prepared by methods well known in the art. For example, when the sauce is sesame paste, the preparation method of sesame paste includes the steps of screening sesame, washing with water, drying, and grinding. For other sauces, their preparation methods may not be similar to that of sesame paste, but the sesame extract or its aqueous solution described in any embodiment herein can also be added (usually added to the prepared semi-finished sauce) in appropriate preparation steps.

[0062] Therefore, in some embodiments, the method for preparing a sauce or the method for enhancing the viscosity and / or stability of a sauce described herein further includes the step of preparing a semi-finished or finished sauce.

[0063] In some embodiments, the method for preparing a sauce or the method for enhancing the viscosity and / or stability of a sauce described herein may further include the step of preparing the sesame extract or its aqueous solution by the method described in any of the foregoing embodiments.

[0064] In some embodiments, the present invention further provides a mixed sauce, which contains the above-mentioned sauce having enhanced viscosity and / or stability.

[0065] The present invention further provides a food, which contains the above-mentioned sauce or is prepared from the above-mentioned sauce.

[0066] The present invention has the following beneficial effects:

[0067] The present invention utilizes substances inherent in sesame paste and adds them to the sesame paste to increase its viscosity and stability.

[0068] The present invention will be further described below by way of specific embodiments. It should be understood that these embodiments are merely illustrative and not intended to limit the scope of the present invention. The methods and reagents used in the embodiments are conventional methods and reagents in the art unless otherwise specified.

[0069] Viscosity measurement method

[0070] Equipment: Rotary viscometer

[0071] Operating steps:

[0072] (1) Take a 100 ml beaker, fill the beaker with the paste up to 80 ml, heat it to 70 °C, and immediately conduct the test;

[0073] (2) Remove the protective cap at the rotor connection, and level the instrument;

[0074] (3) Connect the power supply;

[0075] (4) Automatically calibrate the equipment (do not connect the rotor);

[0076] (5) Set the parameters: rotor: 64#; data: multi-point, sample once every 10 s, end in 1 min; rotation speed: 5 rpm;

[0077] (6) Install the rotor. Hold the upper part of the rotor connection with one hand and the rotor with the other hand, and gently screw it on. Note that the torque during rotor installation should not exceed ±30%. If this value is exceeded or "EEE" is displayed, immediately release the hand to prevent damage to the rotor;

[0078] (7) Immerse the rotor in the beaker (the rotor handle needs to be immersed in the paste);

[0079] (8) Start the measurement and record the data.

[0080] Protein determination method

[0081] (1) Digestion step: Weigh 0.8 - 1.6 g of the sample and put it into the digestion tube, add the composite catalyst K2SO4: C U SO4 (K2SO4: CuSO4 = 15:1), install the digestion device, then add 12 ml of concentrated sulfuric acid (press the bottle twice), cover the digestion lid, insert the water pipe, let water flow through, turn on the FOSS instrument, click start, heat up to 420 °C and digest for 2 h. After digestion, lift it up to cool down.

[0082] (2) Kjeldahl nitrogen analyzer: Install the digestion tube, turn on the switch, select the protein coefficient → input the sample weight → perform Kjeldahl nitrogen analysis for protein %.

[0083] Infrared analysis method

[0084] Take about 1 mg of the sample, mix it evenly with potassium bromide powder at a ratio of 1:200, and then press it into a tablet for infrared testing.

[0085] The infrared spectrum range is 400 - 4000 cm-1, and the resolution is 4 cm-1.

[0086] Materials

[0087] Sesame paste: Pure sesame paste retailed on the market;

[0088] Macroporous resin D101 type: Purchased from Sinopharm Chemical Reagent Co., Ltd.

[0089] Preparation Example 1

[0090] Degreasing: Weigh 200 g of commercially available sesame paste from Togo, and then extract it twice with n-hexane at room temperature (material-liquid ratio 1:2), each extraction for 4 h. Combine the filtrates and concentrate by vacuum rotary evaporation to obtain the n-hexane solvent layer component. The residue remaining after extraction with n-hexane is dried with hot air at 65 °C to remove the residual solvent, and a solid component is obtained.

[0091] Extraction: The solid component is extracted three times with 75% ethanol at room temperature (material-liquid ratio 1:3), each extraction for 4 h. Combine the filtrates and concentrate by vacuum rotary evaporation to obtain the alcohol-soluble component.

[0092] Extraction: Dissolve the alcohol-soluble component in water (material-liquid ratio 1:1), and then extract it three times with a 1:1 water-saturated n-butanol solution (1:1 deionized water ultrasonicated for 10 min, take the upper layer in a separating funnel). Combine the n-butanol extraction part, concentrate by vacuum rotary evaporation, and freeze-dry to obtain the n-butanol layer component.

[0093] Purification: Dissolve the n-butanol layer component in water (1:13), sonicate for 20 min to dissolve, and then transfer it all to a chromatography column. Then elute it with 95% edible ethanol respectively, the elution speed is 2 BV / h, and the elution volume is 750 mL (5 times the resin volume). Collect the eluate, concentrate by vacuum rotary evaporation, and freeze-dry to obtain the 95% ethanol extract.

[0094] Preparation Example 2

[0095] Degreasing: Follow the steps of Preparation Example 1.

[0096] Extraction: Follow the steps of Preparation Example 1.

[0097] Extraction: Follow the steps of Preparation Example 1.

[0098] Purification: The n-butanol layer components were dissolved in water (1:13), sonicated for 20 min for dissolution, then all transferred to a chromatography column, and then eluted with 90% edible ethanol respectively at an elution rate of 2 BV / h, and the eluate volume was 750 mL (5 times the resin volume). The eluate was collected, concentrated by vacuum rotary evaporation, and freeze-dried to obtain a 90% ethanol extract.

[0099] Preparation Example 3

[0100] Degreasing: According to the steps of Preparation Example 1;

[0101] Extraction: According to the steps of Preparation Example 1;

[0102] Extraction: According to the steps of Preparation Example 1;

[0103] Purification: The n-butanol layer components were dissolved in water (1:13), sonicated for 20 min for dissolution, then all transferred to a chromatography column, and then eluted with 85% edible ethanol respectively at an elution rate of 2 BV / h, and the eluate volume was 750 mL (5 times the resin volume). The eluate was collected, concentrated by vacuum rotary evaporation, and freeze-dried to obtain an 85% ethanol extract.

[0104] Preparation Example 4

[0105] Degreasing: According to the steps of Preparation Example 1;

[0106] Extraction: According to the steps of Preparation Example 1;

[0107] Extraction: According to the steps of Preparation Example 1;

[0108] Purification: The n-butanol layer components were dissolved in water (1:13), sonicated for 20 min for dissolution, then all transferred to a chromatography column, and then eluted with 100% edible ethanol respectively at an elution rate of 2 BV / h, and the eluate volume was 750 mL (5 times the resin volume). The eluate was collected, concentrated by vacuum rotary evaporation, and freeze-dried to obtain a 100% ethanol extract.

[0109] Preparation Example 5

[0110] Degreasing: According to the steps of Preparation Example 1;

[0111] Extraction: According to the steps of Preparation Example 1;

[0112] Extraction: According to the steps of Preparation Example 1;

[0113] Purification: The n-butanol layer components were dissolved in water (1:13), sonicated for 20 min for dissolution, then all transferred to a chromatography column, and then eluted with water respectively at an elution rate of 2 BV / h, and the eluate volume was 750 mL (5 times the resin volume). The eluate was collected, concentrated by vacuum rotary evaporation, and freeze-dried to obtain a water extract.

[0114] Preparation Example 6

[0115] Degreasing: Follow the steps of Preparation Example 1;

[0116] Extraction: Follow the steps of Preparation Example 1;

[0117] Extraction: Follow the steps of Preparation Example 1;

[0118] Purification: The n-butanol layer components were dissolved in water (1:13), sonicated for 20 min to dissolve, then all transferred to a chromatography column, and then eluted with 30% edible ethanol at an elution rate of 2 BV / h, and the eluate volume was 750 mL (5 times the resin volume). The eluate was collected, concentrated by vacuum rotary evaporation, and freeze-dried to obtain a 30% ethanol extract.

[0119] Preparation Example 7

[0120] Degreasing: Follow the steps of Preparation Example 1;

[0121] Extraction: Follow the steps of Preparation Example 1;

[0122] Extraction: Follow the steps of Preparation Example 1;

[0123] Purification: The n-butanol layer components were dissolved in water (1:13), sonicated for 20 min to dissolve, then all transferred to a chromatography column, and then eluted with 50% edible ethanol at an elution rate of 2 BV / h, and the eluate volume was 750 mL (5 times the resin volume). The eluate was collected, concentrated by vacuum rotary evaporation, and freeze-dried to obtain a 50% ethanol extract.

[0124] Preparation Example 8

[0125] Degreasing: Follow the steps of Preparation Example 1;

[0126] Extraction: Follow the steps of Preparation Example 1;

[0127] Extraction: Follow the steps of Preparation Example 1;

[0128] Purification: The n-butanol layer components were dissolved in water (1:13), sonicated for 20 min to dissolve, then all transferred to a chromatography column, and then eluted with 75% edible ethanol at an elution rate of 2 BV / h, and the eluate volume was 750 mL (5 times the resin volume). The eluate was collected, concentrated by vacuum rotary evaporation, and freeze-dried to obtain a 75% ethanol extract.

[0129] Example 1

[0130] 1 g of the 95% ethanol extract prepared in Preparation Example 1 was added to 100 g of pure sesame paste from Togo, and stirred evenly to obtain Sesame Paste 1.

[0131] Example 2

[0132] Add 1.5 g of the 95% ethanol extract prepared in Preparation Example 1 to 100 g of pure sesame paste from Togo, and stir evenly to obtain Sesame Paste 2.

[0133] Example 3

[0134] Add 2 g of the 95% ethanol extract prepared in Preparation Example 1 to 100 g of pure sesame paste from Togo, and stir evenly to obtain Sesame Paste 3.

[0135] Example 4

[0136] Add 3 g of the 95% ethanol extract prepared in Preparation Example 1 to 100 g of pure sesame paste from Togo, and stir evenly to obtain Sesame Paste 4.

[0137] Example 5

[0138] Add 2 g of the 90% ethanol extract prepared in Preparation Example 2 to 100 g of pure sesame paste from Togo, and stir evenly to obtain Sesame Paste 5.

[0139] Example 6

[0140] Add 2 g of the 85% ethanol extract prepared in Preparation Example 3 to 100 g of pure sesame paste from Togo, and stir evenly to obtain Sesame Paste 6.

[0141] Example 7

[0142] Add 2 g of the 100% ethanol extract prepared in Preparation Example 4 to 100 g of pure sesame paste from Togo, and stir evenly to obtain Sesame Paste 7.

[0143] Comparative Example 1

[0144] Pure sesame paste from Togo, designated as Sesame Paste 8.

[0145] Comparative Example 2

[0146] Add 3 g of the 75% ethanol extract prepared in Preparation Example 8 to 100 g of sesame paste, and stir evenly to obtain Sesame Paste 9.

[0147] Comparative Example 3

[0148] Add 3 g of the 50% ethanol extract prepared in Preparation Example 7 to 100 g of sesame paste, and stir evenly to obtain Sesame Paste 10.

[0149] Comparative Example 4

[0150] Add 3 g of the 30% ethanol extract prepared in Preparation Example 6 to 100 g of sesame paste, and stir evenly to obtain Sesame Paste 11.

[0151] Comparative Example 5

[0152] Add 3 g of the water extract prepared in Preparation Example 5 to 100 g of sesame paste and stir evenly to obtain Sesame Paste 12.

[0153] Protein content determination and infrared analysis

[0154] Protein assays were performed on the 5 different eluates obtained after purification in Example 1 and Comparative Examples 2-5, and the results are shown in Table 1.

[0155] Table 1: Eluted Extract Protein Content

[0156] Number Eluted Extract Protein Content Comparative Example 5 Water 8.75％ Comparative Example 4 30％ 15.20 Comparative Example 3 50％ 5.94％ Comparative Example 2 75％ 9.36 Example 1 95％ 7.30

[0157] As shown in Table 1, the protein in all extracts is in the range of 5.94 - 15.2%.

[0158] Infrared analysis was performed on the samples in Table 1 respectively, and the results are as Figures 1-5 shown. As Figures 1 to 5 shown, the main differences among the 5 extracts are the C-H stretching vibration at 3000 cm-1 and the characteristic peaks between 1000 - 2000 cm-1. Multiple C-H bond stretching vibrations will appear at 3000 wavenumbers during water extraction, which is consistent with 95% of the extracts and may be the characteristic peaks of some compounds with high polarity. Absorption peaks appear at around 1700 wavenumbers for all 5 extracts, which may be the characteristic peaks of the C=O double bond, except that the signal of the 30% extract is slightly weaker. The absorption peaks in the 1400 - 1600 wavenumber range for the 30 - 50% extracts and the 95% extracts should be the glycoside C-O bending vibrations, and those at 1000 - 1200 are the bending vibration peaks of some other C-H on the glycosidic bond, but there are slight differences in the 75% extract, which may be due to the influence of other substances on the bending vibration of the glycosidic bond. It is known in the art that soluble sugars and crude proteins have a positive effect on the storage stability of sesame paste, but the contents of both in the extracts of the present invention are relatively low. Therefore, the improvement of the stability of the sesame paste in this article is not entirely brought about by saccharide substances or crude proteins.

[0159] Centrifugal floating oil rate

[0160] Weigh 10.00 g of sesame paste and place it in a 150 mL centrifuge tube. Centrifuge at a rate of 8000 r / min for 5 min, weigh the upper floating oil, and record the weight as m1. Calculate the centrifugal floating oil rate using the following formula:

[0161] ES = (10.00 - m1 / 10.00) * 100%

[0162] where m1 is the mass of the upper floating oil.

[0163] Table 2: Detection results of sesame paste

[0164]

[0165]

[0166] The results show that after adding the extracts obtained by rotary evaporation of the ethanol eluates with high concentrations (such as 85%, 90%, 95% and 100%) to sesame paste, the viscosity of the sesame paste is greatly increased (the increase rate is 23.86 - 63.45%). In addition, the stability is also strongly improved, and the floating oil rate is reduced by 1.34 - 17.20%. However, adding water and the ethanol eluates with low concentrations (such as 30%, 50% and 75%) cannot change the viscosity and stability of sesame paste simultaneously.

Claims

1. A method for preparing a sesame extract, characterized in that, The method includes the steps of subjecting the degreased sesame raw material to alcohol extraction to obtain an alcohol-soluble component, extracting the alcohol-soluble component, and purifying the extracted component to obtain the sesame extract; wherein, in the purification step, purification is carried out using a resin and elution is carried out using an alcohol or an aqueous solution thereof, wherein the volume concentration of the aqueous solution of the alcohol is greater than or equal to 80%.

2. The preparation method according to claim 1, characterized in that, The purification is carried out using a styrene-type non-polar copolymer resin; Preferably, the solvent used for elution is an ethanol solution with a volume concentration of 85% - 100%, 90% - 95% or 80% - 95%; Preferably, the volume of the alcohol solution used for elution is 1 - 10 times the volume of the resin, preferably 3 - 7 times or 5 - 7 times; Preferably, the elution rate is 1 - 5 BV / h, preferably 1 - 3 BV / h.

3. The preparation method according to claim 1 or 2, characterized in that, The method has one or more of the following characteristics: The sesame raw material is selected from one or more of sesame seeds, sesame paste, sesame meal and sesame cake; The degreasing includes leaching with an organic solvent such as n-hexane to obtain an organic solvent layer, and removing the organic solvent in the organic solvent layer to obtain a solid component; The alcohol extraction uses an alcohol solution to leach the solid component obtained in the degreasing step to obtain an alcohol-soluble component; preferably, the alcohol is ethanol; preferably, the volume concentration of the alcohol in the aqueous solution of the alcohol is 20% - 80%, preferably 70 ± 10%; The extraction includes using n-butanol to extract the alcohol-soluble component dissolved in water to obtain an n-butanol layer component; preferably, the volume ratio of the alcohol-soluble component to water is 1:(1 - 3), such as 1:1; preferably, the n-butanol is a water-saturated n-butanol solution, more preferably a 1:1 water-saturated n-butanol solution.

4. The preparation method according to claim 1 or 2, characterized in that, The method includes: Degreasing: Leaching sesame paste with n-hexane several times, combining the filtrates obtained each time, and removing n-hexane to obtain a solid component; Alcohol extraction: Leaching the solid component with an ethanol solution with a volume concentration of 70 ± 10% several times, combining the filtrates obtained each time, and removing the solvent to obtain an alcohol-soluble component; Extraction: Dissolving the alcohol-soluble component in water, extracting with a 1:1 water-saturated n-butanol solution several times, combining the n-butanol extraction parts obtained each time, removing n-butanol, and drying to obtain an n-butanol layer component; and Purification: Dissolving the n-butanol layer component in water, transferring it to a chromatography column filled with a styrene-type non-polar copolymer resin, eluting with an ethanol solution with a volume concentration of 85 - 100%, the elution rate is 1 - 5 BV / h, the volume of the alcohol solution used for elution is 3 - 7 times the volume of the resin, collecting the eluate, removing the solvent, and drying to obtain the sesame extract.

5. The sesame extract prepared by the method according to any one of claims 1 - 4; preferably, the protein content of the sesame extract is ≤10%.

6. A method for increasing the viscosity and / or stability of sesame paste, the method comprising adding the sesame extract or its aqueous solution according to claim 4 to the sauce for preparing sesame paste during the preparation of sesame paste, and the step of preparing sesame paste from the sauce added with the sesame paste extract; wherein, The amount of the added sesame extract is more than 1% by weight of the sauce, preferably 1 - 3%, more preferably 1.5 - 2%.

7. The method according to claim 6, characterized in that The method further includes the step of preparing the sesame extract according to any one of claims 1 - 4.

8. A sauce containing more than 1% by weight of the sesame extract according to claim 5, preferably 1 - 3%, more preferably 1.5 - 2%; Preferably, the viscosity of the sauce ≥ 10,000 CP.S, preferably ≥ 11,000 CP.S, more preferably ≥ 13,000 CP.S; Preferably, the centrifugal floating oil rate of the sauce ≤ 18.3%; Preferably, the sauce is sesame paste.

9. The application of the method according to any one of claims 1 to 4 and / or the sesame extract according to claim 5 in enhancing the viscosity and / or stability of the sauce; preferably, the sauce is sesame paste.

10. A food product, which contains the sesame extract according to claim 5 or the sauce according to claim 8.

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