Sesame paste with low bitter taste and preparation method thereof

Abstract

The invention mainly relates to the technical field of food seasoning sauce processing, in particular to low-bitterness sesame paste and a preparation method thereof. Specifically, the invention provides a method for reducing the bitter taste of sesame cakes or sesame meal, the method comprises the step of carrying out alcohol extraction on sesame cakes or sesame meal separated from sesame oil in the sesame oil preparation process, and alcohol extraction is carried out by using an alcohol solution with the concentration of 20-80%. The invention also provides the sesame product prepared by the method and application of the sesame product. According to the invention, substances influencing the bitter taste in the sesame paste are found, and the substances in the sesame paste are removed to obtain the recovered sesame paste, so that the bitter taste of the sesame paste can be remarkably reduced; the specific sesame extract is added into the recovered sesame paste, so that the bitter taste of the sesame paste can be further reduced.

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 with low bitterness 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 herbaceous plant. At present, the main sesame processed products in China include sesame oil, sesame paste, peeled sesame, and roasted sesame, etc. Among them, sesame paste is a food made by grinding sesame after high-temperature roasting. It is a colloidal suspension mainly composed of hydrophilic solid suspensions suspended in sesame oil. Sesame paste food has health care effects such as antibacterial, regulating blood lipids, stabilizing blood pressure, and protecting the liver. In the Mediterranean, Middle East, and East Asian regions, sesame paste is widely used in various cuisines due to its unique nutty flavor and high nutritional content, and is a popular ingredient. In Central China, North China and other places, unique delicacies have been created based on sesame paste, and it can be found in Wuhan's hot dry noodles, cold noodle sheets, and sesame paste hot pot.

[0003] The bitterness of sesame paste will bring some unpleasant experiences to consumers. Bitterness is one of the basic flavors in the application of sesame paste in cooking. If the bitterness is particularly strong, it will limit the use of some consumers. Although in the past few decades, bitter compounds in many foods such as coffee, beer, tea, olive oil, whole wheat bread, and pea protein isolate have been comprehensively elaborated, there are few identification studies on bitter compounds in sesame and its products. So far, only by peeling or adding external bitterness masking agents can the bitterness of sesame paste be reduced, but the main bitter components in sesame paste are still unclear. Summary of the Invention

[0004] The present invention provides a method for reducing the bitterness of sesame cake or sesame meal, the method comprising the step of subjecting the sesame cake or sesame meal to alcohol extraction; wherein, the bitterness of the sesame cake or sesame meal obtained after alcohol extraction is reduced relative to that before alcohol extraction; wherein, an alcohol solution with a concentration of 20% - 80%, preferably 70% ± 10% is used for alcohol extraction.

[0005] In one or more embodiments, in the alcohol extraction step, the alcohol solution is an aqueous solution of alcohol, preferably an aqueous solution of ethanol.

[0006] In one or more embodiments, during alcohol extraction, the mass of the alcohol solution is 1 - 5 times, such as 2 - 4 times that of the sesame cake or sesame meal.

[0007] In one or more embodiments, the sesame cake or sesame meal is extracted with the alcohol solution 1 - 3 times.

[0008] In one or more embodiments, the extraction time for each extraction is more than 0.5h, such as 1 - 8h or 2 - 5h.

[0009] In one or more embodiments, the sesame cake or sesame meal is obtained from the sesame cake or sesame meal separated from sesame oil during the preparation of sesame oil.

[0010] The present invention also provides a method for reducing the bitterness of sesame paste, which method comprises the steps of mixing sesame cake or sesame meal and sesame oil to obtain a mixture, and using the mixture to prepare sesame paste; wherein, the sesame cake or sesame meal is selected from the sesame cake or sesame meal obtained by the method for reducing the bitterness of sesame cake or sesame meal described in any one of the embodiments herein and the alcohol-insoluble component obtained by degreasing and alcohol extraction of sesame paste.

[0011] In one or more embodiments, the method comprises the steps of mixing a sesame extract with the sesame cake or sesame meal and sesame oil to obtain a mixture, and using the mixture to prepare sesame paste; wherein, the sesame extract is obtained from the alcohol-soluble component obtained by alcohol extraction of the sesame cake or sesame meal through extraction and purification; preferably, the alcohol extraction is as described in any one of the embodiments herein.

[0012] In one or more embodiments, the extraction has one or more of the following characteristics:

[0013] (1) Before extraction, the alcohol-soluble component is dissolved in water; preferably, the volume ratio of the alcohol-soluble component to water is 1:(1 - 3), such as 1:1;

[0014] (2) Extracted with n-butanol, preferably using a 1:1 water-saturated n-butanol solution;

[0015] (3) During the extraction process, ultrasound is applied to promote dissolution;

[0016] (4) The number of extractions is 1 - 5 times, and the extraction time for each time is 10 min - 1 h;

[0017] (5) The method further comprises concentrating the n-butanol extraction part to obtain an n-butanol layer component; and

[0018] (6) The method further comprises, after the extraction is completed, concentrating and drying the n-butanol layer component.

[0019] In one or more embodiments, the purification has one or more of the following characteristics:

[0020] (1) Purified with resin; preferably, the resin is a non-polar resin, preferably a styrene-type non-polar copolymer resin;

[0021] (2) Eluted with water and / or an aqueous solution of alcohol; wherein, the volume concentration of the aqueous solution of alcohol is less than or equal to 20% and / or greater than or equal to 80%, preferably 0 - 10% and / or 80 - 95%;

[0022] (3) During elution, the volume of the aqueous solution of the alcohol is 1 to 10 times the volume of the resin, such as 3 to 7 times or 5 to 7 times;

[0023] (4) The elution rate is 1 to 5 BV / h or 1 to 3 BV / h; and

[0024] (5) The purification further includes concentration and drying. Preferably, the concentration is by vacuum rotary evaporation concentration, and preferably, the drying is by freeze-drying.

[0025] The present invention also provides a sesame product obtained by the method according to any one of the embodiments herein; preferably, the sesame product is sesame paste.

[0026] The present invention also provides the application of the alcohol extraction method in reducing the bitterness of sesame raw materials. The alcohol extraction method includes subjecting sesame raw materials to alcohol extraction. The sesame raw materials are selected from one or more of sesame seeds, sesame paste, sesame cake or sesame meal; wherein, the volume concentration of alcohol in the alcohol solution used for extraction is 20% to 80%, preferably 70% ± 10%.

[0027] In one or more embodiments, the alcohol extraction has one or more of the following characteristics:

[0028] The alcohol used for extraction is preferably ethanol;

[0029] During alcohol extraction, the mass of the alcohol solution is 1 to 5 times that of the solid component, such as 2 to 4 times;

[0030] The extraction is carried out 1 to 3 times; and

[0031] The time for each extraction is more than 0.5 h, such as 1 to 8 h or 2 to 5 h.

[0032] The present invention also provides the application of the water eluate, the alcohol eluate below 20%, and / or the alcohol eluate above 80% of sesame paste in reducing the bitterness of the sesame paste; wherein: the eluate is the eluate obtained by subjecting sesame paste to alcohol extraction to obtain an alcohol-soluble component and then extracting and purifying the alcohol-soluble component.

[0033] In one or more embodiments, the sesame paste is degreased prior to alcohol extraction.

[0034] In one or more embodiments, in the extraction step, n-butanol is used for extraction.

[0035] In one or more embodiments, in the purification step, purification is carried out with resin, and elution is carried out with water and / or an aqueous solution of alcohol. The volume concentration of the aqueous solution of alcohol is less than or equal to 20% and / or greater than or equal to 80%.

[0036] In one or more embodiments, the resin is a non-polar resin, preferably a styrene-type non-polar copolymer resin, such as macroporous resin. Detailed Description

[0037] As used herein, the terms "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 term "paste" refers to the part remaining after removing water from conventional sauces. 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] As used herein, for the sake of brevity of description, all possible combinations of all technical features in each embodiment or example are not described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered to be within the scope described in this specification.

[0042] In the prior art, in order to reduce the bitterness of sesame paste, a lot of foreign substances are added, but the added foreign substances affect the purity and flavor of sesame paste. After in-depth research, the present inventors found the substances causing bitterness in sesame meal or sesame cake, and the bitterness of the sesame paste prepared from the sesame cake or sesame meal from which the bitter substances have been removed and sesame oil is reduced. The inventors also found that adding a specific sesame extract during the preparation of sesame paste can further reduce the bitterness of sesame paste.

[0043] Therefore, the present invention provides a method for reducing the bitterness of sesame cake or sesame meal, the method comprising the step of subjecting the sesame cake or sesame meal to alcohol extraction; wherein, an alcohol solution with a concentration of 20% - 80%, preferably 70% ± 10% is used for alcohol extraction. The bitterness of the sesame cake or sesame meal obtained after alcohol extraction is reduced compared with that before alcohol extraction.

[0044] In this text, the alcohol used for alcohol 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 50% to 80% or 70 ± 10%. In some embodiments, an aqueous solution of ethanol with a volume concentration of 70 to 80% is used for alcohol extraction (leaching). 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 leaching times are related to the amount of the product obtained by extraction. Therefore, those skilled in the art can select one or more than two leaching times and the leaching time for each time according to the actual situation. For example, the leaching time for each time can be more than 0.5 h, such as 1 to 8 h or 2 to 5 h. After the leaching is completed, the alcohol and water in the filtrate can be removed, and the filtrate can be concentrated to obtain an alcohol-soluble component and an alcohol-insoluble component. This alcohol-insoluble component is the sesame cake or sesame meal with reduced bitterness.

[0045] In this text, the sesame cake / sesame meal used for alcohol extraction can be the sesame cake / sesame meal obtained during the conventional preparation of sesame oil, or the sesame cake / sesame meal obtained after removing oil from sesame paste, or a mixture of any proportion thereof.

[0046] Conventional methods for preparing sesame oil include pressing methods (such as cold pressing or hot pressing), water displacement method, leaching method, etc. After separating the oil from the residue, the separated residue is the sesame cake / sesame meal used in the above method in this text. When needed, the residue can be defatted to remove as much of the remaining oil part as possible.

[0047] When the sesame cake / sesame meal is from sesame paste, the sesame paste can be defatted, that is, the oil part and the solid part in the sesame paste are separated, and this solid part is the sesame cake / sesame meal to be reduced in bitterness in the above method in this text.

[0048] The degreasing step can be implemented by using degreasing methods well-known in the art. For example, sesame raw materials can be extracted with an organic solvent such as n-hexane to obtain the components (oil components in sesame) dissolved in the organic solvent (such as n-hexane) present in sesame, as well as the solid insoluble component in sesame that is insoluble in the used organic solvent. In this article, the sesame raw material 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 extract with an organic solvent such as n-hexane. In some embodiments, the present application uses pure sesame paste as the sesame raw material for organic solvent extraction. It should be understood that the length and number of extractions are related to the amount of the obtained product. Therefore, 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 material can be extracted with an organic solvent more than once, such as 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 1 to 8 h, such as 2 to 8 h or 2 to 5 h. When extracting, 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. For multiple extractions, the filtrate parts obtained each time can be combined. After the extraction is completed, for the components dissolved in the organic solvent, the filtrate can be concentrated by, for example, vacuum rotary evaporation to further remove the residual organic solvent in the filtrate to obtain the solid form of the components dissolved in the organic solvent; for the solid insoluble component insoluble in the organic solvent, the residual organic solvent can be removed by heating and drying to obtain the solid component (i.e., the sesame cake / meal to be de-bittered). The drying can be hot air drying. The drying temperature can be 50 to 80 °C, preferably 60 to 70 °C. In this article, the sesame oil obtained in the degreasing step can be used to prepare the sesame paste of the present invention.

[0049] After mixing the sesame cake or meal with reduced bitterness with sesame oil and grinding it into a paste, a sesame paste with reduced or decreased bitterness can be prepared. The sesame cake / meal and sesame oil can be determined according to the ratio of the solid part to the oil part in conventional sesame paste. For example, the mixing mass ratio of the sesame cake / meal to sesame oil is usually (1 to 5):1, preferably (1 to 3):1. In this article, the grinding into a paste can be carried out using techniques well-known in the art. Conventional graphite or mechanical grinding can be used for grinding into a paste.

[0050] The inventors also found that the product obtained after further extraction and purification of the alcohol-soluble components obtained in the above alcohol extraction step (i.e., the sesame extract described herein), when jointly preparing sesame paste with the sesame cake / meal with reduced bitterness and sesame oil, the prepared sesame paste has further reduced bitterness compared with the sesame paste prepared only with the sesame cake / meal with reduced bitterness and sesame oil.

[0051] Therefore, the method for preparing the sesame paste with reduced bitterness described in this article further includes the steps of mixing the sesame extract with the sesame cake / sesame meal with reduced bitterness and sesame oil, and grinding them into a paste. The addition amount of the sesame extract can be determined according to the actual situation of bitterness reduction in the sesame paste. For example, when the bitterness reduction is not obvious, the amount of the sesame extract can be appropriately increased; when the effect of bitterness reduction is obvious, the addition amount of the sesame extract can be appropriately reduced. In an exemplary embodiment, based on the total weight of the sesame paste, the dosage of the sesame extract is 0.01-5%, preferably 0.01-2% or 0.01-1%.

[0052] In the extraction step of this article, the alcohol-soluble component can be first dissolved in water, and then extracted with n-butanol to obtain the n-butanol component. The volume ratio of the alcohol-soluble component to water can be 1:(1-3), 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 of extractions and the length of time are related to the amount of the product obtained by extraction. Therefore, those skilled in the art can select the appropriate number of extractions and time according to the actual situation. For example, the number of extractions can be 1-5 times, and the time for each extraction can be 10 min-1 h. The n-butanol extraction part can be concentrated to obtain the 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.

[0053] In the purification step of the present invention, the n-butanol layer component can be first dissolved in water, and the sesame extract described in the present invention can be obtained by resin separation and purification. 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 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 less than or equal to 20% and / or greater than or equal to 80%, such as 0% (water elution), 10%, 15%, 90%, 95%. 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 to 5 BV / h, preferably 1 to 3 BV / h. During the elution process, the eluate is collected, concentrated, and dried, and the sesame extract of the present application can be obtained, including water eluate, alcohol eluate below 20%, and / or alcohol eluate above 80%. 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.

[0054] Therefore, in some embodiments, the present invention provides a method for reducing the bitterness of sesame paste, which method includes the step of mixing sesame cake or sesame meal treated by alcohol extraction and sesame oil to prepare sesame paste.

[0055] In some embodiments, the present invention provides a method for reducing the bitterness of sesame paste or a method for preparing sesame paste with reduced bitterness, which method includes separating sesame oil and sesame cake or sesame meal (i.e., defatting step) from sesame paste, performing alcohol extraction on the sesame cake or sesame meal to obtain an alcohol-insoluble component, mixing the sesame oil and the alcohol-insoluble component, and grinding to prepare sesame paste with reduced bitterness. This sesame paste has reduced bitterness compared to the original sesame paste. Among them, the defatting and alcohol extraction are as described in any of the previous embodiments. Further, the method further includes the step of mixing the sesame extract described in any of the embodiments of the present invention, the sesame oil, and the alcohol-insoluble component, and grinding the resulting mixture.

[0056] In some embodiments, the present invention also provides the use of water eluate, alcohol eluate below 20%, and / or alcohol eluate above 80% in reducing the bitterness of sesame paste. The preparation methods of the water eluate, alcohol eluate below 20%, and alcohol eluate above 80% are as described in any of the embodiments of the present invention.

[0057] In some embodiments, the present invention provides a sesame extract, and the components contained therein are substantially the same as those of the sesame extract prepared by the preparation method of the sesame extract described herein. "Substantially the same" as described herein means that among the components contained in the sesame extract, the components accounting for more than 10%, preferably more than 20%, and more preferably more than 30% of the total weight of the sesame extract are completely the same.

[0058] In some embodiments, the present invention further provides a sesame paste, which contains: the product obtained by grinding the sesame cake or sesame meal with reduced bitterness described herein and sesame oil, and optionally also contains the sesame extract described herein; preferably, the mass ratio of the sesame cake or sesame meal to the sesame oil is (1 to 5):1, preferably (1 to 3):1; preferably, in the sesame paste, the content of the sesame extract is 7.0 to 40.0 wt%. Preferably, the sesame paste is prepared by the method described in any of the embodiments herein.

[0059] In some embodiments, the present invention further provides a mixed sauce, which contains the sauce with reduced bitterness described above.

[0060] The present invention further provides a food, which contains the sesame paste or the mixed sauce described herein.

[0061] The present invention has the following beneficial effects:

[0062] The present invention discovers a sesame extract. Removing this extract from the sesame paste can reduce the bitterness of the sesame paste.

[0063] The present invention will be further described below by way of specific examples. It should be understood that these examples are merely illustrative and not intended to limit the scope of the present invention. The methods and reagents used in the examples are conventional methods and reagents in the art unless otherwise specified.

[0064] Materials

[0065] Sesame paste: Pure sesame paste retailed on the market;

[0066] Macroporous resin: D101 type macroporous resin, sourced from Sinopharm Chemical Reagent Co., Ltd.

[0067] Protein testing method

[0068] Digestion step: Weigh 0.8 - 1 g (6 g) of the sample and put it into the digestion tube. Add the composite catalyst K2SO4:CuSO4 (K2SO4:CuSO4 = 15:1). Assemble 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, start the electron microscope, heat up to 420 °C and digest for 2 h. After digestion, lift it up to cool down.

[0069] Kjeldahl nitrogen analyzer: Assemble the digestion tube, click the switch, select the protein coefficient → input the sample weight → perform Kjeldahl nitrogen analysis for protein %.

[0070] Preparation Example 1

[0071] Degreasing: Weigh 200 g of sesame paste, and then extract it twice at room temperature with n - hexane (solid - 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 (sesame oil). The residue remaining after n - hexane extraction is dried at 65 °C in hot air to remove the residual solvent, and a solid component is obtained.

[0072] Extraction: The solid component is extracted three times at room temperature with ethanol (80% concentration) (solid - liquid ratio 1:3), each extraction for 4 h. Combine the filtrates and concentrate by vacuum rotary evaporation to obtain the alcohol - soluble component; the residue remaining after ethanol extraction is dried at 65 °C in hot air to remove the residual solvent, and an alcohol - insoluble component (sesame meal) is obtained.

[0073] Extraction: Dissolve the alcohol - soluble component in water (solid - liquid ratio 1:1), then extract it three times with a 1:1 water - saturated n - butanol solution (ultrasonic in 1:1 deionized water for 10 min, take the upper layer in a separatory funnel). Combine the n - butanol extraction parts, concentrate by vacuum rotary evaporation, and freeze - dry to obtain the n - butanol layer component.

[0074] Purification: Dissolve the n - butanol layer component in water (1:13), ultrasonic for 20 min to dissolve, then transfer all of it to a chromatography column, and then elute with water respectively at an elution speed of 2 BV / h and an elution volume of 750 mL (5 times the resin volume). Collect the eluate, concentrate by vacuum rotary evaporation, and freeze - dry to obtain the water extract.

[0075] Preparation Example 2

[0076] Degreasing: Follow the steps of Preparation Example 1

[0077] Extraction: Follow the steps of Preparation Example 1

[0078] Extraction: Follow the steps of Preparation Example 1

[0079] 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 95% 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 the extract eluted with 95% ethanol.

[0080] Preparation Example 3

[0081] Degreasing: According to the steps of Preparation Example 1

[0082] Extraction: According to the steps of Preparation Example 1

[0083] Extraction: According to the steps of Preparation Example 1

[0084] 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 80% 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 the extract eluted with 80% ethanol.

[0085] Preparation Example 4

[0086] Degreasing: According to the steps of Preparation Example 1

[0087] Extraction: According to the steps of Preparation Example 1

[0088] Extraction: According to the steps of Preparation Example 1

[0089] 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 75% 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 the extract eluted with 75% ethanol.

[0090] Preparation Example 5

[0091] Degreasing: According to the steps of Preparation Example 1

[0092] Extraction: According to the steps of Preparation Example 1

[0093] Extraction: According to the steps of Preparation Example 1

[0094] 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 50% 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 the extract eluted with 50% ethanol.

[0095] Preparation Example 6

[0096] Degreasing: Follow the steps of Preparation Example 1

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

[0098] Extraction: Follow the steps of Preparation Example 1

[0099] Purification: The components in the n-butanol layer were dissolved in water (1:13), dissolved by ultrasonic for 20 min, then all transferred to a chromatography column, and then eluted with 30% 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 the extract eluted with 30% ethanol.

[0100] Preparation Example 7

[0101] Degreasing: Follow the steps of Preparation Example 1

[0102] Extraction: Follow the steps of Preparation Example 1

[0103] Extraction: Follow the steps of Preparation Example 1

[0104] Purification: The components in the n-butanol layer were dissolved in water (1:13), dissolved by ultrasonic for 20 min, then all transferred to a chromatography column, and then eluted with 20% 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 the extract eluted with 20% ethanol.

[0105] Example 1

[0106] 1.03 g of the water extract prepared in Preparation Example 1 was added to 70 g of sesame meal (the alcohol-insoluble component obtained in Preparation Example 1), and then 50 g of sesame oil (the n-hexane layer obtained in Preparation Example 1) was added, and physically mixed evenly, and then ground into sesame paste 1 with a stone mill, and the sesame paste was subjected to a bitter taste sensory evaluation.

[0107] Example 2

[0108] 0.048 g of the extract eluted with 95% ethanol obtained in Preparation Example 2 was added to 70 g of sesame meal (the alcohol-insoluble component obtained in Preparation Example 2), and then 50 g of sesame oil (the n-hexane layer obtained in Preparation Example 2) was added, and then ground into sesame paste 2 with a stone mill, and the sesame paste was subjected to a bitter taste sensory evaluation.

[0109] Example 3

[0110] 1.032 g of the water extract obtained in Preparation Example 1 and 0.048 g of the extract obtained by eluting with 95% ethanol in Preparation Example 2 (the mass ratio of the two is 1:1) were added to 70 g of sesame meal (the alcohol-insoluble component in the extraction step of Preparation Example 1), and then 50 g of sesame oil (the n-hexane layer in the defatting step of Preparation Example 1) was added. After physical mixing evenly, it was ground into sesame paste 3 with a stone mill, and the bitter taste of the sesame paste was evaluated sensorially.

[0111] Example 4

[0112] 0.144 g of the extract obtained by eluting with 80% ethanol in Preparation Example 3 was added to 70 g of sesame meal (the alcohol-insoluble component obtained in Preparation Example 2), and then 50 g of sesame oil (the n-hexane layer obtained in Preparation Example 2) was added. Then it was ground into sesame paste 4 with a stone mill, and the bitter taste of the sesame paste was evaluated sensorially.

[0113] Example 5

[0114] 0.36 g of the extract obtained by eluting with 20% ethanol in Preparation Example 7 was added to 70 g of sesame meal (the alcohol-insoluble component obtained in Preparation Example 2), and then 50 g of sesame oil (the n-hexane layer obtained in Preparation Example 2) was added. Then it was ground into sesame paste 5 with a stone mill, and the bitter taste of the sesame paste was evaluated sensorially.

[0115] Comparative Example 1

[0116] 0.276 g of the extract obtained by eluting with 30% ethanol in Preparation Example 6 was added to 70 g of sesame meal (the alcohol-insoluble component obtained in Preparation Example 6), and then 50 g of sesame oil (the n-hexane layer obtained in Preparation Example 6) was added. After physical mixing evenly, it was ground into sesame paste 6 with a stone mill, and the bitter taste of the sesame paste was evaluated sensorially.

[0117] Comparative Example 2

[0118] 0.48 g of the extract obtained by eluting with 50% ethanol in Preparation Example 5 was added to 70 g of sesame meal (the alcohol-insoluble component obtained in Preparation Example 5), and then 50 g of sesame oil (the n-hexane layer obtained in Preparation Example 5) was added. After physical mixing evenly, it was ground into sesame paste 7 with a stone mill, and the bitter taste of the sesame paste was evaluated sensorially.

[0119] Comparative Example 3

[0120] 0.156 g of the extract obtained by eluting with 75% ethanol in Preparation Example 4 was added to 70 g of sesame meal (the alcohol-insoluble component obtained in Preparation Example 4), and then 50 g of sesame oil (the n-hexane layer obtained in Preparation Example 4) was added. After physical mixing evenly, it was ground into sesame paste 8 with a stone mill, and the bitter taste of the sesame paste was evaluated sensorially.

[0121] Comparative Example 4

[0122] 0.276 g of the extract obtained by eluting with 30% ethanol in Preparation Example 6, 0.48 g of the extract obtained by eluting with 50% ethanol in Preparation Example 5, and 0.156 g of the extract obtained by eluting with 75% ethanol in Preparation Example 4 (the mass ratio of the three is 1:1:1) were added to 70 g of sesame meal (the alcohol-insoluble component in the extraction step of Preparation Example 1), and then 50 g of sesame oil (the n-hexane layer in the defatting step of Preparation Example 1) was added. After physical mixing evenly, it was ground into sesame paste 9 with a stone mill, and the bitterness sensory evaluation of the sesame paste was carried out.

[0123] Comparative Example 5

[0124] Sesame paste 10: Commercially available sesame paste.

[0125] The bitterness sensory evaluation of sesame paste 10 was directly carried out.

[0126] Comparative Example 6 (without extract)

[0127] 50 g of sesame oil (the n-hexane layer in the defatting step of Preparation Example 1) was added to 70 g of sesame meal (the alcohol-insoluble component in the extraction step of Preparation Example 1). After physical mixing evenly, it was ground into sesame paste 11 with a stone mill, and the bitterness sensory evaluation of the sesame paste was carried out.

[0128] Bitterness sensory

[0129] Professional evaluators (15 sensory evaluators) of the bitterness sensory panel trained for 1 year carried out bitterness ranking. The bitterness score was 1-7, and the larger the value, the higher the bitterness. A score of 1-2 indicates not bitter, a score of 3-4 indicates relatively bitter (excluding 4), a score of 4-5 indicates bitter, and a score of 6-7 indicates very bitter. The sensory test results are shown in the following table.

[0130] Table 1: Bitterness test results

[0131]

[0132]

[0133] Note: "√" indicates containing; Sesame paste 10 substantially contains all component extracts itself.

[0134] As can be seen from the above table, after removing 30-75% ethanol extracts from the sesame paste (Examples 1-5), the bitterness sensory of the sesame paste was significantly reduced, and a sesame paste with lower bitterness could be effectively prepared; after removing all concentration ethanol extracts from the sesame paste (Example 6), the bitterness of the sesame paste could also be reduced to a certain extent.

[0135] The prior art shows that the bitter substances in sesame oil come from protein short peptides. Therefore, the inventor used a Kjeldahl nitrogen analyzer to titrate the protein content of the extract. As shown in the following table, the results show that the protein content of the 30-75% ethanol extract that causes bitterness in sesame paste is in the range of 5.94-15.2%, with high and low protein contents; while the protein contents of the water extract and the 95% ethanol extract are also in this range, but they do not cause bitterness in sesame paste. It can be seen that regardless of the high or low protein content, the extract of the present invention will not cause bitterness in sesame paste. Therefore, the source of bitterness of the extract of the present invention is not protein short peptides.

[0136] Table 2: Protein content of eluted extract

[0137] Preparation Example Eluted Extract Protein Content 1 Water 8.75％ 6 30％ 15.20％ 5 50％ 5.94％ 4 75％ 9.36％ 2 95％ 7.30％

Claims

1. A method for reducing the bitterness of sesame cake or sesame meal, characterized in that, The method includes the step of performing alcohol extraction on sesame cake or sesame meal; Among them, the bitterness of the sesame cake or sesame meal obtained after alcohol extraction is reduced compared to before alcohol extraction; Among them, an alcohol solution with a concentration of 20% - 80%, preferably 70% ± 10% is used for alcohol extraction.

2. The method according to claim 1, characterized in that, The alcohol extraction step has one or more of the following characteristics: The alcohol solution is an aqueous solution of alcohol, preferably an aqueous solution of ethanol; During alcohol extraction, the mass of the alcohol solution is 1 - 5 times, such as 2 - 4 times, that of the sesame cake or sesame meal; The alcohol solution is used for leaching 1 - 3 times; and The time for each leaching is more than 0.5h, such as 1 - 8h or 2 - 5h.

3. The method according to claim 1 or 2, characterized in that, The sesame cake or sesame meal is from the sesame cake or sesame meal obtained after being separated from sesame oil during the preparation process of sesame oil.

4. A method for reducing the bitterness of sesame paste, characterized in that, The method includes the steps of mixing sesame cake or sesame meal and sesame oil to obtain a mixture, and using the mixture to prepare sesame paste; Among them, the sesame cake or sesame meal is selected from the sesame cake or sesame meal obtained by the method described in any one of claims 1 - 3 and the alcohol-insoluble component obtained after degreasing and alcohol extraction of sesame paste.

5. The method according to claim 4, wherein The method includes the steps of mixing sesame extract with the sesame cake or sesame meal and sesame oil to obtain a mixture, and using the mixture to prepare sesame paste; Among them, the sesame extract is obtained by extracting and purifying the alcohol-soluble component obtained by alcohol extraction of the sesame cake or sesame meal; preferably, the alcohol extraction is as described in claim 1 or 2.

6. The method according to claim 5, wherein: The extraction has one or more of the following characteristics: (1) Before extraction, the alcohol-soluble component is dissolved in water; preferably, the volume ratio of the alcohol-soluble component to water is 1:(1 - 3), such as 1:1; (2) Extract with n-butanol, preferably use a 1:1 water-saturated n-butanol solution; (3) During the extraction process, ultrasound is applied to promote dissolution; (4) The number of extractions is 1 - 5 times, and the time for each extraction is 10min - 1h; (5) The method further includes concentrating the n-butanol extraction part to obtain an n-butanol layer component; and (6) After the extraction is completed, the method further includes concentrating and drying the n-butanol layer component; The purification has one or more of the following characteristics: (1) Purify with resin; preferably, the resin is a non-polar resin, preferably a styrene-type non-polar copolymer resin; (2) Elute with water and / or an aqueous solution of alcohol; among them, the volume concentration of the aqueous solution of alcohol is less than or equal to 20% and / or greater than or equal to 80%, preferably 0 - 10% and / or 80 - 95%; (3) During elution, the volume of the aqueous solution of alcohol is 1 - 10 times, such as 3 - 7 times or 5 - 7 times, that of the resin volume; (4) The elution speed is 1 - 5BV / h or 1 - 3BV / h; and (5) The purification further includes concentration and drying, preferably, the concentration is vacuum rotary evaporation concentration, and preferably, the drying is freeze-drying.

7. A sesame product obtained by the method according to any one of claims 1 - 6; preferably, the sesame product is sesame paste.

8. Use of the alcohol extraction method in reducing the bitterness of sesame raw materials, characterized in that, The alcohol extraction method includes alcohol extraction of sesame raw materials, and the sesame raw materials are selected from one or more of sesame seeds, sesame paste, sesame cake or sesame meal; wherein, the volume concentration of alcohol in the alcohol solution used for extraction is 20% to 80%, preferably 70% ± 10%.

9. The application according to claim 8, wherein The alcohol extraction has one or more of the following characteristics: The alcohol used for extraction is preferably ethanol; During alcohol extraction, the mass of the alcohol solution is 1 to 5 times, such as 2 to 4 times, that of the solid component; The extraction is carried out 1 to 3 times; and The time for each extraction is more than 0.5 h, such as 1 to 8 h or 2 to 5 h.

10. Application of the water eluate, alcohol eluate below 20%, and / or alcohol eluate above 80% of sesame paste in reducing the bitterness of the sesame paste; wherein: The eluate is the eluate obtained by alcohol extraction of sesame paste to obtain an alcohol-soluble component and then extracting and purifying the alcohol-soluble component; preferably, the sesame paste is degreased before alcohol extraction; In the extraction step, n-butanol is used for extraction; In the purification step, purification is carried out with resin, and elution is carried out with water and / or an aqueous solution of alcohol, and the volume concentration of the aqueous solution of alcohol is less than or equal to 20% and / or greater than or equal to 80%; Preferably, the resin is a non-polar resin, preferably a styrene-type non-polar copolymer resin, such as macroporous resin.

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