Zanthoxylum bungeanum flavor shortening based on enzymatic transesterification and preparation method of zanthoxylum bungeanum flavor shortening

Abstract

The invention discloses zanthoxylum bungeanum flavor shortening based on enzymatic transesterification. The shortening comprises 25-45 parts of palm oil stearin; 25 to 45 parts of shea butter; 15 to 25 parts of soybean oil; 5-15 parts of zanthoxylum oil; the invention relates to a catalyst lipase for enzymatic transesterification. The invention also discloses a preparation method of the shortening, which comprises the following steps: respectively preheating the palm oil stearin, the shea butter, the soybean oil and the zanthoxylum oil according to the formula ratio at 65-75 DEG C, adding lipase for rotary evaporation after preheating, controlling the rotating speed at 180-220r / min, and reacting for 3-5 hours to complete the transesterification process; and then removing the lipase to terminate the reaction. According to the invention, palm oil stearin, shea butter and soybean oil are taken as substrates through an enzymatic ester exchange technology, zanthoxylum oil is innovatively introduced, and a novel shortening system with regional flavor is successfully developed. The acid value of the pepper-flavored shortening disclosed by the invention is between 0.2 mg / g and 0.5 mg / g, the peroxide value is between 0.05 g / 100g and 0.11 g / 100g, and both the acid value and the peroxide value meet food-grade requirements.

Description

Technical Field

[0001] The invention relates to the technical field of edible oils and fats, and in particular to a pepper flavored shortening based on enzymatic transesterification and a preparation method thereof. Background Art

[0002] Shortening is a major category of food-grade fats and oils, and its name comes from the word "shorten." In the national standard GB / T 38069-2019 "Shortening," shortening is defined as a fluid, semi-solid, or solid oil product made from edible animal and vegetable fats and oils, as well as one of their hydrogenated, fractionated, or transesterified fats, or a mixture of these fats and oils, with or without quenching and kneading, and with or without the addition of food additives and nutritional enhancers. The raw materials for shortening are primarily derived from animal and vegetable fats and oils. Vegetable fats primarily include soybean oil, palm oil, and rapeseed oil, while animal fats include lard, beef tallow, mutton fat, and their modified oils. In terms of preparation, the main technical approaches for shortening include physical mixing, hydrogenation, fractionation, and transesterification. As a type of edible oil with specific plasticity, shortening properties, cheeseability and oxidative stability, shortening is widely used in the food industry in processing areas such as baked products, fried foods and frozen dough; its core function comes from the supporting role of the oil crystal network on the food matrix.

[0003] Most shortenings on the market are made from vegetable oils and animal fats, and are prepared by physical mixing, hydrogenation or ester exchange.

[0004] Document 1: CN 201410320515 X A shortening for baking

[0005] Document 1 includes the following steps: Step 1: Melting and mixing extremely hydrogenated vegetable oil, lard solid fat, and an emulsifier; Step 2: Cooling the melted mixture obtained in Step 1 in two stages: first, cooling the melted mixture to 40°C over 3-5 minutes, and second, cooling the cooled mixture to 18-22°C over 20-25 minutes; Step 3: Kneading the cooled mixture in Step 2; and Step 4: Curing the kneaded mixture at a constant temperature to obtain the shortening. The shortening prepared using the two-stage cooling method of the present invention is free of sanding and exhibits excellent plasticity and emulsification properties. It also reduces the amount of animal fats such as lard and tallow that could potentially be released into the environment, thereby alleviating the environmental burden.

[0006] Document 2: CN 2012103523308 Shortening composition containing extremely hydrogenated high-erucic acid rapeseed oil

[0007] Document 2 provides a shortening composition comprising extremely hydrogenated high-erucic acid rapeseed oil and a different vegetable oil than the extremely hydrogenated high-erucic acid rapeseed oil. The extremely hydrogenated high-erucic acid rapeseed oil comprises 1-40% by weight of the shortening composition, and the other vegetable oil is selected from rice fat and conventional rapeseed oil. The shortening composition of the present invention can be used as a lard substitute, providing superior frying performance while overcoming the drawbacks of lard, such as low vitamin E content and high cholesterol.

[0008] Document 3: CN 202210915821 2 discloses a Chinese tallow fat-based shortening and a preparation method thereof

[0009] The preparation method comprises the following steps: heating Chinese tallow fat until it is completely melted, then performing ultrasonic degassing treatment, heat preservation treatment, then naturally cooling to room temperature under nitrogen pressure, and then standing treatment to obtain degassed Chinese tallow fat; heating the degassed Chinese tallow fat, then performing ultrasonic treatment, and finally adding 52-degree palm stearin, soybean oil, an enzyme preparation, and an emulsifier, and stirring to obtain emulsified shortening; cooling the obtained emulsified shortening under nitrogen pressure, then treating it in a high-speed vacuum kneader, and evacuating to -0.5 MPa after the treatment to obtain Chinese tallow fat-based shortening. The Chinese tallow fat-based shortening obtained by the present invention has good caseinability and water absorption and excellent processing performance.

[0010] From the above, we can see that Document 1 is a fat obtained by physical mixing, Document 2 is a shortening obtained by hydrogenation, and Document 3 is a shortening obtained by transesterification. However, physical mixing and hydrogenation methods have defects: (1) the mixed fats obtained by physical mixing have poor compatibility; (2) trans-fatty acids (TFAs) produced during the hydrogenation process have been shown to be significantly associated with cardiovascular diseases such as myocardial infarction and arteriosclerosis, insulin resistance, diabetes, and health risks such as colon cancer, prostate cancer, and breast cancer. During the hydrogenation process, some unsaturated fatty acids will be converted into trans fatty acids under metal catalysts, vacuum, and high heat conditions. Therefore, long-term consumption will inevitably have adverse effects on the body.

[0011] Among oil and fat modification technologies, transesterification technology has strong advantages in transforming the physical, chemical and thermal properties of oils and fats. It refers to a type of reaction in which oils or esters composed of fatty acids react chemically with fatty acids, alcohols or other esters, and new esters are produced by the exchange of fatty acid groups. In terms of health effects, lipids after transesterification can improve the digestibility and absorption rate of saturated fatty acids. At present, transesterification technology has been widely used in the preparation of various structural fats such as shortening, margarine, cocoa butter substitutes, low-calorie structural fats and essential fatty acid-rich fats. Among them, enzymatic transesterification has many advantages such as strong specificity, controllable process, mild reaction conditions, high enzyme catalytic activity, faster reaction speed, green and environmental protection, easy separation of product and enzyme, and reusable enzyme.

[0012] With breakthroughs in modern oil and fat engineering technology, functional shortenings based on natural oil compounding have become a research focus. The core of their design lies in mimicking the physical properties of hydrogenated oils, such as plasticity and melting curve, through the synergistic effects of oils with different melting points, while also avoiding the harmful effects of trans fatty acids. In recent years, natural solid oils such as palm stearin and shea butter have been widely used in shortening systems due to their unique physical and chemical properties. Palm stearin is rich in high-melting-point triglycerides such as palmitic-oleic-palmitic triglycerides (POP) and tripalmitin (PPP), which form a stable β' crystal structure at room temperature. This fine and uniform crystal structure creates a dense fat network, providing excellent aeration and facilitating the melting and crystallization of certain fat products. Consequently, it is widely used in various food processing applications. Shea butter, on the other hand, exhibits excellent stability and low-temperature ductility due to its high proportion of symmetrical triglycerides. This ensures that the shortening maintains good processing properties during storage and at low temperatures, for example, allowing for better integration into dough when making puff pastry. Shea butter can adjust the hardness of shortenings to meet product requirements for spreadability. Omitting shea butter can result in an unsuitable hardness in the final product, or lead to unstable crystallization or stratification of shortenings at low temperatures, altering the product's texture. Furthermore, soybean oil, rich in unsaturated fatty acids, can effectively adjust system fluidity and is also a suitable raw material for developing low-TFAs shortenings.

[0013] Shea butter has a multifaceted impact on shortening. Shea butter contains a high amount of unsaturated fatty acids, such as oleic acid, which hydrolyzes to produce free fatty acids. Alternatively, the addition of shea butter to shortening increases its acid value (AV). Furthermore, shea butter's high fatty acid content and complex lipid structure strengthen the intermolecular forces within the fluid, leading to a higher initial viscosity in the shortening after adding shea butter, as measured by rheology.

[0014] The morphological characteristics of fat crystals include the size and morphology of single crystals and aggregates, which are key factors in determining the macroscopic mechanical properties of their three-dimensional network structure, and directly affect the sensory properties of oil products, such as texture, taste and granularity. X-ray diffraction technology can be used to quantitatively analyze the relative content of different crystal forms in oils and fats. There are mainly three characteristic crystal forms in shortening: α, β and β'. From a crystallographic point of view, the β' crystal form is generally considered to be the most ideal crystal form for shortening because of its unique needle-like microstructure and excellent network building ability, which allows it to incorporate more air. In contrast, the α crystal form is easy to transform into the β' and β crystal forms in practical applications due to its loose molecular arrangement and poor thermodynamic stability, so it is often not the main research object. Although the β crystal form has the highest thermodynamic stability, its coarse flaky crystals can easily lead to an undesirable sandy feel in the product. Bragg diffraction analysis shows that the β' crystal form is The characteristic spacing is shown at , while the characteristic spacing corresponding to the β crystal is The relative content of β' and β crystal forms can be calculated by the diffraction peak intensity here.

[0015] The crystal transformation of shea butter is relatively complex and is affected by many factors. It requires appropriate cooling rate, temperature, and the presence of specific crystal seeds. Therefore, its tendency to form β' crystal form is not as strong as palm oil stearin. In contrast, palm oil stearin can form β' crystal form at more temperatures after ester exchange reaction. Relatively speaking, the transformation of shea butter from β crystal form to β' crystal form is more difficult.

[0016] Zanthoxylum bungeanum, a traditional Chinese medicinal and edible plant, has a volatile oil primarily composed of aromatic compounds (benzene derivatives), aliphatic compounds (hydrocarbons, alcohols, aldehydes, ketones, esters), and terpenoids (oxygen-containing derivatives), as well as the characteristic numbing substance hydroxy-α-sanshool, which imparts its unique "numbing" flavor. Zanthoxylum bungeanum oil has greater potential for application in high-temperature baking scenarios due to its non-volatile numbing compounds (such as hydroxy-α-sanshool) and heat-stable antioxidants. However, existing literature has yet to systematically investigate the construction of shortening systems by combining Zanthoxylum bungeanum oil with vegetable oils and fats. Summary of the Invention

[0017] The invention aims to provide a pepper flavor shortening based on enzymatic transesterification and a preparation method thereof.

[0018] To achieve the above object, one embodiment of the present invention provides a pepper flavored shortening based on enzymatic interesterification, the shortening comprising the following components by weight:

[0019] 25-45 parts of palm oil stearin; 25-45 parts of shea butter;

[0020] 15-25 parts soybean oil; 5-15 parts Sichuan pepper oil;

[0021] Lipase, a catalyst for enzymatic transesterification;

[0022] The proportion of pepper oil should not be less than 5%.

[0023] In a preferred embodiment of the present invention, the shortening comprises the following components by weight:

[0024] 35-45 parts of palm oil stearin; 35-45 parts of shea butter;

[0025] 15 to 25 parts soybean oil; 5 to 15 parts Sichuan pepper oil.

[0026] In a preferred embodiment of the present invention, the shortening comprises the following components by weight:

[0027] 45 parts of palm oil stearin; 25 parts of shea butter;

[0028] 25 parts of soybean oil; 5 parts of Sichuan pepper oil.

[0029] In a preferred embodiment of the present invention, the shortening comprises the following components by weight:

[0030] 35 parts of palm oil stearin; 35 parts of shea butter;

[0031] 20 parts of soybean oil; 10 parts of pepper oil.

[0032] In a preferred embodiment of the present invention, the catalyst lipase is an immobilized lipase.

[0033] The present invention also discloses a method for preparing pepper flavored shortening based on enzymatic transesterification, comprising the following steps:

[0034] Step (1) Prepare raw materials

[0035] 25-45 parts of palm oil stearin; 25-45 parts of shea butter;

[0036] 15-25 parts soybean oil; 5-15 parts Sichuan pepper oil;

[0037] Lipase as catalyst for enzymatic transesterification;

[0038] The proportion of Sichuan pepper oil is not less than 5%;

[0039] Step (2) preheating the formulated amounts of palm stearin, shea butter, soybean oil and Sichuan pepper oil at 65° C. to 75° C., adding lipase for rotary evaporation after preheating, controlling the rotation speed to 180 r / min to 220 r / min, and reacting for 3 h to 5 h to complete the transesterification process; then removing the lipase to terminate the reaction.

[0040] In a preferred embodiment of the present invention, the preheating temperature in step (2) is 70°C, the reaction temperature of the transesterification is 70°C, the added lipase is solid lipase particles, the reaction time is 4 hours, and the lipase is removed by centrifugation; after removing the lipase, the obtained product is stored at low temperature.

[0041] In summary, the present invention has the following advantages:

[0042] 1. The present invention uses enzymatic transesterification technology, with palm oil stearin, shea butter, and soybean oil as the base, and innovatively introduces pepper oil to successfully develop a new shortening system with regional flavor. The pepper flavor shortening of the present invention has an acid value between 0.2-0.5 mg / g and a peroxide value between 0.05-0.11 g / 100 g, both meeting food grade requirements. In terms of hardness, the pepper flavor shortening of the present invention has a hardness value of 40g-80g, meeting the requirements of traditional plastic oils and spreadable oil products. In terms of rheological properties, the sample has pseudoplastic fluid characteristics.

[0043] 2, what acid value reflected is the content of free fatty acids in grease, and palm oil stearin is lower or better stability containing free fatty acids, and the palm oil stearin of high proportion can suppress hydrolysis reaction, reduces free fatty acids and generates, and therefore the higher acid value AV of palm oil stearin content is minimum.Shea butter contains more unsaturated fatty acids (as oleic acid), and facile hydrolysis produces free fatty acids, and the free fatty acid content of raw material itself is also higher, so its AV is the highest.The present invention adds Zanthoxylum bungeanum oil, can scavenging free radical and suppress chain reaction by the phenols, terpenoids in Zanthoxylum bungeanum oil, makes the overall peroxide value of shortening lower.

[0044] 3. The initial viscosity of shea butter is higher, while the initial viscosity of palm oil is lower. The present invention adds zanthoxylum bungeanum oil and can significantly improve the overall viscosity of shortening after transesterification, so that shortening can reduce the viscosity of shortening by transesterification of zanthoxylum bungeanum oil when adding a large amount of shea butter. That is, shea butter improves the initial viscosity of shortening system after adding palm oil stearin, and after adding zanthoxylum bungeanum oil for transesterification, the initial viscosity of shortening can be reduced.

[0045] 4. During the processing, the β-crystal form of palm oil stearin is easily transformed into the β' crystal form, while the β-crystal form of shea butter is not easy to transform into the β' crystal form. The present invention increases the content of the β-crystal form of shea butter that transforms into the β' crystal form by adding pepper oil for transesterification, so that the shortening as a whole has better product quality, makes the product crystal structure fine and uniform, can build a dense fat network, not only provides good ventilation capacity, but also is conducive to the melting and crystallization of certain fat products, and the product is fine and has no obvious graininess. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 The following are the apparent viscosity curves of five kinds of Sichuan pepper flavored shortening and commercially available water-free shortening;

[0047] Figure 2 The following are the dynamic frequency sweep curves of storage modulus of five kinds of Sichuan pepper flavor shortening and commercial anhydrous shortening;

[0048] Figure 3 The following are the dynamic frequency sweep curves of loss modulus of five kinds of Sichuan pepper flavor shortening and commercial anhydrous shortening.

[0049] Figure 4 The following are the loss factor curves of five kinds of Sichuan pepper flavor shortening and commercial anhydrous shortening;

[0050] Figure 5 These are the XRD patterns of five kinds of Sichuan pepper flavored shortenings and commercially available anhydrous shortening. DETAILED DESCRIPTION

[0051] The present invention provides a pepper flavored shortening based on enzymatic transesterification, the shortening comprising the following components by weight:

[0052] 25-45 parts of palm oil stearin; 25-45 parts of shea butter;

[0053] 15-25 parts soybean oil; 5-15 parts Sichuan pepper oil;

[0054] Lipase as catalyst for enzymatic transesterification;

[0055] The proportion of pepper oil should not be less than 5%.

[0056] The present invention discloses a pepper flavored shortening based on enzymatic transesterification. The shortening comprises the following components by weight:

[0057] 35-45 parts of palm oil stearin; 35-45 parts of shea butter;

[0058] 15 to 25 parts soybean oil; 5 to 15 parts Sichuan pepper oil.

[0059] The present invention discloses a pepper flavored shortening based on enzymatic transesterification. The shortening comprises the following components by weight:

[0060] 45 parts of palm oil stearin; 25 parts of shea butter;

[0061] 25 parts of soybean oil; 5 parts of Sichuan pepper oil.

[0062] The present invention discloses a pepper flavored shortening based on enzymatic transesterification. The shortening comprises the following components by weight:

[0063] 35 parts of palm oil stearin; 35 parts of shea butter;

[0064] 20 parts of soybean oil; 10 parts of pepper oil.

[0065] The catalyst lipase of the present invention may be an immobilized lipase.

[0066] The present invention also discloses a method for preparing pepper flavored shortening based on enzymatic transesterification, comprising the following steps:

[0067] Step (1) Prepare raw materials

[0068] 25-45 parts of palm oil stearin; 25-45 parts of shea butter;

[0069] 15-25 parts soybean oil; 5-15 parts Sichuan pepper oil;

[0070] Lipase, a catalyst for enzymatic transesterification;

[0071] Step (2) preheating the formulated amounts of palm stearin, shea butter, soybean oil and Sichuan pepper oil at 65° C. to 75° C., adding lipase for rotary evaporation after preheating, controlling the rotation speed to 180 r / min to 220 r / min, and reacting for 3 h to 5 h to complete the transesterification process; then removing the lipase to terminate the reaction.

[0072] In step (2), the preheating temperature is 70° C., the reaction temperature of the transesterification is 70° C., the added lipase is solid lipase particles, the reaction time is 4 h, and the lipase is removed by centrifugation; after removing the lipase, the obtained product is stored at low temperature.

[0073] Preparation method 1: The method for preparing shortening by enzymatic interesterification is as follows:

[0074] Step (1) Prepare raw materials

[0075] Step (2) preheating the palm oil stearin, shea butter, soybean oil and pepper oil in the formulated amounts at 70° C., adding solidified lipase particles after preheating and treating them using a rotary evaporator, controlling the speed to 200 r / min, and reacting at 70° C. for 4 h to complete the transesterification process; then removing the solidified lipase by centrifugation to terminate the reaction, and storing the mixture at 4° C. after the reaction is completed.

[0076] Example 1: A shortening formula of the present invention

[0077] 35 parts of palm oil stearin; 35 parts of shea butter;

[0078] 25 parts of soybean oil; 5 parts of Sichuan pepper oil.

[0079] Example 2: A shortening formula of the present invention

[0080] 45 parts of palm oil stearin; 25 parts of shea butter;

[0081] 25 parts of soybean oil; 5 parts of Sichuan pepper oil.

[0082] Example 3: A shortening formula of the present invention

[0083] 25 parts of palm oil stearin; 45 parts of shea butter;

[0084] 25 parts of soybean oil; 5 parts of Sichuan pepper oil.

[0085] Example 4: A shortening formula of the present invention

[0086] 35 parts of palm oil stearin; 35 parts of shea butter;

[0087] 20 parts of soybean oil; 10 parts of pepper oil.

[0088] Example 5: A shortening formula of the present invention

[0089] 35 parts of palm oil stearin; 35 parts of shea butter;

[0090] 15 parts of soybean oil; 15 parts of pepper oil.

[0091] The shortenings in Examples 1 to 5 can all be prepared by the enzymatic transesterification method disclosed in Preparation Method 1.

[0092] Commercially available shortening was purchased from COFCO Donghai Cereals and Oils Industry Co., Ltd.

[0093] Experimental Example 1: Physical and Chemical Properties of Shortening of the Present Invention

[0094] Detection method: The physical and chemical properties of the oil after the transesterification reaction are measured. The acid value (AV) of the oil is determined by the titration method in accordance with the national standard GB 5009.227-2023 "National Food Safety Standard - Determination of Acid Value in Foods". The peroxide value (POV) of the oil is determined by the cold solvent indicator titration method in accordance with the national standard GB5009.229-2016 "National Food Safety Standard - Determination of Peroxide Value in Foods".

[0095] The test results are as follows:

[0096] Group AV (mgKOH / g) POV(g / 100g) Example 1 <![CDATA[0.3567±0.0044 c ]]> <![CDATA[0.0859±0.0042 c ]]> Example 2 <![CDATA[0.2798±0.0083 a ]]> <![CDATA[0.0525±0.0037 a ]]> Example 3 <![CDATA[0.4391±0.0110 d ]]> <![CDATA[0.1027±0.0042 d ]]> Example 4 <![CDATA[0.3157±0.0118 b ]]> <![CDATA[0.0739±0.0036 c ]]> Example 5 <![CDATA[0.3087±0.0061 b ]]> <![CDATA[0.0657±0.0037 b ]]> Commercially available <![CDATA[0.7162±0.0235 e ]]> <![CDATA[0.1135±0.0178 d ]]>

[0097] What acid value reflected is the content of free fatty acids in grease, can be drawn by upper table, and in embodiment 2, acid value AV is minimum, is 0.2798, is because palm oil stearin contains free fatty acids lower or better stability; And the saturated fatty acids (palm oil stearin is main) of high ratio can suppress hydrolysis reaction, reduces free fatty acids and generates, so its AV is minimum. Containing shea butter ratio is the highest in embodiment 3, the acid value AV of sample is the highest, is 0.4391, is because shea butter contains more unsaturated fatty acids (such as oleic acid), and facile hydrolysis produces free fatty acids, and raw material itself free fatty acid content is also higher, so its AV is the highest.

[0098] Peroxide value (POV) reflects the content of initial oxidation products in oils and fats and is correlated with antioxidant capacity and fatty acid unsaturation. The POV value of the sample in Example 5, containing 15% Sichuan pepper oil (0.0657), was significantly lower than that of the sample in Example 1 (0.0859), indicating that the phenolic and terpenoid compounds in Sichuan pepper oil inhibit the oxidative chain reaction by scavenging free radicals. Furthermore, compared to the sample in Example 4 containing 20% ​​soybean oil, the sample in Example 5 containing 15% soybean oil contained less polyunsaturated fatty acids (linoleic acid), thereby reducing oxidative substrates and further lowering POV.

[0099] Experimental Example 2: Hardness Test of Shortening of the Present Invention

[0100] Testing method: With reference to the method of Palla et al. and with slight modifications, a P / 6 cylindrical probe was used to measure the texture of oils before and after the transesterification reaction. The experimental parameters were as follows: the probe movement speeds before, during, and after the test were 5 mm / s, 1 mm / s, and 5 mm / s, respectively; the probe depression depth was 20 mm; and the data were processed using Texture Exponent Lite 32 (Vs. 4.9.8.0) software.

[0101] Group hardness elasticity Example 1 <![CDATA[58.51±3.10 c ]]> <![CDATA[686.83±40.70 c ]]> Example 2 <![CDATA[73.84±1.21 b ]]> <![CDATA[761.53±29.80 b ]]> Example 3 <![CDATA[44.83±1.83 d ]]> <![CDATA[513.24±6.71 d ]]> Example 4 <![CDATA[55.38±2.48 c ]]> <![CDATA[664.00±43.55 c ]]> Example 5 <![CDATA[58.35±2.94 c ]]> <![CDATA[653.91±38.40 c ]]> Commercially available <![CDATA[113.52±5.25 a ]]> <![CDATA[833.74±20.54 a ]]>

[0102] As can be seen from the table above, the hardness values ​​of the five Sichuan pepper flavor shortenings range from 40 to 80g. Haighton's hardness measurements of traditional plastic oils indicate that their yield values ​​are generally between 50 and 1000g / cm 2 The hardness of the five transesterified oils prepared by the present invention meets the requirements of traditional plastic oils. If the transesterified oils are used as base oils for spreadable oil products, their hardness can also meet the product's requirements for spreadability.

[0103] Under the same transesterified oil substrate, as the proportion of soybean oil gradually increases, the hardness of the oil gradually decreases after transesterification. This is because the fatty acid composition of the oil changes due to oil modification. Generally, the more saturated fatty acids in the oil, the greater its hardness value. This is because saturated triglycerides with a high melting point can form a three-dimensional network with better mechanical properties in the oil.

[0104] Experimental Example 3: Rheological Properties - Viscosity Test

[0105] Viscosity testing was performed using a rheometer in controlled rate mode with a shear rate of 0.1s-1 to 100s-1, a shear duration of 300s, and a linear sampling method. The apparent viscosity data were fitted using the Power Law model to describe fluidity.

[0106] The rheological viscosity test of Examples 1 to 5 of the present invention and commercially available shortening was performed, and the test results were as follows: Figure 1 As shown. Figure 1 As shown in Figure 2, all curves show that along with the increase of shear rate, viscosity is on a downward trend, which indicates that these samples all have the characteristic of pseudoplastic fluid. When the shear force subjected to increases, the molecular structure inside the fluid is destroyed, and the entanglement between molecules is reduced, making the fluid easier to flow, thereby causing viscosity reduction. Under the initial state, the viscosity of Example 3 containing 45% shea butter is obviously higher than other samples, because shea butter contains more saturated fatty acids and complex lipid structure, making the intermolecular force inside the fluid stronger, thereby initial viscosity is higher. In Example 2, the content of shea butter is the lowest, and its initial viscosity is also the lowest. The content of shea butter in all other embodiments is similar, and its initial viscosity is close; thus, the content of shea butter is positively correlated with the initial viscosity, and the higher the content of shea butter, the higher the initial viscosity of its shortening. And from Example 1, Example 4 and Example 5, the initial viscosities of the three embodiments are 7755 mPa.s, 7958 mPa.s and 7853 mPa.s, respectively. The difference between the three is very small. The proportions of palm oil stearin and shea butter in the above three embodiments are the same, indicating that soybean oil has little effect on the initial viscosity.

[0107] Experimental Example 3 Control Group:

[0108]

[0109]

[0110] The control group in Experimental Example 3 was prepared by enzymatic transesterification to obtain the corresponding shortening, and then all shortenings were subjected to viscosity testing to obtain the initial viscosity of the control group. The test results are shown below:

[0111] Group Initial viscosity mPa.s Group Initial viscosity mPa.s Control group 3B 6345 Control group 31 11480 Control group 3C 11642 Control group 32 12106 Example 2 5389 Control group 33 10984 Example 3 9997 Control group 34 11782

[0112] The initial viscosity data of Example 2 and Example 3 are the same as Figure 1 The data when the middle shear rate is 0 are consistent.From the above-mentioned testing result, can be seen that control group 3B is compared with embodiment 2, and control group 3C is compared with embodiment 3, from the comparison result, the initial viscosity data of control group 3B and control group 3C are all greater than the embodiment that added Zanthoxylum bungeanum under equal circumstances, then illustrate after adding Zanthoxylum bungeanum, after enzymatic transesterification, add Zanthoxylum bungeanum can reduce the side effect that shea butter improves initial viscosity under same proportioning situation, illustrate that Zanthoxylum bungeanum can produce certain regulating effect to the rheological property of system after carrying out transesterification with palm oil and shea butter, make the initial viscosity of system lower.Similarly, when adopting mechanical method to carry out relevant treatment, be about to the shortening obtained after various raw materials through mixing, kneading and cooling treatment.When the shortening in control group 3B and embodiment 2 was used mechanical method to prepare, the reduction of its initial viscosity was not significant without transesterification, even if illustrate and add Zanthoxylum bungeanum to reduce initial viscosity, also be that preparation method is had selectivity.

[0113] Experimental Example 4: Rheological Properties - Dynamic Frequency Sweep

[0114] Dynamic frequency sweep method: sweep frequency 0.1Hz-50Hz, control temperature 25℃, logarithmically select points, and measure the changes in elastic modulus (G′) and viscous modulus (G″) of oil and fat with frequency change.

[0115] Storage modulus (G') and loss modulus (G"), the storage modulus represents the elastic response of the material, and the loss modulus represents the viscoelastic response of the material. By analyzing the frequency sweep data, the solid and liquid behaviors of the material can be determined. The test results of Experimental Example 4 are as follows Figure 2 and Figure 3 shown.

[0116] Figure 2 As can be seen from the results, the G' of all samples decreases as angular frequency increases, indicating that the elastic response of material decreases as angular frequency increases. At low angular frequencies, the G' of embodiment 2 is the highest, because its palm oil stearin content is the highest, and its crystalline structure and higher saturation make the system have stronger elasticity when low frequency. And the high shea butter content contained in embodiment 3, because of its special lipid structure, helps to form stronger intermolecular interaction, thereby enhancing the elasticity of the system, also making its G' higher.

[0117] Figure 3As shown, the variation trend of G" of different samples with angular frequency is relatively complex. In general, some samples first decrease and then increase. The G" of sample C has an obvious upward trend at high angular frequency and a high value, which may be due to the intermolecular friction and energy loss of the components in shea butter under high-frequency disturbance. The G" of Example 2 is relatively low in the range of low to medium angular frequencies, indicating that its internal structure has relatively little energy loss in this frequency range, which may be related to the structural characteristics of palm oil stearin.

[0118] The loss factor Tanδ=G” / G’ reflects the relative size of the viscosity and elasticity of the material. Figure 4 As shown, the Tanδ values ​​of all samples increase with increasing angular frequency, indicating that the material's viscous response strengthens with increasing angular frequency. Sample C exhibits a larger increase in Tanδ and a higher final value, indicating that the viscous characteristics of Example 3 are more pronounced at high angular frequencies. This aligns with the analysis of G" above, which indicates that the shea butter component leads to large energy loss and increased viscosity at high frequencies. The consistently low Tanδ values ​​of Example 2 indicate that elasticity is relatively dominant at different angular frequencies, which is attributed to the superior elastic structure imparted by palm oil stearin to the system.

[0119] Experimental Example 5: Crystal Form Detection

[0120] Testing method: An X-ray crystal diffractometer was used to determine the crystal form of the oil sample. Before testing, the oil sample was completely melted at 70°C for 30 minutes, then stored at 20°C for 12 hours. An appropriate amount of the oil sample was then evenly applied to the test piece. The XRD test parameters were set as follows: voltage 40kV, current 30mA; 2θ scanning range 10-80°, scanning rate 2° / min. The relative contents of β and β' crystals were calculated according to the following formula:

[0121]

[0122] According to the interplanar spacing d When β-type is used, d is and When , the calculation is performed for the β' crystal form. I represents the peak intensity at the corresponding interplanar spacing. The characteristic spacing is shown at , while the characteristic spacing corresponding to the β crystal is The relative content of β' and β crystal forms can be calculated by the diffraction peak intensity here. Figure 5 As shown, according to Figure 5 Calculations were performed to obtain the crystal content data for Examples 1 to 5 and commercially available products.

[0123] Sample name β-type crystal content (%) β'-type crystal content (%) Example 1 38.46％ 61.54％ Example 2 36.19％ 63.81％ Example 3 39.10％ 60.90％ Example 4 38.83％ 61.17％ Example 5 38.95％ 61.05％ Commercially available 44.77％ 55.23％

[0124] As can be seen from the above table, the β ' crystal form content of embodiment 2 is the highest, because palm stearin is rich in the high melting point triglycerides such as palmitic acid-oleic acid-palmitic acid triglyceride POP, tripalmitin PPP, more easily forms stable β ' crystal formation at normal temperatures.And the β ' crystal form content of embodiment 3 is minimum, because its shea butter content is high, and the crystal formation transformation of shea butter is comparatively complicated, is affected by multiple factors, needs suitable cooling rate, temperature and has the conditions such as specific crystal seed, therefore its tendency to form β ' crystal formation is not as strong as palm oil stearin.The palm oil stearin of all the other embodiment 1, embodiment 4 and embodiment 5 is identical with the proportioning of shea butter, so β ​​' crystal form content is little different.

[0125] Experimental Example 5 Control Group

[0126]

[0127] The control group in Experimental Example 5 was subjected to an enzymatic transesterification method to prepare the corresponding shortening, and then all shortenings were tested for the content of β' crystal form. The test results are shown below:

[0128]

[0129]

[0130] From the above comparison of β' crystal content, it can be seen that control group 5B corresponds to the ratio of Example 2, and control group 5C corresponds to the raw material ratio of Example 3. Compared with the control group, Examples 2 and 3 added Sichuan pepper oil as a raw material for transesterification. The β' crystal content of the shortening obtained after transesterification increased to a certain extent. However, after replacing Sichuan pepper oil with other conventional edible oils, the β' crystal content failed to achieve the same technical effect as Sichuan pepper oil. In some control groups 53, the β' crystal content was even reduced. This indicates that the effect of transesterification between different oils on the β' crystal content is a combined result of the oil's own structure and the interaction with other oils during transesterification.

[0131] From the comparison of control group 56 to control group 58, it can be seen that the addition of pepper oil has no significant effect on the β' crystal content of palm oil stearin, but the addition of pepper oil has a significant effect on the crystal content of shea butter after ester exchange, that is, pepper oil can promote the conversion of shea butter to more β' crystal.

[0132] Experimental Example 6: Sensory Experiment

[0133] 20 people were randomly invited to form a sensory tasting panel, including 10 boys and 10 girls. They were asked to comprehensively score the four indicators of color, tissue state, smell and appearance of each experimental group according to the prescribed scoring criteria, and the average value was taken as the final result. The scoring criteria are shown below.

[0134]

[0135] The comprehensive scores of each embodiment of the sensory test of the present invention are as follows:

[0136] Sample name Comprehensive score Example 1 90.5 Example 2 88 Example 3 92 Example 4 82 Example 5 81

[0137] Overall, Example 3 showed a relatively balanced performance across all indicators. Its low Sichuan pepper oil content provided advantages in color and aroma, while its moderate soybean oil content resulted in a better texture. Its appearance also presented no significant detrimental factors, resulting in the highest overall sensory score. Overall, the changes in the proportions of the various oil components combinedly impacted the product's color, aroma, appearance, and texture, leading to differences in sensory scores.

[0138] Although the specific embodiments of the present invention are described in detail in conjunction with the accompanying drawings, this should not be construed as limiting the scope of protection of this patent. Within the scope described by the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A pepper flavored shortening based on enzymatic interesterification, characterized in that: The shortening comprises the following components by weight: 25-45 parts of palm oil stearin; 25-45 parts of shea butter; 15-25 parts soybean oil; 5-15 parts Sichuan pepper oil; Lipase, a catalyst for enzymatic transesterification; The proportion of pepper oil should not be less than 5%.

2. The prickly ash flavored shortening based on enzymatic interesterification according to claim 1, wherein: The shortening comprises the following components by weight: 35-45 parts of palm oil stearin; 35-45 parts of shea butter; 15-25 parts soybean oil; 5-15 parts Sichuan pepper oil.

3. The pepper flavor shortening based on enzymatic interesterification according to claim 1, wherein: The shortening comprises the following components by weight: 45 parts of palm oil stearin; 25 parts of shea butter; 25 parts of soybean oil; 5 parts of Sichuan pepper oil.

4. The pepper flavor shortening based on enzymatic interesterification according to claim 1, wherein: The shortening comprises the following components by weight: 35 parts of palm oil stearin; 35 parts of shea butter; 20 parts of soybean oil; 10 parts of pepper oil.

5. The pepper flavor shortening based on enzymatic interesterification according to claim 1, wherein: The catalyst lipase is solidified lipase.

6. A method for preparing pepper flavored shortening based on enzymatic interesterification, comprising the following steps: Step (1) Prepare raw materials 25-45 parts of palm oil stearin; 25-45 parts of shea butter; 15-25 parts soybean oil; 5-15 parts Sichuan pepper oil; Lipase, a catalyst for enzymatic transesterification; The proportion of Sichuan pepper oil should not be less than 5%; Step (2) preheating the palm oil stearin, shea butter, soybean oil and Sichuan pepper oil in the formula at 65° C. to 75° C., adding lipase and rotary evaporation after preheating, controlling the speed at 180 r / min to 220 r / min, and reacting for 3 h to 5 h to complete the transesterification process; The reaction is then terminated by removing the lipase.

7. The preparation method according to claim 6, wherein: In the step (2), the preheating temperature is 70° C., the reaction temperature of the transesterification is 70° C., the added lipase is solid lipase particles, the reaction time is 4 hours, and the lipase is removed by centrifugation; after removing the lipase, the obtained product is stored at low temperature.

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