The invention relates to a method for regulating beta apos; crystal-form low-saturated fatty acid powdered oil as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of powdered oil and fat and processing, and particularly relates to a preparation method of low saturated fatty acid powdered oil and fat capable of regulating and controlling beta'crystal form, which comprises the following steps: S1, mixing oil and fat with palm stearin, dehydrating and cooling; then, immobilized lipase is added for reaction, and low-saturated fatty acid ester exchange grease is obtained; s2, mixing the obtained low saturated fatty acid ester exchange grease with a gelator to prepare an oil phase; s3, dissolving a wall material and an emulsifier in water to form a water phase; and S4, mixing the oil phase and the water phase in proportion to form an emulsion, and drying to obtain the low saturated fatty acid powdered oil. Compared with the prior art, by integrating enzymatic transesterification and oleogel technologies, physical and chemical grease structuring technologies are fused, on the basis of ensuring zero trans-fatty acid, baking performance is optimized through accurate crystal form regulation and control, the industry blank of zero trans-fatty acid-high beta'crystal form 'is filled up, and the method is suitable for industrial production. The method has a good application prospect in the field of healthy baked food development and processing.

Description

Technical Field

[0001] The present invention belongs to the technical field of powder fats and processing, and particularly relates to a low-saturated-fatty-acid powder fat for regulating β'-crystal form, a preparation method thereof, and an application thereof. Background Art

[0002] The sensory quality and shelf life of baked goods highly depend on the functional properties of fats and oils. By lubricating the gluten network, stabilizing the bubble structure, and delaying starch retrogradation, etc., they endow the products with a unique soft texture and uniform pore structure. Although traditional baking fats and oils (such as butter and shortening) can effectively achieve the above functions, their high saturated fatty acid content (up to 60-70% in natural butter), inconvenient transportation and storage due to solid state characteristics, and problems such as processing temperature sensitivity are difficult to meet the requirements of the modern food industry for health and efficient production. As an innovative form of solid fats and oils, powder fats and oils encapsulate liquid fats and oils in a wall material matrix through microencapsulation technology, with good fluidity, high oxidation stability, and potential for nutritional fortification, becoming an ideal solution to replace traditional fats and oils. However, due to limitations in the technical route, commercially available powder fats and oils still face the industry pain point of difficulty in synergistically optimizing health attributes and functional performance.

[0003] Commercially available powder fats and oils mainly use hydrogenated oils or pure vegetable oils as the base materials: Although the hydrogenation process can improve the processing performance of fats and oils, it is accompanied by residual trans fatty acids (the detection value of some non-dairy creamers reaches 0.5 g / 100 g) and an increase in the proportion of saturated fatty acids, which is contrary to the global regulations on trans fatty acid restrictions and the low-fat and healthy trend; Although the pure vegetable oil base material avoids the hydrogenation risk, it has functional defects due to insufficient crystal form regulation - the high-temperature processing of traditional microencapsulation processes (such as spray drying) easily destroys the crystal structure of fats and oils, resulting in a significant reduction in the proportion of β'-crystal form. As the ideal form of baking fats and oils, its fine crystals can be evenly dispersed in the dough, significantly improving the bread specific volume and anti-aging property by stabilizing the air chamber interface.

[0004] In addition, the following bottlenecks also exist in the prior art:

[0005] There is a contradiction between process complexity and stability. The traditional preparation process requires the coordination of multiple steps, with high energy consumption and a microencapsulation efficiency of only 60-80%. At the same time, it relies on a large amount of wall materials (such as maltodextrin) to maintain oxidation stability, which is prone to surface oil seepage; There are limitations in oil phase modification technologies. The hydrogenation process relies on metal catalysts (such as nickel) and generates trans fatty acids; The fractionation method only adjusts the melting point of fats and oils and cannot improve the crystal form or health attributes; Chemical interesterification introduces the risk of sodium / potassium methoxide residues; Although enzymatic interesterification avoids the generation of trans fatty acids, a single process is difficult to precisely regulate the crystal form; Oil gel technologies (such as ethyl cellulose / rice bran wax systems) can achieve zero trans fatty acids, but existing solutions are mostly limited to partial replacement of traditional fats and oils (replacement rate < 30%), and the gel network is prone to softening at high temperatures (SFC < 15%), resulting in oil seepage and texture deterioration.

[0006] The current technology has not yet broken through the synergistic optimization barrier of "zero trans fatty acids - high proportion of β' crystal form - low additives". For example, Patent CN113647627A improves the embedding rate through a composite wall material, but does not involve crystal form regulation; although the high oil-loading powder oil (such as Patent CN43389126A) has an oil loading of 87.25%, it relies on a complex emulsification system (sodium alginate - pectin) and is difficult to adapt to the baking scenario. Therefore, there is an urgent need for an innovative solution for oil structuring to achieve a balance between functional performance and processing efficiency while eliminating health risks. Summary of the Invention

[0007] By integrating enzymatic interesterification and oleogel technology, compared with the prior art, the present invention combines physical and chemical oil structuring technologies to further structure the oil and regulate its processing characteristics. Through chemical regulation, the content of saturated fatty acids in the oil phase is reduced to meet the health requirements of the oil. Physical structuring further regulates the processing characteristics of the oil in baked goods, increases the content of β' crystal form, increases the bread volume, changes the bread texture, and slows down bread staling. This product can completely replace butter in baking applications and improve the texture stability of bread.

[0008] In order to achieve the above invention object, the present invention provides the following technical solutions:

[0009] A preparation method of low-saturated-fatty-acid powder oil for regulating β' crystal form, comprising the following steps:

[0010] S1. Mix the oil with palm stearin, dehydrate and cool; then add immobilized lipase and react to obtain low-saturated-fatty-acid interesterified oil;

[0011] S2. Mix the obtained low-saturated-fatty-acid interesterified oil with a gelling factor to prepare an oil phase;

[0012] S3. Dissolve the wall material and emulsifier in water to form an aqueous phase;

[0013] S4. Mix the oil phase with the aqueous phase, form an emulsion and then dry to obtain the low-saturated-fatty-acid powder oil.

[0014] Preferably, the dehydration and cooling treatment is: vacuum dehydration at 65°C for 1 hour, and cooling to 45°C - 65°C.

[0015] Preferably, the treatment of adding immobilized lipase and reacting is: vacuum reaction at 70 r / min for 2 - 6 hours.

[0016] Preferably, the mixing operation of the oil phase in step S2 is: stirring and dissolving at 80°C - 90°C and then curing at 4°C for 24 hours.

[0017] Preferably, the mixing temperature of the aqueous phase in step S3 is 50°C to 80°C.

[0018] Preferably, the oil is one or more of sunflower oil, soybean oil, rice bran oil, corn oil, fish oil, olive oil, glycerol, grape seed oil, and peanut oil.

[0019] Preferably, the immobilized lipase is sn-1,3 specific immobilized lipase. Calculated based on the substrate, the addition amount of the immobilized lipase is 5% to 8%.

[0020] Preferably, the saturation degree of the low-saturated fatty acid transesterified oil is below 40%.

[0021] Preferably, the gelling factor is one or more of beeswax, rice bran wax, ceramide, sitosterol, oryzanol, palmitic acid, and ethyl cellulose.

[0022] Preferably, the concentration of the gelling factor in the oil phase is 0.1% to 10%.

[0023] Preferably, the wall material is one or more of maltodextrin, modified starch, gum arabic, soy protein isolate, and whey protein; the emulsifier is one or more of sucrose fatty acid ester, soy lecithin, sunflower lecithin, whey protein, and sodium starch octenyl succinate.

[0024] Preferably, the weight ratio of the core material to the wall material is 1:1 to 1:10; the content of the oil phase in the emulsion is 10% to 30%.

[0025] The present invention also provides the application of the powder oil in food processing.

[0026] Furthermore, it is applied to replace butter in bread processing; preferably, the addition amount of the powder oil in bread processing is 5% to 20%.

[0027] More specifically, the present invention also provides a bread processing method, wherein the bread is made from the following percentage of raw materials: a certain amount of flour, and the rest is a mixture of 10 - 30 wt% carbohydrates, 5 - 20 wt% milk powder, 1 - 5 wt% yeast, 3 - 6 wt% powder oil, and 2 - 8 wt% salt based on the flour and 50 - 60 wt% water;

[0028] The bread processing treatment is as follows:

[0029] 1) Pour each raw material into a dough mixer and stir at a low speed (100 - 150 rpm) for 2 minutes until uniform; switch to medium speed (200 - 250 rpm) and stir for 8 - 10 minutes to form a smooth dough (the gluten expansion stage, a stretchable film can be seen); primary fermentation: place the dough in an environment of 28 - 30°C and humidity of 75% - 80% and ferment for 60 - 90 minutes, and the volume expands to 2 - 2.5 times;

[0030] 2) Divide the fermented dough into portions of 150 - 200 g each. After rounding, let it rest and relax for 10 minutes. Roll out the dough to exhaust air, then roll it into a cylindrical shape or form it using a mold, and spray water mist on the surface to prevent cracking.

[0031] 3) Place the formed dough in an environment with a temperature of 35 - 38 °C and a humidity of 80% - 85% for fermentation for 40 - 50 minutes until the volume increases to 1.8 - 2 times. Take out the dough for baking, bake it at 180 °C on the upper fire and 150 °C on the lower fire for 25 minutes. After taking it out of the oven, cool it in a ventilated environment at 25 °C until the central temperature ≤ 30 °C, and store it at room temperature.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0033] Based on the oil microcapsule technology, through the physicochemical structuring modification of the oil phase, the present invention synergistically breaks through health attributes. By replacing the hydrogenation process with transesterification, it completely eliminates trans fatty acids (not detected by GC - MS), avoiding the risk of cardiovascular diseases. Through the physicochemical structured oil, it further reduces saturated fatty acids to adapt to the trend of low - fat healthy foods.

[0034] By directionally regulating the β' crystal form of the oil through the crystal network, it induces the formation of a high proportion of β' crystal form, and its fine crystals are evenly dispersed in the dough, significantly improving the specific volume and anti - aging property of the bread, and improving the texture and shelf life of the product.

[0035] The powdered oil prepared by the present invention meets the food - grade standard and has been successfully applied to bread. It can directly replace butter without adjusting the baking formula, is suitable for bread, cake premixes and frozen dough, simplifying the processing process; it has the potential for nutritional fortification, and the microcapsule wall material can carry functional components such as vitamin E and phytosterols, expanding the dimension of the development of healthy foods. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a solid fat content diagram of the structured oil;

[0037] Figure 2 It is a macroscopic diagram of the powdered oil;

[0038] Figure 3 It is a physicochemical property diagram of the powdered oil;

[0039] Figure 4 It is an XRD diagram of the powdered oil;

[0040] Figure 5 It is a macroscopic quality diagram of the bread;

[0041] Figure 6 It is a specific volume diagram of the bread. DETAILED DESCRIPTION OF THE INVENTION

[0042] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments and comparative examples of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work belong to the scope of protection of the present invention.

[0043] Unless otherwise specified, the test methods used in the following examples are all conventional methods; the materials, reagents, etc. used, unless otherwise specified, are reagents and materials that can be obtained from commercial channels. The immobilized lipase is all sn-1,3 specific immobilized lipase.

[0044] Example 1

[0045] Preparation of a powdery oil:

[0046] (1) Mix soybean oil and palm stearin in a ratio of 30% saturation, dehydrate under vacuum at 65°C for 1 hour, and cool to 45°C - 65°C;

[0047] (2) Add sn-1,3 specific immobilized lipase with a content of 5% of the substance obtained in step (1), and react under vacuum at 70 r / min for 3 hours to obtain low-saturated fatty acid transesterified oil;

[0048] (3) Mix 10 g of the obtained low-saturated fatty acid transesterified oil with 0.7 g of glycerol monostearate, stir and dissolve at 90°C, and then solidify at 4°C for 24 hours to obtain an oil phase;

[0049] (4) Use maltodextrin and whey protein (mixed mass ratio 1:1) as wall materials, add 1% of sucrose fatty acid ester as an emulsifier and dissolve it in water, and stir at 80°C to form an aqueous phase;

[0050] (5) Mix the oil phase and the aqueous phase in a ratio of 2:1 (mass ratio) of wall-core ratio, and form an emulsion through high-speed shearing at 10,000 r / min and high-pressure homogenization at 500 Mpa for 3 times; the solid content (the content of wall materials and core materials in the emulsion) is 15%;

[0051] (6) After the emulsion is ripened, spray-dry at 170°C to obtain the finished powdery oil product.

[0052] (7) Put 500 g of the mixed powder, 60 g of the above powdery oil, 25 g of conventional yeast, 75 g of sugar, 10 g of salt and an appropriate amount of water into a dough mixer and mix;

[0053] (8) Stir the dough mixer at low speed for 2 minutes until uniform; switch to medium speed and stir for 8 - 10 minutes to form a smooth dough (at the gluten expansion stage, a visible film can be stretched); place the dough in an environment of 28 - 30°C and humidity of 75% - 80% and ferment for 60 - 90 minutes, and the volume expands to 2 - 2.5 times.

[0054] (9) Divide the fermented dough into portions of 150 g each, round them up and let them rest for 10 minutes; roll out the dough to exhaust air, roll it into a cylinder or shape it using a mold, and spray water mist on the surface to prevent cracking.

[0055] (10) Place the shaped dough in an environment at 35 - 38 °C and a humidity of 80% - 85% and ferment for 40 - 50 minutes until the volume increases to 1.8 - 2 times; take out the dough for baking, bake at 180 °C on the upper fire / 150 °C on the lower fire for 25 minutes, and after taking out of the oven, cool it in a ventilated environment at 25 °C until the center temperature ≤ 30 °C, and store it at room temperature.

[0056] Example 2

[0057] Preparation of a powder oil:

[0058] (1) Mix soybean oil and palm stearin in a ratio of 30% saturation, dehydrate under vacuum at 65 °C for 1 hour, and cool to 45 °C - 65 °C;

[0059] (2) Add 5% of sn-1,3 specific immobilized lipase and react under vacuum at 70 r / min for 3 hours to obtain a low-saturated fatty acid transesterified oil;

[0060] (3) Mix 10 g of the obtained oil with 0.7 g of candelilla wax, stir and dissolve at 90 °C and then solidify at 4 °C for 24 hours to obtain an oil phase;

[0061] (4) Use maltodextrin and whey protein (1:1) as wall materials, add 1% of sucrose fatty acid ester as an emulsifier and dissolve it in water, and stir at 80 °C to form an aqueous phase;

[0062] (5) Mix the oil phase and the aqueous phase in a ratio of 2:1 by the wall-core ratio, and form an emulsion through high-speed shearing at 10000 r / min and high-pressure homogenization at 500 Mpa for 3 times, with the soluble solid content being 10%;

[0063] (6) After the emulsion is ripened, spray-dry it at 170 °C to obtain the finished powder oil product.

[0064] (7) Put 500 g of the mixed powder, 60 g of the powder oil, 25 g of yeast, 75 g of sugar, 10 g of salt and an appropriate amount of water into a dough mixer and mix;

[0065] (8) Stir at low speed in the dough mixer for 2 minutes until uniform; switch to medium speed and stir for 8 - 10 minutes to form a smooth dough (at the gluten expansion stage, a visible film can be stretched); place the dough in an environment at 28 - 30 °C and a humidity of 75% - 80% and ferment for 60 - 90 minutes until the volume expands to 2 - 2.5 times.

[0066] (9) Divide the fermented dough into portions of 150 g each, round them up and let them rest for 10 minutes; roll out the dough to exhaust air, roll it into a cylinder or shape it using a mold, and spray water mist on the surface to prevent cracking.

[0067] (10) The formed dough is fermented in an environment of 35 - 38°C and humidity of 80% - 85% for 40 - 50 minutes, and the volume increases to 1.8 - 2 times; take out the dough for baking, bake at 180°C on the upper fire / 150°C on the lower fire for 25 minutes, cool it in a ventilated environment at 25°C until the center temperature ≤ 30°C, and store it at room temperature.

[0068] Example 3

[0069] Preparation of a powder oil and fat:

[0070] (1) Mix soybean oil and palm stearin in a ratio of 30% saturation, dehydrate under vacuum at 65°C for 1 hour, and cool to 45°C - 65°C;

[0071] (2) Add 5% of sn-1,3 specific immobilized lipase, react under vacuum at 70 r / min for 3 hours to obtain low-saturated fatty acid transesterified oil and fat;

[0072] (3) Mix 10 g of the obtained oil and fat with 0.7 g of sitosterol and glycerol monostearate, stir and dissolve at 90°C and then solidify at 4°C for 24 hours to form an oil phase;

[0073] (4) Use maltodextrin and whey protein as wall materials, add 1% of sucrose fatty acid ester as an emulsifier and dissolve it in water, stir at 80°C to form an aqueous phase;

[0074] (5) Mix the oil phase and the aqueous phase in a ratio of 2:1 by the wall-core ratio, form an emulsion through high-speed shearing at 10000 r / min and high-pressure homogenization at 500 Mpa for 3 times, and the solid content is 15%;

[0075] (6) After the emulsion is ripened, spray-dry it at 170°C to obtain the finished powder oil and fat product.

[0076] (7) Put 500 g of the mixed powder, 60 g of the powder oil and fat, 25 g of yeast, 75 g of sugar, 10 g of salt and an appropriate amount of water into a dough mixer and mix;

[0077] (8) Stir the dough mixer at low speed for 2 minutes until uniform; switch to medium speed and stir for 8 - 10 minutes to form a smooth dough (the gluten expansion stage, a visible film can be stretched); place the dough in an environment of 28 - 30°C and humidity of 75% - 80% and ferment for 60 - 90 minutes, and the volume expands to 2 - 2.5 times.

[0078] (9) Divide the fermented dough into 150 g per piece, round it up and let it rest and relax for 10 minutes; roll out the dough to exhaust air, roll it into a cylindrical shape or form it with a mold, and spray water mist on the surface to prevent cracking.

[0079] (10) The formed dough is fermented in an environment of 35 - 38°C and humidity of 80% - 85% for 40 - 50 minutes, and its volume increases to 1.8 - 2 times; the dough is taken out for baking, baked at 180°C on the upper fire / 150°C on the lower fire for 25 minutes, cooled in a ventilated environment at 25°C until the central temperature ≤ 30°C, and stored at room temperature.

[0080] Control Examples 1 - 3

[0081] The difference from Examples 1 - 3 is that direct structuring treatment is carried out with soybean oil without transesterification treatment.

[0082] Control Example 4

[0083] Soybean oil and palm stearin are mixed in a proportion of 30% saturation, dehydrated under vacuum at 65°C for 1 hour, and cooled to 45°C - 65°C; immobilized lipase is added, and the reaction is carried out under vacuum at 70 r / min for 3 hours, and the obtained mixed oil and fat is directly embedded. That is, no intermediate oil and fat structuring treatment is carried out.

[0084] Control Example 5

[0085] The difference from Examples 1 - 3 is that butter is used instead of powder oil and fat to prepare bread.

[0086] To further illustrate the technical effects of the solution of the present invention, the physical and chemical qualities of the powder oil and fat prepared in some examples and the breads prepared in the examples and control examples are analyzed through tests below.

[0087] Test Example 1. Solid Fat Content Test of Structured Oil and Fat

[0088] Taking the structured oil and fat prepared in Example 1, Example 2, and Example 3 as test samples to measure the solid fat content. Weigh 4 g of the sample and put it into a nuclear magnetic tube, and measure the solid fat content of the oil and fat at 20°C through low-field nuclear magnetic resonance, and compare it with the solid fat content of Control Examples 1 - 3. The test results are shown in Figure 1 .

[0089] Through Figure 1 the test results, it can be seen that at 20°C, the solid fat content of Control Example 4 is much lower than that of Examples 1 - 3 and Control Examples 1 - 3. It shows that without the structuring treatment of the gel factor, the solid fat content is relatively low, only 2.35%. At this time, the oil and fat is in a liquid state, and this relatively low solid fat content is not sufficient to support subsequent processing. Through the oil and fat gel crystallization regulation technology, the fat crystallization is further improved to obtain the results of Examples 1 - 3, and their solid fat contents (SFC) are 13.74%, 13.77%, and 9.07% respectively.

[0090] In addition, compared with Comparative Examples 1-3, the SFC of Examples 1-3 increased by 40.63%, 30.02%, and 20.93%. The SFC is positively correlated with the amount of oil crystallization. After double structuring, the SFC of the oil is higher than that of the soy oil with single gel structuring, indicating that the double structuring significantly improves the regulation of the crystallization amount compared to single gel structuring. In addition, when baking oil at 20 °C, the required SFC is higher than 10% to meet the plastic requirements of oil processing. The SFC of the comparative example cannot meet this requirement, and the SFC of the oil after double structuring > 10%, indicating that the oil meets the processing plasticity, further demonstrating that the processing characteristics of the oil after double structuring are superior to those of single gel regulation. This verifies the optimization effect of the double structuring process on the processing characteristics of oil (such as ductility and high-temperature shape retention), and adapts to the plastic requirements of dough forming, rolling, and high-temperature baking in the baking industry.

[0091] Test Example 2, Macroscopic Test of Powdered Oil

[0092] The powdered oils prepared in Examples 1, 2, and 3 were used as test samples for observation. The powdered oils obtained in Examples 1-3 were taken and evenly spread in a clean petri dish with a uniform thickness (2 ± 0.2 mm). The surface of the sample was vertically photographed using a high-definition digital camera under standard light source. The test results are shown in Figure 2 .

[0093] From Figure 2 the test results, it can be seen that Examples 1, 2, and 3 are all milky white, with a smooth surface, fine powder texture, and good fluidity, indicating that the present invention can successfully prepare powdered oil.

[0094] Test Example 3, Physicochemical Property Test of Powdered Oil

[0095] The powdered oils prepared in Examples 1, 2, and 3 were used as test samples to determine the encapsulation rate and moisture content of the samples. Weigh 1 g of powdered oil, add 50 mL of petroleum ether (boiling range 30-60 °C), stir magnetically for 30 minutes and then filter to collect the unencapsulated oil. The total amount of oil was determined by the Soxhlet extraction method, and the encapsulation rate (%) was calculated. Weigh 2 g of the sample and dry it in an oven at 105 °C until constant weight, and calculate the difference before and after drying as the moisture content. The test results are shown in Figure 3 .

[0096] From Figure 3 the test results, it can be seen that the encapsulation rates of Examples 1, 2, and 3 can all reach more than 80%. Among them, Example 1 has the highest encapsulation rate, proving that the synergistic effect of oil structuring and microencapsulation technology is beneficial to improving the encapsulation rate; the moisture content ranges of the samples of Examples 1, 2, and 3 are 1.5 - 3.0%, and the moisture content is lower than 4 g / 100 g, meeting the physicochemical stability of the microcapsules during storage. Test Example 4, XRD Test of the Oil Phase of Powdered Oil

[0097] Using the powder oils and fats prepared in Example 1, Example 2, and Example 3 as test samples, the crystal forms of the samples were determined. The oil phases of the powder oils and fats in Example 1-3 and the control example (after the solvent was volatilized by extraction with petroleum ether) were evenly coated on glass slides; through X-ray diffractometer testing, the positions of the diffraction peaks were observed and analyzed. The test results are shown in Figure 4 .

[0098] From Figure 4 the test results, it can be seen that diffraction peaks appeared at short spacings of 0.45 nm, 0.38 nm, and 0.42 nm in Example 1, Example 2, and Example 3 compared to the control example 4, indicating that their main crystal forms are β-type and β'-type, showing that the crystal forms required for baked goods exist in the powder oils and fats prepared by the present invention. Among them, in Example 1 and Example 2, there were obvious diffraction peaks at short spacings of 0.42 and 0.38 compared to the control example 4, and the diffraction peaks were narrow and thin, indicating a large amount of β'-crystallization. It can be proved that compared with single structuring, double structuring not only increases the crystallization amount, but also can induce the β'-crystal form by using specific gelling agents to meet the requirements of baking fats. It can be seen from the figure that after crystallization regulation, the contents of the β'-type are in the order of Example 2, Example 1, and Example 3. The content of the β'-type is positively correlated with the baking quality, indicating that through different gelling agents, the oil crystal network is used to directionally regulate the β'-crystal form of the oil, inducing the formation of a high proportion of β'-crystal form, and its fine crystals are evenly dispersed in the dough, significantly improving the bread specific volume and anti-aging property, and improving the product texture and shelf life.

[0099] Test Example 5, Bread Quality Test

[0100] Using the breads prepared with the powder oils and fats prepared in Example 1, Example 2, and Example 3 and the bread of the control example 5 as test samples, macroscopic observation and bread quality determination of the breads were carried out. After the breads prepared in Example 1-3 and the control example were cooled, they were placed on the table, and the cross-sectional structure was photographed using a standard light source. The test results are shown in Figure 5 .

[0101] The rapeseed displacement method was used to record the bread volume (mL), and the bread mass (g) was accurately weighed to calculate the bread specific volume.

[0102] From Figure 5-6From the test results, the effects of the powder fats and oils prepared in Examples 1-3 when applied to bread were compared with those of Comparative Examples 4-5. The crusts of all the bread were golden yellow, uniform, without spots, and the shapes were intact. However, the surfaces were rough and had cracks, which might be due to the relatively low moisture content. There were no obvious differences between Examples 1-3 and Comparative Examples 4-5 in macroscopic observation. Further evaluating the specific volume of the bread, the specific volumes of the bread from large to small were Example 2, Comparative Example 5, Example 1, Example 3, and Comparative Example 4, indicating that the double crystallization regulation increased the amount of crystal compared with the transesterification regulation, manifested as a larger specific volume and more fluffy bread. The fluffiness of the bread prepared with the powder fat and oil after crystallization regulation was similar to that of the butter bread. Among them, Example 2 had the largest specific volume, which was positively correlated with its β′-type content, proving that the β'-crystal form enhanced powder fat and oil could effectively replace butter to achieve a similar fluffiness and meet the requirement of zero trans fatty acids at the same time.

[0103] Obviously, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the technical solutions of the present invention, rather than limitations on the specific implementation manners of the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the claims of the present invention shall be included within the protection scope of the claims of the present invention.

Claims

1. A method for preparing a low-saturated fatty acid powder oil with a β' crystal form, characterized in that: The steps include: S1, mixing the oil and palm stearin, dehydrating and cooling; then adding immobilized lipase to react to obtain low saturated fatty acid transesterified oil; S2, mixing the obtained low-saturated fatty acid transesterified oil with a gel factor to prepare an oil phase; S3, dissolving the wall material and the core material in water to form an aqueous phase; S4, mixing the oil phase with the water phase to form an emulsion and then drying to obtain the low saturated fatty acid powdered oil.

2. The method for preparing the low-saturated fatty acid powdered oil with regulated β' crystal form according to claim 1, characterized in that: The oil is one or more of sunflower oil, soybean oil, rice bran oil, corn oil, fish oil, olive oil, glycerin, grape seed oil, and peanut oil.

3. The method for preparing the low-saturated fatty acid powdered oil with regulated β' crystal form according to claim 1, characterized in that: The immobilized lipase is sn-1,3 specific immobilized lipase.

4. The method for preparing the low-saturated fatty acid powdered oil with regulated β' crystal form according to claim 1, characterized in that: The saturation level in low saturated fatty acid transesterified oils is less than 40%.

5. The method for preparing the low-saturated fatty acid powdered oil with regulated β' crystal form according to claim 1, characterized in that: The gelling factor is one or more of beeswax, rice bran wax, ceramide, sitosterol, oryzanol, palmitic acid and ethyl cellulose.

6. The method for preparing the low-saturated fatty acid powdered oil with regulated β' crystal form according to claim 5, characterized in that: The concentration of the gel factor in the oil phase is 0.1% to 10%.

7. The method for preparing the low-saturated fatty acid powdered oil with regulated β' crystal form according to claim 6, characterized in that: The wall material is one or more of maltodextrin, modified starch, gum arabic, soy protein isolate, and whey protein; the emulsifier is one or more of sucrose fatty acid ester, soy lecithin, sunflower lecithin, whey protein, and sodium alkenyl succinate starch.

8. The method for preparing the low-saturated fatty acid powdered oil with regulated β' crystal form according to claim 1, characterized in that: The weight ratio of the core material to the wall material is 1:1 to 1:10; the content of the oil phase in the emulsion is 10% to 30%.

9. A powdered fat obtained by the method for preparing a low-saturated fatty acid powdered fat with controlled β' crystal form according to claim 1.

10. Use of the powdered fat according to claim 9 in food processing.

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