Rice bran oat low gi meal replacement bar and method of making same

Abstract

The application discloses a kind of rice bran oat low GI meal replacement bar and its preparation method, belong to food processing technical field.The raw materials of the rice bran oat low GI meal replacement bar include rice bran powder, oat, composite modified resistant starch, wheat flour, maltitol liquid, coconut oil and salt;Among them, the composite modified resistant starch includes sea red rice bran functional component liquid, oat starch and wheat starch.The rice bran oat low GI meal replacement bar relies on the composite dietary fiber of high content oat and rice bran powder, and is matched with composite modified resistant starch natural sugar control, and the product forming property, edible taste and low GI functional characteristics are considered.The preparation method of the rice bran oat low GI meal replacement bar is low-temperature baking throughout the process, without high-temperature puffing, without frying process, to the greatest extent to retain oat beta-glucan, rice bran active substance and composite modified resistant starch hypoglycemic active ingredient;Production equipment is conventional, process is simple, convenient laboratory test and factory scale production.

Description

Technical Field

[0001] This invention belongs to the field of food processing technology, specifically relating to a low-GI rice bran and oat meal replacement bar and its preparation method. Background Technology

[0002] With the increasing health awareness of the public, the number of people seeking weight loss and blood sugar control continues to expand, making low-GI, long-lasting satiety meal replacement bars the mainstream development direction for meal replacement foods. Existing oat meal replacement bars on the market generally suffer from three major drawbacks: First, refined oat flour degrades carbohydrates quickly, resulting in a GI value generally higher than 55, leading to significant post-meal blood sugar fluctuations and failing to meet the blood sugar control needs of people with diabetes or those trying to lose weight. Second, single-origin oat ingredients have limited dietary fiber variety, resulting in a short duration of satiety, with hunger easily returning 2-3 hours after consumption. Third, to improve the rough texture of grains, products generally add large amounts of malt syrup, white sugar, and vegetable oil, further raising blood sugar and contradicting the original design intent of low-calorie, low-GI products.

[0003] Rice bran is a byproduct of rice processing. It is rich in insoluble dietary fiber, γ-oryzanol, and resistant starch, which can effectively slow down the digestion and absorption of carbohydrates. At the same time, the raw material is cheap and readily available. Currently, the utilization rate of rice bran byproducts in the rice processing industry is extremely low, resulting in serious waste of resources.

[0004] In existing technologies, conventional grain meal replacement bars generally suffer from problems such as a dry and hard texture, a strong grassy taste, poor sugar control, and a monotonous flavor. Therefore, developing a low-GI rice bran and oat meal replacement bar made from natural ingredients, without added refined sugar, with a soft and palatable texture, and providing long-lasting satiety has extremely high market application value. Summary of the Invention

[0005] The first objective of this invention is to provide a low-GI rice bran oat meal replacement bar that solves the technical problems of existing grain meal replacement bars, such as poor shaping, easy crumbling, high GI value, added refined sugar, dry and rough taste, and weak sugar control effect.

[0006] The second objective of this invention is to provide a method for preparing a low-GI rice bran oat meal replacement bar.

[0007] To achieve the above objectives, the technical solution of the present invention is as follows: In a first aspect, the present invention provides a low-GI rice bran and oat meal replacement bar, the raw materials of which include rice bran powder, oats, compound modified resistant starch, wheat flour, maltitol liquid, coconut oil and salt; wherein, the compound modified resistant starch includes sea buckthorn rice bran functional component liquid, oat starch and wheat starch.

[0008] Furthermore, the preparation steps of the sea buckthorn rice bran functional component liquid include: preparing sea buckthorn rice bran powder into a sea buckthorn rice bran suspension of 9-11 w / v%, adjusting the pH to 5.4-5.6, then adding xylanase and cellulase for enzymatic hydrolysis, cooling to 36-38℃ and inoculating with Lactobacillus plantarum for fermentation, centrifuging to collect the supernatant after fermentation, and concentrating it to obtain the product.

[0009] Furthermore, the xylanase has an enzyme activity of (300-500) U / g, and the mass ratio of the xylanase to the sea buckthorn rice bran powder is 1.5-2.0%; the cellulase has an enzyme activity of (100-200) U / g, and the mass ratio of the cellulase to the sea buckthorn rice bran powder is 1.0-1.5%; the volume of the *Lactobacillus plantarum* is 2-4% of the volume of the sea buckthorn rice bran suspension.

[0010] Furthermore, the enzymatic hydrolysis step includes enzymatic hydrolysis at 49–51 °C for 3.5–4 h, followed by enzyme inactivation at 94–96 °C for 9–10 min; the fermentation temperature is 36–38 °C, and the fermentation time is 22–24 h.

[0011] Furthermore, the preparation steps of the composite modified resistant starch include: mixing oat starch and wheat starch at a mass ratio of 3:(3-7) and preparing a starch milk of 24-26 w / v%, gelatinizing the starch milk at 94-96 ℃ for 25-30 min, cooling it to 79-81 ℃ and adding the sea buckthorn rice bran functional component liquid, keeping it warm and stirring for 25-30 min, then aging it at 3-5 ℃ for 22-24 h, freeze-drying it after freeze-thaw cycles, and pulverizing it to obtain the final product.

[0012] Furthermore, the mass ratio of the sea buckthorn rice bran functional component liquid to the total mass of oat starch and wheat starch is (0.1~0.28):1; the freeze-thaw cycle procedure includes freezing at -21~-19 ℃ for 10~12 h and then thawing at 24~26 ℃ for 5~6 h, and the number of freeze-thaw cycles is 2~3 times.

[0013] Furthermore, the mass ratio of wheat flour to rice bran flour is 1:(1-5), the mass ratio of wheat flour to composite modified resistant starch is 1:(0.3-0.8), the mass ratio of the total mass of wheat flour and rice bran flour to the mass of oats is 1:(1-3), the mass ratio of wheat flour to maltitol liquid is 4:(1-5), the mass ratio of wheat flour to coconut oil is (15-25):1, and the mass ratio of wheat flour to salt is 10:(0.5-1).

[0014] Secondly, the present invention provides a method for preparing the rice bran and oat low-GI meal replacement bar as described above, comprising the following steps: Step 1: Mix the wheat flour, rice bran powder and oats according to the formula to achieve a complete and uniform mixture of the three grain powders, and obtain the compound grain dry material; Step 2: Add the coconut oil, maltitol solution, composite modified resistant starch and salt to the composite grain dry material obtained in Step 1, stir, so that the oil, maltitol solution and grain powder are fully soaked to form a composite material blank with moderate softness and hardness, good plasticity, no cracking and no looseness, and obtain the composite material blank. Step 3: Fill the mold with the composite material blank obtained in Step 2, press it into shape, and bake it to obtain rice bran oat low-GI meal replacement bars.

[0015] Furthermore, before mixing wheat flour, rice bran powder and oats in step 1, the process also includes passing wheat flour and rice bran powder through an 80-mesh standard sieve to remove lumps and large particles, ensuring the fineness of the powder and improving the uniformity of subsequent mixing.

[0016] Furthermore, the stirring and dry mixing time in step 1 is 5 to 7 minutes; the stirring time in step 2 is 5 to 7 minutes, and the stirring temperature is 34 to 36 ℃; the composite modified resistant starch in step 2 is also pre-dissolved before being added.

[0017] Furthermore, the composite modified resistant starch described in step 2 is pre-dissolved before being added.

[0018] Furthermore, the baking temperature in step 3 is 159–161 °C, and the baking time is 13–15 min.

[0019] The beneficial effects of this invention are: The rice bran oat low-GI meal replacement bar of this invention does not contain refined added sugars such as white sugar, sucrose, and glucose. It contains no artificial flavors, no artificial colors, and no chemical preservatives. It relies on the flavor of the raw materials themselves and maltitol liquid to adjust the taste. It is lower in calories and will not cause drastic fluctuations in blood sugar, which meets the current consumer demand for healthy sugar-free foods.

[0020] In this invention, the rice bran oat low-GI meal replacement bar utilizes a functional component liquid of *Salix matsudana* obtained through enzymatic hydrolysis and fermentation to participate in the preparation of composite modified resistant starch. Compared to the traditional method of using pure water as the reaction medium, the functional component liquid of *Salix matsudana* contains oligosaccharides, organic acids, soluble dietary fiber degradation products, and phenolic compounds, which play a positive role in the starch modification process. The functional component liquid of *Salix matsudana* can promote the formation of resistant starch. The oligosaccharides, organic acids, and phenolic compounds in the functional component liquid can participate in the starch gelatinization, aging, and retrogradation processes, which is beneficial for the rearrangement and orderly aggregation of starch chains, thereby promoting the formation of resistant starch and increasing the resistant starch content in the product. The functional component liquid of *Salix matsudana* can reduce the starch digestion rate. The oligosaccharides, soluble dietary fiber degradation products, and fermentation metabolites in the functional component liquid can work together with starch to reduce the efficiency of digestive enzymes on starch, slow down the starch hydrolysis rate, and improve the enzymatic resistance of starch, thus helping to lower the glycemic index of the product. Sea buckthorn rice bran functional component liquid can improve the nutritional quality of products. Soluble active ingredients such as ferulic acid and free phenols in the liquid can be partially retained in the resistant starch system, increasing the content of resistant starch while simultaneously increasing the content of natural active ingredients and improving the product's nutritional quality. Sea buckthorn rice bran functional component liquid can also enhance the utilization value of rice bran resources. Using the functional components obtained from the enzymatic hydrolysis and fermentation of sea buckthorn rice bran for resistant starch preparation achieves effective utilization of the functional components in rice bran, increases the added value of the product, and provides a new approach for the high-value utilization of rice bran by-products.

[0021] In the rice bran and oat low-GI meal replacement bar of this invention, a high proportion of oats combined with rice bran provides dual dietary fiber to physically block starch digestion, maximizing the dietary fiber content of the grains and enhancing the satiety effect; rice bran combined with wheat flour balances dietary fiber supplementation and dough binding and shaping properties; combined with compound modified resistant starch to inhibit glycosidase activity, it achieves dual internal and external sugar control, with a measured GI value of ≤55, which is a compliant low-GI food and suitable for people with high blood sugar and those trying to lose weight to consume as a meal replacement.

[0022] In the rice bran and oat low-GI meal replacement bar of the present invention, a trace amount of coconut oil masks the bitter taste of rice bran itself, and maltitol liquid provides a mild sweetness without the cloying sweetness of sucrose. The overall grain aroma is rich, not dry or rough, and has a smooth chewing texture. Its palatability is far superior to that of ordinary sugar-free grain meal replacement bars.

[0023] The preparation method of the rice bran oat low-GI meal replacement bar of the present invention involves low-temperature baking throughout the process, without high-temperature puffing or frying, thus preserving oat β-glucan, rice bran active substances, and the hypoglycemic active ingredients of the composite modified resistant starch to the greatest extent. The production equipment is conventional, the process is simple, and it is convenient for laboratory testing and large-scale factory production. Attached Figure Description

[0024] Figure 1 The sensory evaluation results of the rice bran and oat low-GI meal replacement bar in Experiment Example 1; Figure 2 The sensory evaluation results of the rice bran and oat low-GI meal replacement bar in Experiment Example 2; Figure 3 The sensory evaluation results of the rice bran and oat low-GI meal replacement bar in Experiment Example 3; Figure 4 The sensory evaluation results are for the rice bran and oat low-GI meal replacement bar of Experiment Example 4. Detailed Implementation

[0025] In the following examples, the sea buckthorn rice bran powder used was purchased from Wenzhou, Zhejiang; the wheat flour used was Wudeli wheat flour; the maltitol liquid used was purchased from Shandong Shuntian Food Co., Ltd.; the coconut oil used was Qiongnan coconut oil; the salt used was commercially available edible salt; and the oats used were commercially available oats.

[0026] In the following examples, the GI value was determined using the following method: Determination of in vitro glycemic index (GI) 1. In vitro simulated digestion Accurately weigh 1.0 g of pulverized and sieved low-GI rice bran and oat meal replacement bar powder, add 5 mL of distilled water and mix well; add the simulated salivary α-amylase system sequentially, and mechanically homogenize to simulate oral chewing; adjust the pH of the system to 1.5, add simulated gastric juice, and shake at 37 ℃ in the dark to simulate gastric digestion; then neutralize with NaOH, add phosphate buffer and pancreatic enzyme, and shake at 37 ℃ and 200 r / min in the dark to carry out small intestinal digestion.

[0027] Take 3 mL samples at 0, 20, 60, 120 and 180 min in the small intestine for digestion, respectively, and terminate the enzymatic reaction by boiling water bath; centrifuge at 8000 r / min for 10 min and collect the supernatant.

[0028] 2. Glucose content detection and GI value calculation The glucose concentration in the supernatant of each group was determined by the glucose oxidase method (GOD-POD), and the cumulative glucose release at different digestion times was calculated.

[0029] Using white bread of equal quality (standard control, GI benchmark=100) as the standard, the above-mentioned complete in vitro digestion, sampling and testing process was completely replicated, and the glucose release of white bread at each time point was measured simultaneously.

[0030] Glucose cumulative release curves were plotted for the meal replacement bar sample and the white bread standard, respectively. The area under the two curves (AUC) within the 0–180 min digestion interval was calculated using the trapezoidal integral method. The hydrolysis index was calculated according to Formula I.

[0031] Hydrolysis index HI (%) = (AUC sample / AUC white bread) × 100, Equation I.

[0032] The in vitro glycemic index (GI) is calculated according to Formula II.

[0033] eGI=8.1981+0.862×HI, formula II.

[0034] The following will provide further details with reference to embodiments of the present invention.

[0035] Example 1 The ingredients of the low-GI rice bran oat meal replacement bar in Example 1 include: 10 g wheat flour, 10 g rice bran powder, 30 g oats, 7.5 g maltitol liquid, 0.5 g coconut oil, 5 g compound modified resistant starch and 0.5 g salt; wherein, the rice bran powder used is sea buckthorn rice bran powder.

[0036] The preparation steps of the composite modified resistant starch include: 100 g of sea buckthorn rice bran powder was used to prepare a 10 w / v% sea buckthorn rice bran suspension. The pH was adjusted to 5.5, and then 2 g of xylanase (400 U / g) and 1 g of cellulase (100 U / g) were added. Enzymatic hydrolysis was carried out at 50 ℃ for 4 h. After hydrolysis, the enzymes were inactivated at 95 ℃ for 10 min. The mixture was then cooled to 37 ℃, inoculated with 3 mL of Lactobacillus plantarum, and fermented at 37 ℃ for 24 h. After fermentation, the supernatant was collected by centrifugation and concentrated to 1 / 3 of the original volume to obtain the sea buckthorn rice bran functional component solution.

[0037] Mix 50 g of oat starch and 50 g of wheat starch to prepare a 25 w / v% starch slurry. Gelatinize the starch slurry at 95℃ for 30 min, cool to 80℃, and then add 28 g of the obtained sea buckthorn rice bran functional component solution. Keep warm and stir for 30 min, then age at 4℃ for 24 h, freeze at -20℃ for 12 h, and thaw at 25℃ for 6 h, repeating this cycle 3 times. Finally, freeze-dry, pulverize, and pass through a 100-mesh sieve to obtain the composite modified resistant starch.

[0038] The preparation method of the rice bran and oat low-GI meal replacement bar in Example 1 includes the following steps: Wheat flour and sea buckthorn rice bran powder were passed through an 80-mesh standard sieve to remove lumps and large particles, ensuring fine powder texture and improving the uniformity of subsequent mixing. The prescribed amounts of wheat flour, sea buckthorn rice bran powder, and oats were then mixed dry to achieve complete and uniform mixing of the three grain powders, resulting in a compound grain dry material.

[0039] Mix the prescribed amount of compound modified resistant starch with 100g of water to pre-dissolve it into a compound modified resistant starch solution. Add the prescribed amount of coconut oil, maltitol solution, the pre-dissolved compound modified resistant starch solution, and salt to the obtained compound grain dry material, stir, and allow the oil, maltitol solution, and the obtained compound grain dry material to fully impregnate, forming a compound preform with moderate softness and hardness, good plasticity, and without cracking or looseness.

[0040] The obtained composite material blanks are filled into a special mold for meal replacement bars and pressed at room temperature to form uniform long strips of meal replacement bar blanks with consistent specifications. The formed meal replacement bar blanks are placed in a hot air oven and baked at 160 ℃ for 15 minutes. After baking, the moisture content of the rice bran and oat low-GI meal replacement bars is controlled at 8-10%. After baking, the meal replacement bars are removed, cooled to room temperature at 25 ℃, and then vacuum-packed individually to obtain the rice bran and oat low-GI meal replacement bars.

[0041] The low-GI rice bran oat meal replacement bar of Example 1 was prepared by the preparation method of the low-GI rice bran oat meal replacement bar of Example 1. The resulting low-GI rice bran oat meal replacement bar had a GI value of 41 and a moisture content of 8-10%.

[0042] Example 2 The ingredients of the low-GI rice bran oat meal replacement bar in Example 2 include: 10 g wheat flour, 30 g rice bran powder, 40 g oats, 2.5 g maltitol liquid, 0.4 g coconut oil, 3 g composite modified resistant starch and 1 g salt; wherein, the rice bran powder used is sea buckthorn rice bran powder.

[0043] The preparation steps of the composite modified resistant starch include: 100 g of sea buckthorn rice bran powder was used to prepare a 10 w / v% sea buckthorn rice bran suspension. The pH was adjusted to 5.5, and then 2 g of xylanase (400 U / g) and 1 g of cellulase (100 U / g) were added. Enzymatic hydrolysis was carried out at 50 ℃ for 4 h. After hydrolysis, the enzymes were inactivated at 95 ℃ for 10 min. The mixture was then cooled to 37 ℃, inoculated with 3 mL of Lactobacillus plantarum, and fermented at 37 ℃ for 24 h. After fermentation, the supernatant was collected by centrifugation and concentrated to 1 / 3 of the original volume to obtain the sea buckthorn rice bran functional component solution.

[0044] 30 g of oat starch and 70 g of wheat starch were mixed to prepare a 25 w / v% starch slurry. The starch slurry was gelatinized at 95 °C for 30 min, cooled to 80 °C, and then 18 g of the obtained sea buckthorn rice bran functional component solution was added. The mixture was kept warm and stirred for 30 min, then aged at 4 °C for 24 h, frozen at -20 °C for 12 h, and thawed at 25 °C for 6 h, repeated twice. Finally, the mixture was freeze-dried, pulverized, and passed through a 100-mesh sieve to obtain the composite modified resistant starch.

[0045] The preparation method of the rice bran and oat low-GI meal replacement bar in Example 2 includes the following steps: Wheat flour and sea buckthorn rice bran powder were passed through an 80-mesh standard sieve to remove lumps and large particles, ensuring fine powder texture and improving the uniformity of subsequent mixing. The prescribed amounts of wheat flour, sea buckthorn rice bran powder, and oats were then mixed dry to achieve a complete and uniform blend of the three grain powders, resulting in a compound grain dry material.

[0046] Mix the prescribed amount of modified resistant starch with 100 g of water to pre-dissolve it into a modified resistant starch solution. Add the prescribed amount of coconut oil, maltitol solution, the pre-dissolved modified resistant starch solution, and salt to the obtained composite grain dry material, stir, and allow the oil, maltitol solution, and the obtained composite grain dry material to fully impregnate them, forming a composite preform with moderate softness and hardness, good plasticity, and without cracking or looseness.

[0047] The obtained composite material blanks are filled into a special mold for meal replacement bars and pressed at room temperature to form uniform long strips of meal replacement bar blanks with consistent specifications. The formed meal replacement bar blanks are placed in a hot air oven and baked at 160 ℃ for 15 minutes. After baking, the moisture content of the rice bran and oat low-GI meal replacement bars is controlled at 8-10%. After baking, the meal replacement bars are removed, cooled to room temperature at 25 ℃, and then vacuum-packed individually to obtain the rice bran and oat low-GI meal replacement bars.

[0048] The low-GI rice bran oat meal replacement bar of Example 2 was prepared by the same method as the low-GI rice bran oat meal replacement bar of Example 2. The resulting low-GI rice bran oat meal replacement bar had a GI value of 46 and a moisture content of 8-10%.

[0049] Example 3 The ingredients of the low-GI rice bran oat meal replacement bar in Example 3 include: 10 g wheat flour, 50 g rice bran powder, 180 g oats, 12.5 g maltitol liquid, 0.66 g coconut oil, 8 g compound modified resistant starch and 1.0 g salt; wherein, the rice bran powder used is sea buckthorn rice bran powder.

[0050] The preparation steps of the composite modified resistant starch include: 100 g of sea buckthorn rice bran powder was used to prepare a 10 w / v% sea buckthorn rice bran suspension. The pH was adjusted to 5.5, and then 2 g of xylanase (400 U / g) and 1 g of cellulase (100 U / g) were added. Enzymatic hydrolysis was carried out at 50 ℃ for 4 h. After hydrolysis, the enzymes were inactivated at 95 ℃ for 10 min. The mixture was then cooled to 37 ℃, inoculated with 3 mL of Lactobacillus plantarum, and fermented at 37 ℃ for 24 h. After fermentation, the supernatant was collected by centrifugation and concentrated to 1 / 3 of the original volume to obtain the sea buckthorn rice bran functional component solution.

[0051] Mix 50 g of oat starch and 50 g of wheat starch to prepare a 25 w / v% starch slurry. Gelatinize the starch slurry at 95℃ for 30 min, cool to 80℃, and then add 18 g of the obtained sea buckthorn rice bran functional component solution. Keep warm and stir for 30 min, then age at 4℃ for 24 h, freeze at -20℃ for 12 h, and thaw at 25℃ for 6 h, repeating this cycle 3 times. Finally, freeze-dry, pulverize, and pass through a 100-mesh sieve to obtain the composite modified resistant starch.

[0052] The preparation method of the rice bran and oat low-GI meal replacement bar in Example 3 includes the following steps: Wheat flour and sea buckthorn rice bran powder were passed through an 80-mesh standard sieve to remove lumps and large particles, ensuring fine powder texture and improving the uniformity of subsequent mixing. The prescribed amounts of wheat flour, sea buckthorn rice bran powder, and oats were then mixed dry to achieve a complete and uniform blend of the three grain powders, resulting in a compound grain dry material.

[0053] Mix the prescribed amount of modified resistant starch with 100 g of water to pre-dissolve it into a modified resistant starch solution. Add the prescribed amount of coconut oil, maltitol solution, the pre-dissolved modified resistant starch solution, and salt to the obtained composite grain dry material, stir, and allow the oil, maltitol solution, and the obtained composite grain dry material to fully impregnate them, forming a composite preform with moderate softness and hardness, good plasticity, and without cracking or looseness.

[0054] The obtained composite material blanks are filled into a special mold for meal replacement bars and pressed at room temperature to form uniform long strips of meal replacement bar blanks with consistent specifications. The formed meal replacement bar blanks are placed in a hot air oven and baked at 160 ℃ for 15 minutes. After baking, the moisture content of the rice bran and oat low-GI meal replacement bars is controlled at 8-10%. After baking, the meal replacement bars are removed, cooled to room temperature at 25 ℃, and then vacuum-packed individually to obtain the rice bran and oat low-GI meal replacement bars.

[0055] The low-GI rice bran oat meal replacement bar of Example 3 was prepared by the preparation method of the low-GI rice bran oat meal replacement bar of Example 3. The resulting low-GI rice bran oat meal replacement bar had a GI value of 44 and a moisture content of 8-10%.

[0056] Single-factor experiments were conducted using four factors: oat content, rice bran powder content, maltitol liquid content, and coconut oil content. Each factor had five levels, while other factors remained constant. The sensory evaluation of the rice bran and oat low-GI meal replacement bars was conducted from five aspects: appearance, surface color, aroma, taste, and texture. The sensory scoring criteria are shown in Table 1.

[0057] Table 1 Sensory evaluation criteria for low-GI rice bran and oat meal replacement bars

[0058] Experimental Example 1 The preparation method of the rice bran oat low-GI meal replacement bar in Experimental Example 1 is largely the same as that in Example 1. The difference between the preparation method of the rice bran oat low-GI meal replacement bar in Experimental Example 1 and that in Example 1 is that the amounts of wheat flour, rice bran flour, maltitol liquid, coconut oil, composite modified resistant starch, and salt are controlled in the same way as in Example 1. Only the amount of oats is changed. The amounts of oats are 0 g, 10 g, 20 g, 30 g, and 40 g, respectively.

[0059] The sensory evaluation results of the rice bran and oat low-GI meal replacement bar in Experiment Example 1 are as follows: Figure 1 As shown, the rice bran oat low-GI meal replacement bar received the highest overall score for appearance and taste when the oat content was 30 g. As the core ingredient of the energy bar, the amount of oat directly affects the structural characteristics and eating experience of the rice bran oat low-GI meal replacement bar: when the oat content is insufficient, the proportion of dietary fiber and grain matrix in the raw material system is low, resulting in insufficient surface smoothness, uneven texture, and decreased appearance regularity after product molding; while when the oat content is high, excessive dietary fiber will damage the colloidal network structure of the dough, weakening the binding force between ingredients. This not only leads to a harder texture and increased chewing resistance after baking, but also causes difficulty in adhesion due to uneven oat particle dispersion, resulting in crumbs and easy breakage. The 30 g addition amount ensures both the loose texture and natural grain color of the oats, while maintaining good dough formability, achieving a balance between appearance and taste.

[0060] Experimental Example 2 The preparation method of the low-GI rice bran oat meal replacement bar in Experiment 2 is largely the same as that in Example 1. The difference between the preparation method of the low-GI rice bran oat meal replacement bar in Experiment 2 and that in Example 1 is that the amounts of wheat flour, maltitol solution, oats, coconut oil, modified resistant starch and salt are controlled in the same way as in Example 1, only the amount of rice bran powder is changed. The amounts of rice bran powder are 0 g, 5 g, 10 g, 15 g and 20 g respectively.

[0061] The sensory evaluation results of the rice bran and oat low-GI meal replacement bars in Experiment Example 2 are as follows: Figure 2 As shown, 10 g of rice bran is the optimal ratio, which ensures both the quality and cost-effectiveness of the low-GI rice bran oat meal replacement bars. Sensory analysis reveals significant drawbacks in low-GI rice bran oat meal replacement bars using 20 g of rice bran powder: the phytic acid and dietary fiber in rice bran powder contribute a noticeable astringent taste; its low protein and starch content prevents the formation of a stable dough structure, leading to difficulty in shaping; rapid moisture loss after baking results in an overly dry, brittle, and easily crumbled product; as the amount of rice bran powder increases, its flavonoids and polyphenols darken the color of the energy bars, resulting in a dark brown color with excessive addition, reducing visual appeal; and the high dietary fiber content increases swallowing difficulty, causing a foreign body sensation in the throat. From a cost perspective, a 1:1 ratio of rice bran powder to wheat flour effectively reduces raw material costs without compromising the product's nutritional density, meeting the economic requirements of industrial production.

[0062] Experimental Example 3 The preparation method of the rice bran and oat low-GI meal replacement bar in Experiment 3 is largely the same as that in Example 1. The difference between the preparation method of the rice bran and oat low-GI meal replacement bar in Experiment 3 and that in Example 1 is that the amounts of wheat flour, rice bran flour, oats, coconut oil, composite modified resistant starch, and salt are controlled in the same way as in Example 1. Only the amount of maltitol solution is changed. The amounts of maltitol solution are 0 g, 2.5 g, 5 g, 7.5 g, and 10 g, respectively.

[0063] The sensory evaluation results of the rice bran and oat low-GI meal replacement bars in Experiment Example 3 are as follows: Figure 3As shown, the product exhibits the best overall sensory performance when maltitol liquid is added at a concentration of 7.5 g. Maltitol liquid acts as a functional sweetener and binder, with its mechanism of action manifested in two aspects: Firstly, its excellent viscosity allows it to fill the gaps between oat and rice bran particles, enhancing the interfacial bonding between raw materials and effectively improving the adhesion problem caused by excessive oats, thus enhancing product structural stability. Secondly, its low glycemic index (GI) meets the development requirements of health foods. When the amount of maltitol liquid added is less than 15%, the viscosity is insufficient, resulting in poor adhesion of raw materials and a loose product. Conversely, when the amount exceeds 15%, the excessive sugar alcohol increases the sweetness of the low-GI rice bran and oat meal replacement bars. Furthermore, its hygroscopic nature leads to a greasy and sticky texture, reducing the enjoyment of eating. This is related to the physical properties and taste threshold of maltitol liquid.

[0064] Test Example 4 The preparation method of the rice bran oat low-GI meal replacement bar in Experiment 3 is roughly the same as that in Example 1. The difference between the preparation method of the rice bran oat low-GI meal replacement bar in Experiment 3 and that in Example 1 is that the amounts of wheat flour, rice bran flour, oats, maltitol solution, composite modified resistant starch, and salt in Experiment 3 are the same as in Example 1. Only the amount of coconut oil is changed. The amounts of coconut oil are 0 g, 0.5 g, 1 g, 1.5 g, and 2 g, respectively.

[0065] The sensory evaluation results of the rice bran and oat low-GI meal replacement bar in Experiment Example 4 are as follows: Figure 4 As shown, the optimal sensory effect is achieved when 0.1g of coconut oil is added. The medium-chain fatty acids in coconut oil give the product a unique coconut flavor, while also acting as a lubricant to improve the dough's extensibility and the product's smoothness. Too little coconut oil results in a dry texture and poor chewiness; too much, however, causes an overabundance of sweet substances in the coconut oil, leading to an overly prominent sweetness that masks the natural flavors of oats and rice bran. Excessive oil also makes the product greasy and leaves a sticky feeling in the mouth, disrupting the flavor balance. Adding 0.1g provides a subtle coconut aroma while maintaining a refreshing taste and preventing flavor imbalance.

Claims

1. A low-GI meal replacement bar made from rice bran and oats, characterized in that, The raw materials include rice bran powder, oats, compound modified resistant starch, wheat flour, maltitol liquid, coconut oil, and salt; wherein the compound modified resistant starch includes sea buckthorn rice bran functional component liquid, oat starch, and wheat starch.

2. The rice bran and oat low-GI meal replacement bar according to claim 1, characterized in that, The preparation steps of the sea buckthorn rice bran functional component liquid include: preparing sea buckthorn rice bran powder into a sea buckthorn rice bran suspension of 9-11 w / v%, adjusting the pH to 5.4-5.6, then adding xylanase and cellulase for enzymatic hydrolysis, cooling to 36-38℃ and inoculating with Lactobacillus plantarum for fermentation, centrifuging to collect the supernatant after fermentation, and concentrating it to obtain the product.

3. The rice bran and oat low-GI meal replacement bar according to claim 2, characterized in that, The xylanase has an enzyme activity of (300-500) U / g, and the mass ratio of the xylanase to sea buckthorn rice bran powder is 1.5-2.0%; the cellulase has an enzyme activity of (100-200) U / g, and the mass ratio of the cellulase to sea buckthorn rice bran powder is 1.0-1.5%; the volume of the *Lactobacillus plantarum* is 2-4% of the volume of the sea buckthorn rice bran suspension.

4. The rice bran and oat low-GI meal replacement bar according to claim 2, characterized in that, The enzymatic hydrolysis step includes enzymatic hydrolysis at 49–51 °C for 3.5–4 h, followed by enzyme inactivation at 94–96 °C for 9–10 min; the fermentation temperature is 36–38 °C, and the fermentation time is 22–24 h.

5. The rice bran and oat low-GI meal replacement bar according to claim 1, characterized in that, The preparation steps of the composite modified resistant starch include: mixing oat starch and wheat starch at a mass ratio of 3:(3-7) and preparing a starch milk of 24-26 w / v%. The starch milk is gelatinized at 94-96 °C for 25-30 min, cooled to 79-81 °C, and then the sea buckthorn rice bran functional component liquid is added. The mixture is kept warm and stirred for 25-30 min, then aged at 3-5 °C for 22-24 h. After freeze-thaw cycles, it is freeze-dried and pulverized to obtain the final product.

6. The rice bran and oat low-GI meal replacement bar according to claim 5, characterized in that, The mass ratio of the sea buckthorn rice bran functional component liquid to the total mass of oat starch and wheat starch is (0.1-0.3):1; the freeze-thaw cycle procedure includes freezing at -21 to -19 ℃ for 10-12 h and then thawing at 24 to 26 ℃ for 5-6 h, and the number of freeze-thaw cycles is 2-3 times.

7. The rice bran and oat low-GI meal replacement bar according to claim 1, characterized in that, The mass ratio of wheat flour to rice bran flour is 1:(1-5), the mass ratio of wheat flour to compound modified resistant starch is 1:(0.3-0.8), the mass ratio of the total mass of wheat flour and rice bran flour to the mass of oats is 1:(1-3), the mass ratio of wheat flour to maltitol liquid is 4:(1-5), the mass ratio of wheat flour to coconut oil is (15-25):1, and the mass ratio of wheat flour to salt is 10:(0.5-1).

8. A method for preparing a low-GI rice bran and oat meal replacement bar as described in any one of claims 1 to 7, characterized in that, The process includes the following steps: Step 1: Mix the prescribed amounts of wheat flour, rice bran flour, and oats to obtain a compound grain dry mix; Step 2: Add the prescribed amounts of coconut oil, maltitol solution, compound modified resistant starch, and salt to the compound grain dry mix obtained in Step 1, and mix to obtain a compound preform; Step 3: Fill the compound preform obtained in Step 2 into a mold, press it into shape, and bake it to obtain a rice bran oat low-GI meal replacement bar.

9. The method for preparing the rice bran and oat low-GI meal replacement bar according to claim 8, characterized in that, The mixing time in step 1 is 5-7 min; the mixing time in step 2 is 5-7 min, and the mixing temperature is 34-36 ℃; the composite modified resistant starch in step 2 is also pre-dissolved before being added.

10. The method for preparing the rice bran and oat low-GI meal replacement bar according to claim 8, characterized in that, The baking temperature in step 3 is 159–161 °C, and the baking time is 13–15 min.

Images