A method for preparing a compound fruit and vegetable nutritious potato cake product

Abstract

This invention provides a method for preparing a compound fruit and vegetable nutritious sweet potato cake product, relating to the field of sweet potato cake preparation technology. The method specifically includes the following steps: S1. Fresh sweet potatoes are washed, steamed at 95-105℃ for 20-30 minutes, then rapidly cooled to -18~-22℃ and frozen for 2-4 hours. After thawing, the sweet potatoes are peeled. S2. The peeled sweet potatoes are enzymatically hydrolyzed for 20-40 minutes, and then 5%-10% of a compound fruit and vegetable puree and 0.2%-0.5% of a flavor precursor mixture are added. The mixture is stirred at high speed to form a uniform sweet potato puree. S3. The sweet potato puree is used as a base layer, and a compound fruit and vegetable interlayer and a nutrient microcapsule layer are sequentially injected through a microfluidic mold, controlling the thickness of each layer to be 0.5-2 mm, forming a composite structure blank. S4. The formed blank is vacuum pre-cooled at 0-4℃ for 10-20 minutes, then cut into pieces, weighed, packaged using modified atmosphere packaging, and finally stored at 2-6℃. Modified atmosphere packaging replaces freezing, significantly extending shelf life and optimizing palatability and nutrient retention.

Description

Technical Field

[0001] This invention relates to the field of potato cake preparation technology, specifically to a method for preparing a compound fruit and vegetable nutritious potato cake product. Background Technology

[0002] The compound fruit and vegetable nutritional potato cake product is made from sweet potatoes as the main raw material, combined with a variety of fruit and vegetable puree components, and is produced through processes such as molding and storage. It combines the characteristics of potato as a staple food with the nutritional advantages of fruits and vegetables, and can be used as a ready-to-eat nutritional supplement to meet the needs of modern consumers for convenient and functional diets.

[0003] Current processes for preparing compound fruit and vegetable sweet potato cakes typically involve washing, steaming, freezing, peeling, mashing, shaping, freezing, and packaging sweet potatoes, enriching the product's flavor and nutrition by adding fruit and vegetable purees. However, this process relies on frozen storage to maintain product quality, which leads to issues such as easy product aging, significant flavor degradation, and high cold chain costs. The aging of product texture and loss of flavor caused by frozen storage are the core bottlenecks restricting the product's ready-to-eat nature and extended shelf life. Summary of the Invention

[0004] Technical problems to be solved

[0005] To address the shortcomings of existing technologies, this invention provides a method for preparing compound fruit and vegetable nutritious potato cake products, which solves the problems of existing technologies relying on frozen storage, which easily leads to texture aging, flavor loss, and high cold chain costs.

[0006] Technical solution

[0007] To achieve the above objectives, the present invention provides the following technical solution: a method for preparing a compound fruit and vegetable nutritious potato cake product, specifically comprising the following steps:

[0008] S1. Sweet potato pretreatment

[0009] Wash the fresh sweet potatoes and steam them at 95-105℃ for 20-30 minutes. Then quickly cool them to -18~-22℃ and freeze them for 2-4 hours. After thawing, peel them.

[0010] S2. Enzymatic hydrolysis and modification to create mud.

[0011] Place the peeled sweet potatoes in a constant temperature environment of 32-38℃, add 0.1%-0.3% of pectinase and amylase compound enzyme solution by weight of sweet potatoes, and enzymatically hydrolyze for 20-40 minutes. Then add 5%-10% of compound fruit and vegetable puree and 0.2%-0.5% of flavor precursor mixture by weight of sweet potato puree, and stir at high speed to make uniform sweet potato puree.

[0012] S3. Layered molding

[0013] Using the mashed potato as a base layer, a composite fruit and vegetable interlayer and a nutrient microcapsule layer are sequentially injected through a microfluidic mold, with the thickness of each layer controlled to be 0.5-2mm, to form a composite structure blank.

[0014] S4. Freshness-locking treatment

[0015] The shaped blank is pre-cooled in a vacuum at 0-4℃ for 10-20 minutes, then cut into pieces, weighed, packaged in modified atmosphere packaging, and finally stored in a refrigerator at 2-6℃.

[0016] Preferably, in S1, the steamed sweet potatoes are cooled to below 60°C before freezing, and the freezing rate is controlled at 1-2°C / min.

[0017] Preferably, in S2, the mass ratio of pectinase to amylase is 1:1-2:1, and the flavor precursor mixture is a mixture of glutamine and glucose in a mass ratio of 1:1-1:2.

[0018] Preferably, in S2, the compound fruit and vegetable puree is made by mixing hawthorn puree, strawberry puree, and pumpkin puree in a mass ratio of 2:1:1.

[0019] Preferably, in S3, the nutrient microcapsule layer is an edible starch microcapsule encapsulating probiotics or dietary fiber, and the microcapsule particle size is 50-200μm.

[0020] Preferably, in S4, the modified atmosphere packaging is filled with a mixture of N2, CO2, and O2 in a volume ratio of 60:35:5, and the residual oxygen content in the packaging is ≤2%.

[0021] Preferably, in S4, the weight of a single piece of potato cake after cutting is 20-30g, and the shape is cuboid or cube.

[0022] A compound fruit and vegetable nutritious sweet potato cake product includes a product, which has a multi-layered composite structure, with a surface layer of sweet potato puree as the base and a compound fruit and vegetable layer and a nutrient microcapsule layer sandwiched in the middle.

[0023] Beneficial effects

[0024] This invention provides a method for preparing a compound fruit and vegetable nutritious potato cake product. It has the following beneficial effects:

[0025] This invention provides a method for preparing a compound fruit and vegetable nutritious sweet potato cake product. By treating sweet potato raw materials with low-temperature directional enzymatic hydrolysis, cell wall degradation is promoted, the release efficiency of flavor precursors is significantly improved, the flavor profile of the product is optimized, and the sensory quality of the product is enhanced. Furthermore, modified atmosphere packaging is used to replace traditional frozen storage, which significantly reduces the cold chain transportation cost of the product, optimizes the texture stability of the product, extends the shelf life of the product, and promotes the expansion of ready-to-eat application scenarios. Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] This invention provides an embodiment of a method for preparing a compound fruit and vegetable nutritious sweet potato cake product. All raw materials used in this embodiment comply with national food safety standards. The specific components and specifications are as follows: fresh Yanshu No. 25 sweet potato (starch content 18%-20%, crude fiber content ≤2.5%); mature hawthorn (soluble solids content ≥10%), fresh red-faced strawberry (soluble solids content ≥12%), mature pumpkin (starch content ≤6%); food-grade pectinase (enzyme activity 100,000 U / g), food-grade α-amylase (enzyme activity 200,000 U / g); food-grade L-glutamine, anhydrous glucose; Lactobacillus acidophilus probiotic microcapsules (encapsulation rate ≥85%, particle size 50-200 μm, viable count ≥10). 9 CFU / g); biodegradable PLA food packaging film, food-grade emulsified silicone oil (for demolding);

[0028] In addition, the main equipment and instruments include a fully automatic steam cooker, a tunnel-type quick-freezing machine, a constant temperature enzymatic hydrolysis box, a high-speed shearing sludge remover, a microfluidic layering molding die, a vacuum precooler, a modified atmosphere packaging machine, an electronic analytical balance (accuracy 0.01g), a texture analyzer, a gas chromatograph-mass spectrometer, an ultraviolet spectrophotometer, and a constant temperature and humidity incubator.

[0029] The specific implementation steps are as follows:

[0030] Sweet potato washing and grading pretreatment: Select 15kg of fresh sweet potatoes free from mold, insect infestation, and mechanical damage. Place them in a running water spray washing machine and rinse for 3 minutes to remove surface mud, residual pesticides, and impurities. After rinsing, manually remove moldy and deformed sweet potatoes and grade them according to individual weight of 200-300g to ensure even heating during subsequent steaming. The graded sweet potatoes are then placed in a steam cooker, and the temperature is controlled at 100℃ and the steam pressure at 0.1MPa. Steam at this constant temperature for 25 minutes, turning them every 5 minutes to ensure they are thoroughly cooked inside and out without any hard core. Grading and steaming promotes full gelatinization of the sweet potato starch, improves the fineness of the subsequent mashing process, avoids uneven cooking that results in a grainy texture in the mashed sweet potato, and optimizes the uniformity of the product's taste.

[0031] After steaming, the sweet potatoes were quickly transferred to an air-cooled cooling table, spread out, and cooled to 55°C. They were then immediately placed in a tunnel-type quick-freezing machine, with a freezing rate controlled at 1.5°C / min, and frozen at a constant temperature of -20°C for 3 hours to allow small, uniform ice crystals to form between the sweet potato cells. After freezing, the sweet potatoes were removed and thawed at room temperature and pressure for 15 minutes. Once the skin was slightly softened, mechanical roller pressing combined with manual assistance was used to remove the skin and roots, yielding 13.8 kg of peeled sweet potatoes. The peeling loss rate was controlled to within 8%. Gradient quick-freezing disrupts the adhesion between the sweet potato skin and flesh, reducing peeling difficulty and flesh loss, while also inhibiting starch retrogradation and preserving the soft, glutinous texture of the sweet potato flesh.

[0032] Low-temperature directional enzymatic hydrolysis and compound pulping: Peeled sweet potatoes are cut into 2cm×2cm pieces and placed in a 35℃ constant temperature enzymatic hydrolysis box. Add 0.2% of the total mass of sweet potatoes with compound enzyme solution (pectinase: α-amylase = 2:1, mass ratio). Spray evenly and then seal for enzymatic hydrolysis for 30 minutes, stirring once every 10 minutes to ensure complete enzymatic hydrolysis. After enzymatic hydrolysis, 8% of the total mass of sweet potato puree was added to a compound fruit and vegetable puree (hawthorn puree: strawberry puree: pumpkin puree = 2:1:1, mass ratio; the fruit and vegetable puree was sieved through an 80-mesh sieve beforehand to remove coarse fiber), and then 0.3% of a flavor precursor mixture (L-glutamine: anhydrous glucose = 1:1.5, mass ratio). The mixture was then transferred to a high-speed shearing and blending machine and sheared and stirred at 8000 r / min for 10 min. After passing through a 100-mesh sieve, a smooth, particle-free compound sweet potato puree was obtained. Targeted enzymatic hydrolysis degrades pectin and amylopectin in the cell walls of sweet potatoes, promotes the release of flavor precursor substances, weakens the earthy taste of potatoes, and enhances the natural sweetness. Sieve filtration optimizes the fineness of the sweet potato puree and improves the palatability of the product.

[0033] Microfluidic layering molding was performed by uniformly coating the inner wall of the microfluidic layering molding mold with food-grade emulsified silicone oil and activating the mold temperature control system to maintain a temperature of 25°C. First, composite potato puree was injected into the mold as a base layer at a controlled flow rate of 0.5 L / min, set for 1 minute, and the base thickness was controlled at 10 mm. Next, a composite fruit and vegetable interlayer (consistent with the fruit and vegetable puree components in section 3.3) was injected through the mold's secondary channel at a flow rate of 0.1 L / min, set for 30 seconds, and the interlayer thickness was 1 mm. Finally, a probiotic microcapsule layer was injected through the microchannel at a flow rate of 0.05 L / min, set for 1 minute, and the microcapsule layer thickness was 0.5 mm. The mold was closed and compacted for 2 minutes, resulting in a regular composite blank with dimensions of 100 mm long, 50 mm wide, and 11.5 mm high, without any delamination, peeling, or leakage. Precise layering and thickness control ensured the zonal distribution of nutrients, preventing direct contact between probiotics and potato puree and preventing inactivation, thus preserving the activity of functional components and improving the product's structural stability and visual appeal.

[0034] Vacuum precooling and cutting / shaping: The composite blank is transferred to a vacuum precooling machine, set to a precooling temperature of 2℃ and a vacuum degree of 0.08MPa, and precooled for 15 minutes to quickly lower the center temperature of the blank to below 4℃, inhibiting endogenous enzyme activity and microbial growth. After precooling, a CNC cutting machine is used to cut the blank into cubes with a cutting blade temperature controlled at 10℃, measuring 25mm in length, 25mm in width, and 11.5mm in height. The weight of each cube is precisely controlled to 25±0.5g. Scrap and broken pieces are removed to ensure the finished product has a uniform shape. Low-temperature precooling blocks enzymatic browning and reduces the oxidative degradation of nutrients, while low-temperature cutting prevents the cake from deforming, improving the yield rate of the finished product.

[0035] Modified atmosphere packaging and warehousing: Shaped potato cakes are placed into PLA packaging trays, five cakes per tray, and fed into a modified atmosphere packaging machine. After vacuum sealing, a mixed gas with a ratio of N2:CO2:O2 = 60:35:5 is filled in, controlling the residual oxygen level inside the packaging to ≤1.5%. The heat-sealing temperature is 130℃, and the heat-sealing time is 2 seconds, ensuring a tight seal without leakage. The packaged products are stored in a 4℃ constant temperature cold storage. Ventilation gaps are left during packing to prevent deformation due to compression. The modified atmosphere system inhibits the growth of aerobic microorganisms, delays starch aging and flavor loss, replaces traditional frozen storage, reduces cold chain costs, and extends product shelf life.

[0036] Using potato cakes prepared using traditional freezing processes as the control group, and the product in this example as the experimental group, various indicators were tested under the same storage conditions, and the results are as follows:

[0037] Hardness (g) 420±15 580±20 Texture analyzer P / 50 probe, testing speed 1mm / s elasticity 0.85±0.02 0.72±0.03 Texture analyzer cyclic compression test Flavor rating (out of 10) 8.7±0.3 7.2±0.4 Blind test conducted by 10 professional sensory evaluators Color after 7 days of storage at 4℃ Bright color, no browning Slight browning and darkening of the surface Visual observation method shelf life 28d 14 days (frozen at -18℃) <![CDATA[Total number of colonies ≤ 10 4 CFU / g as the limit]]>

[0038] The product in this embodiment has significantly reduced hardness and increased elasticity, indicating a softer and more palatable texture; the flavor score has increased by 20.8%, and the shelf life has doubled, verifying the effectiveness of the process optimization.

[0039] The retention rates of vitamin C and dietary fiber, as well as the number of live probiotics, were tested using national standard methods. The results are as follows:

[0040] Vitamin C 82.3% 65.1% Ultraviolet spectrophotometry Dietary fiber 91.2% 78.5% National Standard GB5009.88-2014 Probiotic live bacteria count <![CDATA[≥10 7 CFU / g]]> <![CDATA[≤10 5 CFU / g]]> Plate counting method

[0041] Enzymatic hydrolysis and modified atmosphere packaging processes can reduce the oxidation and degradation of nutrients, significantly improve nutrient retention efficiency, and optimize the nutritional value of products.

[0042] This embodiment uses a combination of directional enzymatic hydrolysis, layered molding, and modified atmosphere packaging to prepare a compound fruit and vegetable nutritious potato cake product with a soft texture, rich flavor, and high nutrient retention rate. This solves the problems of texture aging and flavor loss caused by traditional processes that rely on freezing storage, and promotes the ready-to-eat and industrial application of the product.

[0043] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method of preparing a composite fruit and vegetable nutritional potato cake product, characterized by, Specifically, the following steps are included: S1. Sweet potato pretreatment Wash the fresh sweet potatoes and steam them at 95-105℃ for 20-30 minutes. Then quickly cool them to -18~-22℃ and freeze them for 2-4 hours. After thawing, peel them. S2. Enzymatic hydrolysis and modification to produce mud. Place the peeled sweet potatoes in a constant temperature environment of 32-38℃, add 0.1%-0.3% of pectinase and amylase compound enzyme solution by weight of sweet potatoes, and enzymatically hydrolyze for 20-40 minutes. Then add 5%-10% of compound fruit and vegetable puree and 0.2%-0.5% of flavor precursor mixture by weight of sweet potato puree, and stir at high speed to make uniform sweet potato puree. S3. Layered molding Using the mashed potato as a base layer, a composite fruit and vegetable interlayer and a nutrient microcapsule layer are sequentially injected through a microfluidic mold, with the thickness of each layer controlled to be 0.5-2mm, to form a composite structure blank. S4. Freshness-locking treatment The shaped blank is pre-cooled in a vacuum at 0-4℃ for 10-20 minutes, then cut into pieces, weighed, packaged in modified atmosphere packaging, and finally stored in a refrigerator at 2-6℃.

2. A process for the preparation of a composite fruit and vegetable nutritional potato cake product as claimed in claim 1, characterized in that: In S1, the steamed sweet potatoes are cooled to below 60℃ before being frozen, with the freezing rate controlled at 1-2℃ / min.

3. A process for the preparation of a composite fruit and vegetable nutritional potato cake product as claimed in claim 1, wherein: In S2, the mass ratio of pectinase to amylase is 1:1-2:1, and the flavor precursor mixture is a mixture of glutamine and glucose in a mass ratio of 1:1-1:

2.

4. A process for the preparation of a composite fruit and vegetable nutritional potato cake product as claimed in claim 1, wherein: In S2, the compound fruit and vegetable puree is made by mixing hawthorn puree, strawberry puree and pumpkin puree in a mass ratio of 2:1:

1.

5. A process for the preparation of a composite fruit and vegetable nutritional potato cake product as claimed in claim 1, wherein: In S3, the nutrient microcapsule layer is an edible starch microcapsule containing probiotics or dietary fiber, with a microcapsule particle size of 50-200μm.

6. A process for the preparation of a composite fruit and vegetable nutritional potato cake product as claimed in claim 1, wherein: In S4, the modified atmosphere packaging is filled with a mixture of N2, CO2, and O2 in a volume ratio of 60:35:5, and the residual oxygen content in the packaging is ≤2%.

7. A process for the preparation of a composite fruit and vegetable nutritional potato cake product as claimed in claim 1, wherein: In S4, the weight of a single piece of potato cake after cutting is 20-30g, and the shape is cuboid or cube.

8. A compound fruit and vegetable nutritious potato cake product, comprising the product, characterized in that: The product has a multi-layered composite structure, with a sweet potato puree base on the surface and a composite fruit and vegetable layer and a nutrient microcapsule layer sandwiched in the middle.