Green-peel pepper and processing method thereof

Abstract

The invention relates to a green-skin pepper processing method, which relates to the technical field of plant color protection, and comprises the steps of fixation, two-phase color protection treatment and gradient drying. A cold color protection solution containing phytic acid, ascorbic acid and 200nm magnesium gluconate large particles is combined with a hot color protection solution containing tetrasodium iminodisuccinate, glutathione and 20nm magnesium gluconate small particles, and a cold and hot phase separation design is adopted: the 200nm large particles are embedded into an epidermal wax coat at 4 DEG C to block oxygen; the 20nm small particles are used for supplementing phaeophytin cavities in a targeted manner through quantum tunneling at 40 DEG C, and Mg < 2 + >-porphyrin ring regeneration is completed; and four-stage gradient drying (pre-curing at 60 DEG C, high-temperature locking at 65 DEG C, intermediate-temperature chain building at 60 DEG C and low-temperature balancing at 55 DEG C) gives consideration to dehydration efficiency and active ingredient retention. The problems of serious browning and loss of effective components in traditional processing are solved.

Description

Technical Field

[0001] This invention relates to the field of plant color-protecting agents, and more particularly to a green-skinned pepper and its processing method. Background Technology

[0002] black pepper( Pipernigrum L. Pepper is one of the world's most important spice crops, often called the "King of Spices." Originally from India and Vietnam, pepper is widely cultivated in Wenchang, Wanning, and Qionghai in Hainan Province, my country, and is a significant economic crop. Currently, commercially available processed pepper products include black pepper, white pepper, and green pepper. Black pepper processing involves significant nutrient loss; white pepper processing primarily uses a water-fermentation method, which easily leads to excessive levels of E. coli and a strong putrid odor. Both differ greatly from fresh pepper in their vibrant green color, glossy appearance, and spicy aroma.

[0003] Compared to black and white pepper, green pepper has a vibrant green color, a fresh and natural aroma with a slightly fruity flavor, and a lower spiciness, thus avoiding the volatilization of many flavor compounds and microbial contamination during processing. Currently, developed green pepper products include pickled green pepper and green pepper sauce, but freeze-dried green pepper produced using vacuum freeze-drying technology retains the color and shape of fresh pepper to the greatest extent, making it a promising primary processed product. However, this processing method is energy-intensive, has a long production cycle, requires a large initial investment, and incurs high maintenance costs.

[0004] Existing color-protecting agents cannot protect the color on both the surface and depth, browning spreads during drying, and they cannot be used to treat peppers at different stages of ripeness.

[0005] To address the various problems in the current processing and production of dried green pepper, developing a green pepper processing technology with lower energy consumption, lower maintenance costs, higher output, and better product quality will help reduce the production cost of green pepper, break the market monopoly of black and white pepper, and increase the market competitiveness of green pepper. Summary of the Invention

[0006] This application provides a green pepper and its processing method, which solves the problem of insufficient color protection technology for green pepper in the prior art and achieves better color retention and protection.

[0007] This application provides a green-skinned pepper and its processing method, including: (1) Use fresh green peppers with a maturity of 6-8 as raw materials, remove the stems, thresh the seeds and wash them; (2) Blanch the peppercorns at 100℃ for 5 minutes; (3) After fixation, the pepper is subjected to cold color protection treatment, hot color protection treatment and lemon acid cleaning in sequence. The cold color protection treatment conditions are: 30 min of ice bath ultrasonic treatment in a cold color protection liquid with a material-liquid ratio of 1:4, and 12 min of static standing after draining; the hot color protection treatment conditions are: 18 min of 180W ultrasonic treatment in a hot color protection liquid with a material-liquid ratio of 1:4, and then spraying cleaning with a 0.5% lemon acid solution at 25°C, and centrifugal draining; (4) The drained pepper is subjected to four-stage gradient drying: 0.5 h of treatment at 60°C and a wind speed of 2.5 m / s; 1.0 h of treatment at 65°C and a wind speed of 3.5 m / s; 4.5 h of treatment at 60°C and a wind speed of 2.0 m / s; and 2.0 h of treatment at 55°C and a wind speed of 1.0 m / s, until the moisture content is less than 10%.

[0008] Further, the cold color protection liquid comprises: 0.10 mg / ml phytic acid, 0.05 mg / ml ascorbic acid and 0.25 mg / ml large particles of magnesium gluconate with a particle size of 200 nm.

[0009] Further, the hot color protection liquid comprises: 0.18 mg / ml tetrasodium iminodisuccinate, 0.50 mg / ml glutathione, 0.25 mg / ml small particles of magnesium gluconate with a particle size of 20 nm and 0.05 mg / ml ascorbic acid.

[0010] Further, the preparation of the cold color protection liquid comprises: adding phytic acid and ascorbic acid in pure water at 4°C, stirring at 300 rpm for 15 min under light-proof conditions; and adding large particles of magnesium gluconate with a particle size of 200 nm, and ultrasonic dispersing for 5 min at 100W under 4°C.

[0011] Further, the preparation of the hot color protection liquid comprises: adding tetrasodium iminodisuccinate and glutathione in pure water at 40°C, stirring under nitrogen protection; adding small particles of magnesium gluconate with a particle size of 20 nm and ascorbic acid, and ultrasonic dispersing for 10 min at 40 kHz.

[0012] A green-skinned pepper is prepared by the processing method of the green-skinned pepper.

[0013] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages: Firstly, the cold color protection liquid containing phytic acid, ascorbic acid and large particles of magnesium gluconate with a particle size of 200 nm, in combination with the hot color protection liquid containing tetrasodium iminodisuccinate, glutathione and small particles of magnesium gluconate with a particle size of 20 nm, through cold-hot phase separation design: the 200 nm large particles are embedded in the epidermal wax layer to block oxygen at 4°C, and the 20 nm small particles target the supplement of the cavity of the de-magnesium chlorophyll through quantum tunneling at 40°C, to complete the Mg 2+ - porphyrin ring regeneration.

[0014] Secondly, the four-stage gradient drying (60℃ pre-curing → 65℃ high-temperature locking → 60℃ medium-temperature chain building → 55℃ low-temperature balancing) is adopted, which takes into account the dehydration efficiency and active ingredient retention. The method makes the apparent color L * ≥55、a * ≤-6.20, the yield of essential oil is 2.0-3.2%, and the yield of piperine is 3.5-4.5%, which solves the problems of serious browning and loss of effective components in traditional processing. BRIEF DESCRIPTION OF DRAWINGS

[0015] Figure 1 Picture of the pepper processed by using the optimal color protection agent according to the present application; Figure 2 Picture of the pepper processed without using the color protection agent according to the present application. DETAILED DESCRIPTION

[0016] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application; the use herein of the terms "and / or" includes a set of one or more associated listed items.

[0017] A processing method of green skin pepper, the specific steps comprising: S1, taking fresh green skin pepper with maturity of 6-8 as raw material, removing stem and dehulling the green skin pepper, and washing at least twice; S2, carrying out fixation treatment on the washed green skin pepper at 100℃ for 5min; S3, quickly transferring the fixed pepper into a color protection agent, and carrying out ice bath ultrasonic treatment for 30min, then washing and draining; The pepper is immersed in cold color protection liquid (material liquid ratio 1:4) and placed for 12min, then drained and transferred into hot color protection liquid (material liquid ratio 1:4), and ultrasonic treatment is carried out at 180W for 18min, then 0.5% citric acid solution is sprayed for cleaning once, and centrifugal draining is carried out; The preparation method of the cold color protection liquid is as follows: 0.10mg / ml phytic acid and 0.05mg / ml ascorbic acid are added into 4℃ pure water, and stirring is carried out at 300rpm for 15min (avoiding light); 200nm magnesium gluconate large particles (0.25mg / ml) are added, and ultrasonic dispersion is carried out at 4℃ (100W, 5min); Heat color protection solution preparation: 40℃ pure water is added with 0.18mg / ml tetrasodium iminodisuccinate, 0.50mg / ml glutathione, nitrogen protection stirring (anti-oxidation); 20nm magnesium gluconate small particles (0.25mg / ml), 0.05mg / ml ascorbic acid, 40kHz ultrasonic 10 minutes; S4, the green skin pepper after draining is dried to obtain green skin pepper particles; drying is divided into four stages, first at 60℃, 2.5m / s, pre-solidification for 0.5h, then at 65℃, 3.5m / s, high temperature locking for 1.0h, then at 60℃, 2.0m / s, medium temperature chain building for 4.5h, finally at 55℃, 1.0m / s, low temperature balancing for 2.0h, the moisture content of pepper is less than 10%.

[0018] The technical solutions in the embodiments of the present application have at least the following technical effects or advantages: Tetrasodium iminodisuccinate is an electronic superconductor medium, the lone pair of electrons of tertiary nitrogen atom (N + ) builds a low-resistance channel, and the electrons provided by glutathione are transmitted to the chlorophyll defect site; the positively charged nitrogen atom repels negatively charged phytic acid, eliminates the competitive chelation of magnesium ions in magnesium gluconate, and removes free radicals; After the magnesium of chlorophyll is removed, a cavity is formed in the center of the porphyrin ring, the positive charge decreases, and the ketone group and imine group at the edge of the cavity can capture magnesium ions. Magnesium ions are partially dissociated in an acidic environment, and are attracted by the local negative electric field of the cavity of the demetallized chlorophyll, and the coordination bond is reorganized. The beta-hydroxyl group of gluconic acid provides a hydrogen bond to stabilize the transition state, reduce the activation energy, and regenerate chlorophyll, so that the green color is preserved. In addition to its own function, phytic acid can also preferentially chelate iron ions and copper ions to leave a channel for magnesium ions, inhibit oxidation and protect the regenerated green color. Glutathione provides electrons to the magnesium-free chlorophyll cation free radical, making it more easily attract magnesium ions; And because the degree of green content in pepper leaves is different, the more mature the green content is, the lower the cell permeability is, so that magnesium ions will be preferentially released in the low green area. After the green color is regenerated, the negative electric field of the porphyrin ring weakens, and the remaining magnesium ions are recaptured by gluconic acid to avoid excessive deposition; Tetrasodium iminodisuccinate acts as a "Y-shaped molecular clamp", one end locks phytic acid through nitrogen atoms, and the other end repels gluconic acid through carboxyl groups, forcing magnesium gluconate to approach chlorophyll in a specific direction. The negative electric field of its carboxyl group accelerates the magnesium ions to shoot at the demetallized cavity of chlorophyll; Large particle magnesium gluconate shrinks in the lattice of cold phase at 4℃, the surface hydroxyl density is low, and the hydrophobicity is enhanced. When impacted by high wind speed (3.5m / s), the large particles are embedded in the cracks of the cuticle wax layer, forming physical anchor points, blocking the oxygen channel and resisting drying stress.

[0019] Due to the quantum confinement effect, small-particle magnesium gluconate exhibits a high concentration of surface defect sites, acting as a springboard for electron transitions. These sites are distributed along anchor points, and their diffusion coefficient is greatly enhanced in the 40°C hot phase. Through quantum tunneling, they penetrate the cell membrane and target the magnesia-free chlorophyll cavity, completing the Mg transition. 2+ -Porphyrin ring coordination regeneration; Experimental verification was conducted on the above embodiments, including an apparent color experiment (the apparent color of the pepper pericarp was determined using color parameters). L * , a * and b * The value is used to explain, among which L * : Indicates the brightness of a color; a positive number indicates a lighter shade, and a negative number indicates a darker shade. a * : Represents the red-green value; a positive number indicates a reddish tint, and a negative number indicates a greenish tint. b * : Indicates the yellow-blue value, positive numbers indicate a yellowish tint, negative numbers indicate a bluish tint; Pepper essential oil determination (determined according to the method specified in GB / T17527-2009 "Determination of Pepper Essential Oil Content"); Piperine determination (determined according to the method specified in GB / T17528-2009 "Determination of Piperine Content by High Performance Liquid Chromatography"); Apparent color experiment: The apparent color of pepper pericarp was measured using a portable colorimeter (WSC-1B) to determine the apparent color parameter L of pepper pericarp. * a * and b * Since the goal of this invention is to characterize the overall color of the pepper sample, the pepper particles were all intact and not crushed when measuring the sample color. The experiment included a comparison between ultrasonic treatment and soaking treatment, and a comparison between single components and overall components. The experimental groups and results are shown in Table 1. Table 1. Results of the apparent color experiment

[0020]

[0021]

[0022]

[0023] Experiment 34 was selected as the optimal color-protecting agent to verify its effect on piperine and pepper essential oil. Determination of pepper essential oil: The essential oil content of green peppercorns was determined according to the method specified in GB / T17527-2009 "Determination of Pepper Essential Oil Content". Pepper oil was extracted by distillation. 15g of green peppercorn powder sample (accurate to 0.001g) passing through a 40-mesh sieve was weighed, and 400mL of distilled water was added. The mixture was slowly distilled for 4 hours. The distillate was collected in a graduated receiving tube. Water and oil separated in the collecting tube, and the volume of pepper oil was read, allowing for the calculation of the pepper oil yield.

[0024] The yield of pepper essential oil obtained was 2.0%-3.2% (mL / g), while the yield of essential oil from fresh green pepper under the same conditions was 1.8%-3.1%. Determination of piperine: The piperine content was determined according to the method specified in GB / T17528-2009 "Determination of Piperine Content by High Performance Liquid Chromatography". 0.2-0.5 g of green pepper powder sample was weighed, and 50 mL of 95% ethanol was added for extraction under reflux for 3 hours. The extract was filtered and diluted to 100 mL. 1 mL of the filtrate was diluted to 25 mL with 95% ethanol, and the sample was filtered through a 0.45 μm filter membrane. Quantitative analysis was then performed using HPLC, and the content was calculated using the external standard method. The yield of piperine was between 3.5% and 4.5% (g / g); under the same conditions, the yield of piperine from fresh green pepper was 3.8%-7.1%.

[0025] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A green-skinned pepper and its processing method, characterized in that, include: (1) Use fresh green peppers with a maturity of 6-8 as raw materials, remove the stems, thresh the seeds and wash them; (2) Blanch the peppercorns at 100℃ for 5 minutes; (3) After blanching, the peppers were subjected to cold color protection treatment, hot color protection treatment and citric acid washing in sequence. The cold color protection treatment conditions were: ultrasonic in ice bath for 30 minutes in cold color protection solution with a material-to-liquid ratio of 1:4, drained and left to stand for 12 minutes; the hot color protection treatment conditions were: ultrasonic in hot color protection solution with a material-to-liquid ratio of 1:4 at 180W for 18 minutes, then sprayed and washed with 0.5% citric acid solution at 25℃, centrifuged and drained. (4) The drained peppers were dried in four stages: the first stage was 60℃ and 2.5m / s for 0.5h; the second stage was 65℃ and 3.5m / s for 1.0h; the third stage was 60℃ and 2.0m / s for 4.5h; and the fourth stage was 55℃ and 1.0m / s for 2.0h, until the moisture content was <10%.

2. The processing method of green pepper as described in claim 1, characterized in that, The cold color protection solution contains: 0.10 mg / ml phytic acid, 0.05 mg / ml ascorbic acid, and 0.25 mg / ml magnesium gluconate particles with a particle size of 200 nm.

3. The processing method of green pepper as described in claim 1, characterized in that, The heat-protecting solution contains: 0.18 mg / ml tetrasodium iminodisuccinate, 0.50 mg / ml glutathione, 0.25 mg / ml magnesium gluconate particles with a particle size of 20 nm, and 0.05 mg / ml ascorbic acid.

4. The processing method of green pepper as described in claim 2, characterized in that, The preparation of cold protective liquid includes: Phytic acid and ascorbic acid were added to purified water at 4℃ and stirred at 300 rpm for 15 min under light-protected conditions; 200 nm magnesium gluconate particles were added and ultrasonically dispersed at 100 W for 5 min at 4℃.

5. A processing method for green pepper as described in claim 3, characterized in that, The preparation of the heat-protecting color solution includes: Tetrasodium iminodisuccinate and glutathione were added to purified water at 40℃ and stirred under nitrogen protection; 20nm magnesium gluconate particles and ascorbic acid were added and sonicated at 40kHz for 10min.

6. A green-skinned pepper, characterized in that, It is prepared by the processing method of green pepper as described in any one of claims 1-5.

Images