阅读说明：本技术 一种提高鲜湿米线货架期品质的方法 (Method for improving shelf life quality of fresh wet rice noodles ) 是由 成玉梁 吴培玉 徐琳 李天宇 刘圣楠 陈建男 李培珍 郭亚辉 谢云飞 姚卫蓉 钱 于 2020-11-12 设计创作，主要内容包括：本发明公开了一种提高鲜湿米线货架期品质的方法,属于食品加工技术领域。本发明所述的提高鲜湿米线货架期品质的方法,包括如下步骤：选米、清洗去杂、浸泡磨粉、混料、调节水分、预蒸、挤压成型、冷浸、混油、包装,得到成品鲜湿米线；其中混料是将米粉、玉米淀粉、抗坏血酸混合均匀,得到混合原料；其中抗坏血酸的用量是米粉和玉米淀粉总质量的1～3％；混油是在米线中加入茶叶籽油,充分混合拌匀,米线和茶叶籽油的质量比为100:1～100:6。本发明通过加入茶叶籽油,减少米线的水分挥发损失,抑制直链淀粉的溶出,从而延缓支链淀粉老化,提高鲜湿米线货架期内的品质。(The invention discloses a method for improving the shelf life quality of fresh wet rice noodles, and belongs to the technical field of food processing. The method for improving the shelf life quality of the fresh wet rice noodles comprises the following steps: selecting rice, cleaning, removing impurities, soaking, grinding, mixing, adjusting water content, pre-steaming, extrusion molding, cold soaking, mixing with oil, and packaging to obtain fresh wet rice noodle; wherein the mixing material is prepared by uniformly mixing rice flour, corn starch and ascorbic acid to obtain a mixed raw material; wherein the dosage of the ascorbic acid is 1-3% of the total mass of the rice flour and the corn starch; the mixed oil is prepared by adding tea seed oil into rice noodles, fully mixing and uniformly stirring, wherein the mass ratio of the rice noodles to the tea seed oil is 100: 1-100: 6. According to the invention, by adding the tea seed oil, the water volatilization loss of the rice noodles is reduced, and the dissolution of amylose is inhibited, so that the aging of amylopectin is delayed, and the quality of the fresh wet rice noodles in the shelf life is improved.)

1. A method for improving the shelf life quality of fresh wet rice noodles is characterized by comprising the following steps:

(1) selecting rice;

(2) cleaning and removing impurities;

(3) soaking and grinding to obtain rice flour;

(4) mixing materials: uniformly mixing rice flour, corn starch and ascorbic acid to obtain a mixed raw material; wherein the dosage of the ascorbic acid is 1-3% of the total mass of the rice flour and the corn starch;

(5) adjusting the moisture content;

(6) pre-steaming;

(7) extrusion molding;

(8) cold soaking and draining;

(9) oil mixing: adding tea seed oil into the rice noodles obtained in the step (8), and uniformly mixing; wherein the mass ratio of the rice noodles to the tea seed oil is 100: 1-100: 6;

(10) and packaging to obtain the finished product of the fresh wet rice noodles.

2. The method according to claim 1, wherein the mass ratio of the rice flour to the corn starch in the mixed material in the step (4) is 1: 4-4: 1.

3. The method according to claim 1 or 2, characterized in that the steeping milling in step (3) is in particular: and (3) soaking the rice cleaned in the step (2) in water at a rice-water mass ratio of 1: 1-1: 3 for 3-6 hours, draining water from the soaked rice, and grinding the rice by using a grinder to obtain the rice flour with the particle fineness of 100-200 meshes.

4. The method according to any one of claims 1 to 3, wherein the water content of the mixed raw material in the step (4) is adjusted to 40 to 60% in the step (5), and the water content is balanced for 1 to 3 hours.

5. The method according to any one of claims 1 to 4, wherein the temperature of the pre-steaming in the step (6) is 90 to 100 ℃ and the time is 40 to 90 min.

6. The method according to any one of claims 1 to 5, wherein the extrusion molding in step (7) is specifically: and (3) extruding the material pre-steamed in the step (6) into a round bar shape by adopting a single-screw self-cooked extruder, wherein the rotating speed of the screw is 100rpm, the temperature of the inner wall of the cylinder is 80-110 ℃, and the diameter of a sieve pore is 1.5-2.0 mm.

7. The method according to any one of claims 1 to 6, wherein the specific parameters of the cold leaching in the step (8) are as follows: and (4) soaking the extruded rice noodles in the step (7) in water at the temperature of 5-15 ℃ for 0.5-3 min.

8. The method according to any one of claims 1 to 7, wherein the method for improving the shelf life quality of fresh wet rice noodles further comprises sterilization.

9. The method of claim 8, wherein the sterilization method is: and (4) sterilizing by adopting a pasteurization tank, wherein the sterilization temperature is 80-95 ℃, and the sterilization time is 30-40 min.

10. Fresh wet rice noodles prepared by the method of any one of claims 1 to 9.

Technical Field

The invention relates to a method for improving the shelf life quality of fresh wet rice noodles, and belongs to the technical field of food processing.

Background

The fresh wet rice noodles are food with good taste and flavor, and belong to deep-processed rice products. The quality problems of rice noodles such as loss of elasticity, easy breakage, poor taste and the like are caused by slow aging of starch in the rice noodles in shelf life, and the shelf life of fresh wet rice noodles is seriously shortened.

The fresh wet rice noodle products on the market at present have immature technology and process, high water content and high aging degree of rice noodles, so that the quality of the rice noodles is reduced, and the shelf life is short.

Disclosure of Invention

In order to solve at least one of the above problems, the present invention provides a method for improving the shelf life quality of fresh wet rice noodles. The method of the invention can obviously delay the starch aging of the fresh wet rice noodles in the shelf life, and ensure that the product has good quality in the shelf life. Compared with the traditional process, the method has the advantages that the aging of the starch is delayed by adding the ascorbic acid; by adding the tea seed oil, the edible oil with rich nutrition has the tea polyphenol content of 11.5mg/mL, reduces the water volatilization loss of the rice noodles, and inhibits the dissolution of amylose, thereby delaying the aging of amylopectin and finally improving the quality of the fresh wet rice noodles in the shelf life.

The first purpose of the invention is to provide a method for improving the shelf life quality of fresh wet rice noodles, which comprises the following steps:

(1) selecting rice;

(2) cleaning and removing impurities;

(3) soaking and grinding to obtain rice flour;

(4) mixing materials: uniformly mixing rice flour, corn starch and ascorbic acid to obtain a mixed raw material; wherein the dosage of the ascorbic acid is 1-3% of the total mass of the rice flour and the corn starch;

(5) adjusting the moisture content;

(6) pre-steaming;

(7) extrusion molding;

(8) cold soaking and draining;

(9) oil mixing: adding tea seed oil into the rice noodles obtained in the step (8), and uniformly mixing; wherein the mass ratio of the rice noodles to the tea seed oil is 100: 1-100: 6;

(10) and packaging to obtain the finished product of the fresh wet rice noodles.

In one embodiment of the invention, the dosage of the ascorbic acid in the step (1) is 1-1.5% of the total mass of the rice flour and the corn starch; further preferably 1.5%.

In one embodiment of the invention, the mass ratio of the formed rice noodles subjected to cold soaking in the step (9) to the tea seed oil is 100: 1-100: 6; more preferably 100:1 to 100:1.5, and still more preferably 100:1.

In one embodiment of the invention, the mass ratio of the rice flour to the corn starch in the mixed material in the step (4) is 1: 4-4: 1, more preferably 1: 1-2: 3, and still more preferably 1: 1.

In one embodiment of the present invention, the rice selection in step (1) is to select high-quality early indica rice with smooth surface, no plant diseases and insect pests, and no mildew.

In one embodiment of the present invention, the step (2) of washing and removing impurities comprises washing high-quality early long-shaped rice with water, removing impurities such as sand, and draining.

In one embodiment of the present invention, the soaking and milling in step (3) is specifically: and (3) soaking the rice cleaned in the step (2) in water at a rice-water mass ratio of 1: 1-1: 3 for 3-6 hours, draining water from the soaked rice, and grinding the rice by using a grinder to obtain the rice flour with the particle fineness of 100-200 meshes.

In one embodiment of the present invention, in the step (5), the water content of the mixed raw material in the step (4) is adjusted to 40-60%, and the water content is balanced for 1-3 h.

In one embodiment of the invention, the pre-steaming in the step (6) is performed at a temperature of 90-100 ℃ for 40-90 min.

In one embodiment of the present invention, the extrusion molding in the step (7) is specifically: and (3) extruding the material pre-steamed in the step (6) into a round bar shape by adopting a single-screw self-cooked extruder, wherein the rotating speed of the screw is 100rpm, the temperature of the inner wall of the cylinder is 80-110 ℃, and the diameter of a sieve pore is 1.5-2.0 mm.

In one embodiment of the present invention, the specific parameters of the cold leaching in the step (8) are as follows: and (4) soaking the extruded rice noodles in the step (7) in water at the temperature of 5-15 ℃ for 0.5-3 min.

In one embodiment of the present invention, the packaging in step (10) is performed by packaging the rice noodles obtained in step (9) in a retort pouch and sealing the retort pouch.

In one embodiment of the present invention, the method for improving the shelf life quality of fresh wet rice noodles further comprises sterilization.

In one embodiment of the present invention, the sterilization method comprises: and (4) sterilizing by adopting a pasteurization tank, wherein the sterilization temperature is 80-95 ℃, and the sterilization time is 30-40 min.

The second purpose of the invention is the fresh wet rice noodles prepared by the method.

The invention has the beneficial effects that:

(1) the method of the invention adopts the addition of ascorbic acid to delay the starch aging and simultaneously make the rice noodle more nutritious.

(2) According to the fresh wet rice noodles prepared by the method, the tea seed oil is added, so that the water volatilization loss is reduced, and the dissolution of amylose is inhibited, so that the aging of amylopectin is delayed, and the quality of the fresh wet rice noodles in the shelf life is improved.

(3) The fresh wet rice noodles prepared by the method can be eaten after being boiled in boiling water for 5min, and are very convenient.

(4) The breakage rate of the fresh wet rice noodles prepared by the method is below 7 percent, and can reach 4.28 percent at the lowest; the elasticity reaches over 0.836 and can be as high as 0.902; the tensile strength reaches 11.94g/mm²Above, can be up to 14.11g/mm²(ii) a The crystallinity is less than 9.26%.

Drawings

FIG. 1 shows a finished product of fresh and wet rice noodles prepared in example 1 and stored at room temperature for 60 days.

Detailed Description

The following description of the preferred embodiments of the present invention is provided for the purpose of better illustrating the invention and is not intended to limit the invention thereto.

The test method comprises the following steps:

1. the test method of the broken rate of the fresh wet rice noodles and a calculation formula are as follows:

selecting 3 parts of rice noodles with the length of more than 20cm, wherein each part is 150g, completely immersing the rice noodles in boiling water for 5min, filtering out water after immersion, supercooling water for 1min, draining, pouring into an enamel tray, separating rice noodle strips with the length of less than 10cm and rice noodle strips with the length of more than 10cm, weighing respectively, and calculating the strip breakage rate, wherein the specific formula is as follows (1):

in the formula: m₁The mass (g) of the rice-flour noodles with the length less than 10 cm; m₂The mass (g) of the rice-flour noodles with the length exceeding 10cm is obtained.

2. The method for testing the elasticity of the fresh wet rice noodles comprises the following steps:

soaking rice noodle in boiling water for 5min, taking out, placing rice noodle in cooled distilled water, standing for 30s, taking out, draining water on the surface of rice noodle, measuring 1 rice noodle on TA.XT plus physical property tester, selecting TPA mode, setting P/0.5 probe, setting speed before measurement: 5mm/s, test speed: 2mm/s, speed after measurement: 5mm/s, compression 75%, residence time 5s, trigger force: 5g, 5 replicates were run for each sample and the results averaged.

3. The test method and the calculation formula of the tensile strength of the fresh wet rice noodles are as follows:

when the tensile test is carried out, the test is carried out in a physical property analyzer TA.XTPlus, and the rice noodle is wound by 2-3 circles of parallel friction rollers to prevent any sliding. A Measure Force in Tension mode and an A/KIE probe are selected, the stress is 5g, the tensile deformation is 100%, the speed before and after measurement is 5.00mm/s, and the test speed is 1.00 mm/s. Each sample was run in 5 replicates and the results averaged. The specific calculation formula is as follows (2):

4. the method for testing the crystallinity of the fresh wet rice noodles comprises the following steps:

the freeze-dried rice noodles were pulverized and sieved through a 80-mesh sieve, and the sample was allowed to equilibrate for moisture for 24 hours at 4 ℃ before measurement. Using X-ray diffraction analysis, taking a proper amount of sample powder in a round hole of a test board, and compacting by using a glass slide. Scanning is carried out at a scanning frequency of 2 DEG/min, with a step size of 0.02 DEG and from 5 DEG to 40 deg.

The specific calculation formula is as follows (3):

in the formula: DoC-degree of crystallinity, I_cRadiation intensity of crystalline and amorphous phases, I_amorf-radiation intensity in amorphous phase.

5. Microstructure:

the fresh wet rice noodle microstructure was observed using a Scanning Electron Microscope (SEM). Firstly, processing rice noodles by adopting a double-fixation method: fresh wet rice noodle samples were cut into 1cm long pieces, fixed in glutaraldehyde (2.5%) for 2h, and rinsed four times with cold phosphate buffer (0.1mol/L, 4 ℃). The samples were then fixed in osmium tetroxide (1%) for 1.5h, washed four times with cold phosphate buffer (0.1mol/L, 4 ℃), eluted with a series of gradients of ethanol (30%, 50%, 70%, 90% and 100%) for 5min each, and finally stripped of ethanol with isoamyl acetate. After double fixing and critical point drying, gold spraying treatment was performed, and the surface image of the meter line was photographed under an acceleration voltage of 1.0 kV. The magnification is 1200 times.

6. Sensory evaluation:

sensory evaluation of rice noodle quality: the evaluation group consists of 8 persons, the products are respectively graded from 4 aspects of the color, the smell, the tissue form and the taste of the products according to the grading standard, the products cannot be discussed mutually, and the evaluation results are the average values of 8 groups. Specific evaluation criteria are shown in table 1:

TABLE 1 organoleptic scoring criteria for fresh and wet rice noodles quality

Example 1

A method for improving the shelf life quality of fresh wet rice noodles comprises the following steps:

(1) selecting rice: selecting 50kg of high-quality early long-shaped rice with smooth surface, no diseases and insect pests and no mildew;

(2) cleaning and impurity removal: washing high-quality early long-grained nonglutinous rice, removing impurities such as sand and stones, and draining;

(3) soaking and grinding: soaking high-quality early long-shaped rice in water for 4 hours according to the rice-water ratio of 1:2, and draining the water of the soaked high-quality early long-shaped rice; then grinding by a grinder, and controlling the particle fineness to be 100 meshes to obtain rice flour;

(4) mixing materials: uniformly mixing 50kg of rice flour, 50kg of corn starch and 1.5kg of ascorbic acid to obtain a mixed raw material;

(5) adjusting the moisture content: regulating the water content of the mixed raw materials to 40% and balancing the water content for 1 h;

(6) pre-steaming: putting the material with balanced water into a steam box for steaming for 50min at the temperature of 100 ℃ for pre-gelatinization;

(7) extrusion molding: extruding the pre-steamed material into a round bar shape by adopting a single-screw self-cooked extruder, wherein the rotating speed of a screw is 100rpm, the temperature of the inner wall of a cylinder body is 90 ℃, and the diameter of a sieve pore is 2.0 mm; obtaining a formed rice noodle;

(8) cold soaking: soaking the formed rice noodles in water at 10 ℃ for 30s, and draining;

(9) oil mixing: adding 2g of tea seed oil into 200g of the rice noodles in the step (8), and fully mixing and stirring uniformly;

(10) packaging: bagging and sealing;

(11) and (3) sterilization: sterilizing at 90 deg.C for 30 min; cooling to room temperature (about 25 deg.C) to obtain fresh wet rice noodle product.

FIG. 1 shows the finished product of the fresh wet rice noodles of example 1 stored at room temperature for 60 days, from which it can be seen that the prepared rice noodles have smooth surface, are milky white, glossy and have no obvious broken noodles.

Example 2

The amount of ascorbic acid used in step (4) of example 1 was adjusted as shown in Table 2, and the balance was kept the same as in example 1, to obtain a finished product of fresh wet rice noodles.

The fresh wet rice noodles stored at room temperature for 60 days of examples 1 and 2 were subjected to the performance test, and the test results are shown in the following tables 2 and 3:

table 2 test results for examples 1 and 2

Table 3 sensory test results of examples 1 and 2

Example 3

The amount of tea seed oil used in step (9) of example 1 was adjusted as shown in Table 4, and the balance was maintained in the same manner as in example 1 to obtain a finished product of fresh wet rice noodle.

The fresh wet rice noodle products of example 1 and example 3, which were stored at normal temperature for 60 days, were subjected to the performance test, and the test results are shown in the following tables 4 and 5:

table 4 test results for examples 1 and 3

Table 5 sensory test results of examples 1 and 3

Tea seed oil (g)	Appearance of the product	Smell(s)	Taste of the product	Total score
					2 (example 1)	28	27	37	92
3	26	28	33	87
					12	12	19	15	46
0.5	13	17	23	53
					20	18	7	5	30

Example 4

The amount of added corn starch in step (4) of example 1 was adjusted as shown in Table 6, and the balance was maintained as in example 1 to obtain a finished product of fresh wet rice noodles.

The fresh wet rice noodle products of example 1 and example 4, which were stored at room temperature for 60 days, were subjected to the performance test, and the test results are shown in the following tables 6 and 7:

table 6 test results of example 1 and example 4

Table 7 sensory test results of examples 1 and 4

Rice flour-corn starch	Appearance of the product	Smell(s)	Taste of the product	Total score
					1:1	28	27	37	92
2:3	27	28	32	85
					10:1	25	29	14	68
5:1	14	16	26	56
					1:5	19	9	19	47

Comparative example 1

The ascorbic acid in the step (4) is omitted, and the rest is kept the same as the embodiment 1, so that the finished product of the fresh wet rice noodles is obtained.

Comparative example 2

The tea seed oil in the step (9) is omitted, and the rest is kept consistent with the embodiment 1, so that the finished product of the fresh wet rice noodle is obtained.

Comparative example 3

The corn starch in the step (4) is omitted, and the rest is kept the same as the example 1, so that the finished product of the fresh wet rice noodles is obtained.

Comparative example 4

And (5) adjusting the ascorbic acid in the step (4) to be sodium lactate, and keeping the balance of the ascorbic acid to be consistent with that in the example 1 to obtain a finished product of the fresh wet rice noodles.

Comparative example 5

And (4) adjusting the tea seed oil in the step (9) to be rapeseed oil, and keeping the balance consistent with that in the example 1 to obtain a finished product of the fresh wet rice noodle.

Comparative example 6

The corn starch in example 1 was replaced with wheat starch, and the rest was the same as in example 1, to obtain a finished fresh wet rice noodle.

The fresh wet rice noodle products of comparative examples 1 to 6, which were stored at normal temperature for 60 days, were subjected to the performance tests, and the test results are shown in tables 8 and 9 below:

TABLE 8 results of the Performance test of comparative examples 1 to 6

TABLE 9 sensory test results of comparative examples 1 to 6

Comparative example	Appearance of the product	Smell(s)	Taste of the product	Total score
					1	23	26	27	76
2	28	25	24	77
					3	10	29	19	58
4	23	26	27	75
					5	20	17	26	63
6	7	12	13	32

Although the present invention has been described with reference to the preferred embodiments, it should be understood that various changes and modifications can be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.