CN115517340A

CN115517340A - Spicy instant bean curd sticks and preparation method thereof

Info

Publication number: CN115517340A
Application number: CN202211264974.1A
Authority: CN
Inventors: 冯紫艳; 王丽娜; 李培睿
Original assignee: Xuchang University
Current assignee: Xuchang University
Priority date: 2022-10-17
Filing date: 2022-10-17
Publication date: 2022-12-27

Abstract

The invention relates to the technical field of food, in particular to spicy instant dried beancurd sticks and a preparation method thereof. The method specifically comprises the following steps: dried beancurd sticks and oil; the oil material is prepared from the following components in parts by mass: 40.8 to 48.8 parts of oil, 16.6 to 20.6 parts of green onion, 8.6 to 12.6 parts of ginger, 2.0 to 2.4 parts of anise, 1.0 to 1.4 parts of pepper, 2.2 to 2.6 parts of hot pepper, 3.8 to 5.8 parts of sesame, 0.4 to 0.6 part of salt, 2.0 to 2.4 parts of light soy sauce, 1.0 to 1.4 parts of sugar and 12.4 to 16.4 parts of water. The spicy instant dried beancurd sticks prepared by the invention are uniform in color, golden yellow and have certain luster; regular shape, uniform size and no impurities; the smell is normal, and the beancurd sheet has light beancurd stick fragrance and sesame fragrance; the seasoning has the advantages of moderate flavor, moderate spicy taste, moderate aftertaste and moderate greasiness; the tissue state is uniform, and the dried beancurd sticks are not easy to break and chewy.

Description

Spicy instant bean curd sticks and preparation method thereof

Technical Field

The invention relates to the technical field of food, in particular to spicy instant dried beancurd sticks and a preparation method thereof.

Background

A bean curd stick is a vegetarian food with rich nutrition prepared by taking leguminous plant soybeans as raw materials, and generally contains about 50 percent of protein and about 28 percent of fat. Most of the dried bean curd sticks are leaf-shaped or branch-shaped, the surface of the dried bean curd sticks is light yellow in color and can be compared favorably with yellow flowers; smelling the taste, having strong bean fragrance and being refreshing; the whole body is slightly broken. The dried beancurd stick is rich in calcium, phosphorus, iron and thiamine, and the composition of amino acid is close to the normal requirement of human body. The bean sauce is soaked and boiled, the bean fragrance is diffused all around, and the bean sauce can be prepared into various delicious dishes, and is suitable for frying, stir-frying, frying and stewing. When being eaten in a proper amount, the health food can prevent anemia, hyperlipidemia and arteriosclerosis, and has the effects of nourishing the stomach, supplementing calcium, clearing heat, moistening lung, dissolving phlegm, relieving cough and the like. Dried beancurd sticks are one of the famous health-care foods and are called 'meat in vegetable'.

The prefabricated vegetable is a finished product or a semi-finished product which is prepared by taking agricultural, livestock, poultry and aquatic products as raw materials, matching with various auxiliary materials and then preprocessing. With the progress of the times, the pace of life of people is faster and faster. The fast-paced life gradually becomes a normal state, people have stronger and stronger demand for fast food, and the prefabricated vegetables are distinguished from the catering industry. The prepared dishes are mainly classified into three categories, namely ready-to-prepare foods, ready-to-eat foods and ready-to-cook foods. In the eyes of the public consumers, the prepared dishes are still in the concept of instant foods such as semi-finished products, cooking bags, fast foods and the like.

By preparing dishes, the catering industry can become a provider of food content from the producer of food. The method reduces multiple expenses of food transportation, storage, artificial making and the like, and greatly saves the expenditure of the catering industry. Most of the prefabricated vegetable products on the market are meat products, aquatic products and vegetable products. Bean products are fewer, and especially, bean curd sticks have a longer shelf life in a dry state due to the production principle and the structural characteristics of the bean curd sticks, and are sold as dry products. The few instant dried bean curd stick products are mainly divided into two types, namely, the instant cold dishes are not packaged and need to be sold immediately after being made on the same day. Secondly, the packaged finished product is preserved for 15 to 30 days and can be only preserved by refrigeration.

Three types of instant dried beancurd sticks which are well sold in the market are researched and respectively: (1) the seasoning of the instant bean curd sticks stays on the surface, and the aftertaste is slight; (2) the finished bean curd sticks are mixed with a large amount of seasonings, the aftertaste is fragrant, and the bean curd sticks are too heavy in taste and greasy in the early period and not healthy; (3) the dried bean curd sticks are in a marinated package type, and the taste of the dried bean curd sticks penetrates into the dried bean curd sticks after the previous soaking treatment, but the moisture content is too high, and the shelf life is short.

Therefore, how to prepare the dried beancurd sticks into instant prepared vegetables is a problem to be solved urgently by technical personnel in the field so as to solve the technical problem that the instant foods of the dried beancurd sticks are lacked in the prior art.

Disclosure of Invention

The invention aims to provide spicy instant dried beancurd sticks and a preparation method thereof.

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

the invention provides spicy instant dried beancurd sticks, which comprise: dried beancurd sticks and oil; the mass ratio of the dried beancurd sticks to the oil is 20.5-28.5: 9 to 13;

the oil material is prepared from the following components in parts by mass: 40.8 to 48.8 portions of oil, 16.6 to 20.6 portions of scallion, 8.6 to 12.6 portions of ginger, 2.0 to 2.4 portions of anise, 1.0 to 1.4 portions of pepper, 2.2 to 2.6 portions of hot pepper, 3.8 to 5.8 portions of sesame, 0.4 to 0.6 portion of salt, 2.0 to 2.4 portions of light soy sauce, 1.0 to 1.4 portions of sugar and 12.4 to 16.4 portions of water.

Preferably, the dried beancurd sticks are fried dried beancurd sticks; the preparation method of the fried bean curd sticks comprises the following steps: mixing dried beancurd stick, salt, white vinegar and water, soaking, drying and frying.

Preferably, the temperature of the water is 45-55 ℃; the final concentration of the salt is 1.5-2.5 wt%; the final concentration of the white vinegar is 0.5-1.5 vt%; the soaking time is 90-110 min.

Preferably, the water content of the dried bean curd sticks is less than or equal to 48 percent; the frying temperature is 130-150 ℃; the frying time is 25-35 s.

Preferably, the preparation method of the oil material comprises the following steps:

(1) Soaking fructus Anisi Stellati, capsici fructus and fructus Zanthoxyli in water respectively;

(2) Frying the anise and the hot pepper in cold oil, taking the anise and the hot pepper out, frying the pepper and the ginger, adding the scallion, frying, taking the ginger slices, the scallion and the pepper out, stopping heating, adding the sesame, and frying to obtain a material 1;

(3) And (3) mixing the material 1 obtained in the step (2), light soy sauce, sugar, salt and water to obtain the oil material.

Preferably, the frying temperature of the aniseed and the hot pepper in the step (2) is 115-125 ℃, and the frying time is 13-17 min.

Preferably, the frying temperature of the pepper and the ginger in the step (2) is 175-185 ℃, and the frying time is 13-17 min.

Preferably, the frying time of the scallion in the step (2) is 10-14 min.

Preferably, the time for frying the sesame in the step (2) is 4-6 min.

The invention also provides a preparation method of the spicy instant dried beancurd sticks, which is characterized in that the dried beancurd sticks are mixed with oil materials.

Compared with the prior art, the invention has the following beneficial effects:

the spicy instant dried beancurd sticks prepared by the invention are uniform in color, golden yellow and have certain luster; regular shape, uniform size and no impurities; the smell is normal, and the beancurd sheet has light beancurd stick fragrance and sesame fragrance; the seasoning has the advantages of proper flavor, moderate spicy taste, moderate aftertaste and moderate greasiness; the tissue state is uniform, and the dried beancurd sticks are not easy to break and chewy.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is the effect of water temperature on the swelling of dried beancurd sticks;

FIG. 2 is the effect of the addition of salt on the soaking time of dried beancurd sticks;

FIG. 3 is a graph showing the effect of salt addition on wet dried beancurd sticks;

FIG. 4 is a graph showing the effect of white vinegar on the quality of wet-rot bamboo;

FIG. 5 is a graph of the effect of soaking time on wet-rot bamboo texture;

FIG. 6 is a graph of the effect of soaking time on the quality of wet bamboo shoots;

FIG. 7 is a graph showing the effect of frying temperature and time on the quality of dried beancurd sticks;

FIG. 8 is the effect of frying temperature on the stickiness of dried beancurd sticks;

FIG. 9 is the effect of frying temperature on the cohesiveness of dried beancurd sticks;

FIG. 10 is the effect of frying temperature on the elasticity of dried beancurd sticks;

FIG. 11 is the effect of frying temperature on the chewiness of dried beancurd sticks.

Detailed Description

the oil is prepared from the following components in parts by mass: 40.8 to 48.8 parts of oil, 16.6 to 20.6 parts of scallion, 8.6 to 12.6 parts of ginger, 2.0 to 2.4 parts of anise, 1.0 to 1.4 parts of pepper, 2.2 to 2.6 parts of hot pepper, 3.8 to 5.8 parts of sesame, 0.4 to 0.6 part of salt, 2.0 to 2.4 parts of light soy sauce, 1.0 to 1.4 parts of sugar and 12.4 to 16.4 parts of water; preferably, the oil material is prepared from the following components in parts by mass: 41.8 to 47.8 parts of oil, 17.6 to 19.6 parts of green onion, 9.6 to 11.6 parts of ginger, 2.1 to 2.3 parts of anise, 1.1 to 1.3 parts of pepper, 2.3 to 2.5 parts of hot pepper, 4.0 to 5.6 parts of sesame, 0.5 part of salt, 2.1 to 2.3 parts of light soy sauce, 1.1 to 1.3 parts of sugar and 13.4 to 15.4 parts of water; the oil material is further preferably prepared from the following components in parts by mass: 42.8 to 46.8 parts of oil, 18.6 parts of scallion, 10.6 parts of ginger, 2.2 parts of anise, 1.2 parts of pepper, 2.4 parts of hot pepper, 4.4 to 5.2 parts of sesame, 0.5 part of salt, 2.2 parts of light soy sauce, 1.2 parts of sugar and 14.4 parts of water; more preferably, the oil material is prepared from the following components in parts by mass: 44.8 parts of oil, 18.6 parts of green onion, 10.6 parts of ginger, 2.2 parts of anise, 1.2 parts of pepper, 2.4 parts of hot pepper, 4.8 parts of sesame, 0.5 part of salt, 2.2 parts of light soy sauce, 1.2 parts of sugar and 14.4 parts of water.

In the invention, the dried beancurd sticks are fried dried beancurd sticks; the preparation method of the fried bean curd sticks comprises the following steps: mixing dried beancurd stick, salt, white vinegar and water, soaking, drying and frying.

In the invention, the temperature of the water is 45-55 ℃; preferably 47 to 53 ℃; more preferably 49 to 51 ℃; more preferably 50 deg.c.

In the present invention, the final concentration of the salt is 1.5 to 2.5wt%; preferably 1.7 to 2.3wt%; further preferably 1.9 to 2.1wt%; more preferably 2wt%.

In the invention, the final concentration of the white vinegar is 0.5-1.5 vt%; preferably 0.7 to 1.3vt%; more preferably 0.9 to 1.1vt%; more preferably 1vt%.

In the invention, the soaking time is 90-110 min; preferably 94-106 min; further preferably 98 to 102min; more preferably 100min.

In the invention, the water content of the dried bean curd sticks is less than or equal to 48 percent; preferably 40 to 48 percent; more preferably from 42 to 46%; more preferably 44%.

In the invention, the frying temperature is 130-150 ℃; preferably 135 to 145 ℃; further preferably 140 ℃.

In the invention, the frying time is 25-35 s; preferably 27 to 33s; more preferably 29 to 31s; more preferably 30s.

In the invention, the preparation method of the oil material comprises the following steps:

(3) And (3) mixing the material 1 obtained in the step (2), light soy sauce, sugar, salt and water.

In the invention, the frying temperature of the aniseed and the hot pepper in the step (2) is 115-125 ℃; preferably 117 to 123 ℃; further preferably 119 to 121 ℃; more preferably 120 deg.c.

In the invention, the frying time in the step (2) is 13-17 min; preferably 14-16 min; more preferably 15min.

In the invention, the frying temperature of the pepper and the ginger in the step (2) is 175-185 ℃; preferably 177 to 183 ℃; further preferably 179 to 181 ℃; more preferably 180 deg.c.

In the invention, the frying time in the step (2) is 13-17 min; preferably 14-16 min; further preferably 15min.

In the invention, the frying time of the scallion in the step (2) is 10-14 min; preferably 11-13 min; further preferably; more preferably 12min.

In the invention, the frying time of the sesame in the step (2) is 4-6 min; preferably for 5min.

The technical solutions provided by the present invention are described in detail below with reference to examples, but they should not be construed as limiting the scope of the present invention.

Example 1

1. Test materials and methods

1.1 Experimental materials and Equipment

1.1.1 Experimental materials

Experiment major ingredients and auxiliary materials: dried beancurd sticks and experimental auxiliary materials are shown in table 1.

TABLE 1 Experimental major and minor materials

1.1.2 test apparatus

Experimental equipment: as shown in table 2.

TABLE 2 Experimental Equipment

1.2 preparation technology

Treatment of dried beancurd sticks

Soaking dried bean curd sticks, draining water, cutting the dried bean curd sticks (about 7 cm), frying the dried bean curd sticks, and draining oil.

Oil treatment

1, preparing materials: purified water, salt, sugar, light soy sauce and heating.

The oil processing technology comprises the following steps: heating edible oil, sequentially adding pepper, ginger slices, aniseed and scallion sections, frying the scallion sections to change color, fishing out the scallion sections, removing the scallion sections after oil control, putting the peppers into the peppers, frying the peppers to be dry, fishing out the peppers for standby, adding sesame, turning off the fire, adding the ingredients 1, and putting the fried beancurd sticks into the beancurd sticks.

Sterilization treatment

Bagging, vacuumizing, sterilizing, cooling and obtaining the finished product.

1.3 the key point of the manufacturing process

1.3.1 soaking dried beancurd sticks

The machine-made dried bean curd sticks with bright color, complete appearance, uniform state, no damage, no deterioration and low starch content are selected. Selecting warm water of 50 ℃, adding salt and white vinegar, mixing uniformly, and then putting the dried beancurd stick. When the dried beancurd sticks are soaked, the dried beancurd sticks are pressed on the upper side by a weight to prevent the dried beancurd sticks from floating and absorbing water unevenly.

1.3.2 throwing water from dried bean

When the dried beancurd sticks are soaked, a large amount of water can be absorbed, but the shelf life of finished products is influenced due to the fact that the water content is too high. Therefore, after the dried beancurd sticks are soaked, excess water is thrown off, the water content of the dried beancurd sticks is controlled, and then the dried beancurd sticks are cut into sections of about 7 cm.

1.3.3 Fried dried bean milk cream rolls

Heating the oil to 140 deg.C, placing into the processed wet-processed dried bean curd stick, frying for 30s, taking out, cooling, and removing the excessive oil.

1.3.4 frying oil

When the auxiliary materials are fried, the star anise, the pepper and the hot pepper are respectively soaked in cold water for about 20min in advance, then the star anise and the pepper are put into a pot with cold oil, fried slowly with soft fire to excite the fragrance of the spices, then fished out and discarded, and then the hot pepper is put into the pot and fried with soft fire.

1.4 Experimental scheme of instant spicy vegetable dried beancurd sticks

The basic formula of the experiment obtained after improvement is as follows:

the soaking formula comprises: 75g of dried bean curd sticks, 1000ml of warm water at 50 ℃, 5ml of white vinegar and 10g of salt.

Seasoning formula: 44.8ml of soybean oil, 18.6g of green onion, 10.6g of ginger, 2.2g of anise, 1.2g of pepper, 2.4g of hot pepper, 4.8g of sesame, 0.5g of salt, 2.2ml of light soy sauce, 1.2g of sugar and 14.4ml of hot water.

The preparation method comprises the following steps:

(1) Preparing fried bean curd sticks; the preparation method of the fried dried beancurd sticks comprises the following steps: mixing 75g of dried beancurd stick, 10g of salt, 5ml of white vinegar and 50 ℃ water, soaking for 100min until the water is over the dried beancurd stick, drying after soaking until the water content is 48%, and frying at 140 ℃ for 30s.

(2) The oil comprises: 44.8ml of soybean oil, 18.6g of scallion, 10.6g of ginger, 2.2g of anise, 1.2g of pepper, 2.4g of hot pepper, 4.8g of sesame, 0.5g of salt, 2.2ml of light soy sauce, 1.2g of sugar and 14.4ml of hot water at 70 ℃.

The preparation method of the oil material comprises the following steps:

1) Soaking fructus Anisi Stellati, capsici fructus and fructus Zanthoxyli in water for 15min respectively, taking out after the water submerges the materials;

2) Putting anise and hot pepper in a pot, heating to 120 ℃ and frying for 15min, taking out the anise and the hot pepper, frying the hot pepper and the hot pepper for 15min at 180 ℃, keeping the temperature, adding shallot and frying for 12min, taking out ginger slices, shallot and hot pepper, stopping heating, adding sesame and frying for 5min to obtain a material 1;

3) Mixing the material 1 obtained in the step 2), light soy sauce, sugar, salt and water.

(3) The fried bean curd sticks and the oil are mixed according to the mass ratio of 24.5:11 and mixing.

According to the influence of the pretreatment process of the dried beancurd sticks on finished products, which is obtained through preliminary experiments, the influence of the temperature of water, the amount of salt, the amount of white vinegar, the water content of wet dried beancurd sticks and the temperature and time of fried dried beancurd sticks on the shelf life of the dried beancurd sticks is large, so that the 6 single factors are optimized to obtain the optimal ratio.

1.4.1 Effect of soaking Water temperature on Dry Bean curd bamboo soaking time

Taking 75g of dried bean curd sticks as a reference, soaking the bean curd sticks in pure water at 20 ℃,30 ℃,40 ℃,50 ℃ and 60 ℃, and recording the soaking time of the bean curd sticks at different water temperatures. Judging the influence of the water temperature on the dried beancurd stick soaking, and determining the optimal water temperature of the soaked dried beancurd sticks.

1.4.2 Effect of salt on Wet dried beancurd stick quality

The salt content gradient was set to 5g, 10g, 15g, 20g, and 25g based on 1L of water, and the salt content gradient was set to 0.5%, 1%, 1.5%, 2%, and 2.5% by mass of a saline solution. Wherein the water temperature is the optimum temperature of the experiment, and the optimum addition amount of the salt is determined by the foaming time and sensory evaluation.

1.4.3 Effect of white Vinegar on Wet-Dry bamboo quality

The method comprises the steps of taking 1L of water as a reference, adding 0ml, 5ml, 10ml, 15ml and 20ml of white vinegar with the dosage gradient of 0%, 0.5%, 1%, 1.5% and 2% of vinegar aqueous solution by mass fraction respectively, and setting the dosage of water and salt as the optimal result of the experiment. The optimal addition amount of white vinegar was determined by the soaking time and sensory evaluation.

1.4.4 Effect of soaking time on Wet-Dry bamboo quality

Salt and white vinegar were added to water with 75g of dried bamboo, 1kg of water, the amount of white vinegar and salt being the optimum for the above experiment. The soaking time gradient was set at 20min,60min,80min,100min,120min. Measuring the cohesiveness, chewiness, adhesiveness and elasticity of the dried beancurd sticks in different soaking times by a texture analyzer. The texture analyzer adopts a TA11 cylindrical flat-bottom probe, and the set parameters are that the height is 10mm, the interval time is 5s, the deformation is 10%, the detection speed is 30mm/min, the initial force is 0.5N, and the post-detection speed is 10mm/min.

1.4.5 influence of moisture content on quality of Wet-Enshed bamboo

The water content can be used as one of the quality indexes of food, and the proper water content can keep the quality of the food and prolong the shelf life of the food. Firstly, the soaked bean curd sticks are weighed after being thrown with water by a draining basket, then the soaked bean curd sticks are dried to constant weight and then weighed again, and then the moisture content of the wet bean curd sticks is calculated. The water content of the dried beancurd sticks is reduced to 48 percent by throwing water.

1.4.6 Effect of frying temperature and time on the quality of dried beancurd stick finished product

After the dried beancurd sticks are fried, the fragrance of the dried beancurd sticks can be stimulated to a great extent. Therefore, the dried beancurd sticks can be simply fried after being soaked, so that the dried beancurd sticks have the fragrance of all around and are chewy and delicious. In the experiment, the oil temperatures of 110 ℃,120 ℃,130 ℃,140 ℃,150 ℃ and the time of 20s,30s and 40s are set to fry the dried beancurd sticks, and the proper frying temperature and time are obtained by combining texture instrument data with sensory evaluation.

1.4.7 orthogonal Experimental design

The method comprises the following steps of performing single-factor test on four single factors of water temperature, white vinegar, soaking time and frying temperature which have great influence on the soaking of dried beancurd sticks, and determining the appropriate temperature range of the water temperature through the analysis of experimental results of the four factors: at 40-60 deg.C, the optimal concentration of white vinegar is 0.5-1.5%, the optimal concentration of salt is 1.5-2.5%, the optimal soaking time is 80-120min, and the optimal frying temperature is 130-150 deg.C. And determining the most suitable soaking process by using a sensory evaluation method according to the experimental result, and optimizing the prepared spicy instant dried beancurd sticks. The factor levels are shown in Table 3.

TABLE 3 orthogonal test factor horizon

1.4.8 Sterilization in boiling Water bath

The heat sterilization treatment can treat toxic substances, biotoxin and the like in food, and has simple operation and strong controllability, so the heat sterilization treatment is more and more widely applied in the field of food processing. The instant bean curd sticks with spicy taste of the prefabricated vegetables are fried at high temperature in the early treatment process, and part of bacteria and other microorganisms are killed. And after the product is subjected to vacuum packaging, the product is subjected to boiling water bath sterilization, so that the safety of the food is ensured to a greater extent.

1.5 evaluation index

1.5.1 evaluation index of Wet-rot bamboo

TABLE 4 sensory evaluation method of wet-rot bamboo

1.5.2 evaluation index of spicy dried bean curd stick finished product

TABLE 5 sensory evaluation method of spicy dried bean milk cream rolls

1.5.3 sensory evaluation method of storage time of spicy dried beancurd sticks

TABLE 6 sensory evaluation method for storage quality of spicy dried beancurd sticks

2. Results and analysis

2.1 influence of Water temperature on quality of dried bamboo

The temperature of the water affects the time for the dried beancurd sticks to foam. The proper water temperature not only accelerates the foaming of the dried beancurd sticks, but also ensures that the dried beancurd sticks foam uniformly inside and outside. The excessive water temperature can cause the beancurd sticks to be incompletely soaked and have hard cores inside. However, if the water temperature is low, a large amount of time is needed for soaking the dried beancurd sticks, the surfaces of the dried beancurd sticks are soft and rotten after long-time soaking, a large amount of scraps are generated, and the appearance is not good.

As can be seen from fig. 1, the soaking time of the dried beancurd sticks is gradually reduced along with the increase of the water temperature. When the water temperature is 10-50 ℃, the time for soaking is gradually reduced. When the water temperature exceeds 50 ℃, the soaking time of the dried beancurd sticks is not shortened any more, the appearance is not good, the surfaces of the dried beancurd sticks are chipped, parts of the dried beancurd sticks are white, and the soaking is not uniform. The dried beancurd sticks foamed by water at 50 ℃ are selected, so that the using time is short, and the dried beancurd sticks are golden in color and luster and glossy; the shape is complete, the edge damage is small, and the surface chipping is less; the tissue state is uniform, the tendon and the channel are not easy to break, and the soaking and the foaming are also uniform. Therefore, the dried beancurd sticks are soaked in water of 50 ℃.

2.2 Effect of salt on Wet dried beancurd stick quality

Most of the dried beancurd sticks on the market are deeply processed, and the seasoning taste only stays on the surface of the dried beancurd sticks and does not permeate into the dried beancurd sticks. The taste is delicious in the mouth and the aftertaste is slight; or too salty in the mouth, and the aftertaste is right. The experiment shows that a proper amount of salt is added during the soaking process, so that the dried beancurd sticks have uniform taste, the soaking process of the dried beancurd sticks is accelerated, and the dried beancurd sticks are soaked in the salt water to play a disinfecting role.

As shown in FIG. 2, when the amount is less than 20g, the soaking time of the dried beancurd sticks is gradually shortened as the salt is increased. When the salt content is higher than 20g, the soaking time of the dried beancurd sticks is not changed.

As shown in the combined figure 3, the sensory score of the dried beancurd sticks is higher and higher with the increase of the salt content, and the taste is more delicious. When the salt content is higher than 20g, the dried beancurd sticks are salty in taste and the scores are suddenly reduced. When the addition amount of the salt is 20g, the dried beancurd sticks are shortest in soaking time, uniform in tissue state, even in soaking and even in taste, chewy but not hard, fresh, fragrant and delicious. Therefore, 20g of salt is suitable for soaking the dried beancurd sticks.

2.3 Effect of white Vinegar on the quality of Wet-rot bamboo

The preliminary test shows that a proper amount of white vinegar not only can accelerate the soaking of the dried beancurd sticks, but also can improve the quality of the dried beancurd sticks. The dried beancurd stick soaked by the white vinegar in a proper proportion not only has short time, but also has uniform surface tissue state, complete appearance, no damage or chipping, tough texture, elasticity, difficult breakage and chewy property.

As shown in FIG. 4, when the amount of the white vinegar is less than 10ml, the dried beancurd sticks are brittle after being soaked and have poor texture. When the amount of the white vinegar is more than 10ml, the product is slightly heavy, and is relatively sour. When the amount of the white vinegar is 10ml, the dried beancurd sticks are golden yellow in color, have very uniform color and luster, are completely soaked, have no hard cores inside, are complete in shape, have no fragments or damages and are elastic when being chewed. Therefore, experiments show that the effect is better when 10ml of white vinegar is used for soaking the dried beancurd sticks.

2.4 Effect of soaking time on Wet-Dry bamboo quality

With the increase of the soaking time, the dried beancurd sticks continuously absorb water until the dried beancurd sticks are in a saturated state. In the soaking process, the dried beancurd sticks absorb water, and the tissue state and the like are also changed.

As shown in fig. 5, the swelling time of the dried beancurd sticks is increased, which results in an increase in the water content of the product, so that the product becomes soft, and the chewiness, stickiness and cohesion are reduced. The elasticity of the dried beancurd sticks is increased and then reduced due to the fact that the dried beancurd sticks become soft after absorbing certain moisture, the elasticity of the dried beancurd sticks is increased, the dried beancurd sticks always absorb the moisture and become softer, and the elasticity of the dried beancurd sticks is gradually reduced.

As can be seen from fig. 6, the sensory score was the highest when the soaking time was 100min. The color of the dried beancurd sticks is golden, uniform and glossy; the shape is complete, the edge is not damaged, and the foam is uniform; the tissue state is uniform, and the dried beancurd sticks are not easy to break and have elasticity. Therefore, the longer the soaking time, the better the chewiness, stickiness, cohesion and elasticity of the dried bean curd sticks. However, when the soaking time was 100min, the chewiness was 0.657mj, the tackiness was 1.033N, the cohesiveness was 0.657Ratio, and the elasticity was 1.153mm, the wet dried bean curd stick state was the best.

2.5 influence of moisture content on quality of Wet-processed bamboo

The dried beancurd sticks can absorb a large amount of water after being soaked, and the soaked dried beancurd sticks are subjected to water throwing treatment. Comparing the dried beancurd sticks subjected to water throwing with the dried beancurd sticks subjected to water throwing. From Table 7, it can be seen that the moisture content of the dried beancurd sticks after water throwing is less than or equal to 48%, and the dried beancurd sticks are superior to the dried beancurd sticks without water throwing treatment in the aspects of taste, appearance, color and the like.

Wet base: weight of soaked bean curd sticks

Dry basis: dried bean curd stick with constant weight

TABLE 7 influence of moisture content on the quality of Wet-Enshed beancurd bamboo

2.6 Effect of frying temperature and time on dried beancurd stick quality

Influence of frying temperature and frying time on taste of dried bean milk cream rolls

After the dried beancurd sticks are soaked and foamed, a large amount of water is remained, the dried beancurd sticks are fried at a proper oil temperature, the quality of the dried beancurd sticks, such as texture, flavor and the like, is further influenced, meanwhile, a protective layer can be formed on the surfaces of the dried beancurd sticks by starch gelatinization, the water in oil at the later stage is blocked, and the quality guarantee period of the dried beancurd sticks is prolonged. The frying temperature is too low, the surface of the dried beancurd sticks is not changed, and the dried beancurd sticks become hard due to the fact that a large amount of oil is absorbed. When the frying temperature is too high, the surface of the dried beancurd sticks is crisp and can be rotten when meeting water.

As can be seen from fig. 7, the taste of the dried beancurd sticks gradually improved as the oil temperature and time increased, but the quality of the dried beancurd sticks was degraded when the oil temperature reached 140 ℃ and the frying time exceeded 30 seconds. When the oil temperature is lower than 140 ℃ and the frying time is lower than 30s, the bean curd sticks have large oil absorption, no great change in appearance color and greasy taste. When the oil temperature is higher than 140 ℃ and the time is higher than 30s, the color of the dried beancurd sticks is yellow brown, the surface of the dried beancurd sticks is foamed, and the dried beancurd sticks are dry and hard to chew. When the frying temperature is 140 ℃ and the frying time is 30s, the dried beancurd sticks are golden yellow and the appearance is complete; the mouth feel is soft and tender, the chewiness is better, and the elasticity is not lost; the bean fragrance is diffused all around, the lip and teeth are fragrant, and the sensory score is higher, so that the wet bean curd sticks are fried for 30s by oil at the temperature of 140 ℃.

Influence of frying temperature on dried bean curd stick quality

After the dried beancurd sticks are fried by different oil temperatures, the cohesiveness, elasticity, stickiness, chewiness and the like of the dried beancurd sticks are changed, and the dried beancurd sticks cannot be described in detail through simple sensory evaluation. Therefore, the frying time was set to 30s, and the texture parameters were as described above. As shown in FIGS. 8,9, 10 and 11, when the oil temperature is 140 ℃, the viscosity of the dried beancurd sticks is 0.57N, the cohesiveness is 0.81Ratio, the elasticity is 0.933mm, and the chewiness is 0.777 mj. At the moment, a layer of soft shell is formed on the surface of the dried beancurd stick, the color is golden yellow, the dried beancurd stick is glossy, and the dried beancurd stick is not greasy when tasted; the chewing gum is chewed, is soft, fragrant and delicious, and does not lose elasticity; meanwhile, after being fried in oil at 140 ℃, the water in the dried beancurd sticks is reduced, and the quality guarantee period of the products can be prolonged. Combines sensory evaluation, and is suitable for preparing the dried beancurd sticks by frying in oil at the temperature of 140 ℃.

2.7 orthogonal test and analysis of results

According to the single-factor experimental result, a four-factor three-level orthogonal test is selected to optimize the pre-made spicy instant dried beancurd sticks, and the orthogonal result is shown in table 8.

TABLE 8 results of orthogonal experiments

The comprehensive evaluation results of different combinations of single-factor experiments can be analyzed by the table, and the influence of each factor on the prepared spicy dried beancurd sticks with vegetable flavor is A>D>B>C, the most influenceable factor is the water temperature, which affects the mouthfeel and quality of the product, and secondly the frying temperature, salt and white vinegar. The optimal formula combination is A obtained by orthogonal experiments ₂ B ₂ C ₃ D ₂ Namely water temperature of 50 ℃, salt of 20g and white vinegar of 15ml, and frying temperature of 140 ℃.

The highest sensory score for the orthogonal test was A ₂ B ₂ C ₃ D ₂ And the optimal combination of each single factor is A ₂ B ₂ C ₂ D ₂ . To determine the best formulation, parallel experiments were performed to verify both formulations. As can be seen from the experiment, A ₂ B ₂ C ₃ D ₂ Slightly sour in mouth feel, apt to make tasting uncomfortable, and A ₂ B ₂ C ₃ D ₂ The taste was spicy and tasty, and no sour taste, and the results are shown in Table 9. Can be derived from ₂ B ₂ C ₂ D ₂ Sensory evaluation of (A) ₂ B ₂ C ₃ D ₂ High, therefore A ₂ B ₂ C ₂ D ₂ Is the optimal combination. The color of the dried beancurd sticks is golden yellow and the dried beancurd sticks are uniform in size; the spicy rice tastes moderately spicy and chewy.

Table 9 verifies the results of the experiments

3. Sterilization and shelf life

3.1 Hot Water bath Sterilization

After vacuum packaging, at a water temperature of 100 ℃, a part of microorganisms and bacteria will be killed. The production process uses normal pressure sterilization, thus greatly reducing energy consumption and production cost. The preparation time of the prefabricated spicy vegetable bean curd sticks is 12 months and 19 days, and the prefabricated spicy vegetable bean curd sticks are placed at normal temperature after being sterilized in boiling water bath. Every other month, the samples were checked.

The first checking time is 1 month and 19 days, and the product has golden color, normal smell and light bean curd stick fragrance. The tissue state of the dried beancurd sticks is good, and the appearance is complete without damage and chipping. The taste is the normal spicy taste of the dried beancurd stick, has the bean fragrance and the sesame fragrance of the dried beancurd stick, is spicy and delicious, and is chewy when being chewed.

The second inspection time is 2 months and 19 days, the color and luster of the product is goose yellow, the smell is not abnormal, and the fragrance of the dried beancurd sticks can be still smelled. The texture is good, the edges are not damaged and not adhered together. The taste is salty and savory, and the taste is fine and thin, the bean flavor and the sesame flavor are full of the oral cavity, and the taste is elastic but not sticky to teeth.

The third checking time is 3 months and 19 days, the product is light yellow, the smell is normal, and the fragrance of the dried beancurd sticks is light. The tissue state is good, no rot and mould growth exist, but the inside of the dried beancurd stick absorbs oil content due to long standing time, the surface oil content is reduced, and the dried beancurd stick is slightly adhered and needs to be pulled out manually due to vacuum packaging. Tasting, the mouthfeel is slightly light, but the taste is not light as a cold dish.

4. Conclusion

In the experiment, the machine-made dried beancurd sticks are used as a main raw material, and key factors influencing the quality of the finished product are found as follows: the soaking water temperature, the salt water ratio, the white vinegar water ratio and the frying temperature. The following conclusions were drawn experimentally:

(1) Dried bean soaking liquid: the optimal soaking water temperature of dried beancurd stick is 50 deg.C based on 1L water, the salt amount is 20g, and the white vinegar is 10ml. 75g of dried beancurd sticks can be soaked, so that the obtained beancurd sticks are uniform in color and luster and glossy in surface; proper elasticity and spicy and delicious taste.

(2) Draining dried beancurd sticks: the draining basket is used for draining the dried beancurd sticks, so that the water content of the dried beancurd sticks is lower than 48%, the quality guarantee period of the product can be prolonged, and more oil materials are absorbed by the dried beancurd sticks at the later stage, so that the dried beancurd sticks are more delicious.

(3) Frying dried beancurd sticks: the wet dried beancurd sticks are fried for 30s at the oil temperature of 140 ℃, the bean fragrance of the dried beancurd sticks is fully excited, meanwhile, the water content of the dried beancurd sticks is reduced in the frying process, and the shelf life can be prolonged.

(4) Determination of the sterilization method: the fried bean curd sticks are vacuumized and packaged without adding preservatives, and after the products are sterilized in hot water bath, the products are stored for a long time and placed in a constant-temperature incubator. The prepared dish spicy dried beancurd sticks can be stored for 3 months at normal temperature.

The product with the optimal formula has uniform color, is golden yellow and has certain luster; regular shape, uniform size and no impurities; the flavor is normal, and has light bean curd stick flavor and sesame flavor; the seasoning has the advantages of proper flavor, moderate spicy taste, moderate aftertaste and moderate greasiness; the tissue state is uniform, and the dried beancurd sticks are not easy to break and chewy.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and amendments can be made without departing from the principle of the present invention, and these modifications and amendments should also be considered as the protection scope of the present invention.

Claims

1. A spicy instant dried bean curd stick is characterized by comprising: dried beancurd sticks and oil; the mass ratio of the dried beancurd sticks to the oil is 20.5-28.5: 9 to 13;

the oil is prepared from the following components in parts by mass: 40.8 to 48.8 portions of oil, 16.6 to 20.6 portions of scallion, 8.6 to 12.6 portions of ginger, 2.0 to 2.4 portions of anise, 1.0 to 1.4 portions of pepper, 2.2 to 2.6 portions of hot pepper, 3.8 to 5.8 portions of sesame, 0.4 to 0.6 portion of salt, 2.0 to 2.4 portions of light soy sauce, 1.0 to 1.4 portions of sugar and 12.4 to 16.4 portions of water.

2. The spicy instant dried beancurd stick according to claim 1, wherein the dried beancurd stick is fried dried beancurd stick; the preparation method of the fried bean curd sticks comprises the following steps: mixing dried beancurd stick, salt, white vinegar and water, soaking, drying and frying.

3. The spicy instant dried beancurd stick according to claim 2, wherein the temperature of the water is 45-55 ℃; the final concentration of the salt is 1.5-2.5 wt%; the final concentration of the white vinegar is 0.5-1.5 vt%; the soaking time is 90-110 min.

4. The spicy instant dried beancurd stick according to claim 2, wherein the dried beancurd stick contains less than or equal to 48% of water; the frying temperature is 130-150 ℃; the frying time is 25-35 s.

5. The spicy instant dried beancurd stick according to claim 1, wherein the oil is prepared by the following steps:

6. The spicy instant dried beancurd stick according to claim 5, wherein the frying temperature of the aniseed and the hot pepper in the step (2) is 115-125 ℃, and the frying time is 13-17 min.

7. The spicy instant dried beancurd stick according to claim 5, wherein the frying temperature of the pepper and the ginger in the step (2) is 175-185 ℃, and the frying time is 13-17 min.

8. The spicy instant dried beancurd stick according to claim 5, wherein the frying time of the scallion in the step (2) is 10-14 min.

9. The spicy instant dried beancurd stick according to claim 5, wherein the frying time of the sesame in the step (2) is 4-6 min.

10. The method for preparing instant spicy dried beancurd sticks as claimed in any one of claims 1 to 9, wherein dried beancurd sticks and oil are mixed.