CN114391637A - A kind of short-term fermentation and flavor-enhancing sprouts and preparation method thereof - Google Patents

Abstract

The invention provides a short-term fermentation and flavor-enhancing sprouts and a preparation method. The sprouts are pre-treated by drying, pickling, cleaning, water control, adding sugar, etc.; The thalline preparation is sealed and fermented after mixing with sprouts, and sprouts are obtained after 80-100 days. In the method, by pre-processing the sprouts and adding Bacillus pumilus Y1, the fermentation time is shortened from 4-6 months to 80-100 days, and the sprouts products with stable quality, improved flavor and higher quality are obtained .

Description

A kind of short-term fermentation and flavor-enhancing sprouts and preparation method thereof

technical field

The invention belongs to the technical field of food fermentation, and in particular relates to a short-term fermentation flavor-enhancing sprout and a preparation method.

Background technique

Sprouts are one of the most famous processed foods in my country. They have a long history of production and exquisite craftsmanship. They are famous for their unique flavors such as "fragrant, crisp, tender and fresh", among which Yibin sprouts are particularly famous. Sprouts are prepared by fermentation. During the fermentation process, a variety of microorganisms work together to give them a special flavor, taste and color. They are rich in nutrients and rich in various amino acids and vitamins.

At present, sprouts are generally produced by the traditional natural fermentation method. The sprouts are stored in fermentation tanks or ceramic jars for natural fermentation, which generally takes 4-6 months. The operation and control of traditional fermentation methods are relatively extensive, there is no unified standard, the fermentation conditions are uncertain, the fermentation time is long, there are differences in the fermentation products between different batches, the product flavor is uneven, and the product quality is unstable, which is not suitable for large-scale production. Industrial production. Therefore, there is an urgent need in the art for a method for preparing sprouts that can effectively shorten the fermentation period, the quality of the fermented product is stable, and the flavor is good.

SUMMARY OF THE INVENTION

The invention aims to overcome the problems of long preparation time and unstable quality of sprouts in the prior art, and provides a short-term fermentation and aroma-enhancing sprouts and a preparation method. In the method, after pretreatment of fresh sprouts, Bacillus pumilus is added for fermentation, the fermentation time is shortened from 4-6 months to 80-100 days, the flavor of sprouts is improved and improved, and the quality of products is improved. more stable.

For achieving the above object, the technical scheme adopted in the present invention is as follows:

A preparation method of short-term fermented flavor-enhancing sprouts, comprising the following operation steps:

S100: Pretreatment of sprouts

Weigh fresh sprouts, dry them, draw strips, and remove impurities; add salt, mix well, and then pickle. After pickling, carry out the first panning, stacking to control water, and the second panning and drying; Boil the sugar with water until the color and fragrance are suitable, add it to the dried sprouts, mix evenly, stack to control the water, and set aside;

S200: Preparation of inoculum

Activating the strain to obtain a bacterial preparation, the strain includes Bacillus pumilus Y1, and the preservation number of the Bacillus pumilus Y1 is SICC 1.1133;

S300: Fermentation Treatment

The thalline preparation is added to the pretreated sprouts, and mixed evenly; the mixed thallus sprouts are compressed and put into a fermentation kiln or a pottery altar, sealed, protected from light, and fermented for 80-100 days.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, the fresh sprout is dried, and the water loss rate is controlled within the range of 20% to 25%.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, the added amount of the salt is 8% to 10% of the weight of the fresh sprout;

The pickling time is 45-50h, and the stacking water control time after pickling is ≥12h.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, the sugar is one or more of white sugar, brown sugar or rock sugar, and the added amount of the sugar is 10% to 15% of the weight of the fresh sprout. %.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, the moisture content of the sprout after pretreatment is less than or equal to 80%.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, the step S200: preparation of inoculum, specifically including:

S210, inoculating the bacterial strain into a nutrient agar liquid medium in a conical flask, and at a temperature of 30-37° C., culturing on a 120 rpm shaker for 24-48 hours to obtain a fermentation bacterial liquid;

S220, centrifuge the fermented bacterial liquid at 3000rpm for 10min to obtain thalline;

S230, mixing the bacterial cells with sterile distilled water or sterile physiological saline to prepare a bacterial cell preparation.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, in step S230, the addition amount of the sterile distilled water or sterile physiological saline is determined with reference to the volume of the nutrient agar liquid medium, and the The volume ratio of bacterial distilled water or sterile physiological saline to the nutrient agar liquid medium is 0.5-1:1.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, the viable count of the Bacillus pumilus Y1 in the bacterial preparation is ≥1.0×10 ⁹ cfu/mL, and the bacterial preparation The inoculation amount is 0.1-0.2% of the fresh weight after pretreatment.

In order to further improve the quality of the sprout product and obtain the sprout product with stable quality, the step S300: fermentation treatment, further comprising: adding 1% to 2% of spice powder, the spice powder including prickly ash, star anise, shanna and cinnamon , the added amount of pepper, star anise, shanna and cinnamon is 2:10:5:5.

A short-term fermented flavor-enhancing sprout is prepared by the preparation method described in any of the above.

Compared with the prior art, the beneficial effects of the present invention are:

In the present invention, sprouts are pre-treated, and the drying moisture, the amount of salt, the pickling time and the water control time are controlled through a specific treatment process, and boiled sugar is added for seasoning and coloring, so as to obtain sprouts with good flavor and quality in the future. Preparing vegetable products.

By adding Bacillus pumilus Y1 (the deposit number is SICC 1.1133) to ferment the sprouts, the dominant flora can be rapidly formed during the fermentation process, so that the sprouts can enter the active fermentation stage more quickly, effectively reducing the fermentation cycle from the original 4-6 months, shortened to 80-100 days; in the sprout products after fermentation, esters and olefins increased, which produced flavor substances such as linalool and β-sesquiphellandrene, which gave sprout products unique During the fermentation process, reducing sugar increases, which further promotes microbial fermentation, and undergoes hydroxylamine reaction with amino acids during the fermentation process to increase the flavor; the nitrite content in the early and final stages of fermentation is reduced, and sprouts are safer to eat. That is, the preparation method of the present invention can obtain sprout products with short fermentation period, stable fermented product quality, improved flavor, and edible safety; and the preparation method has short period of time, easy operation and control, stable product quality, and is suitable for large-scale industrial production.

Description of drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that are used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present application. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without any creative effort.

FIG. 1 is the GC-MS analysis plasma spectrum of the sprout products of Example 4 and Example 1.

FIG. 2 is a graph showing the change of reducing sugar content during the fermentation of Example 4 and Example 1 for 90 days.

FIG. 3 is a graph showing changes in nitrite content during the 90-day fermentation in Example 4 and Example 1.

Detailed ways

In the following, only certain exemplary embodiments are briefly described. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the disclosed embodiments. Accordingly, the drawings and description are to be regarded as illustrative in nature and not restrictive.

The following Bacillus pumilus Y1 was purchased from the Sichuan Provincial Microbial Resource Platform Culture Collection and Management Center, and the strain collection number is SICC 1.1133.

Example 1

This embodiment provides a preparation method of short-term fermented flavor-enhancing sprouts. Including the following steps:

S100: Pretreatment of sprouts

Weigh fresh sprouts, dry them to wilt, and after the water loss rate reaches 20% to 25%, make strips to obtain uniform strip sprouts, and remove old leaves, yellow leaves and impurities.

Add salt to the sprouts after drying and striping. The amount of salt added is 10% of the weight of the fresh sprouts. After mixing evenly, pickle them for about 48 hours. The pickled sprouts are washed for the first time. Wash and pan until the sprouts have no salty taste in the mouth, and control the water by stacking. The water control time is not less than 12h, and the water control time can be controlled at about 15h. After controlling the water, turn the vegetable blanks, select and remove impurities, and then carry out the second panning. After panning, dry the vegetables for later use.

The water loss rate is controlled within the range of 20% to 25%, and the amount of salt added and the pickling time are controlled to ensure that the salt is dispersed evenly during the pickling process, and the intracellular water is fully removed to ensure that the sprouts are not prone to spoilage in the subsequent fermentation.

Weigh the sugar according to 15% of the weight of the fresh sprouts, the sugar is rock sugar, boil the sugar with water, boil it until the color and aroma of the syrup are suitable, cool it, add it to the sprouts on the drying rod, mix well, and then stack The water is controlled so that the moisture content of the treated sprouts is controlled within the range of 80%, and the pre-treated sprouts are obtained and used for later use.

Adding sugar syrup is used for pickling sprouts, coloring, and providing carbon source for the growth of microorganisms in the subsequent fermentation process.

S200: Preparation of inoculum

The purchased strain of Bacillus pumilus Y1 (Accession No.: SICC1.1133) was activated and cultured to obtain a bacterial preparation.

Specifically, the purchased Bacillus pumilus Y1 was picked with an inoculating needle, streaked on a nutrient agar medium plate, and cultured at a temperature of 30-37° C. for 48 hours. Then, pick a single colony with an inoculating needle and inoculate it into the sterilized nutrient agar liquid medium in a conical flask, and culture it on a shaker at 120 rpm for 48 hours at 30-37° C. to obtain a fermentation broth.

The fermented bacterial liquid was centrifuged at 3000 rpm for 10 min, the supernatant was discarded, and the bacterial slurry was obtained.

Dilute the obtained bacterial cell paste with sterile distilled water or sterile physiological saline, and the volume ratio of the amount of sterile distilled water or sterile physiological saline to the original nutrient agar liquid medium is 1:1. That is, using sterile distilled water or sterile physiological saline to dilute the bacterial slurry to the bacterial concentration of the fermented bacterial liquid, that is, the prepared bacterial preparation.

Among them, the nutrient agar medium: peptone 1%, beef extract 0.5%, sodium chloride 1%, agar 1.2%, pH 7.2-7.4. Nutrient agar liquid medium: peptone 1%, beef extract 0.5%, sodium chloride 1%, pH 7.0-7.6.

The bacterial preparation was tested by viable count method (dilution plate culture count method), and the viable count of Bacillus pumilus Y1 was ≥1.0×10 ⁹ cfu/mL.

S300: Fermentation Treatment

The prepared thalli preparation is inoculated into the pre-treated sprouts in the form of spraying, and the inoculation amount of the thalli preparation is about 0.1% of the weight of the fresh sprouts. During the spraying process, the sprouts are constantly turned to ensure uniform inoculation.

Then, add 1% spice powder based on the weight of sprouts, and mix well. The spice powder is composed of prickly ash, star anise, shanna and cinnamon powder, wherein the prickly ash, star anise, shanna and cinnamon are obtained by mixing 2:10:5:5.

The sprouts after being inoculated and mixed with spices are packed into a pottery jar layer by layer, the jar mouth is sealed, placed in a cool and dark place, and fermented for 90 days to obtain a sprout product. The sprout product is yellow-brown, moist and shiny, crispy and delicious.

Example 2

The difference from Example 1 is:

In the pretreatment of sprouts, the amount of salt added was 8% of the weight of fresh sprouts, the pickling time was 50h, and the amount of sugar added was 10% of the weight of fresh sprouts.

In the preparation of inoculum, the volume ratio of the amount of sterile distilled water or sterile physiological saline to the original nutrient agar liquid medium is 0.5:1 when the bacterial slurry is diluted.

In the fermentation treatment, the bacterial preparation was inoculated in the sprouts by spraying, and the inoculation amount of the bacterial preparation was 0.2% of the weight of the fresh sprouts.

The sprouts after inoculation and mixing with 1% spice are layered tightly, sealed and protected from light in the fermentation cellar, and fermented for 80 days to obtain sprouts products.

Example 3

The difference from Example 1 is:

In the pretreatment of sprouts, the amount of salt added was 8% of the weight of fresh sprouts, the pickling time was 45h, and the amount of sugar added was 12% of the weight of fresh sprouts.

In the preparation of inoculum, the volume ratio of the amount of sterile distilled water or sterile physiological saline to the original nutrient agar liquid medium is 0.5:1 when the bacterial slurry is diluted.

In the fermentation treatment, the microbial cell preparation was inoculated into the sprouts by spraying, and the inoculation amount of the microbial cell preparation was 0.1% of the weight of the fresh sprouts.

The sprouts after inoculation and mixing of 2% spice powder are layered tightly, sealed and protected from light in the fermentation cellar, and fermented for 100 days to obtain sprouts products.

Example 4

This example is a comparative example of Examples 1-3.

The difference from Example 1 is that no inoculum preparation is carried out, but sterile distilled water or sterile physiological saline is directly used for water spray mixing, that is, the sprouts are not inoculated with the Bacillus pumilus Y1 strain. A sprout product was obtained after 90 days of fermentation.

Comparison of test results

(1) Analysis and determination of volatile substances

The sprout products obtained in Example 1 and Example 4 were subjected to analysis and determination of volatile substances.

Specifically, the sprouts were cut into pieces with sterilized scissors, 1.0 g of sprouts were weighed and placed in a 15 mL headspace injection bottle, 2.0 mL of saturated NaCl solution was added, and the solution was resolved at 230° C. for 5 min. Detection was performed by gas chromatography-mass spectrometry (GC-MS). The test results are shown in Figure 1 and Table 1.

Table 1 The sprout product volatile flavor substance content detection result of embodiment 1 and embodiment 4

Note: "-" means not detected.

the result shows:

In the sprout products of embodiment 1 and embodiment 4, alkenes and esters are obviously in the majority, marking that sprouts are fermented and mature;

The sprout product of Example 1 has more esters and olefins than the sprout product of Example 4, indicating that the sprout product of Example 1 is richer in flavor substances;

The sprout product of Example 1 produced significantly different flavor substances such as linalool and β-sesquiphellandrene after being fermented for 90 days. Linalool has a strong blue and sweet woody green scent, similar to rosewood scent, more like green tea green scent just out of the oven, not only floral scent of lilac, lily of the valley and rose, but also woody and fruity. Beta-sesquiphellandrene has fruit, grass, and wood flavors, and cinnamyl acetate has flower, fruit, and honey flavors, which enrich the flavor of fermented sprouts and give fermented sprouts a unique fragrance.

(2) Detection of reducing sugar content and detection of nitrite content

As shown in Figure 2, the sprouts of Example 1 significantly increased the reducing sugar content during the fermentation process. It is inferred that the decomposition of sprouts cellulose under the action of Bacillus pumilus Y1 and cellulase produces more reducing sugars. Reducing sugar can be used as a carbon source for microorganisms in fermentation to grow and reproduce, so that the flavor substances in sprouts are more abundant; reducing sugar can also undergo carbonyl ammonia reaction with amino acids produced in the fermentation process to increase flavor.

As shown in FIG. 3 , the nitrite content in Example 1 was significantly lower than that in Example 4 at the beginning and end of the fermentation. Surface inoculation of Bacillus pumilus Y1 effectively reduced the production of nitrite, and the sprout products had better flavor and better safety.

Claims (10)

1. A preparation method of short-term fermentation aroma-enhanced sprouts is characterized by comprising the following operation steps:

s100: pretreatment of bean sprouts

Weighing fresh bean sprouts, airing the fresh bean sprouts, cutting the fresh bean sprouts into strips, and removing impurities; adding salt, mixing, pickling, washing, stacking, draining water, washing, and air drying; adding water into sugar, decocting until the color and flavor are appropriate, adding into the dried bean sprouts, mixing well, and stacking for water control;

s200: preparation of microbial inoculum

Activating strains to obtain a thallus preparation, wherein the strains comprise bacillus pumilus Y1, and the preservation number of the bacillus pumilus Y1 is SICC 1.1133;

s300: fermentation treatment

Adding the thallus preparation into the pretreated bean sprouts, and uniformly mixing; and (3) tightly pressing the sprouts mixed with the thalli, filling the sprouts into a fermentation kiln or a pottery jar, sealing and keeping out of the sun, and fermenting for 80-100 days.

2. The method for preparing short-term fermentation aroma-enhanced sprouts according to claim 1, wherein the fresh sprouts are aired to a degree as long as possible, and the water loss rate is controlled within the range of 20-25%.

3. The method for preparing short-term fermentation aroma-enhanced sprouts according to claim 1 or 2, wherein the addition amount of the salt is 8-10% of the weight of fresh sprouts;

the curing time is 45-50 h, and the water control time of the stack after curing is more than or equal to 12 h.

4. The method for preparing short-term fermentation flavored bean sprouts according to claim 1, wherein the edible sugar is one or more of white sugar, brown sugar or crystal sugar, and the amount of the edible sugar is 10-15% of the weight of fresh bean sprouts.

5. The method for preparing short-term fermentation aroma-enhanced sprouts according to claim 1, wherein the moisture content of the pretreated sprouts is less than or equal to 80%.

6. The method for preparing short-term fermentation flavored sprouts according to claim 1, wherein the step S200: the preparation of the microbial inoculum specifically comprises the following steps:

s210, inoculating the strain into a nutrient agar liquid culture medium in a conical flask, and performing shake culture at the temperature of 30-37 ℃ and the rpm of 120 for 24-48 h to obtain a zymogen liquid;

s220, centrifuging the zymocyte liquid at 3000rpm for 10min to obtain thalli;

and S230, mixing the thalli with sterile distilled water or sterile normal saline to prepare a thalli preparation.

7. The method for preparing short-term fermented flavored sprouts according to claim 6, wherein in step S230, the addition amount of sterile distilled water or sterile physiological saline is determined by referring to the volume of the nutrient agar liquid medium, and the volume ratio of the sterile distilled water or sterile physiological saline to the nutrient agar liquid medium is 0.5-1: 1.

8. the method for preparing short-term fermentation aroma-enhanced sprouts according to claim 6 or 7, wherein the viable count of the Bacillus pumilus Y1 in the thallus preparation is more than or equal to 1.0 x 10⁹cfu/mL, wherein the inoculation amount of the thallus preparation is 0.1-0.2% of the weight of the fresh bud vegetables.

9. The method for preparing short-term fermentation flavored sprouts according to claim 1, wherein the step S300: the fermentation treatment also comprises the following steps: adding 1-2% of spice powder, wherein the spice powder comprises pepper, anise, rhizoma kaempferiae and cinnamon, and the addition amount of the pepper, the anise, the rhizoma kaempferiae and the cinnamon is 2: 10: 5: 5.

10. short-term fermentation flavored bean sprouts, which are prepared by the preparation method of any one of claims 1 to 9.

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