Feed selenium yeast and preparation method thereof
Technical field
The present invention relates to a kind of feed selenium yeast and preparation method thereof, particularly about a kind of barms and inorganic selenium source of selecting high-quality for use, adopt liquid, solid-state combined ferment technology to prepare the method for feed with selenium yeast, and according to the preparation-obtained feed selenium yeast of this method.
Background technology
Trace elements of selenium has and participates in that paddy Guang liver peptide peroxidase makes the humans and animals body avoid the destruction of free radical and radiation, keeps cellular respiration, immune response stimulating, protection liver, suppresses effect such as cancer cell.In the production of traditional feed and feed addictive, widely-used inorganic selenium---sodium selenite is as the replenishers of trace elements of selenium.But the toxicity of sodium selenite is big, uses or miscarriage, can cause serious adverse consequences, thereby developed countries such as America and Europe, Japan does not re-use this type of inorganic selenium source in animal feed.
Studies show that the bioavailability height of organic selenium, particularly selenium yeast can improve the blood selenium level in the animal body effectively, can be used as feed addictive and be used for the ruminant animal, is a kind of selenium supplement that market prospects are arranged very much.Selenium yeast is a kind of biologic product, brewer's yeast, candida utili have that growth and breeding is fast, fermentation period is short, to characteristics such as micro-absorptivity height, it is the ideal carrier that inorganic selenium is converted to organic selenium, after inorganic selenium enters yeast cells, form organic selenium (selenomethionine, selenium cystine) in the similar wholefood with amino acid or combined with protein, wherein organic selenium content accounts for more than 90% of total selenium, and can ignore inorganic selenium content in the selenium yeast, and its active and absorptivity are 10~20 times of inorganic selenium.Se content in the selenium yeast of the prior art is generally below 500mg/kg.
The preparation of China's selenium yeast at present also is in the laboratory research stage, and the actual production of being unrealized, correlative study also lack the exploration to the optimal conditions of rich selenium fermentation, does not possess the directive significance of large-scale production.
Summary of the invention
One object of the present invention is to provide a kind of method for preparing feed with selenium yeast, adopts simple and easy to do zymotechnique, and preparing a kind of selenium yeast of high Se content, and this method is easy to large-scale production enforcement.
Another object of the present invention is to provide a kind of selenium yeast for preparing according to described method, wherein contain the organic selenium and the active dry yeasr of high level, can be used as feed or feed addictive.
On the one hand, the invention provides a kind of microbial fermentation and prepare the method for feed with selenium yeast, it wherein mainly is the barms of selecting high-quality for use, be inoculated into earlier in the seeding tank fluid nutrient medium that adds sodium selenite and enlarge cultivation, and then be inoculated in the solid-state tray and ferment, obtain feed selenium yeast of the present invention after the drying.
According to specific embodiments of the present invention, microbial fermentation provided by the invention prepares feed and comprises with the method for selenium yeast:
The ratio of brewer's yeast in every ring 40~80ml is inoculated in the brewer's wort enriched medium (or claiming the one-level enriched medium), and 28~32 ℃ of vibrations were carried out one-level in 22~72 hours preferred 22~32 hours and are increased the bacterium cultivation;
Secondary seed medium (or claiming the secondary enriched medium) is heated to 55 ℃~65 ℃, (addition of AMS is decided according to the content of starch in the culture medium to add AMS, the amylase that every gram starch adding 6~10U enzyme is lived) the insulation hydrolysis is 2~3 hours, (addition of carbohydrase also is to decide according to the content of starch in the culture medium to add carbohydrase then, every gram starch adds the carbohydrase that 100~180U enzyme is lived), keep 55 ℃~65 ℃ saccharification 2~3 hours, be warming up to 100 ℃~125 ℃ sterilizations 15~30 minutes afterwards, add selenate or selenite again and make that selenium concentration reaches 20~25 μ g/ml in this culture medium; And this nutrient solution is cooled to below 35 ℃, the ratio in 8%~12% inserts and above-mentionedly increases saccharomyces cerevisiae liquid after bacterium is cultivated through one-level, carries out secondary in 22~48 hours in 28 ℃~32 ℃ shaken cultivation of temperature and increases bacterium and cultivate;
Increase bacterium liquid that bacterium cultivates and feed fermentation substrate and water according to 1~2 with above-mentioned through secondary: 10~20: 5~10 weight ratio mixing, 30~45 ℃ of condition bottom fermentations 36~78 hours, with the drying materials after the fermentation ends, pulverizing, promptly get feed selenium yeast finished product.
According to preferred specific embodiments of the present invention, in the method for the present invention, described brewer's wort enriched medium is made by the following method:
Brewer's wort adds the distilled water of 6~10 times of volumes, sugar degree regulation to 4~10 ripple woodss (Balling), and pH transfers to 5.5~6.5, sterilizes 15~30 minutes under 100~125 ℃ of temperature.
According to preferred specific embodiments of the present invention, in the method for the present invention, described secondary seed medium adds water by corn flour, wheat bran, nutritive salt and is mixed and made into, and specifically makes by the following method:
Corn flour 15~20 weight portions, wheat bran 3~8 weight portions, nutritive salt 1~2 weight portion add water 70~81 weight portions, mix, and pH transfers to 3.6~4.8 and makes.
According to preferred specific embodiments of the present invention, in the method for the present invention, described feed fermentation substrate (solid fermentation substrate) is made after adding the water mixing by corn flour, cotton dregs, dregs of beans, the rape dregs of rice, wheat bran, nutritive salt, interpolation selenate or selenite, specifically makes by the following method:
Corn flour 50~70 weight portions, cotton dregs 8~12 weight portions, dregs of beans 8~12 weight portions, the rape dregs of rice 4~8 weight portions, wheat bran 5~10 weight portions, nutritive salt 1~2 weight portion, selenate or selenite 0.5~1 weight portion mix, and make the feed fermentation substrate.
According to preferred specific embodiments of the present invention, in the method for the present invention, described nutritive salt be by potassium dihydrogen phosphate, ammonium sulfate, glucose according to 2~4: 8~12: 1~3 weight ratio mixes to be made.
According to preferred specific embodiments of the present invention, in the method for the present invention, describedly increase in the bacterium liquid and feed fermentation substrate and water blend step that bacterium cultivates through secondary, the pH value of described water is 5.0~7.0, the granularity of described feed fermentation substrate is 3~8mm, mix mixture to be piled the trapezoidal heap that height is 10~40cm after finishing, 30~45 ℃ of condition bottom fermentations 36~78 hours.
According to preferred specific embodiments of the present invention, in the method for the present invention, in the described baking step, the control bake out temperature is not higher than 60 ℃, preferably is not higher than 45 ℃.
According to preferred specific embodiments of the present invention, in the method for the present invention, the material grinding granularity after the described oven dry is passed through 20 mesh sieves by 80 mesh sieves, at least 95% by 40 mesh sieves, 100% at least 75%.
In of the present invention one preferred specific embodiments, microbial fermentation of the present invention prepares feed to carry out in accordance with the following methods with the method for selenium yeast:
Brewer's yeast on the test tube slant is inoculated in the ratio of every ring 40~80ml the brewer's wort enriched medium (distilled water that is added 6~10 times of volumes by brewer's wort is housed, sugar degree regulation to 4~10 ripple woodss, pH transfers to 5.5~6.5, under 100~125 ℃ of temperature, sterilize and made in 15~30 minutes) triangular flask in, bottle stopper beyond the Great Wall, and wrap with sealing film, under 28~32 ℃, 100~180 rev/mins conditions, vibrate and carried out one-level in 22~72 hours and increase bacterium and cultivate;
With secondary seed medium (by corn flour 15~20 weight portions, wheat bran 3~8 weight portions, nutritive salt 1~2 weight portion adds water 70~81 weight portions and mixes, pH transfers to 3.6~4.8 and makes) be heated to 55 ℃~65 ℃, add an amount of AMS (adding the amylase that 6~10U enzyme is lived) insulation hydrolysis 2~3 hours according to every gram starch in the culture medium, add an amount of carbohydrase (adding the carbohydrase that the preferred 120~160U enzyme of 100~180U is lived) then according to every gram starch in the culture medium, keep 55 ℃~65 ℃ saccharification 2~3 hours, be warming up to 100 ℃~125 ℃ sterilizations 15~30 minutes afterwards, cool to again below 50 ℃, sodium selenite solution is added in this culture medium by a certain percentage, make that selenium concentration reaches 20~25 μ g/ml in this culture medium, nutrient solution continues to be cooled to below 35 ℃, the above-mentioned saccharomyces cerevisiae liquid that increases the bacterium cultivation through one-level is inoculated by 8%~12% mass ratio, is 28 ℃~32 ℃ in temperature, stir culture was carried out secondary in 22~48 hours and is increased the bacterium cultivation under 100~180 rev/mins of conditions;
Increase bacterium liquid that bacterium cultivates and water (in advance with inorganic acid or organic acid HCl for example with above-mentioned through secondary, citric acids etc. are regulated pH to 5.0~7.0), the feed fermentation substrate is (by corn flour 50~70 weight portions, cotton dregs 8~12 weight portions, dregs of beans 8~12 weight portions, the rape dregs of rice 4~8 weight portions, wheat bran 5~10 weight portions, nutritive salt 1~2 weight portion, selenate or selenite 0.5~1 weight portion mix to be made, granularity is 3~8mm) with 1~2: 5~10: 10~20 weight ratio is evenly mixed, after mixing finishes it is piled the trapezoidal heap that height is the preferred 10~30cm of 10~40cm, simultaneously with floor heating 30~45 ℃ of condition bottom fermentations 36~78 hours, Tumble Dry after the fermentation ends, for reducing the destruction of bake out temperature to active component in the feed, in the described baking step, preferred control temperature is not higher than 60 ℃, more preferably below 40 ℃, material after will drying is afterwards pulverized, preferred grinding particle size passes through 80 mesh sieves at least 75%, at least 95% by 40 mesh sieves, 100% by 20 mesh sieves, and pulverizing the back packing is finished product.
The present invention also provides the feed for preparing according to the method described above selenium yeast.This feed is used in the selenium yeast, organic selenium content 600~1000 micrograms/g, and the yeast viable count is up to more than 1,800,000,000/g, and crude protein content is up to more than 32%.Feed selenium yeast of the present invention can be used as feed or feed addictive, be used for feeding animals particularly ruminant with the Selenium Supplement element.Related experiment shows, utilizes selenium yeast feeding animals of the present invention can increase the content of ruminant Ruzhong selenium; Reduce SCC number in the newborn body; Improve the calf survival rate; Reduce the breeding number of times of each gestation; Reduce disease incidence rate such as retention of afterbirth, hysteritis; Improve food conversion ratio, reduce the death rate, improve body disease-resistant power and immunity, accelerate the reaction of body vaccine.
In sum; the present invention selects the barms of function admirable for use; and adopt liquid, the fixed zymotechnique that closes; after postvaccinal culture medium being carried out degree of depth fermentation; can obtain a large amount of Se-enriched yeast products, thereby provide a kind of preparation method who is easy to the selenium yeast of large-scale production to reach according to the preparation-obtained selenium yeast of this method.Selenium yeast of the present invention and preparation method thereof has with advantage:
1, method of the present invention adopts liquid, the fixed zymotechnique that closes, and after postvaccinal culture medium being carried out degree of depth fermentation, obtains a large amount of Se-enriched yeast products, and the conversion ratio that adopts this technology can effectively improve selenium is avoided the generation of simple substance selenium.Solid state fermentation is produced selenium yeast with respect to pure liquid state fermentation simultaneously, and the simple cost of technology is lower, and the equipment less investment can be carried out large-scale production.
2, the present invention does not have specific (special) requirements to Zymolysis Equipment and condition, and the equipment and the condition of general fermentation plant all can be produced, and the production investment is less, and method is simple, and is with low cost, practical, easy and simple to handle, is easy to generally promote.
3, organic selenium content is higher in the selenium yeast product of the present invention, and quality is good, and its organic selenium content contains 500~1000 micrograms up to every gram fermentate, contains yeast viable count 2,000,000,000/g, crude protein content 35% in the product of the present invention simultaneously.This selenium yeast product safety is nontoxic, small investment, instant effect, high efficiency.
Description of drawings
Fig. 1 prepares the schematic flow sheet of selenium yeast for microbial fermentation of the present invention.
The specific embodiment
Below describe technology of the present invention and characteristics in detail by specific embodiment, but these embodiment are not in order to limit protection scope of the present invention.
The used bacterial classification of embodiment: used brewer's yeast (Saccharemycescerevisiae) bacterial classification is bought in China Committee for Culture Collection of Microorganisms common micro-organisms center in following examples of the present invention.Preserving number is: CGMCC AS2.2.
Embodiment 1
The selenium yeast for preparing present embodiment in accordance with the following methods, can be simultaneously referring to flow process shown in Figure 1:
One-level increases bacterium and cultivates: the brewer's yeast picking five rings on the test tube slant is seeded in 300ml brewer's wort enriched medium is housed (described brewer's wort enriched medium adds 1000ml distilled water by brewer's wort 130g, sugar degree regulation to 8 ripple woods, pH transfers to 6.0, sterilization was made in 20 minutes under 121 ℃ of temperature, measure 300ml) triangular flask in (triangular flask capacity 500ml), bottle stopper beyond the Great Wall, and wrap with sealing film, vibration was carried out one-level in 24 hours and is increased bacterium and cultivate under 30 ℃, 120 rev/mins conditions;
Secondary increases bacterium and cultivates: with the 50kg secondary seed medium (by corn flour 8 weight portions, wheat bran 2 weight portions, nutritive salt is (by potassium dihydrogen phosphate, ammonium sulfate, glucose mixed according to 1.5: 5: 1 and makes) 0.75 weight portion adds water 39.25 weight portions and mixes, pH transfers to 4.0,121 ℃ of sterilizations were made in 30 minutes) be heated to 60 ℃, add 8U enzyme AMS insulation hydrolysis alive 3 hours according to every gram starch in the culture medium, add the carbohydrase that the 140U enzyme is lived according to every gram starch in the culture medium then, keep 60 ℃ of saccharification 2 hours, be warming up to 120 ℃ of sterilizations 30 minutes afterwards, cool to again below 50 ℃, (Se content 43.806mg/ml) adds in this culture medium by a certain percentage with sodium selenite solution, make that selenium concentration reaches 25 μ g/ml in this culture medium, nutrient solution continues to be cooled to below 35 ℃, the saccharomyces cerevisiae liquid 5kg that above-mentioned process one-level is increased the bacterium cultivation is inoculated in this secondary medium, is 30 ℃ in temperature, stir culture was carried out secondary in 24 hours and is increased the bacterium cultivation under 130 rev/mins of conditions;
Solid state fermentation: increase bacterium liquid 50kg that bacterium cultivates and water (in advance with inorganic acid or organic acid HCl for example through secondary with above-mentioned, citric acids etc. are regulated pH to 6.0) 250kg, feed fermentation substrate (corn flour 325kg, cotton dregs 50kg, dregs of beans 50kg, rape dregs of rice 30kg, wheat bran 35kg, nutritive salt 7.5kg is (by potassium dihydrogen phosphate 1.5kg, ammonium sulfate 5kg, glucose 1kg mixes and makes), selenite 2.5kg mixes and makes, granularity be 3~8mm) 500kg with 1~2: 5~10: 10~20 weight ratio is evenly mixed, piling it high after mixing finishes is the trapezoidal heap of 20cm, simultaneously with floor heating 30 ℃ of condition bottom fermentations 72 hours, Tumble Dry after the fermentation ends, for reducing the destruction of bake out temperature to active component in the feed, the control temperature is about 45 ℃ in the described baking step, material after will drying is afterwards pulverized, preferred grinding particle size passes through 80 mesh sieves at least 75%, at least 95% by 40 mesh sieves, 100% by 20 mesh sieves, and pulverizing the back packing is finished product.
The present invention also provides the feed for preparing according to the method described above selenium yeast.This feed is used in the selenium yeast, organic selenium content 777 μ g/g, and the yeast viable count is up to 2,000,000,000/g, and crude protein content is up to 35%.
Embodiment 2
The selenium yeast for preparing present embodiment in accordance with the following methods:
One-level increases bacterium and cultivates: the brewer's yeast on the test tube slant is inoculated in the ratio of the about 60ml of every ring the brewer's wort enriched medium (distilled water that is added 7.5 times of volumes by brewer's wort is housed, sugar degree regulation to 6 ripple woods, pH transfers to 6.5, sterilization was made in 25 minutes under 120 ℃ of temperature) triangular flask in, bottle stopper beyond the Great Wall, and wrap with sealing film, vibration was carried out one-level in 24 hours and is increased bacterium and cultivate under 30 ℃, 120 rev/mins conditions;
Secondary increases bacterium and cultivates: with the 100kg secondary seed medium (by corn flour 18 weight portions, wheat bran 4 weight portions, nutritive salt is (by potassium dihydrogen phosphate, ammonium sulfate, glucose mixed according to 1.5: 5: 1 and makes) 1.5 weight portions add water 76.5 weight portions and mix, pH transfers to 4.5,121 ℃ of sterilizations were made in 30 minutes) be heated to 60 ℃, add 8U enzyme AMS insulation hydrolysis alive 2.5 hours according to every gram starch in the culture medium, add the carbohydrase that the 140U enzyme is lived according to every gram starch in the culture medium then, keep 60 ℃ of saccharification 2.5 hours, be warming up to 121 ℃ of sterilizations 20 minutes afterwards, cooling again, add sodium selenite solution (Se content 43.806mg/ml), make that selenium concentration reaches 20 μ g/ml in this culture medium, nutrient solution continues to be cooled to below 35 ℃, the saccharomyces cerevisiae liquid 10kg that above-mentioned process one-level is increased the bacterium cultivation is inoculated in this secondary medium, is 30 ℃ in temperature, stir culture was carried out secondary in 24 hours and is increased the bacterium cultivation under 150 rev/mins of conditions;
Solid state fermentation: increase bacterium liquid 100kg that bacterium cultivates and water 600kg (in advance with inorganic acid or organic acid HCl for example through secondary with above-mentioned, citric acids etc. are regulated pH to 6.5), feed fermentation substrate 1000kg is (by corn flour 60 weight portions, cotton dregs 10 weight portions, dregs of beans 10 weight portions, the rape dregs of rice 6 weight portions, wheat bran 7 weight portions, nutritive salt 1.5 weight portions, selenite 0.75 weight portion mixes to be made, sterilized 30 minutes for 121 ℃, granularity is 3~8mm) evenly mixing, piling it high after mixing finishes is the trapezoidal heap of 30cm, simultaneously with floor heating 45 ℃ of condition bottom fermentations 48 hours, Tumble Dry after the fermentation ends, 50 ℃ of bake out temperatures, material after will drying is afterwards pulverized, preferred grinding particle size passes through 80 mesh sieves at least 75%, at least 95% by 40 mesh sieves, 100% by 20 mesh sieves, pulverize the feed selenium yeast finished product that the back packing promptly gets present embodiment.
The feed selenium yeast that present embodiment makes.This feed is used in the selenium yeast, organic selenium content 682 micrograms/g, and more than yeast viable count 18.5 hundred million/g, crude protein content is up to 33.8%.
Embodiment 3
The selenium yeast for preparing present embodiment in accordance with the following methods:
One-level increases bacterium and cultivates: the brewer's yeast on the test tube slant is inoculated in the ratio of every ring 50ml the brewer's wort enriched medium (distilled water that is added 8 times of volumes by brewer's wort is housed, sugar degree regulation to 10 ripple woods, pH transfers to 6.0, sterilization was made in 20 minutes under 121 ℃ of temperature) triangular flask in, bottle stopper beyond the Great Wall, and wrap with sealing film, vibration was carried out one-level in 28 hours and is increased bacterium and cultivate under 30 ℃, 150 rev/mins conditions;
Secondary increases bacterium and cultivates: with the 50kg secondary seed medium (by corn flour 15 weight portions, wheat bran 5 weight portions, nutritive salt is (by potassium dihydrogen phosphate, ammonium sulfate, glucose mixed according to 1.5: 5: 1 and makes) 1.5 weight portions add water 78.5 weight portions and mix, pH transfers to 4.0,121 ℃ of sterilizations were made in 20 minutes) be heated to 55 ℃, add 8U enzyme AMS insulation hydrolysis alive 2.5 hours according to every gram starch in the culture medium, add the carbohydrase that the 140U enzyme is lived according to every gram starch in the culture medium then, keep about 2 hours of 55 ℃ of saccharification, be warming up to 121 ℃ of sterilizations 20 minutes afterwards, cooling again, add sodium selenite solution (Se content 43.806mg/ml), make that selenium concentration reaches 25 μ g/ml in this culture medium, nutrient solution continues to be cooled to below 35 ℃, the about 5kg of saccharomyces cerevisiae liquid that above-mentioned process one-level is increased the bacterium cultivation is inoculated in this secondary medium, is 30 ℃ in temperature, stir culture was carried out secondary in 24 hours and is increased the bacterium cultivation under 150 rev/mins of conditions;
Solid state fermentation: increase the about 55kg of bacterium liquid that bacterium cultivates and water 330kg (in advance with inorganic acid or organic acid HCl for example through secondary with above-mentioned, citric acids etc. are regulated pH to 6.0), feed fermentation substrate 820kg is (by corn flour 60 weight portions, cotton dregs 10 weight portions, dregs of beans 8 weight portions, the rape dregs of rice 6 weight portions, wheat bran 8 weight portions, nutritive salt 1.2 weight portions, selenite 0.8 weight portion mixes to be made, granularity is 3~8mm, sterilized 30 minutes for 121 ℃) evenly mix, piling it high after mixing finishes is the trapezoidal heap of 20cm, simultaneously with floor heating 40 ℃ of condition bottom fermentations 72 hours, Tumble Dry after the fermentation ends, 40 ℃ of bake out temperatures, material after will drying is afterwards pulverized, preferred grinding particle size passes through 80 mesh sieves at least 75%, at least 95% by 40 mesh sieves, 100% by 20 mesh sieves, pulverize the feed selenium yeast finished product that the back packing promptly gets present embodiment.
The feed selenium yeast that present embodiment makes.This feed is used in the selenium yeast, organic selenium content 880 micrograms/g, and the yeast viable count is up to more than about 23.2 hundred million/g, and crude protein content is up to 37.6%.