Saccharomyces cerevisiae FOSU-QQT as well as screening method and application thereof

Abstract

The invention discloses saccharomyces cerevisiae FOSU-QQT as well as a screening method and application thereof, and belongs to the field of microbe application. The saccharomyces cerevisiae FOSU-QQT screened and cultured by the invention does not have hemolytic activity, is gamma hemolysis and has inhibition effects on escherichia coli, salmonella, listeria monocytogenes and staphylococcus aureus, and a strain is prepared into direct vat set freeze-dried powder, so that industrial production is facilitated; saccharomyces cerevisiae FOSU-QQT with strong aroma production is added to brewing of the pineapple peel pomace fruit wine, the aroma production flavor can be obviously improved, the pineapple peel pomace fruit wine has the properties of acid resistance, SO2 resistance, ethanol resistance and the like, and the effect of improving the aroma of the composite fruit wine is facilitated; meanwhile, the saccharomyces cerevisiae FOSU-QQT can also be used for extracting a large amount of nutrient substances in the pineapple peel pomace by a compound fermentation technology with other strains, so that the quality of the fruit wine is improved.

Description

Technical Field

[0001] The present invention relates to the field of microbial technology, and in particular to a brewer's yeast FOSU-QQT and a screening method and application thereof. Background Art

[0002] Brewing yeast has a decisive influence on the quality of pineapple peel residue wine. During the fermentation process, yeast converts sugar into ethanol, carbon dioxide and other secondary metabolites, which together shape the chemical properties of the wine. Pineapple peel residue is rich in essential nutrients, including calcium, potassium, vitamin C, carbohydrates, dietary fiber and water, which are beneficial to the digestive system, weight management and overall balanced nutrition; it is rich in sugars such as sucrose, glucose and fructose, and citric acid as the main organic acid, which has health functions such as anti-oxidation, regulating blood circulation, and promoting digestion. Drinking fruit wine in moderation can help reduce the risk of cardiovascular and cerebrovascular diseases and help improve sleep quality. Brewing yeast is a superior raw material for brewing.

[0003] Aroma is one of the main factors affecting the quality of pineapple peel residue wine. The aroma of pineapple peel is mainly contributed by free and glycoside-bound aroma compounds, among which the glycoside-bound form can be converted into the free form during storage and processing, thereby enhancing the overall aroma characteristics. The peel also contains bromelain, a proteolytic enzyme known for its digestive properties. A series of biochemical reactions occur through the action of yeast and enzymes, which can be converted into aroma compounds, thereby enhancing the aroma of the wine. The quality and flavor of wine produced by brewing yeast in different fermentation raw materials and fermentation processes will be different. However, the quality of fruit wine produced by pineapple peel residue wine is not high and the existing fermentation agent is not acid-resistant. The pineapple peel residue wine brewed has problems such as weak aroma and lack of typical characteristics. Therefore, it is necessary to breed aroma-producing yeast suitable for brewing pineapple peel residue wine. In addition, due to the traditional natural fermentation, the microbial population is complex and the microbial metabolism is slow, which will also lead to the decline of the quality of pineapple peel residue wine. Summary of the invention

[0004] Based on this, in order to solve the technical problems of low quality and poor aroma effect of brewed fruit wine in the prior art, the present invention provides a brewer's yeast FOSU-QQT and a screening method and application thereof, and the specific technical scheme is as follows:

[0005] A brewer's yeast FOSU-QQT, the brewer's yeast (Saccharomyces cerevisiae) strain FOSU-QQT has been deposited in Guangdong Provincial Microbiological Culture Collection Center on September 19, 2024, with a deposit number of GDMCC NO: 65144.

[0006] The invention provides a screening method for brewer's yeast FOSU-QQT. The screening method comprises the following steps: separating yeast from naturally fermented pineapple peel residue, facultatively anaerobic culturing for 24 to 48 hours under the conditions of 28 DEG C and pH 3.8, then spreading and streaking the yeast on a YPD plate, selecting a single colony for screening to obtain a yeast strain with a strong aroma-producing ability, and identifying the yeast strain as brewer's yeast FOSU-QQT.

[0007] The invention discloses application of brewer's yeast FOSU-QQT with the deposit number of GDMCC NO: 65144 in brewing fruit wine.

[0008] Furthermore, the fruit wine comprises pineapple peel residue fruit wine.

[0009] The invention also provides a starter for brewing pineapple peel residue wine, which comprises brewer's yeast FOSU-QQT with a preservation number of GDMCC NO: 65144.

[0010] Furthermore, the method for preparing the fermentation agent includes: after collecting the brewer's yeast FOSU-QQT, further comprising the step of activating the brewer's yeast FOSU-QQT; or the step of resuspending the brewer's yeast FOSU-QQT to prepare a bacterial suspension; or further comprising the step of mixing the brewer's yeast FOSU-QQT with a freeze-drying protective agent and preparing a freeze-dried powder by freeze-drying.

[0011] Another aspect of the present invention provides a pineapple peel residue fruit wine, the raw materials of which include: brewer's yeast FOSU-QQT with a preservation number of GDMCC NO: 65144 and pineapple peel residue.

[0012] Furthermore, the alcohol content of the fruit wine is 5% vol to 10% vol.

[0013] Furthermore, the brewing method of the pineapple peel residue wine is as follows: adding brewer's yeast FOSU-QQT with a preservation number of GDMCC NO: 65144 as a strain to the pretreated pineapple peel residue for fermentation, and separating the wine when the sugar content is ≤10g / L.

[0014] Furthermore, the pretreatment is: crushing the pineapple peel residue and treating it in carbon dioxide at 15°C to 20°C for 1d to 3d.

[0015] Compared with the prior art, the present invention has the following beneficial effects:

[0016] 1. The brewer's yeast FOSU-QQT screened and cultured by the present invention has no hemolytic activity, is γ-hemolytic, has inhibitory effects on Escherichia coli, Salmonella, Listeria monocytogenes and Staphylococcus aureus, and the strain is made into a direct-throw freeze-dried powder, which is convenient for industrial production; the brewer's yeast FOSU-QQT with strong aroma production is added to the brewing of pineapple peel residue fruit wine, which can significantly increase the aroma flavor, and has the properties of acid resistance, SO2 resistance, ethanol resistance and the like, which is beneficial to improving the aroma of the composite fruit wine; at the same time, the brewer's yeast FOSU-QQT can also use a composite fermentation technology with other strains to extract a large amount of nutrients from the pineapple peel residue, thereby improving the quality of the fruit wine.

[0017] 2. During the brewing process of the pineapple peel residue fruit wine of the present invention, nutrients are greatly retained, the pineapple flavor is retained, and the aroma and smell of the pineapple itself are maintained. Under the flavoring effect of brewer's yeast FOSU-QQT, the fruit wine is given a better sensory experience, and not only the flavor and taste are good, but also the fruit wine has a higher nutritional value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The present invention can be further understood from the following description in conjunction with the accompanying drawings. The components in the figures are not necessarily drawn to scale, but the emphasis is placed on illustrating the principles of the embodiments. In different views, the same reference numerals designate corresponding parts.

[0019] Figure 1 Schematic diagram of microscopic examination of strains screened in Example 1;

[0020] Figure 2 Schematic diagram of picking single colonies for streaking;

[0021] Figure 3 This is a schematic diagram of the ultra-fast gas phase electronic nose detecting the proportion of yeast components;

[0022] Figure 4 Schematic diagram of the acid resistance of different strains;

[0023] Figure 5 Schematic diagram of SO2 resistance of different strains;

[0024] Figure 6 Schematic diagram of the sugar tolerance of different strains;

[0025] Figure 7 Schematic diagram of ethanol tolerance of different strains;

[0026] Figure 8 Schematic diagram of ITS sequencing of strain Saccharomyces cerevisiae FOSU-QQT;

[0027] Fig. 9 Schematic diagram of the hemolytic activity experiment of Saccharomyces cerevisiae FOSU-QQT;

[0028] Fig.10 Schematic diagram of the component ratios of pineapple peel residue wine brewed with brewer's yeast FOSU-QQT. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with its embodiments. It should be understood that the specific implementation methods described herein are only used to explain the present invention and do not limit the scope of protection of the present invention.

[0030] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0031] A brewer's yeast FOSU-QQT in one embodiment of the present invention, the brewer's yeast (Saccharomyces cerevisiae) strain FOSU-QQT, has been deposited in Guangdong Provincial Microbiological Culture Collection Center on September 19, 2024, with a deposit number of GDMCC NO: 65144.

[0032] In one of the embodiments, the present invention provides a screening method for brewer's yeast FOSU-QQT, the screening method comprising: isolating yeast from naturally fermented pineapple peel residue, facultatively anaerobic culturing for 24 h to 48 h at 28° C. and pH 3.8, then spreading and streaking the yeast on a YPD plate, selecting a single colony for screening to obtain a yeast strain with a strong aroma-producing ability, which is identified as brewer's yeast FOSU-QQT.

[0033] In one embodiment, the present invention provides an application of the brewer's yeast FOSU-QQT with the deposit number of GDMCC NO: 65144 in brewing fruit wine.

[0034] In one embodiment, the fruit wine comprises pineapple peel residue wine.

[0035] In one embodiment, the present invention further provides a starter for brewing pineapple peel residue wine, which includes brewer's yeast FOSU-QQT with a preservation number of GDMCC NO: 65144.

[0036] In one embodiment, the method for preparing the fermentation agent is: after collecting the brewer's yeast FOSU-QQT, it also includes the step of activating the brewer's yeast FOSU-QQT; or the step of resuspending the brewer's yeast FOSU-QQT to prepare a bacterial suspension; or it also includes the step of mixing the brewer's yeast FOSU-QQT with a lyophilization protectant and preparing a lyophilized powder by lyophilization.

[0037] In one embodiment, the lyophilized powder uses defatted powder as a protective agent.

[0038] In one embodiment, the freeze-dried powder is prepared as follows: skim milk powder is prepared into a 5% skim milk powder solution, centrifuged at 8000r / min for 30min, the supernatant is removed to obtain bacterial sludge, the skim milk powder solution and the bacterial sludge of Saccharomyces cerevisiae FOSU-QQT are mixed in a volume ratio of 3:1, pre-frozen at -20°C for 4h, and freeze-dried using a freeze dryer.

[0039] In one embodiment, the present invention provides a pineapple peel residue fruit wine, the raw materials of which include: brewer's yeast FOSU-QQT with a preservation number of GDMCC NO: 65144 and pineapple peel residue.

[0040] In one embodiment, the brewer's yeast FOSU-QQT with the deposit number of GDMCC NO: 65144 can also be compounded with other strains and applied to the brewing of pineapple peel residue wine.

[0041] In one embodiment, the alcohol content of the fruit wine is 5% vol to 10% vol.

[0042] In one embodiment, the brewing method of the pineapple peel residue wine is: adding the brewer's yeast FOSU-QQT with a preservation number of GDMCC NO: 65144 as a strain to the pretreated pineapple peel residue for fermentation, and separating the wine when the sugar content is ≤10g / L.

[0043] In one embodiment, the pretreatment is: crushing the pineapple peel residue and treating it in carbon dioxide at 15° C. to 20° C. for 1 to 3 days.

[0044] In one embodiment, the lyophilized powder is diluted to a bacterial solution concentration of 1×10 6 -10 9 CFU / mL, and after dilution, it was evenly added into the pineapple peel residue wine brewing and fermented at room temperature.

[0045] The brewer's yeast FOSU-QQT screened and cultured in the above scheme has no hemolytic activity, is γ-hemolytic, has inhibitory effects on Escherichia coli, Salmonella, Listeria monocytogenes, and Staphylococcus aureus, and the strain is made into a direct-throw freeze-dried powder, which is convenient for industrial production; the brewer's yeast FOSU-QQT with strong aroma production is added to the brewing of pineapple peel residue fruit wine, which can significantly increase the aroma and flavor, and has the properties of acid resistance, SO2 resistance, ethanol resistance, etc., which is beneficial to improving the aroma of the complex fruit wine.

[0046] The embodiments of the present invention will be described in detail below with reference to specific examples.

[0047] Embodiment 1:

[0048] A screening method for brewer's yeast FOSU-QQT, the screening method comprising: isolating yeast from naturally fermented pineapple peel residue, facultatively anaerobic culturing for 24 hours at 28°C and pH 3.8, then spreading and streaking on a YPD plate, and preliminarily screening strains with yeast morphology after electronic microbiological microscopy; screening strains with higher aroma production scores by calculating scores through an olfactory method; detecting strains with stronger aroma production through an ultra-fast gas phase electronic nose, and isolating yeast strains with a large proportion of aroma production components; determining the indexes of acid tolerance, SO2 tolerance, sugar tolerance, and ethanol tolerance growth curves of the yeast strains isolated in the previous step; screening the best strain based on the above indexes, and performing ITS sequencing to identify the strains;

[0049] like Figure 1 As shown, the strain is milky white, shiny, round or oval in shape, with a smooth surface, easy to pick up, sticky, and neat edges after microscopic examination.

[0050] like Figure 2 As shown, a schematic diagram of further streaking and selecting single colonies was used, and yeast strains with stronger aroma production were screened using olfaction and ultra-fast gas phase electronic nose detection. The results are shown in Table 1 below.

[0051] Table 1: Weighted scoring results of aroma-producing yeasts by olfactory method

[0052]

[0053] like Figure 3 As shown, the schematic diagram of the proportion of yeast components detected by ultra-fast gas phase electronic nose is used. The ultra-fast gas phase electronic nose is used to screen yeast strains with strong aroma-producing ability. Esters, terpenes, aldehydes, ketones, acids, alcohols, etc. ferment rich fruity and floral aromas to produce wine aromas with different flavors.

[0054] like Figure 4 As shown, Figure 4Schematic diagram of the acid resistance of different strains, for screening strains with good acid resistance.

[0055] like Figure 5 As shown, Figure 5 This is a schematic diagram of the SO2 resistance of different strains. Further screening of strains with good SO2 resistance is carried out. Adding an appropriate amount of SO2 can kill or inhibit the growth of harmful microorganisms in fruit wine, prevent the fruit wine from becoming sour, and play a certain role in protecting the color.

[0056] like Figure 6 As shown, Figure 6 This is a schematic diagram of the sugar tolerance of different strains, for further screening of strains with good sugar tolerance.

[0057] like Figure 7 As shown, Figure 7 This is a schematic diagram of the ethanol resistance of different strains, for further screening of strains with good ethanol resistance.

[0058] The strains finally screened were subjected to ITS sequencing, such as Figure 8 As shown, Figure 8 This is a schematic diagram of ITS sequencing of the strain Saccharomycescerevisiae FOSU-QQT; the strain was determined to be Saccharomyces cerevisiae (brewer's yeast), and was named Saccharomyces cerevisiae FOSU-QQT (brewer's yeast FOSU-QQT), and was handed over to Guangdong Provincial Microbiological Culture Collection Center for preservation, with a preservation date of September 19, 2024, and a strain collection number of GDMCCNO.65144.

[0059] The strain Saccharomyces cerevisiae FOSU-QQT was subjected to a hemolytic activity test. Fig. 9 As shown, Fig. 9 Schematic diagram of the hemolytic activity experiment of Saccharomyces cerevisiae FOSU-QQT. Fig. 9 It can be seen that it is γ-hemolytic and has no hemolytic activity; it has inhibitory effects on Escherichia coli, Salmonella, Listeria monocytogenes and Staphylococcus aureus.

[0060] Therefore, it has been identified that the strain does not have hemolytic activity, but is γ-hemolytic, and has inhibitory effects on Escherichia coli, Salmonella, Listeria monocytogenes, and Staphylococcus aureus. The strain is made into direct-injection freeze-dried powder to facilitate industrial production; the brewing yeast with strong aroma is added to the pineapple peel residue wine to increase the aroma and flavor; the composite fermentation technology of yeast and other strains can also be used to extract a large amount of nutrients from the pineapple peel residue to improve the quality of the wine.

[0061] Embodiment 2:

[0062] Activation of strains: The fermented Saccharomyces cerevisiae FOSU-QQT was streaked on a YPD solid plate and cultured at 28°C under facultative anaerobic conditions for 24 h. After secondary activation, it was inoculated on a YPD liquid medium and diluted and counted. The bacterial solution concentration was adjusted to 1×10 10 CFU / mL.

[0063] Embodiment 3:

[0064] Preparation of lyophilized powder: centrifuge the bacterial suspension at 8000r / min at 4°C for 15min, discard the supernatant, collect the bacterial mud at the bottom of the centrifuge tube, wash twice with 0.90% sterile PBS buffer, resuspend under the same conditions for 1min, add sterilized skim milk powder at a mass ratio of 1:4, resuspend and mix, pre-freeze at -20°C for 4h, put into a freeze dryer for 30h to make lyophilized powder, and preserve the strain in the form of lyophilized powder.

[0065] Accurately weigh a certain weight of freeze-dried powder, dissolve it in a certain proportion of sterile water under sterile conditions, and dilute it to 1×10 6 -10 9 CFU / mL. Calculate the number of viable bacteria per gram of lyophilized powder based on the colony count.

[0066] Embodiment 4:

[0067] The pineapple peel residue is crushed and treated in carbon dioxide at 20° C. for 2 days to obtain pretreated pineapple peel residue;

[0068] The diluted freeze-dried powder is added to the pre-treated pineapple peel residue for room temperature fermentation, and the wine is separated when the sugar content is ≤10g / L.

[0069] In the same way, the strain Saccharomyces cerevisiae 2.137 was used to ferment pineapple peel residue at room temperature.

[0070] The strains Saccharomyces cerevisiae 2.137, Saccharomyces cerevisiae FOSU-QQT and CK were compared with each other, and the results are shown in Tables 2 to 4 below.

[0071] Table 2: GC-MS analysis results of aroma components of pineapple peel residue wine from Saccharomyces cerevisiae 2.137

[0072]

[0073] Table 3: GC-MS analysis results of aroma components of pineapple peel wine produced by Saccharomyces cerevisiae FOSU-QQT group

[0074]

[0075]

[0076] Table 4: GC-MS analysis results of aroma components of pineapple peel residue wine in group CK

[0077]

[0078]

[0079] As can be seen from Tables 2 to 4, the main aroma components of fruit wine are esters, such as ethyl acetate, ethyl octanoate, ethyl caproate, ethyl caprate, ethyl n-hexanoate, isoamyl acetate, etc. Saccharomyces cerevisiae FOSU-QQT has a significant aroma-producing and aroma-enhancing effect on brewing pineapple peel residue fruit wine. Fig.10 Schematic diagram of the composition ratio of pineapple peel residue wine brewed by brewer's yeast FOSU-QQT. Fig.10 It can also be shown that the brewer's yeast FOSU-QQT screened in this application has a significant aroma-enhancing effect.

[0080] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A cerevisiae yeast FOSU-QQT, characterized in that The Saccharomyces cerevisiae strain FOSU-QQT was deposited in the Guangdong Provincial Microbiological Culture Collection Center on September 19, 2024, with the deposit number GDMCCNO: 65144.

2. A screening method for Saccharomyces cerevisiae FOSU-QQT, characterized in that: The screening method comprises the following steps: isolating yeast from naturally fermented pineapple peel residue, facultatively anaerobic culturing for 24 to 48 hours at 28° C. and pH 3.8, then spreading and streaking the yeast on a YPD plate, selecting a single colony for screening to obtain a yeast strain with a strong aroma-producing ability, and the yeast strain was identified as Saccharomyces cerevisiae FOSU-QQT.

3. Application of brewer's yeast FOSU-QQT with a deposit number of GDMCC NO: 65144 in brewing fruit wine.

4. The use according to claim 3, characterized in that: The fruit wine comprises pineapple peel residue fruit wine.

5. A starter for brewing pineapple peel residue wine, characterized in that: The deposit number of the yeast is GDMCC NO:65144.

6. The leavening agent according to claim 5, characterized in that The method for preparing the fermentation agent comprises: after collecting the brewer's yeast FOSU-QQT, further comprising the step of activating the brewer's yeast FOSU-QQT; or the step of resuspending the brewer's yeast FOSU-QQT to prepare a bacterial suspension; or further comprising the step of mixing the brewer's yeast FOSU-QQT with a freeze-drying protective agent and preparing a freeze-dried powder by freeze-drying.

7. A pineapple peel residue wine, characterized in that: The raw materials include: brewer's yeast FOSU-QQT with a preservation number of GDMCCNO: 65144 and pineapple peel residue.

8. The pineapple peel residue wine according to claim 7, characterized in that: The alcohol content of the fruit wine is 5% vol to 10% vol.

9. The pineapple peel residue wine according to claim 8, characterized in that: The brewing method of the pineapple peel residue wine comprises the following steps: adding FOSU-QQT, a brewer's yeast with a preservation number of GDMCC NO: 65144, as a strain to the pretreated pineapple peel residue for fermentation, and separating the wine when the sugar content is ≤10 g / L.

10. The pineapple peel residue wine according to claim 9, characterized in that: The pretreatment comprises: crushing the pineapple peel residue and treating it in carbon dioxide at 15° C. to 20° C. for 1 to 3 days.

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