JP2515080B2 - Liquid-type fermentation method using ultrasonic waves - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fermentation method in a bread manufacturing process, and more particularly to a liquid type fermentation method using ultrasonic waves in a bread manufacturing process using a liquid type.

[0002]

2. Description of the Related Art In a fermentation process, which is one of the processes for producing breads, carbon dioxide and ethanol are produced by fermentation of sugars by yeast, and organic acids are produced. Then, the quality of fermentation in the baking process has a great influence on the quality of baked breads. Therefore, as a bread-making method capable of obtaining a stable fermentation state, there is a liquid seed method from the past. In this method, a fermentation liquor composed of sugars, yeast and water is prepared and used as bread seeds. That is, since a liquid containing no flour is fermented, there is an advantage that fermentation conditions can be easily controlled.

[0003]

However, even in this liquid type method, the fermentation step usually requires about 3 hours to 5 hours, which is the most time-consuming process in the bread making process. Has a great influence on the process time of the entire bread making process. Therefore, how to shorten the fermentation process is one of the problems in the liquid type method. Therefore, the inventors have noted that ultrasonic waves have physicochemical effects such as redox, protein denaturation, polymer depolymerization, emulsification, acceleration of reaction rate and diffusion rate. Then, as described below, shortening the fermentation time of the liquid species by using ultrasonic waves was examined, and the present invention was established.

[0004]

That is, according to the present invention,
As a means for solving the above technical problems, it is a fermentation method of a liquid seed stock solution used in the production of bread, saccharides, yeast and water by irradiating the liquid seed stock solution with ultrasonic waves. We have developed a liquid-type fermentation method using ultrasonic waves that is characterized by promoting fermentation.

The above-mentioned yeasts are raw yeasts and dry yeasts containing baker's yeast which can be usually used, and these raw yeasts and dry yeasts are usually mixed with lactic acid bacteria.

The saccharide may be any saccharide that can be utilized directly or indirectly by the baker's yeast and lactic acid bacteria contained in the yeast, such as sucrose, glucose and fructose. Further, the liquid stock solution is composed of the yeast, the sugar and water, but in addition, an antifoaming agent such as a surfactant or a salt, a buffer, a fermentation aid such as a nitrogen source, etc. may be included. You can also

The frequency and intensity of the ultrasonic waves are not particularly limited as long as they can promote fermentation by yeast or the like without destroying the yeast or lactic acid bacteria.

As fermentation conditions, usual fermentation conditions using liquid species, that is, fermentation temperature, fermentation time, pH and the like can be applied. The method of ultrasonic wave irradiation may be direct or indirect irradiation so that the ultrasonic wave reaches the liquid stock solution during fermentation.

[0009]

According to the above method, by irradiating the liquid stock solution with ultrasonic waves to perform fermentation, the fermentation by yeast or the like is activated in a short time and the amount of the fermentation product is increased. The fermentation promoting action in the present invention is considered to be because ultrasonic waves promoted the membrane permeation of saccharides in the cells.

[0010]

【Example】

[Example 1] The content of the present invention will be specifically described below with reference to examples, but this is merely an example of the present invention and does not limit the scope of the present invention. FIG. 1 shows a fermentation apparatus 1 used in the present invention. This device 1
Is composed of a fermentation vessel 2 and an ultrasonic transducer 6.
The fermentation vessel 2 is composed of an acrylic resin cylindrical portion 3 and a disc-shaped lid 4. Further, a stainless plate 5 is fixed as the bottom of the cylindrical portion 3, and an ultrasonic wave having a piezoelectric vibrator (made of lead zirconate titanate (PZT)) that oscillates an ultrasonic wave is provided inside the stainless plate 5. Converter 6
Is installed. An oscillator (not shown) is connected to the piezoelectric vibrator, and by operating the oscillator, ultrasonic waves oscillated from the piezoelectric vibrator indirectly act on the raw material liquid in the fermentation container 2. It is configured.

The types of ultrasonic waves oscillated from the ultrasonic transducer 6 are as shown in Tables 1 and 2, and these ultrasonic waves can be appropriately selected and used.

[0012]

[Table 1] Ultrasonic frequency and average input power

[0013]

[Table 2] Ultrasonic frequency and ultrasonic intensity

Next, the liquid stock solution to be ultrasonically fermented will be described. Liquid stock solution is prepared by adding 10 g of raw yeast for bread making, 15 g of sucrose and an antifoaming agent to 150 ml of water (deionized water).
13 g is mixed and configured. In preparing this stock solution, ingredients other than raw yeast were added to 150 ml of water, and the fermentation vessel 2 was placed in a constant temperature water tank, and after reaching a certain temperature, the raw yeast was mixed and a plurality of pieces were inserted from above the vessel 2. It is prepared by stirring for 5 minutes at 300 rpm with a stirring rod equipped with a rotating blade. An antifoaming agent is added so that the state of irradiation of ultrasonic waves is not affected by the generation of foam by fermentation. In this example, silicone oil is added.

Immediately after the above-mentioned stirring for 5 minutes, the ultrasonic oscillating element 6 is energized, ultrasonic waves are oscillated, and fermentation by ultrasonic irradiation is started. As a result, ultrasonic waves are irradiated from the bottom of the fermentation container 2 to the liquid seed stock solution in which the raw yeast is uniformly mixed. At this time, the frequency and average input power of the ultrasonic waves used are 47 kHz and about 1 W (corresponding to the frequencies of 46.7 kHz and 0.95 W () in Table 1). In addition, this ultrasonic wave is measured by an oscilloscope and a sound pressure probe, and is about 10 mm from the bottom surface of the fermentation container 2.
It has been confirmed that sound waves disappear at the height of. Therefore, it is considered that the ultrasonic waves act only near the bottom. In this way, the stock solution is fermented in a constant temperature water bath at 30 ° C. for 3 hours while being continuously irradiated with ultrasonic waves. In addition, in order to compare the effect of ultrasonic waves on fermentation with conventional methods, various measurements were similarly performed on the liquid stock solution fermented according to the conditions of this example except that ultrasonic waves were irradiated, and comparative examples (Fig. 2 and (It is shown as a control in FIG. 3 and Tables 3 and 4).

A stock solution of liquid species during fermentation was sampled at regular intervals from the start of the fermentation, and the ethanol content and sugar content in the collected solution were measured by the methods described below. Further, the amount of carbon dioxide generated from the liquid species was also measured by a thermograph at regular intervals. Further, after the fermentation was completed, a sample was taken from the liquid stock solution and the organic acid content was measured. FIG. 2 shows a graph showing changes in the amount of carbon dioxide generated and the generation rate thereof with time, the total amount of carbon dioxide generated is shown in Table 3 (thick frame), and the amount of organic acid produced is shown in Table 4. Moreover, the time-dependent change of the amount of ethanol production is shown in FIG.

The method of measuring the carbon dioxide generation amount, the ethanol generation amount, the organic acid generation amount, and the sugar content measured for the liquid stock solution to be ultrasonically fermented is as follows. Carbon dioxide generation amount Carbon dioxide generated in the liquid seed stock solution fermented in the fermentation container and emitted from the liquid surface is collected through a glass tube or the like, and the generation amount is determined by a thermograph installed outside the fermentation container 2. To measure. Amount of ethanol produced A sample is collected from the liquid stock solution to be fermented in the fermentation vessel,
The ethanol content of this sample is measured using a gas chromatograph, and the amount of ethanol produced in the stock solution is calculated. Amount of organic acid produced In the fermentation vessel, cells were collected from the liquid stock solution after fermentation for 3 hours by centrifugation, and the organic acid content in the cells was measured by an isotachophoresis device. Calculate the amount of organic acid produced. Sugar content A sample is taken from the stock solution of the liquid species during fermentation in the fermentation container, and the content of various residual sugars is measured by a method using an enzyme for this sample.

[0018]

[Table 3]

[0019]

[Table 4] As is clear from the description in the thick frame of Table 3, the total amount of carbon dioxide generated in this example is about 14% higher than that in the comparative example. In addition, the generation rate also rapidly increases immediately after the start of fermentation in this example, the time required to reach a constant rate θ ₁ and the time θ _{2 at} which a decrease in the amount of carbon dioxide generated due to lack of residual sugar occurs, respectively, compared to the comparative example. Is 30 minutes faster. That is, compared with the comparative example, in this example, the fermentation time in the steady state in the liquid type stock solution is shifted to the side that is 30 minutes earlier as a whole, the fermentation is accelerated in a short time after the start of fermentation, and as a result, the fermentation is performed 30 minutes earlier. It will end. Therefore, the fermentation time as a whole is shortened.

As shown in FIG. 3, the amount of ethanol produced was not different from that of the comparative example in the early stage of fermentation, but the amount of ethanol produced in this example was slightly compared 3 hours or 5 hours after the start of fermentation. It exceeds the example. Furthermore, according to Table 4, the production amount of organic acid was higher than that of the comparative example for all organic acids except acetic acid after the completion of fermentation for 3 hours, and produced by aerobic fermentation. The decrease in the amount of acetic acid produced is considered to be that the fermentation of this example is performed more anaerobically than the comparative example, and it is recognized that the fermentation is promoted.

Regarding the sugar content, it was confirmed that the sugar consumption rate of this example was higher than that of the comparative example until about 1 hour after the start of fermentation. That is,
This indicates that the consumption of sugars by fermentation is promoted, and supports the fact that fermentation is promoted in ultrasonic fermentation.

When the temperature of the liquid stock solution during fermentation was measured, the temperature of the liquid stock solution of this example was about 1 ° compared to the comparative example.
An increase in the temperature of C was recognized. However, the optimum fermentation temperature of the yeast used in this example, that is, Saccharomyces cerevisiae, is around 30 ° C, and such a temperature difference does not affect various reactions in fermentation.

Further, ultrasonic waves other than those used in this example (see Table 1) were also subjected to ultrasonic fermentation under exactly the same conditions as in this example. It has been confirmed (see Tables 3 and 4). Further, it has been confirmed that the fermentation products tend to decrease as the frequency increases and the input power decreases, and the fermentation products increase as the frequency decreases and the input power increases.

[Example 2] Next, by actually producing bread using a liquid stock solution that has been ultrasonically fermented, how is the influence of ultrasonic fermentation exerted on the quality of the bread produced? It was confirmed. Table 5 shows the preparation of the liquid seed stock solution and the preparation of the dough to be mixed with the fermented liquid seed stock solution in this example. As fermentation conditions, ultrasonic waves had a frequency of about 47 kHz, average input power of about 1 W (corresponding to frequencies of 46.7 kHz and 0.95 W () in Table 1), and fermentation time was 2.5 hours. In addition, except that the dough shown in Table 5 is prepared by using the liquid stock solution prepared by fermenting the liquid stock solution shown in Table 5 without ultrasonic irradiation, and the fermentation time is usually 3 hours. Was prepared as a comparative example by making bread under the same conditions as above. The outline of the baking process of this example is shown in FIG. 2 for bread of this example and comparative example
Table 6 shows the results of quality evaluation by one panelist.

[0025]

[Table 5] Preparation of liquid stock solution and dough and blending ratio The amount of charge actually used is 3 kg, and the ratio shows the weight part for the charge.

[0026]

[Table 6] Results of quality evaluation test

As is clear from these results, the bread produced by using the ultrasonically fermented liquid type stock solution is almost the same as the comparative example in terms of appearance and internal phase, and the comparative example in terms of flavor. It was higher. That is, the fermentation time can be shortened by 30 minutes in the actual bread making process, and the appearance and the quality of the internal phase of the baked bread can be maintained despite the shortened fermentation time, while at the same time improving the flavor. It was found that the effect of can be obtained together. These are considered to be the effects of promoting fermentation in the ultrasonic fermentation of the liquid stock solution. It is considered that the effect of improving the flavor is due to ultrasonic irradiation in the liquid state before the dough is prepared, and that the flavor component of bread or its precursor is produced in the liquid stock solution or the fermentation described above. It is considered that the increase in the amount of the product is involved.

As described above, it has been confirmed that the ultrasonic irradiation of the liquid stock solution directly leads to the shortening of the bread making process and, at the same time, has the effect of improving the flavor of bread.

[0029] The liquid stock solutions in Examples 1 and 2 were ultrasonically fermented without adding flour.
The effect of ultrasonic waves on fermentation was confirmed using samples of these liquid stock solutions to which wheat flour was added and medium seeds called sponges as samples, through measurement of fermentation products and quality evaluation by bread-making tests. As a result, a slight fermentation promoting effect was confirmed from the quality evaluation in the case of the stock solution containing a small amount of wheat flour. However, in the case of the liquid type stock solution and the medium type in which the amount of wheat flour added was increased, almost no effect of promoting the fermentation by ultrasonic waves was observed.

[0030]

As described above, according to the present invention, it is possible to shorten the fermentation time of a liquid seed concentrate by irradiating ultrasonic waves during fermentation of the liquid seed concentrate to promote fermentation. It is possible to shorten the time required for the bread making process itself and improve the efficiency of process control.

[Brief description of drawings]

FIG. 1 is a front view of a fermentation device used for fermenting a liquid seed stock solution.

FIG. 2 is a graph showing changes over time in the amount and rate of generation of carbon dioxide.

FIG. 3 is a graph showing changes in ethanol concentration over time.

FIG. 4 is a process diagram showing an outline of a bread making process using a liquid type.

Front Page Continuation (72) Inventor Takashi Ihara, Furo-cho, Chikusa-ku, Nagoya, Aichi Nagoya University Faculty of Engineering (72) Inventor, Hitoki Matsuda, Furo-cho, Chikusa-ku, Nagoya, Aichi Prefecture Nagoya University (72) Inventor Norio Arai, Faculty of Engineering, Nagoya University, Chirobe-ku, Aichi Prefecture Nagoya University (72) Inventor Masanobu Kashiya, Nagoya University, Faculty of Engineering, Furo-cho, Chikusa-ku, Nagoya City, Aichi Prefecture

Claims (1)

(57) [Claims] 1. A method for fermenting a liquid seed stock solution used for the production of breads, which comprises accelerating the fermentation of the sugar seeds by irradiating ultrasonic waves to the liquid seed stock solution consisting of sugar, yeast and water. Liquid fermentation using ultrasonic waves.