JPS61169742A - Method and apparatus for measuring coagulation state of cheese curd - Google Patents

Abstract

PURPOSE:To enable accurate measurement of the coagulation state of a cheese curd, by arranging a sensing unit for the injection of a sample of a natural cheese material between a vibration generating side disc and a pressure receiving side diaphragm to convert changes in the pressure based on the amplitude of the diaphragm into an electrical signal for recording with the application of a fixed vibration to the sample. CONSTITUTION:A vibration generating side disc 2 and a pressure receiving side diaphragm are attached to a sensing unit 1 thereoutside separately. The sending unit is set successively to a preparation tank for natural cheese material and a sample of cheese material is picked out and injected into the sensing unit to record and measured the coagulation state of the sample according to the above-mentioned procedure. With such an arrangement, it is possible to judge an appropriate cutting timing of a cheese curd in comparison of the recorded value with the preset value of amplitude of the output voltage for the timing which is suited to the cutting of the cheese curd based on the amplitude value corresponding to changes in the pressure sensed with the diaphragm following the coagulation of the sample taken from a cheese material tank.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for accurately measuring the coagulation state of cheese curd in order to determine the appropriate time to cut the cheese curd, and a measuring device therefor.

Obedience! Sou U ■ 11 Higashi In the production of natural cheese, coagulation of natural cheese raw materials after adding rennet and starter to raw milk (
The curd production process takes various steps depending on the quality of the milk used as raw materials, the activity of the starter and rennet, the temperature, etc. Therefore, it is not easy to judge when to cut the curd produced by coagulation. Conventionally, cutting has been carried out based on sensual judgment by a skilled person. However, in sensory evaluation, it is inevitable that the hardness of the cards will vary to some extent.

In recent years, as manufacturing equipment has become larger, it has become necessary to form curds with stable structures and improve manufacturing yields. Providing a measuring device for this purpose has become an important issue in natural cheese production.

In the past, measurement devices that applied optical and acoustic means have been proposed in response to the above issues, but all of them are laboratory scale and have not yet been usable on factory production lines. It's so hot.

Recently, a method of measuring mechanical vibration has been proposed to measure gel hardness.This method involves placing a sample between vibrating disks placed opposite each other, and measuring the vibration transmission of the sample. How to (Dairy & Ice Cream Fie)
ld, 161(8) 68F-688, 1978),
A method of vibrating a cylindrical container containing a gel-like food and measuring its attenuation rate (J, Food Sci, 45 (2)
) 204-207.1980; Journal of Japan Food Industry Association, 27(5) 227-233.1980), but it has not yet been put to practical use in production lines.

The day? In view of the above-mentioned situation, the inventor of the present invention investigated the measurement of the coagulation state of cheese curd, and as a result, the inventor decided to apply constant vibration using an oscillator to a sample of natural cheese raw material to which rennet and starter were added. When sensing this with a highly sensitive diaphragm, when the sample is still in a liquid state, the vibrations are diffused upward and transmitted directly to the diaphragm, but as the sample gels, the vibrations are transmitted upward. The present invention was made based on the knowledge that the diffusion becomes smaller and is directly transmitted to the diaphragm, that is, the coagulation change of the sample can be determined by the change in the amplitude that is directly transmitted to the diaphragm.

Therefore, an object of the present invention is to arrange a sensing unit for injecting a sample of natural cheese raw material between a vibration-generating side disk and a pressure-receiving side diaphragm, and apply a constant vibration to the sample to increase the amplitude in the diaphragm. By converting and recording the pressure changes caused by
It is an object of the present invention to provide a method for accurately measuring the coagulation state of cheese curd and a measuring device therefor, which can be directly applied to a factory line.

The present invention will be explained in detail below.

Inject a sample of natural cheese raw material into the sensing unit and maintain its temperature and liquid level at a constant level.
A constant vibration from an oscillator is applied to the sensing unit via a vibration-generating disk attached to the unit, and the vibration is transmitted to the sample in the unit, and the transmitted vibration is transmitted to a vibration-generating disk opposite to the vibration-generating disk. The temperature is sensed by a diaphragm attached to the unit, the pressure change resulting from this sensing is converted into an electrical signal by a transducer, this converted signal is then amplified and recorded, and the solidification state of the cheese curd is determined from the amplitude of the wavy curve. and (2) a sensing unit for injecting a sample of natural cheese raw material, which is equipped with a temperature sensor and a heater on the outer wall; an oscillator connected to the sensing unit via a vibration-generating disk; A transducer arranged in a sensing unit in series with a diaphragm in which the above-mentioned vibration-generating side discs are attached facing each other; an amplifier in series with the transducer; and a recording needle in series with the amplifier. There is a device for measuring.

The term "natural cheese raw material" as used herein means a milky raw material prepared for the production of cheese by adding rennet, a starter, and other blended raw materials.

The measuring device used in the present invention for answering questions will be explained based on the attached drawings that illustrate the measuring device, and the measuring method according to the present invention will also be explained.

FIG. 1 is an explanatory diagram of the present device, in which numeral 1 is a sensing unit for injecting a sample of natural cheese raw material, and a thin silicone rubber 3 is attached to one side of the sensing unit on the oscillation side. A plate 2 is attached, and a diaphragm 6 is mounted on the other side facing the disk 2 and 13+.
It is attached with a gap of wm.

An oscillator 4 is connected to the oscillation side disk 2. Note that 5 is a motor for operating the oscillator 4.

The diaphragm 6 is connected to a converter 7, the converter 7 is connected to an amplifier 8, and the amplifier is connected to a recording needle 9.

In the sensing unit l of this device, as described above, the vibration-generating side disc 2 and the pressure-receiving side diaphragm are attached so as to be disposed on the outside thereof, so 1. There is an advantage that there is no need to remove the diaphragm and clean the inside of the unit each time a measurement is made, unlike conventional sensing units in which opposing diaphragms are immersed inside. In addition, the sensing unit in this device is
The top and bottom are formed to allow smooth injection of the sample and discharge of gelled cheese from the cheese raw material tank.

Note that if the top of the sensing unit is widened as shown in the figure, the rise in the liquid level before gelation of the sample due to the vibration of the vibration generation side disk 2 will be reduced, and the amplitude value due to the vibration accompanying gelation will be reduced. This is convenient for observing the change process. Note that a temperature sensor and a heater are installed on the outer wall of the sensing unit (not shown).

In addition, in the apparatus according to the present invention, the vibration to be applied to the sample is generated by operating the oscillator 4, which is composed of a low-speed motor 5 and an eccentric cam, etc., and is performed via the disk 2, so that the vibration is stable and low frequency. Since the vibration is a constant change over the entire surface of the disk 2, the stroke is relatively small, and there is no fear that the gel formed by solidification of the sample will be destroyed.

In order to generate low-frequency emotions, a conventional method has been to use a pump to send liquid to and return from a diaphragm, but this method not only complicates the device, but also makes it difficult to send liquid. It tends to cause unevenness in the amount, so 1.
The disadvantage is that the displacement of the diaphragm lacks stability.

In this apparatus, the vibrations transmitted from the oscillator 4 to the sensing unit as described above are sensed by the diaphragm 6 attached to the sample in the unit. This diaphragm 6 is designed to have a waveform and a diameter of 110 s, so that it can directly sense vibrations that do not destroy the gel formed by solidification of the sample, and the distance from the vibration generating side disc is 13 m. - It is preferable to arrange it so that it becomes -.

In this device, a converter 4 is arranged in series with the diaphragm, and the converter converts the pressure change (slight differential pressure) caused by the vibration detected by the diaphragm into an electrical signal, which is then connected to the converter. The sample is amplified by an amplifier 8 and recorded by a recording needle 9 connected to the amplifier 8, so that the coagulation state of the sample can be determined from the amplitude of the wavy curve. Note that lO in the figure is a valve attached to the converter 7, and after the liquid level of the sample in the unit is stabilized,
This is to close the converter 7 to keep the negative side pressure of the converter 7 constant.

Next, a method of measuring the coagulation state of cheese curd using this device will be explained.

First, a cheese tank filled with natural cheese ingredients (
After injecting the sample into the sensing unit 1 from a container (not shown) and keeping the liquid level in the unit constant using an overflow method, the pulp attached to the converter 4 is closed.

The sample inside the unit is controlled to be kept at the same temperature as the natural cheese raw material inside the cheese tank using a temperature sensor and heater installed on the outside wall of the unit.

Next, the motor 5 is rotated at a low speed of 2 rpm, converted into reciprocating motion by an eccentric cam, and the vibration generating side disk 2 is vibrated twice per minute with a stroke of 0.25 mm. This vibration is transmitted to the sample within the sensing unit 1 via the stretchable thin silicone rubber 3. Due to this vibration transmission to the sample, when the sample is in a liquid state that has not yet gelled, the vibration is diffused above the sample, causing only a slight rise in the liquid level, and is not directly transmitted to the diaphragm, but when the sample gels. Accordingly, the upward diffusion of the vibration becomes smaller and is directly transmitted to the diaphragm 6, where it is sensed as a pressure change. The pressure change detected by the diaphragm is transferred to the transducer 7 (slight differential pressure).
This is converted into an electrical signal, which is amplified by an amplifier 8 and recorded by a recorder 9, and the solidification state of the cheese curd is determined from the amplitude of the recorded sinusoidal curve. Note that the recorder 9 is equipped with an alarm device so that it can sense the output from the diaphragm. The cheese curd formed by coagulation is removed from the bottom of the sensing unit.

Incidentally, FIG. 2 shows the relationship between the coagulation time of the cheese raw material and the amplitude of vibrations received by the diaphragm.

Figure 2 shows the above relationship as a change in the output voltage amplitude value. In the figure, AI indicates the amplitude due to the rise in the liquid level of the sample in the sensing unit, and A2 indicates the amplitude due to the vibration directly applied to the diaphragm. , At and A2 indicate their composite value.

Further, FIG. 3 shows the transition of the amplitude due to the rise in the liquid level of the sample to the increase in amplitude due to solidification.

As described above, the sensing unit in the apparatus according to the present invention is installed in series with the natural cheese raw material preparation tank, and a sample of the cheese raw material is extracted and injected into the sensing unit, and the above-mentioned procedure is carried out. The coagulation state of the sample can be recorded and measured according to the method. Therefore, based on the amplitude value of the pressure change (output voltage) sensed by the diaphragm as the sample collected from the cheese raw material tank solidifies, the amplitude value of the output voltage at the time suitable for cutting cheese curds is set in advance. By doing so, it becomes possible to determine the correct time to cut the cheese curd by comparing it with the above-mentioned recorded value. As described above, according to the present invention, it is possible to incorporate the present device into the cheese manufacturing process to automatically determine when to produce curd and when to cut the curd.

EXAMPLES The present invention and its effects will be explained in more detail with reference to Examples below.

Preparation of natural cheese raw material on the wafer: 0.1 wt glucono-δ-lactone (starter) added to reduced skim milk with a total solid content of 10 wt% and milk fat 0.1 wt%.
%, CaCl20.05wt% and rennet 0.01
wt% was added and blended.

Measurement of coagulation state: The above cheese raw material is placed in a cheese tank, and a sample of the cheese raw material is injected into the sensing unit of this device connected to it through the openable/closable opening of the tank. After making the liquid level of the sample in the unit constant, the pulp attached to the transducer is closed, the oscillator is activated, and the eccentric cam converts it into a reciprocating motion, causing the vibration-generating side disc to move twice per minute at 0.25 mm. It was vibrated with the stroke of. The temperature of the sample inside the unit is kept at the same temperature as the cheese raw material inside the tank (30°C) during the operation period using an electric heater and temperature sensor installed on the outer wall of the unit.
℃).

Vibration from the oscillator is transmitted to the sample in the sensing unit via the vibration-generating disk, and this vibration is then directly sensed by the diaphragm as the sample solidifies, so the resulting pressure change is transferred to the transducer. convert it into an electrical signal,
This was amplified using an amplifier and recorded. As a result, the output voltage increased almost linearly for about 30 minutes from the start of solidification of the sample (so-called rise).

Next, the above operation was repeated five times, and the elapsed time was examined using the rise point of each sample and the output voltage values of 1.5V and 3V as check points. The results are shown in FIG.

As seen in FIG. 4, there is no essential difference in the elapsed time at each of the checkpoints, which indicates that the method according to the present invention has good reproducibility.

It was confirmed that the appropriate cutting time for the cheese curd produced by coagulation was around 1.5V.

Preparation of natural cheese raw material: To raw milk with a total solid content of 11 wt% and milk fat of 2.8 wt%, lactic acid bacteria starter control t%, CaCl2 o, ot trade% and rennet 0.003 wt% were added and blended. I used something.

Measurement of coagulation state: Using the above cheese raw material, the coagulation state was measured in the same manner as described in Example 1. This measurement was repeated five times. The cutting timing of cheese curd determined by this method was determined by a conventional sensory method, and the results are shown in FIG. Cutting based on the sensual method as seen in Figure 5.

Since the output voltage amplitude m value when performed by the method of the present invention is between 1.3 and 1.5V, the cutting time is determined at which the output voltage amplitude value by the method of the present invention is 1.5V. It can be seen that they are almost in agreement.

Incidentally, the difference (0.2V) between 1.3V and 1.5V is only a difference of about 2 minutes when converted into elapsed time.

The reason why the coagulation progress of the samples in FIG. 5 is different each time is because the activity of the starter in the samples used each time is not constant.

After the measurement is completed as described above, the cock provided at the bottom of the sensing unit is opened, the sample is taken out, warm water is injected to clean it, and the sample is used for the next production line.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram illustrating the apparatus according to the present invention, Fig. 2 shows the relationship between the solidification time of a sample of cheese raw material and the output voltage amplitude value, and Fig. 3 shows the relationship between the liquid level rise due to vibration of the sample. The reproducibility of the method of the invention is demonstrated by measuring the solidification elapsed time at specific checkpoints. FIG. 5 shows the results of comparing the cutting time of cheese curd determined by the method of the present invention with that determined by the sensory method.

Claims (2)

[Claims] (1) Inject a sample of natural cheese raw material into the sensing unit and maintain the temperature and liquid level constant.
A constant vibration from an oscillator is applied to the sensing unit via a vibration-generating disk attached to the unit, and the vibration is transmitted to the sample in the unit, and the transmitted vibration is transmitted to a vibration-generating disk opposite to the vibration-generating disk. The temperature is sensed by a diaphragm attached to the unit, the pressure change resulting from this sensing is converted into an electrical signal by a transducer, this converted signal is then amplified and recorded, and the solidification state of the cheese curd is determined from the amplitude of the wavy curve. A method for measuring the coagulation state of cheese curd, characterized by: (2) Sensing unit for injecting a sample of natural cheese raw material; An oscillator connected to the sensing unit via a vibration-generating side disk; Attached to the sensing unit opposite to the vibration-generating side disk A device for measuring the coagulation state of cheese curd, comprising: a transducer disposed in series with a diaphragm; an amplifier coupled with the transducer; and a recorder coupled with the amplifier.