JP2554010B2 - Freeze-dried porridge manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention can be used in the field of food processing and manufacturing, and more particularly to a method for manufacturing dried porridge.

[0002]

2. Description of the Related Art There are many retort and canned products in the market as instant porridge, but these products are subjected to pressure heat sterilization in the manufacturing process. However, there was a problem that the rice content was crushed and became a paste.

On the other hand, the dry type porridge does not change with time as described above, but has problems in terms of quality such as rice grain restorability and texture . That is, porridge is generally different from rice
It has a high viscosity and is difficult to restore when freeze-dried. This is α
The starch granules that have been converted to β are once dried by freezing and then dried.
It is considered that when the boiling water is poured, it becomes alpha again.
However, what is often seen in dry type rice porridge is that
Only the surface becomes alpha, and hot water penetrates into the solid porridge.
It is thought that the reason is that it is blocking . As a technique to solve these problems , especially regarding the pretreatment method and drying method ,
A conventional technique such as is proposed.

That is, the prior art 1 is, for example, Japanese Patent Publication No. Sho 58-
As described in Japanese Patent No. 48153, rice grains dried under reduced pressure are
Put in boiling water and boil, then wash the swollen rice with water.
Cut and soak in saline, drain again, and freeze.
This is a method of air drying.

The prior art 2 is disclosed in, for example, Japanese Patent Laid-Open No. 60-
As described in Japanese Patent No. 16564, 3-5 for rice.
Cook rice with double the amount of water and remove stickiness with cold water.
And soak in sorbitol solution, then drain
Then, it is frozen rapidly and then freeze-dried in vacuum.
It

On the other hand, the instant porridge is not produced by
Although it is a method of manufacturing rice, as prior art 3, for example, Japanese Patent Laid-Open No.
Cook rice as described in JP-A-61-209558
After dipping the obtained cooked rice in water to swell it and draining it,
There is a method of aging treatment, followed by slow freezing treatment and drying.
It That is, at the time of passing through the maximum ice crystal growth zone during preliminary freezing
I proposed the concept of the freezing condition called "ma", which
The processing steps are simplified.

[0007]

In the above-mentioned prior art 1,
Put the dried rice under reduced pressure in boiling water to heat it
The pretreatment method is complicated, such as immersing in
That the freezing rate and other conditions are not fixed
Therefore, there are many problems in terms of reproducibility and industrialization.
It was Further, also in the above-mentioned conventional technique 2, after cooking rice, it is not viscous with cold water.
And remove it by immersing it in sorbitol solution and draining it.
Requires a complicated pretreatment process, and the freezing speed
Stable and good resilience due to rapidity
Therefore, as in the case of Conventional Technique 1, reproducibility and industrialization
There was a problem in terms. Further, in the above-mentioned conventional technology 3,
It is intended for cooked rice with a relatively low water content.
For porridge with water content far exceeding 80%, dry
There is a problem that it is not applicable because there is a lot of broken rice in Japan.

All of the above prior arts 1 to 3 are frozen.
It is drained before tying and freeze-dried single grain rice grains.
Therefore, the drying process and subsequent manufacturing processes, or storage
Rice grains are easily crushed during pipe and transportation, and even if restored, they will remain as rice grains.
There was a problem that the texture of the product was impaired. The present invention is a porridge and porridge
The purpose of this study is to establish a method for producing freeze-dried porcelain containing ingredients, which can be instantly and easily restored by pouring hot water, and which does not impair the texture of rice grains and the pasteiness of porridge. And

[0009]

The present invention solves the above problems.
Therefore, in the manufacturing method of freeze-dried porridge,
It is characterized by being configured. That is, Invention 1 was washed
After soaking rice in water, drain it and heat it with 6 to 10 times water
And made it into alpha-like porridge.
Is packed in a container made of resin or metal, and -5 ° C to -1 ° C.
The maximum ice crystal growth zone of the plank at a freezing rate of 2 mm / h
Pre-freeze into blocks with slow freezing as follows,
This pre-frozen product is freeze-dried in block form.
It is characterized by the following.

A second aspect of the invention is the same as the first aspect of the invention.
By crushing the dried material freeze-dried into a rock
This is to obtain a coarse-grained dried porridge.

Here, for freeze-dried porridge, only rice is processed.
In addition to rice, various ingredients are added to rice and processed to cook
It goes without saying that the case of including is included. Also plan
The freezing speed of KU is when the thickness of the frozen object is Hmm.
In addition, it takes Z hours for the product temperature in the center to drop to the specified temperature.
Then, the velocity v expressed by the following equation 1 is referred to.

[0012]

[Equation 1] v = (H / 2) / Z (1)

Further, the drying of coarse particles in the above-mentioned invention 2
A porridge is a state in which multiple single-grain rice grains are aggregated and integrated.
Of dried porridge.

[0014]

[Function] The plank is frozen after it has been converted into alpha-like porridge.
Slowly freeze at a speed of 2mm / h or less
Therefore, the lyophilized porridge obtained is solid in the pouring hot water.
Quickly penetrates inside the rice porridge for stable and good restoration.
Show. Also, make a porridge-shaped container made of resin or metal
And then pre-frozen into blocks, and then pre-frozen
The rice grains are freeze-dried in block form,
There is a drying process or a manufacturing process after that, which is not made into single particles
It is difficult to crush individual rice grains during storage and transportation, and one meal
Blocks can be made for each unit.

[0015]

[Examples] First, the inventors of the present invention found that the rate of addition of water (amount of water added / amount of polished rice) when cooking rice porridge and the time required for passage through the maximum ice crystal growth zone during preliminary freezing affect the restoration. It was estimated, and the restoration ratio was determined by changing the water addition rate and the passage time.

The water addition rate to rice was 6 times (whole porridge), 7 times (7 minutes porridge), 10 times (5 minutes porridge), and the heat-gelatinized porridge was put in a container made of styrene resin to a thickness of about 15 mm. It was filled so that These are the maximum ice crystal growth zones (-5
Frozen in an atmosphere lower than (.degree. C. to -1.degree. C.). The passage time in the temperature range was set to 4, 8, 12, and 16 hours, and the freeze-dried product by a conventional method was reconstituted with an appropriate amount of hot water according to the amount of water added. The results are shown in Table 1.
You.

[0017]

[Table 1]

As is clear from Table 1, the water addition rate and the maximum ice
The transit time of the crystal growth zone affects the recoverability of dried products.
The larger the water content, the larger the maximum ice crystal growth.
The longer the band passes, that is, the slower the freezing speed,
It was found that the recoverability was good.

Example 1 1.0 kg of polished rice was washed and pre-soaked in water at 20 ° C. for 2 hours. After draining, 6.0 kg of water was newly added and heated, and the state of slight boiling was maintained for 40 minutes. The resulting porridge was lightly stirred and filled in a container made of styrene resin so that one serving of 120 g had a thickness of about 25 mm. This was pre-frozen under the conditions that the maximum ice crystal growth zone transit time was 6.5 hours, and freeze-dried by a conventional method. When the obtained solid dried porridge was reconstituted with 150 cc of hot water, stirring was required, but it was completely reconstituted in about 2 minutes, and the thickness and flavor peculiar to the porridge could be reproduced.

Example 2 0.9 kg of polished rice and 0.1 kg of glutinous rice were washed and pre-soaked for 2 hours in 6.0 kg of water in which 0.05 kg of salt was dissolved. This was heated and kept in the state of slight boiling for 40 minutes.
The resulting porridge was lightly stirred and filled in a container made of styrene resin so that one serving of 120 g had a thickness of about 25 mm. This was pre-frozen under the condition that the passage time of the maximum ice crystal growth zone was 12 hours, and freeze-dried by a conventional method. When the obtained solid dry porridge was reconstituted with 150 cc of boiling water, the thickness and flavor peculiar to the porridge could be reproduced by instantly reconstitution and stirring.

When freezing a food having a certain thickness,
Generally, ice crystals grow from the outer periphery of foods toward the center, but the speed is not constant. It is said that this difference is due to the non-uniformity of the freezing method, the shape, and the components. Above but the definition of freezing rate there are various ideas, since there is a close correlation between the resilient due to the growth and hot water after lyophilization of ice crystals, the freezing rate of Planck advocated
It was decided to consider the results of Example 1 and Example 2 .

According to Planck's idea of the freezing rate, as expressed by the above equation 1, how much the ice front at -5 ° C, which is the low temperature side of the maximum ice crystal growth zone, penetrates from the surface to the inside in 1 hour. The freezing speed is defined by the distance of the squid.

Looking at this in the first embodiment, v ₁ =
It becomes 1.92 mm / h, and when looking at Example 2, v ₂
A result of 1.04 mm / h was obtained. That is, when the freezing speed was about 2 mm / h, it took some time to restore the freeze-dried product after pouring hot water, but porridge was recovered well, and at about 1 mm / h, it became instantly good. It was confirmed that a porridge to be restored could be obtained.

[0024]

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to produce freeze-dried porridge.
And the pretreatment process can be simplified, and you only need to pour boiling water
It is possible to produce dry porridge that is stable and restores well.
It Also, since it is freeze-dried in block form, unlike retort or canned products, there is no change with time such as rice becoming pasty, and individual rice grains do not have single granules.
Because it is hard to be crushed, the texture of rice grains is maintained and the flavor is good.
A dry porridge can be produced which can be reconstituted into a rough porridge . Moreover, since it can be made into blocks for each meal unit,
Not only is it easy to handle during manufacturing, but it also has the advantage that it can be stored in an extremely compact size during packaging. In addition, by combining with other dried products such as vegetables, or with seasonings, it is possible to easily support a wide variety of products such as Japanese style, Chinese style, and Western style.

Claims (2)

(57) [Claims] 1. The washed rice is soaked in water and then drained,
Heated α phased mushy and without with 10 volumes of water, what has become the α of the so mushy, filled in a resin or a metal container, the maximum ice crystals -5 ℃ ~-1 ℃ the growth zone, to be equal to or less than the 2mm / h at a freezing rate of Planck's slow freezing
A method for producing a freeze-dried porridge, which comprises pre-freezing into a block shape with the above, and freeze-drying the pre-frozen one in a block shape . 2. The dry porridge in coarse particles is obtained by crushing a dried product freeze-dried in a block shape.
A method for producing freeze-dried porridge as described above.