JPS6029117A - Vacuum fryer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vacuum frying apparatus. Several vacuum frying devices have been announced so far. For example, special public service 54-2
5109, Special Publication No. 53-17666, etc.

Each of these consists of a pressure adjustment chamber at the front, a fryer, a pressure adjustment chamber at the rear, and attached heating equipment, oil circulation equipment, vacuum generation equipment, steam condenser, and condensed water supplementation equipment.

The most important of these, the fryer, is comprised of an automatic conveyor means, such as a conveyor, for each fryer.

As a result of a detailed study of the process of vacuum frying, the present inventor found that vacuum frying consists of at least two or more stages.

That is, the first stage is a process accompanied by extremely violent bumping phenomena, and the second stage is a quiet evaporation phenomenon.

The above is considered to be the rapid evaporation of the gas contained in the raw material and the water loosely bound to the tissue, and the latter stage corresponds to the evaporation of so-called bound water, which is strongly bound to the tissue.

One of the applications of the vacuum frying method is thought to be snacks with crisp textures such as vegetables and fruits.

For this purpose, at least the final moisture content should be kept below 3%.
, must be strained. If it is more than this, the crispiness required as a snack cannot be obtained.

By the way, at the stage where the rapid evaporation of water is completed, the moisture content of the raw material has not yet reached 3%, and crispness cannot be obtained.

In the latter stage, the water-soluble components in the raw materials become waste, and their water activity becomes extremely low, and the vapor pressure of water is low. Therefore, the transpiration is extremely complicated, and even in actual vacuum frying, the transpiration in the latter half is much more than the first half. It takes time to drink 1
．． It requires 5 to 2.5 times as much.

Therefore, in order to complete frying in a short time in a factory-scale implementation, the first and second stages are divided into 1.4
It is preferable to make

If frying is carried out in batches, this can be done by confirming the end of the first period (this can be visually confirmed by the rapid subsidence of the tsutsuto phenomenon) and changing the frying conditions.

In the case of a continuous type, it is necessary to constantly set at least two operating conditions as in the invention.

To shorten the frying time in the later stages, (1) Raise the frying temperature.

(2) Increase the degree of pressure reduction.

There are two possible methods, but (1) is not practical. This is because if the frying temperature is increased to a level higher than necessary, undesirable denaturation such as fading, discoloration, and browning will occur.

In the case of eating fruits and vegetables, it is generally difficult to raise the oil temperature above 120-130'c. In addition, unlike the previous period, the water in the raw materials does not evaporate rapidly, so the V4 effect, which is sensitive to the latent heat of vaporization of water, is not affected by transient increases in oil temperature, and the quality is extremely insensitive. Ru.

Therefore, method (2) has to be adopted, but according to the experience of the present inventors, it is better to maintain the degree of reduced pressure at least 20 Torr, preferably 10 Torr or less.

In fact, during the first stage, large amounts of water and gas evaporate rapidly in a short period of time, so it is difficult to maintain such a high degree of decompression even with fairly large vacuum pumps and vacuum equipment. .

This can be seen, for example, in Japanese Patent Application Publication No. 58-40037,
It is also mentioned in No. 3-28494 and Japanese Unexamined Patent Publication No. 54-20160. According to the experience of the present inventor, it is not necessary to maintain the above-mentioned degree of decompression at a high level, and there is no need to reduce the pressure to at least 6 tll Torr in the latter stage.In the latter stage, water evaporation ( Since R is extremely faint,
Maintaining a high degree of vacuum is not very difficult.

The apparatus of the present invention is comprised of a front air pressure adjustment chamber, a rear air pressure adjustment chamber, an attached oil heater, an oil circulator, a vacuum generator, a condensing oni bottle, etc., like a general reduced pressure or pressure frying apparatus.

As mentioned above, in order to construct at least two or more different fryers, it is necessary to connect two or more isolated fryers, but in the present invention, one This is achieved by dividing the fryer by a bulkhead submerged in oil and placing the rear section higher than the front section.

In the vacuum frying method, it is more important to keep the difference in the reduced pressure conditions constant than the temperature difference in the frying oil.

Generally, the pressure is 60-100 Torr in the first half and 20 Torr in the second half.
Torr + preferably 10 Torr or less).

By the principle of the communicating pipe, the present invention can overcome this pressure difference (~90%
Torr) is achieved by the difference in oil column.
If the specific gravity of oil is 0.95 and the difference between the front and rear curved surfaces is h, the pressure difference to be compensated by the 40 columns is 0.95X
h, its size is 760:10000m
+n-5O-90: 0.95 X h.

It will be about.

Therefore, the upper space of the fryer is divided into front and rear parts by the partition wall immersed during the bend, and the oil level at the rear is made h higher than that at the front.
If the front space and the rear space are raised by that amount, the front space and the rear space can be maintained at their optimum negative values.

In principle, two-stage frying can be carried out if the bottom of the fryer is made flat and the raw materials are transferred horizontally to the front and rear, for example by a net conveyor.

Only 1. However, as a general rule of thumb when it comes to frying, the exchange rate of the song is still low, the deterioration of the fly song is small, the song f1 carried away by the fly body is constant as long as the operation is under certain conditions, and the amount of 411 in the fly is as small as possible. is better.

Therefore, lift the bottom of the fryer at the rear and lift it at least 4 times.
．． ) It is wise to prevent the increase in bending loss caused by the difference in curved surfaces by providing a step of about 1+. Of course, the above-mentioned values of 11 are merely examples, and may vary depending on the later condition settings.

As an internal transport means, for example,
There is also a method of storing the raw material 1 in a basket and moving it directly to the conveyor 2, as shown in No. 9. A method of transport may also be adopted.

In vacuum frying, the water vapor generated abnormally increases its volume according to Boyle's law, causing the raw materials to float violently in the oil, and in some cases even rise to the surface at once, making it difficult to fry them uniformly.

In order to avoid this, it is necessary to restrict the movement of the raw material to some extent and forcibly move the raw material forward, and this is attempted to be achieved by using two conveyors facing each other. In this case, it is better to provide a protrusion L-1 in the form of a baffle plate at right angles to the direction of movement of the conveyor. The protrusions may be attached to one side of the conveyor in closer contact with the other, or slightly closer to each other (maintaining a distance of several centimeters), or protrusions may be provided on both sides to hold the conveyor in close contact with the other conveyor. (It does not matter whether the upper and lower protrusions are provided at the same position or alternately.) In this way, the portions separated by each baffle plate form a basket, which is convenient.

A good material for the conveyor would be a punched metal plate or net 1, which has enough gaps to prevent the raw materials from escaping.

Further, instead of the conveyor, a shaft may be provided in the advancing direction, and a helical plate-shaped protrusion may be attached to the shaft and the material may be rotated to advance the raw material continuously. In this case, either make the bath part of the fryer a part of the circle that is almost in close contact with the helix, or surround the area around the helix inside the bath with a punched metal plate or net with enough holes to prevent the raw materials from escaping. is good. In addition, in order to counteract floating, a rod-like or plate-like projection can be provided on the spiral projection (or on the shaft portion), and the raw material can be appropriately stirred by the movement of these obstacles due to rotational movement.

As mentioned above, when using a conveyor, the feeding part, the front part of the fryer, the rear part of the fryer, and the lifting part can be formed by bending the entire conveyor along the bottom of the fryer for charging, immersion in oil, and lifting. When using i'+t1 part, shirt l- at the back
It is conceivable that the feeding section, the connecting section between the front section and the imm section, and the lifting section can be constructed using a single layer, a 21 layer and 1 conveyor, or a basket conveyor.

Generally, the frying time in the first fryer is 5 to 10 minutes.
In the second fryer, it takes about 10 to 15 minutes.

As for the air pressure adjustment chamber attached to the fryer, the conventional city version will be sufficient.

As for the heating means, you can install an oil heater outside a part of the fryer and circulate the oil, or you can install a heater inside the fryer (
Either by installing a heating device using a heating medium such as steam, electric heat, or dow→gnome, or by heating the vessel wall with steam, direct flame, hot air, etc., or by using a combination of these.

Conventional vacuum generators, distillate condensers, and 1-laps may also be used.

However, these require installation in two ways: at the front and at the rear of the fryer.

In order to maintain the height of the front and rear curved surfaces at a constant level, a curved surface detector (float type, electric resistance type, etc.) is installed on each side, and the oil fleas are adjusted using a discharge pump or a supply pump. It's good.

The present invention will be specifically explained below with reference to the drawings, but the scope of the present invention is not limited to these figures alone.

[Brief explanation of the drawing]

FIG. 1 is an external view of the vacuum frying apparatus of the present invention.
There is a front air pressure adjustment chamber 2, a front air pressure adjustment chamber 3 at the front of the fryer, and a rear air pressure adjustment chamber at the rear air fryer 4. In the figure, 1 is the new 41 tank, 2 is the oil heater 3, the front part of the fryer 4 is the rear part of the fryer 5 is the strainer, 6 is the oil circulation pump 7 is the oil level sensor 8 is the cable connecting the oil level sensor and the pump. show. Note that the solid line in the figure indicates a pipe through which oil passes. FIG. 3 shows an ini 1 diagram of the coercive frying device of the present invention using a counter-moving conveyor as a transfer means. In the figure, 1 indicates the door 2, the front portion of the fryer 3, the rear portion of the fryer 4, the conveyor 5, the oil level sensor 6, and the Ia wall 7 indicating the oil level. FIG. 4 shows a sectional view of the vacuum frying apparatus of the present invention, which uses a shaft having a helical projection as a transfer means. In the figure, 1 indicates a door 2, a front part of the fryer 3, a rear part of the fryer 4, a belt conveyor 5, a shaft 6, a spiral projection 7, a basket conveyor, and 8, an oil level sensor 9, a partition wall. Procedural amendment (formality) 1. Indication of case 1982 Patent Application No. 139150 1
18 Towabehera 2, Title of the invention: Decompression frying device 3, relationship with the case of a person who is a captive IE Patent applicant), <Ji-no (Hi-151S16) Address: 2067 Hongo-cho, Fukuyama-shi, Hiroshima, f. Name 5, Date of amendment order: November 8, 1982 (shipped on 29th of the same month of the same year) 6, Subject of supplementary IF Specification

Claims (1)

[Scope of Claims] (1) The fryer is divided into two parts by a partition wall immersed in oil, and the curved surface of the rear part is made higher than the front part by the height of the oil column corresponding to the pressure difference between the degree of decompression between the front part and the rear part. A vacuum frying device characterized by holding. (2. Claim (1), the vacuum frying device is characterized in that the transfer means in the fryer are two conveyors that advance oppositely at the same speed. (3) Claim (1) 1) A vacuum frying device i:i characterized in that the transfer means in the fryer is based on the rotation of a shaft attached with a spiral plate-like protrusion.