JPS62186770A - Sterilization of white sauce - Google Patents

Abstract

PURPOSE:To attain necessary sterilization effect in a short time and to prevent the browning of white sauce, by passing white sauce through a pipe in a heating zone under stirring while irradiating the sauce with microwave radiation. CONSTITUTION:White sauce 11 is pumped with a pump 2 to a heating zone 5 and passed through a pipe 4 under stirring with a rotating stirring rod driven by a stirring motor 6. At the same time, microwave radiation generated from a microwave radiator 3 is transmitted through the pipe 4 to heat the sauce at 125-140 deg.C. The sauce is retained in a temperature-keeping zone 8 for 1-4min, sterilized to a sterilization value of >=4.0, passed through a cooling zone 9 and a pressure-controlling zone 10 and discharged.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a method for sterilizing white sauce, which browns when sterilized under conditions to obtain the necessary sterilization value (hereinafter referred to as Fo value) using conventional sterilization methods. It is.

[Prior art]

Conventionally, food sterilization has been carried out by retort sterilization of a food package in which the food is sealed in a container, and the sterilized food package is distributed at room temperature.

In order to distribute the product at room temperature, it had to be sterilized under sterilization conditions that would reach the necessary Fo value.

Currently, white sauce is sterilized under conditions where the Fo value is around 7 to 8, considering the safety factor.

To obtain such conditions, it is necessary to sterilize at 120°C for 20 to 30 minutes, which may cause browning of the white sauce or a change in taste. In order to prevent browning, it is necessary to sterilize under sterilization conditions with an Fo value of 4 or less.
The white sauce was not sterilized sufficiently and there were problems with its distribution at room temperature.

[Problem to be solved]

To provide a method for sterilizing white sauce, which does not cause browning or the like even when sterilized at a necessary Fo value and can be distributed at room temperature for a long period of time.

[Means for solving problems]

A microwave sterilizer consists of a supply section, a heating section with a microwave irradiation section on the outside of the pipe made of a heat-resistant material that can transmit microwaves, a temperature holding section, a cooling section, and a discharge section. pass through the white sauce while stirring, irradiate it with microwaves at the same time, set the heating temperature of the white sauce in the range of 125°C to 140°C, and set the passage time through the temperature holding part for 1 minute to 4 minutes to determine the sterilization value. 4
．． It has become possible to sterilize white sauce, which is sterilized at temperatures above 0.

[Effect]

Since the temperature of the entire white sauce reaches the sterilization temperature in a short time, the necessary Fo value can be obtained even if the time to maintain the white sauce at the sterilization temperature is as short as 1 to 4 minutes.

Furthermore, since the time in the high temperature atmosphere is short, the white sauce does not brown.

〔Example〕

FIG. 1 is a schematic explanatory diagram of the sterilization method used in the sterilization method of the present invention. First, white sauce (11) is placed in a hopper (I).
A mono pump (2) for conveyance is provided at the lower end of the hopper (1), and the white sauce is sent to the heating section (5) by this pump (2). This heating part (5)
is a pipe made of heat-resistant material that can transmit microwaves (
A microwave irradiation section (3) is provided outside the pipe (4), and a stirring rod (not shown) rotated by a stirring motor (6) is provided inside the pipe (4).

The white sauce sent to the heating section (5) passes through the pipe (4) while being stirred by the stirring rod, and at the same time,
By microwave irradiation from the microwave irradiation part (3),
The heating temperature is 125°C to 140°C.

After the temperature of the heated white north is measured by a temperature sensor (7) provided in the line, it is discharged through a temperature holding section (8) that maintains the sterilization temperature and a cooling section (9).

A pressure control section (10) is provided in the discharge section, and the heating section (5), temperature holding section (8), and cooling section (9) maintain positive pressure, and the heating section (5) can sterilize. It is said that

Here, the passage time of the white sauce through the temperature holding section (8) is 1 to 44 minutes, and sterilization is performed to reach the necessary sterilization conditions.

Next, an experimental example of the present invention will be explained.

A refrigerated white sauce was supplied to the hopper of the apparatus shown in FIG. 1 and sterilized under the conditions shown in Table 1 below.

Table 1 The passing time is the passing time through the temperature holding part, and the one passing time was changed by changing the length of the temperature holding part.

At the same time, the white sauce was heat sterilized in an atmosphere at 120° C. for 25 minutes using a steam retort sterilizer.

When sterilization was carried out under the conditions in Table 1 above, the temperature immediately after passing through the heating section (a) and the temperature at the inlet of the cooling section (b) were measured, and the average sterilization temperature was calculated from the temperatures measured at the two points, Table 2 shows Fo values based on this temperature.

Table 2 (a), A, B, C! , E, and I showed no browning (predetermined Fo values were obtained).

(B) and F showed some browning, but there was no problem as a product.

(C) In D, no browning was observed, but the predetermined Fo value was not reached.

), G reached the predetermined Fo value, but the heating time was long and browning was observed.

(Hol, I reached the predetermined Fc value, but the heating temperature was high and it burned inside the pipe.

On the other hand, the retort sterilized product had an Fc value of 9.6, but the heating time was long (and there was significant browning).

〔effect〕

The present invention uses internal heating to obtain the necessary sterilization value in a short period of time, so not only is sufficient heat sterilization carried out, but the short heating time also prevents the white sauce from turning brown, and also prevents the white sauce from becoming brown due to overheating. No change was observed, and suitable sterilization was possible.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram showing an example of a sterilizer used in the sterilization method of the present invention. (1)...Hopper (2)...Pump (3
)...Irradiation part (41...Pipe (5)...Heating part (6)...Stirring motor (7)...Temperature sensor (8)...Temperature holding part (9)... Cooling section
00)...Pressure control section fill...White sauce Figure 1

Claims (1)

[Claims] A microwave sterilizer consists of a supply section, a heating section with a microwave irradiation section on the outside of the pipe made of a heat-resistant material that can transmit microwaves, a temperature holding section, a cooling section, and a discharge section. is passed through the white sauce while stirring, simultaneously irradiated with microwaves, the heating temperature of the white sauce is in the range of 125°C to 140°C, and the passing time through the temperature holding part is 1 to 4 minutes, and the sterilization value is 4. A white sauce sterilization method that sterilizes at temperatures above 0.