JP2006314271A - Method for sterilizing and heat treating granular food and food material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for heating and sterilizing, or cooking and sterilizing by the addition of heat treatment, granular food and food material in a condition of being held in a container, and sealing the container, and also treating containers which hold not only a small amount of about over 10 g materials but also over 10 kg materials. <P>SOLUTION: This method comprises heating and sterilizing or cooking and sterilizing by the addition of heat treatment the granular food and food material in a condition of being held (together with air) in a container, and sealing the container, and also can treat containers for holding not only a small amount of about over 10 g materials but also over 10 kg materials. As a result of this, it is possible to solve bad conditions as follows: (1) A conventional method comprising sealing food and food material in a container, heating and sterilizing together with the container followed by addition of heat treatment has a problem that there causes a risk that air in the container swells by heat and breaks the container, so it is necessary to make the container airless; (2) Food and food material must be liquid or soaked in water or oil, and on the point of heat conduction, must be sealed in a small container little by little; (3) a heating temperature is limited to about 100°C or below at which steam is produced and a container is not broken. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for sterilizing granular foods and food materials and applying heat treatment.

Foods and food materials are often cooked by heating or pre-cooked.

Further, many foods and food materials are sterilized by heating, and when stored, they are sealed in containers and kept in a sterilized state.

2. Description of the Related Art Conventionally, food and food materials are sealed in a container, and then the whole container is heated and sterilized, followed by heat treatment.
However, the problem with this method is that if there is air in the container, it may expand due to heat and damage the container, so the container must be free of air.
For this reason, food and food materials must be in liquid form or immersed in water or oil. From the point of heat conduction, heat is transferred to the central part of the container. It must be sealed in a small container.
Furthermore, the heating temperature is limited to the extent that water vapor is generated and the container is not damaged at about 100 ° C. or less.

  The present invention heats and sterilizes powdered foods and food materials in a container, or cooks and sterilizes them by applying heat treatment and seals them, and only a small amount of materials such as about a few tens of grams. In addition, the object is to make it possible to process a container containing several tens of kilograms of material.

  The present invention fills a heat-resistant container having a hot air inlet and outlet with powdered food or food material, feeds hot air into the container and discharges excess hot air from the outlet. The main feature is that the food or food material is heated while keeping the pressure at a predetermined pressure and sterilized, and then the inlet and outlet are closed to seal the container.

  The method for sterilizing and heat-treating the granular food and food material according to the present invention comprises filling a heat-resistant container having a high-humidity hot air inlet / outlet and a powdery food or food material into the high-humidity hot air. In addition to exhausting excess hot air from the discharge port, the food or food material is heated and sterilized while keeping the inside of the container at a predetermined pressure, and the container functions as a part of the overheating and sterilization device. When the process is completed, the material to be treated is sealed in the container, so the filling and packaging process of the container is omitted, and there is no possibility of contact with the outside air before processing and packaging, so that the material is contaminated. There is an advantage that there is no possibility of being.

Here, the sterilization and heat treatment methods for the granular food and the food material of the present invention will be described.
First, a heat-resistant container having a high-humidity hot air inlet and outlet is filled with powdered food or food material, and the container is closed.
The container is molded from a material that has desired heat resistance of about 100 to 300 ° C and non-air permeability, and the shape of bottles, cans, etc., and the amount and internal pressure of the contents are almost unchanged. The bag container swells or narrows due to the above, and the shape and dimensions thereof are not particularly limited.
Depending on the shape and properties of the granular food and food material, filters are attached to the inlet and outlet to prevent the contents from spilling out.
Here, the high-humidity hot air is one obtained by heating water to a temperature of 100 ° C. or higher (water gas), or a mixture of water gas and heated air or nitrogen gas.
Next, an air supply nozzle of a high humidity hot air generator (not shown) is connected to the inlet, and high humidity hot air of about 130 to 300 ° C. is sent to the container, thereby discharging excess hot air in the container. The high-humidity hot air is continuously fed into the container while maintaining the amount and pressure of the gas in the container within a predetermined range.
In this operation, the food or food material to be processed is slightly soft or the surface is moist, and adjacent particles in the container come into contact with each other so that hot air does not easily pass between the particles. If there is something, the inlet is formed at the bottom of the container and the outlet is formed at the top to create an upward flow of hot air in the container, which makes the workpiece to float and make the particles to float. It is recommended that the surface be affected by high-humidity hot air.
In addition, when the container is a bag container, the amount of hot air discharged from the discharge port is appropriately regulated so that the container is inflated, the apparent internal volume is increased, and the tendency to lift the object to be processed is facilitated. It is good to do.
When sterilization and heat treatment of the material to be treated with high-humidity hot air are completed, the high-humidity hot air is stopped from feeding, and the inlet and outlet are sealed to seal the container.
At this time, since the granular food or food material that is the object to be processed is at a high temperature in the container, it takes several minutes to several tens of minutes until it falls to near normal temperature. There is a possibility that the food or food material may be altered in an unfavorable direction.
Moreover, when the hot air filled in the container falls, its volume decreases, the container is depressurized, and the container may be damaged.
When it is necessary to eliminate such possibilities and fears, immediately stop the high-humidity hot air feed and immediately send sterilized air or nitrogen gas from the feed port or a separately formed blower port to the container. The temperature is lowered to the above temperature, the amount and pressure of gas in the container are adjusted, and then the container is sealed.

The fresh tea leaves plucked at the tea garden were sprayed with high-humidity hot air at a temperature of 180-220 ° C and humidity: 40-80% for 35 seconds, then pulverized to 50 mesh, and the high-humidity hot air with a capacity of 1000 ml was sent. The bag mouth was closed by filling 200g into a heat-resistant bag container in which the inlet and outlet were formed.
Next, high temperature hot air with a temperature of 240 ° C and humidity of 60% is sent to this bag container for 15 minutes to heat the powdered tea, and then nitrogen gas is sent to it for 30 seconds to cool it. The apparent size of the bag container Nitrogen gas was discharged until about 500 ml was reached, and the inlet and outlet were sealed to seal the bag container.
Powdered tea became powdery green tea with a strong aroma and strong umami.

Since sterilization and heat treatment are performed in the container and the container becomes a part of the sterilization and heat treatment apparatus, it can be applied to operations such as mixing and melting of materials.

Claims (1)

A heat-resistant container with hot air inlet and outlet is filled with powdered food or food material, high humidity hot air is fed into this container, and excess hot air is discharged from the outlet to determine the inside of the container. A method for sterilizing and heat-treating granular foods and food materials, wherein the food or food material is heated while being maintained at the pressure, and the sterilization is carried out, and then the inlet and outlet are closed to seal the container.