Description:TECHNICAL FIELD
[0001] The present invention is related to food sterilizing, stabilizing apparatus and method.
BACKGROUND
[0002] Conventionally, solid food is generally heated and sterilized under pressure after the food is filled in sealed containers. However, with such a conventional method of sterilization, the food can be susceptible to bear an odor specific to retort treatment because it is mostly contained in such sealed containers and/or requires a particularly long processing time because the food has to be heated with air contained in sealed containers.
[0003] On the other hand, a variety of sterilizing apparatuses are already known for successively feeding food into a sealed sterilizing chamber for heating and sterilizing the food at high temperature or at high temperature and under high pressure. With any of these sterilizing apparatuses, however, a conveyor means has to be arranged within the food heating and sterilizing chamber of the apparatus in order to advance the food fed to the apparatus further into the chamber. A conveyor means arranged within a sealed chamber can make the entire configuration of the apparatus rather complicated and disadvantageous from the viewpoint of maintaining the chamber in an aseptic state.
[0004] The high moisture content of these ready-to-heat products requires special steps to be taken in order to render them sufficiently stable for storage and distribution through conventional retail channels.
[0005] Therefore, there is a need of process and apparatus for food sterilizing, stabilizing apparatus which overcomes the aforementioned problems.
SUMMARY
[001] Embodiments of the present disclosure present technological improvements as solutions to one or more of the above-mentioned technical problems.
[002] Before the present subject matter relating to method to produce a stabilized food product and apparatus thereof, it is to be understood that this application is not limited to the particular system described, as there can be multiple possible embodiments which are not expressly illustrated in the present disclosure. It is also to be understood that the terminology used in the description is for the purpose of describing the implementations or versions or embodiments only and is not intended to limit the scope of the present subject matter.
[003] This summary is provided to introduce aspects related method to produce a stabilized food product and apparatus thereof. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the present subject matter.
[004] In one embodiment, a method for the production of a stabilized packaged food product comprising the steps of: filling a tray with a predetermined quantity of a food starting material; introducing the tray into a pressure vessel and conveying the tray through the pressure vessel while performing the following steps in sequence inside the pressure vessel: (i) treating the food starting material with high-temperature pressurized steam to sterilize the material, and (ii) dosing the sterile food material inside said tray with a predetermined amount of sterile water; and (iii) applying a lid to the tray to seal the food product inside the tray while maintaining the tray in a sterile environment.
[005] In another embodiment, an apparatus for heating and sterilizing food that can heat and sterilize food without degrading it. In yet another embodiment, a food sterilizing method comprising the steps of supplying food to be sterilized to a predetermined location between first and second chambers; moving relatively the first and second chambers to form a single air-tight chamber that is defined by cooperation of the first and second chambers, so that the food is encapsulated within the air-tight chamber; introducing a pressurized high temperature steam into the air-tight chamber for sterilization of the food; separating the first and second chamber from each other; and removing the sterilized food.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
[006] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawings to reference features and modules.
[007] Figure 1 illustrates a schematic longitudinal cross-sectional view of a first embodiment of apparatus for heating and sterilizing the food according to the invention.
[0006] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative methods embodying the principles of the present disclosure. Similarly, it will be appreciated that any flow charts, flow diagrams, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.
DETAILED DESCRIPTION
[0007] The invention will now be described with reference to the accompanying drawings and embodiments which do not limit the scope and ambit of the invention. The description provided is purely by way of example and illustration.
[0008] One or more embodiments are provided so as to thoroughly and fully convey the scope of the present invention to the person skilled in the art. Numerous details are set forth, relating to specific components, and methods, to provide a complete understanding of embodiments of the present invention. It will be apparent to the person skilled in the art that the details provided in the embodiments should not be construed to limit the scope of the present invention. In some embodiments, well-known processes, well-known apparatus structures, and well-known techniques are not described in detail.
[0009] The terminology used, in the present invention, is only for the purpose of explaining a particular embodiment and such terminology shall not be considered to limit the scope of the present invention. As used in the present invention, the forms "a,” "an," and "the" may be intended to include the plural forms as well, unless the context clearly suggests otherwise. The terms "comprises," "comprising," “including,” and “having,” are open ended transitional phrases and therefore specify the presence of stated features, integers, steps, operations, elements, modules, units and/or components, but do not forbid the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The particular order of steps disclosed in the method and process of the present invention is not to be construed as necessarily requiring their performance as described or illustrated. It is also to be understood that additional or alternative steps may be employed.
[0010] In a first aspect, the present invention provides a method for the production of a stabilized packaged food product comprising the steps of: filling a tray with a predetermined quantity of a food starting material; introducing the tray into a pressure vessel and conveying the tray through the pressure vessel while performing the following steps in sequence inside the pressure vessel: (i) treating the food starting material with high-temperature pressurized steam to sterilize the material, and (ii) dosing the sterile food material inside said tray with a predetermined amount of sterile water; and (iii) applying a lid to the tray to seal the food product inside the tray while maintaining the tray in a sterile environment.
[0011] The feature of steam sterilizing and water dosing the food product sequentially under sterile steam conditions, followed promptly by sealing the trays under sterile conditions in the steam pressure vessel, provides a very rapid route to commercially sterile products with minimum capital assets. It has been found that extended cooking of the food product following the dosing step is not needed in order to achieve a stable, full moisture, ready-to-heat product. Further advantages of the process are discussed below.
[0012] The initial step of the process comprises filling trays with a predetermined quantity of food starting material. The trays may be formed of any suitable material that is sufficiently heat resistant to keep its shape in the subsequent steps of the process. Thermoformed polypropylene (PP), polyethylene terephthalate (PET) or CPET trays may be suitable, preferably with an ethylene vinyl alcohol (EVOH) oxygen barrier layer. For example a PP-EVOH-PP laminate may be suitable, with the PP selected to provide the necessary heat resistance at 135 C. The laminate thickness is suitably from about 0.8mm to about 1.5mm, for example about 1mm to about I.2mm. The tray suitably has a bottom, straight or tapered side walls, and a flange (lip) at the top for sealing. The bottom and/or the side walls may be profiled in various ways for decorative or structural reasons. In certain embodiments, the tray may be substantially in the shape of a bowl to assist consumption of the food product directly from the tray. Metal foil or metal/polymer laminate trays could also be used, but are not so suitable for subsequent microwave reheating of the food product before consumption. The tray may include metallised susceptor regions to provide localized heating in a microwave oven.
[0013] The depth of the tray and quantity of starting material are normally selected so as to produce a substantially filled tray when hydration of the contents is complete. The starting material is filled into the trays in a layer (bed) that is preferably not more than about 3cm deep, for example from about 0.2 to about 2 cm deep. A uniform bed of food product is desirable, and accordingly the bed height is preferably equalized before performing subsequent steps of the process.
[0014] The food starting material in the processes of the present invention may be any dry or wet solid food material.
[0015] Figure 1 illustrates a schematic longitudinal cross-sectional view of a first embodiment of apparatus for heating and sterilizing the food according to the invention.
[0016] This food heating and sterilizing apparatus 300 is an autoclave. It comprises a heating and sterilizing chamber 301 disposed within the apparatus and provided at a lower portion thereof with a shelf 302 having an upper plate, which is a meshy member. The upper plate of the shelf 302 carries thereon a cylindrical container 303 with a diameter of about 134 millimeters and a height of about 50 millimeters. The cylindrical container 303 is provided at the bottom thereof with holes (not shown) having diameters of about 2 millimeter and arranged at intervals of 3 millimeters. The heating and sterilizing chamber 301 is additionally provided at an upper portion thereof with a steam supply pipe 305 having a plurality of steam supply pipe 304. The steam supply pipe 305 is connected to a steam generating means (not shown) such as a boiler and supplies steam into the heating and sterilizing chamber 301. The steam blow out ports 304 are located substantially directly above the cylindrical container 303 placed on the shelf 302 so that steam blown out of the blow out ports 304 may directly and vertically hit the food 306 contained in the cylindrical container 303. The heating and sterilizing chamber 302 is further provided at a central position of the bottom opposite to the upper plate of said shelf with an exhaust port 307 and at peripheral positions of the bottom with steam supply ports 308.
[0017] Said container 303 is made of a thermally resistive material. Specific materials that can be used for the container include plastic materials, ceramic materials and metals, although the container is preferably a plastic container having no holes at the bottom if a closure is directly fitted thereto to produce a sealed product immediately after the sterilizing operation. While the container 303 may not necessarily be cylindrical, preferably it is tray-shaped or cup-shaped and has an opening having an area equal to or greater than that of the bottom so that the food in the container may be evenly exposed to steam. Furthermore, the food is preferably made very flat in the container so that it may be exposed to steam more uniformly.
[0018] While the embodiment of food heating and sterilizing apparatus 300 comprises a single shelf 302 and a single container 303 arranged on the shelf 302, a plurality of containers 303 may alternatively be arranged on the shelf 302 or, still alternatively, two or more shelves may be provided in the apparatus, each carrying thereon one or more containers 303.
[0019] While any appropriate number of blow out ports 304 may be arranged in the apparatus, the number of blow out ports 304 may preferably be made equal to the number of containers 303, if more than one container 303 is provided in the heating and sterilizing chamber 301, so that there is a one-to-one correspondence. A single blow out port 304 may operate efficiently for sterilization if a plurality of containers 303 are made to move within the heating and sterilizing chamber 301.
[0020] While the above embodiment of food heating and sterilizing apparatus 300 is provided with an exhaust port 307 disposed below the shelf 302, a steam blow out port may alternatively be arranged below the shelf 302 so that steam may hit the food in the container 303 from underneath the food.
[0021] Alternatively, a tall cylindrical container having a plurality of holes along the lateral wall thereof may be used and steam blow out ports may be arranged on the lateral wall of the autoclave so that steam may horizontally hit the lateral wall of the container. If such is the case, the efficiency of the sterilizing operation of the apparatus can be improved by arranging an exhaust port at a location opposite the blow out ports on the lateral wall of the autoclave. Still alternatively, a steam blows out port may be arranged below the container such that steam may hit the lateral wall of the autoclave having a horizontally disposed cylindrical form and an exhaust port may be arranged on the bottom of the autoclave at a position directly below the container. Then, steam proceeds directly downward from above and vertically hits the food.
[0022] For the purpose of the invention, in the specification, "steam" includes saturated steam, superheated steam and any other types of steam that can be used for heating and sterilizing food.
[0023] The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the invention.
, Claims:We claim:
1. A method to produce a stabilized food product, comprising the steps of:
a. introducing a food product into a cylindrical container;
b. placing said cylindrical container onto a shelf within a heating and sterilizing chamber;
c. supplying steam to said heating and sterilizing chamber via a steam supply pipe;
d. subjecting said cylindrical container to heat and sterilization within said heating and sterilizing chamber, thereby stabilizing the food product;
e. removing said stabilized food product from said cylindrical container.

2. The method according to claim 1, wherein said heating and sterilizing chamber maintains a predetermined temperature and pressure during the sterilization process.

3. The method according to claim 1, further comprising the step of sealing said cylindrical container after introducing the food product but before subjecting it to heat and sterilization.

4. An apparatus for the production of a stabilized food product, comprising:
a. a heating and sterilizing chamber;
b. a shelf within said heating and sterilizing chamber for supporting a cylindrical container;
c. a cylindrical container configured to receive and hold a food product;
d. a steam supply pipe connected to said heating and sterilizing chamber for supplying steam to said chamber.

5. The apparatus according to claim 4, further comprising a sealing mechanism for hermetically sealing said cylindrical container.

6. The apparatus according to claim 4, wherein said heating and sterilizing chamber includes temperature and pressure control means for maintaining predetermined sterilization conditions.

7. The apparatus according to claim 4, further comprising a conveyor system for transporting cylindrical containers to and from said heating and sterilizing chamber.

8. The apparatus according to claim 4, wherein said cylindrical container is removably placed onto said shelf within said heating and sterilizing chamber.
9. The apparatus according to claim 4, further comprising a control system for regulating the sterilization process based on predetermined parameters.