WO2007051220A1

WO2007051220A1 - Gravity operated soy curd press

Info

Publication number: WO2007051220A1
Application number: PCT/AU2005/001690
Authority: WO
Inventors: Eric Hsu
Original assignee: Eric Hsu
Priority date: 2005-11-02
Filing date: 2005-11-02
Publication date: 2007-05-10

Abstract

A gravity operated press (10) for producing a compressed soy product comprising an upright stack of moulds (13), each mould containing soy curd mixture or a packet of cloth wrapped soy curd mixture. The soy curd mixture or packet in the bottommost mould (16) in the stack is compressed by the weight of the moulds containing mixture or packets above it, wherein, removal of the bottommost mould and emptying it of the compressed soy or packet allows the mould to be returned to the top of the stack to be reloaded with fresh soy mixture or new packet, and wherein, each moulding turn, moves to the bottom of said stack, to be emptied and returned to the top of the stack.

Description

GRAVITY OPERATED SOY CURD PRESS

Field of the Invention

This invention relates to the manufacturing of a soy curd product, in particular but not exclusively to the manufacturing of a compressed linen wrapped soy curd product that is popular in Asian cuisine.

Background of the Invention

The consumption of soy bean curd has become very popular worldwide as a result of greater awareness of its health giving and beneficial properties. In most Asian countries such as Taiwan, the Peoples Republic of China and Japan, methods of soy bean production have not changed very much from its labor intensive origins dating back many centuries. One form of soy bean curd, that is considered a delicacy in Asia, is that which is made by wrapping fresh soy curd in cheesecloth and compressing the soy curd to release excess liquid thereby forming a slab of a firm consistency which can be cooked without loosing its shape or texture.

Prior methods and equipment for manufacturing such products include the use of multiple compressed air presses to compress the soy bean curd in an assembly line fashion. The method is labor intensive and involves a number of workers to fold packets of cloth wrapped soy curd and pressing them with a row of pneumatic presses which we are able to press up to between four to six packets at a time. Benches of individual presses require a large amount of room as there can be up to a dozen pressing stations located along the bench. Such manufacturing facilities are often located in a confined space and are operated by a husband and wife team with the help of other family members. The work is of a manual nature and often in non-air conditioned premises causing the workers to sweat profusely. With reduced hygiene standards in most of such home based factories, the soy products are often unsuitable for export where they would rarely meet the health standards of more developed countries.

While tofu or soy consumption is now extremely popular in Western countries, the present market for these types of product appears to be unlimited. The current method of producing of cloth wrapped compressed soy curd is also unsuitable for export production because of the use of mainly timber moulds and equipment which is difficult to clean properly. Materials such as stainless steel and plastics which can be cleaned easily are yet to find their way in such production lines and establishments.

Moulds are also frequently left to dry in the air after being hosed down and drying is often in the sun. The wooden surfaces are often not thoroughly cleaned and bacterial contamination of residual soy in the wood fibers is an inevitable health hazard. The use of compressed air from cylinders or electrically operated compressors are also an added cost which reduces profit margins that can be applied to improve the standard or change the current method of production.

As the work is labor intensive, injuries to workers, down time and difficulty in recruiting skilled workers are also problems for proprietors of such businesses. The transport of soy curd mixture for wrapping is usually by manually ladling it onto the wrapping cloths. In a more automated application, it can however, be supplied by a continuous curding apparatus as described in international patent application WO2004/071206.

It is therefore an object that the present invention seeks to ameliorate some of the disadvantages associated with prior art methods and equipment used in manufacturing compressed soy curd or to at least provide the public with an alternative and useful choice.

Summary of Invention

According to a broad aspect, the invention resides in a gravity operated press for producing a compressed soy product including in combination:

An upright stack of moulds, each moulds containing soy curd mixture or a packet of cloth wrapped soy curd mixture,

the soy curd mixture or packet in the bottommost mould in the stack compressed by the weight of the pressing moulds and mixture or packets above it, wherein, removal of the bottommost mould and emptying it of the compressed soy or packet allows the mould to be returned to the top of the stack to be reloaded with fresh soy mixture or packet, and wherein, each mould in turn, moves to the bottom of said stack, to be emptied and returned to the top of the stack.

In a more specific aspect, the invention resides in a gravity operated press for producing a compressed soy curd product including

an upright housing adapted to house a vertically stacked plurality of pressing moulds, each mould containing soy curd mixture or a cloth wrapped packet of soy curd mixture,

the bottommost mould and soy mixture or packet compressed by the weight of the rest of the overlying moulds and mixture or packets,

the housing associated with lifting means adapted to lift the weight of the rest of the stack from the bottommost mould and mixture or packet

ejection means adapted to eject the bottommost mould on lifting the rest of the stack by the lifting means wherein, the compressed mixture or packet is then emptied from the said mould,

conveyer means adapted to convey the emptied mould to the top of the stack wherein, it is re-loaded with fresh mixture or packet, and

wherein in operation,

each mould and mixture or packet in turn moves to the bottom of the stack so that it is compressed by the weight of the moulds and mixture or packets stacked above it.

In a preferred version, the moulds have tapered sides so that each mould can be partially inserted into the mould below it to compress the packet.

Where the moulds have tapered sides, the soy curd mixture does not have to be wrapped with cloth into packets prior to compressing

Preferably the moulds are perforated to allow excess liquid to be drained in compressing the soy mixture.

Preferably, the soy curd is formed by a continuous curding process prior to being compressed.

Preferably, the wrapping cloth used to wrap the curd is cheesecloth or an equivalent open-weave material or fabric. Suitably, the wrapping cloth is positioned over the mould by a frame encompassing the mould so that as the soy curd is placed substantially in the center of the cloth, it can be wrapped into a packet within the confines of the frame.

Suitably, each mould is configured to enable the lifting means to engage and lift the mould and the moulds above it.

Preferably the lifting and conveyer means are hydraulic or pneumatic telescopic rams having concentric extendable portions collapsible into one other.

Preferably, the moulds are square or rectangular in shape. The moulds can each have a plurality of compartments or cells to hold the soy mixture or individual packets of soy mixture.

Preferably, the moulds are made from a material such as plastic or stainless steel which is easily cleaned.

Preferably, the manufacturing of compressed soy curd product by the apparatus herein described is minimally a two-man operation.

In another aspect, the invention resides in a method of manufacturing a compressed soy curd product including the steps of

(a) loading soy curd mixture or cloth wrapped packets of soy curd mixture into moulds,

(b) stacking each loaded mould on top of one another whereby the bottommost mould and soy mixture or packet is compressed by the weight of the rest of the stack above it, (c) lifting the rest of the stack thereby freeing the bottommost mould and mixture or packet,

(d) ejecting the bottommost mould and mixture or packet from the stack,

(e) emptying the compressed soy mixture or packet from the mould,

(f) conveying the empty mould to the top of the stack and reloading it with fresh soy mixture or packet, and

(g) repeating the steps c-f.

Preferably the ejection means is a hydraulic or pneumatic ram adjusted to push the mould containing the mixture or packet in a horizontal or sideways direction.

Brief description of the drawings

In order that the invention be better understood and put into practical effect reference will now be made to accompany drawings wherein:

Figure 1 shows a front elevation of a preferred embodiment according to the invention,

Figure 2 shows a side elevation of the embodiment of figure one, and

Figure 3 and Figure 4 show detail of the moulds according to the invention. Detail description of the drawings

Referring now to the drawings and initially to Figure 1 , there is shown a front elevation of a gravity operated press 10 for producing a compress soy curd or tofu product.

The press 10 comprises an upright housing 12 containing a stack of moulds 13 with soy curd mixture or packets of wrapped soy curd mixture. The moulds contained in the upright housing 12 adapted to hold a vertical stack of moulds 13 so that the bottommost mould 16 is compressed by the weight of the moulds and mixtures or packets above it.

The housing is associated with lifting means in the form of telescopic hydraulic ram 14 which is adapted to lift the whole stack bar the bottommost mould 16 so that the bottommost mould can be ejected sideways by means of a hydraulic ram ejector means 18. The ejected bottommost mould is then emptied by the worker 20 located at the bottom of the housing and return to the stack of empty moulds 22 on the left wherein the empty moulds 22 are lifted by a conveyer means in the form of a second hydraulic telescopic ram 26. The empty moulds 22 are conveyed to the top of the housing 28 wherein they are refilled with soy curd mixture or packets of wrapped soy curd mixture by the second worker 30 located at the top of the housing. On refilling the empty moulds 22a the worker at the top of the housing places them on the top of the other moulds on the stack on right hand side such that the production is a continuous cycle.

In a preferred embodiment, the moulds 40,42 shown in Figure 3 have tapered sides so that each mould can be partially inserted in the mould below so as to compress the packet or soy curd mixture. The tapered sides 40a, 40b, 42a, 42b of the moulds allow soy curd mixture 41 , 43 which has not been wrapped with cloth to be compressed. Preferably the moulds are perforated 40e, 40f to allow excess liquid 45 to be drained when the soy mixture is being compressed. Although not shown by the drawings, the soy mixture can only be ladled into the moulds or can be fed by a continuos curding process prior to being compressed such as that disclosed by WO2004/071206.

The wrapping cloth used to wrap the soy curd is preferably a cheesecloth or linen or an equivalent open weave fabric or material. Not shown is the wrapping process wherein a wrapping cloth is positioned preferably over the mould with a frame encompassing the mould so that the soy curd is placed substantially in the center of the cloth and can be wrapped into a packet within the confines of the frame.

Suitably each mould is configured to be enabled to be lifted by the lifting means and as shown in Figure 3 and Figure 4, the moulds 40, 42 have extensions 40c, 40d, 42c to the sides of each mould wherein the lifting means can be inserted between the moulds.

The moulds are preferably square or rectangular in shape and are preferably made from materials such as plastic or stainless steal which allows for easy cleaning. Figure 4 (a) - (d) shows various views and detail of the preferred mould 40. The mould is square in shape and comprises several cells 4Og, 4Oh, 4Oi for containing soy curd mixture.

As shown, the manufacturing process is preferably conducted by a minimum of two people however more workers can be utilised to make the process more speedy, albeit more labour intensive. Variations

It will of course be realised that while the foregoing has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is herein set forth.

Throughout the description and claims this specification the word "comprise" and variations of that word such as "comprises" and "comprising", are not intended to exclude other additives, components, integers or steps.

Claims

1. A gravity operated press for producing a compressed soy product including in combination:

2. A gravity operated press for producing a compressed soy product including

the housing associated with

lifting means adapted to lift the weight of the rest of the stack from the bottommost mould and mixture or packet ejection means adapted to eject the bottommost mould on lifting the rest of the stack by the lifting means wherein, the compressed mixture or packet is then emptied from the said mould,

wherein in operation,

3. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the moulds have tapered sides so that each mould can be partially inserted into the mould below it to compress the packet.

4. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the moulds have tapered sides so that each mould can be partially inserted into the mould below it to compress the soy curd mixture whereby the soy curd mixture does not have to be wrapped with cloth into packets prior to compressing

5. A gravity operated press for producing a compressed soy product as claimed in claim 3 or claim 4, wherein the moulds are perforated to allow excess liquid to be drained when compressing the soy mixture.

6. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the soy curd is formed by a continuous curding process prior to being compressed.

7. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the wrapping cloth used to wrap the curd is cheesecloth or an equivalent open-weave material or fabric.

8. A gravity operated press for producing a compressed soy product as claimed in claim 7, wherein the wrapping cloth is positioned over the mould by a frame encompassing the mould so that as the soy curd is placed substantially in the center of the cloth, it can be wrapped into a packet within the confines of the frame.

9. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein each mould is configured to enable the lifting means to engage and lift the mould and the moulds above it.

10. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the lifting and conveyer means are hydraulic or pneumatic telescopic rams having concentric extendable portions collapsible into one other.

11. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the moulds are square or rectangular in shape.

12. A gravity operated press for providing a compressed soy product claimed in claim 1 or claim 2, wherein each mould has a plurality of components or cells for containing soy mixture or packets of soy mixture.

13. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the moulds are made from a material such as plastic or stainless steel which is easily cleaned.

14. A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein a minimum of two people required to operate the press.

15. A method of manufacturing a compressed soy curd product including the steps of

(h) loading soy curd mixture or cloth wrapped packets of soy curd mixture into moulds,

(i) stacking each loaded mould on top of one another whereby the bottommost mould and soy mixture or packet is compressed by the weight of the rest of the stack above it,

(j) lifting the rest of the stack thereby freeing the bottommost mould and mixture or packet,

(k) removing the bottommost mould and mixture or packet from the stack,

(I) emptying the compressed soy mixture or packet from the said mould,

(m)conveying the empty mould to the top of the stack and reloading it with fresh soy mixture or packet, and

(n) repeating the steps c-f.

16.A gravity operated press for producing a compressed soy product as claimed in claim 1 or claim 2, wherein the ejection means is a hydraulic or pneumatic ram adopted to push the mould containing the mixture or packet in a sideways or horizontal direction.

17.A gravity operated soy curd press substantially as herein described with reference to the accompanying drawings.