GB2195262A

GB2195262A - Wine filtration

Info

Publication number: GB2195262A
Application number: GB08623504A
Authority: GB
Inventors: Robert Edward William Harris
Original assignee: Individual
Current assignee: Individual
Priority date: 1986-09-30
Filing date: 1986-09-30
Publication date: 1988-04-07
Also published as: GB8623504D0

Abstract

A method of filtering wine, for use by home wine makers dealing with small volumes for example multiples of 5 litres, comprises the use of a thin cellulose/glass fibre pad or sheet which gives a fast flow during filtration, but which would, if used alone, quickly clog and become unusable. Perlite, diatomaceous earth, cellulose or glass fibres is added to the wine at about 1 teaspoon per demijohn (1:1000) and forms a filter bed which increases in thickness as the filtration continues, effectively providing a new filtration surface throughout the whole of the filtration operation.

Description

SPECIFICATION Wine filtration This invention relates to the filtration of wine especially in small volumes by home wine makers. The term filtration means passing the wine through a pad which separates for example suspended particles out of the wine and so improves its clarity and brilliance. The particles may be for example protein, pectin or starch haze, or disturbed sediments of dead yeast cells.

An old filtration technique used asbestos pulp in laid down or preformed pads, but this is no longer acceptable for health reasons.

The present state of the art employs preformed relatively thick pads of cellulose fibres with perlite powder inclusions, or relatively thin sheets of cellulose fibres with borosilic micro-glass fibre content.

The cellulose/perlite pads are relatively slow at the commencement of a filtration operation, but have a relatively long life, that is to say one pad may be used, depending on size, to filter several demijohns of wine, each comprising 5 litres, the number depending upon the amount of filtration required. Excessive muddy wine will naturally clog a filter quicker.

The cellulose/glass fibre pads are initially much faster, and their action is of a different nature, because the sediment may be electrically attracted to the glass fibre. But such pads become clogged more quickly.

Attempts to provide the same life with the celiulose/glass pads which can be obtained with the cellulose/perlite pads involve making the former of the same thickness as the latter, so as to provide a greater volume of material which has to be clogged before the filter becomes ineffective or too slow to be useful, but these are found to be particularly expensive and hence unattractive commercially, and this is due to the cost of the glass fibre content.

The object of the present invention is to provide improvements.

According to the invention, a method of filtering wine comprises dispersing a particulate filtering medium in the wine, and passing the mixture through a preformed filter pad so that initial flow is through the pad alone, and when a layer of the medium has built up on the pad, the flow is also through that layer.

Hence, the longer the filter is in use, the thicker the pad becomes, but effectively a fresh layer of filtering material is being deposited continually, so that the pad does not soon become unusable due.

The addition of the particulate filtering medium to the wine is distinct from the use of finings such as isinglass or Bentonite which operate by precipitation of the dispersed fining material in the container trapping and carrying haze or sediment to the settled out layer. In the present invention, the particulate material may have no interaction with the sediment or haze which is to be filtered whatsoever, until this particulate material becomes part of the filter bed, and then the action can be the ordinary filtration technique of trapping the unwanted particles as they flow through the bed.

It has been found experimentally that the relatively expensive cellulose/glass fibre pad can be used in a particularly thin form, with great economy, and combined with the use of a relatively inexpensive material added to each volume of wine to be filtered, to give long pad life and satisfactory clarity, brilliance and also filtration time cycle.

A presently preferred particulate material to be added to the wine is perlite, of the same order of particle size as commonly used in preformed fibre/perlite filter pads for the purpose. However it is within the scope of the invention to use diatomaceous earth or fibrous material such as the cellulose fibres or even the glass fibres. The latter (glass fibres) might have a particularly efficient filtration effect for the reason explained hereinbefore, but may not be economically acceptable for some purposes.

A typical concentration of particulate material is of the order of one part per thousand, that is to say 1 teaspoon (5ml) per 1 gallon (5 litres).

The invention is believed to be particularly useful where the material to be separated is gelatinous in nature for example a pectin haze which in a severe condition, can rapidly plate and "blind" a conventional filter, but because the surface is continuously renewed in the present invention, this does not occur.

According to a further aspect of the invention, a filtration kit comprises a filter body adapted to support a pad, at least one preformed filter pad for use in said body, and a supply of particulate filtering medium for addition to the wine.

1. A method of filtering wine comprising dispersing a particulate filtering medium in the wine, and passing the mixture through a preformed filter pad so that initial flow is through the pad alone, and when a layer of the medium has built up on the pad, the flow is also through that layer.

2. A method as claimed in Claim 1 wherein the preformed pad is a thin cellulose/glass fibre pad.

3. A method as claimed in Claim 1 or Claim 2 wherein the particulate medium dispersed in the wine is perlite.

4. A method as claimed in Claim 1 or Claim 2 wherein the particulate medium dispersed in the wine is diatomaceous earth.

5. A method as claimed in Claim 1 or Claim 2 wherein the particulate medium dis

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Wine filtration This invention relates to the filtration of wine especially in small volumes by home wine makers. The term filtration means passing the wine through a pad which separates for example suspended particles out of the wine and so improves its clarity and brilliance. The particles may be for example protein, pectin or starch haze, or disturbed sediments of dead yeast cells. An old filtration technique used asbestos pulp in laid down or preformed pads, but this is no longer acceptable for health reasons. The present state of the art employs preformed relatively thick pads of cellulose fibres with perlite powder inclusions, or relatively thin sheets of cellulose fibres with borosilic micro-glass fibre content. The cellulose/perlite pads are relatively slow at the commencement of a filtration operation, but have a relatively long life, that is to say one pad may be used, depending on size, to filter several demijohns of wine, each comprising 5 litres, the number depending upon the amount of filtration required. Excessive muddy wine will naturally clog a filter quicker. The cellulose/glass fibre pads are initially much faster, and their action is of a different nature, because the sediment may be electrically attracted to the glass fibre. But such pads become clogged more quickly. Attempts to provide the same life with the celiulose/glass pads which can be obtained with the cellulose/perlite pads involve making the former of the same thickness as the latter, so as to provide a greater volume of material which has to be clogged before the filter becomes ineffective or too slow to be useful, but these are found to be particularly expensive and hence unattractive commercially, and this is due to the cost of the glass fibre content. The object of the present invention is to provide improvements. According to the invention, a method of filtering wine comprises dispersing a particulate filtering medium in the wine, and passing the mixture through a preformed filter pad so that initial flow is through the pad alone, and when a layer of the medium has built up on the pad, the flow is also through that layer. Hence, the longer the filter is in use, the thicker the pad becomes, but effectively a fresh layer of filtering material is being deposited continually, so that the pad does not soon become unusable due. The addition of the particulate filtering medium to the wine is distinct from the use of finings such as isinglass or Bentonite which operate by precipitation of the dispersed fining material in the container trapping and carrying haze or sediment to the settled out layer. In the present invention, the particulate material may have no interaction with the sediment or haze which is to be filtered whatsoever, until this particulate material becomes part of the filter bed, and then the action can be the ordinary filtration technique of trapping the unwanted particles as they flow through the bed. It has been found experimentally that the relatively expensive cellulose/glass fibre pad can be used in a particularly thin form, with great economy, and combined with the use of a relatively inexpensive material added to each volume of wine to be filtered, to give long pad life and satisfactory clarity, brilliance and also filtration time cycle. A presently preferred particulate material to be added to the wine is perlite, of the same order of particle size as commonly used in preformed fibre/perlite filter pads for the purpose. However it is within the scope of the invention to use diatomaceous earth or fibrous material such as the cellulose fibres or even the glass fibres. The latter (glass fibres) might have a particularly efficient filtration effect for the reason explained hereinbefore, but may not be economically acceptable for some purposes. A typical concentration of particulate material is of the order of one part per thousand, that is to say 1 teaspoon (5ml) per 1 gallon (5 litres). The invention is believed to be particularly useful where the material to be separated is gelatinous in nature for example a pectin haze which in a severe condition, can rapidly plate and "blind" a conventional filter, but because the surface is continuously renewed in the present invention, this does not occur. According to a further aspect of the invention, a filtration kit comprises a filter body adapted to support a pad, at least one preformed filter pad for use in said body, and a supply of particulate filtering medium for addition to the wine. CLAIMS

5. A method as claimed in Claim 1 or Claim 2 wherein the particulate medium dis persed in the wine is cellulose fibres.

6. A method as claimed in Claim 1 or Claim 2 wherein the particulate medium dispersed in the wine is glass fibres.

7. A method as claimed in any preceding claim wherein the particulate medium is added to the wine in the proportion of about 1 part to 1000.

8. A filtration kit for carrying out the method claimed in Claim 1 comprising a body adapted to support a pad, and least one preformed filter pad adapted for use in said body, and a supply of particulate filtering material for addition to the wine.

9. A method of filtration of wine in small volumes by home wine makers as claimed in any of Claims 1 to 7 and substantially as hereinbefore described.