GB2224425A

GB2224425A - A method of treatment of fruit and vegetables

Info

Publication number: GB2224425A
Application number: GB8825927A
Authority: GB
Inventors: Christopher John Leslie Goss
Original assignee: Individual
Current assignee: Individual
Priority date: 1988-11-04
Filing date: 1988-11-04
Publication date: 1990-05-09
Also published as: GB8825927D0

Abstract

A method for the treatment of fruit and vegetables comprises the application to the surface of the fruit and vegetables of a dilute aqueous solution either of a bactericide or a bacteristat and a surfactant or of a bactericide having surfactant properties. The solution provides a safe and effective fruit and vegetable wash, which cleans fruit and vegetables, is active against germs, and helps remove pesticides, herbicides and fungicides, agricultural residues and atmospheric pollution. The formulation contains food approved ingredients and in working concentration in cold water is odourless, tasteless, colourless and biodegradeable.

Description

A METHOD OF TREATMENT OF FRUIT AND VEGETABLES Field of the invention This invention relates to a method of treatment of fruit and vegetables.

Backçround to the invention It is widely known that eating fruit and vegetables can seriously damage one's health and as a result of, for example, applied chemicals adhered to the surfaces of the fruit and vegetables. The applied chemicals include a whole range of agricultural and horticultural chemicals such as pesticides, fungicides, bactericides and herbicides. Many of these chemicals are not biodegradable and thus build up within the body.

By the time that fruit and vegetables arrive at the end user, they may well have been handled several times since harvesting. Bacteria such as Escherischia coli (a faecal indicator organism) and a variety of diseases and viral infections may thus be transmitted in such a manner.

The unseen toll of pesticide poisoning contained on the skins of fruit and vegetables causes an increasing number of cases of acute poisoning and it is possible that the overall scale of the problem has not yet been properly appreciated. It is accordingly an object of the present invention to provide a method of treating fruit and vegetables which overcomes the problem outlined above.

SummarY of the Invention According to the invention there is provided a method for the treatment of fruit and vegetables which comprises the application to the surface of the fruit and vegetables of a dilute aqueous solution of either a bactericide or a bacteristat and a surfactant or a bactericide having surfactant properties.

The dilute aqueous solution may either be in the form of a wash within which the fruit and vegetables are immersed, or a wipe, i.e. a cloth or tissue is impregnated with the aqueous solution.

If it is decided to utilise a bactericide having surfactant properties, the preferred materials are quaternary ararnoniurr compounds which include long-chain carbon constituents, particularly between ten and twenty atoms in the carbon chain. A suitable material is dimethylcocobenzylammonium chloride.

If a bacteristat is employed, it is preferably an alkali metal salt of propionic, sorbic or benzoic acid, such bacteristat being employed in conjunction with a chelating agent such as an alkali metal citrate.

If a bactericide is employed, it is preferably chlorophenolic bactericide, for example, 2, 4, 4, trichloro-2-hydroxy-diphenyl ether.

Preferred surfactants include polyoxyethylene sorbitan monolaurate and sorbitan monolaurate, such surfactants being used in conjunction with either a co-emulsifier such as soya bean lecithin or a surfactant "builder" such as alkali metal phosphate, eg. tetrapotass ium pyrophosphate.

Description of the Preferred Embodiments Composition A was prepared using a quaternary ammonium compound, in particular Arquad B50 produced by Akzc, Chemie of Holland. Arquad BSO is primarily a 12-carbon chain length derivative, i. e. d imethylcocobenzylammonium chloride.

The formulation of composition A in parts by weight is as follows: Arquad B50 3 parts Sodium bicarbonate 3 parts Water 94 parts The sodium bicarbonate acts as a buffering agent for the quaternary ammonium compound and ensures that the pH of the composition is maintained at a value correspondng to the maximum bactericidal activity of the quaternary ammonium compound. The use of a long chain quaternary ammonium compound ensures that it has significant surfactant properties.

Composition A is used in diluted form at a rate of 6mls per litre so that, in the diluted solution, the concentration of the quaternary ammonium compound is 0.018% by weight. The diluted composition, for example, for washing lettuce leaves or tomatoes which are dipped in the solution and then dried without the requirement of rinsing in clean water. The composition can also be used for cleaning many other fruits and vegetables. Composition A can also be used as impregnant for tissues for use in wiping, for example, apples or tomatoes, the detergent and disinfectant activity of the quaternary ammonium compound ensuring the removal of residual chemicals and bacteria from the surfaces of the fruit.

Composition B was prepared using a bacteriostat and a surfactant. It is an aqueous solution containing the following ingedients in percentage by weight: (1) Sodium propionate 3.0% (2) Sodium citrate 0.3% (3) Sorbitan monolaurate 0.5S (4) Tetrapotassium pyrophosphate 0.5S (5) Water 95.7% Sodium propionate acts as a bacteriostat; sodium citrate acts as a chelating agent to prevent the formation of alkaline earth metal salts precipitates when using tap water; sorbitan monolaurate acts as a surfactant; and tetrapotassium pyrophosphate acts as a surfactant "builder", i.e. it enhances the surface active properties of the surfactant, and also as a chelating agent for magnesium salts which will be present in hard potable water.

As an alternative to sodium propionate, it is possible to employ an equivalent amount of sodium benzoate or sodium sorbate. As an alternative to sodium citrate, it is possible to employ an equivalent amount of sodium ethylenediaminetetraacetate. Up tolM., of polyoxyethylene sorbitan monolaurate may be used in place of sorbitan monolaurate and as an alternative to the pyrophosphate, other phosphates may be employed, eg. sodium hexametaphosphate. It is possible to employ up to 1%. by weight of soya bean lecithin as a co-emulsifier with the surfactant.

As with Composition A, Composition B is used in diluted form at a rate of 6mls per litre of water. The diluted composition can be used for any of the purposes referred to above in relation to Composition A.

Composition B is active against germs, helps remove pesticides (fungicides etc.) and other agricultural residues and also helps remove atmospheric pollution. It is safe in that it contains food approved ingredients inasmuch that it is entirely based on food approved ingredients. It is colourless, tasteless and biodegradeable. It is to be used in cold water and no rinse is required.

Composition C was prepared using a bactericide and a surfactant. The bactericide is produced by Ciba Geigy under the trade mark IRGASAN DP 300 and the active constituent is 2, 4, 4- trichloro-2-hydroxy-diphenyl ether.

O.5gms of IRGASAN DP 300 were dissolved in 25mls of O.1M sodium bicarbonate solution which were then admixed with 50mls of an aqueous solution containing 0. sums of soya bean lecithin. Compositions A B and C can be effectively thickened by the addition of 0. 5% w/w of sodium carboxymethylcel lulose.

Composition C is used as descibed above at a dilution of either S0mls or lOOmls per litre of water.

Claims

CLAIMS:

1. A method for the treatment of fruit or vegetables which comprises the application to the surface of the fruit or vegetables of a dilute aqueous solution of either a bactericide or a bacteristat and a surfactant or a bactericide having surfactant properties.

2. A method according to claim 1, in which the dilute aqueous solution is in the form of a wash within which the fruit or vegetables are immersed.

3. A method according to claim 1, in which the dilute aqueous solution is applied to a cloth or tissue with which the fruit or vegetables are wiped.

4. A method according to any one of the preceding claims, in which a bactericide having surfactant properties is employed and said bactericide is a quaternary ammonium compound.

5. A method, according to claim 4, in which said quaternary ammonium compound has a carbon chain of between 10 and 20 carbon atoms.

6. A method according to any one of claims 1 to 3 in which a bacteristat is employed, said bacteristat being an alkali metal salt of propionic, sorbic or benzoic acid.

7. A method according to claim 6, in which said bacteristat is employed in conjunction with a chelating agent.

8. A method according to claim 6 or 7, in which said bacteristat is employed in conjunction with either sorbitan monolaurate or polyoxyethylene sorbitan monolaurate as surfactant.

9. A method according to any one of the claims 1 to 3, in which a bactericide is employed and said bacticide is a chlorophenolic bactericide.

10. A method for the treatment of fruit and vegetables which includes an aqueous solution of either a bactericide or bacteristat and a surfactant or a bactericide having surfactant properties, the constituents of said solution being substantially as hereinbefore described with particular reference to compositions A, B and C.