EP4176034B1

EP4176034B1 - Composition

Info

Publication number: EP4176034B1
Application number: EP21732328.6A
Authority: EP
Inventors: Sarmistha BISWAS; Udayan Majumdar; Gaurav Pathak; Jayashree Anantharam Vadhyar
Original assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Current assignee: Unilever Global IP Ltd; Unilever IP Holdings BV
Priority date: 2020-07-03
Filing date: 2021-06-17
Publication date: 2025-08-06
Anticipated expiration: 2041-06-17
Also published as: CN115735002A; EP4176034A1; WO2022002607A1; EP4176034C0; BR112022025034A2

Description

The present invention relates to a composition for cleaning comestibles, in particular, fruit and vegetables.
WO 2018/044840 discloses a method of reducing microbes on a food surface and a hard surface. It discloses antimicrobial composition comprising two cationic surfactant and one of the cationic surfactants is a quaternary ammonium cation. It further discloses that the composition may have a second cationic surfactant, an antibiotic and an amino poly-carboxylic acid.
Despite the prior art, there remains a need for improved compositions for cleaning comestibles such as fruit and vegetables. In particular, there is a need to have a composition which can clean uncut fruit or vegetables of bacteria and viruses or such like without leaving any residues.
Accordingly, and in a first aspect, there is provided a composition comprising 0.1 to 2% wt. non-ionic surfactant, a vicinal diol and a quaternary ammonium salt, for cleaning comestibles wherein the diol has 7 to 14 carbon atoms.
Typically, consumers procure comestibles from a market and wash them with water before consumption. However, washing with water alone does not remove microbes efficiently. One way to improve cleaning efficacy, in particular, by removing microbes, is to use a cleaning composition comprising surfactant and antimicrobial agent. It is always desired to have improved cleaning compositions for providing enhanced antimicrobial efficacy.
Often efficacy of such compositions depends on the amount of actives, i.e., surfactant, antimicrobial agents etc. present in the composition. Low amount of the actives may lead to insufficient cleaning. Whereas excess amount of the actives may leave residue of the actives on the comestibles, which is not preferred by the consumers. Therefore, it is also desired that the cleaning compositions provide enhanced antimicrobial efficacy, yet do not leave residue on the comestibles.
We have surprisingly found that lowering the amount of surfactant can provide better antimicrobial efficacy in compositions also comprising a diol and a quaternary ammonium salt.
The composition comprises 0.1 to 2% wt. non-ionic surfactant. Preferably, the surfactant is present at from 0.5 to 1.8% wt., more preferably 0.5 to 1.5% wt. of the composition.
Non-ionic surfactants generate less foam than anionic surfactants. Non-ionic surfactants are characterized by the presence of a hydrophobic group and an organic hydrophilic group and are typically produced by condensation of an organic aliphatic or alkyl aromatic hydrophobic compound with ethylene oxide.
Preferably, the non-ionic surfactant comprises alkoxylated alkanols in which the alkanol is of 9 to 20 carbon atoms and wherein the number of molecules of alkylene oxide (of 2 or 3 carbon atoms) is from 5 to 20. Of such materials, it is preferred to use those wherein the alkanol is a fatty alcohol of 9 to 11 or 12 to 15 carbon atoms and which contain from 5 to 8 or 5 to 9 alkoxy groups per mole.
Also preferred are paraffin-based alcohols (e.g. non-ionic surfactants from Huntsman or Sassol). Preferably the non-ionic surfactant is selected from an alkoxylated linear alcohol, more preferably an ethoxylated linear alcohol.
Exemplary of such compounds are those in which the alkanol is of 10 to 15 carbon atoms and which contain about 5 to 12 ethylene oxide groups per mole, e.g. Neodol^™ family, Tergitol 15-S-7 etc. These are condensation products of a mixture of higher fatty alcohols averaging about 12 to 15 carbon atoms with about 9 moles of ethylene oxide. The higher alcohols are primary alkanols.
Another subclass of alkoxylated surfactants which may be used contain a precise alkyl chain length rather than an alkyl chain distribution of the alkoxylated surfactants.
Typically, these are referred to as narrow range alkoxylates. Examples of these include the Neodol^™-1 series of surfactants.
Other useful non-ionic surfactants are represented by the commercially well-known class of non-ionic surfactants sold under the trademark Plurafac^™ from BASF. The Plurafac^™ are the reaction products of a higher linear alcohol and a mixture of ethylene and propylene oxides, containing a mixed chain of ethylene oxide and propylene oxide, terminated by a hydroxyl group. Examples include C13 to C15 fatty alcohols condensed with 6 moles ethylene oxide and 3 moles propylene oxide, C13 to C15 fatty alcohol condensed with 7 moles propylene oxide and 4 moles ethylene oxide, C13 to C15 fatty alcohol condensed with 5 moles propylene oxide and 10 moles ethylene oxide or mixtures of any of the above.
Another group of non-ionic surfactants are commercially available as Dobanol^™ which is an ethoxylated C fatty alcohol with an average of 7 moles ethylene oxide per mole of fatty alcohol.
Preferably the non-ionic surfactant comprises alkyl polyglycosides (APG). Alkyl polyglycosides are compounds having formula: R1O(R2O)b(Z)a, wherein R1 is a alkyl radical, having from about 1 to about 30 carbon atoms; R2 is an alkylene radical having from 2 to 4 carbon atoms; Z is a saccharide residue having 5 or 6 carbon atoms; b is a number having a value from 0 to about 12; and a is a number having a value from 1 to about 6 (the degree of polymerization). Due to the method by which they are synthesized, alkyl polyglycosides are generally present as mixtures of alkyl polyglycosides having varying amounts of carbon atoms in the alkyl radical and varying degrees of polymerization. Thus, when referring to alkyl polyglycosides, the alkyl radical is generally referred to as having a range of carbon atoms (e.g. C4/22 referring to a range of alkyl radicals having from 4 to 22 carbon atoms) and the degree of polymerization is generally referred to as the average degree of polymerization of the mixture.
Preferably the non-ionic surfactant comprises alkyl polyglucoside surfactant. Example of such surfactants are decyl glucoside, lauryl glucoside, myristyl glucoside.
Other suitable non-ionic surfactants are sorbitan mono and tri alkanoic acid containing 10 to 20 carbon atoms condensed with ethylene oxide. Examples of such compounds are polyoxyethylene (4) sorbitan monolaurate, polyoxyethylene (20) sorbitan trioleate and polyoxyethylene (20) sorbitan tristearate.
Another example of suitable non-ionic surfactant is polyethylene glycol derivative of hydrogenated castor oil.
The composition comprises a vicinal diol. A vicinal diol has a pair of hydroxy groups in the 1 and 2 position on a carbon chain. The diol has from 7 to 14 carbon atoms.
Preferably the diol is selected from 1,2 heptanediol, 1, 2 octanediol, 1,2 nonanediol, 1,2 decanediol, 1,2 dodecandiol, 1,2 tetradecanediol and combination thereof. Preferably, the diol has from 8 to 10 carbon atoms. The most preferred diol is 1, 2-octanediol.
Preferably, the diol is present at from 0.01 to 3.0% wt. of the composition. More preferably, the diol is present at from 0.1 to 1.0% wt. of the composition and most preferably from 0.3 to 0.8% wt. of the composition.
The composition comprises a quaternary ammonium salt. Preferably the quaternary ammonium salt is present at from 0.05 to 5.0% wt. of the composition. More preferably the ammonium salt is present at from 0.1 to 4.0% wt., even more preferably 0.5 to 3.0 % wt. of the composition.
Quaternary ammonium salts have the general formula: R1R2R3R4N+X- wherein R1 is a C12 to C18 alkyl group, each of R2, R3 and R4 independently is a C1 to C3 alkyl group and X is an inorganic anion. R1 is preferably a C14 to C16 straight chain alkyl group, more preferably C16. R2, R3 and R4 are preferably methyl groups. The inorganic anion (X-) is preferably chosen from halide, sulphate, bisulphate or hydroxide.
For the purposes of this invention, a quaternary ammonium hydroxide is considered to be a quaternary ammonium salt. More preferably the anion is a halide ion or sulphate, most preferably a chloride or sulphate. Cetyl-trimethylammonium chloride is a specific example of a suitable compound and commercially abundantly available.
Suitable quaternary ammonium cationic surfactant is the class of benzalkonium halides, also known as alkyl dimethyl benzyl ammonium halides. The most common type being benzalkonium chloride, also known as alkyl dimethyl benzyl ammonium chloride (or ADBAC)
Example of suitable quaternary ammonium includes Cetyl-trimethyl-ammonium Chloride, Cetyl-trimethyl-ammonium Bromide, Tetradecyl-trimethyl-ammonium Chloride, Dodecyl-trimethyl-ammonium Chloride, Stearyl-trimethyl-ammonium Chloride, Octadecyltrimethyl- ammonium Chloride, Dodecylpyridinium Chloride, Cetylpyridinium Chloride, Benzalkonium Chloride, Tetrabutylammonium Chloride, Tetraheptyl-ammonium Chloride, 1,3-Decyl-2-methyl-imidazolium Chloride, 1-Hexadecyl-3-methyl-imidazolium Chloride, Didecyl-dimethyl-ammonium Bromide, Didecyl-dimethyl-ammonium Chloride.
Preferably, the quaternary ammonium salt selected from benzalkonium chloride, benzethonium chloride, cetalkonium chloride, cetylpyridinium chloride and tetraethyl ammonium bromide and mixtures thereof. Most preferred quaternary ammonium salt is benzalkonium chloride.
Preferably, the composition comprises a citrate salt. Preferably, the citrate salt is present at from 0.5 to 5.0% wt. of the composition, more preferably from 0.75 to 4% wt., even more preferably 1.0 to 3.0% wt. by weight of the composition. A preferred citrate salt is sodium citrate.
The composition may comprise a hydrotrope. Preferably, the hydrotrope is present at from 0.1 to 5.0% wt. of the composition. More preferably the hydrotrope is present at from 1.0 to 3.0% wt.
Hydrotrope are typically low molecular weight, water-soluble or water-miscible organic compounds such as C1 to C5 monohydric alcohols (such as ethanol and n- or i-propanol); C2 to C6 diols (such as monopropylene glycol and dipropylene glycol); C3 to C9 triols (such as glycerol); polyethylene glycols having a weight average molecular weight (Mw) ranging from about 200 to 600; C1 to C3 alkanolamines such as mono-, di- and triethanolamines; and alkyl aryl sulfonates having up to 3 carbon atoms in the lower alkyl group (such as the sodium and potassium xylene, toluene, ethylbenzene and isopropyl benzene (cumene) sulfonates).
Suitable hydrotrope include short carbon chain glycol like ethylene glycol, mono propylene glycol, di propylene glycol. The most preferred hydrotrope is 1-2, propanediol.
Preferably the composition is an aqueous composition and comprises from 50 to 95% wt. water, more preferably from 60 to 90% wt., even more preferably 70 to 85% wt. water.
Preferably, the composition is in a single dose format. Single dose formats include compositions stored and packaged in sachets. In single dose format, preferably, the composition is contained in a water-soluble pouch, which dissolve in contact with water releasing the composition in water.
In a second aspect there is provided a method for cleaning a comestible by diluting a composition according to the first aspect in water, washing said comestible in the diluted mixture of the composition in water, and then rinsing, wherein the composition is diluted from 1:5 to 1:200 in water.
The diluted composition is used to wash the edible object and it is preferred that the edible object is not cut before putting into the wash composition. Preferably, the edible object is left in the wash composition for from 5 minutes to 2 hours before being removed, optionally rinsed and drained. Alternatively, the composition may be packed in a bottle with a spray-head. In such case, a consumer directly sprays the composition on comestibles and wipe it with a tissue or a piece of cloth.

EXAMPLES

The following formulations are prepared for cleaning fruit and vegetables. Table 1

Ingredient Formulation A Formulation 1

1,2 Octanediol 0.5 0.5

Benzalkonium Chloride 1 1

Non-ionic surfactant 3 1.5

Sodium Citrate 2 2

1, 2-propanediol 2 2

Water To 100 To 100
Formulation 1 is a composition according to the invention, whereas formulation A is a comparative.

Test method for evaluating antimicrobial efficacy:

Antimicrobial efficacy was tested following European Suspension Test (EST) or EN 1276 B.
The tests were conducted on following bacteria:

Escherichia coli ATCC 10536 (Gram-negative)
Pseudomonas aeruginosa ATCC 15442 (Gram-negative)

A 24-hour old growth or culture of bacteria was taken, and the bacterial cells were suspended in a solution to obtain 10⁸ colony forming units/ml (CFU/ml), based on a 620 nm optical density (OD) calibration chart (0.8 OD at 620 nm for Escherichia coli and 0.5 OD at 620 nm for Pseudomonas aeruginosa).
For testing a formulation, it was diluted to the required concentrations in water at 37°C.
Eight millilitres (ml) of the diluted formulation was mixed with a previously mixed 1 ml of test bacterial culture with 1 ml of 0.3% or 3.0% (w/v) BSA or bovine serum albumin (protein, also called as soil load). The contact time was monitored by a stopwatch.
After the specified contact time, 1 ml of the above mixture (of total volume 10 ml) was immediately neutralized in with suitable buffer solutions containing neutralizers as specified in the protocol.
This neutralized buffer solution was diluted to get a countable bacterial number and plated on tryptic soy agar in duplicates for a statistically valid 30 to 300 colonies of bacteria on a single plate.
In case of control, 1 ml of the test culture was mixed with 1 ml of 0.3% BSA and 1 ml of 3.0% BSA added to 8 ml hard water and were serially diluted and plated on TSA. The plates were incubated at 37°C for 48 hours, and the residual colonies were counted.
The reduction of bacteria was calculated in log colony forming units/ml (Log CFU/ml). A log of the "Control" or input level of bacteria was calculated, and similarly a log value of the number of bacteria residuals in the samples containing the formulations under test was calculated. The log reduction value was calculated by subtracting the residual bacteria of each formulation from the input value. The higher the value means more reduction of bacteria
Test results are summarized in below table: Table 2

Test Formulation A Formulation 1

Reduction of (Log10) E coli 3.72 > 5.3

Reduction (Log 10) P aeruginosa 0.46 1.01
Table 2 shows that composition 1 removes bacteria more efficiently compared to formulation A. From the examples it is evident that contrary to expectations, the use of a lower amount of a non-ionic surfactant meant better cleaning of the food products.

Claims

A composition for cleaning comestibles comprising 0.1 to 2% wt. non-ionic surfactant, a vicinal diol and a quaternary ammonium salt, wherein the diol has 7 to 14 carbon atoms,
A composition according to claim 1 or 2 wherein the diol is present at from 0.01 to 3.0% wt. of the composition.
A composition according to any preceding claim wherein the diol has from 7 to 10 carbon atoms.
A composition according to any preceding claim wherein the diol is 1, 2-octanediol.
A composition according to any preceding claim wherein the quaternary ammonium salt is present at from 0.05 to 5.0% wt. of the composition.
A composition according to any preceding claim wherein the quaternary ammonium salt is selected from benzalkonium chloride, benzethonium chloride, cetalkonium chloride, cetylpyridinium chloride and tetraethyl ammonium bromide and mixtures thereof.
A composition according to any preceding claim comprising a citrate salt.
A composition according to any preceding claim comprising a hydrotrope selected from C1 to C5 monohydric alcohol, C2 to C6 diols, C3 to C9 triols, polyethylene glycol having a weight average molecular weight ranging from about 200 to 600, C1 to C3 alkanolamine and alkyl aryl sulphonates having up to 3 carbon atoms in the lower alkyl group.
A composition according to claim 8 wherein the hydrotrope is selected from ethylene glycol, mono-propylene glycol, di-propylene glycol, glycerol and 1-2, propanediol.
A composition according to any preceding claim in a single dose format.
A method for cleaning a comestible by diluting a composition comprising 0.1 to 2% wt. non-ionic surfactant, a vicinal diol having 7 to 14 carbon atom and a quaternary ammonium salt in water, washing said comestible in the diluted mixture of the composition in water, and then rinsing, wherein the composition is diluted from 1: 5 to 1:200 by wt. in water.