MXPA99009340A - Sanitizing composition and method - Google Patents

Abstract

The present invention is directed to a sanitizer that includes (a) a sulfonated compound selected from the group consisting of a fatty acid and esters and salts thereof;(b) a solvent for the sulfonated compound;(c) a solubilizing agent for the sulfonated compound;and (d) an antimicrobial agent. The steps used to prepare the sanitizer include:(a) contacting the sulfonated compound with the solvent;and (b) contacting the solubilizing agent with the solvent. The time between the two contacting steps is preferably no more than about 20 minutes.

Description

METHOD AND COMPOSITION SAN ITIZANTE FIELD OF THE INVENTION The present invention is directed generally to compositions and methods for sanitizing articles and specifically to compositions and methods for sanitizing using fatty acids and antimicrobial agents.

BACKGROUND OF THE I NVENTION The final rinse sanitizers are used by food processors, beverage producers, dairy processors, fermented products and the pharmaceutical industry, among others, to kill the bacteria found in the equipment. This has always been of primary importance to ensure a bacteria-free environment in the processing equipment to reduce the opportunity for contamination of food or pharmaceutical items being distributed to the general public. The common sanitizers used in this process vary in types and effectiveness. Sanitizers that use chlorine compounds have been the standard in the industry; however, such sanitizers have a number of disadvantages. Chlorine-based sanitizers can be corrosive to "equipment, decompose" at high temperatures, can be adversely affected by loads of organic dirt, and impart undesirable flavors to food or pharmaceutical items at high temperatures. Sanitizers that use iodine compounds can have many, if not all, of the same disadvantages as chlorine-based sanitizers, as well as the additional disadvantage of staining the article being sanitized. Sanitizers using peroxyacetic acid have become widely used in food processing but are being disadvantaged due to their corrosiveness in metal articles, such as stainless steel and packaging material. Peroxyacetic acid-based sanitizers are considered by many to be one of the most dangerous sanitizers on the market. Sanitizers using quaternary ammonium compounds have found only limited use due to their inability to kill certain types of bacteria. Such sanitizers are very active against gram positive, yeast and mold, but have limited effectiveness in killing gram negative bacteria. Sanitizers form relatively high foam, causing many problems in CIP Equipment. Sanitizers using chlorine dioxide require an activation step and long residence time after activation, before the chlorine dioxide becomes an effective bactericide. Sanitizers using dodecylbenzene, sulfonic acid or other similar compounds produce excessive lather or produce odors, "causing CIP problems and / or flavors.

BRIEF DESCRIPTION OF THE INVENTION The objectives of the present invention include providing a sanitizer that is highly effective in killing a wide variety of bacteria including both gram positive and negative bacteria, has a relatively low degree of corrosivity in metals, is stable to relatively high temperatures, is not impacted by loads of organic dirt, does not impart flavor to the sanitized article, does not stain the sanitized article, is relatively non-hazardous, is relatively low foaming or non-foaming, does not require activation or residence time after the activation to be effective in killing bacteria, has effective annihilating power, leaves the surfaces free of film and / or does not produce odors after sanitization.These and other objects are directed by the sanitizing composition of the present invention. provides a liquid sanitizing composition that includes: (a) no more than about 14.0% by weight (and more preferably not more than about 15.5% by weight) of at least one of a sulfonated compound selected from the group consisting of a fatty acid and esters and salts thereof; (b) a solubilizing agent for the sulfonated compound; and (c) an antimicrobial agent. To provide an effective environment for bacterial bacteria, the liquid sanitizer composition has a pH of no more than about 3.0. The sanitizer is not only highly effective in killing bacteria, but can also be relatively low foaming, non-corrosive, stable at relatively high temperatures, is not affected by organic dirt loads, neutral taste, does not stain and not dangerous to users. The sanitizer may also have effective killing power, leave film-free surfaces and produce few, if any, odors.

The sulfonated fatty acid is preferably selected from the group consisting of sulphonated oleic acids, sulfonated linoleic acids, sulfonated myristic acids and mixtures thereof. Preferably, the sulfonated fatty acid has a concentration in the sanitizing composition of no more than about 1.5 grams / liter. The antimicrobial agent can be any of a variety of bactericides, including phosphoric acid, citric acid, lactic acid, hydrochloric acid, hydroxyacetic acid, acetic acid, and esters and salts and mixtures thereof, with phosphoric acid being most preferred. citric acid and lactic acid. The antimicrobial agent has a preferred concentration in the sanitizing composition ranging from about 0.4 to about 400 grams / liter. Preferred antimicrobial agents do not require any activation step or residence time to make the agent an effective bactericide. The solubilizing agent is preferably an alcohol, such as propylene glycol, ethyl alcohol, isopropyl alcohol, hexylene glycol and mixtures thereof The preferred concentration of the alcohol in the sanitizing composition varies from about 0.02 to about 80 grams / liter. The sanitizing composition preferably does not include harmful compounds found in other sanitizers By way of example, the composition is substantially free of iodine, chlorine, peroxyacetic acid, dodecyl benzene, sulfonic acid and quaternary ammonium compounds.

The sanitizing composition may also include a solvent for the components noted above. The solvent is preferably selected from the group consisting of water, hydrogen peroxide, ethoxylated alcohols and mixtures thereof. The steps used to prepare the sanitizing composition are important for the effectiveness of the composition. The method includes the steps "of: (a) contacting the sulfonated fatty acid with a solvent for the sulfonated fatty acid, (b) contacting the alcohol with the solvent to form an intermediate sanitizing composition, wherein the time between the contact passage (a) and contact passage (b) is preferably not more than about 20 minutes The intermediate sanitizing composition can be contacted with the antimicrobial agent at an acidic pH If a too long period passes. between the additions of the sulfonated fatty acid and the alcohol, the sulfonated fatty acid can be "waxed out" of the solvent.

DETAILED DESCRIPTION The low foamed sanitizer of the present invention preferably includes a solvent, a sulfonated fatty acid and / or esters and / or salts thereof, a solubilizing agent for the sulfonated fatty acid in the solvent, and a antimicrobial agent. "Preferably, the pH of the sanitizer is acid, more preferably it is no more than about pH 3 and more preferably ranges from about pH 1 to about 2. The solvent (or carrier) can be any solvent (or carrier), preferably not toxic and non-hazardous, for the sulfonated fatty acid and the antimicrobial agent .. Preferred solvents * (and / or carriers) include water, hydrogen peroxide, propylene glycol, isopropyl alcohol and mixtures thereof, with water and propylene glycol being most preferred. The sulfonated fatty acid can be any low-foam compound having one or more sulfo groups connected to a carbon or nitrogen atom. The length of the chain of the sulfonated compound is preferably relatively short to allow the sulfonated compound to pass through the cell wall of the bacteria. Most preferably, the chain length is sufficiently short to produce a molecular weight of the sulfonated compound of about 1 72 daltons or less. Preferred sulfonated fatty acids include sulfonated oleic acid, sulfonated linoleic acid, sulfonated myristic acid, toluene sulfonic acid, and mixtures thereof. Although the sanitizer may include esters and / or salts of sulphonated fatty acids instead of a sulfonated fatty acid, sulfonated fatty acids and salts thereof are most preferred. The total concentration of the sulfonated fatty acid, esters, and salts of fatty acids is important for the performance of the sanitizer. Preferably, the concentration (before the dilution to be used) is no more than about 14.0% by weight and more preferably ranges from about 6 to about 12% by weight and most preferably from about 9 to about 15.5% by weight. weight, or preferably no more than about 14.0 g / l and more preferably ranges from about 6 to about 12 g / f and most preferably from about 10.0 to about 1-1.5 g / l. The end use concentration is preferably not more than about 0.07% by weight (ie, no more than about 0.7 g / l) and more preferably ranges from about 0.01 to about 0.03% by weight (i.e., varying from about 0.01 to about 0.03 g / l). As will be appreciated, the "end use" concentration refers to the concentration of the select component during sanitization. In some applications, the sanitizer is diluted with solvent or additional carrier (eg, water) before sanitization. The common dilution ratio of the sanitizer to the solvent or carrier is at least about 0.2% and more commonly ranges from about 0.3% to about 0.5%. The solubilizing agent can be any compound that makes the fatty acid, fatty ester or salt of fatty acid more soluble in the solvent. Preferred solubilizing agents are short chain alcohols having a molecular weight of no more than about 46 daltons. More preferred agents include propylene glycol, ethyl alcohol, isopropyl alcohol, hexylene glycol, and mixtures thereof. The molar ratio of the solubilizing agent to the sulfonad compound preferably ranges from about 4: 1 to about 2: 1 and more preferably from about 3 to about 2.2: 1.

Such molar proportions produce a preferred concentration (before dilution to be used) of the solubilizing agent in the sanitizer ranging from about 10 to about 80 g / l and more preferably from about 30 to about 60 g / l, or from about 1 to about about 8% by weight, more preferably from about 3.5% by weight to about 6.5% by weight, and most preferably from about 4.5% by weight to about 5.5% by weight. The end-use concentration varies, preferably, from about 0.02 to about 0.40 g / f (ie, from about 0.001 to about 0.04 wt%) and most preferably from about 0.06 to about 0.30 g / l (ie from about 0.001 to about 0.03% by weight). The antimicrobial agent can be any of a variety of bactericides. Preferred bactericides include phosphoric acid, citric acid, lactic acid, hydrochloric acid, hydroxyacetic acid, acetic acid, and esters and salts thereof, with food grade bactericides being highly preferred, such as phosphoric acid, citric acid and lactic acid. and esters and salts thereof. While not wishing to be bound by any theory, it is believed that the antimicrobial agent and the fatty compound operate synergistically to cause bacterial killing. It is believed that the gaseous compound penetrates and causes swelling of the cell wall. The antimicrobial agent is able to pass through the hindered cell wall, thereby causing cell wall rufaction and death of the bacterium. The end-use concentration of the antimicrobial agent is important for the effectiveness of the sanitizer. Preferably, the molar ratio between the sulfonated compound and the antimicrobial agent ranges from about 1: 1 to about 3: 1 and more preferably from about 1.5: 1 to about 2: 1, which produces a preferred concentration (prior to the dilution to be used) ranging from about 20 to about 40% by weight (or from about 200 to about 400 g / l) and a more preferred concentration ranging from about 25 to about 35% by weight (or from about 250 to about 350 g / l). The end-use concentration varies, preferably, from about 0.04 to about 0.2 & by weight (or from about 0.40 to about 2 g / l) and more preferably from about 0.05 to about 0. 1 8% by weight (or from about 0.5 to about 1.75 g / l). The regulation of the time of the steps to prepare the sanitizer is important for the effectiveness of the sanitizer in the death of microbes. The various components can be added to the solvent in any sequence (for example, the sulphonated compound can be added sooner or later, or at the same time as the solubilizing agent), provided that the sulphonated compound and the sol ubylating agent are added in close proximity. temporal proximity or not of the other. Preferably, the sulphonated compound and the solubilizing agent are added within 20 minutes of each other, more preferably within about 10 minutes, and most preferably within about 5 minutes. If too long a period elapses between the addition of the sulfonated compound and the solubilizing agent, the sulfonated compound can "wax out" (or precipitate out) of the solvent over time. The antimicrobial agent can be "added at any time during the preparation of the sanitizer." The concentrated sanitizer can be further diluted before use.

EXPERI M ENTO 1 An experiment was conducted to determine the effectiveness of a sanitizer according to the present invention to kill bacteria. A sanitizer was prepared using the following components: (a) 25% by weight of aqueous phosphoric acid (75% by weight of solution); (b) 5% by weight of propylene glycol; (c) 2% by weight of ethanol (normal grading 1 00); (d) 6 wt% sulfonated oleic acid; and (e) 62% by weight of water. Staphylococcus aureus and Pseudomonas aeruginosa were added to hard water in varying concentrations. A use concentration of 29.4 ml of the sanitizer was used per 1 1 .35 I of hard water. At a bacteria concentration of 1 50 ppm in the hard water, the sanitizer had a death rate of 99.999% and, at a bacteria concentration of 250 ppm in the water, the sanitizer had a death rate of EXPERIMENT 2 Another experiment was conducted to determine the effectiveness of a sanitizer using higher concentrations of phosphoric acid and oleic acid sulfonated to kill bacteria. A sanitizer was prepared using the following components: (a) 40% by weight of aqueous phosphoric acid (75% by weight of solution); (b) 5% by weight of propylene glycol; (c) 2% by weight of ethanol (normal grading 1 00); (d) 14% by weight of sulfonated oleic acid; and (e) 39% by weight of water. Staphylococcus aureus and Pseudomonas aeruginosa were added to separate batches of hard water at concentrations of 1 50 ppm and 250 ppm. A use concentration of 29.4 ml of the sanitizer was used per 1 1 .35 I of hard water. At both concentrations, the proportion of death of bacteria was approximately 99.999%. After two weeks, the preparation became unstable in a storage at 37.78 ° C and the experiment was discontinued.

EXPERI MENT 3 Another experiment was carried out to determine the effectiveness of a sanitizer using higher concentrations of phosphoric acid and oleic acid sulphate to kill bacteria. A sanitizer was prepared using the following components: (a) 35% by weight of aqueous phosphoric acid (75% by weight of solution); (b) 5% by weight of propylene glycol; (c) 2% by weight of ethanol (normal grading 1 00); (d) 10% by weight of sulfonated oleic acid; and (e) 48% by weight of water. Staphylococcus aureus and Pseudomonas aeruginosa were added to agar in varying concentrations. A use concentration of 29.4 ml of sanitizer was used per 1 1 .35 l of hard water. At concentrations of bacteria of 1 50 and 250 ppm in hard water, the sanitizer had a death rate of 99.999%.

EXPERI MENT 4 The following experiments were run against a standard of Gram-positive and Gram-negative bacteria to demonstrate the synergistic effect of phosphoric acid and sulfonated oleic acid to kill such bacteria. Each organism was grown to 2-6 x 1 06 organisms per cc of broth. Death proportions were run using a standard method "AOATC" Weber & Black Chalange Specifically, one cc of bacteria is placed in 99 ml of sanitizing solution (200 ppm) held in solution for 30, 60, 1 20 seconds. In each interval a 1 cc sample was taken and then neutralized in 9 ml of a 1% sodium bicarbonate solution. A cc was then removed from the neutralizing solution and plated. After 48 h of incubation, the results were read. Sanitizing solutions included 200 ppm of phosphoric acid alone, 200 ppm of sulphonated oleic acid alone, and 200 pp of each of phosphoric acid and sulphonated oleic acid. The results are presented below.

M ETHOD AND SANITATION COMPOSITION As can be seen from the above tables, sanitizing solutions containing either phosphoric acid alone or sulfonated oleic acid alone, had significantly lower death rates both against gram negative and gram positive bacteria, than a sanitizing solution containing both sulfonated oleic acid and phosphoric acid. Accordingly, the joint use of oleic acid sulfonad and phosphoric acid provide surprising and unexpected synergistic results to kill bacteria.

While various embodiments of the present invention have been described in detail, it is evident that modifications and adaptations of these modalities will occur to those skilled in the art. However, it should be expressly understood that such modifications and adaptations are within the scope of the present invention, as set forth in the following claims.

Claims (25)

1. REVIVALATION IS
2. 1 . A liquid sanitizing composition, comprising: Xa) a solvent; (b) not more than about 14% by weight of a sulfonated compound which is at least one of a sulfonated fatty acid, and esters and salts thereof; (c) a solubilizing agent for the sulfonated compound in the solvent; and (d) an antimicrobial agent, wherein the liquid sanitizing composition has a pH of no more than about 3.0. The sanitizing composition of claim 1, wherein the sulphonated fatty acid is selected from the group consisting of a sulfonated oleic acid, a sulfonated linoleic acid, and a sulfonated myristic acid and mixtures thereof.
3. 3. The sanitizing composition of claim 1, wherein the concentration of the sulfonated compound in the solvent is not more than about 1-1.5 g / l.
4. 4. The sanitizing composition of claim 1, wherein the antimicrobial agent is selected from the group consisting of phosphoric acid, citric acid, lactic acid, hydrochloric acid, hydroxyacetic acid, acetic acid, and esters and salts and mixtures thereof. the same.
5. 5. The sanitizing composition of claim 1, wherein the concentration of the antimicrobial agent in the composition is at least about 0.4 g / l.
6. 6. The sanitized composition of claim 1, wherein the composition comprises at least about 0.04% by weight of the antimicrobial agent. The sanitizing composition of claim 1, wherein the solubilizing agent comprises an alcohol. The sanitizing composition of claim 6, wherein the alcohol is selected from the group consisting of propylene glycol, ethyl alcohol, isopropyl alcohol, hexylene glycol and mixtures thereof. The sanitizing composition of claim 6, wherein the concentration of the alcohol in the solvent varies from about

   0. 02 to approximately 80 g / l. 10. The sanitizing composition of claim 1, wherein the composition comprises from about 0.001 to about 8% by weight of the solubilizing agent. eleven . The sanitizing composition of claim 1, wherein the composition is substantially free of iodine. The sanitizing composition of claim 1, wherein the composition is substantially free of chlorine. 13. The sanitizing composition of claim 1, wherein the composition is substantially free of peroxyacetic acid. 14. The sanitizing composition of claim 1, wherein the composition is substantially free of dodecylbenzene and sulfonic acid. 5. A sanitizing composition, comprising (a) not more than about 14% by weight of an oleic acid. sulfonated; (b) a solubilizing agent selected from the group consisting of propylene glycol, ethyl alcohol, isopropyl alcohol and mixtures thereof; and (c) an antimicrobial agent selected from the group consisting of phosphoric acid, citric acid, lactic acid and esters and salts and mixtures thereof. 16. A method for sanitizing an object, comprising: contacting the object with an antimicrobial acid composition comprising no more than about 14% by weight of a sulphonated fatty acid or ester or salt thereof, an antimicrobial agent and an antimicrobial agent. alcohol. The method of claim 16, wherein the fatty acid is sulfonated oleic acid. The method of claim 16, wherein the antimicrobial agent is selected from the group consisting of phosphoric acid, citric acid, lactic acid, and esters and salts and mixtures thereof. 9. The method of claim 16, wherein the aqueous composition comprises from about 0.04 to about 40% by weight of the antimicrobial agent. 20. The method of claim 16, wherein the alcohol is selected from the group consisting of propylene glycol, ethyl alcohol, isopropyl alcohol and mixtures thereof.

   twenty-one . The method of claim 16, wherein the aqueous composition comprises from about 0.001 to about 8% by weight of the alcohol. 22. A method for preparing a sanitizing composition, comprising: (a) contacting a sulfonated fatty acid or ester or salt thereof with a sulfonated fatty acid solvent, (b) contacting an alcohol with the solvent to form an intermediate sanitizing composition, wherein the time between the contact passage (a) and the contact contact passage- '(b) is not more than about 20 minutes 23. The method of claim 13, further comprising (c) contacting the intermediate sanitizing composition with an antimicrobial agent at an acid pH 24. The method of claim 14, wherein the solvent is selected from the group consisting of water, hydrogen peroxide, ethoxylated alcohols, and mixtures thereof 25. The method of claim 14, wherein the time between the contact passage (a) and the contact passage (c) is not more than about 10 minutes.