Naturally-derived surface sanitizer and disinfectant

Abstract

Food processing equipment, food contact surfaces, and non-food contact surfaces are sanitized or disinfected using an acid-anionic surfactant solution that has efficacy in hard water, is non-corrosive, and is stable at elevated temperatures. The sanitizing/disinfecting solution is prepared as a highly concentrated liquid and diluted to end use concentrations prior to application to food processing equipment or food or non-food contact surfaces. Efficacy in hard water is important for sanitizers and disinfectants that are diluted by the end user using potentially hard water. Stability at elevated temperatures is important for long-term storage and transportation. The diluted sanitizing/disinfecting solution exhibits strong antimicrobial activity against gram positive and gram negative bacteria even when dilated in hard water. The sanitizing/disinfecting solution exhibits low toxicity to humans and the environment since it is prepared from low toxicity ingredients that are readily biodegradable.

Claims

1. A sanitizing and disinfecting solution composition comprising a concentrate composition and dilution water, wherein the concentrate composition comprises: citric acid at a concentration of about 10% to about 40% by weight; capric acid at a concentration of about 0.1% to about 5% by weight; lauryl sulfate at a concentration of at least 5% weight; isopropanol at a concentration of about 1% to about 20% by weight; and water at a concentration of at least 10% by weight, wherein the dilution water comprises at least 300 ppm hardness ions; and the sanitizing and disinfecting solution composition composes the concentrate composition and the dilution water in a ratio of 1 part of the concentrate composition and 9 parts of the dilution water to 1 part of the concentrate composition to 127 parts of the dilution water.

2. The sanitizing and disinfecting solution composition of claim 1, wherein the sanitizing and disinfecting solution composition comprises the concentrate composition and the dilution water in a ratio of 1 part of the concentrate composition and 9 parts of the dilution water to 1 part of the concentrate composition to 59 parts of the dilution water.

3. The sanitizing and disinfecting solution composition of claim 1, wherein the sanitizing and disinfecting solution composition comprises the concentrate composition and the dilution water in a ratio of 1 part of the concentrate composition and 63 parts of the dilution water to 1 part of the concentrate composition to 127 parts of the dilution water.

4. The sanitizing and disinfecting solution composition of claim 1, wherein the concentrate composition has a pH from 1.2 to 5.

5. The sanitizing and disinfecting solution composition of claim 1, wherein the sanitizing and disinfecting solution composition has a pH from 1.8 to 4.

6. The sanitizing and disinfecting solution composition of claim 1, wherein the sanitizing and disinfecting solution composition has a pH from 2 to 3.

7. The sanitizing and disinfecting solution composition of claim 1, comprising: citric acid at a concentration of about 0.01% to about 4% by weight; capric acid at a concentration of about 0.0001% to about 0.5% by weight; lauryl sulfate at a concentration of about 0.005% to about 3% weight; and isopropanol at a concentration of about 0.001% to about 2% by weight.

8. The sanitizing and disinfecting solution composition of claim 1, comprising: citric acid at a concentration of about 0.021% to about 3% by weight; capric acid at a concentration of about 0.001% to about 0.2% by weight; lauryl sulfate at a concentration of about 0.0105% to about 1.2% weight; and isopropanol at a concentration of about 0.002% to about 0.7% by weight.

Description

DETAILED DESCRIPTION OF THE INVENTION

(1) The present invention pertains to the use of sanitizing and disinfecting formulations on food and non food contact surfaces and which are stable and have high tolerance to hard water (e.g., water having at least 300 ppm hardness ions such as calcium and magnesium, and especially water having at least 500 ppm hardness ions). The invention applies to all types of food and non-food contact surfaces such as food processing equipment, tables, countertops, cutting boards, inanimate medical surfaces (e.g., examination tables, lights, equipment), and other general surfaces found in healthcare, industrial, commercial, and household settings. Of critical importance is the tolerance to hard water since that allows end-users of the product to dilute the concentrated sanitizing/disinfecting solution in regular tap water and maintain excellent efficacy (cleaning and antimicrobial properties). In addition, the use of critical concentrations of organic alcohol provides stability during storage at elevated temperatures, which is important for both short- and long-term storage of solutions.

(2) The sanitizers and disinfectants are comprised of an organic acid, a naturally-derived anionic surfactant, a natural fatty acid, and an organic alcohol. The organic acid and anionic surfactant provide strong antimicrobial properties necessary for food and non-food contact surface sanitizers and disinfectants. The fatty acid provides greatly improved efficacy in hard water and also reduces the foaming properties inherent with an anionic surfactant. A critical concentration of at least about 1 wt % of the organic alcohol provides elevated temperature stability to the formulations. Sodium sulfate or sodium bisulfate can be optionally included to further increase the efficacy in hard water. An essential oil can be optionally included to add a natural scent to the sanitizer/disinfectant.

(3) All ingredients in the formulations are naturally derived (i.e., found in nature, found naturally in the human body, and/or undergone limited chemical modification [e.g., saponification or sulfation of a fatty acid]) and exhibit low human and environmental toxicity at end-use concentrations. The organic acid can be provided by one or more (e.g., combinations) of the following natural organic acids: citric acid, fumaric acid, humic acid, acetic acid, or ascorbic acid. Other similar natural organic acids can also be used. The concentrated liquid sanitizer/disinfectant formulation contains at least about 10 wt % of one or more natural first organic acids sufficient to provide a solution pH of from about 1.2-5.0, e.g., from about 10-40 wt % of such one or more natural first organic acid, preferably 15-35 wt %, and most preferably 21-30 wt %. Upon dilution to end-use concentrations, the diluted solution may contain, e.g., 0.01-4.0 wt % of the organic acid, preferably, 0.015-3.5 wt %, and most preferably, 0.021-3.0 wt %.

(4) A naturally-derived, sulfated fatty acid (e.g., sodium lauryl sulfate) is used as the anionic surfactant. The concentrated liquid sanitizer/disinfectant formulation contains at least about 5 wt %, e.g., 5-30 wt %, of the anionic surfactant, preferably 8-20 wt %, and most preferably 10.5-12 wt %. Upon dilution to end-use concentrations, the diluted solution contains 0.005-3.0 wt % anionic surfactant, preferably, 0.008-2.0 wt %, and most preferably, 0.0105-1.2 wt %. The sulfated fatty acid in a particular embodiment comprises a C6-C18 alkyl sulfate, and in a more specific embodiment a C8-C14 alkyl sulfate. One or more (e.g., combinations) of any natural sulfated fatty acid (e.g., sodium lauryl sulfate, sodium eaprylyl sulfate) can be used.

(5) The monocarboxylic fatty acid cars be provided by one or more (e.g., combinations) of the natural organic fatty acids, and in particular one or more saturated or unsaturated C6-C18 monocarboxylic acids. In a particular embodiment, the fluty acids can be provided by one or more of the following natural organic fatty acids: caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, gamma-linolenic acid, hexadecatrienoic acid, alpha-linolenic acid, pinolenic acid, or stearidonic acid. Other similar natural fluty acids can also be used. The monocarboxylic fatty acid employed is distinct from the one or more natural first organic acids sufficient to provide a solution pH of from about 1.2-5.0, as such fatty acids are typically not capable of themselves providing such low pH. The concentrated liquid sanitizer/disinfectant formulation contains at least about 0.1 wt %, e.g., 0.1-5 wt % monocarboxylic fatty acid, preferably 0.5-3 wt %, and most, preferably 1-3 wt %. Upon dilution to end-use concentrations, the diluted solution may contain, e.g., 0.0001-0.5 wt % monocarboxylic fatty acid, preferably, 0.0005-0.3 wt %, and most preferably, 0.001-0.2 wt %.

(6) The organic alcohol can be provided by any organic alcohol, with ethanol and isopropanol being common examples. The concentrated liquid sanitizer/disinfectant formulation contains at least about 1 wt %, e.g., about 1-20 wt % alcohol, preferably 2-10 wt %, and most preferably 3-10 wt %. Upon dilution to end-use concentrations, the diluted solution may contain, e.g., 0.001-2 wt % alcohol, preferably, 0.0015-1.5 wt %, and most preferably, 0.002-0.7 wt %.

(7) The concentrated solution is formulated to have a old of from about 1.2 to 5, as a pH of greater than 5 results in a formulation that has poor antimicrobial properties, while a pH of less than about 1.2 results in strong irritating properties. Optionally, the pH of the resulting solution can be adjusted with a buffering agent, such that the pH of the final, diluted sanitizer/disinfectant solution remains under 5.0 (preferably from 1.8 to 4.0, most preferably 2.0-3.0) upon dilution since antibacterial efficacy is decreased as pH increases. The buffering agent can be selected born one of the following basic neutralizing agents: calcium carbonate, magnesium carbonate, potassium carbonate, potassium bicarbonate, sodium carbonate, or sodium bicarbonate. Alternatively, a combination of the organic acid, any sodium, potassium, magnesium, or calcium salt form of the organic acid, and/or one of the previously listed basic neutralizing agents can be combined in a ratio that results in the target pH.

(8) Sodium sulfate or sodium bisulfate can optionally be added to the formulation to further increase tolerance to hard water. When combined with the fatty acid, sodium sulfate or sodium bisulfate increase the tolerance to hard water even more than the fatty acid or sulfate salts alone. When added, the sodium sulfate or sodium bisulfate is preferably present in the concentrated solution formulation at from about 0.1 to 10 wt %, more preferably about 2-8 wt %. While use of too much sodium sulfate or sodium bisulfate alone to provide hard water tolerance control can lead to solution gelling, the combination of a fatty acid with such relatively low levels of sodium sulfate or sodium bisulfate in the concentrate formulation further advantageously enables effective hard water tolerance control in a concentrate solution whit acceptable viscosity. Upon dilution to end-use concentrations, the diluted solution may preferably contain, e.g., 0.001-1 wt % sodium sulfate or sodium bisulfate, preferably, 0.01-0.5 wt %, and most preferably, 0.02-0.1 wt %.

(9) In further specific embodiments, the weight ratio of the one or more natural first organic acids sufficient to provide a solution pH of from about 1.2-5.0 to the sulfated fatty acid surfactant is preferably from about 1-4, as such ratios effectively enable providing sufficient acid to maintain the desired low pH in the diluted solution, and simultaneously sufficient surfactant to aid with cleaning ability of the diluted solution. Additionally, the weight ratio of the one or more natural first organic acids sufficient to provide a solution pH of from about 1.2-5.0 to the one or more fatty acids is preferably from 5-29, and more preferably from 9-28, as such ratios enable formulations that are relatively easy to formulate (formulations with lower ratios may be relatively difficult to formulate as concentrated solutions) and that provide effective hard water tolerance control (formulations with higher ratios may not provide as effective hard water control).

(10) Sanitizing and disinfecting solutions are prepared as highly concentrated solutions, which allow end users to prepare larger quantities of end-use solutions from small amounts of concentrated solution. This also facilitates shipping and handling by minimizing product volume. In a particular embodiment, e.g., the concentrated solution compositions of the invention are designed to be diluting with at least 9 additional parts of water to one part of the concentrate composition to form a diluted solution having a pH of horn about 1.5-5.0 used for cleaning, sanitizing, or disinfecting a food or non-food contact surface. In particular embodiments, it is preferred that the highly concentrated solution be prepared as a 30-1000× concentrate (i.e., formulated for dilution of 1 part of concentrated solution in 29 to 999 parts of water, respectively, to prepare the 1× end-use diluted formulation), preferably 40-300×, and most preferably 60-150×.

(11) The food or non-food contact surface may be treated with the 1× end-use diluted sanitizing or disinfecting solution by flooding, dipping, spraying, coating, wiping, or any other means that facilitates contact of the solution with the surface. The surface is exposed to the sanitizing or disinfecting solution for, e.g., from 10 seconds to 15 minutes, preferably 20 seconds to 10 minutes, and most preferably 30 seconds to 5 minutes. After exposure of the surface to the sanitizing or disinfecting solution, the surface may be allowed to dry. If a method such as flooding is used, excess solution is preferably removed (e.g., drained) prior to drying. When food contact surfaces are treated in this manner, they are sanitized or disinfected and the risk of transmission of pathogens is greatly reduced.

(12) The following are examples of several concentrated sanitizing and disinfecting formulations prepared according to this invention:

(13) Example 1: A 64× concentrate is prepared as outlined in the following Table 1.1:

(14) TABLE-US-00001 TABLE 1.1 WEIGHT PERCENT INGREDIENT 64× Concentrate 1× Dilution Citric acid 25.6 0.40 Lauric acid 1.3 0.02 Sodium lauryl sulfate 10.5 0.16 Sodium bicarbonate 2.6 0.04 Isopropanol 5.5 0.09 Water to 100% To 100%

(15) The pH of the resulting concentrated solution is approximately 2.20. The 64× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 64× concentrate with 63 parts of water. The pH of the resulting endorse solution is approximately 2.50.

(16) Example 2: A 64× concentrate is prepared as outlined in the following Table 1.2:

(17) TABLE-US-00002 TABLE 1.2 WEIGHT PERCENT INGREDIENT 64× Concentrate 1× Dilution Citric acid 25.6 0.40 Lauric acid 1.3 0.02 Sodium lauryl sulfate 10.5 0.16 Sodium bicarbonate 2.6 0.04 Isopropanol 5.5 0.09 Sodium sulfate 5.1 0.08 Water to 100% To 100%

(18) The pH of the resulting concentrated solution is approximately 2.21. The 64× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 64× concentrate with 63 parts of water. The pH of the resulting end-use solution is approximately 2.56.

(19) Example 3: A 64× concentrate is prepared as outlined in the following Table 1.3:

(20) TABLE-US-00003 TABLE 1.3 WEIGHT PERCENT INGREDIENT 64× Concentrate 1× Dilution Citric acid 25.6 0.40 Capric acid 1.3 0.02 Sodium lauryl sulfate 10.5 0.16 Sodium bicarbonate 2.6 0.04 Isopropanol 5.5 0.09 Water to 100% To 100%

(21) The pH of the resulting concentrated solution is approximately 2.18. The 64× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 64× concentrate with 63 parts of water. The pH of the resulting end-use solution is approximately 2.53.

(22) Example 4: A 64× concentrate is prepared as outlined in the following Table 1.4:

(23) TABLE-US-00004 TABLE 1.4 WEIGHT PERCENT INGREDIENT 64× Concentrate 1× Dilution Citric acid 25.6 0.40 Capric acid 1.3 0.02 Sodium lauryl sulfate 10.5 0.16 Sodium bicarbonate 4.8 0.08 Isopropanol 5.5 0.09 Sodium bisulfate 5.2 0.04 Water to 100% To 100%

(24) The pH of the resulting concentrated solution is approximately 1.97. The 64× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 64× concentrate with 63 parts of water. The pH of the resulting end-use solution is approximately 2.45.

(25) Example 5: A 128× concentrate is prepared as outlined in the following Table 1.5:

(26) TABLE-US-00005 TABLE 1.5 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Sodium bicarbonate 2.6 0.02 Isopropanol 5.5 0.04 Water to 100% To 100%

(27) The pH of the resulting concentrated solution is approximately 2.17. The 128× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 128× concentrate with 127 parts of water. The pH of the resulting end-use solution is approximately 2.66.

(28) Example 6: A 128× concentrate is prepared as outlined in the following Table 1.6:

(29) TABLE-US-00006 TABLE 1.6 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Sodium bicarbonate 2.6 0.02 Isopropanol 5.5 0.04 Sodium bisulfate 5.2 0.04 Water to 100% To 100%

(30) The pH of the resulting concentrated solution is 1.96. The 128× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 128× concentrate with 127 parts of water. The pH of the resulting end-use solution is approximately 2.58.

(31) Example 7: A 128× concentrate is prepared as outlined in the following Table 1.7:

(32) TABLE-US-00007 TABLE 1.7 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Sodium bicarbonate 2.9 0.02 Isopropanol 5.5 0.04 Water to 100% To 100%

(33) The pH of the resulting concentrated solution is approximately 2.49. The 128× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 128× concentrate with 127 parts of water. The pH of the resulting end-use solution is approximately 2.85.

(34) Example 8: A 128× concentrate is prepared as outlined in the following Table 1.8:

(35) TABLE-US-00008 TABLE 1.8 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Sodium bicarbonate 5.1 0.04 Isopropanol 5.5 0.04 Sodium bisulfate 5.2 0.04 Water to 100% To 100%

(36) The pH of the resulting concentrated solution is 2.21. The 128× concentrate is then diluted to prepare a 1× end-use diluted sanitizing/disinfecting solution by diluting 1 part of the 128× concentrate with 127 parts of water. The pH of the resulting end-use solution is approximately 2.61.

(37) Example 9: A concentrate that can be diluted either 1:64 or 1:128 is prepared as outlined in the following Table 1.9:

(38) TABLE-US-00009 TABLE 1.9 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Lauric acid 1.3 0.01 Sodium lauryl sulfate 10.5 0.08 Sodium citrate 1.8 0.01 Isopropanol 2.3 0.02 Water to 100% To 100%

(39) The pH of the resulting concentrated solution is 2.23. The concentrate is then diluted 1:64 or 1:128 to prepare the end-use diluted sanitizing/disinfecting solution by diluting 1 part of the concentrate with 63 or 127 parts of water, respectively. The pHs of the resulting end-use solutions are 2.32 and 2.41 for the 1:64 and 1:128 dilutions, respectively.

(40) Example 10: A concentrate that can be diluted either 1:64 or 1:128 is prepared as outlined in the following Table 1.10:

(41) TABLE-US-00010 TABLE 1.10 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Acetic acid 21.0 0.16 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Isopropanol 2.3 0.02 Water to 100% To 100%

(42) The pH of the resulting concentrated solution is 2.08. The concentrate is then diluted 1:64 or 1:128 to prepare the end-use diluted sanitizing/disinfecting solution by diluting 1 part of the concentrate with 63 or 127 parts of water, respectively. The pHs of the resulting end-use solutions are 2.58 and 2.63 for the 1:64 and 1:128 dilutions, respectively.

(43) Example 11: A concentrate that can be diluted either 1:64 or 1:128 is prepared as outlined in the following Table 1.11:

(44) TABLE-US-00011 TABLE 1.11 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Lauric acid 1.3 0.01 Sodium lauryl sulfate 10.5 0.08 Sodium citrate 1.8 0.01 Ethanol 5.5 0.04 Water to 100% To 100%

(45) The pH of the resulting concentrated solution is 2.32. The concentrate is then diluted 1:64 or 1:128 to prepare the end-use diluted sanitizing/disinfecting solution by diluting 1 part of the concentrate with 63 or 127 parts of water, respectively. The pHs of the resulting end-use solutions are 2.36 and 2.51 for the 1:64 and 1:128 dilutions, respectively.

(46) Example 12: A concentrate that can be diluted either 1:64 or 1:128 is prepared as outlined in the following Table 1.12:

(47) TABLE-US-00012 TABLE 1.12 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Acetic acid 21.0 0.16 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Ethanol 5.5 0.04 Water to 100% To 100%

(48) The pH of the resulting concentrated solution is 2.11. The concentrate is then diluted 1:64 or 1:128 to prepare the end-use diluted sanitizing/disinfecting solution by diluting 1 part of the concentrate with 63 or 127 parts of water, respectively. The pHs of the resulting end-use solutions are 2.68 and 2.69 for the 1:64 and 1:128 dilutions, respectively.

(49) Example 13: A concentrate that can be diluted either 1:64 or 1:12.8 is prepared as outlined in the following Table 1.13:

(50) TABLE-US-00013 TABLE 1.13 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Isopropanol 2.3 0.02 Water to 100% To 100%

(51) The pH of the resulting concentrated solution is 1.47. The concentrate is then diluted 1:64 or 1:128 to prepare the end-use diluted sanitizing/disinfecting solution by diluting 1 part of the concentrate with 63 or 127 parts of water, respectively. The pHs of the resulting end-use solutions are 2.23 and 2.30 for the 1:64 and 1:128 dilutions, respectively.

(52) Example 14: A concentrate that can be diluted either 1:64 or 1:128 is prepared as outlined in the following Table 1.14:

(53) TABLE-US-00014 TABLE 1.14 WEIGHT PERCENT INGREDIENT 128× Concentrate 1× Dilution Citric acid 25.6 0.20 Capric acid 2.6 0.02 Sodium lauryl sulfate 10.5 0.08 Ethanol 2.3 0.02 Water to 100% To 100%

(54) The pH of the resulting concentrated solution is 1.45. The concentrate is then diluted 1:64 or 1:128 to prepare the end-use diluted sanitizing/disinfecting solution by diluting 1 part of the concentrate with 63 or 127 parts of water, respectively. The pHs of the resulting end-use solutions are 2.25 and 2.36 for the 1:64 and 1:128 dilutions, respectively.

(55) Scenting of Formulations. Natural essential oils can be added to the sanitizing/disinfecting formulations to provide a natural, pleasing fragrance. Orange oil, lemon oil, and cinnamon oil were added to the formulations at up to 3 percent v/v. All three oils provided a pleasing scent to the concentrated and end-use diluted sanitizing/disinfecting formulations.

(56) Evaluation of Tolerance to Hard Water. The solutions prepared in Examples 1 to 8 were diluted to 1× using an appropriate volume of 375 or 500 ppm artificial hard water. The hard water was prepared shortly before use by combining die appropriate amount of calcium chloride (2.5 or 3.4 mM calcium ion for the 375 or 500 ppm hard water, respectively), magnesium chloride (1.3 or 1.7 mM magnesium ion for the 375 or 500 ppm hard water, respectively), and sodium bicarbonate (3.4 or 4.5 mM for the 375 or 500 ppm hard water, respectively) in distilled water. Each concentrated solution was then diluted in the 375 or 500 ppm hard water. Each solution was tested in triplicate. After dilution, the time to clouding and final appearance of the solutions after 24 hours were measured and the results are presented in Tables 1 and 2. Clouding of the solutions is a result of the interaction of sodium lauryl sulfate with the calcium (primarily) and magnesium ions in the hard water to create an insoluble precipitate that no longer has surfactant properties. In the case of the sanitizing and disinfecting formulations, formation of precipitates is undesired since it greatly reduces the cleaning and antibacterial properties of the solutions. Therefore, clouding is directly related to the ability of the sanitizing and disinfecting solutions to provide the desired efficacy (cleaning and antibacterial properties).

(57) Two control solutions without the fatty acid were used to compare the clouding results of the example formulations. The first control was 10.5% sodium lauryl sulfate in distilled water (Control Solution 1). The second control solution (Control Solution 2) was prepared as outlined in the following Table 2:

(58) TABLE-US-00015 TABLE 2 Control Solution 2 INGREDIENT WEIGHT % Citric acid 25.6 Sodium lauryl sulfate 10.5 Sodium bicarbonate 4.5 Isopropanol 5.5 Water to 100%

(59) The control solutions were diluted 1 part of concentrated solution its 63 (1:64 dilution) or 127 (1:128 dilution) parts of 375 or 500 ppm hard water. Clouding was defined as not being able to read 2.5 mm tall numbers on the opposite side of a clear polystyrene tube 28.5 mm in diameter containing the 1× diluted solution. Immediately after preparation, all solutions were clear. All example formulations prolonged the time until clouding when compared to the control solutions. Results are presented in the following Tables 3.1 and 3.2.

(60) TABLE-US-00016 TABLE 3.1 Time to clouding of sanitizing/disinfecting solutions diluted to 1× end-use concentrations in 375 ppm artificial hard water Time to Clouding (minutes) Appearance of Solution Test Solution (mean ± SD) at 24 Hours 64× Concentrate Diluted to 1× Example 1 15.7 ± 0.6 Completely opaque Example 2 40.0 ± 3.5 Completely opaque Example 3 39.3 ± 0.6 Completely opaque Example 4 211.7 ± 0.6  Can discern numbers but not legible Control Solution 1 (64×)  3.0 ± 0.0 Completely opaque Control Solution 2 (64×) 10.0 ± 0.0 Completely opaque 128× Concentrate Diluted to 1× Example 5 >1,440 Slightly hazy Example 6 >1,440 Slightly hazy Control Solution 1 (128×)  2.0 ± 0.0 Completely opaque Control Solution 2 (128×)  3.7 ± 1.2 Completely opaque

(61) TABLE-US-00017 TABLE 3.2 Time to clouding of sanitizing/disinfecting solutions diluted to 1× end-use concentrations in 500 ppm artificial hard water Time to Clouding (minutes) Appearance of Solution Test Solution (mean ± SD) at 24 Hours 64× Concentrate Diluted to 1× Example 1 10.3 ± 0.6 Completely opaque Example 2 21.3 ± 1.5 Completely opaque Example 3 20.7 ± 0.6 Completely opaque Example 4 55.3 ± 0.6 Can discern numbers but not legible Control Solution 1 (64×)  2.0 ± 0.0 Completely opaque Control Solution 2 (64×)  5.0 ± 1.0 Completely opaque 128× Concentrate Diluted to 1× Example 5 >1,440 Slightly hazy Example 6 >1,440 Slightly hazy Example 7 >1,440 Slightly hazy Example 8 >1,440 Slightly hazy Control Solution 1 (128×)  1.3 ± 0.6 Completely opaque Control Solution 2 (128×)  6.0 ± 0.0 Completely opaque

(62) Evaluation of Antimicrobial Effectiveness of 1× End-Use Diluted Solutions. The effectiveness of the sanitizing/disinfecting solutions from Examples 1 to 8 diluted to 1× end-use concentrations in 300 or 500 ppm artificial hard water was assessed in a suspension time kill assay against model gram positive (Staphylococcus aureus) and gram negative (Escherichia coli) bacteria. In brief, the bacterial suspension (˜1×1010 CFU/ml) was added to 9.9 times the volume of 1× end-use sanitizing/disinfecting solution prepared in 300 or 500 ppm artificial hard water. After 30 seconds, an aliquot of the test solution was removed and neutralized with culture broth. The neutralized solution containing bacteria was then plated on solid agar medium and allowed to incubate at 36±1° C. for 24-48 hours to identify viable colonies. Tables 4.1 and 4.2 summarize the results of duplicate replicates including the log-fold reduction in bacteria tor the two replicates combined for each solution and bacterium. All example formulations provided dramatic reductions in bacterial counts with a very short contact time (30 seconds).

(63) TABLE-US-00018 TABLE 4.1 Antibacterial efficacy of example sanitizing/disinfecting solutions diluted to 1× in 300 ppm hard water. CONCENTRATE INITIAL AVERAGE SANITIZING/ EXPOSURE BACTERIAL VIABLE LOG.sub.10 DISINFECTING TIME CONCNTRTN. COLONIES REDUCTION SOLUTION BACTERIUM REPLICATE (SECS) (CFU/ML) (CFU/ML) IN BACTERIA Example 1 Staphylococcus 1 30 6.65 × 10.sup.7 2.70 × 10.sup.4 3.67 (64×) aureus 2 1.58 × 10.sup.3 Eschericia coli 1 30 8.80 × 10.sup.7 No growth >7.25 2 No growth Example 2 Staphylococcus 1 30 6.65 × 10.sup.7 1.00 × 10.sup.1 >6.95 (64×) aureus 2 No growth Escherichia coli 1 30 8.80 × 10.sup.7 No growth >7.25 2 5.00 × 10.sup.0 Example 3 Staphylococcus 1 30 9.90 × 10.sup.6 No growth >6.30 (64×) aureus 2 No growth Example 4 Staphylococcus 1 30 9.90 × 10.sup.6 No growth >5.90 (64×) aureus 2 2.00 × 10.sup.1 Example 5 Staphylococcus 1 30 9.90 × 10.sup.6 No growth >6.30 (128×) aureus 2 No growth Example 6 Staphylococcus 1 30 9.90 × 10.sup.6 No growth >6.30 (128×) aureus 2 No growth Example 7 Staphylococcus 1 30 4.20 × 10.sup.8 No growth >6.92 (128×) aureus 2 No growth Escherichia coli 1 30 1.09 × 10.sup.9 No growth >7.34 2 No growth Example 8 Staphylococcus 1 30 4.20 × 10.sup.8 No growth >6.92 (128×) aureus 2 No growth Escherichia coli 1 30 1.09 × 10.sup.9 No growth >7.34 2 No growth

(64) TABLE-US-00019 TABLE 4.2 Antibacterial efficacy of example sanitizing/disinfecting solutions diluted to 1× in 500 ppm hard water. CONCENTRATE INITIAL AVERAGE SANITIZING/ EXPOSURE BACTERIAL VIABLE LOG.sub.10 DISINFECTING TIME CONCNTRTN COLONIES REDUCTION SOLUTION BACTERIUM REPLICATE (SECS) (CFU/ML) (CFU/ML) IN BACTERIA Example 7 Staphylococcus 1 30 4.20 × 10.sup.8 No growth >6.92 (128×) aureus 2 No growth Escherichia coli 1 30 1.09 × 10.sup.9 No growth >7.34 2 No growth Example 8 Staphylococcus 1 30 4.20 × 10.sup.8 No growth >6.92 (128×) aureus 2 No growth Escherichia coli 1 30 1.09 × 10.sup.9 No growth >7.34 2 No growth

(65) Evaluation of Corrosion of Concentrated and 1× End-Use Diluted Solutions. The corrosiveness of several of the concentrated and 1× end-use diluted solutions was tested by immersing pieces of stainless steel and aluminum in the concentrated or 1× end-use diluted solutions. The visual appearance of the metal pieces was assessed over time as summarized in Tables 5.1 and 5.2.

(66) TABLE-US-00020 TABLE 5.1 Appearance of stainless steel after constant immersion in concentrated or 1× end-use diluted solutions. Appearance Test Solution 1 Day 2 Days 4 Days 7 Days 14 Days 21 Days Example 1 64× Normal Normal Normal Normal Normal Normal concentrate 1× end-use Normal Normal Normal Normal Normal Normal dilution Example 5 128× Normal Normal Normal Normal Normal Normal concentrate 1× end-use Normal Normal Normal Normal Normal Normal dilution Example 6 128× Normal Normal Normal Normal Normal Normal concentrate 1× end-use Normal Normal Normal Normal Normal Normal dilution Positive Controls 10.5% Minimal Minimal Moderate Marked Marked Marked hypochlorite yellow yellow yellow yellow yellow yellow surface surface surface surface surface surface coating. coating. coating. coating. coating. coating. Moderate Moderate Moderate Moderate Moderate black black black black black corrosion. corrosion. corrosion. corrosion. corrosion. 0.246% Slight Slight Minimal Moderate Marked Marked hypochlorite yellow yellow yellow yellow yellow yellow surface surface surface surface surface surface coating. coating. coating. coating. coating. coating. Slight Slight Minimal Minimal black black black black corrosion. corrosion. corrosion. corrosion. 0.042% Normal Normal Slight Slight Slight Slight hypochlorite yellow yellow yellow yellow surface surface surface surface coating. coating. coating. coating. Negative Control Distilled Normal Normal Normal Normal Normal Normal Water Note: for severity of findings, slight < minimal < moderate < marked

(67) TABLE-US-00021 TABLE 5.2 Appearance of aluminum after constant immersion in concentrated or 1× end-use diluted solutions. Appearance Test Solution 1 Day 2 Days 4 Days 7 Days 14 Days 21 Days Example 1 64× Normal Normal Normal Normal Slight white Slight white concentrate film. film. 1× end-use Normal Normal Normal Normal Slight gray Slight gray dilution film. film. Example 5 128× Normal Normal Normal Normal Slight white Slight white concentrate film. film. 1× end-use Normal Normal Normal Normal Normal Slight gray dilution film. Example 6 128× Normal Normal Normal Normal Slight white Slight white concentrate film. film. 1× end-use Normal Normal Normal Normal Slight gray Slight gray dilution film. film. Positive Controls 10.5% Moderate Marked Marked Marked Marked Marked hypochlorite black and black and black and black and black and black and yellow yellow yellow white white white surface corrosion. corrosion. corrosion. corrosion. corrosion. coating and spots. 0.246% Moderate Moderate Marked Marked Marked Marked hypochlorite black black black black black black surface surface surface surface surface surface coating. coating. coating. coating. coating. coating. 0.042% Slight gray Minimal Marked Marked Marked Marked hypochlorite surface black black black black black coating. surface surface surface surface surface coating. coating. coating. coating. coating. Negative Control Distilled Normal Normal Normal Normal Normal Slight white Water film. Note: for severity of findings, slight < minimal < moderate < marked

(68) Stability of Concentrated Solutions During Elevated Temperature Storage. The stability of the concentrated solutions was tested by placing example solutions at 54° C. for 2 weeks and assessing when the solutions became cloudy or separated, both of which indicate instability of the solutions. The temperature and duration of the test was selected since the US Environmental Protection Agency recommends these parameters when assessing the stability of sanitizer/disinfectant formulations. Tables 6 and 7 demonstrate that isopropanol or ethanol increase the elevated temperature stability of the acid-anionic surfactant-fatty acid formulations. In addition, Table 8 demonstrates that the concentration of alcohol is critical since too low and stability is decreased.

(69) TABLE-US-00022 TABLE 6 Influence of isopropanol on the elevated temperature stability (54° C.) of acid-anionic surfactant-fatty acid formulations Aqueous Formulation Time to Cloud or Separate (Days) 25.6% citric acid 10  10.5% sodium lauryl sulfate 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 7% (v/v) isopropanol 25.6% citric acid 1 10.5% sodium lauryl sulfate 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 7% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid 6 10.5% sodium lauryl sulfate 1.4% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 7% (v/v) isopropanol 1.4% (v/v) decanoic acid

(70) TABLE-US-00023 TABLE 7 Influence of isopropanol or ethanol on the elevated temperature stability (54° C.) of acid-anionic surfactant-fatty acid formulations Aqueous Formulation Time to Cloud or Separate (Days) 25.6% citric acid 11  10.5% sodium lauryl sulfate 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 7% (v/v) ethanol 25.6% citric acid 2 10.5% sodium lauryl sulfate 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 7% (v/v) ethanol 2.8% (v/v) decanoic acid 25.6% citric acid 8 10.5% sodium lauryl sulfate 1.3% (w/v) lauric acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 7% (v/v) isopropanol 1.3% (w/v) lauric acid

(71) TABLE-US-00024 TABLE 8 Influence of varying isopropanol concentrations on the elevated temperature stability (54° C.) of acid-anionic surfactant-fatty acid formulations Aqueous Formulation Time to Cloud or Separate (Days) 25.6% citric acid 2 10.5% sodium lauryl sulfate 2.8% (v/v) decanoic acid 25.6% citric acid 1 10.5% sodium lauryl sulfate 0.1% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid 1 10.5% sodium lauryl sulfate 0.2% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid 4 10.5% sodium lauryl sulfate 1% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 2% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 3% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 4% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 5% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 6% (v/v) isopropanol 2.8% (v/v) decanoic acid 25.6% citric acid Stable and clear at 2 weeks 10.5% sodium lauryl sulfate 7% (v/v) isopropanol 2.8% (v/v) decanoic acid

(72) Evaluation of Foaming of 1× End-Use Diluted Solutions. The foaming of 1× end-use diluted solutions of Examples 1 to 8 was assessed by applying 15 ml of each 1× end-use diluted solution to a stainless steel countertop. A rectangular paper towel with the dimensions of 10.5 by 11 inches was used to wipe the solution in a circular motion in a clockwise followed by a counterclockwise direction on the countertop. Foaming was visually assessed along with the time to dissipation of foaming and residue remaining on the countertop. As positive controls, a solution of 10.5% sodium lauryl sulfate diluted in water to 0.164% (64× control) or 0.082% (128× control) were used. Results are presented in Table 9.

(73) TABLE-US-00025 TABLE 9 Test Time to Foam Residue Concen- Dissipation After Test Solution tration Foaming (seconds) Drying 64× Concentrate Diluted to 1× Example 1 1× Minimal 30 None (64× concentrate) Example 2 1× Minimal 22 None (64× concentrate) Example 3 1× Minimal 16 None (64× concentrate) Example 4 1× Minimal 44 None (64× concentrate) Positive 0.164% SLS Moderate 106 None Control (64×) 128× Concentrate Diluted to 1× Example 5 1× Slight 5 None (128× concentrate) Example 6 1× Slight 5 None (128× concentrate) Example 7 1× Slight 6 None (128× concentrate) Example 8 1× Slight 5 None (128× concentrate) Positive 0.082% SLS Minimal 52 None Control (128×) Note: foaming was assessed as slight < minimal < moderate < marked; SLS = sodium lauryl sulfate

(74) While the invention has been described in connection with several presently preferred embodiments thereof, those skilled in the art will appreciate that many modifications and changes may be made without departing from the true spirit and scope of the invention which accordingly is intended to be defined solely by the appended claims.