ZINC COMPOUNDS IN FOOD IMMERSION APPLICATIONS

Abstract

A method of treating a food product includes immersing the food product in a treatment solution, the treatment solution including a zinc compound. A treatment solution for immersion applications of food products includes a zinc compound. A system for treating a food product includes: a container configured to receive the food product; and a treatment solution contained within the container. The container and treatment solution are capable of immersing the food product and the treatment solution includes a zinc compound.

Claims

1. A method of treating a food product, comprising: immersing the food product in a treatment solution; wherein the treatment solution comprises a zinc compound.

2. The method of claim 1, wherein the food product comprises poultry and the treatment solution comprises 30-1000 ppm of zinc.

3. The method of claim 1, wherein the food product comprises beef or pork and the treatment solution comprises 200-400 ppm of zinc.

4. The method of claim 1, wherein the food product comprises a fruit or vegetable and the treatment solution comprises 20-100 ppm of zinc.

5. The method of claim 1, wherein the treatment solution further comprises an acid selected from sulfuric acid, acetic acid, phosphoric acid, citric acid, hydrochloric acid, lactic acid, and/or malic acid.

6. The method of claim 5, wherein the acid is sulfuric acid.

7. The method of claim 6, wherein a weight ratio of the sulfuric acid to zinc in the treatment solution is from 1:30 to 1:1.

8. The method of claim 5, wherein the treatment solution comprises 300-700 ppm of zinc.

9. The method of claim 8, wherein the pH of the treatment solution is less than 3.

10. The method of claim 1, wherein the zinc compound comprises zinc chloride, zinc bromide, zinc sulfate, zinc acetate, zinc nitrate, zinc oxide nanoparticles, zinc performate, zinc peracetate, or combinations thereof.

11. A treatment solution for immersion applications of food products, the treatment solution comprising: a zinc compound in an amount such that the treatment solution comprises 20-3000 ppm of zinc.

12. The treatment solution of claim 11, further comprising an acid selected from sulfuric acid, acetic acid, phosphoric acid, citric acid, hydrochloric acid, lactic acid, and/or malic acid.

13. The treatment solution of claim 12, wherein the acid is sulfuric acid.

14. The treatment solution of claim 11, wherein a pH of the treatment solution is less than 3.

15. The treatment solution of claim 11, wherein the zinc compound comprises zinc chloride, zinc bromide, zinc sulfate, zinc acetate, zinc nitrate, zinc oxide nanoparticles, zinc performate, zinc peracetate, or combinations thereof.

16. A system for treating a food product, the system comprising: a container configured to receive the food product; and a treatment solution contained within the container; wherein the container and treatment solution are capable of immersing the food product; and wherein the treatment solution comprises a zinc compound.

17. The system of claim 16, wherein the treatment solution further comprises an acid selected from sulfuric acid, acetic acid, phosphoric acid, citric acid, hydrochloric acid, lactic acid, and/or malic acid.

18. The system of claim 17, wherein the acid is sulfuric acid.

19. The system of claim 18, wherein a weight ratio of the sulfuric acid to zinc in the treatment solution is from 1:30 to 1:1.

20. The system of claim 16, wherein the zinc compound comprises zinc chloride, zinc bromide, zinc sulfate, zinc acetate, zinc nitrate, zinc oxide nanoparticles, zinc performate, zinc peracetate, or combinations thereof.

Description

EXAMPLES

Example 1

[0021] Drums (poultry) were purchased from a local retailer, frozen, and thawed for testing. The parts were stored at refrigeration temperatures until time of testing. As a control, five drums (Sample IDs 1-5) were individually, aseptically rinsed (as referenced herein, rinsing is per FSIS Directive 10,250.1; in Example 1, 40 ml of rinsate was used). These drums represent what was microbiologically present on the drums before treatment.

[0022] Next, a solution of 1% zinc sulfate/sulfuric acid (concentrations described herein are based on zinc content) was slowly added and manually agitated into 1 gallon of water. A total of 233 mL of the 1% solution was added to yield a solution with a final pH of 2.96. Five drums (Sample IDs 6-10) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0023] Next, 1 gallon of water and 1,893 mL of a 50 ppm zinc sulfate/sulfuric acid solution were combined in a bucket to yield a 25 ppm zinc sulfate/sulfuric acid solution. Five drums (Sample IDs 11-15) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0024] Finally, 2 gallons of water and 757 mL of a 500 ppm zinc sulfate/sulfuric acid solution were combined in a bucket to yield a 50 ppm zinc sulfate/sulfuric acid solution. Five drums (Sample ID's 16-20) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0025] All rinsate samples collected were placed in a refrigerator overnight. The samples were analyzed for 3M Aerobic Plate Count (APC) Petrifilm™ (AOAC Official Method 990.12), and Enterobacteriaceae (EB) Petrifilm™ (AOAC Official Method 2003.01). The samples were recorded as counts, which were then converted to log.sub.10 CFU/mL for statistical analysis of the means. The results are summarized in Table 1 below.

TABLE-US-00001 TABLE 1 Aerobic plate count Enterobacteriaceae Treatment Solution (log.sub.10 CFU/ml) (log.sub.10 CFU/ml) Sample IDs 1-5 (control) 8.5 7.1 Sample IDs 6-10 (1% zinc 8.0 7.3 sulfate/sulfuric acid) Reduction from 0.5 + 0.2 control P-Value* 0.0001 0.0473 Sample IDs 11-15 (25 ppm 7.8 7.1 zinc sulfate/sulfuric acid) Reduction from 0.7 0.0 control P-Value* 0.0001 0.8358 Sample IDs 16-20 (50 ppm 7.7 6.8 zinc sulfate/sulfuric acid) Reduction from 0.8 0.3 control P-Value* 0.0001 0.2413 *Using a 95% confidence interval where a = 0.05, a P-Value < a indicates statistical significance.

[0026] Table 1 above shows statistically significant microbial reduction in APC for all zinc sulfate/sulfuric acid treatment groups when used on poultry parts in a dip application when compared to the control group.

[0027] EB analysis showed a statistically significant microbial growth with the 1% zinc sulfate/sulfuric acid. The 25 ppm zinc sulfate/sulfuric acid treatment group showed no microbial reduction or growth from a control group while 50 ppm zinc sulfate/sulfuric acid treatment group shows slight microbial reduction, but not a statistically significant reduction. This Example suggests that a higher concentration of zinc sulfate leads to higher microbial reduction on poultry parts in a dip application. However, wastewater regulations are the limiting factor in determining maximum concentrations of zinc allowed in treatments.

Example 2

[0028] Drums (poultry) were purchased from a local retailer, frozen, and thawed for testing. The parts were stored at refrigeration temperatures for 72 hours, then allowed to sit at room temperature for 24 hours prior to testing. As a control, five drums (Sample IDs 1-5) were individually, aseptically rinsed (100 ml of rinsate).

[0029] Next, approximately 82 mL of a 3,000 ppm zinc sulfate/sulfuric acid solution was added and manually agitated in 1 gallon of tap water in a 3-gallon bucket to yield a 50 ppm zinc sulfate/sulfuric acid solution. The pH was recorded as 1.2. Five drums (Sample IDs 6-10) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0030] Next, 1 gallon of water and 630 mL of a 3,000 ppm zinc sulfate/sulfuric acid solution were added to a bucket to yield a 500 ppm zinc sulfate/sulfuric acid solution. Five drums (Sample IDs 11-15) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0031] Next, 1 gallon of water and 1,262 mL of a 3,000 ppm zinc sulfate/sulfuric acid solution were added to a bucket to yield a 1,000 ppm zinc sulfate/sulfuric acid solution. Five drums (Sample IDs 16-20) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0032] Lastly, 1 gallon of water and 1,893 mL of a 3,000 ppm zinc sulfate/sulfuric acid solution were added to a bucket to yield a 1,500 ppm zinc sulfate/sulfuric acid solution. Five drums (Sample IDs 21-25) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0033] All rinsate samples collected were placed in a refrigerator overnight. The samples were analyzed for 3M Aerobic Plate Count (APC) Petrifilm™ (AOAC Official Method 990.12) and Enterobacteriaceae (EB) Petrifilm™ (AOAC Official Method 2003.01). The samples were recorded as counts, which were then converted to log.sub.10 CFU/mL for statistical analysis of the means. The results are summarized in Table 2 below.

TABLE-US-00002 TABLE 2 Aerobic plate count Enterobacteriaceae Treatment Solution (log.sub.10 CFU/ml) (log.sub.10 CFU/ml) Sample IDs 1-5 (control) 5.1 2.2 Sample IDs 6-10 (50 ppm zinc 4.3 1.7 sulfate/sulfuric acid) Reduction from control 0.8 0.5 P-Value* 0.0883 0.1256 Sample IDs 11-15 (500 ppm zinc 4.4 1.2 sulfate/sulfuric acid) Reduction from control 0.7 1.0 P-Value* 0.0096 0.0099 Sample IDs 16-20 (1000 ppm 4.1 1.4 zinc sulfate/sulfuric acid) Reduction from control 1.0 0.8 P-Value* 0.0111 0.2056 Sample IDS 21-25 (1500 ppm 3.6 1.0 zinc sulfate/sulfuric acid) Reduction from control 1.5 1.2 P-Value* 0.0001 0.0044 *Using a 95% confidence interval where a = 0.05, a P-Value < a indicates statistical significance.

[0034] Table 2 above shows statistically significant microbial reduction in APC for all zinc sulfate/sulfuric acid treatment groups—except for the 50 ppm zinc sulfate/sulfuric acid solution—when used on poultry parts in a dip application when compared to the control group.

[0035] EB analysis showed a statistically significant microbial reduction with the 500 ppm and 1500 ppm zinc sulfate/sulfuric acid solutions. As with Example 1, this Example suggests that a higher concentration of zinc sulfate leads to higher microbial reduction on poultry parts in a dip application. However, wastewater regulations are the limiting factor in determining maximum concentrations of zinc allowed in treatments.

Example 3

[0036] Drums (poultry) were purchased from a local retailer, frozen, and thawed for testing. The parts were allowed to sit at room temperature for 24 hours prior to testing. As a control, five drums (Sample IDs 1-5) were individually, aseptically rinsed (100 ml of rinsate).

[0037] Next, approximately 630 mL of 3,000 ppm zinc sulfate was added and manually agitated in 1 gallon of tap water in a 3-gallon bucket to yield a 500 ppm zinc sulfate solution. Five drums (Sample IDs 6-10) were fully submerged in the zinc sulfate solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0038] Next, 1 gallon of water and 4 ml of sulfuric acid were added to a bucket to yield a solution having a pH of 1.2. Five drums (Sample IDs 11-15) were fully submerged in the sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0039] Lastly, 1 gallon of water and 630 mL of 3,000 ppm zinc sulfate/sulfuric acid solution were added to a bucket to yield a 500 ppm zinc sulfate/sulfuric acid solution having a pH of 1.2. Five drums (Sample IDs 16-20) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0040] All rinsate samples collected were placed in a refrigerator overnight. The samples were analyzed for 3M Aerobic Plate Count (APC) Petrifilm™ (AOAC Official Method 990.12), E. coli/Coliform (EC/CO) Petrifilm™ (AOAC Official Method 998.08), and Enterobacteriaceae (EB) Petrifilm™ (AOAC Official Method 2003.01). The samples were recorded as counts, which were then converted to log.sub.10 CFU/mL for statistical analysis of the means. The results are summarized in Table 3 below.

TABLE-US-00003 TABLE 3 Aerobic plate count Enterobacteriaceae Treatment Solution (log.sub.10 CFU/ml) (log.sub.10 CFU/ml) Sample IDs 1-5 (control) 5.2 2.8 Sample IDs 6-10 (500 ppm 4.5 1.7 zinc sulfate) Reduction from 0.7 1.1 control P-Value* 0.2109 0.1120 Sample IDs 11-15 (1.2 pH 4.6 1.7 sulfuric acid) Reduction from 0.6 1.1 control P-Value* 0.2652 0.1493 Sample IDs 16-20 (500 ppm 4.4 1.0 zinc sulfate/sulfuric acid) Reduction from 0.8 1.8 control P-Value* 0.2451 0.0392 *Using a 95% confidence interval where a = 0.05, a P-Value < a indicates statistical significance.

[0041] Table 3 above shows statistically significant microbial reduction in EB analysis for the 500 ppm zinc sulfate/sulfuric acid treatment groups. This Example suggests that zinc sulfate does individually exhibit some antimicrobial properties. These properties are shown to be improved when the zinc sulfate is combined with sulfuric acid.

Example 4

[0042] Drums (poultry) were purchased from a local retailer, frozen, and thawed for testing. The parts were allowed to sit at room temperature for 24 hours prior to testing. As a control, five drums (Sample IDs 1-5) were individually, aseptically rinsed (100 ml of rinsate).

[0043] Next, approximately 630 mL of 3,000 ppm zinc sulfate was added and manually agitated in 1 gallon of tap water in a 3-gallon bucket to yield a 500 ppm zinc sulfate solution. Five drums (Sample IDs 6-10) were fully submerged in the zinc sulfate solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0044] Next, sulfuric acid was added and manually agitated in 1 gallon of tap water in a bucket to yield a solution having a pH of 1.2. Five drums (Sample IDs 11-15) were fully submerged in the sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0045] Lastly, 1 gallon of water and 630 mL of 3,000 ppm zinc sulfate/sulfuric acid solution were added to a bucket to yield a 500 ppm zinc sulfate/sulfuric acid solution having a pH of 1.2. Two sets of five drums (Sample IDs 16-20 and 21-25) were fully submerged in the zinc sulfate/sulfuric acid solution, manually agitated for 10 seconds, then removed and allowed to drip for 60 seconds. The drums were individually, aseptically rinsed.

[0046] All rinsate samples collected were placed in a refrigerator overnight. The samples were analyzed for 3M Aerobic Plate Count (APC) Petrifilm™ (AOAC Official Method 990.12), and Enterobacteriaceae (EB) Petrifilm™ (AOAC Official Method 2003.01). The samples were recorded as counts, which were then converted to log.sub.10 CFU/mL for statistical analysis of the means. The results are summarized in Table 4 below.

TABLE-US-00004 TABLE 4 Aerobic plate count Enterobacteriaceae Treatment Solution (log.sub.10 CFU/ml) (log.sub.10 CFU/ml) Sample IDs 1-5 (control) 7.9 4.9 Sample IDs 6-10 (500 ppm 7.2 3.3 zinc sulfate) Reduction from 0.7 1.9 control P-Value* 0.0215 0.0009 Sample IDs 11-15 (1.2 pH 7.2 4.4 sulfuric acid) Reduction from 0.7 0.5 control P-Value* 0.0082 0.0476 Sample IDs 16-20 (500 ppm 6.6 3.2 zinc sulfate/sulfuric acid) Reduction from 1.3 1.7 control P-Value* 0.0009 0.0122 Sample IDs 21-25 (500 ppm 6.5 3.2 zinc sulfate/sulfuric acid) Reduction from 1.4 1.7 control P-Value* 0.0001 0.0008 *Using a 95% confidence interval where a = 0.05, a P-Value < a indicates statistical significance.

[0047] Table 4 above shows statistically significant microbial reduction in APC and EB analysis for the 500 ppm zinc sulfate only samples (6-10). Additionally, sulfuric acid treatment with a solution having a pH of 1.2 or less provided statistically significant reductions in APC and EB analysis. However, the combination of sulfuric acid and zinc sulfate in samples 16-25 showed greater reduction in APC analysis than either of the individual treatments.

[0048] Zinc sulfate has natural antimicrobial properties that are shown herein to effectively reduce microbial loads on poultry parts. When combined with sulfuric acid, the pH adjustment adds an additional mode of defense against bacteria. As shown herein, a zinc sulfate/sulfuric acid solution provides a synergistic antimicrobial that increase antimicrobial efficacy when compared to solutions of the individual components.

[0049] The above specific example embodiments are not intended to limit the scope of the claims. The example embodiments may be modified by including, excluding, or combining one or more features or functions described in the disclosure. The description of the present disclosure has been presented for purposes of illustration and description but is not intended to be exhaustive or limited to the embodiments in the form disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the disclosure. The illustrative embodiments described herein are provided to explain the principles of the disclosure and the practical application thereof, and to enable others of ordinary skill in the art to understand that the disclosed embodiments may be modified as desired for a particular implementation or use. The scope of the claims is intended to broadly cover the disclosed embodiments and any such modification.