EVALUATING THE EFFICACY OF NOVEL SANITIZERS IN EGG WASHING

• Sponsoring Institution: National Institute of Food and Agriculture
• Project Status: TERMINATED
• Funding Source: HATCH
• Reporting Frequency: Annual
• Accession No.: 1011583
• Project No.: NJ10106
• Project Start Date: Nov 18, 2016
• Project End Date: Oct 31, 2019

Project Director
Karwe, MU, V.

Recipient Organization
RUTGERS, THE STATE UNIVERSITY OF NEW JERSEY
3 RUTGERS PLZA
NEW BRUNSWICK,NJ 08901-8559

Performing Department
Food Science

Non Technical Summary
FDA regulations require shell egg producers to implement measures to prevent Salmonella contamination of eggs. Current decontamination strategies may:a) leave undesirable chemical residuesb) cause degradation of the cuticlec) increase bacterial resistanced) have adverse environmental impacts, ande) be of limited effectiveness.Novel methods are needed to effectively eliminate pathogens and significantly reduce the microbial load on eggs with less detrimental effects on the quality of eggs and the environment. Our objective is to apply Plasma Activated Water (PAW) and plasma treated Acidified Electrolyzed Water (P- AEW) as novel and safe sanitizers during egg washing to inactivate Enterobacter aerogenes which is a non pathogenic surrogate for Salmonella Enteritidis. Efficacy of the novel sanitizers will be compared with conventional methods (chlorine and quaternary ammonium sanitizers). PAW and P- AEW will be generated using existing equipment at Rutgers University. The effects of all sanitizers on the structural integrity of washed eggs will be assessed based on the changes in surface color, porosity, microstructure, and mechanical properties of egg shells. Treatment temperature and time will be optimized for each novel sanitizer based on microbial inactivation efficacy and shell integrity. The identification of novel treatments for egg washing will provide egg producers with an attractive alternative strategy for control of Salmonella with minimal loss in quality.

Animal Health Component

0%

Research Effort Categories

Basic

33%

Applied

33%

Developmental

34%

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
501	3299	2020	100%

Knowledge Area
501 - New and Improved Food Processing Technologies;

Subject Of Investigation
3299 - Poultry, general/other;

Field Of Science
2020 - Engineering;

Keywords

plasma activated water

egg quality

salmonella enteritidis

acidified electrolyzed water

Goals / Objectives
The overall aim of the project is to use PAW and plasma treated AEW as novel and safe sanitizers for egg washing to inactivate Enterobacter aerogenes with minimal egg quality loss.The specific objectives are:To assess the efficacy of PAW and plasma treated AEW as sanitizers on the inactivation of Enterobacter aerogenes during egg washing and compare them to conventional methods (chlorine and quaternary ammonium sanitizers).To gain insights into the effects of novel sanitizers on the structural integrity of washed eggs by using mechanical and optical techniques.

Project Methods
The overall experimental design includes inoculating eggs, washing egg with novel treatments and evaluating the effectiveness of the treatment based on quality parameters and microbial inactivation. Enterobacter aerogenes, a surrogate microorganism for Salmonella with similar attachment characteristics, will be used in this study.Fresh unwashed eggs (< 2 days old) will be procured from an Extension Research Poultry Farm of the Department of Animal Sciences at Rutgers University. Defect free egg samples will be chosen from each batchand a random sample will betested for the presence of native Enterobacter aerogenes, Salmonella Enteritidis and to measure aerobic plate count. The batch of eggs showing presence of these microorganisms will be discarded. A design of experiments will be used to conduct eggs washing experiments with varying time and temperature for each sanitizing treatment (PAW and plasma treated AEW). For bacterial enumeration, eggs that have been inoculated and treated using the novel and conventional sanitizers will be rinsed with buffered peptone water in sterile plastic bags. The buffered solution will be serially diluted and plated on tryptic soy agar with nalidixic acid for Enterobacter aerogenes enumeration (Bialka et al., 2004). The effect of the sanitizing treatments on the egg shell quality will be assessed in terms of color, porosity, structural integrity and mechanical properties.Statistical analysis will be performed to correlate the microbial inactivation responses, e.g., log reduction (CFU/egg) to washing time and temperature for each novel sanitizer using the statistical software SAS. The results will be compared with those obtained using conventional chemical sanitation methods using appropriate statistical criteria.

Progress 11/18/16 to 10/31/19

Outputs
Target Audience:General public, food processors, regulatory agencies. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One post-doctoral associate worked on this project. How have the results been disseminated to communities of interest?Through peer reviewed publications and completion of a post-doctoral thesis What do you plan to do during the next reporting period to accomplish the goals? Nothing Reported

Impacts
What was accomplished under these goals? The efficacy of plasma activated water onmicrobial inactivation of Enterobacter aerogenes, a non-pathogenic surrogate of the Salmonella family, was determined. This was done by spot inoculating farm fresh eggs, and washing them with plasma activated water as well as a commercial sanitizer,followed by enumerating the reduction ofbacteria population on egg shells. We also assessed theeffect of plasma activated water and a commerical sanitizeron egg shell integrity and quality, usingtexture analysis and color measurements.

Publications

• Type: Journal Articles Status: Submitted Year Published: 2020 Citation: Shruthi L. Narasimhan, Deepti Salvi, Juzhong Tan, Donald W. Schaffner, Mukund V. Karwe,"Suitability of Cold Plasma-Activated Water as a Sanitizer for Washing Eggs" to be submitted to Food Research International, 2020.

Progress 10/01/17 to 09/30/18

Outputs
Target Audience:General public, food processors, regulatory agencies. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One graduate student and one undergraduate intern were trained. How have the results been disseminated to communities of interest?Results were presented in a M.S. Thesis defenseand at a multistate project (NC1023) annual meeting. What do you plan to do during the next reporting period to accomplish the goals?Most of the goals have been accomplished. We are now working on writing a manucript for publication in a refereed journal. We will also consider writing a proposal to a funding agency on this topic, if an appropriate oppotunity arises.

Impacts
What was accomplished under these goals? We tested the inactivation efficacy of plasma activated water (PAW) on E. aerogenes (non-pathogenic surrogate of Salmonella sp.) as well as its impact of egg shell cuticle and shell strength. Preliminary planktonic-cell experiments showed that washing with distilled water (DW) can reduce E. aerogenes concentration by 0.17±0.12 log CFU/ml from initial concentration of 9.21±0.06 log CFU/ml. Whereas PAW or Quat. Ammonia (QA) could reduce bacterial concentration by 6 log CFU/ml. Washing egg shell by PAW and QA with massaging reduced the E. aerogenes concentration on egg shells from 7.91±0.33 log CFU/egg to less than 2.30 log CFU/egg and in wash water from 3.64 ± 0.69 log to less than 0.69 log CFU/ml. Washing eggs by PAW and DW did not significantly change the cracking force of shell eggs, in any orientation, i.e., vertical and horizontal. Washing eggs with QA made egg shells easier to crack and changed the color of egg shells by damaging egg cuticles.

Publications

• Type: Theses/Dissertations Status: Published Year Published: 2018 Citation: Lakshmi Narasimhan, Shruthi. Efficacy and suitability of cold plasma generated novel sanitizer in egg washing

Progress 11/18/16 to 09/30/17

Outputs
Target Audience:General Public, Food Processors, and Regulatory Agencies. Changes/Problems: Nothing Reported What opportunities for training and professional development has the project provided?One graduate student and one undergraduate intern are being trained. How have the results been disseminated to communities of interest?Results were presented at local and national scientific conferences. What do you plan to do during the next reporting period to accomplish the goals?a) Determination of the efficacy of microbial inactivation of Enterobacter aerogenes, a non-pathogenic surrogate of the Salmonella family. This will be done by spot inoculating farm fresh eggs, and washing them with novel sanitizers, and enumerating the reduction in bacteria on egg shell. b) Assessment of effect of PAW and plasma treated AEW on egg shell integrity and quality, to be determined by texture analysis and SEM techniques.

Impacts
What was accomplished under these goals? Farm fresh eggs with intact cuticle were stained with Cuticle Blu die (MS Technologies), both before and after treatment with novel sanitizers. Cuticle Blu die works with the principle of attachment of colored pigment to protein present in the cuticle. The intensity of green color on the egg determines the integrity of cuticle. This was measured using a Konica Minolta CR-410 colorimeter, in L*, a*, b* scale. The values thus obtained were compared to those of industrially washed and stained eggs, and eggs washed in industrially used sanitizer (Quat ammonia). Comparison was made on the basis of the changes in the E-value (ΔE), which is an absolute value that accommodates changes in L*, a* and b* values. It was found by visual inspection that eggs washed in Plasma Activated Water (PAW) and plasma treated Acidified Electrolyzed Water (AEW) had similar color profiles, while eggs washed in Quat ammonia and market bought eggs had a very light green tinge. This indicates that the cuticle strength of market bought eggs is very weak. On the other hand, eggs washed in PAW and plasma treated AEW had preserved the integrity of the cuticle. Evaluation of the ΔE values revealed similar results, wherein PAW and plasma treated AEW washed eggs had values almost the same as that of unsanitized farm fresh eggs. This study supports the hypothesisthat the novel sanitizers used do not cause significant detrimental effects to cuticle coverage on shell eggs.

Publications

• Type: Conference Papers and Presentations Status: Other Year Published: 2017 Citation: Shruthi L. N., Salvi D., Schaffner D.W., and Karwe M.V. (2017) Efficacy of Cold Plasma Generated Novel Sanitizers in Egg Washing, International Association for Food Protection Annual Meeting 2017, July 9-12 in Tampa, Florida.