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Egg waste is a major contributor to global food waste, accounting for 15% of discarded food in the United States. Typically, eggs have a shorter shelf life at room temperature and are preserved in refrigeration from production to consumption. However, maintaining constant refrigeration is energy‐intensive and expensive. Here, a bionanocomposite coating has been developed that incorporates each element of eggs – egg white, yolk, and eggshell – to increase the shelf life of fresh eggs without requiring further refrigeration. The quality of eggs has been successfully preserved for up to three weeks at room temperature. The coated eggs maintain the highest grade (AA) and exhibit improved Haugh Unit (HU), Yolk Index (YI), and pH compared to uncoated eggs. The coating reduces weight loss by ≈37% with an increase in HU (≈12.5%) and YI (≈13.9%). Morphological analysis reveals strong adhesion of the coating to the eggshell surface, showcasing promising barrier properties. The coating demonstrates an optimal combination of oxygen permeability (≈12.2 cm3 µm m−2 d−1 kPa−1) and water vapor transmission (≈31.5 g mm m−2 per day) with excellent antimicrobial properties. Overall, this approach of repurposing eggs into a high‐performance coating shows a promising viable alternative to refrigeration and a solution to combat egg waste. [ABSTRACT FROM AUTHOR]

Eggs in the United States are typically washed using chemical sanitizers such as quaternary ammonia (QA) or chlorine. Such treatments generate wash water, which could be potentially hazardous to the environment. A novel, nonthermal sanitization technique for washing shell eggs using cold plasma-activated water (PAW) was investigated in this study. The inactivation efficacy of PAW on Klebsiella michiganensis and the impact of PAW on the cuticle of the eggshell and shell strength were tested in comparison to QA. Washing inoculated eggs with PAW and QA achieved a similar microbial reduction (>5.28 log CFU/egg). Colorimetric analysis showed that ∆ E -value for PAW-treated eggs was significantly lower than QA-treated eggs, suggesting higher cuticle coverage in eggs treated with PAW. The texture analysis to test for shell egg strength indicated that washing eggs with PAW did not affect the structural integrity of the eggshell when compared to eggs washed with QA. According to this study, PAW has the potential as an alternative to commercial sanitizers like QA in the egg-washing industry. PAW does not detrimentally impact shell strength or cuticle coverage and provides similar microbial reduction efficacy. [ABSTRACT FROM AUTHOR]

Eggshell color can greatly influence visual appeal of table eggs, and within the United States, table eggs are normally sorted and marked according to eggshell color to maximize consumer appeal. Recently, table egg producers have noted increased incidence of "off-color" or tinted (TT) eggs derived from white egg laying breeder hens. Therefore, the objectives of this study were to determine the production characteristics and resultant eggshell color of laying hens hatched from different colored eggs. Hy-Line W36 eggs were obtained from a commercial breeder operation and egg-shell color was assessed with a colorimeter to separate eggs into groups of tinted (TT) and nontinted (NT) eggs before incubation. Treatment groups were placed into separate hatching trays. At hatching, chicks from each treatment group were individually wing-banded. Pullets were randomly allocated into cages according to treatment groups at 18 wk. Birds were placed into individual cages, with 5 consecutive cages representing a treatment replicate. Each treatment was replicated 24 times for a total of 120 birds per treatment and fed a nutritionally complete layer diet. Production performance was evaluated from 18 to 34 wk of age. Average weekly egg production was calculated. Feed intake, egg weights, egg mass, feed conversion ratio, and egg color were analyzed every 2 wk. Birds were weighed every 4 wk until completion of the study. Birds hatched from TT eggs had significantly increased BW through-out the experimental period. Hen-day egg production was significantly different when compared with the NT treatment at 19 and 20 wk of age. Eggshell color was also found to be significantly different for the NT and TT groups with TT eggs being significantly further from true white. Selection of progeny based on eggshell color may be a criterion for selecting white egg layers as layers hatched from TT eggs resulted in more off-color eggs, which may affect consumer acceptance for buying white table eggs. [ABSTRACT FROM AUTHOR]

In Australia, Europe and the United States, eggs and egg products are frequently associated with Salmonella food poisoning outbreaks. Many of the egg-associated Salmonella outbreaks have been due to the products such as mayonnaise, ice-cream and cold desserts which are eaten without cooking following the addition of raw egg. The ability of four Salmonella isolates (one each of S. Singapore, S. Adelaide, S. Worthington and S. Livingstone) to penetrate washed and unwashed eggs using whole egg and agar egg penetration methods was investigated in the current study. The results of the agar penetration experiment indicated that all the isolates used in the present study have the capacity to penetrate the eggshell. Eggshell penetration by the S. Worthington isolate was higher but not significant (p=0.06) in washed eggs compared to unwashed eggs. However, for all other isolates (S. Singapore, S. Adelaide and S. Livingstone), there was no significant difference in penetration of washed and unwashed eggs. Statistical analysis indicated that cuticle score was a significant linear predictor of Salmonella eggshell penetration. Whole egg penetration results showed that all of the Salmonella isolates used in the present study were capable of surviving on the eggshell surface after 21days of incubation (at 20°C) following a high dose of inoculation (105 CFU/mL). The combined data of all isolates demonstrated that, the survival rate of Salmonella on eggshells (inoculated with 105 CFU/mL) was significantly higher (p=0.002) at 20°C as compared to 37°C. S. Singapore, S. Worthington, and S. Livingstone were not detected in egg internal contents whereas S. Adelaide was detected in one egg's internal contents. [ABSTRACT FROM AUTHOR]

Shell eggs contaminated with Salmonella Enteritidis pose serious food safety and public health concerns. More vigilant product testing calls for rapid, accurate, and reliable detection methods for Salmonella. Two loop-mediated isothermal amplification (LAMP) assays targeting different regions of the Salmonella invasion protein (encoded by invA) have been reported. In this study, performance of the two LAMP assays was compared with that of PCR in detecting Salmonella Enteritidis and Salmonella Typhimurium strains in experimentally contaminated egg homogenates. Both LAMP assays were highly specific. The detection limits were approximately 1 CFU per reaction for both Salmonella serovars in pure culture, 100-fold more sensitive than that of PCR. Standard curves generated suggested a good linear relationship between Salmonella cell numbers and LAMP turbidity signals. In spiked egg homogenate, the LAMP assays could detect both Salmonella serovars down to 104 CFU/25 ml without enrichment and 100 CFU/25 ml with 8-h enrichment. In contrast, PCR was unable to detect either Salmonella serovar in egg homogenates spiked with less than 106 CFU/25 ml by direct testing and required at least 12 h of enrichment for samples spiked with 10¹ CFU/25 ml and 24 h for those with 100 CFU/25 ml. The complete LAMP assay took about 10 h (including 8 h of enrichment) to complete. In conclusion, the two LAMP assays were rapid, accurate, and reliable methods for detecting Salmonella serovars in shell eggs and may be adopted in routine egg testing for Salmonella to improve egg safety and protect public health. [ABSTRACT FROM AUTHOR]

To examine regional variation in strontium (Sr), which at high concentrations may reduce eggshell quality, increase egg breakage and reproductive failure, we analyzed Sr, and calcium (Ca) concentrations and Sr/Ca ratios in eggshells from 20 avian species from California, Texas, Idaho, Kansas, and Michigan. In addition, we included data previously reported from Arizona to expand the regional comparisons and to better establish patterns of Sr, and Sr/Ca ratios in bird species across the United States. We found Sr concentrations varied significantly among regions, among species, and among foraging guilds; this variability is strongly influenced by the Sr/Ca ratios in surface water from locations close to the region where the eggshells were collected. Sr concentrations and Sr/Ca ratios were significantly higher in bird eggshells from the Volta wildlife region in the San Joaquin Valley, California and in various locales from Arizona. Sr concentrations and Sr/Ca ratios in bird eggshells from other locations in the USA were lower than those detected in these two regions. Among foraging guilds, invertivores had the highest Sr concentrations and Sr/Ca ratios and carnivores had the lowest. In general, the Sr/Ca ratio increased strongly with increasing Sr concentrations (R = 0.99, P < 0.0001). There was a significant correlation (R = 0.58, P < 0.0001) between Sr/Ca ratios in water and the average Sr/Ca ratios in eggshells suggesting that these values could be determined from Sr/Ca ratios in water. Eggshell thickness was poorly correlated with Sr (R = 0.03) but had a significant and positive correlation with Ca and was more properly correlated by a quadratic equation (R = 0.50, Thickness = 2.13 − 0.02Ca − 3.07 * 10Ca). Our study provides further evidence that Sr accumulates significantly in the avian eggshell, in some regions at concentrations which could be of concern for potential negative effects on reproduction. We suggest that when assessing the effects of metals on avian reproduction in regions with high Sr deposits in rock and soil, Sr concentrations in the eggshell also should be measured to evaluate additional effects on thickness and reproduction. [ABSTRACT FROM AUTHOR]

Osprey (Pandion haliaetus) populations were adversely affected by DDT and perhaps other contaminants in the United States and elsewhere. Reduced productivity, eggshell thinning, and high DDE concentrations in eggs were the signs associated with declining osprey populations in the 1950s, 1960s, and 1970s. The species was one of the first studied on a large scale to bring contaminant issues into focus. Although few quantitative population data were available prior to the 1960s, many osprey populations in North America were studied during the 1960s and 1970s with much learned about basic life history and biology. This article reviews the historical and current effects of contaminants on regional osprey populations. Breeding populations in many regions of North America showed post-DDT-era (1972) population increases of varying magnitudes, with many populations now appearing to stabilize at much higher numbers than initially reported in the 1970s and 1980s. However, the magnitude of regional population increases in the United States between 1981 (first Nationwide Survey, ∼8,000 pairs), when some recovery had already occurred, 1994 (second survey, ∼14,200), and 2001 (third survey, ∼16,000-19,000), or any other years, is likely not a simple response to the release from earlier contaminant effects, but a response to multi-factorial effects. This indirect 'contaminant effects' measurement comparing changes (i.e., recovery) in post-DDT-era population numbers over time is probably confounded by changing human attitudes toward birds of prey (shooting, destroying nests, etc.), changing habitats, changing fish populations, and perhaps competition from other species. The species' adaptation to newly created reservoirs and its increasing use of artificial nesting structures (power poles, nesting platforms, cell towers, channel markers, offshore duck blinds, etc.) are two important factors. The timing of the initial use of artificial nesting structures, which replaced declining numbers of suitable trees at many locations, varied regionally (much later in the western United States and Mexico). Because of the increasing use of artificial nesting structures, there may be more ospreys nesting in North America now than ever before. Now, with the impact of most legacy organic contaminants (DDT, other organochlorine [OC] pesticides, polychlorinated biphenyls [PCB], polychlorinated dibenzo-p-dioxins [PCDD], polychlorinated dibenzofurans (PCDF]) greatly reduced or eliminated, and some osprey populations showing evidence of stabilizing, the species was proposed as a Worldwide Sentinel Species for evaluating emerging contaminants. Several emerging contaminants are already being studied, such as polybrominated diphenyl ethers (PBDE) and perfluorinated acids and sulfonate compounds (PFC). The many advantages for continued contaminant investigations using the osprey include a good understanding of its biology and ecology, its known distribution and abundance, and its ability to habituate to humans and their activities, which permits nesting in some of the potentially most contaminated environments. It is a top predator in most ecosystems, and its nests are relatively easy to locate and study with little researcher impact on reproductive success. [ABSTRACT FROM AUTHOR]

Ring-necked pheasants (Phasianus colchicus) are able to store dietary calcium as medullary bone, which they may mobilize for future eggshell synthesis. We define this mechanism as calcium-loading. Previous experiments on pheasants conducted to document the importance of calcium in limiting distribution did not account for calcium-loading. We hypothesized that calcium-loading could override experimental calcium treatments of the diet. We measured egg production, egg characteristics, and femoral mineral content for pheasants that were not calcium-loaded on 7 diets differing in calcium from 0.2% to 4.5% and compared these results to a similar study on calcium-loaded pheasants. We predicted that calcium-loaded pheasants would produce more eggs than those that were not calcium-loaded. We also predicted that there would be no significant difference between femur ash fractions in non-calcium-loaded pheasants, but that the ash fraction in calcium-loaded pheasants would differ significantly between the beginning and end of the experiment. Egg production was higher in calciumloaded pheasants above 2% dietary calcium. Femur ash fraction was not different in non-calcium-loaded pheasants but differed significantly before and after the experiment and between high (.2%) and low (,2%) dietary levels in calcium-loaded pheasants. Calcium-loading may account for short-term persistence of captive pheasants introduced on calcium-poor soils, followed by their eventual population failure. Managers may improve survival of captive pheasants before introduction by surveying habitat for adequate calcium and by calcium-loading. [ABSTRACT FROM AUTHOR]

Peregrine falcons were extirpated from the eastern United States by 1964 due to the effects of dichloro-diphenyl-trichlorethane (DDT) (Peakall and Kiff ). As a result of restoration efforts, peregrines have largely recovered in the region but remain a barometer of environmental contamination. In the course of monitoring nests, biologists in the mid-Atlantic states collected peregrine falcon eggs that failed to hatch. In the period 1993–1999, 93 eggs were collected from 66 nests in 31 locations in New Jersey, Pennsylvania, Delaware, Maryland, and Virginia. We analyzed eggs for organochlorine pesticides, PCBs, and metals, and calculated toxic equivalencies (TEQs) for dioxins and furans. Organochlorine contaminants were detected in eggs from all parts of the region. Although nest success in all parts of the region was good, the PCB TEQ in the Atlantic–New Jersey region was significantly related to nest success, and the regionwide PCB TEQ was nearly significant for nest success across the five-state area. dichloro-diphenyl-dichloroethylene (DDE), DDT, and total PCBs were negatively correlated with eggshell thickness, although eggshell thinning (10.4%) was not at a level associated with deleterious population effects. The five states represented in this study are productive for peregrine falcons and have contributed to the recovery of this species. However, the results suggest that Atlantic coastal peregrines might be subject to contaminant burdens that have the potential to decrease nest success and productivity. [ABSTRACT FROM AUTHOR]

Shell egg microbiology has been studied extensively, but little information is available on how modern U.S. processing conditions impact microbial populations. As regulations are being drafted for the industry, such information can be important for determining processing steps critical to product safety. Five different shell egg surface microbial populations (aerobic bacteria, yeasts and molds, Enterobacteriaceae, Escherichia coli and Salmonella) were monitored at 12 points along the processing line (accumulator, prewash rinse, washer 1, washer 2, sanitizer, dryer, oiler, scales, two packer head lanes, rewash entrance, and rewash exit). Three commercial facilities were each visited three times, a total of 990 eggs were sampled, and 5,220 microbiological samples were subsequently analyzed. Although variations existed in concentrations of microorganisms recovered from each plant, the patterns of fluctuation for each population were similar at each plant. On average, aerobes, yeasts and molds, Enterobacteriaceae, and E. coli prevalence were reduced by 30, 20, 50, and 30%, respectively, by the end of processing. The microbial concentrations (log CFU per milliliter) in the egg rinse collected from packer head lanes were decreased by 3.3, 1.3, 1.3, and 0.5, respectively, when compared with those of rinses collected from eggs at the accumulator. Salmonella was recovered from 0 to 48% of pooled samples in the three repetitions. Higher concentrations of Salmonella were recovered from preprocessed than from in-process or ready-to-pack eggs. These data indicate that current commercial practices decrease microbial contamination of egg shell surfaces. [ABSTRACT FROM AUTHOR]

Egg-capping is the slipping of a hatched eggshell fragment over an intact shell. It is a rare phenomenon among avian species, probably because most eggs in the same clutch hatch synchronously, are similar in size, and parents typically remove debris--including shell fragments--from nests. Hatching asynchrony and egg-size differences are typically more pronounced in the context of interspecific brood parasitism, making conditions for egg-capping more likely. Indeed, egg-capping of host eggs occurred in 33% of clutches of Eastern Phoebes (Sayornis phoebe) parasitized by Brown-headed Cowbirds (Molothrus ater), always by the earlier hatched cowbird's eggshell, whereas it was not detected in nonparasitized clutches near Ithaca, New York. To determine experimentally if host parents rejected their own eggs capped by the parasite's shell, cowbird shell fragments were introduced into nonparasitized phoebe clutches either as slipped over intact phoebe eggs (caps) or simply placed into the nests (noncaps). The latency for cowbird egg-fragments to disappear was greater for caps (1-13 days) because all noncaps were removed in <1 day. Whether phoebe eggs hatched was also related to the outcome of the capping treatments: eggs that remained capped for >1 day had a greater probability of hatching failure (0.6) than noncapped eggs (0). Those data suggest that egg-capping by shell-fragments of earlier hatched cowbird eggs reduces phoebes' reproductive success and may represent a fitness cost to hosts in other parasitized species as well. [ABSTRACT FROM AUTHOR]

Presents a study which applied organochlorine analysis to determine the eggshell thickness of California clapper rail from tidal marshes of south San Francisco Bay, California. Effect of organochlorine contamination on birds in San Francisco Bay; Methods used; Results; Discussion.

Reports on whether poultry shell eggs are a major reservoir of Salmonella enteritidis in Arkansas. Purchase of shell eggs for culturing; Reevaluation of previously obtained telephone follow-up on 204 patients with Salmonella infections; Shells contaminated with Salmonella heidelberg.

The article discusses a procedure developed by the U.S. Department of Agriculture's (USDA) Agricultural Research Service (ARS) to help the USDA'S Agricultural Marketing Service identify microcracks in egg shells. According to the article, the cracks are a food-safety concern because of the pathogens that can pass through the cracks and contaminate the eggs. High-frequency analysis is used at many egg-processing plants to listen for cracks, while other plants use human graders to inspect the eggs. ARS's pressure chamber technology and the specialized camera that captures images of the eggs are discussed.

The article reports on the research made by Geoffrey Birchard of George Mason University in Virginia and Charles Deeming of Great Britain regarding bird eggs in 2009. It states that they conclude that eggshells must be strong in order to avoid being crushed when birds sit on them and they must not be too strong that the chicks could not break out of their shells. It cites that they found out that eggs are bigger, but have thinner shells, because there are only few males that incubate eggs.