Prevalence of high-risk egg-preparation practices in restaurants that prepare breakfast egg entrées: an EHS-Net study

Salmonella enterica serotype Enteritidis (SE) is a common cause of foodborne illness in the United States. Foods prepared with raw shell eggs have often been associated with SE outbreaks. The federal government published the Egg Safety Action Plan in December 1999 that called for reduction of egg-preparation practices that may contribute to the survival and proliferation of SE. In seven states, an interview and brief site evaluation of 153 restaurants that prepare eggs during all hours of operation was conducted by the Environmental Health Specialists Network to determine the prevalence of such practices. Fifty-four percent (83 of 153) of restaurants pooled raw shell eggs not intended for immediate service. These pooled eggs were held a median of 4 h for scrambled eggs, 5.5 h for omelets, and 6 h for pancakes and French toast. Nearly 26% (39 of 152) of restaurants reported storing eggs at room temperature, and 5% (7 of 152) stored eggs on ice or in cold-water baths before cooking. Generally, eggs were cooked to 72 to 83 degrees C, which is above the recommended final cook temperature of 63 to 68 degrees C. Employees reported sanitizing utensils used to prepare eggs less than once every 4 h in 42% (57 of 136) of restaurants. Several areas were identified in which further emphasis might reduce egg-associated SE infections in accordance with Healthy People 2010 goals.     

Texture and Microstructure of Cooked Whole Egg Yolks and Heat-Formed Gels of Stirred Egg Yolk

Hardness, cohesiveness, and springiness of heated intact egg yolks were determined by an Instron compression test. Hardness increased as temperature was increased from 75° to 90°C and as time of heating was increased from 10 to 30 min. Cohesiveness and springiness increased as temperature was increased from 75° to 80°C and as time was increased from 10 to 30 min. Egg yolks from cooked shell eggs were lower in all textural parameters than gels formed from stirred egg yolk. Low scores for cohesiveness and springiness were indicative of the crumbliness of yolk from cooked shell eggs; crumbliness was attributed to structural characteristics. The microstructure consisted of adjoining polyhedral grains, which showed no evidence of crosslinking. Grains appeared to be equivalent to yolk spheres, ranging in size from 40 to 100 μm. The structure of a stirred yolk gel consisted of a highly crosslinked protein matrix containing spheres (5–35 μm) and granules (l–2 μm).     

The effect of degree of doneness of beef steaks on consumer acceptability of meals in restaurants

A total of 3554 consumers, who selected beef steak menu items at nine restaurants, were surveyed on their attitudes to beef and their assessment of beef steak meals. Consumers were asked to describe the menu item, their assessment of steak size and the degree of doneness of the steak, both as they ordered it and how they perceived it was delivered. Consumers rated the meal for tenderness, taste, overall satisfaction, value for money and intent to repurchase, and were also asked their sex, age and attitude to beef. The average ordered degree of doneness for all consumers was medium. A total of 30% of consumers considered they did not receive their steaks cooked to their ordered degree of doneness. The interaction between ordered and delivered degree of doneness had a highly significant (P < 0.001) effect on consumer scores for tenderness, taste, overall satisfaction, value for money and intent to repurchase. The maximum consumer scores were obtained when steaks were cooked to their ordered degree of doneness. If steaks were perceived not delivered as ordered, there was a decline in all consumer scores (P < 0.001), with a greater penalty for over- than under-cooking (P < 0.001). This study showed the dramatic penalty in consumer satisfaction for a chef failing to deliver a steak cooked to the ordered degree of doneness.     

Consumer acceptance of new strawberry vinegars by preference mapping

Consumers’ acceptance of new strawberry vinegars was evaluated, and trained panellists described their sensory profiles. Four strawberry vinegars, three produced from puree and one from cooked must, were evaluated jointly. Due to obtaining the highest percentage of consumer acceptance, cooked strawberry must vinegar was considered to be the best. This vinegar stood out in general impression, raisin, and liqueur attributes. Internal preference maps confirmed a higher acceptance level for the strawberry vinegars over commercial vinegar. External preference mapping, obtained by PLS2 analysis, revealed that the main sensory attributes driving consumers’ preferences are raisin, toasted caramel, spicy, and liqueur aroma.     

Acceptability of boar meat by consumers depending on their age, gender, culinary habits, and sensitivity and appreciation of androstenone odour

Sensitivity of the consumers to androstenone, evaluated as the degree of smell (strong/weak) perceived by smelling the pure compound, is important in determining their acceptability of pork with different levels of androstenone and skatole. However, 8% (3.3% women and 16.2% men) of highly sensitive consumers like this odour, and 12.7% (9.1% women and 15.9% men) of mildly sensitive/insensitive consumers dislike it. The effect of the appreciation (like/dislike) of the smell in the acceptability of pork samples has not been reported previously. The aim of this paper is to ascertain if this liking for androstenone odour affects pork acceptability as well as the gender, age, and culinary habits of the consumers. Consumers evaluated the flavour and odour of five cooked and reheated samples, and recorded their acceptability on a 7-step scale. Results showed that acceptability of pork increases when the frequency of cooking and eating fresh pork are higher. The acceptability also differed depending on the sensitivity of the consumer within each age group. Appreciability of androstenone odour discriminates more than sensitivity in consumers’ acceptance of pork.     

Thermoultrasonication Eliminates Salmonellae from Intact Eggshells without Changing the Functional Properties of their Components

We have previously reported that the simultaneous application of heat and ultrasound (thermoultrasonication) to intact eggs allows a reduction in the number of Salmonella enterica serovar Enteritidis present on the shell to a safe hygienic level in less severe conditions (temperature and time) than those usually recommended for common pasteurization. In the present work, the effect of thermoultrasonication on selected functional properties of egg compounds (shelf‐life, emulsifying and foaming capacities, emulsion and foam stabilities, texture properties of egg white gel, breakage resistance of shell, and sensory properties of cooked egg) has been studied under the conditions previously defined (54 °C for 5 min) for the developed treatment. No significant differences were obtained in any of properties assayed between thermoultrasonicated and untreated (fresh) eggs. We concluded that it is possible to pasteurize the surface of intact eggs by applying a thermoultrasonic treatment yielding a product with a safe level of S. Enteritidis and cause negligible damage to the thermolabile egg components.     

Effects of Lactobacillus cultures on performance of laying hens,and total cholesterol,lipid and fatty acid composition of egg yolk

BACKGROUND: The use of antibiotic growth promoters in animal feeds is not approved for laying hens in many countries, and economically feasible biological measures which include probiotics are developed to improve hen performance. The present study investigated the effects of probiotics on hen performance for a 48‐week period and the cholesterol, total lipid and fatty acid composition of egg yolk at 24, 28 and 32 weeks of age. RESULTS: Egg weight of Lactobacillus culture (LC)‐fed hens was significantly (P < 0.05) greater than that of control hens throughout the laying period. From 20 to 44 weeks of age, LC‐fed hens produced a significantly (P < 0.05) lower percentage of small eggs and a higher percentage of large eggs, and from 45 to 68 weeks of age a significantly (P < 0.05) lower percentage of medium eggs and a higher percentage of large and extra‐large eggs than control hens. Significantly (P < 0.05) less cholesterol was found in egg yolks of hens fed LC at 24 and 28 weeks of age, but not at 32 weeks of age. The total lipid content and the fatty acid composition of egg yolks were similar between the treatments at 24, 28 and 32 weeks of age, except for stearic acid (C_{18 : 0}), which was significantly reduced in the egg yolk of LC‐fed hens at 28–32 weeks of age. CONCLUSION: The greatest benefit of LC was in increasing egg weight and improving egg size by influencing a shift from small and medium to large and extra‐large eggs. Copyright © 2008 Society of Chemical Industry     

Analysis of thermal processing of liquid eggs using a high frequency ohmic heating: Experimental and computer simulation approaches

Experimental and simulated approaches combining an ohmic heating (OH) process and an external heating system for the pasteurization of liquid egg whites, yolks, and whole eggs were evaluated in this study. 3D computer simulation models were developed for each approach using COMSOL Multiphysics 5.6 to visualize the temperature and distribution of degrees of pasteurization at several cross sections. From both the hot and cold spots of the samples, the temperature, thermal protein non-denaturation ratio (X), and pasteurization profiles were estimated. Color changes were also evaluated using a computer vision system (CVS). The heating conditions were optimized according to a high constant X value, a low total color difference value (ΔE < 3), and certain pasteurization standards for each sample. OH treatment combined with concurrent external heating approaches reduced the process time and prevented local overheating. These results are of potential value for the design of ohmic pasteurization systems for liquid eggs.     

Preference ranking of colour in raw and cooked shrimps

The reddish colour to shrimp, which has been associated with its high quality, is one of the major factors for its acceptability by consumers. The aim of this work was to analyse consumer preference regarding colour in raw and cooked shrimps. Farmed shrimps Litopenaeus vannamei (13.8 + 1.16 g) were fed with control or supplemented food (60 ppm of carotenoids). The shrimp samples were analysed in naked eye, confirmed by colorimetry and sorted in the following categories: dark grey (L* 27.99; h 168.16), grey (L* 32.58; h 124.60), and light grey (L* 36.2; h 119.35) for raw shrimps; and intense orange (L* 61.49; h 54.69), orange (L* 65.97; h 57.79) and light orange (L* 72.65; h 70.17) for cooked shrimps. A preference ranking test was performed with 35 judges invited to rank the samples in descending order of preference. Consumers prefer lighter raw shrimp (light grey and grey) and brightly orange cooked shrimps (orange and intense orange), which indicates that supplementing shrimp food for pigmentation should be followed by improving its acceptance by consumer. These results indicate a challenge for the shrimp industry, as the lightest raw shrimps are also not so brightly orange coloured after cooking.     

A review on egg pasteurization and disinfection: Traditional and novel processing technologies

Salmonella Enteritidis is a pathogen related to many foodborne outbreaks involving eggs and egg products. Regulations about whether eggs should be pasteurized are very different and inconsistent worldwide. In the United States, eggs are not required to be pasteurized. Hence, less than 3% of the eggs in the country are pasteurized. The standard pasteurization method (57°C, 57.5 min) uses a long thermal process that increases the cost of the product and affects its quality. Foodborne outbreaks can be reduced if eggs are properly pasteurized to inactivate Salmonella spp. However, the technology to pasteurize eggs needs to offer a faster and more reliable method that can be scaled up to industry settings at a low cost and without affecting product quality. Several novel technologies have been tested for eggshell disinfection and egg pasteurization. Some thermal technologies have been evaluated for the pasteurization of eggs. Microwave has limited penetration depth and is a technical challenge for egg pasteurization. However, radio frequency can penetrate eggshells effectively to inactivate Salmonella, considerably reduce processing time, and maintain the quality of the product. Nonthermal technologies such as ultraviolet, pulsed light, cold plasma, ozone, pressure carbon dioxide, electrolyzed water, and natural antimicrobials have been explored for surface cleaning of the intact egg as alternatives without affecting the internal quality. This review presents some of these novel technologies and the current challenges. It discusses the possible combination of factors to achieve the egg's internal pasteurization and the eggshell's disinfection without affecting the quality at a low cost for the consumer.     

3种家禽类品种间生熟蛋黄挥发性风味物质的差异研究

目的比较北京油鸡、白来航鸡、北京鸭的生蛋黄风味物质差异,同时探究生、熟鸭蛋黄的风味物质差异。方法样本选用相同饲养条件下北京油鸡、白来航鸡所产鸡蛋,不同饲养条件的北京鸭所产鲜蛋,主要运用气相色谱-质谱技术,研究分析3种生蛋黄挥发性风味物质差异。同时比较了鸭蛋生、熟蛋黄风味物质的差异性。结果 3种生蛋黄和1种熟蛋黄中均检测到烷烃类物质、醛类物质、酮类物质、醇类物质、酯类物质、芳香族类物质、烯烃类物质、杂环类物质和酸类物质。其中芳香族类物质含量占比最大,北京油鸡生蛋黄、白来航鸡生蛋黄、北京鸭生蛋黄分别为37.10%、36.90%、34.31%;酸类物质含量少、差异大,含量占比北京油鸡生蛋黄、白来航鸡生蛋黄、北京鸭生蛋黄分别为0.55%、0.49%、2.61%。北京鸭生、熟蛋黄鉴定出9类挥发性风味物质,熟蛋黄111种,生蛋黄108种。结论芳香族物质、酯类物质、酸类物质对禽蛋风味影响大,物质含量不同是禽蛋黄风味不同的主要原因,生蛋黄风味物质直接影响了熟蛋黄风味。     

Quality of shell eggs pasteurized with heat or heat-ozone combination during extended storage

The physical quality and functionality of shell eggs, pasteurized with heat or a combination of heat and ozone, were assessed during eight weeks of storage at 4 or 25 °C. Shell eggs were treated as follows: (1) immersion heating that mimics commercial pasteurization processes (egg internal temperature of 56 ± 0.1 °C for 32 min), or (2) a newly developed combination process comprised of heating (56 ± 0.1 °C, internal, for 10 min) followed by gaseous ozone treatment. Eggs were tested for yolk index, Haugh units, albumen pH, albumen turbidity, and percent overrun. Additionally, albumen samples were assayed for lysozyme activity and free sulfhydryl group content, and were analyzed using differential scanning calorimetry and Fourier transform infrared (FTIR) spectroscopy. Both processed and unprocessed eggs maintained superior quality when stored at 4 °C, as opposed to 25 °C. Pasteurization, regardless of method, led to superior maintenance of Haugh units during storage but also increased albumen opacity and decreased albumen overrun. Detrimental effects on quality markers were more severe in heat-pasteurized eggs than those treated with the ozone-based process. Pasteurization of shell eggs by either process did not affect lysozyme activity or sulfhydryl group content. Changes in protein secondary structure, as indicated by FTIR analysis, suggest that the ozone-based process is less damaging to albumen proteins than is the heat-alone process. In conclusion, heat-ozone pasteurization, by virtue of its less severe heat treatment, yields a safe final product that more closely resembles untreated shell eggs.     

Effect of hot water treatment of in-shell pecans on physicochemical properties and consumer acceptability of roasted pecan kernels

The effect of hot water pre-treatment of in-shell pecans on physicochemical properties, consumer acceptance and purchase intent of dehulled and roasted kernels was evaluated. In-shell pecans were first subjected to hot water at 70, 80 and 90 °C for 8.6, 6.6 and 4.6 min respectively and kernels were later dry roasted at 160 °C for 10 min. The physicochemical properties of hot water treated and untreated nuts, before and after roasting were determined. Furthermore, consumer acceptance and purchase intent of the roasted kernels were determined. Hot water treatment, alone and subsequent roasting had minimal effect on pecans’ physicochemical properties. Consumers liked (P < 0.05) the colour and aroma of treated pecans. No effect (P > 0.05) of pre-treatment was observed on the acceptability of other sensory attributes. Safety claim increased treated pecans’ overall liking; however, it decreased purchase intent. Hot water treatment showed promise as a post-harvest microbial intervention strategy without affecting the physicochemical properties and consumer acceptability.     

Tocopherols, Retinol and Carotenes in Chicken Egg and Tissues as Influenced by Dietary Palm Oil

Incorporation of palm oil (PO) increased the α-and γ-tocotrienol content of eggs, liver, meat and adipose tissue. Total tocotrienols were higher in eggs, liver and adipose tissue of hens fed 1.5% PO than those fed 3.5% PO. An increase in retinol was observed in the eggs, liver and dark meat of hens fed PO diet. Feeding diets containing 1.5 or 3.5% PO increased the α-and β- carotenes in eggs and liver tissue. However, carotenoids were not detected in white meat, dark meat or adipose tissue. Dark meat incorporated higher levels of tocopherols and retinol than white meat. The diets had no effect on egg or yolk weight. Egg yolks from hens fed PO had higher yolk color than those without PO. Addition of tocopherol mix in the control diet increased total tocopherol content in all tissues.     

Simultaneous depolymerization and decolorization of chitosan by ozone treatment

ABSTRACT:  Currently, depolymerization and decolorization of chitosan are achieved by chemical or enzymatic methods, which are time consuming and expensive. Ozone has been shown to be able to degrade macromolecules and remove pigments due to its high oxidation potential. In this study, the effects of ozone treatment on depolymerization and decolorization of chitosan were investigated. Crawfish chitosan was ozonated in water and acetic acid solution for 0, 5, 10, 15, and 20 min at room temperature with 12 wt% gas. In this study, the effects of ozone treatment on depolymerization and decolorization of chitosan were investigated by measuring the molecular weight, viscosity, and color of chitosan. The color of ozone-treated chitosan was analyzed using a Minolta spectrophotometer. The degree of deacetylation was determined by a colloid titration method. Molecular weight of ozone-treated chitosan in acetic acid solution decreased appreciably as the ozone treatment duration increased. Ozonation for 20 min reduced the molecular weight of the chitosan by 92% (104 kDa) compared to the untreated chitosan (1333 kDa) with a decrease in viscosity of the chitosan solution. Ozonation for 5 min markedly increased the whiteness of chitosan with a molecular weight of 432 kDa; however, further ozonation resulted in development of yellowness. In the case of the ozonation in water, there were no significant differences in the molecular weight and color between ozone-treated chitosans. This study showed that ozone can be used to modify molecular weight and remove pigments of chitosan without chemical use in a shorter time and with less cost.     

Consumer Assessment of Beef Tenderloin Steaks from Various USDA Quality Grades at 3 Degrees of Doneness

A consumer study was conducted to determine palatability ratings of beef tenderloin steaks from USDA Choice, USDA Select, and USDA Select with marbling scores from Slight 50 to 100 (USDA High Select) cooked to various degrees of doneness. Steaks were randomly assigned to 1 of 3 degree of doneness categories: very‐rare, medium‐rare, or well‐done. Consumers (N = 315) were screened for preference of degree of doneness and fed 4 samples of their preferred doneness (a warm‐up and one from each USDA quality grade treatment in a random order). Consumers evaluated steaks on an 8‐point verbally anchored hedonic scale for tenderness, juiciness, flavor, and overall like as well as rated steaks as acceptable or unacceptable for all palatability traits. Quality grade had no effect (P > 0.05) on consumer ratings for tenderness, juiciness, flavor, and overall like scores, with all traits averaging above a 7 (“like very much”) on the 8‐point scale. In addition, no differences (P > 0.05) were found in the percentage of samples rated as acceptable for all palatability traits, with more than 94% of samples rated acceptable for each trait in all quality grades evaluated. Steaks cooked to well‐done had lower (P < 0.05) juiciness scores than steaks cooked to very‐rare or medium‐rare and were rated lower for tenderness (P < 0.05) than steaks cooked to a very‐rare degree of doneness. Results indicate consumers were not able to detect differences in tenderness, juiciness, flavor, or overall like among beef tenderloin steaks from USDA Choice and Select quality grades.