Imaging system with modified-pressure chamber for crack detection in shell eggs

To detect checks and/or cracks in shell eggs, the egg industry is using high-speed acoustic systems. Prior to shipment, human graders candle a small subset of eggs to ensure that the high-speed systems are operating within specifications for a given grade of egg (e.g., Grade A large eggs). In addition to visual inspection, graders also listen for a dull, flat sound as an indicator of a crack when tapping eggs together. However, very small cracks, or micro-cracks can go undetected by the human graders. A method to detect egg checks/cracks with an imaging camera was developed. The system consisted of an imaging camera positioned above a clear inspection chamber that housed an egg and was illuminated from underneath. The chamber was designed so that a short, quick vacuum could be pulled to enhance the crack detection. High-resolution monochromatic images were collected at atmospheric pressure and under negative pressure. The negative pressure gradient was used to briefly open any existing cracks without inducing any new cracks in an intact egg. Initially, eggs were manually rotated three times to image the whole surface of the egg. The ratio of a negative-pressure image divided by an atmospheric-pressure image was used to highlight the cracks and simple image processing was used to identify a crack. A total of 80 cracked and 80 intact eggs were imaged with the system. Only one cracked egg was not detected, and this was because the crack was located on the air-cell end of the egg and was not visible by the camera. Thus, the system was 98.75% accurate in identifying cracked eggs and 100% accurate in identifying intact eggs. This initial phase of the research was successful and the system is being scaled up to image multiple eggs at a time.

Motion compensated image processing and optimal parameters for egg crack detection using modified pressure

Shell eggs with microcracks are often undetected during egg grading processes. In the past, a modified pressure imaging system was developed to detect eggs with microcracks without adversely affecting the quality of normal intact eggs. The basic idea of the modified pressure imaging system was to apply a short burst of vacuum within a transparent chamber in order to cause a momentary and forced opening in the egg shell with a crack and thus to utilize the changes in image intensities during this process. The intensity changes from dark to bright in the shell surface were recorded by a high-resolution digital camera and processed by an image ratio technique. However, the performance of the imaging system was compromised by both false readings due to motion of intact eggs relative to the camera and an improper selection of parameter values for the detection algorithm. First, a machine vision technique based on motion estimation of individual eggs was developed to compensate any motion errors present on images and thus reduce false crack-detection readings. The simulation results of the developed motion estimation and compensation technique with 3,000 eggs showed no false errors. Second, the receiver operating characteristic (ROC) curve was used to evaluate and compare the performance of the crack-detection algorithm under varying parameters (ratio and detection-tolerance thresholds) and to find the optimal parameter values. The area under the ROC curve (AUC) was used to compare the performance under varying parameter values. The minimum distance and Youden index criteria were used to find the optimal values from the ROC curve. The minimum distance criterion found the optimal parameters at 1.11 and 20 (or 1.1 and 25) for the ratio and detection-tolerance thresholds, respectively. The true positive and false positive rates at the optimal conditions were 98.91 and 0.14 %, respectively.     

High voltage atmospheric cold plasma decontamination of Salmonella enteritidis on chicken eggs

Salmonella enteritidis (SE) accounts for more than 70% of Salmonella spp. infections in humans with a primary source being chicken eggs, that can result from post-lay SE cross-contamination of the shell from contaminated equipment or the environment. The objective of this study was to apply a HVACP treatment that can achieve a minimum 5-log reduction in SE on the surface of artificially inoculated shell eggs with an initial bacterial load of 10⁸ CFU/egg, after a previous disinfection. Optimized HVACP treatment conditions were an indirect treatment with air at 60% humidity at 100 kV for one minute treatment and six hours post-treatment or alternatively, five minutes of treatment and four hours post-treatment. Egg quality parameters of Haugh unit (HU), pH, color, and vitelline membrane and shell strength were tested under the optimized conditions and showed no significant difference (p > 0.05) between treated and untreated eggs.Industrial relevance: Missing information for a possible scale up of a cold plasma system for egg surface decontamination has been addressed by an optimization of HVACP treatment focused on treatment and post-treatment time, essential parameters to have into account in the food industry. These results demonstrate that HVACP is an effective decontamination method for SE on chicken shell eggs and provides a baseline for a future scale up of the process, showing that different combinations of treatment variables can achieve the desired decontamination without affecting to key quality parameters of the egg such as Haugh Unit or vitelline membrane strength.     

Efficacy of disinfection of shell eggs externally contaminated with Salmonella enteritidis. Implications for egg testing.

Experimental contamination of the surface of shell eggs by dipping in a culture of Salmonella enteritidis resulted in the presence of Salmonella enteritidis in/on the shells as well as shell membranes but not in the egg content. Disinfection with Lugol's solution, chlorhexidine, ethanol, quarternary ammonium solutions or flaming after dipping in ethanol failed to achieve complete decontamination of the shell and membranes with resulting false positives when eggs were broken for culturing of the content. Dipping eggs for three seconds in boiling water resulted in complete destruction of Salmonella enteritidis in shells and membranes but sometimes caused the eggs to crack. A method of aseptically opening eggs without risk of contaminating the content from the shell or membrane was developed. Salmonella enteritidis deposited in/on the shell and membranes did not multiply during storage of the eggs at 20 degrees C for four weeks, the counts seemed to decrease. No Salmonella enteritidis was detected in the contents of any contaminated eggs.     

Synergistic action of transglutaminase and high pressure on chicken meat and egg gels in absence of phosphates

The effects of simultaneous application of microbial transglutaminase (MTGase) and high pressure (HP) (500, 700 and 900 MPa/40 °C/30 min), only pressure under the same conditions or heat (75 °C/30 min) were investigated on chicken batters with the addition of egg components and without phosphates. MTGase gels (700 and 900 MPa) showed marked increases in textural parameters compared to gels without enzyme (NE) or those obtained by heat. The addition of enzyme did not show differences between gels obtained at 700–900 MPa; however, gels obtained at 500 MPa were darker and more reddish than those obtained by heat. MTGase gels were more homogeneous and compact. Thermal analysis revealed that pressure levels above 700 MPa caused as much denaturing as did heat. The microstructure and texture of MTGase gels suggest that a higher amount and heterogeneity of crosslinks was produced when meat and egg proteins were treated in the presence of MTGase under specific conditions of pressure.     

盐水浸泡腌制过程中鸭蛋壳裂的成因

研究了用盐水浸泡法腌制过程中,鸭蛋盐分含量、蛋重、蛋壳比重、蛋壳厚度、气孔数、气室直径、单位面积蛋壳脆性、强度和蛋壳截面微观结构的变化。结果表明,5周内,随着盐分含量的增加,鸭蛋重从61.85 g增加至63.16 g;蛋壳比重、蛋壳厚度均无明显变化,气室直径稍有变化;气孔数从24.93个/0.25 cm2减少至10.40个/0.25 cm2;蛋壳脆性和强度分别从445.2N和1461.2N降至240.6N和446.1N;蛋壳强度从44.504 N降至34.452 N。鸭蛋蛋壳比重低于10%、蛋壳厚度低于0.355 mm、蛋形指数在1.380～1.460低强度范围内腌制期间易裂壳。腌制5周后,蛋壳截面纹路多、有不规则断层;裂壳蛋的壳截面显粗糙、有不规则断裂,乳突排列不均,壳膜结构松散。鸭蛋壳裂的产生是由新鲜鸭蛋壳质量决定,盐水腌制破坏了蛋壳的微观结构和脆性、强度,并对壳裂起到了促进作用。     

Evaluation of microstructure and quality characteristics of microwave-dried instant noodles enriched with chicken meat,egg yolk,and seaweed

The effects of chicken meat, egg yolk, and seaweed supplementation on microwave-dried instant noodles were investigated to develop protein-enriched instant noodles. The influence of chicken meat significantly (P?≤?0.05) increased the optimum cooking time and water absorption. Additionally, egg yolk improved the noodle quality by decreasing the cooking loss from 6.51 to 4.25% and increasing the maximum tension force and distance from 0.13 to 0.16 N and from 16.83 to 24.69 mm, respectively, which contrasted with the decrease in the maximum tension force and distance caused by seaweed addition. Scanning electron micrographs of the chicken addition presented large porous structures, while the egg yolk addition resulted in uniform porous structures with a finer connective network; confocal scanning laser micrographs also confirmed good protein distribution. Finally, instant noodles supplemented per 100 g of flour with chicken meat (10 g), egg yolk (10 g), and seaweed (2 g) were selected as optimal. The protein content significantly (P?≤?0.05) increased from 11.42 to 16.73 g per 100 g dry matter, which was higher than in traditional wheat-based instant noodles and this developed product was preferred by panelists. This knowledge can support innovation in the development of instant noodles with a higher protein content.     

Simultaneous application of transglutaminase and high pressure to improve functional properties of chicken meat gels

Low-fat protein gels obtained by pressure are softer than those processed by conventional heat treatment. In this study, microbial transglutaminase (MTGase) (0.3%) was added to chicken batters in order to investigate the combined effect of pressure and enzyme on the functional properties of gels. Batters of meat with egg proteins were treated at 500 MPa for 30 min at 40 °C and then heated at 75 °C for 5 min to inactivate the enzyme. Treated samples showed, under confocal microscopy, a more compact and homogeneous microstructure and exhibited a notable increase in hardness and chewiness as compared to controls that were pressurized but contained no MTGase. They were also harder, more chewy and springy but had a similar cohesiveness and cutting force to those obtained by heat alone.     

鸡蛋外部品质与其呼吸强度的相关关系

鸡蛋贮藏保鲜问题一直是蛋品行业研究的重点,已有研究表明鸡蛋品质与其呼吸强度存在密切联系。为了 更进一步明确鸡蛋品质与其呼吸强度之间的关系,本研究选取同一品种但不同外部品质指标的鸡蛋作为实验样品, 利用呼吸测定仪测量鸡蛋的呼吸强度,分析鸡蛋品质与其呼吸强度之间的关联。通过SPSS 19.0软件分别比较分析 鸡蛋质量、蛋形指数、蛋比重、蛋壳质量、蛋壳厚度、蛋壳比例（蛋壳质量与鸡蛋质量百分比）以及蛋壳强度对鸡蛋 呼吸强度的影响。结果表明：鸡蛋质量和蛋形指数与呼吸强度之间显著正相关（P＜0.05）;蛋壳厚度和蛋壳比例与 呼吸强度之间显著负相关（P＜0.05）;而蛋壳强度、蛋壳质量以及蛋比重与呼吸强度间相关性不显著（P＞0.05）; 此外,蛋比重与蛋壳强度、蛋壳厚度以及蛋壳比例均极显著正相关（P＜0.01）;蛋壳厚度与蛋壳强度极显著正相 关（P＜0.01）。总之,在鸡蛋外部品质中,鸡蛋质量、蛋形指数、蛋壳厚度及蛋壳比例对鸡蛋呼吸强度影响最大。     

Coagulation of Egg White of Soft-Shell Turtle (Pelodiscus Sinensis) at High Pressure or High Temperature

The coagulations of soft-shell turtle egg white at high pressure or at high temperature were investigated and compared to chicken egg white. Unlike chicken egg white, no coagulation of soft-shell turtle egg white was observed after high-pressure processing (HPP; 200–600 MPa) or heating treatment (75°C). Basic amino acids, histidine, lysine, and arginine were present at higher percentages in soft-shell turtle egg white proteins than in chicken egg white proteins. Sodium dodecyl sulfate/polyacrylamide gel electrophoresis showed that the intensities of soft-shell turtle egg white components were balanced, there were more components with high molecular mass in soft-shell turtle egg white, and that aggregates formed in both soft-shell turtle egg white and chicken egg white. This work revealed some differences in soft-shell turtle egg white compositions. The low protein content in egg white was responsible for the non-coagulation of soft-shell turtle egg white in response to high pressure or temperature.     

油桐籽破壳力学特性及主要影响因素研究

为研究适用于油桐籽的高效脱壳设备,开展油桐籽破壳力学特性研究,分析破壳力作用形式、油料粒径大小对其破壳效果的影响。结果表明:油桐籽在顶压、侧压和俯压不同挤压变形时,其籽壳裂纹只有一条且各处同时出现小裂纹,裂纹均沿施力方向延伸,裂纹宽度随着压力的增加而增大;在匀速加载过程中,无论是顶压、侧压还是俯压,在未破裂时压力随着变形量的增加而呈现线性增加,当加载到超过外壳所能承受的最大载荷,外壳发生破裂,从而导致破壳力急剧下降,曲线中断;破壳力的大小受力的作用形式及油桐籽粒径的影响,在相同的加载方式下,破壳力随着油桐籽等级的增大而增加,但不明显;在油桐籽大小等级相同的情况下,顶压方式破壳所需要的破壳力和侧压方式基本相同,但破壳力明显小于俯压方式,即油桐籽在一对集中力作用下顶压方式和侧压方式更易破裂。     

Computational investigation of the effect of orientation and rotation of shell egg on radio frequency heating rate and uniformity

The objective of this work was to computationally investigate radio frequency (RF) heating rate and uniformity of shell egg as affected by orientation and rotation. To do this, a multiphysics model was developed using COMSOL to simulate RF heating of a vertically oriented non-rotating shell egg. This model was experimentally validated against temperature measurements taken at three different internal locations within the egg. Simulations were then performed using the validated model with both non-rotating and rotating egg for different orientations (vertical and horizontal). Rotation of egg was incorporated into the model by rotating the RF system around the stationary egg instead of rotating the egg. Temperature-dependent material properties of the yolk, albumen and shell within a temperature range of 20 to 70 °C were used in the model. Simulated temperature uniformity index (STUI) values were calculated to evaluate the effect of orientation and rotation on heating uniformity. The results showed that heating was more uniform when shell egg was oriented horizontally rather than vertically. However, rotation did not further improve heating uniformity of the horizontally-oriented egg. Although heating uniformity was improved when the vertically-oriented egg was rotated, concentrated heating around the air cell could not be avoided.     

合肥市售鸡蛋壳表面与内容物沙门氏菌污染的 检测及其分离株耐药性分析

目的 了解市售鸡蛋壳表面、内容物中沙门氏菌的污染情况及分离菌株的血清型分布与耐药性。方法 采用沙门氏菌常规检测法并结合PCR技术, 对采自合肥市农贸市场、超市的100枚鸡蛋进行检测; 利用国标法和K-B 纸片法对分离株进行血清型鉴定和抗生素药物敏感试验。结果 蛋壳表面沙门氏菌检出率为10%(10/100), 蛋内容物沙门氏菌检出率为1%(1/100); 11株沙门氏菌分离株血清型均为鸭沙门氏菌; 14种抗生素药物敏感试验中, 对青霉素100%耐受, 链霉素18.2%耐药, 36.4%中等耐药率, 其余抗生素均敏感。 结论 合肥市售鸡蛋壳表面的沙门氏菌检出率高于蛋内容物, 抗生素选择压力导致不同地区沙门氏菌分离株的血清型和耐药性有所不同。     

Antibacterial activity of Bacillus amyloliquefaciens phage endolysin without holin conjugation

To characterize the enzymatic activity and antibacterial activity of endolysin encoded by a Bacillus amyloliquefaciens phage, the open reading frame encoding endolysin was amplified by PCR and cloned into the expression plasmid pET21d(+). The resultant plasmid was used to transform Escherichia coli JM109(DE3). Production of endolysin in the cytosol facilitated cell lysis without coproduction of holin, which is considered to degrade or alter the cytoplasmic membrane. The phage endolysin was overexpressed and purified. Although the specific activity of the purified phage endolysin towards lyophilized Micrococcus luteus cells was 1/11 of the activity of chicken egg white lysozymes, the endolysin showed stronger antibacterial activity towards E. coli W3110, E. coli JM109(DE3) and Pseudomonas aeruginosa PAO1 than chicken egg white lysozymes. The antibacterial activity of the endolysin towards these three bacterial strains was marked when EDTA was added to the endolysin solution.     

Occurrence of Salmonella spp. in imported eggs into Albania.

Seventy-nine shell egg lots imported into Albania during the 2-years period 1996-1997 (69 lots during 1996 and 10 lots during 1997) were investigated for the presence of the Salmonella spp. Salmonella was detected in 1 out of 79 analysed pooled samples (1.26%). The Salmonella strain was isolated only from the egg shell, but not from the liquid part. The isolated strain was biochemically identified by the API 20 E system. Following biochemical identification, it was serotyped with Salmonella monovalent sera at the Institute of Public Health, Tirana, Albania and was found belonging to the Salmonella group C. The lot in which Salmonella was detected consisted of 275000 eggs.     

High Pressure-Cooking of Chicken Meat Batters with Starch, Egg White, and Iota Carrageenan

High pressure/cooking combinations (200 MPa and 400 MPa, 70°C) of chicken gels caused the formation of less compact and aggregated microstructures, which had better binding properties and were less hard. Pressurizing caused a general decrease in color parameters. The addition of starch, egg white or iota carrageenan increased water binding of meat batters. The effect of adding starch and iota carrageenan on textural properties was similar, both causing an increase in hardness and chewiness. High pressure influenced the action of the ingredients and the extent of the effect was related to the type of ingredient and the pressure level but pressure clearly predominated over ingredient effects.     

我国抽气式转杯纺纱机发展的研讨

介绍了我国抽气式转杯纺纱机由单头、多头机到成批生产具有先进水平的转杯纺纱机的研制过程,以及抽气式转杯纺纱别于自排风式转杯纺纱机的特点,转杯内积尘、积杂率低;没有铝灰纱疵;容易实现转杯高速 化;转杯内负压稳定,并进一步提高加发展我国转杯纺纱的途径和设想。     

A STUDY OF TURKEY EGG YOLK 1. COMPOSITION AND ELECTROPHORETIC SEPARATION OF COMPONENTS1

Yolks from fresh eggs produced by Broad Breasted White turkeys were blended and analyzed. Proximate composition was determined and components were separated in 7% polyacrylamide gel. Turkey egg yolk was compared with chicken egg yolk. Turkey egg yolk contained a higher percentage of solids, fat, and protein than chicken egg yolk. When separated electrophoretically, components of chicken egg yolk migrated faster than those in turkey egg yolk. Turkey yolks could be resolved into 10 or 11 distinct components; chicken yolk, into 11 or 12 components, depending on electrophoretic technique.     

基于卷积神经网络模型的裂纹鸡蛋图像识别

目的:提高基于计算机视觉的鸡蛋裂纹检测方法的准确性和运行效率。方法:使用禽蛋模拟撞击设备得到裂纹鸡蛋,并通过鸡蛋动态图像采集设备采集不同角度裂纹鸡蛋和完好鸡蛋图像,然后以原始图像和经预处理后图像分别建立用于裂纹鸡蛋图像识别的YOLO-v5、ResNet和SuffleNet模型,并比较不同模型识别准确度以及对未经预处理图像的适应性。结果:YOLO-v5、ResNet和SuffleNet模型均可有效识别经过预处理的裂纹鸡蛋图像,其验证集准确率分别为98.8%,97.8%,99.4%。对于未经预处理的裂纹鸡蛋,ResNet模型判别准确率较低,而SuffleNet模型对其适应性较好,判别准确度超过99%。结论:在卷积神经网络模型中,SuffleNet模型适用于裂纹鸡蛋图像的识别,且采集的图像无需进行预处理。     

鸡蛋液发酵条件对蛋挞营养和风味的影响

利用乳酸乳球菌（Lactococcus lactis）、嗜热链球菌（Streptococcus thermophilus）和梅利斯丛梗孢酵母（Moniliella mellis）为发酵剂,采用单因素和正交试验设计,研究发酵剂接种量、发酵时间和发酵温度对蛋挞风味和质构的影响规律,得到最优发酵工艺条件为接种量2%、发酵温度42 ℃、发酵时间42 h,此条件下制备的蛋挞外形完整、无裂缝,蛋挞芯凝固成型、色泽亮黄,甜度适中,品质最佳。质构测定结果显示,最优条件下其硬度为87.8 g,黏附力为18.3 g,黏结性为74.3 g·mm,凝胶强度为730.6 g·mm。营养成分分析显示, 经过发酵后蛋液粗蛋白呈下降趋势,氨基酸总量、必需氨基酸和鲜味氨基酸质量分数由7.55%、3.26%和3.08%分别提高至9.13%、4.01%和5.15%,蛋液由中性（pH 7.6）转为弱酸性（pH 5.1）。利用气相色谱-质谱联用技术进行风味分析,显示发酵蛋液及其制备的风味蛋挞挥发性物质分别为24 种和46 种,未发酵蛋液及其制备的普通蛋挞挥发物质分别为15 种和31 种。发酵蛋挞特征风味成分主要为己醛、壬醛、乙偶姻、丁酰乳酸丁酯、2,5-二甲基吡嗪,呈现独特的芳香风味。本研究利用蛋液发酵手段制备蛋挞的风味与营养更加丰富,为发酵蛋制品在烘焙食品中的应用提供一定理论基础。