间歇超声辅助加快咸蛋腌制速度工艺优化

为加快咸蛋腌制速率,缩短腌制周期,本实验通过测定腌制过程中咸蛋含盐率、含水率、蛋黄出油率及蛋清粘度指标的变化,探究超声波技术对咸蛋腌制的影响。通过超声波单因素试验探究超声波处理次数、超声时间、超声功率以及超声频率对超声波辅助咸蛋腌制效果的影响,后由L₉(34)正交实验对间歇超声辅助腌制咸蛋工艺进行优化,由蛋清、蛋黄含盐率以及蛋黄出油率得出最优的间歇超声辅助腌制工艺为:超声波处理3次,超声时间30 min,超声功率350 W,超声频率20 kHz,此工艺相对传统腌制工艺,蛋清含盐率6.37%,蛋黄含盐率1.58%,蛋黄出油率达到57.53%。在保证咸蛋出油率等品质上,与传统工艺相比腌制时间缩短了15~20 d,且蛋白细嫩,咸蛋黄松沙出油,蛋黄外周黑圈等优点。     

腌制条件对熟制咸鸭蛋蛋黄组织形态及组成的影响

为探索咸鸭蛋腌制条件对熟制后蛋黄组织形态及组成的影响，以期减少熟制咸鸭蛋蛋黄中的硬芯含量，通过称量法、原子火焰吸收光谱分析、凯氏定氮法、差示量热扫描分析、红外光谱分析和扫描电子显微镜观察等方法对不同腌制浓度和时间下咸蛋黄不同部位理化性质以及生熟咸蛋黄微观结构的不同进行分析。结果表明，蛋黄硬芯从鸭蛋腌制的第2周出现，随着腌制时间延长，硬芯逐渐变大，腌制完成后占蛋黄总质量的33.64%～44.80%，水分含量约为21.47%～23.49%。硬芯的Na+含量在10.66～11.47 mg/g之间。腌制完成后，蛋黄外部的游离脂肪含量约为34.79%～36.34%，与外部相比，硬芯的游离脂肪含量更低，约为17.71%～27.90%，且随着腌制液盐浓度的上升而增加。腌制后蛋黄硬芯蛋白质含量上升至30%以上，高于外部。蛋黄经加热后，硬芯部分蛋黄微粒颗粒度较小，且形成间隙较小的连续结构。盐分渗透的先后顺序导致蛋黄中不同部位在组织结构和组成成分的差异，这些差异导致了熟制后蛋黄硬芯及外部的差别，且较高的腌制时间和浓度均会加剧硬芯的形成。在15%盐浓度条件下腌制4周后，得到的成熟咸蛋黄在熟制后硬芯含量较少，...     

低盐咸蛋的腌制工艺及其品质研究

提出一种两段腌制法制备低盐咸蛋的方法,分别对两段法腌制过程中咸蛋蛋白和蛋黄的水分含量、盐分含量进行实时检测,考察腌制结束时蛋黄的出油率,并且对咸蛋品质进行综合感官评定。结果表明,先使用19%盐水再换用3.5%盐水的两段法腌制工艺,咸蛋产品中蛋白盐分含量为3.64%,比传统法腌制产品蛋白盐分含量降低51.21%,口感适宜;蛋黄含盐量为0.94%,略低于传统法腌制的1.23%;蛋黄脂质渗出率为67.73%,与传统法腌制的69.22%基本相当。该腌制工艺不仅可解决传统咸蛋蛋白盐分过高、口感过咸的问题,同时也可保证蛋黄松沙出油,从而获得高品质的低盐咸蛋。     

咸蛋清脱盐工艺响应面法优化

采用截留分子量为10 000的PS膜对咸蛋清进行超滤脱盐,利用响应面法进行优化分析,得出咸蛋清脱盐最佳工艺条件:超滤时间31 min,pH 7.7,稀释倍数12,压强0.48MPa,该条件下的脱盐率为62.63%,蛋白质损失率为5.3%。     

添加不同水平NaCl对蛋黄浆质凝胶性的影响研究

为了探究腌制过程中NaCl对蛋黄浆质凝胶品质的影响,本实验主要研究了不同NaCl腌制浓度(处理浓度0%、0.5%、1%、1.5%、2%)下蛋黄浆质凝胶的保水性、浆质凝胶质构特性、浆质色度、粒径分布、流变特性、蛋白成分、显微结构。研究结果表明,在2%浓度NaCl的作用下,蛋黄浆质凝胶保水性最好,保水性显著增加(p0.05);而在2%NaCl添加量时,浆质凝胶质构特性中硬度、咀嚼性显著下降(p0.05),弹性基本不变;流变学研究发现,NaCl作用下浆质凝胶交联程度下降,形成凝胶性能下降;蛋黄浆质在NaCl的作用下,完整的乳状液体系破坏,部分蛋白产生聚集,浆质粒径变大;浆质中脂质、蛋白呈现不规则分布,NaCl的作用对浆质蛋白肽链结构并不造成影响;结果说明,NaCl作用降低了蛋黄浆质形成凝胶品质。该研究结果可为腌制过程中蛋黄浆质变化提供理论依据。     

咸蛋黄制备过程中理化指标变化规律的研究

对鸡蛋蛋黄单独腌制,测定咸蛋黄在不同腌制条件下含盐量、水分含量、出油率、蛋黄色差的变化规律,分析其指标间的相关性,并用扫描电子显微镜观察内部结构变化。结果表明:随着腌制液浓度的提高以及腌制时间的加长,含盐量、出油率、蛋黄色差增加,水分含量下降,且各指标间存在相关性。同时,蛋黄内部因腌制使得蛋黄颗粒之间变得疏松。     

Effects of salting processes and time on the chemical composition, textural properties, and microstructure of cooked duck egg

Chemical composition, textural properties, and microstructure of cooked duck egg salted by 2 methods (coating and immersing) were determined during 4 wk of salting. As the salting time increased, moisture content increased and salt content decreased for both cooked salted egg white and yolk. Oil exudation of cooked yolk and expressible water content of cooked egg white obtained from both salting methods increased as salting proceeded (P < 0.05). After cooking, oil exudation accompanied by the solubilized pigments, especially at the outer layer of yolk, was obtained. At week 3 of salting, egg yolk from coating method had the higher egg exudation than that from immersing method. As the salting times increased, the lower hardness, springiness, gumminess, chewiness, and resilience with higher adhesiveness and cohesiveness were generally found in cooked salted egg white (P < 0.05), irrespective of salting methods. Conversely, the hardness of cooked yolk increased continuously and reached the maximum at week 2 and 2 to 3 for immersing and coating method (P < 0.05), respectively. Confocal laser scanning micrographs revealed the smaller yolk granules with more release of free lipid in salted egg after heating, compared with the fresh counterpart. As visualized by scanning electron microscope, gel of cooked salted egg white was coagulum type with larger voids. Salting methods determined oil exudation in egg yolk and texture profile of egg white gel after cooking; however, those attributes were also governed by the salting time. PRACTICAL APPLICATION: Salted duck egg can be made by 2 methods (coating and immersing) affecting the characteristic of salted egg white and yolk after cooking. Desirable cooked salted egg having the red yolk with hardness and high oil exudation could be obtained when salting was carried out for 3 and 4 wk for immersing and coating method, respectively.     

Effect of dietary supplementation of gallic acid and linoleic acid mixture or their synthetic salt on egg quality

The effect of a dietary supplementation of gallic acid and linoleic acid mixture (MGL) and their synthetic salt, sodium 2,3-dihydroxy-5-(((9E,12E)-octadeca-9,12-dienyloxy)carbonyl)phenolate (NGL), on egg quality was investigated. A total of 120 laying hens were allotted into five groups over 4 weeks of the experimental period. Birds were fed the following diets: (1) control [commercial diet (CD)], (2) 0.05% MGL (w/w, GA:LA = 1:1, equal molar ratio), (3) 0.1% MGL, (4) 0.05% NGL, (5) 0.1% NGL. The performance of the hen, the anti-oxidative potential of egg albumen and yolk, and the fatty acid composition and cholesterol content of egg yolk were measured. The TBARS value of egg yolk from hens fed 0.1% MGL and 0.05% NGL was lower than that fed control diet after storage for 14 days. The ABTS⁺ reducing activity of egg albumen was significantly improved by MGL and NGL, but only NGL had an effect on yolk (p < 0.05). The dietary supplementation of 0.05% or 0.1% MGL, and 0.05% NGL raised the PUFAs composition in egg yolk. The cholesterol content of egg yolk from hens fed control diet was higher than those fed 0.1% MGL, 0.05% or 0.1% NGL (p < 0.05). In conclusion, a diet consisting of MGL and NGL can improve the antioxidative potential of egg and the fatty acid quality of egg yolk while lowering the cholesterol level.     

脉动压力对新疆风干牛肉腌制过程传质动力参数影响

为了明确脉动压力作用下新疆风干牛肉在腌制过程中盐分传质动力学过程,以牛肉为原料,采用不同脉动压力(100、120、140、160、180 kPa)在浓度为6.5%(w/w)的盐水中对牛肉(5 cm×5 cm×20 cm)进行腌制,通过测定腌制过程中牛肉的总质量、盐分含量变化量和水分含量变化量,以期获得牛肉在不同脉动压力条件下的传质动力学数据,获得最佳的腌制条件。结果表明:脉动压力和腌制时间在牛肉腌制过程中对物质的传质变化有显著影响(p<0.05)。牛肉总质量和盐分含量变化量均随脉动压力增加而增加(p<0.05);水分含量变化量在100 kPa时随着腌制时间延长而减少,其他压力条件下表现为增加;NaCl扩散速率(De)随着压力增加而增加;不同压力条件下,随着腌制时间的延长,牛肉的持水力逐渐降低,硬度逐渐增加;腌制结束后,牛肉肌原纤维蛋白都有不同程度的降解,且随着脉动压力的增加,降解程度增加。本研究明确了脉动压力对腌制风干牛肉盐分的传质规律,为风干牛肉工业化生产提供理论基础。     

脉动压技术腌制鸡蛋工艺优化

为提高咸蛋的腌制速率和食用品质,应用脉动压技术,选取高压幅值、高压与常压时间比为影响因素,通过单因素及正交试验,考察咸蛋腌制中蛋增重率、蛋清含盐量和蛋黄含盐量的变化,对脉动压腌制禽蛋工艺进行优化。结果表明：用饱和食盐溶液腌制48h,传质速率最佳的工艺为高压幅值135kPa、高压与常压时间比7.5min/15min。并对咸蛋品质进行感官评定,最终以高压幅值120kPa、高压与常压时间比为7.5min/15min 所腌制的咸蛋品质最佳。     

Physical properties and microstructure of pidan yolk as affected by different divalent and monovalent cations

Changes in physical property and microstructure of pidan yolk were monitored during pickling in the presence of different divalent (CaCl₂, MgCl₂) and monovalent (KCl) cations at different levels (2 and 5 g kg⁻¹) up to 3 weeks, followed by ageing for another 3 weeks. Pidan prepared following the commercial process, in which PbO₂ or ZnCl₂ at a level of 2 g kg⁻¹ was incorporated, was also tested. Hardness, hardening ratio, NaCl content and pH of yolk gradually increased, whereas moisture content, cohesiveness and adhesiveness decreased as the pickling/ageing time increased up to 6 weeks, regardless of cations used. During pickling/ageing, L* and b* values of interior yolk and a* of exterior yolk decreased, while L* and b* values of exterior yolk and a* value of interior yolk increased (P < 0.05). Yolk of pidan treated with PbO₂ at a level of 2 g kg⁻¹ was semisolid with lower hardening ratio, hardness, cohesiveness and adhesiveness, compared with those from other treatments. Those treated with ZnCl₂ or CaCl₂ at a level of 2 g kg⁻¹ yielded higher hardening ratio, hardness and cohesiveness but lower adhesiveness than others. Confocal laser scanning microscope indicated that the greater dehydration and release of lipids took place in pidan yolk during pickling/ageing of 6 weeks.     

Physicochemical Properties of Salted Pickled Yolks from Duck and Chicken Eggs

Duck egg yolk pickled by salt attained more desirable characteristics, such as orange color, oil exudate, and grittiness, than salted chicken egg yolk. Salted duck egg yolk reached a hardening ratio of 90% in 28-days; 35 days were required for the salted chicken egg yolk to achieve the same hardening. Moisture content of egg yolk affected the quantity of extracted lipid, an index of oil exudation. The moisture content of duck egg yolk was 19%, and the extracted lipid was 30%. But less than 4% lipid was extracted when moisture content was >27.5%. Under scanning electron microscopy, yolk spheres dominated the yolk structure probably responsible for the gritty texture.     

腌制对鸭蛋中油脂品质的影响

以新鲜鸭蛋为原料,采用裹蛋腌制法制备咸鸭蛋。研究了腌制过程中不同腌制时间对咸鸭蛋的蛋黄指数、水分含量,以及对蛋黄油皂化值、酸值、胆固醇含量、脂肪酸构成等指标的影响。研究结果表明,随着腌制时间的延长,鸭蛋中的水分含量逐渐降低,而蛋黄指数、蛋黄油皂化值、酸值、胆固醇含量逐渐增加。腌制后的鸭蛋中不饱和脂肪酸含量略有降低,而饱和脂肪酸和反式脂肪酸含量略有增加。总体而言,腌制并没有鸭蛋中蛋黄油的食用品质产生严重的影响。     

腌制方法对鸭蛋黄成分变化及品质影响

研究了鸭蛋在草木灰包裹法和盐水浸泡法腌制过程中,水分含量、盐分含量、R值与Q值,蛋黄总脂肪、可溶性蛋白质和巯基含量的变化以及成熟(7周)后两者蛋黄的感官品质。7周内,随腌制时间的延长,浸泡法鸭蛋黄水分含量明显低于包裹法鸭蛋黄,盐分含量却高于包裹法;蛋清R值高于蛋黄,灰蛋的R值、Q值都低于盐水蛋。第7周,灰蛋和盐水蛋的Q值上升为0.88和0.90;脂肪占湿重的含量上升至48.45%和50.67%,而腌制期总脂肪量是没有变化的;可溶性蛋白质含量增加至6.75%和6.08%;表面巯基和游离巯基下降至0.31、0.28mmol/g蛋黄和1.68、1.34mmol/g蛋黄。灰蛋蛋黄在形态、滋味和气味方面明显优于盐水蛋,感官评分分别为88.9和78.65。     

咸蛋腌制添加抗氧化剂改善蛋黄的内质特性

为解决实际生产中咸蛋黄硬心、黑圈的问题,将三种天然抗氧化剂应用于咸蛋包泥腌制工艺中,比较其对咸蛋内质理化指标的影响。试验结果表明:料泥中添加茶多酚、虾青素、酵母硒不改变咸蛋成熟期(19 d),可显著减小蛋黄硬心质量比(5.75%、6.68%、9.06%,对照15.32%)和抑制黑圈生成(1%～6%、2%～5%、8%～15%,对照18%～41%)、且黑圈颜色浅,呈现浅灰色;蛋黄的硬度、弹性、咀嚼性显著降低。茶多酚与虾青素组较对照组可分别降低脂质初级氧化产物共轭二烯酸比率37.50%和31.25%,次级氧化产物丙二醛含量分别减少23.31%和41.56%(p0.05),酵母硒影响不显著(p0.05)。蛋黄的游离脂肪酸种类基本不变,相对含量略有变化:茶多酚组和虾青素组的不饱和脂肪酸总量、油酸、亚油酸含量较对照组显著增大,酵母硒组与对照组差异不显著。综合来看,蛋黄感官品质较对照组大幅提升,蛋黄色泽呈现橙红色,蛋黄脂质氧化分解程度减轻。鉴于茶多酚原来成本更低,茶多酚最适用于盐浸泥涂包法快速生产咸蛋。     

Effect of salting processes on chemical composition,textural properties and microstructure of duck egg

BACKGROUND: Salted eggs have been produced in Thailand and consumed nationwide. Salted egg can be made by brining eggs in saturated saline or by coating the egg with soil paste mixed with salt. The achievement of salting is generally indicated by the textural development of egg yolk. Yolk property is therefore a prime factor governing consumer acceptability and market demand. The objective of this study was to determine chemical composition, textural properties and microstructure of duck egg obtained from the coating and immersing methods at different salting times. RESULTS: Decreases in moisture content with coincidental increases in salt content in both egg white and yolk were observed during salting, regardless of salting process. However, no difference in salt content was noticeable in yolks (P > 0.05). The paste coating method tended to yield greater oil exudation of egg yolk than the immersing method. Maximum transition temperature (T_max) of egg proteins and thiobarbituric acid‐reactive substance (TBARS) value in yolk increased with increasing salting time. A similar hardening ratio of yolk was observed in both processes. Higher hardness and adhesiveness were found in yolk with the paste coating method, whereas greater fracturability, springiness, gumminess and chewiness were observed with the immersing method. Nevertheless, both processes rendered the yolk with similar cohesiveness. Yolk granules were aligned closely when salting proceeded, irrespective of salting process. CONCLUSION: Dehydration and release of lipids in egg yolk increased with increasing salting time and were more pronounced with the paste coating method. Therefore salting processes affected the properties of salted eggs. Copyright © 2009 Society of Chemical Industry     

A mathematical model of inactivation kinetics for a four-strain composite of Salmonella Enteritidis and Oranienburg in commercial liquid egg yolk

The goal of this study was to develop a general model of inactivation of salmonellae in commercial liquid egg yolk for temperatures ranging from 58 °C to 66 °C by studying the inactivation kinetics of Salmonella in liquid egg yolk. Heat-resistant salmonellae (three serovars of Enteritidis [two of phage type 8 and one PT 13] and one Oranienburg) were grown to stationary phase in Tryptic Soy Broth and concentrated 10-fold by centrifugation. Each inoculum was added to liquid egg yolk and mixed thoroughly, resulting in a final population of ca. 7 log CFU/ml egg yolk. Inoculated yolk was injected into sterile glass capillary tubes, flame-sealed and heated in a water bath at 58, 60, 62, 64, and 66 °C. Capillary tubes were ethanol sanitized, rinsed, and contents were extracted. Yolk was diluted, surface plated onto Tryptic Soy Agar + 0.1% sodium pyruvate and 50 μg/ml nalidixic acid and incubated at 37 °C for 24 h before colonies were enumerated. Decimal reduction values were calculated from survivor curves with a minimum inactivation of 6 log CFU/ml at each temperature. Survival curves (except for 66 °C) featured initial lag periods before first order linear inactivation. Estimated asymptotic D-values were 1.83 min at 58 °C, 0.69 min at 60 °C, 0.26 min at 62 °C, 0.096 min at 64 °C and 0.036 min at 66 °C. The estimate of the asymptotic z-value was ca. 4.7 °C with standard error of 0.07 °C. A linear relationship between the log₁₀ of the lag times and temperature was observed. A general kinetic model of inactivation was developed. The results of the study provide information that can be used by processors to aid in producing safe pasteurized egg yolk products and for satisfying pasteurization performance standards and developing industry guidance.     

超声波辅助咸蛋快速腌制方法

对比传统腌制、酸碱处理、超声波处理3种腌制方法;研究超声波处理及未处理腌制期间蛋内盐度分布规律并比较成熟时间。结果表明:超声波预处理腌制的蛋内部盐度分布均匀,咸度适中,蛋清和蛋黄的色泽、质地及蛋黄出油率均优于其他两种方法;采用超声波处理的蛋,在腌制末期,咸蛋内部含盐量平均分布,而未处理的咸蛋内部盐含量由外到内逐渐减小;经超声波预处理的咸蛋成熟时间为27 d,比未处理的提前了13 d,腌制周期缩短33%。     

Study on kinetics of mass transfer in water-boiled salted duck during wet-curing

Curing is the most important process for the production of water-boiled salted duck. This work was designed to compare the difference in mass transfer of water and salt in water-boiled salted duck among different concentration brines during wet-curing. Duck breasts were wet-cured for 72 h in four brine solutions having concentrations, i.e. 5%, 15%, and 25% NaCl (w/w), and repeatedly reused supersaturated brine (?25% NaCl (w/w)) which is often used in commercial production in China. Results showed that as brine concentration increased, the weight gain and water content decreased and the NaCl content of meat samples increased. Moreover, hardness and springiness increased with increasing brine concentration coupled with a drop in water holding capacity (WHC). Higher salt concentration brines showed a higher proteolysis than lower salt concentration brines. Therefore, 15% NaCl (w/w) brine, the solution having moderate salt concentration, was the most suitable for wet-curing just because of its higher process yields, effective diffusivity value, D_e, and lower health risks.     

Use of sodium nitrite in salt-curing of Atlantic salmon (Salmo salar L.) – Impact on product quality

Quality changes during processing and quality differences in smoked fillets of Atlantic salmon (4–5 kg) salted with nitrite salt compared to table salted fillets were measured. Quality parameters from right-side fillets dry salted with nitrite salt were compared with the respective left-side fillets treated the same way with table salt. Ten raw right-side fillets were analysed and used as raw material reference. Use of nitrite salt in salt-curing of smoked salmon affected colour to a more reddish hue, tended to increase carotenoid stability and displayed positive effects on NaCl diffusivity. Only slight weight changes and change in texture properties were revealed. The use of nitrite salt displayed no adverse effects like increased content of N-nitrosoamines in smoked products. In fact, significant lower contents of N-nitrosoamines were found in nitrite salted smoked fillets compared to smoked fillets salted with table salt. Relatively high amounts of residual nitrite in nitrite-treated fillets seem to be the most prominent adverse effect caused by the use of nitrite salt in salt-curing of smoked Atlantic salmon.