不同腌制添加剂对咸蛋腌制效果的影响

为了提高咸蛋品质,采用8组不同的腌制添加剂腌制咸蛋,以质量分数18%的饱和食盐水作为空白对照组,对咸蛋腌制时微生物变化情况,挥发性盐基氮含量,蛋内NaCl含量,水分含量,蛋黄油渗出率,蛋清、蛋黄质地结构及其蛋白质含量进行测定,并对咸蛋进行综合感官评定。试验结果表明,采用18%饱和食盐水,0.05%山梨酸钾和0.02%双乙酸钠腌制效果最好,蛋内和腌制液中几乎不含微生物;蛋内挥发性盐基氮含量最低,其中蛋清中为3.91mg/100g,蛋黄中为4.55mg/100g,且煮熟后无黑圈蛋等劣变蛋出现。加入添加剂,可以促进盐的渗透,降低蛋内水分含量,增加蛋黄出油率,而对质构、蛋白质等无明显影响。     

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。     

泥腌、水腌咸蛋的理化指标和滋味品质差异分析

目的 研究单个泥腌与大缸水腌加工咸蛋品质的差异。方法 在18 ℃恒温下、用25.5% (m/m)的盐水水腌和25%的盐泥泥腌咸蛋, 测定腌制过程中咸蛋含盐率、含水率、游离氨基酸、感官评价等指标, 分析泥腌、水腌咸蛋盐分渗透规律、咸蛋含盐含水与感官品质间相关性、氨基酸味道强度值与滋味品质间的关系。结果 水腌咸蛋25 d成熟, 蛋白含盐率4.99%、蛋黄含盐率1.18%, 蛋内进盐量1.87 g, 盐利用率8.68%; 泥腌蛋35 d成熟, 蛋白含盐率3.53%、蛋黄含盐率1.87%, 蛋内进盐量1.48 g, 盐利用率38.95%。咸蛋的R值(蛋白或蛋黄的含盐含水比)、Q值(蛋黄与蛋白的平衡系数)、N值(蛋白蛋黄含盐比)均与感官品质有显著相关性(P＜0.05)。结论 单个泥腌制作的咸蛋蛋白不咸、蛋黄咸鲜, 品质更好, 其盐分利用率高于水腌方式。咸蛋的R值、Q值、N值可作为评价咸蛋综合感官品质和成熟度的定量指标。     

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%。     

减压法快速腌制咸蛋及蛋黄中脂肪酸变化

将减压技术应用于咸蛋的传统盐水浸泡法中,达到了明显缩短咸蛋腌制周期的目的。通过单因素试验和正交试验分析,测定各组蛋在腌制过程中的蛋黄色度、指数、蛋清和蛋黄含盐量、咸蛋合格率以及感官评分,得到减压法腌制咸蛋的最优工艺条件是:真空度为-0.09 MPa,温度为23℃,每天维持一定真空度的时间为23.5 h。利用GC-MS技术测定鲜鸭蛋和所腌制咸蛋的蛋黄中的脂肪酸,发现两者之间脂肪酸的种类没有发生变化,相对含量有所不同,腌制后棕榈酸由7.707%上升到12.910%,亚油酸由6.166%减少到3.835%,顺式-十八烷酸由16.510%增加到31.620%。     

3种方法腌制咸蛋理化性质的对比

咸鸭蛋是我国传统再制蛋之一,优质咸蛋具有蛋清洁白不咸、蛋黄松沙出油的特点,但咸蛋加工周期长,品质不太稳定。该研究引入真空减压智能腌制设备加工咸蛋,并与泥包法和常压水淹法传统咸蛋加工方法进行对比,研究3种腌制方法对咸蛋理化性质的影响。测定腌制过程中的蛋增重、蛋黄指数、蛋黄硬化率、咸蛋的盐含量、蛋黄出油率、咸蛋质构与蛋黄风味物质。结果显示,真空减压法在12 d即可腌制出成熟的咸鸭蛋,而泥包法需要22 d,常压水腌法需要32 d。真空减压法在较短时间内就可达到与泥包法和常压水淹法腌制咸蛋的品质效果,其最终蛋黄指数、蛋黄硬化率、质构和风味物质结果均相当,达到咸蛋成熟度和质构指标以及具有特有的咸蛋风味。泥包法和常压水腌法腌制的咸蛋蛋清盐含量分别为5.32%和5.40%,口感较咸;真空减压腌制的咸鸭蛋蛋清的盐含量为4.60%,蛋黄盐含量为1.98%,达到适宜口味,整体口感最好。真空减压水腌法腌制得到的咸鸭蛋出油率(47.5%)略高于常压水腌法和泥包法(分别为46.1%和43.9%)。综上,与泥包法和常压水腌法相比,真空减压水腌法加工咸蛋可大大缩短腌制周期,且咸蛋产品的咸度适宜、出油率高,表明真空减压技术可用于咸蛋快速生产加工。     

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。     

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。     

间歇式加压技术快速腌制皮蛋工艺研究

为缩短皮蛋的生产周期,按照U10(108)均匀试验设计,采用间歇式加压技术进行腌制,利用压力控制程序调控腌制罐中的加压及卸压过程,利用高压加快腌制液中碱向蛋内渗透,低压时,蛋内压力小于蛋外环境的压力,从而加速蛋内产生的水分和H2S、NH3及CO2等气体向外逸出,有利于碱进一步向蛋内渗透,起到加快皮蛋成熟的作用。通过对皮蛋蛋清、外层蛋黄及内层蛋黄的游离碱度、蛋黄硬化率和感官等指标进行综合评分,选出最优工艺条件组合为：碱(食品级氢氧化钠)质量分数5%,高压180kPa保持40min,低压保持12min,腌制206h;用此法腌制皮蛋最多可将生产周期缩短到传统工艺的78%,可以大幅提高生产效率;各因素对皮蛋品质的影响均具有显著性(P＜0.05),影响作用按大小顺序排列为腌制时长＞低压保持时间＞高压保持时间＞碱质量分数＞高压压力,综合品质与高压值呈负相关关系,在腌制时长一定的条件下,高低压分配对皮蛋品质具有重要作用,其中低压保持时间对内层蛋黄游离碱度影响最显著。     

KCl部分替代NaCl腌制咸蛋效果的比较研究

用KCl 5%、6.5%、8.5%、12.5%不同质量分数的替代量部分替代NaCl进行咸蛋腌制,25%的饱和食盐水浸泡作为腌制对照组,通过这种混合腌制的方法可直接降低食盐的添加量,改善腌制过程中咸蛋白口感偏重的问题,以腌制出品质优良的低盐咸蛋;另外,对咸蛋中NaCl含量、蛋黄出油率、水分的相关理化指标、质地结构、色度及对微观结构影响的测定,并且对咸蛋品质进行综合感官评定。结果表明：用6.5%部分替代NaCl组较好,蛋清NaCl含量从54.4mg/g降到40.1mg/g,降幅为26.29%。感官评定的结果表明：K含量过多会有苦涩味,用KCl替代物的方式腌制的咸蛋质地结构、蛋黄松沙、出油口感上没有明显的差异性,所以用KCl部分替代法降低咸蛋Na含量是可行的。     

生姜、洋葱、丁香提取物对猪肉的保鲜效果

以蒸馏水处理的猪肉为对照,研究生姜、洋葱、丁香提取物及其等体积混合制成的混合液以及化学防腐剂2,6-二叔丁基-4-甲基苯酚对猪肉保鲜效果的影响。用体积分数95%的乙醇浸提其中的有效成分,冷却猪肉分别在各组保鲜液中浸泡4min,沥干后用聚乙烯保鲜袋密封包装,最后在4℃冰箱冷藏12d,每3d测定1次感官评分、汁液流失率、蒸煮损失率、色度值、pH值、剪切力、总挥发性盐基氮（total volatile basic nitrogen,TVB-N）含量。结果表明：洋葱、生姜和丁香提取物均能够有效延长猪肉的贮藏时间,其中,生姜、洋葱、丁香混合提取物效果最佳,猪肉感官评分最高,汁液流失率和蒸煮损失率最低,色度值最好,pH值最低,剪切力最小,TVB-N含量最小,可将猪肉的保质期延长到12d。     

麦芽提取物在发酵饮料中的应用

麦芽提取物是一种完全源自谷物的天然食品,它含有丰富的麦芽糖、果糖、葡萄糖、蛋白质、小分子肽、人体必须的氨基酸和多种维生素、矿物质,还含有具有保健功能的β-葡聚糖和生育酚。用麦芽提取物生产的麦芽汁发酵饮料营养丰富,风味浓郁、独特、醇厚。与传统麦芽汁发酵饮料生产工艺相比,生产过程不需要糖化,从而使得工艺更为简单,生产周期更短,设备投入减少,降低了成本。     

Effect of addition of commercial rosemary extracts on potent odorants in cooked beef

Solid-phase microextraction-gas chromatography-olfactometry (SPME-GCO) and aroma extract dilution analysis (AEDA) were applied to measure the effects of the addition of two commercial rosemary extracts (RE) on the potent odorants in cooked beef extracts (BE). On the basis of the results of SPME-GCO and AEDA, the addition of RE imparted sweet and floral notes to BE as a result of the addition of esters and terpenes of RE. In addition, RE suppressed the formation of odorants derived via lipid oxidation and Maillard reactions. The most potent lipid oxidation volatiles consisted of 1-octen-3-one (mushroom-like), (E)-2,4-epoxy-(E)-2-decenal (metallic), and eight different aldehydes (fatty). The Maillard reaction volatiles, necessary for typical cooked beef flavor, included compounds with meaty [2-methyl-3-furanthiol, 2-methyl-3-(methylthio)furan, 2-methyl-3-(methyldithio)furan], roasty (2-furanmethanethiol), caramel-like [4-hydroxy-2,5-dimethyl-3(2H)-furanone], baked potato-like [3-(methylthio)propanal], and spicy [3-hydroxy-4,5-dimethyl-2(5H)-furanone] attributes. The suppressive effects of RE may be caused by the action of antioxidative substances in RE alone or in combination with the pH increase in BE induced by the matrix components of RE.     

柚子皮中抗过敏活性粗提物提取工艺的研究

对柚子皮抗过敏活性成分进行提取,通过单因素试验研究乙醇浓度、提取时间、提取温度、料液比和提取次数等提取条件对提取效果的影响,并通过正交试验优化其提取工艺,确定最佳提取条件为:乙醇浓度80%,提取时间45 min,提取温度为50℃,料液比1∶30(g/mL),提取次数为2次。在此条件下进行验证试验,透明质酸酶抑制率达到22.51%。     

两性植物鞣剂的制备及其鞣制性能的研究

本文初步探讨了利用亚硫酸化和Ｍａｎｎｉｃｈ反应制备两性植物鞣剂的方法及两性鞣剂的鞣性。结果表明，两性植物鞣剂使用ｐＨ值范围广，不易被空气氧化，具有明显的缩毛孔作用。用其鞣制的植鞣猪皮软面革，柔软、丰满、有弹性、粒面效果好。     

牛肉汁致突变性的研究

在用鼠伤寒沙门氏菌(Salmonella typhimurinm)雨株TA 98研究了熬煮牛肉汁的致突变性。结果表明,牛肉汁的致突变性水平取决于熬煮的时间和浓度,而与其色度无关。     

Retention of the Enzymatic Activity and Product Properties During Spray Drying of Pineapple Stem Extract in Presence of Maltodextrin

The aim of this work was to investigate the effects of drying parameters on the retention of the enzymatic activity and on the physical properties of spray-dried pineapple stem extract. A Box and Behnken experimental design was used to investigate the effects of the processing parameters on the product properties. The parameters studied were the inlet temperature of drying gas (Tgi), the feed flow rate of the pineapple extract relative to evaporative capacity of the system (W_s?/W_max), and the concentration of maltodextrin added to the extract (MD). Significant effects of the processing parameters on the retention of the proteolytic activity of the powdered extract were observed. High processing temperatures lead to a product with a smaller moisture content, particle size, and lower agglomerating tendency. A product with insignificant losses of the proteolytic activity (≈ 10%) and low moisture content (less than 6.5%) is obtained at selected conditions.     

Examination of the Relationships Between Original,Real and Apparent Extracts,and Alcohol in Pilot Plant and Commercially Produced Beers

The historical development of equations used to relate alcohol and real extract to apparent extract and original gravity, as well as ratios between the corrected Real (RDF) and Apparent Degrees of Fermentation (ADF), were examined in light of modern polynomial and non‐linear regression techniques. Comparisons were performed using an extensive data set of 532 brews obtained from commercial and pilot fermentations with statistical error analysis of these empirical relationships. New predictions of apparent extract were calculated as a function of alcohol and real extract analogous to the Improved Tabarie's formula. In addition, attempts at improving Balling's original equation model estimating original gravity from alcohol and real extract are detailed and discussed. The statistical analyses of relationships between A_w/w (alcohol by weight) and functions of OE (Original Extract), AE (Apparent Extract) and RE (Real Extract) as well as ratios between the corrected Real and Apparent Degrees of Fermentation (RDF/ADF) are reported. It is expected that this paper will be useful for brewers to more accurately estimate A_w/w and real extract values.     

Addition of grape seed extract and bearberry to porcine diets: Influence on quality attributes of raw and cooked pork

The effect of supplementation of pig diets with grape seed extract (GSE) (100, 300, 700 mg/kg feed) and bearberry (BB) (100, 300, 700 mg/kg feed) for 56 days pre-slaughter, on the oxidative stability and quality of raw and cooked M. longissimus dorsi (LD) was examined. Susceptibility of porcine liver, kidney and heart tissue homogenates to iron-induced (1 mM FeSO₄) lipid oxidation was also investigated. In raw LD steaks, stored in modified atmosphere packs (75% O₂:25% CO₂) (MAP) for up to 16 days at 4 °C, surface lightness (CIE ‘L’ value), redness (CIE ‘a’ value), lipid stability (TBARS, mg MDA (malondialdehyde)/kg muscle) and pH were not significantly affected by supplemental GSE or BB. Similarly, the oxidative stability and sensory properties of cooked LD steaks, stored in MAP (70% N₂:30% CO₂), for up to 28 days at 4 °C, were not enhanced by dietary GSE or BB. Iron-induced lipid oxidation increased in liver, kidney and heart tissue homogenates over the 24 h storage period and susceptibility to oxidation followed the order: liver > heart > kidney. Dietary GSE or BB did not significantly reduce lipid oxidation in tissue homogenates. Potential reasons for the lack of efficacy of supplemental GSE and BB on pork quality were explored.     

酶解型天然鲍鱼提取物在"鲍鱼汁"生产中的应用

利用酶解型天然鲍鱼提取物,经合理的调配,可生产出风味天然纯正的新型调味品--鲍鱼汁.