不同浓度盐水对鸭肉湿腌时传质动力的影响

研究采用盐水鸭生产时使用的过饱和盐水——老卤和其他三种不同浓度的盐水(5%、15%和25%NaCl,w/w)对鸭腿肉按照盐水鸭的生产过程进行腌制,通过对腌制过程中鸭腿肉的食盐、水分和总重变化进行测定,以期获得不同盐水浓度下鸭肉的传质动力学数据,并获得腌制最适盐水浓度。结果表明,盐水浓度显著影响鸭腿肉在腌制过程中的传质变化。鸭腿肉的重量变化、水分获得都是随着盐水溶液浓度的降低而增加,盐分变化则相反。中等浓度的盐水溶液(15%NaCl,w/w)腌制的鸭肉产量较高,有较高的扩散速率——De值,对人体的损害较小。因此,较为适于用来腌制鸭肉。另外,腌制的预测模型和扩散公式计算得到的数据都有良好的线性关系,可以很好地适用于鸭腿肉的腌制实验研究。      

不同浓度盐水对鸭肉湿腌时传质动力的影响

研究采用盐水鸭生产时使用的过饱和盐水——老卤和其他三种不同浓度的盐水(5%、15%和25%NaCl,w/w)对鸭腿肉按照盐水鸭的生产过程进行腌制,通过对腌制过程中鸭腿肉的食盐、水分和总重变化进行测定,以期获得不同盐水浓度下鸭肉的传质动力学数据,并获得腌制最适盐水浓度。结果表明,盐水浓度显著影响鸭腿肉在腌制过程中的传质变化。鸭腿肉的重量变化、水分获得都是随着盐水溶液浓度的降低而增加,盐分变化则相反。中等浓度的盐水溶液(15%NaCl,w/w)腌制的鸭肉产量较高,有较高的扩散速率——De值,对人体的损害较小。因此,较为适于用来腌制鸭肉。另外,腌制的预测模型和扩散公式计算得到的数据都有良好的线性关系,可以很好地适用于鸭腿肉的腌制实验研究。     

腌制条件对兔肉湿腌传质动力的影响

以新鲜兔肉为原料,分析不同盐水浓度(6%,10%,15%)、腌制温度(4,15,25℃)及搅拌对兔肉湿腌传质动力学的影响。结果表明:不同条件腌制兔肉的ΔM~w_t、ΔM~(NaCl)_t和ΔM~0_t与t~(0.5)之间具有良好的相关性,k_2受盐水浓度、温度及搅拌影响。不同盐水浓度条件下,盐水浓度10%,De值最大为1.18×10~(-9) m~2/s;不同温度条件下,15℃腌制兔肉的De值最大,为5.86×10~(-9) m~2/s;25℃搅拌腌制使兔肉的De值增大,但4℃和15℃搅拌腌制使兔肉的D_e值有所减小。故盐水浓度10%、适宜温度(15℃)的兔肉加搅拌腌制的扩散速率较大。     

不同腌制条件对草鱼湿腌传质动力的影响

研究盐水浓度(5%、10%、15%)、料液比(1∶2、1∶3、1∶4)、腌制温度(5、10、20℃)三个因素对草鱼湿腌传质动力的影响。通过对腌制过程中鱼肉中的盐分、水分和重量变化进行测定,来获得不同腌制条件下,草鱼腌制的传质动力学数据。结果表明:盐水浓度对草鱼腌制影响极显著(p0.01),料液比在腌制后期对草鱼腌制影响显著(p0.05),温度对草鱼腌制影响显著(p0.05)。盐水浓度单因素中15%的有效扩散速率De值最大;料液比单因素中1∶2的De值最大;温度单因素中10℃的De值较大。此外,草鱼湿腌的盐分预测模型和扩散公式计算得到的数据都有良好的线性关系,经验证,实验值与理论值误差较小,可以准确地预测鱼肉中盐分含量。     

不同腌制条件对草鱼湿腌传质动力的影响

研究盐水浓度(5%、10%、15%)、料液比(1∶2、1∶3、1∶4)、腌制温度(5、10、20℃)三个因素对草鱼湿腌传质动力的影响。通过对腌制过程中鱼肉中的盐分、水分和重量变化进行测定,来获得不同腌制条件下,草鱼腌制的传质动力学数据。结果表明:盐水浓度对草鱼腌制影响极显著(p<0.01),料液比在腌制后期对草鱼腌制影响显著(p<0.05),温度对草鱼腌制影响显著(p<0.05)。盐水浓度单因素中15%的有效扩散速率De值最大;料液比单因素中1∶2的De值最大;温度单因素中10℃的De值较大。此外,草鱼湿腌的盐分预测模型和扩散公式计算得到的数据都有良好的线性关系,经验证,实验值与理论值误差较小,可以准确地预测鱼肉中盐分含量。      

复合添加物在腌制过程中对兔肉传质动力学和肌原纤维蛋白的影响

以兔肉为原料,研究5种不同复合添加物(食盐为对照组、"食盐+亚硝酸钠"记为Y组、"食盐+亚硝酸钠+香辛料"记为YY组、"食盐+亚硝酸钠+香辛料+磷酸盐"记为YL组、"食盐+亚硝酸钠+香辛料+磷酸盐+调味料"记为YW组)在腌制过程中对兔肉传质动力学和肌原纤维蛋白的影响。结果表明:复合添加物对兔肉水分变化量、食盐变化量、总重变化量(△M_t~w、△M_t~(NaCl)、△M_t~0)有一定影响,但差异不显著(P0.05);复合添加物降低了腌制兔肉的De值,且Y组De值最小,为9.63×10~(-10) m~2/s;复合添加物不同程度改变了腌制兔肉的持水力和硬度,相比对照组,YL、YW组的持水力显著增加(P0.05)、硬度显著降低(P0.05),Y、YY组的持水力没有显著变化(P0.05)、但硬度变化明显(P0.05);复合添加物降低了肌原纤维蛋白储能模量(G')(P0.05),且与对照组相比,Y、YY组肌球蛋白变性温度提高,Y、YL和YW组肌动蛋白变性温度降低;SDS-PAGE电泳分析表明,复合添加物促进肌原纤维蛋白不同程度降解,且YL组的降解程度最大。     

牛肉在湿腌过程中亚硝酸盐的变化

本课题主要研究牛肉在不同温度下的湿腌过程中亚酸盐的变化规律,为低亚硝肉制品的开发起基础性研究的作用.     

木瓜蛋白酶对鸡肉湿腌过程中传质动力学的影响

以新鲜鸡肉为实验对象,分析不同木瓜蛋白酶添加量(占腌制液质量0%、0. 06%、0. 12%、0. 18%、0. 24%)对鸡肉湿腌过程中传质动力学、硬度以及压榨损失的影响。研究表明:添加木瓜蛋白酶对鸡肉湿腌过程中的传质动力学参数具有显著影响,随着腌制液中酶浓度的增加,鸡肉的水分变化ΔM_t~w、盐分变化ΔM_t~(NaCl)以及总重变化ΔM_t~o不断增加,腌制9 h内水分盐分快速渗透;硬度降低;压榨损失随着腌制时间的延长有一定降低;腌制过程中鸡肉的ΔM_t~w、ΔM_t~(NaCl)、ΔM_t~o值与腌制时间t0. 5具有很好的相关性(R~2≥0. 902),较好的适用于本研究;酶浓度0. 18%与0. 24%时鸡肉腌制有效扩散系数De最大(1. 02×10~(-9));表明腌制液中添加木瓜蛋白酶可以有效提高肉制品腌制速率。     

草鱼低温循环腌制过程中的传质动力学研究

通过测定草鱼腌制过程中的NaCl含量、水分含量、持水力、传质系数及质构等相关指标来研究草鱼低温循环腌制过程的传质动力学。结果表明,低温循环腌制的腌制速度明显大于静置低温腌制速度,且随着循环流量增加,腌制速度呈上升趋势,当循环流量达到一定程度,腌制速度将趋于平衡。临界循环流量为1 100 mL/min,此参数可为其工业应用提供参考。综合评价,循环腌制的含水量、持水力与质构指标均优于静置腌制,以中速(1 100 mL/min)效果最佳,传质系数为1.61×10~(-9)m~2/s。     

猪肉腌制过程中的传质动力学研究

采用5 种不同质量分数的食盐水（5%、10%、15%、20%和25%）对猪肉块（1 cm×1 cm×1 cm）进行腌制,通过测定腌制过程中猪肉的总质量、食盐和水分变化,以及通过差示扫描量热仪（differential scanningcalorimeter,DSC）观察肌肉蛋白变性情况,以期获得猪肉在不同浓度腌制液中的传质动力学数据,获得最适腌制条件。结果表明：盐水质量分数和腌制时间均显著影响了猪肉在腌制过程中物质的传质变化。猪肉总质量、水分含量均随盐水质量分数增加而减少,而NaCl变化则相反,且在腌制前1 h内各变化量较明显,之后趋于平缓。在15%的腌制液中猪肉产量较高,且NaCl扩散速率（De）快,因此较适用于猪肉腌制。另外,猪肉在腌制过程中各物质传质随时间变化的预测模型具有良好的线性相关,可以很好地适用于本研究。     

Mass transfer dynamics during high pressure brining of chicken breast

The objectives of this study were to investigate the changes in mass transfer, textural properties and water holding capacity of chicken breast when brine treated under different pressures. Chicken breasts were treated for up to 20 min in 4% sodium chloride solution under five pressures: 50, 100, 150, 200, and 300 MPa at 25 ± 1 °C. The results indicated that the total weight and water uptake of the chicken breast increased with increasing pressure up to 150 MPa, and then decreased with further pressure increase up to 300 MPa. Chicken breast samples brined at 150 MPa, with a sodium chloride effective diffusivity value of 2.96 × 10⁻⁸ m²/s, exhibited minimum hardness and maximum water holding capacity. In general, pressure treatment at 150 MPa was found to be the most suitable level for curing based on its higher yield, effective diffusivity and improved texture and water holding capacity.     

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.     

反复冻融对兔肉腌制过程中的传质动力影响

以新鲜兔肉为对照,分析反复冻融(0、1、2、3次)原料肉在湿腌过程中的传质动力学、流变特性和蛋白质SDS-PAGE变化。结果表明:反复冻融兔肉腌制4h内的水分变化(ΔM_t~w)、盐分变化(ΔM_t~(Nacl))和总重变化(ΔM_t~0)快速增加,但冻融3次兔肉腌制前3 h有失水现象;冻融次数越多,兔肉腌制过程中的ΔM_t~0和ΔM_t~(Nacl)值越大,而ΔMwt值越小;反复冻融兔肉的ΔM_t~w、ΔM_t~(Nacl)和ΔM_t~0值与t~0.5具有很好的相关性(R2≥0.901 1),冻融1次兔肉腌制过程中的表观扩散系数(D_e)值最大(5.46×10-9m~2/s)。与新鲜兔肉比较,反复冻融兔肉腌制24 h的肌原纤维蛋白G'较低,且肌球蛋白和肌动蛋白变性温度随冻融次数的增加而升高;兔肉腌制4、24和48 h的肌原纤维蛋白条带不同程度变浅,且冻融3次腌制兔肉的肌原纤维蛋白条带逐渐变淡、变少,表明蛋白质降解加剧。     

Mass transfer dynamics during the acidic marination of turkey meat

The mass transfers of water, acid and NaCl in turkey meat cubes (initial volume 1 cm³ during marination were evaluated at various molalities of acetic acid (0.0-1.0) and NaCl (0.0-1.5). An experimental design was drawn up, associated with an estimate of the velocities of each component by means of kinetic monitoring. High mass yields (mass gain >0.3 kg kg⁻¹), obtained for the marinades most dilute in acid, were found only in the absence of NaCl. The presence of NaCl had a negative effect on mass yield, counterbalanced by the positive effect of acetic acid. In the case of acidic marinades with low salt concentration, high solute flux densities were observed upon the start of immersion, as well as solute transfer velocities greater than those in water. This phenomenon may be explained by the superimposition of material diffusion and transport phenomena caused by a fall in internal filtration pressure due to expansion of the protein matrix. The fall in the buffering capacity of the meat in the course of soaking, related to the leakage of proteins, dipeptides and lactates, may explain the low pH values obtained during immersion in comparison with theoretical data.     

Mass transfer during osmotic dehydration of pineapple rings

The effect of temperature (30, 40 and 50°C) and sucrose concentration (50, 60 and 70°Brix) on the osmotic dehydration of commercial size pineapple rings were studied, at an initial ratio of 1:4 fruit:sucrose solution. The rate of water loss in the fruit varied with both osmotic solution concentration and temperature. A proposed model based on Crank's equation was fitted to the experimental data.     

Mass transfer during infrared drying of cashew kernel

Mass transfer during infrared drying of cashew kernel has been studied considering unsteady state diffusion. The effective diffusion coefficients were estimated over a range of temperatures (100–120°C), considering the cashew kernel as an arbitrary configuration. The dependence of effective diffusion coefficient on temperature was explained based on Arrhenius equation. The activation energy of the infrared drying of cashew kernel was found to be 28.7 kJ/mol.