卡拉胶和黄原胶对转谷氨酰胺酶处理PSE兔肉糜蒸煮损失与成胶能力的影响

通过添加卡拉胶和黄原胶以及转谷氨酰胺酶（transglutaminase,TG）处理,改进PSE兔肉糜的持水力和热诱导凝胶性质。以正常兔肉为对照,分别研究不同质量分数卡拉胶和黄原胶对TG处理PSE（肉色苍白、柔软、汁液渗出）兔肉糜蒸煮损失、热诱导凝胶强度以及色泽的影响。结果表明：添加质量分数为0～0.8%的卡拉胶对0.3%TG处理PSE和正常兔肉糜热诱导凝胶强度的提高作用没有显著影响,而蒸煮损失随卡拉胶质量分数的增加显著下降,L*值和a*值均明显下降;随着黄原胶质量分数的增加,PSE和正常兔肉的蒸煮损失显著减少,但凝胶强度均呈下降趋势,L*值和a*值均明显下降。在0.3%TG处理肉糜中分别添加质量分数为0.8%的卡拉胶或质量分数为0.05%～0.10%的黄原胶可显著降低蒸煮损失,并获得较好的凝胶效果。     

鸡肉类PSE肉与正常肉流变、质构特性的比较

以亮度值(L*)与屠宰24h后的pH值(pH24h)作为区分类PSE肉与正常鸡肉的指标,对两者肉糜的流变特性、质构特性和蒸煮损失进行研究。结果表明:具有低pH24h、高L*值的类PSE肉,在流变性、蒸煮损失和质构上存在显著差异。类PSE肉的流变曲线趋势异于正常肉,表现出低的贮能模量和大相位角正切值(P<0.05),极值所对应的温度低于正常肉(P<0.05);类PSE的蒸煮损失高于正常肉(P<0.05),硬度、弹性、黏聚性、咀嚼性和回弹力显著低于正常肉。鸡胸肉的pH值和L*值与其肉糜的质构与流变特性密切相关,是分析和控制类PSE对深加工产品影响的重要参考因素。     

卡拉胶、转谷氨酰胺酶及大豆分离蛋白对猪PSE肉低温香肠保水性和感官品质的影响

为研究卡拉胶、转谷氨酰胺酶（transglutaminase,TG）及大豆分离蛋白对猪PSE（pale、soft、exudative）肉低温香肠保水性和感官品质的影响,通过单因素试验和L9（34）正交试验,以蒸煮损失和感官品质为参考指标,确定最适添加量。结果表明：单独添加卡拉胶或大豆分离蛋白可以明显改善猪PSE肉低温香肠的蒸煮损失（P＜0.05）,TG添加量超过0.6%会导致猪PSE肉低温香肠的保水性发生显著下降（P＜0.05）;正交试验进一步优化后确定卡拉胶、TG及大豆分离蛋白的最适添加量分别为0.5%、0.2%和4%;通过优选后的正交工艺进行验证发现,该工艺对猪PSE肉低温香肠的保水性和感官品质有明显的改善作用。     

黄原胶对艾草猪肉香肠凝胶品质的影响

以艾草添加量1.5%的猪肉香肠作为研究对象,考察黄原胶质量分数(0～0.8%)对艾草香肠凝胶品质的影响。结果显示,当黄原胶质量分数大于0.2%时,艾草猪肉香肠凝胶蒸煮损失值显著降低(P<0.05);当黄原胶质量分数大于0.4%时,b*值和咀嚼性显著减小(P<0.05);当黄原胶质量分数为0.8%时,艾草猪肉香肠凝胶的保水性值显著增大(P<0.05),硬度和咀嚼性均显著减小(P<0.05)。     

转谷氨酰胺酶对猪肉肌原纤维蛋白凝胶性质的影响

以猪背最长肌为材料,研究转谷氨酰胺酶(TG)浓度对肌原纤维蛋白质(MP)热诱导凝胶强度和持水力的影响,探讨转谷氨酰胺酶在不同pH 值条件下对肌原纤维蛋白质凝聚性和交联的作用以及对热诱导凝胶强度、持水力的影响,比较TG 处理对凝胶结构的微观影响。结果表明：TG 处理会显著提高肌原纤维蛋白质的凝胶强度,TG最佳使用量为0.3%,NaCl 浓度为0.6mol/L,pH 值在5.8～6.4 之间时添加TG 会增加蛋白质的蒸煮损失,而pH 值在6.4～6.7 范围内添加TG 可降低蒸煮损失;电镜扫描结果表明TG 处理可改善热诱导凝胶的网络结构;TG 处理可改善肌原纤维蛋白的质构性质。     

磷酸盐对PSE 猪肉肌原纤维蛋白溶胶及凝胶性质的影响

PSE 肉的肌原纤维蛋白质(MP)的溶解度比正常肉(red, firm and non-exudative;RFN)低、凝胶性质比RFN差,本研究探讨磷酸盐对PSE 猪肉凝胶特性的影响。以猪背最长肌PSE 和RFN 肉为材料,采用分光光度法、质构测定法等研究六偏磷酸钠(SHMP)、焦磷酸钠(SPP)、三聚磷酸钠(TPP)对MP 溶解特性、聚集性以及凝胶强度的影响。结果表明,磷酸盐对PSE 和RFN 提取MP 的溶解度、蛋白质聚集性和凝胶强度均有显著的影响,TPP 添加量为0.25% 时PSE 的凝胶强度接近未添加TPP 的RFN 的凝胶强度。磷酸盐可改善体系环境,改善PSE 蛋白质溶胶及凝胶的功能特性。     

菊粉取代玉米磷酸酯双淀粉对香肠质构和感官特性的影响

本文以鸡肉和猪肉为原料,在香肠的生产过程中用短链菊粉按照0%(对照组)、10%、30%、50%、70%、100%的比例取代玉米磷酸酯双淀粉,探索对香肠品质的影响。试验采用质构仪和色差计分别测定香肠的质构特性和色泽,同时进行感官评价,并计算蒸煮损失。结果表明:菊粉取代玉米磷酸酯双淀粉后,各组香肠的弹性与对照组差异不显著(p0.05),而硬度和咀嚼性显著降低(p0.05),香肠口感评分值提高;含菊粉香肠的红色值(a*)、黄色值(b*)降低,除取代比为70%的香肠亮度增加外,其它各组香肠的亮度差异不显著(p0.05);菊粉的添加降低了香肠的蒸煮损失,说明香肠的出品率得到提高。综合各项分析,当菊粉取代玉米磷酸酯双淀粉的比例为70%时,香肠的评分值最高且品质有显著提高。     

海藻酸钠-钙凝胶特性及其在低脂猪肉糜中应用的研究

海藻酸钠-钙凝胶具有良好凝胶强度且热不可逆,可改善肉糜、香肠类产品的质构及持水性。实验以凝胶强度为指标,采用不同种类的海藻酸钠,碳酸钙作为钙源,葡萄糖酸内酯(GDL)控制钙离子的释放,优化配比,并将其用于猪肉糜,研究其对肉糜蒸煮损失、冻融损失和质构性质的影响。结果表明,粘度为800cps的高古罗糖醛酸型海藻酸钠凝胶效果最好,最佳配比(重量)为:55.6%海藻酸钠,13.9%碳酸钙,30.6%葡萄糖酸内酯。将以上比例的添加剂添加到低脂猪肉糜中,结果显示在总添加剂量为原料重量(低脂猪肉)1.0%～1.5%时,肉糜在质构性质、蒸煮损失和冻融损失方面有较好的改进效果。     

复合无磷保水剂对PSE猪肉低温香肠贮藏期间品质变化的影响

将L-精氨酸、碳酸钠和柠檬酸钠3种无磷保水剂进行复配,添加至PSE（pale, soft, exudative）猪肉中制备低温香肠,作为处理组,以不添加保水剂的正常猪肉及PSE猪肉所制的低温香肠作为对照组。通过测定贮藏期间3组香肠的pH值、水分含量、硫代巴比妥酸反应物（thiobarbituric acid reactive substances,TBARs）值、菌落总数及质构指标,并对其进行感官评价,探索复配无磷保水剂对贮藏期间PSE猪肉低温香肠品质的影响。结果表明：随着贮藏时间的延长,各组香肠的pH值、水分含量、硬度、弹性、内聚性、咀嚼性及感官评分均呈下降趋势,但TBARs值与内聚性变化不显著;贮藏后期处理组香肠pH值（5.41）、水分含量（49.15%）、硬度（6656.89 g）、弹性（0.78 mm）和咀嚼性（1207.44 g）均显著高于PSE猪肉组（pH 5.24、水分含量45.33%、硬度6034.67g、弹性0.69 mm、咀嚼性1004.41g）;贮藏42 d处理组香肠菌落总数为4.66（lg（CFU/g））,显著低于PSE猪肉组（5.89（lg（CFU/g）））,且与正常猪肉组相似。说明复合无磷保水剂可改善PSE猪肉低温香肠品质,提高PSE猪肉的加工利用率。     

屠宰季节对不同品种生猪宰前应激及宰后肉品质的影响

通过分析血液应激指标、胴体pH值和温度、胴体表面损伤、预冷损耗、色泽、滴水损失、蒸煮损失、剪切力、质构特性及PSE肉(pale,soft and exudative meat)发生率等指标,探究春、夏、秋、冬4个季节宰杀对杜长大三元杂交猪和三门峡黑猪宰前应激及宰后猪肉品质的影响。结果表明:与夏、冬2季相比,春、秋季宰杀三门峡黑猪和杜长大三元杂交猪血液中的丙氨酸氨基转移酶(alanine aminotransferase,ALT)、肌酸激酶(creatine kinase,CK)、皮质醇(cortisol,COR)、乳酸脱氢酶(lactate dehydrogenase,LDH)、肌酐(creatinine,CRE)和促肾上腺素皮质激素(adrenocorticotropic hormone,ACTH)含量均较低;春季宰杀杜长大三元杂交猪和三门峡黑猪血液中的葡萄糖(glucose,GLU)和乳酸(lactic acid,LAC)含量显著低于其他3个季节(P0.05);春季生猪宰前应激效应较低,胴体表面损伤与预冷损耗显著降低(P0.05);春、秋季宰杀冷却猪肉的色泽、保水性及嫩度较好。在同一季节,三门峡黑猪的抗应激能力优于杜长大三元杂交猪,且宰后猪肉的pH_(24h)(宰后24 h的pH值)、红度值(a~*)和咀嚼性相对较高,亮度值(L~*)、滴水损失、蒸煮损失及剪切力相对较低,PSE肉的发生率较低,说明黑猪肉的品质更好。     

Improvement of the physicochemical properties of pale soft and exudative (PSE) pork meat products with an extract from mechanically deboned turkey meat (MDTM)

Loss of protein functionality of pale soft and exudative (PSE) meat and a surplus of mechanically deboned turkey meat (MDTM) has negative economic impacts on the meat industry. The objective of this research was to add functional proteins from an extract of MDTM to PSE meat to create a value-added pork sausage product. Sausages manufactured from PSE incorporating an MDTM extract exhibited a 30% increase in rigidity (P<0.05) compared to those manufactured using brine alone. Sausages made from PSE and normal pork with the MDTM extract demonstrated little difference in water holding capacity (P>0.05), and reductions of 4.1 and 3.1% in cooking loss (P<0.05), respectively, compared to sausages made employing brine alone. Introducing functional proteins derived from MDTM to processed meat made with PSE pork has the potential to enhance the economic value to both of these low value raw materials.     

The effect of ionic strength, polyphosphates type, pH, cooking temperature and preblending on the functional properties of normal and pale, soft, exudative (PSE) pork

Compared to processed meat product made from normal pork, products made from pale soft exudative (PSE) pork have higher cook loss (CL) and weaker texture. In this study interactions between a range of processing conditions (ionic strength, polyphosphate addition, polyphosphate chain length, pH, cooking temperature and time between preparation and cooking), and their effect on the texture [shear stress (SS), true shear strain (TSS)] and CL of gels made from normal and PSE pork were examined. Of the processing conditions studied, ionic strength, polyphosphate addition and polyphosphate chain length affected the functional properties of normal and PSE pork differently. Generally, the functional properties of normal pork were superior to PSE pork, with no combination of conditions making all the functional properties of PSE pork equal to those of normal pork under the same conditions. The combination of conditions that was most effective in reducing the difference between normal and PSE pork was high ionic strength in the presence of added polyphosphate. Under these conditions there was no significant difference in CL between normal and PSE pork, although the texture (SS and TSS) of the PSE pork samples was still inferior.     

Quality characteristics of Chinese sausages made from PSE pork

Chinese sausages made from normal and different levels of PSE pork (100% Normal, 50%Normal+50% PSE and 100% PSE) were vacuum-packaged and stored at 4 °C for 45 days. The composition, processing yield, pH value, thiobarbituric acid (TBA) value, water activity, lactic acid bacteria counts and sensory properties of the meat products were evaluated. PSE pork loins had lower pH value, water holding capacity, moisture, fat and myofibrillar proteins content, but higher L^* value, drip loss and protein content than normal pork. Sausages made from 100% PSE pork had lower pH value, processing yield, moisture and fat content, but higher protein content than those of the 100% Normal and the 50% Normal+50% PSE treatments. Water activity was higher in the 100% PSE treatment than in other treatments. No differences in lactic acid bacterial counts among these treatments were observed. The pH values and water activity of the meat samples decreased, while lactic acid bacterial counts increased with storage time. TBA values among these treatments were not significantly different; however, the increase% of TBA values was higher for the 100% PSE treatment. TBA values of all treatments remained relatively low during storage. Chinese sausages made with 50–100% PSE pork had lower sensory texture, flavor and overall acceptability scores than the control samples, but were of acceptable quality.     

烟酸处理血粉在猪肉肠制作工艺的应用

将自制的烟酸处理血粉应用于猪肉香肠制作.通过单因素试验考察烟酸处理血粉添加量、VE 添加量以及煮制温度与时间对色泽的影响;在此基础上,以猪肉香肠感官品质为考察指标、通过正交试验优化加工工艺条件.单因素试验表明烟酸处理血粉添加量、煮制温度均对肉肠制品色泽影响很大,而 VE 添加量与煮制时间对肉肠制品色泽影响较小;正交试验结果表明,对肉肠制品品质影响顺序依次是烟酸处理血粉添加量、煮制温度、VE 添加量、煮制时间.烟酸处理血粉添加量0.4%,VE 添加量0.25%,煮制温度90℃,煮制时间50min,产品感官评分最高达9.33分     

Presalting effects on water retention of pork and beef batters

Presalting effects were studied by measuring cooking loss as a function of chopping time for pork and beef batters. Presalting (ground meat/salt/water = 100/3/20, by weight, 24h) as compared with direct salting in the chopper, substantially reduced the cooking loss of pork batters, but only when the batters were relatively coarsely chopped. With more extensive chopping (exceeding 10–15 min at low chopper speed) no presalting effects were found, indicating that salt diffusion, protein dissolution and myofibril swelling were completed also in control batters salted in the chopper. Presalting of beef had a much weaker, although similar, effect on water retention properties.The practical implications are that presalting may help in reducing cooking loss of coarsely comminuted sausages, particularly pork products. Presalting, however, has no beneficial effect on finely comminuted, bowlchopper-produced sausages.     

Effects of PSE on the quality of cooked hams

Meat quality comparisons were carried out on hams produced from pork legs showing evidence of PSE and normal pork legs. Quality measurements included drip loss, sliceability, cooking loss, TBARS analysis and colour evaluation (Hunter L, a, b). A total of 40 pork legs were selected from a commercial slaughtering plant, 20 from carcasses showing PSE and 20 from normal carcasses based on L, a, b, and pH values. Carcass pH taken between the third/fourth rib was measured 45 min, 90 min, and 24 h after slaughter. Using a Minolta colorimeter (Hunter L, a, b,), colour of the Longissimus dorsi muscle was measured 24 h after slaughter. PSE had an adverse effect on cooked hams in comparison to normal cooked hams with respect to driploss (P<0.01), cooking loss (P<0.01), sliceability (P<0.01), colour (P<0.05) and lipid oxidation (P<0.05). Cooked hams manufactured from severe PSE pork in this study had an estimated financial loss of 50% (IRL￡4.90) in comparison to those manufactured from normal pork (IRL￡9.80).     

油脂预乳化液替代脂肪对乳化肠品质的影响

制备鱼油和玉米油预乳化液,研究油脂预乳化液替代猪背膘（质量替代比例分别为25%、50%、75%、100%）对乳化肠主要组分、蒸煮损失、色泽、质构特性、流变特性和感官特性的影响。结果表明：随着预乳化液替代比例的增加,脂肪含量显著降低（P＜0.05）;蒸煮损失也逐渐降低。油脂预乳化液处理组间硬度差异显著并明显高于对照组（P＜0.05）,随预乳化液替代比例增加,乳化肠硬度先增加后降低,当替代比例为50%时,硬度最大;弹性差异不显著（P＞0.05）,咀嚼性差异显著（P＜0.05）且变化趋势和硬度一致。温度扫描动态储能模量G’显示：与对照组相比,添加鱼油与玉米油预乳化液处理组的动态储能模量更高,且添加50%替代比例的预乳化液时,G’值最高。感官评价显示：预乳化液替代比例为50%时,乳化肠在外观、风味和总体接受度得分最高。因此,油脂预乳化液替代乳化肠质量50%的猪背膘可以有效降低乳化肠中脂肪含量,提高质构特性,改善产品的顾客接受程度。     

血浆蛋白粉与海藻酸钠对猪肉火腿肠品质的影响

考察血浆蛋白粉、海藻酸钠、蒸煮温度与蒸煮时间对猪肉火腿肠(PMS)品质特性(蒸煮损失率、色泽、硬度、弹性)的影响,以期获得低脂低盐高蛋白肉制品。结果表明:血浆蛋白粉显著降低PMS的蒸煮损失率和L*值,显著改善PMS的硬度(P<0.05);海藻酸钠能显著改善PMS的保水能力,但会导致PMS硬度和弹性的显著降低(P<0.05),而对PMS色泽无显著影响(P>0.05);优选的PMS加工条件为:血浆蛋白添加量2%,海藻酸钠添加量0.2%,85℃蒸煮20min。在此条件下,加工的猪肉火腿肠品质较佳。