Factors affecting the eating quality of pork

In the last decade studies with the specific objective of improving the sensory quality of pork have come to the forefront of meat research, likely a result of consumer complaints of blandness levelled against modern lean meat and the frequent reference to the more strongly flavored meat that was available years ago. Regardless of the lack of scientific evidence to substantiate or refute these claims, the consumer perception of deteriorated quality is real and presents a challenge for the pork industry. Hence, this review has been undertaken with the aim of providing insight into potential sources of amelioration of the eating quality of fresh pork. Existing works are collated, encompassing animal effects, such as, species, breed, muscle type, fat, and ultimate pH, as well as environmental influences, including pre-slaughter conditions of and housing and exercise, and post-slaughter parameters, such as, electrical stimulation, chilling, and cooking.     

蛋白质与大米食味品质的相关性分析

利用国标方法对大米的食味品质进行了评价,并开展了蛋白质含量及组成与大米食味品质的相关性研究。结果表明,大米蛋白质的含量与其食味品质之间存在着显著的负相关关系(p<0.05),说明与相似品种的大米相比,蛋白质含量较低的大米具有较好的食味品质。大米中蛋白质含量的变化,首先对米饭的食用滋味产生影响,其次是米饭的适口性、光泽、气味与外观。大米蛋白质组分中,清蛋白是影响大米食味品质最显著的组分,碱溶谷蛋白和醇溶蛋白的含量与大米的食味品质及某些食味特性之间存在一定的负相关关系,球蛋白与大米食味品质不存在负相关关系。     

Influence of dietary fat on pork eating quality

This study compared the influence of dietary fat sources on meat quality, fatty acid composition and sensory attributes in pork. The experiment was conducted with 43 entire male pigs (Pietrain×(Landrace×Large White)) which were fed a basal diet without added fat (control diet) or supplemented with different sources of fat: animal fat (1%, AF1; 3%, AF3), soyabean oil (1%, SBO1) and calcium soaps of palm oil (1%, CaSPO1). Dietary fat supplementation did not significantly affect ultimate pH, colour, Warner-Bratzler shear force values, sensory attributes or SFA. Pigs fed SBO1 had the lowest proportion of MUFA and the highest of PUFA. In conclusion, these dietary fat sources could be recommended for inclusion in diets, at these levels, with no detrimental effect on eating quality. Despite finding no significant differences, the PCA afforded a comprehensive view of the predominating attributes of pork from animals fed the different fats.     

煎、炸、烤对横山羊肉食用品质的影响

以横山羊肉为研究对象,通过调控处理时间和温度,进行煎、炸、烤三种工艺处理,采用质构仪测定肉样的全质构和剪切力,用测色仪测定肉色,进而对肉样的食用品质进行综合评价。结果表明:对于煎制处理,2min和3min处理的肉样硬度、咀嚼性及回复性显著小于4min(P0.05);2min和3min处理的肉样剪切力显著小于4min(P0.05);肉样L*值随处理时间的延长逐渐减小(P0.05),2 min和3 min处理的肉样a*值小于4min(P0.05),而b*、c*及h°值大于4min(P0.05)。对于炸制处理,3 min处理的肉样硬度和内聚性显著小于4 min和5 min(P0.05),咀嚼性、弹性及回复性显著小于5min(P0.05);3 min处理的肉样剪切力显著小于4min和5min(P0.05);3min处理的肉样a*值小于5min(P0.05),其他肉色指标对不同的处理时间差异不显著(P0.05)。对于烤制处理,160℃处理的肉样硬度、内聚性和回复性小于180℃(P0.05),弹性小于200℃(P0.05);160℃处理的肉样剪切力显著小于200℃(P0.05);160℃处理的肉样L*值小于180℃和200℃(P0.05),a*和c*值小于200℃(P0.05),h°值大于200℃(P0.05),b*值对不同的烤制温度无显著差异(P0.05)。综合分析表明:煎、炸、烤三种高温处理对横山羊肉食用品质有较大影响,肉样在226~228℃的温度下煎制处理3 min和炸制处理3min、在160℃的温度下烤制处理40min,均具有较高的食用品质。该研究结果对于人们选择合理的羊肉高温处理方式及工艺条件具有一定的指导意义。     

猪肉盐溶蛋白质热诱导凝胶功能特性的研究

以猪背最长肌为材料,采用L9(34)正交设计及混料回归分析研究了猪背最长肌盐溶蛋白质热诱导凝胶保水性和凝胶超微结构。结果表明,猪背最长肌最佳提取条件为MgCl2浓度0.01mol/L、NaCl浓度0.6mol/L、提取液pH7.0,其凝胶的保水性为69.26%。扫描电镜研究结果显示,保水性不同的凝胶,其超微结构表现出很大的差异, 保水性为69.26%,其凝胶的网络比较均匀、细致,蛋白束平滑;保水性为37.81%,其凝胶的网状结构粗糙、疏松、不均匀。     

两段式冷却急冷温度对冷却猪肉品质的影响研究

研究了不同急冷温度(-14、-18、-22、-26、-30℃)对冷却猪肉品质的影响。结果表明,急冷温度的变化对冷却肉食用品质有显著影响(p<0.05),急冷温度为-22℃能显著提高冷却肉的保水性,改善色泽和质构,降低胶着性、咀嚼性和硬度,但对黏着性和弹性无显著影响;宰后45min胴体温度和pH对冷却肉保水性有预测作用,pH45min与冷却猪肉失水率呈负相关,宰后45min的胴体温度与失水率呈正相关。     

Influence of dietary oils and protein level on pork quality. 1. Effects on muscle fatty acid composition, carcass, meat and eating quality

This study evaluated the effects of three dietary oils - palm kernel (PKO), palm (PO) and soyabean (SBO) - and two protein levels - high (HP) and low (LP) in a 3×2 factorial design involving 60 pigs on growth performance, muscle fatty acid composition and content, carcass, meat and eating qualities. Oil type did not have a significant effect on growth and carcass quality. PKO significantly reduced the polyunsaturated (PUFA) to saturated (SFA) fatty acid (P:S) ratio in longissimus muscle (P<0.001). PKO increased the concentrations of lauric (12:0), myristic (14:0), palmitic (16:0) and stearic (18:0) fatty acids and decreased linoleic acid (18:2). The LP diet increased intramuscular fat (IMF) from 1.7g/100g muscle in HP to 2.9g/100g (P<0.001), increased tenderness by 0.6 units (P<0.01) and juiciness by 0.5 units (P<0.01) on the 1-8 scale, but at the expense of lower daily weight gain (P<0.01), lower feed conversion efficiency (P<0.01), reduced P:S ratio (P<0.001) and increased lipid oxidation (P<0.01). The results suggest that PKO and PO could be used in tropical developing countries as cheaper alternatives to SBO for the production of good quality and healthy pork, but their limits of inclusion need to be determined.     

几种保湿剂对宁乡花猪肉干食用品质的影响

主要采用感官检验及测定水分含量的方法,分别研究了山梨醇、甘油、甘露醇、多聚磷酸钠等4种保湿剂对宁乡花猪肉干食用品质的影响。结果表明,这4种保湿剂对猪肉干食用品质具有明显改善作用。最合适的添加量分别为:山梨醇4g/100g、甘油3m L/100g、甘露醇4g/100g、多聚磷酸钠0.2g/100g。其中甘油的效果最好,在其最适添加量为3m L/100g时,肉干感官评分为92,水分含量为45.1%,空白对照肉干样品感官检验评分为65,水分含量为31.5%。     

红烧肉加工过程中主要营养品质和食用品质的变化规律研究

研究红烧肉加工过程中原料肉、料酒浸泡、油炸、炖煮、红烧等加工关键节点处其主要营养品质和食用品质的变化,为较全面的了解其品质形成规律提供理论依据。对红烧肉加工过程中主要营养品质指标及颜色、质构、风味进行测定。结果表明,红烧肉加工过程中水分含量呈下降趋势;蛋白质变化规律不明显;脂肪含量先下降后上升,炖煮之后又有所下降;总糖含量在最终产品阶段显著提高。加工过程中红烧肉的瘦肉、肥肉和皮三部分颜色均发生变化,L*值显著降低(p<0.05);a*值先下降后显著上升(p<0.05);瘦肉和肥肉b*值显著增加(p<0.05),皮部分b*值在前六个加工点处变化不显著(p>0.05)成品时显著上升(p<0.05)。剪切力和质构分析表明,加工中红烧肉的弹性显著增加(p<0.05),剪切力、硬度显著降低(p<0.05);瘦肉部分的粘聚性显著上升,肥肉部分显著下降(p<0.05),皮整体变化不显著(p>0.05);瘦肉和肥肉部分的咀嚼性显著下降(p<0.05),而皮部分的咀嚼性显著上升(p<0.05)。对电子鼻传感器信号数据进行主成分分析发现,前三个加工节点除了第二和三、三和四存在差异但不显著外(p>0.05),与其他加工节点的差异性都显著(p<0.05)。第四个加工节点与第三、五、六个加工节点的差异不显著(p>0.05),而与其他三个加工节点差异显著(p<0.05),后3个加工节点处香气特征相似。      

猪肉肉质和风味的提高与改善

介绍了影响猪肉肉质的因素和改善肉质的方法,主要有营养调控和管理方式的改善。     

烤制羊肉食用品质评价指标筛选研究

以市售羊的通肌、后腿和脖子肉为原料,对其进行烤制之后,参照国家标准GB/T16861—1997的方法进行感官评价,结合M值、主成分分析和相关性分析方法对烤制羊肉的食用品质评价指标进行筛选。结果表明,烤制羊肉食用品质评价指标主要是质地和风味,其中,韧性、硬度、结缔组织含量可以评价机械质地,多汁性和润滑性可以评价表面质地,风味主要由肉香味评价;相关性分析表明,质地指标中韧性与硬度、结缔组织含量有较强的相关性(R2分别为0.79,0.76),多汁性和润滑性有较强的相关性(R2为0.71),即硬度和结缔组织可以用韧性表示,润滑性可以用多汁性表示。研究结果显示韧性、多汁性和肉香味可以作为评价烤制羊肉食用品质的评价指标。     

Effect of the combination of various NaCl levels and soy protein isolate on the quality characteristics of smoked pork loins

The objectives of this study were to evaluate the physicochemical, textural and sensory properties of smoked pork loins (PL) containing various levels of NaCl (0.0–2.0%) alone or in combination with soy protein isolates (SPI; 1.0%). The pH values, moisture, fat, and protein contents (%) of smoked PL were 5.97–6.17, 63.3–69.1%, 2.64–4.26%, and 20.2–26.6%, respectively. Increased NaCl levels increased moisture contents (%) and sensory scores, as well as reduced Hunter redness and yellowness and cooking loss (CL, %) (P < 0.05). A NaCl level of 1.0% had resulted in a CL (%) level similar to those at regular‐salt levels (1.5% and 2.0% NaCl). When 1.0% SPI was incorporated with smoked PL, the NaCl level of 0.5% was also similar to the CL (%) at higher NaCl levels and improved sensory scores. Thus, a NaCl level of at least 1.0% was required for the manufacture of smoked PL; however, smoked PL could be manufactured with 0.5% salt when 1.0% SPI was included as part of the manufacture of smoked PL to effect quality characteristics similar to those achieved with regular‐salt (1.5% and 2.0% NaCl) smoked PL.     

鹰嘴豆分离蛋白对减盐猪肉糜凝胶品质的影响

为探究鹰嘴豆分离蛋白(chickpea protein isolate, CPI)不同添加量对2种盐含量(质量分数1.4%和2%)猪肉糜凝胶品质的影响,将猪瘦肉与猪背膘斩拌成肉糜,分别设置不同盐含量和鹰嘴豆分离蛋白的处理组并加热制成凝胶。测定猪肉糜凝胶的色泽、乳化稳定性、质构、水分分布和流变特性。结果表明,在不添加鹰嘴豆分离蛋白的条件下,1.4%食盐质量分数的猪肉糜凝胶的汁液流失和硬度值显著高于2%食盐浓度的猪肉糜凝胶;相同食盐浓度条件下,随着CPI添加量的增加,猪肉糜凝胶的a^*值、b^*值、硬度、弹性、咀嚼性以及不易流动水比例均显著增加(P<0.05),动态流变储能模量G′值升高,汁液流失率显著降低(P<0.05),并在CPI添加量为1.2%时达到最大值或最小值;在相同CPI添加量条件下,1.4%食盐1.2%CPI的猪肉糜凝胶的储能模量G′值高于2%食盐1.2%CPI的猪肉糜凝胶,且2组凝胶的不易流动水比例、乳化稳定性、质构特性无显著差异(P>0.05)。综上,鹰嘴豆分离蛋白的添加能够在降低食盐用量的同时提升猪肉糜的凝胶品质...     

壳聚糖对冷却猪肉品质特性的影响研究

对壳聚糖在贮藏期间对冷却猪肉的感官性状(色泽、持水力)、理化品质(pH值、TBA、TVB-N)和微生物品质(菌落总数)的影响进行研究。添加壳聚糖能够明显的抑制微生物的生长(p<0.05),随着壳聚糖添加浓度的增大,脂质氧化率、挥发性盐基氮增加率及pH值上升率均下降,而持水力则呈现上升趋势。经过1.5%壳聚糖处理的样品在各方面的综合品质最好。     

不同淀粉对猪肉丸品质的影响

实验主要研究马铃薯淀粉、小麦淀粉、绿豆淀粉和木薯变性淀粉在加工温度为70、80、90℃和100℃对猪肉丸品质的影响。通过感官评定、测定色差、蒸煮损失、质构来比较猪肉丸品质的差异。实验结果得出:木薯变性淀粉做出来的猪肉丸在感官评价、蒸煮损失率、硬度、弹性和咀嚼性比其它三组淀粉表现出的效果好,加工温度为90℃时猪肉丸的感官评价、硬度、弹性和咀嚼性最大。     

维生素E对猪肉品质的影响

主要介绍维生素E独特的抗氧化作用,以及维生素E是如何支持肉类的稳定性。此外,还介绍了维生素E的作用方式,添加要求和功效。     

激光散射技术在PSE猪肉鉴定中的应用研究

目的基于新兴的激光光散射技术,用已知品质的肉样为研究对象,通过测定其蛋白溶液的颗粒光散射特性,寻求一个特征指标来判别正常猪肉与PSE肉,进而判断该技术在PSE肉鉴定方面是否可行。方法利用激光散射技术(动态光散射和静态光散射)比较正常猪肉和PSE肉总蛋白这两种溶液的颗粒光散射特性。结果不同p H对正常猪肉总蛋白溶液的颗粒特性有较大影响:低盐度时,其分维系数df随p H的增加而减小;盐浓度对正常猪肉总蛋白的df则影响较小。同时,相同溶液环境下,PSE猪肉蛋白和正常猪肉蛋白的分维系数(df)具有差异性,即两者蛋白颗粒特性具有明显差异。结论针对食品蛋白体系,在一定蛋白浓度范围内,光散射技术是一种较为有效的方法。该技术具有用量少、用时短、精度高、无损伤接触等优点,在食品品质快速分析检测方面具有潜在的应用价值。     

不同浓度卡拉胶对猪肉品质影响的研究

试验研究了不同浓度卡拉胶对猪肉的感官品质、色泽、保水性、蒸煮损失率及嫩度等品质指标的影响。结果表明,添加不同浓度的卡拉胶后,对猪肉的感官品质有一定的影响,对猪肉的色泽有负面的影响,不同浓度影响效果不同,一般高浓度的对猪肉感官品质的负面影响较大。卡拉胶浓度与猪肉的感官评分、剪切力之间的回归方程均具有统计学上的显著意义,与猪肉的色差、保水性及蒸煮损失率之间的回归方程不具有统计学上的显著意义。     

Production systems and influence on eating quality of pork

The present paper reviews the available information on the eating quality of pork from the perspective of production systems considered at farm level. Among the specifications differentiating systems having a claim on eating quality, breed, feeding strategy, rearing conditions and slaughter age/weight of the pigs may influence pork eating quality. Specific genetic X environment interactions such as the use of slow growing-fat local breeds reared in extensive conditions, as encountered in local Mediterranean systems, lead to high eating quality of pork and pork products Organic production per se has little influence on the eating quality of pork. Welfare-oriented specifications such as enriched living environment, outdoor access or free-range rearing have limited consequences on pork quality. Because boar taint negatively impacts the consumer acceptability of pork, a total ban on castration to improve animal welfare would be a real challenge for the management of pork quality in those countries where entire male pig production is not currently common.     

蒸汽—微波同步加热对排骨品质的影响

目的:探明排骨在蒸汽—微波同步加热过程中的变化规律。方法:采用蒸汽和微波组合同步加热,对处理后排骨的理化、质构、脂肪酸、氨基酸、蛋白总巯基和羰基含量进行研究。结果:与单独蒸制相比,蒸汽—微波同步加热可明显缩短烹饪时间,微波中低火(500 W)结合蒸汽(1300 W)加热(MS-13)缩短了48%的烹饪时间;与其他蒸汽—微波同步加热处理组相比,MS-13组排骨肉具有最高的水分含量、蛋白质含量和巯基含量,分别比单独蒸制组高5.91%,5.85%,101.60%,比微波组高14.55%,4.90%,19.78%;MS-13组排骨肉具有最低的脂肪含量和羰基含量,分别为单独蒸制组的91.87%和45.02%以及单独微波组的95.48%和67.18%;相对于新鲜样品,MS-13组样品不饱和脂肪酸相对含量明显增加。结论:微波中低火结合蒸汽加热13 min后的排骨肉具有较好的感官和营养品质。