食盐与超高压对低脂猪肉糜凝胶品质及热特性的影响

以含有0.2%海藻酸钠和1.8%大豆分离蛋白的低脂(≤2.0%)猪肉凝胶(LGPG)为对象,考察食盐添加量(0～2%)和超高压(300MPa)对LGPG品质及肉糜热特性的影响。结果表明:LGPG的蒸煮损失率和L*值随食盐质量分数升高而显著下降(P<0.05),保水率、a*值、b*值、硬度和咀嚼性则显著上升(P<0.05);300MPa处理可显著改善低盐(≤1.5%)LGPG的保水能力、硬度与咀嚼性;添加1.5%的食盐可显著降低肌球蛋白头部和肌动蛋白的变性温度,但会提高肌球蛋白尾部与肌浆蛋白的热稳定性;300MPa处理有降低肌球蛋白、肌浆蛋白和肌动蛋白热稳定性的倾向。     

脂肪含量对低盐猪肉凝胶品质的影响

以未添加磷酸盐的低盐猪肉凝胶作为研究对象,考察脂肪添加量(0～20%)对猪肉凝胶保水、质构和色泽的影响。结果显示,脂肪添加量在15%～20%范围内,凝胶保水性显著增加(P<0.05);添加5%以上的脂肪,可显著提高猪肉凝胶的L*值(P<0.05);在脂肪添加量不高于5%条件下,猪肉凝胶可形成良好的硬度、弹性、凝聚性和咀嚼性,并能保持较好的红度值(a*值),利于开发低脂猪肉制品。     

乳清多肽对猪肉糜氧化和凝胶特性的影响

目的：研究乳清多肽对猪肉糜氧化和凝胶特性的影响作用。方法：实验分为6 组,第1组为空白对照组,第2组加入20%（质量分数,下同）的乳清分离蛋白未水解物,第3～5组中分别加入10%、15%、20%的乳清分离蛋白水解物冻干粉,第6组中加入0.02%的丁基羟基茴香醚（butylated hydroxyanisole,BHA）。在肉糜冷藏7 d过程中测定过氧化值、羰基含量、巯基含量及凝胶的质构、白度、保水性、流变学特性的变化。结果：在贮藏初期,处理组和对照组之间无显著差异（P＞0.05）。贮藏7 d后,添加乳清分离蛋白水解物组在抑制氧化和保护凝胶品质方面都要比对照组和未水解组好（P＜0.05）。其中添加20%乳清分离蛋白水解物冻干粉的储能模量的极大值最高,而在抑制脂肪、蛋白氧化及保护凝胶质构、保水性方面,添加15%乳清分离蛋白水解物冻干粉效果更好（P＜0.05）,接近甚至达到了BHA组水平。结论：乳清多肽具有抑制猪肉糜氧化和保护肉糜凝胶品质的作用。     

淀粉种类对兔肉肉糜凝胶品质的影响

以兔肉为原料制备兔肉肉糜凝胶,测定兔肉肉糜凝胶的持水性、凝胶强度、冻融损失、乳化稳定性等,研究不同种类的淀粉对兔肉肉糜凝胶品质特性的影响。结果表明:添加的4种淀粉均可以显著改善产品的持水性、凝胶强度、冻融损失,使产品有良好的乳化稳定性,显微结构图显示添加淀粉后凝胶的结构得到明显改善,网状结构更加致密有序。同时,淀粉的添加还能改善产品的感官品质。变性淀粉对肉糜凝胶品质的影响要优于天然淀粉。4种淀粉中玉米变性淀粉的效果最好。     

不同种类脂肪替代物对牦牛肉糜凝胶品质特性影响的研究

该文研究了亚麻籽胶、魔芋胶、菊粉、大豆蛋白、胶原蛋白、乳清蛋白对牦牛肉糜的质构、乳化稳定性及感官评分等影响。结果表明,蛋白质类脂肪替代物中以添加量为14.5%的大豆蛋白最优,其可以提高牦牛肉糜的水分含量,显著提高流变性和硬度(P<0.01);碳水化合物类脂肪替代物中以添加量为3%的菊粉最优,其可以提高牦牛肉糜的流变性、保油性、硬度和咀嚼性。但是前者会显著降低牦牛肉肉糜的色泽、黏结性和感官品质,而后者不会对牦牛肉糜的品质造成不良影响。因此,添加量为3%的菊粉更适合作为牦牛肉糜的脂肪替代物。     

芦丁对冷藏猪肉糜脂肪和蛋白氧化及品质特性的影响

研究不同浓度(0、0.05、0.1和0.2 g/kg)的多酚物质芦丁对冷藏猪肉糜的抗氧化效果及其对肉糜品质特性的影响,并以0.2 g/kg叔丁基羟基茴香醚(butylhydroxyanisole,BHA)作为对照,测定了硫代巴比妥酸值(TBARS值)、总巯基含量、羰基含量、表面疏水性以及猪肉糜的色泽、蒸煮损失和质构特性。结果表明:芦丁对TBARS生成、总巯基损失、表面疏水性的增加具有一定的抑制作用,但对羰基含量不具有抑制作用,且高浓度芦丁反而促进了羰基氧化产物的生成;芦丁能提高肉糜红度值,减少蒸煮损失,并能提高熟肉糜的硬度和弹性等质构特性。因此,适量的芦丁对抑制猪肉脂肪和蛋白氧化以及改善其品质特性具有较好的作用。     

冷藏时间对冷却猪肉糜凝胶特性的影响

本文以托盘包装的冷却猪背最长肌为原料,在4 ℃条件下避光贮藏0、1、3、5和7 d后,分别加工成猪肉糜,分析猪肉糜pH、色差、蒸煮得率、质构和流变性的变化,研究不同冷藏时间对猪肉糜凝胶特性的影响。结果表明:随着冷藏时间的延长,猪肉糜的色差、蒸煮得率和质构呈下降趋势(p<0.05),说明猪肉糜凝胶性能变差。其中L^*值和蒸煮得率在冷藏0、1和3 d时,差异不显著(p>0.05)。流变结果表明,在72 ℃时,0、1 d和3 d的G'差异不显著,超过72 ℃后,G'在0和1 d时最大。综上,猪肉糜在冷藏3 d前进行加工,能够保持其良好的凝胶性能。     

马齿苋提取物抑制冷藏猪肉糜脂肪和蛋白氧化及对品质特性的影响

以新鲜猪肉为原料,制成肉糜后加入不同添加量(0.2、0.4、0.8 g/kg)的马齿苋提取物(Purslane extract, PE),并以0.8 g/kg丁基羟基茴香醚作为阳性对照,同时设置空白对照,研究猪肉糜冷藏期(1、3、5、7、9 d)硫代巴比妥酸(thiobarbituric acid, TBA)值、羰基含量、总巯基含量、表面疏水性、猪肉糜色泽及其质构特性的变化,评价马齿苋提取物对冷藏猪肉糜脂肪、蛋白质和品质等特性的影响。结果表明,0.8 g/kg马齿苋提取物能显著降低猪肉冷藏期间的TBA值、表面疏水性和羰基含量的增长幅度(P<0.05);0.4 g/kg马齿苋提取物在贮藏初期能有效降低总巯基含量下降的幅度(P<0.05);贮藏后期3个添加量之间的作用效果无显著性差异(P>0.05);0.2 g/kg马齿苋提取物能显著减缓a^*减小和硬度变大(P<0.05);马齿苋提取物还能降低肉糜黏聚性和L^*值(P<0.05);但对b^*值、咀嚼度和弹性影响不大。因此,3种浓度的马齿苋提取物均能在...     

甲基纤维素添加量对低盐肉糜凝胶特性的影响

将甲基纤维素(methyl cellulose,MC)作为替代物加入肉糜中等量替代食盐,采用5个不同MC添加量(0％、0.4％、0.8％、1.2％、1.6％)即肉糜中的食盐质量分数分别为2％、1.6％、1.2％、0.8％、0.4％.通过测定肉糜凝胶的蒸煮损失率、色泽、质构、低场核磁共振横向弛豫时间(T2)以及流变特性,...     

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...     

肉类的脂肪酸组成与膳食调节及其对肉类品质的影响

综述了肉类(猪、牛、羊)脂肪酸在脂肪组织和肌肉组织中的分布特点、脂肪酸组成的营养学缺陷、膳食强化多不饱和脂肪酸及其对肉类品质(风味、脂肪氧化和色泽等)影响的研究现状。当前的研究表明在适当强化多不饱和脂肪酸的同时补充较高浓度的维生素E可以在一定程度上抑制脂肪氧化和色泽的劣变及改善脂肪酸的组成。     

Comparison between rabbit lines for sensory meat quality

Rabbits from three synthetic lines were used in the experiment. Line R was selected for growth for 24 generations. Lines V and A were selected for litter size at weaning for 30 and 33 generations, respectively. Sensory analysis was carried out on the Longissimus muscle. The parameters evaluated were: juiciness (J), hardness (H), fibrousness (F), flouriness (Fl), intensity of rabbit flavour (IRF), aniseed odour (AO), aniseed flavour (AF), liver odour (LO) and liver flavour (LF). A Bayesian analysis was performed. Line V was only 82% as juicy as line R. Line V was 18% harder and 17% more fibrous than line R. Lines A and R had the same H and F. No differences in Fl were found. Small effects were found for flavour traits. We conclude that line origin has an influence on some sensory traits determining rabbit meat tenderness.     

Konjac gel fat analogue for use in meat products: Comparison with pork fats

The paper reports a study of the characteristics of konjac gel fat analogue as compared to types of pork fat for use in fat reduction strategies for meat products. Various characteristics—colour, mechanical/rheological behaviour and thermal properties—of pork fats (backfat-PBF and trimmed fat-PTF) and konjac gel (KFG) with different physical structures (intact or ground to 4 and 8 mm) were studied. Pork fat melting processes were evaluated by differential scanning calorimetry (DSC) at above- and below-zero temperature ranges with PBF and PTF always showing similar net results. KFG did not show any thermal event in the range from −40 to 100 °C except the freezing/melting of its constitutional water. While water and fat binding properties of pork fats were affected by fat type and structural disintegration (ranging between 0 and 77%), in all cases KFG presented excellent thermal water binding (<1%). As compared to KFG, PBF showed greater (P < 0.05) hardness, chewiness, penetration force, gel strength, extrusion force and work of extrusion. These differences were minimized after grinding. Kramer shear values in KFG were greater (P < 0.05) than in PBF when this was ground to 4 mm, but lower (P < 0.05) at 8 mm. The highest Kramer shear values (P < 0.05) were recorded in PTF irrespective of the degree of disintegration. Rheological analyses indicate that the behaviour of KFG, which is thermally stable, is predominantly elastic during heating and exhibits rheological thermal behaviour (at over 40 °C) similar to that of pork backfat.     

伊拉兔肉肌内脂肪酸组成及温度对其脂肪氧化的研究

研究了伊拉肉兔后腿肉的肌内脂肪含量,并分析测定了其脂肪酸组成,同时研究了兔腿肉在常温(15±0.5)℃和低温(4±0.5)℃贮藏条件下的脂肪氧化稳定性。结果表明,兔腿肉肌内脂肪主要含有19种脂肪酸,其中棕榈酸(16∶0)、硬脂酸(18∶0)、油酸(18∶1)、亚油酸(18∶2)的总含量占脂类总脂肪酸含量的71.06%左右。伊拉兔肉肌内脂肪中主要是不饱和脂肪酸,尤以多不饱和脂肪酸居多。在常温(15±0.5)℃和低温(4±0.5)℃贮藏条件下,兔腿肉POV、TBA值的差异极显著(p<0.01)。常温条件下,第5d兔肉出现异味并逐渐变成臭味,而低温条件下,第7d才开始出现轻微异味,低温冷藏对保证肉品质量有重要意义。      

薯类淀粉对兔肉肉糜流变性质和凝胶特性的影响

探讨木薯淀粉、甘薯淀粉和马铃薯淀粉对兔肉肉糜流变性质和凝胶特性的影响,研究了不同淀粉添加量时,兔肉肉糜弹性模量G'、质构特性、凝胶强度、保水性和色泽的变化规律。结果表明:升温过程中,兔肉肉糜的弹性模量G'经历了3个阶段的变化。首先在40~50℃,G'缓慢上升,接着在50~57℃,G'急剧下降,然后在57~80℃,G'快速上升,之后趋于稳定。降温过程中,G'逐渐升高。淀粉对兔肉肉糜在升温和降温过程中弹性模量的变化影响显著。添加淀粉能增加兔肉肉糜凝胶的硬度、胶着性和咀嚼性,降低其内聚性,而弹性则呈现先上升后下降的趋势。添加淀粉能增加兔肉肉糜的凝胶强度、持水性,同时降低压力失水率,同一添加量时,马铃薯淀粉对改善兔肉肉糜凝胶的品质、增加肉糜凝胶保水性的效果最好。添加淀粉能增加肉糜凝胶的亮度值和白度值,降低肉糜凝胶的黄度值,但淀粉的种类和添加量对兔肉肉糜凝胶的色泽影响不显著。3种薯类淀粉中,马铃薯淀粉的应用效果最好。     

纳米纤维素晶体的性能研究

竹子溶解浆经植物粉碎机预处理,再用硫酸水解制备纳米纤维素晶体(NCC)。利用马尔文激光粒度仪、扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、红外光谱(FTIR)、热重分析仪(TGA)对原料及纳米纤维素晶体的尺寸、形貌、晶体特性、结构和热性能进行表征。结果表明:NCC的Z均粒径为128.7nm;竹浆经机械粉碎部分纤维长链被切断;由TEM图观察可知NCC为棒状,直径5~10nm,长度100~200nm;竹浆及NCC属于纤维素Ⅰ型,结晶度由竹浆的64.27%提高到72.04%;FTIR图谱表明竹浆与NCC化学结构基本一致;TGA分析表明NCC的热稳定性低于竹浆,但NCC的降解速率较竹浆缓慢,并且NCC的热解残余率增大。     

Amorphous cellulose gel as a fat substitute in fermented sausages

Fermented sausages were produced with 25%, 50%, 75% or 100% of their pork back fat content replaced by amorphous cellulose gel. The sausage production was monitored with physical, chemical and microbiological analyses. The final products were submitted to a consumer study, and the volatile compounds of the final products were extracted by solid-phase microextraction and analyzed by GC/MS. The reformulated fermented sausages had significant reductions in fat and cholesterol, and the volatile compounds derived from lipid oxidation were also reduced in the final products. These results suggest that the substitution of up to 50% of the pork back fat content by amorphous cellulose gel can be accomplished without a loss of product quality, enabling the production of fermented sausages with the levels of fat and cholesterol decreased by approximately 45% and 15%, respectively.     

Seasonal effects on the patterns of deposition of water, fat and protein in rabbit meat

The effect of season on the patterns of deposition of water, fat and protein and on the changes in the chemical composition of total meat, meat from hind leg and M. longissimus lumboris, was studied in rabbits from 1 to 20 weeks of age. Allometric coefficents changed in a continuous way although changes were more marked in the first weeks of postnatal life. Relative rates of deposition increased for fat and decreased for water and protein throughout the experimental period, irrespective of the season or part considered. There were significant seasonal effects on most of the chemical components that affected the initial values of allometric coefficients, and thier later rates of change, but not the pattern of variation. As a consequence, modification of the chemical composition of meat was also significantly influenced by season, but differences were numerically very small. At birth, meat from rabbits born in summer had a lower content of fat and higher of water and protein than that from rabbits born in other seasons. Rates of deposition in postnatal life determined that the chemical composition tended to be similar to that of rabbits grown in other seasons. A tendency towards a higher degree of fatness in older animals was also observed in this season.     

肉丸的食用品质特性研究

用猪、牛肉（各５０％）为原料,通过添加不同的配料生产肉丸子,并用仪器对各组肉丸的品质特性进行客观评价。结果表明：１滋嫩度：Ｂ组、Ｃ组优于对照组和Ａ组（Ｐ＜０．０１）,Ａ组优于对照组（Ｐ＜０．０５）;２色泽：对照组、Ａ组的色泽略深于Ｂ组、Ｃ组（Ｐ＞０．０５）;３感官评定：各组综合评分结果为良好,其中Ｂ组的香味、口感等食用性能最佳。说明适量添加淀粉、肥膘等于肉丸中,能改善其食用性能;猪、牛肉混合生产的肉丸子,其食用特性优于牛肉丸子。     

獭兔与肉兔肉中羟脯氨酸含量的比较研究

取獭兔和肉兔的腰部肌肉为样品,按照GB/T9695.23-2008测定羟脯氨酸含量,并进行方差分析。分析检测结果表明,羟脯氨酸含量分别为:公獭兔0.150±0.014%,母獭兔0.165±0.047%、公肉兔0.115±0.027%、母肉兔0.110±0.007%;方差分析表明,獭兔和肉兔在不同品种和不同性别间,腰部肌肉中羟脯氨酸含量差异均不显著。