去骨方法对牛肉和火鸡肉化学成分及一些特性的影响

本文针对机械去骨和人工去骨的牛肉以及火鸡肉的一些化学、物理特性进行了对比研究。相近成分胆固醇、硫代巴比土酸(TBA)、钙铁含量、颜色参数、脂肪酸成分等指标在样本中得以分析。去骨方法对牛肉和火鸡肉的化学成分有所影响。机械去骨导致较高的胆固醇以及钙铁含量。在手工去骨火鸡肉中,含量最多的脂肪酸是C16:0、C18:1以及C18:2。机械去骨加工使火鸡肉中C18:1、C18:2、C18:3的含量增加。而C16:0、C18:0、C18:1则是机械去骨和手工去骨牛肉中主要的脂肪酸。     

磷酸盐和氯化钙对牛肉凝胶特性的影响

本文主要研究磷酸盐和氯化钙对牛肉凝胶特性及颜色的影响.结果表明磷酸盐的使用量对凝胶硬度影响差异不显著,会显著提高凝胶弹性和粘聚性,但会使L值和a值逐渐降低,说明磷酸盐对牛肉颜色有不良影响.不同部位的牛肉之间的凝胶硬度、弹性和粘聚性差异显著,注射CaCl2对凝胶特性有一定影响,且能显著提高各部位的亮度L值,但对红色度a值影响差异不显著.     

大豆分离蛋白对调理重组牛肉品质特性的影响

为探讨大豆分离蛋白添加量对调理重组牛肉制品品质特性的影响,以碎牛肉为实验原料,经过调理和重组工艺,研究不同大豆分离蛋白添加量对产品的各项品质特性的影响。结果表明:随着大豆分离蛋白添加量的增加,调理重组牛肉制品的解冻损失显著降低(P0.05),出品率显著提高(P0.05),产品的质构特性得到显著改善(P0.05),黏结强度显著增强(P0.05),但是产品的色泽变暗(P0.05)。另外,低场核磁检测发现,增加大豆分离蛋白的添加量,T_(2b)和T_(21)的弛豫时间均逐渐变短,而T_(22)的弛豫时间逐渐延长,说明产品的保水性逐渐增强。对产品进行感官评价表明,大豆分离蛋白添加量为2.0%时,产品品质最好。综合考虑产品品质和感官质量,确定在调理重组牛肉制品中大豆分离蛋白的最佳添加量为2.0%。     

去骨凤爪凝胶特性影响因素的研究

以市售凤爪为原料,建立凤爪凝胶特性的综合评价指标,研究压力、pH、氯化钠添加量和柠檬酸钙添加量对去骨凤爪凝胶强度、弹性、脆度和持水率的影响。试验结果表明：四个单因素均能显著提高凤爪的凝胶性能。各因素对去骨凤爪凝胶特性综合指标影响的主次顺序为：氯化钠添加量〉柠檬酸钙添加量〉压力〉pH。由正交试验结果表明去骨凤爪凝胶特性最佳的组合为：500MPa压力下保压25min、pH4.0、氯化钠添加量为1.0%,柠檬酸钙添加量为0.04%。在此组合下,去骨凤爪凝胶特性最好,综合指标为94.765。     

食盐和大豆蛋白对牛肉凝胶特性的影响

主要研究了食盐和大豆蛋白对牛肉凝胶特性及颜色的影响,结果表明:随食盐添加量的增加,牛肉糜的凝胶硬度、弹性和粘聚性均增加,亮度L值显著降低,对红色度a值影响不显著;随大豆分离蛋白添加量的增加,凝胶硬度逐渐增加,弹性逐渐降低,对粘聚性的影响不显著,并使牛肉糜的亮度L值显著降低,但对红色度a值影响不显著。     

辐照剂量率对牛肉脂肪和蛋白氧化及蛋白特性的影响

为研究电子束辐照剂量率对冷却牛肉脂肪和蛋白氧化及蛋白理化特性的影响,试验分析了电子束辐照处理不同剂量率对脂肪和蛋白氧化程度及其蛋白溶解性、疏水性与持水力等特征指标的影响。结果表明:2 k Gy电子束辐照后牛肉脂肪及蛋白氧化程度显著加剧,蛋白溶解性及持水力显著降低,疏水性显著增加(p0.05);在0~2500 Gy/s剂量率范围内,随着剂量率的增大,牛肉的TBARS、酸价、过氧化值、羰基和二硫键含量降低,巯基含量上升,脂肪及蛋白氧化程度减弱;剂量率与蛋白溶解性和持水性呈显著正相关,而与疏水性呈显著负相关(p0.05)。试验结果进一步证明了电子束辐照剂量率会显著影响牛肉脂肪及蛋白氧化。辐照氧化导致蛋白结构的破坏,引起蛋白理化特性的显著变化(p0.05),这为电子束辐照过程中冷却牛肉的氧化控制提供理论参考。     

肌浆蛋白对牛肉匀浆物凝胶特性的影响

本文采用单因素三水平完全随机试验设计,研究了3种不同肌浆蛋白含量的牛肉匀浆物的凝胶特性。试验结果表明,肌浆蛋白含量对牛肉匀浆物凝胶的保水性有极显著的影响(p<0.01),未分离肌浆蛋白的牛肉匀浆物凝胶保水性为92.28%,而完全分离肌浆蛋白的牛肉匀浆物凝胶保水性为98.88%;肌浆蛋白含量对凝胶破断应力有显著影响(p<0.05),未分离肌浆蛋白的牛肉匀浆物凝胶破断应力为7.32×10-6kPa,部分分离和完全分离肌浆蛋白的牛肉匀浆物凝胶破断应力分别为14.91×10-6kPa和12.92×10-6kPa;肌浆蛋白含量对凝胶应变影响不显著。     

食用胶对重组牛肉加工特性的影响

将转谷氨酰胺酶和酪蛋白酸钠作为重组牛肉使用的黏合剂,添加量为原料牛肉质量的1.2%。在此基础上,分别添加0.3%(m/m)的卡拉胶、亚麻胶等多种食用胶,通过测定黏结性、色差、解冻损失、蒸煮损失、尺寸变化、剪切力、质构来说明食用胶对重组牛肉加工特性的影响。研究结果表明,亚麻胶和黄原胶都显著降低了重组牛肉的黏结性(P ＜ 0.05),且成片性不好。卡拉胶能增加a* 值,δ- 葡萄糖酸内酯(GDL)和卡拉胶的复合胶却降低了a* 值。添加结冷胶、亚麻胶和黄原胶均降低重组肉的解冻损失和蒸煮损失,而且添加亚麻胶和黄原胶的重组牛肉嫩度最大。     

斩拌时间和pH值对牛肉凝胶特性的影响

主要研究pH值和斩拌时间对牛肉糜凝胶特性及颜色的影响 ,确定最佳的斩拌条件。结果表明 ,当肉糜的酸碱度由酸性向中性靠拢时 ,牛肉糜制品的凝胶硬度、弹性、粘聚性均逐渐增大 ,牛肉糜制品的硬度、弹性、粘聚性随着斩拌时间的增加先增大后减小。在斩拌2 0min时达到最高值     

机械去骨禽肉糜的应用及研究进展

介绍国内外机械去骨禽肉糜(MDPM)在食品中的应用及其在应用中出现的问题,如乳化、脂肪氧化、血红素氧化等,并探讨其开发利用前景.     

Effects of different cooking methods on some chemical and sensory properties of Galega kale

Kale (Brassica oleracea L. var. acephala) is rich in bioactive phytochemicals such as phenolic compounds and vitamins. However, cooking the plants can cause important changes in composition. The objective of this study was to investigate the effect of some domestic cooking processes (boiling, steaming, microwaving and pressure cooking) on several quality parameters of Galega kale. Boiling had the strongest effect on the antioxidant capacity (the IC₅₀ was four times higher than in the fresh sample), total phenolics (losses of 76.4–77.9%) and colour (ΔE = 17.79–19.12). Microwaving caused the greatest loss of soluble solids (80.8–82.2%). Steaming seems to be the best method for retaining the nutrient and antioxidant capacity of kale (100% ash, 71–77.5% soluble solids, 100% antioxidant capacity, 67–71% total phenolics, 62–71% chlorophyll). However, steamed kale was awarded the lowest sensory scores, indicating the difficulty in reconciling nutritional value and sensorial quality. Use of discriminant statistical techniques enabled the classification of 100% of samples.     

The effects of different plant oils on some emulsion properties of beef, chicken and turkey meats

The effects of different plant oils (soybean, hazelnut, canola, sunflower, corn, cotton and olive) on emulsion capacity (EC), emulsion stability (ES), emulsion density (ED) and apparent yield stress values of emulsion (raw emulsion; AYSe) and emulsion gel (cooked emulsion; AYSg) of beef, chicken and turkey meats were studied by using a model system. Olive oil increased EC, AYSe and AYSg values and corn oil increased ES values significantly (P < 0.01). Moreover, olive oil decreased ED values significantly (P < 0.01). The effects of chicken meat on EC, turkey meat on ES and beef on AYSe were found to be significant (P < 0.01). The plant oils increased EC values of chicken meat significantly (P < 0.01). Olive oil had higher effect on EC values of chicken, beef and turkey meat. It was found to be 140.7, 132.5 and 128.9 mL (450 mg)⁻¹ protein, respectively. However, olive oil had higher effect on AYSg values of turkey, chicken and beef. It was found to be 492.9, 492.3 and 487.7 Nm⁻², respectively. In addition, olive oil decreased ED values of beef significantly (P < 0.01). The effect of corn oil on ES values of beef was found to be higher (P < 0.05) as 75.77%.     

Hot deboning beef with and without electrical stimulation

Two hot deboning procedures for producing vacuum packed primal beef joints were compared with conventional side chilling followed by cold deboning. Cold shortening toughness was avoided in the hot procedures either by a delay before chilling or by electrical stimulation of the carcass. Overall evaporative losses were 0·6% with hot deboning and 1·9% with cold deboning. Hot deboning reduced drip loss but the effect was smaller after electrical stimulation. The colour of large muscles which cool unevenly on the side was more uniform after hot deboning, but again the improvement was smaller after electrical stimulation. There was no difference in bacterial contamination or growth on hot and cold deboned meat, and instrumental and sensory assessments confirmed that eating quality was similar for all three treatments.     

Influence of cooking methods on the nutritive value of turkey meat

Selected culinary parts of turkey meat were subjected to a differentiated cooking method. The chemical composition and -SH group levels were studied in both raw and cooked turkey meat and indices of nutritive value were determined. The turkey meat was shown to be characterized by a high nutritive value, irrespective of any cooking method. A slightly unfavourable effect was found to be exerted on the nutritive value of meat by microwaves. Fried and roasted meat was characterized by high values of PER (3.1) and BV (83.8). Lower index values were found for microwaved meat [PER (2.8); BV (82.2)].     

Observations on some chemical and physical characteristics of buffalo meat

Proximate composition, sarcoplasmic and myofibrillar protein fractions of buffalo meat were similar to those of beef. Buffalo meat was also rich in lysine. Meat from young animals had a lower collagen content than that from old ones. As the temperature of holding the carcasses was increased, the rate of pH fall was faster. Meat from stressed animals showed a higher ultimate pH. Percentage of cooking loss and thermal shrinkage was higher in muscles of old animals than in young ones, which probably reflected the poor condition of the older animals. Meat cooked by pressure cooking showed lower Warner-Bratzler shear values as compared with meat cooked in boiling water.