Depression of aw by Soluble and Insoluble Solids in Alginate Restructured Beef Heart Meat

Water activity (a_w), pH, bind and moisture of alginate restructured beef heart meat (BHM) were evaluated using a 2⁵ factorial design based on combinations of beef heart meal and glycerol (10%, 20%), and dextrose, bone meal and glycine (0%, 5%). Effects of these components were significant (p<0.05) for reducing a_w and moisture, and, excluding glycine, for altering pH. The a_w of the BHM control was 0.94, while a_w for 32 treatments ranged from 0.66 to 0.90. Glycine lessened product bind. An intermediate moisture BHM product could be formulated using the hurdle concept and the alginate system for restructuring meat with incorporation of selected soluble (glycerol, dextrose) and insoluble (beef heart meal, bone meal) components.     

添加不同用量花生的重组牦牛肉饼的理化和感官特性研究

探讨在重组牦牛肉饼中添加不同量花生仁粉后的物理化学和感官特性变化,并确定花生仁粉的用量。牦牛肉经绞细后分别添加0、5%、10%、15%、20% 花生仁粉,经过24h 低温腌制,并在－ 20℃冻藏后,对肉饼的解冻损失、保水和保油性、烤制得率、烤制前后pH 值、色差和质构以及烤制后感官特性进行测定。结果表明：生牦牛肉饼中添加花生仁粉有增加黏附性的趋势(P ＜ 0.01),但不影响硬度、弹性、黏聚性、咀嚼性和韧性(P ＞ 0.05);添加花生仁粉显著降低了烤制后牦牛肉饼的硬度、黏聚性、咀嚼性和韧性(P ＜ 0.01)、提高了肉饼的黏附性(P ＜ 0.01),而不影响肉饼的弹性(P ＞ 0.05)。烤制得率和保水率随着花生仁粉添加量的增加而显著增加(P ＜ 0.01),而保油性则不受影响。添加花生仁粉不影响色差L* 和a* 值(P ＞ 0.05),但是,当花生仁粉添加量为15% 或20% 时,b* 值明显升高。此外,随着花生仁粉用量的增加,质构得分显著减低,总体接受程度以添加5%～15% 为佳。花生仁粉添加量高于15% 时,肉饼产生较强的豆腥味。     

Microbial Characteristics of Flaked and Color-Modified Turkey Thigh Meat

Effects of flaking and color modifying (treatment with pH 5.8, 7.4 and 8.0 phosphate buffers) boneless, skinless turkey thighs on microbial numbers were determined. Aerobic, psychotrophic, and coliform analyses were conducted on intact thigh (IT) before processing and on flaked turkey (FT) and color-modified turkey (CMT) held up to 5 days at 3°C and for 30 days at -20°C. Aerobic and psychrotrophic counts were not different (p > 0.05) between IT and 1-day FT or between FT and CMT at any sampling interval. Mean coliform levels in FT did not differ (p < 0.05) from those in CMT after 1 day at 3°C. Properly performed flaking and color modification do not compromise the microbial quality of turkey.     

Quality Characteristics of Restructured Beef Steaks Manufactured by Various Techniques

Beef (9–11% fat) was restructured with each of six mechanical treatments including chunking, fiberizing, slicing, chunking + slicing, slicing + water, and tenderizing each in combination with addition of 0.5% sodium chloride (salt)/0.5% phosphate, 0.5% Na-alginate/0.5% Ca-lactate, 0.5% Na-pectate/0.5% Ca-lactate, or no additives (control). Beef steaks restructured with salt/phosphate had lower (P<0.05) purge losses: higher binding force and bind scores than control products. Steaks restructured with Na-alginate/Ca-lactate had lower cooking losses and higher bind scores than controls. Use of Na-pectate/Ca-lactate did not improve (P>0.05) purge loss, cooking loss, binding force or sensory properties. Chunked meat or mixtures of chunked and sliced meats in combination with salt/phosphate or Na-alginateica-lactate resulted in steaks with acceptable bind and textural properties.     

肌肉组织学特性与肉品质的关系

畜禽的肉品质受多种因素的影响,其中与肌肉组织学特性关系最为密切。骨骼肌是主要的可食性肉,它由肌纤维、结缔组织和肌内脂肪组成。本文综述了肌纤维类型、肌纤维直径、肌纤维密度、肌纤维面积比例、肌节长度、结缔组织特性、肌内脂肪含量与分布等肌肉组织学特性与畜禽肉品质的关系。     

北京黑猪的肉质特性研究

通过对北京黑猪肉的食用品质、营养品质和加工品质等肉质特性的检测分析,考察黑猪肉品质与普通猪肉品质的差异。结果表明：黑猪的肉色a值为5.85±1.63,熟肉率为(75.79±1.85)%,剪切力为(5638±64.20)N;每千克黑猪五花肉中矿物质元素Ca、Mg、Zn、Cu的含量为16.9、85.9、11、0.35mg/kg。饱和脂肪酸(C14:0、C16:0、C18:0和C20:0)总量约占全部脂肪总量的42.24%、油酸占46.64%;背最长肌中必需氨基酸总量(EAA)为9.42g/100g,非必需氨基酸总量(NEAA)为12.82g/100g,氨基酸总量(TAA)为22.23g/100g,EAA/TAA为42.35%,EAA/NEAA为73.46%。黑猪肉色较普通猪肉稍红,具有较高熟肉率,剪切力大小适中,含有多种矿物质元素和维生素,氨基酸和脂肪酸含量丰富,营养较为均衡,是具有重要开发价值的肉类品种。     

Shelf-life of Algin/Calcium Restructured Turkey Products Held under Aerobic and Anaerobic Conditions

The shelf-life of restructured products made with ground turkey or turkey breast pieces and formulated with combinations of 0.5–1.0% sodium alginate, 0.1–0.2% calcium carbonate and 0.15–0.30% lactate (ACL) was compared to product containing a combination of 1.4% NaCl and 0.32% sodium tripolyphosphate and to no-additive controls stored at 4°C under aerobic and anaerobic conditions. No significant (p > 0.05) differences were observed between ACL and salt/phosphate restructured turkey products in the rate and extent of growth of psychrotrophs or lactic acid bacteria. The salt/phosphate combination, however, repressed (p<0.05) the growth of pseudomonads. Overall, inclusion of ACL did not influence spoilage of restructured turkey meat products held under aerobic or anaerobic conditions.     

Quality Characteristics of Hydrocolloid-added Oven-Roasted Turkey Breasts

Oven-roasted turkey breasts were manufactured with 70% added brine to increase yield. The brine contained salt, phosphate, and various combinations of κ-carrageenan, starch, and nonfat dry milk and was incorporated into the breasts by injecting and vacuum tumbling. After stuffing into casings, the breasts were cooked at 72°C, and then cooled to 4°C. Incorporation of 0.5%κ-carrageenan increased yield, improved visual appearance, sliceability, and rigidity and decreased expressible juice compared with the control product. Addition of 1% starch increased yield, but did not increase rigidity. The brine-added products were rated acceptable by a sensory panel.     

Effect of Fragmentation Method and Formulation on the Quality of Patties Made from Restructured Spent Layer Meat

Poultry patties were prepared from spent layer meat fragmented by flake cutting or grinding (0.64 cm and 2.54 cm openings). The formulation consisted of either 100% breast meat, 50–50 breast and leg meat combination or 100% leg meat. Acceptability scores for both flavor and texture were highest for breast meat patties and lowest for leg meat patties. TBA (2-thiobarbituric acid) values showed increases for all treatments at all storage periods. Water-holding capacity (WHC) was highest for breast meat patties. Shear and resistance-to-tear (RTT) values showed that flaked-cut breast meat patties had the lowest shear values but the highest level of cohesiveness. The coarsely ground patties had higher shear values and lower RTT values.     

Prediction of Pork and Lamb Meat Quality Characteristics

A two-factor central composite rotatable design and corresponding response surface analysis were successfully applied to data from pork and lamb loin roasts, using cooking temperature and endpoint temperature as the two independent variables. Heating rate (°C/min), evaporation loss, cooking time, total moisture, and chromaticity coordinate (z) were found to be significantly affected (p ≤ 0.10) by different combinations of cooking temperatures and endpoint temperatures in pork and lamb. Additional significant variables for pork were total nitrogen, remaining protein fraction and sensory panel juiciness; and for lamb, heating rate (°C/g), drip loss, total cooking loss, expressible moisture index, total nitrogen, chromaticity coordinate (×), saturation index, and sensory panel doneness and color. Response surfaces were useful in evaluating results.     

牦牛肉品质特性研究进展

牦牛肉品质特性是实现牦牛肉高价值的基础,本文综述近年来对牦牛肉品质的相关研究,从营养品质、食用品质、加工品质及卫生品质等几方面做系统综述,说明牦牛肉具有营养丰富、安全无污染等特点,但食用品质略次于普通牛肉（因人的喜好而异）。     

重组肉加工中黏合剂的应用及研究进展

肉的重组技术是指将低成本的小块碎肉整合起来,从而提高产品的品质和价值。黏合剂在重组肉制品中起主要作用,其原理是可以形成三维网状结构,这种结构可以阻止肉制品中的风味、营养及水分的流失。黏合计也可以作为重组肉制品中水分和脂肪的乳化剂。本文主要介绍了近几年不同种黏合剂(如海藻酸钙盐、转谷氨酰胺酶、纤维蛋白原、食用胶等)在重组肉中的应用原理及研究进展,以其为后续研究提供理论依据。     

牦牛肉品质特性研究进展

牦牛肉是我国青藏高原的重要畜牧产品之一,在当地居民的膳食及高原地区的经济发展中占据重要地位。了解牦牛肉的肉质特性对于牦牛肉的精深加工和牦牛资源的合理开发有重要意义。本文综合近几年国内外相关研究,从营养品质、食用品质和加工品质3个方面对牦牛肉的品质特性进行概述和分析,以期为牦牛肉的品质改善和产品开发提供参考和思路。牦牛肉营养价值高、绿色无污染、市场潜力大,但嫩度较差,今后需借助适当饲养方式和宰后处理方式对其嫩度进行改善。     

Effect of Calcium Carbonate and Sodium Alginate on the Textural Characteristics, Color and Color Stability of Restructured Pork Chops

The effects of factorial combinations of calcium carbonate (0.00 and 0.26%) and sodium alginate (0.0 and 0.7%) on the initial cooked tensile strength and texture profile analysis and the amount of discoloration during three months frozen storage of restructured pork chops were investigated. Calcium carbonate increased (p < 0.05) and alginate had no effect (p>0.05) on the tensile strength of the chops. Alginate decreased the hardness, cohesiveness, springiness, chewiness and gumminess of the restructured chops (p < 0.05). Chops that contained alginate and/or calcium carbonate had more initial discoloration than those that contained (1) no additives, (2) 0.75% NaCl plus 0.5% sodium tripolyphosphate, and (3) 0.75% NaCl plus 0.26% calcium carbonate but they did not discolor further during frozen storage.     

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%。     

复合磷酸盐添加量对调理重组牛肉品质特性的影响

本试验在调理重组牛肉制品中添加不同浓度的复合磷酸盐,探究产品水分迁移、黏结强度、色差、p H值等指标的变化,进而说明复合磷酸盐的添加量对调理重组牛肉制品品质特性的影响。结果表明随着复合磷酸盐添加量的增加,黏结强度、p H值和出品率显著升高(P0.05),解冻损失显著降低(P0.05)。并且结合低场核磁研究发现,拟合后的T_2弛豫时间主要分布为3个峰,其中,T_(2b)、T_(21)随复合磷酸盐添加量的增加向快的弛豫方向移动,当复合磷酸盐添加量为0.3%时,弛豫时间最短,说明此时结合水和不易流动水与肌肉蛋白的结合最紧密;且此时产品的感官评价各项指标均达到最佳。     

优质鸡肉质性状相互关系的研究

本试验研究了优质鸡胸肌和腿肌肌肉性状间的相互关系,并对肉质性状进行了主成分分析。结果表明,肌肉IMF与pH1、pH2、肌纤维密度呈正相关,而与烹饪损失、肌肉剪切力、肌纤维直径呈负相关。肌肉pH与烹饪损失、剪切力、肌纤维直径呈负相关,而与肌纤维密度呈极显著正相关。滴水损失与烹饪损失、肌纤维密度呈负相关,而与剪切力、肌纤维直径呈正相关。肌肉烹饪损失、剪切力与肌纤维直径呈正相关,而与肌纤维密度呈显著负相关。另外,主成分分析表明,胸肌肉质性状可以用4个主成分因子进行表示,腿肌肉质性状可以用2个主成分因子进行表示。     

Production of Restructured Meat using Microbial Transglutaminase without Salt or Cooking

To produce restructured meat, microbial transglutaminase (MTGase) was evaluated for its ability to introduce covalent crosslinks between protein molecules. Pork muscle cubes were mixed with MTGase and held at 5°C for 2 hr for the enzyme reaction. Restructured products were analyzed for binding strength without cooking. MTGase treatment resulted in effective binding of meat pieces provided there was addition of salt (NaCl). To ensure proper binding without NaCl, some food proteins with MTGase were also investigated. Meat cubes in combination with MTGase and sodium caseinate showed acceptable bind, and sodium caseinate appeared to be a superior substrate for the crosslinking to meat proteins than soy protein, whey protein, or gelatin. These results suggest a useful method for producing restructured meat which can be distributed in the raw, chilled state.     

食盐对调理重组牛肉制品品质及水分分布特性的影响

为探讨不同食盐添加量(0%、0.5%、1.0%、1.5%、2.0%和2.5%)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,研究不同食盐添加量对产品的质构特性、黏结强度、色差、水分活度、弛豫时间以及肌肉微观结构的变化。结果表明,随着食盐添加量的增加,调理重组牛肉制品的水分活度显著降低,黏结强度显著增强,产品的质构特性得到显著改善(P0.05),但是色泽变暗。另外,低场核磁共振分析发现,增加食盐的添加量,不易流动水含量逐渐增多,自由水含量逐渐减少,产品的保水性逐渐增强。扫描电子显微镜结果显示,增加食盐的添加量可以使肉块黏结处的三维网络结构越来越致密,提高了产品的保水性和黏结强度。对产品进行感官评价表明,当食盐添加量为1.5%时,产品品质最好,咸味适中。综合考虑产品品质和感官品质,确定在调理重组牛肉制品中食盐的最佳添加量为1.5%。