• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Palatability control points for grass-fed beef: Revealing the key compounds contributing to beef flavor or off-flavor.
【24h】

Palatability control points for grass-fed beef: Revealing the key compounds contributing to beef flavor or off-flavor.

机译：草食牛肉的适口性控制要点：揭示造成牛肉风味或异味的关键化合物。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Due to the variety of cattle breeds, finishing end point, grass quality, and postmortem management, the quality of grass-fed beef is criticized as inconsistent. To improve the eating quality of grass-fed beef, this dissertation focused on investigating (i) the impact of long chain ω-3 fatty acids on beef palatability; (ii) fatty acid composition of different fat depots; and (iii) the impact of diet and aging on beef palatability, fatty acid composition, and aroma-active compounds contributing to beef flavor and off-flavor associated with grass-feeding systems. The results indicated that ground beef flavor decreased linearly (P < 0.001) with increasing levels of eicosapentaenoic acid (EPA; C20:5n3) and docosahexaenoic acid (DHA; C22:6n3) and that offaroma and off-flavor increased linearly and then plateaued ( P < 0.0001) with increasing levels of EPA. Finishing diet (70 vs. 85 % concentrate) had little impact on Jersey beef palatability. However, increased concentrate level decreased polyunsaturated fatty acids (PUFA) in muscle and increased trans fatty acids in all fat depots (P < 0.05). In addition, monounsaturated fatty acid: saturated fatty acid (MUFA: SFA) ratio was the highest in subcutaneous fat, moderate in muscle and seam fat, and the lowest in kidney, pelvic and heart fat (KPH) and visceral fat (VIS). The PUFA: SFA ratio was the highest in muscle, moderate in subcutaneous and seam fat, and the lowest in KPH and VIS. When comparing Feedlot, TR (triticale and annual ryegrass) and Pasture (fescue, brome, clover and orchard grass) dietary treatments, pasture-feeding had negative impacts on beef palatability. Cooked Feedlot beef steaks had higher percentages of C14:0 and C16:0 and lower percentages of c-9, t-11 CLA and trans fatty acids than pasture-raised steaks. Pentanal was higher in pasture-raised ground beef and nonanal was higher in TR beef compared to Feedlot beef. In addition, wet aging decreased ground beef intensity and increased off-flavor of ground beef. Aging improved the tenderness of beef steaks and increased the concentrations of 1-pentanol, 1-hexanol, and 1-octen-3-ol in ground beef. The results of this dissertation will provide valuable information to grass-fed beef producers to improve their management and eventually product quality.;Keywords: Grass-fed beef; Aging; Palatability; Fatty acids; Aroma-active compounds.
机译：由于牛的品种繁多，终点，草的质量和死后管理的关系，人们批评草饲牛肉的质量不一致。为了提高草食牛肉的食用质量，本论文着重研究（i）长链ω-3脂肪酸对牛肉适口性的影响； （ii）不同脂肪库的脂肪酸组成； （iii）饮食和衰老对牛肉适口性，脂肪酸组成和芳香活性化合物的影响，这些成分会导致与草饲系统相关的牛肉风味和异味。结果表明，随着二十碳五烯酸（EPA; C20：5n3）和二十二碳六烯酸（DHA; C22：6n3）含量的增加，牛肉碎的风味呈线性下降（P <0.001），而法玛和异味呈线性上升然后趋于稳定（P <0.001）。 P <0.0001），同时增加EPA含量。最终饮食（70％对85％的浓缩汁）对泽西牛肉的适口性影响很小。然而，增加的浓缩水平降低了肌肉中的多不饱和脂肪酸（PUFA），并增加了所有脂肪库中的反式脂肪酸（P <0.05）。此外，皮下脂肪中单不饱和脂肪酸：饱和脂肪酸（MUFA：SFA）的比例最高，肌肉和接缝脂肪中的比例最高，肾脏，骨盆和心脏脂肪（KPH）和内脏脂肪（VIS）的最低。 PUFA：SFA比值在肌肉中最高，在皮下脂肪和接缝脂肪中中等，在KPH和VIS中最低。当比较饲喂场，TR（黑麦和一年生黑麦草）和牧场（羊茅，bro，三叶草和果园草）的饮食处理时，牧场饲喂对牛肉的适口性有负面影响。与牧场饲养的牛排相比，熟食肥牛牛排的C14：0和C16：0百分比更高，而c-9，t-11 CLA和反式脂肪酸的百分比更低。与肥育牛肉相比，牧草碎牛肉中的戊醛更高，TR牛肉中的壬醛更高。另外，湿老化降低了绞碎牛肉的强度并增加了绞碎牛肉的异味。老化改善了牛肉牛排的嫩度，并增加了碎牛肉中1-戊醇，1-己醇和1-辛烯-3-醇的浓度。本文的结果将为草食牛肉生产者提供有价值的信息，以改善他们的管理并最终改善产品质量。老化;适口性脂肪酸;芳香活性化合物。

著录项

  • 作者

    Jiang, Ting.;

  • 作者单位

    Washington State University.;

  • 授予单位 Washington State University.;
  • 学科 Agriculture Animal Culture and Nutrition.
  • 学位 Ph.D.
  • 年度 2011
  • 页码 175 p.
  • 总页数 175
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号