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91.
    

ABSTRACT

Select, Choice and Certified Angus Beef (CAB) strip loin steaks were sold in Lubbock, TX to determine consumer acceptability. A home survey was attached to each package of steaks (return = 191 steak evaluations). Consumers did not detect differences in tenderness or flavor, but rated CAB steaks juicier (P < 0.05) than Select or Choice. However, 68% of CAB consumers rated steaks as extremely or very tender, but less than half rated Choice and Select steaks the same way. Consumer tenderness and flavor scores for Select steaks were more variable, but consumer satisfaction and tenderness acceptability did not differ (P > 0.05) between grades. Trained sensory panelists rated CAB steaks higher (P < 0.05) than Choice or Select for all palatability traits except flavor intensity. Shear force decreased (P < 0.05) by quality grade as CAB steaks sheared with the least resistance. These results showed marbling influenced objective palatability measures and decreased the variation in both objective and consumer measures of palatability.

PRACTICAL APPLICATIONS

Quality grades were established to predict beef palatability, but marbling can be an unreliable predictor of tenderness. Branded beef programs, such as Certified Angus Beef (CAB), have been developed to distinguish higher palatability products and provide more consistent products for consumers. Consumers can distinguish between levels beef tenderness and are willing to pay a premium for tender beef. Moreover, consumers find product consistency is moderately important when purchasing fresh beef. Therefore, the purpose of this study was to determine consumer acceptability based on in‐home evaluations of strip loin steaks from United States Department of Agriculture Select and Choice grades and CAB purchased from a retail supermarket environment.
  相似文献   
92.
    
2,4,6-Trichloroanisole (TCA), which is a major cause of cork taint in bottled wine, is already present in the bark of living cork trees to the extent that it can account for the majority of incidences of cork taint in bottled wine. Other post-harvest sources of TCA are known and may add to the forest-derived TCA in cork. Both the origin of TCA in the bark in the forest, and the means by which additional TCA can accumulate in the corks during manufacture, have been examined. TCA can originate from 2,4,6-trichlorophenol (TCP) produced from naturally-occurring phenol and chlorine from sanitisers and cleaning products, and town water. Also, chlorophenol biocides have accumulated in the environment due to the large quantities used in previous times – TCP has been a minor impurity in pentachlorophenol biocides and a major ingredient in other preparations. There is some evidence that chlorophenols were used in pest management in the forest prior to restrictions on the use of these materials. The factors affecting the uptake and loss of TCA by the bark on the tree and by corks during production, and through to their use in the bottling of wine have been considered in this review.  相似文献   
93.
94.
    
The characteristics of rendered duck fat (RDF) were compared to commercial sources of soybean oil, lard, tallow, butter and olive oil. RDF was highly susceptible to lipid oxidation during storage compared to the other fats and oils. However, 0.005% tert‐butyl hydroquinone delayed the onset of lipid oxidation to an extent that was comparable to the lag phase observed in the commercial fats and oils. Positive attributes of RDF included a relatively high oleic acid content and low saturated fat content. Undesirable attributes of RDF included a lack of conjugated linoleic acid (CLA) and intermediate levels of trans fatty acids (TFA) compared to the other lipid sources. Decreasing the time and temperature of rendering decreased the TFA content in RDF. Around one‐half of the TFA content in RDF was vaccenic acid which is converted to CLA after ingestion.  相似文献   
95.
    
Agar, K‐carrageenan and gellan gels (2%) with and without infused sucrose (5, 10 and 12.5%) were freeze dried and the mechanical and acoustic signatures of the resulting solid sponges recorded. For comparison, agar gels with 5 and 10% starch were also prepared and likewise tested. The presence of the sugar, or starch, in the dried gels increased their density in a manner that could not be predicted from the corresponding stoichiometric relations between the gum and additive indicating that the sugar, or starch, were not inert fillers. In general, the presence of the sucrose in the dried gel solid matrix increased the brittleness of the sponges. The effect could be quantified in terms of the increase in the mechanical signature's apparent fractal dimension (Richardson's and Kolmogorov's). The more brittle dried gels also had a “richer” acoustic signature whose apparent fractal dimension was determined with the “blanket” algorithm. Despite the irregular and jagged appearance of all the dry gels stress‐strain relationships, they could be described by the same kind of a three parameter empirical model originally derived for soft baked products and polymeric foams. Although the added sugar, or starch, stiffened the dehydrated gels the effect could not be quantified unambiguously because of the differences in the density and in the overall shape of the stress‐strain curve.  相似文献   
96.
    
Deuterium-labelled trichloroanisole (d5-TCA) added to the surface of wine corks in bottles did not contaminate wine after more than three years of bottle storage. Most of the added d5-TCA was lost, presumably by evaporation. That remaining was largely confined to the outer portion of the closures. Under the conditions of this study, the cork closures were highly effective barriers to the transmission of exogenous TCA.  相似文献   
97.
    
A knowledge-based navigation system for autonomous land vehicles (ALVs) has been developed which can successfully negotiate an obstacle and threat-laden terrain, even if nothing is known beforehand about the terrain. The ALV stores new information in its memory as it travels, has the ability to backtrack out of unexpected dead ends, and performs spontaneous decision making in the field based on local sensor readings. The optimal global route of the ALV journey is obtained using dynamic programming, and decision making is accomplished via a production rule-based system. Execution examples demonstrate the power of the prototype system to solve navigation problems. This establishes the feasibility of constructing a valid ALV by combining search techniques with artificial intelligence tools such as production rule-based systems.  相似文献   
98.
我国老龄化程度不断提高,家庭结构日趋小型化,在此背景下,养老机构蓬勃发展,价格成为限制老年人选择养老机构的重要原因。通过对北京市养老机构的调研,揭示其价格体系中存在中档养老机构缺乏的结构失衡问题。基于建筑设计视角,采取相关性分析筛选养老机构价格影响因素,主要包含建筑规模、房型组合、机构规模、平均床位面积和接收对象类型,并通过交叉分析对影响价格的机制进行了研究,提出新建中档养老机构的价格控制措施。以完善养老机构价格体系,实现其健康持续发展。  相似文献   
99.
A microporous membrane containing immobilized sulfonic acid moieties was used for the rapid fractionation of the cations lactoperoxidase (LP) and lactoferrin (LF) from whey. The breakthrough curves of LP and LF, the LP activity and LF concentration in the elution peaks for different whey loading volumes, and the stability of membrane performance over repeated cycles of loading and elution were measured. Recovery was unaffected by an 8-fold scale-up exercise and repeated cycling, and was 73–6% for LP and 50–5% for LF. The membrane system was more rapid, smaller in size, and used a higher flow rate than traditional bead-based systems.  相似文献   
100.
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