205 research outputs found
Methods of Processing Meats
Newer methods of processing meats along with the development of new meat products will become more and more apparent as the meat industry adapts to the changing life-styles of Americans. The fast-food service industry as well as the hotel, restaurant and institutional trade will become an ever more important market for meat products. Electrical stimulation, massaging/tumbling, restructured steaks, hot-boning and retort pouch packaging represent more recent meat products and processing methods
Relationships Among Calcium-Dependent Protease, Cathepsins B and H, Meat Tenderness and the Response of Muscle to Aging
This study was conducted to compare the relative importance of Ca-dependent protease (CDP) and cathepsins B and H to meat tenderness and changes in tenderness in response to postmortem cooler aging. Charolais bulls (n = 8) and steers (n = 7) were slaughtered at 15 mo of age, and total activities of CDP-I (a protease with neutral pH optimum that requires micromolar amounts of Ca for activity) and cathepsins B and H (lysosomal proteases with acidic pH optima) were determined within 1 h. Shear-force values were obtained after 1, 3, 6, 9 and 14 d of aging. Data were pooled when analysis of variance revealed no differences between bulls and steers. Initial shear force was correlated (r = -.71, P \u3c .l0, n = 7) to CDP-I activity (only seven animals sampled for CDP-I), and the overall change in shear force (d 1 to d 14) was correlated to cathepsin B (r = .59, P \u3c .05, n = 15). Most of the aging response occurred between d 3 and d 6 (41.6%), and changes in shear force during this period were related to total activities of cathepsins B and H (r = .44, .64, respectively, P \u3c .05). Collectively, cathepsins B and H accounted for 35 and 58% of the variation in shear force change between d 1 to d 14 and d 3 to d 6, respectively. These data suggest that CDP-I helps to establish initial (d 1) meat tenderness but that cathepsins B and H are responsible for the tenderization that occurs during aging. By manipulating live animal growth and postmortem handling, it might be possible to control meat tenderness through the actions of these enzyme systems
Some Factors Influencing Ante-Mortem Changes in Muscle: A Brief Review
Ante-mortem changes to muscle microstructure are influenced in many ways. During pre-natal cell differentiation and growth , myoblasts develop and mature into cells with quite different characteristics. Incorporated into the genome of these cells is the ability to synthesize a wide variety of filaments which occupy specific niches within each myofibril. During post-natal development , depending upon the particular precursor cell lines, different fiber types are produced. These are especially important in contributing to the ultimate palatability of meat. In this paper several factors which influence ante-mortem changes to muscle microstructure are discussed. While some of these are better understood than others, all of them , nevertheless, are importan
Utilization Of Goose Muscle In The Preparation Of Meat Rolls
South Dakota produces more domestic geese than any other state in the United States. Marketing of geese is decreasing due to importation of Canadian geese and a decreasing consumer demand. Research is needed to increase goose meat consumption. A large percentage of turkey meat is sold as retail convenience products such as rolls, yet there are virtually no comparable products on the market from goose meat. This study was undertaken to develop and evaluate an acceptable goose roll
Utilization Of Spent Fowl In the Manufacture Of Chicken Restructured Steaks
Each year the poultry industry is faced with a large number of spent laying hens (spent fowl), which are often difficult to market at a reasonable price. If less desirable poultry carcasses such as spent hens could be utilized economically to create desirable new products, there would be considerable incentive to do so. Because of the maturity level of spent hens, their muscles are quite tough and, therefore, products made from them would have to be comminuted. A new method of comminution, called flaking, cleanly cuts frozen muscle into wafer—thin slices which aids in the binding properties upon further processing. The manufacture of restructured steaks involves, first, the flaking of meat and, secondly, the pressing of meat into a particular shape. The resulting product should be tender yet simulate the actual eating quality of a real steak. The objective of this study was to determine the optimum levels of white and dark meat required in the formulation of restructured steaks and to examine the feasibility of adding skin and fat to these products
Fabrication Of Steaks From Spent Hens
Research at SDSU has demonstrated that meat from spent laying hens (spent fowl) can be utilized in the production of fabricated steaks and/or roasts. Previous studies utilized raw meat from carcasses that were manually deboned. Under commercial deboning, meat that has been precooked is more easily separated from the bone. Precooking reduces the ability for meat to hold together or bind in a processed product. Precooked and raw spent fowl muscles were compared as raw material for the production of fabricated steaks. The objective of this research was to produce from precooked spent fowl muscle a palatable restructured product that will withstand handling, cooking and serving
Squeezing of Atoms in a Pulsed Optical Lattice
We study the process of squeezing of an ensemble of cold atoms in a pulsed
optical lattice. The problem is treated both classically and
quantum-mechanically under various thermal conditions. We show that a dramatic
compression of the atomic density near the minima of the optical potential can
be achieved with a proper pulsing of the lattice. Several strategies leading to
the enhanced atomic squeezing are suggested, compared and optimized.Comment: Latex, 9 pages, 10 figures, submitted to PR
Optical properties of metal nanoparticles with no center of inversion symmetry: observation of volume plasmons
We present theoretical and experimental studies of the optical response of
L-shaped silver nanoparticles. The scattering spectrum exhibits several plasmon
resonances that depend sensitively on the polarization of the incident
electromagnetic field. The physical origin of the resonances is traced to
different plasmon phenomena. In particular, a high energy band with unusual
properties is interpreted in terms of volume plasmon oscillations arising from
the asymmetry of a nanoparticle.Comment: 14 pages, 5 figures. Physical Review B, 2007, accepte
Application of Absorbing Boundary Condition to Nuclear Breakup Reactions
Absorbing boundary condition approach to nuclear breakup reactions is
investigated. A key ingredient of the method is an absorbing potential outside
the physical area, which simulates the outgoing boundary condition for
scattered waves. After discretizing the radial variables, the problem results
in a linear algebraic equation with a sparse coefficient matrix, to which
efficient iterative methods can be applicable. No virtual state such as
discretized continuum channel needs to be introduced in the method. Basic
aspects of the method are discussed by considering a nuclear two-body
scattering problem described with an optical potential. We then apply the
method to the breakup reactions of deuterons described in a three-body direct
reaction model. Results employing the absorbing boundary condition are found to
accurately coincide with those of the existing method which utilizes
discretized continuum channels.Comment: 21 pages, 5 figures, RevTeX
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