Composition and Structure of Fat Globule Surface Layers in Recombined Milk

Protein coverage, composition and structure of surface layers of fat globules in recombined milk were determined. Average protein load was ～6 mg/m² fat surface. Both casein and whey proteins were present in the fat globule surface layer, with casein adsorbed in preference to whey proteins and α_s (α_sl+α_s2)-casein adsorbed in preference to β-casein. Transmission electron microscopy showed that the surface layer of fat globule was made up of casein micelles, fragments of casein micelles and a thin layer of protein, possibly whey proteins. Experiments with surface layers that had been dispersed in EDTA showed that the extent of dissociation of caseins followed the order: β-casein > α_s-casein ≦ K-casein, suggesting that most of the K-casein was probably associated directly with the fat surface.     

EFFECT OF DIFFERENT FATS ON THE QUALITY OF GOAT MEAT PATTIES INCORPORATED WITH FULL-FAT SOY PASTE

Effect of different fats such as goat fat, chicken fat, combination of goat and chicken fat and refined mustard oil (RMO) were evaluated in goat meat patties (GMPs). Patties with 10% RMO contributed significantly ( P <  0.05) better emulsion stability compared with others. There were no significant effects of different fats on physicochemical and textural attributes of patties. Patties with RMO had significantly ( P <  0.05) lower cholesterol content than other groups. GMPs with RMO, chicken fat and chicken and goat fat combination rated higher for all sensory attributes than patties with goat fat, which had significantly ( P <  0.05) higher mouth coating and lower overall acceptability. Flavor and overall acceptability were higher in patties with chicken fat. Histological study showed improper dispersion of goat fat in continuous phase of meat protein matrix (emulsion) compared with others .

PRACTICAL APPLICATIONS

Utilization of hard fats from goat, sheep and buffalo in emulsion-based meat products decreases emulsion stability because of its poor dispersibility, and consequently its cooking yield. Goat fat also contributes to a smeary and greasy mouth-coating problem and reduces the palatability of meat products. Alternatively, chicken fat disperses well in meat emulsion because of its high unsaturation and enhances the flavor of the products. However, the efficient utilization of goat fat is essential to support an economical goat meat production system and for developing meat products. The present study showed successful utilization of goat fat when combined with chicken fat, and the products had similar sensory attributes and acceptability as in meat products with chicken fat and refined mustard oil. This study would also help in better use of excess fat from spent hens in other meat products.     

Modelling of post-rain attenuation of microwaves at 22·235 GHz in relation to vertical transport of water vapour

Abstract

Attenuation of microwaves (up to 30 GHz) around the water vapour absorption line on 22·235 GHz tends to persist even after the stoppage of rain during the monsoon season. A theoretical model has been developed for the post-rain residual absorption of radio waves at 22·235 GHz (λ = 1·349 cm) by considering the vertical transport of water vapour in the region of the rain event. The theoretical estimate agrees fairly well with that obtained experimentally during different post-rain events, recorded by a radiometer, operating at the Institute of Radio Physics and Electronics, Calcutta University on a round-the-clock basis.     

Spectral emittance measurements of micro/nanostructures in energy conversion: a review

Micro/nanostructures play a key role in tuning the radiative properties of materials and have been applied to high-temperature energy conversion systems for improved performance. Among the various radiative properties, spectral emittance is of integral importance for the design and analysis of materials that function as radiative absorbers or emitters. This paper presents an overview of the spectral emittance measurement techniques using both the direct and indirect methods. Besides, several micro/nanostructures are also introduced, and a special emphasis is placed on the emissometers developed for characterizing engineered micro/nanostructures in high-temperature applications (e.g., solar energy conversion and thermophotovoltaic devices). In addition, both experimental facilities and measured results for different materials are summarized. Furthermore, future prospects in developing instrumentation and micro/nanostructured surfaces for practical applications are also outlined. This paper provides a comprehensive source of information for the application of micro/nanostructures in high-temperature energy conversion engineering.     

Voltage-current characteristics and power relation in arc plasma in a transverse magnetic field †

The variation of current and the corresponding voltage across a mercury are plasma in a varying transverse magnetic field (0 to 3000 g) has been measured for various initial discharge currents. The current gradually decreases and the voltage across the arc increases with the increase of the magnetic field, the power consumed gradually increases and, attaining a maximum value at a certain value of the magnetic field which is different for different initial currents, gradually decreases with the further increase of the magnetic field. Assuming Beckman's expression (1948) for the axial field and the electron density distribution in a transverse magnetic field and Langmuir's expression (1925) for the current in the are plasma, the observed variation of current and voltage can be satisfactorily explained. A theoretical expression has been derived for the magnetic field at which the power consumed becomes a maximum, by assuming the above deductions and also taking into consideration the variation of electron temperature with magnetic field. The value of the magnetic field thus calculated agrees fairly well with the experimental results, especially for low values of initial currents, and the discrepancy for higher currents has been attributed to the limitations of the above deductions for higher values of H/P