摘要:

ABSTRACTThe jaggedness of the stress‐strain relationship of two kinds of puffed extrudates stored under different humidity conditions was assessed by the power spectrum of the Fast Fourier Transform and the Natural Fractal dimension of normalized compression curves. Both analyses, performed with a micro‐computer, provided a consistent measure of jaggedness. The apparent Fractal dimension, obtained using the Blanket algorithm, was the most convenient measure of overall ruggedness since it was expressed by a single number. The power spectrum that resulted from the Fourier transform, however, could be used to identify the length scale of structural features where fracture takes place, and its shape could be more directly related to structural features and textural propert

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05461.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTThe influence of different acids on the aerobic growth kinetics ofAeromonas hydrophilawas studied in BHI broth with 0.5 and 2.0% NaCl incubated at 5 and 19°C. Growth curve data were analyzed by the Gompertz equation and a nonlinear regression program; generation and lag times were calculated from the Gompertz parameters. Type of acid, pH, NaCl level and temperature influenced lag and generation times. The organic acids (acetic, lactic, citric and tartaric) inhibited growth at higher pH values than inorganic acids (HCl and H2SO4). The high NaCl level interacted with type of acid and pH to restrict growth of the organism at the lower temperature of incubation. Acetic and lactic acids were effective in controlling the growth ofA. hydrophilaand could readily be combined with low holding temperature to render foods free of the organism

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05462.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTA screening analysis was performed to determine the influence of independent parameters (18) on thawing times of frozen spherical (prolate and oblate) and finitely cylindrical foods using a computerized simulation procedure assuming food volume shrinkage from density changes and temperature dependent physical properties. Of 18 independent parameters, 6 were significant for both foods: thawing medium temperature, initial freezing point, Biot number, radiative heat exchange, a parameter for effective specific heat and shape factor (nonsignificant influence of volumetric changes). Predictive regression equations were developed for estimating thawing time as function of significant parameters. Predictive equations were validated experimentally. A sensitivity analysis showed errors in thawing time were influenced most strongly by food dimensions, followed by operational temperatures, thermophysical properties and convective surface heat‐transfer coefficien

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05463.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTAn enzyme which converts the citrus by‐product limonene to α‐terpineol was purified 13‐fold. After cell disruption ofP. gladioli, α‐terpineol dehydratase (α‐TD) remained associated with a heterogeneous group of particulate material. α‐TD was partially solubilized by extraction with 10 mM HEPES buffer, pH 7.0 containing 2.0% (w/v) Triton X‐100 and 0.5M sodium trichloroacetate. Two soluble forms existed in 1.0% (w/v) Triton X‐100 with apparent molecular weights of 94,500

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05464.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTAluminum oxide was used to insolubilize (i.e. to lake) riboflavin 5′‐phosphate (FMN) to improve the light stability of vitamin B2. HPLC was used to determine adsorption percentage and light stabilities of laked FMN. The adsorption of FMN on aluminum oxide was very effective. An FMN content of 55% in lake was achievable, with adsorption of 91%. The adsorption isotherm was of the Langmuir class, and differed from the desorption isotherm. The stabilities of laked FMN at different light intensities and awvalues were significantly (p=0.05) higher than those of free

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05465.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTThe identification of staphylococci and micrococci isolated from an intermediate moisture meat product, basturma, was studied. From the 120 isolates 92.5% were classified as staphylococci and 7.5% as micrococci. The differentiation of the species revealed: 42%Staphylococcus epidermidis, 32%Staphylococcus saprophyticus, 12%Staphylococcus simulans, 4%Staphylococcus carnosus, 2% Staphylococcus hyicussubsp.hyicusand 7.5%Micrococcus varians.

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05466.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTSteaks, fabricated from forequarters from field‐slaughtered Alaskan reindeer, were prepared from meat flaked to two sizes (1.295 and 1.905 cm), with (0.5%) and without phosphate, and with (0.5%) and without salt. Phosphate did not appreciably affect sensory properties. Larger flakes and salt improved quality and acceptability, therefore, additional steaks were fabricated from meat flaked with a larger cutting head (4.064‐cm) and with three levels of salt (0.0, 0.5 and 0.75%). Steaks containing 0.75% salt were less chewy, softer, juicier, and more acceptable than those made with 0.5% salt but did not differ from those containing no salt. Feasibility of producing restructured steaks from reindeer forequarters was demonstra

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05467.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

摘要:

ABSTRACTThe sulfhydryl content of heat‐induced soluble egg white aggregates gradually decreased in proportion to standing time at room temperature, and the molecular size of the aggregates continued to increase at least 4 days. The progress of soluble egg white aggregates was much inhibited by N‐ethylmaleimide. Soluble egg white aggregates are polymerized through a mechanism involving sulfhydryl‐disulfide interchange and sulfhydryl oxidation during sta

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05468.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY

ISSN:0022-1147    

DOI:10.1111/j.1365-2621.1992.tb05410.x

出版商:Blackwell Publishing Ltd    

年代:1992

数据来源: WILEY