Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    International journal of food science & technology 23 (1988), S. 0 
    ISSN: 1365-2621
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: An ultrasonic velocity technique has been compared with pulsed NMR‘weight’ and ‘direct’ methods of determining solid fat contents (SFC). Measurements were made at 18°C using samples 0–20% of rapidly cooled tristearin in paraffin oil, tristearin in sunflower oil and tripalmitin in paraffin oil. Correlations between the amount of triglyceride added and the SFC predicted by each of the techniques were always better than 0.995 (n± 13). The precisions of the ultrasonic technique (0.2%) and the weight method (0.3%) were significantly better than that of the direct method (0.7%). The ultrasonic technique may therefore offer a suitable alternative or adjunct to the established pulsed NMR technique for SFC determinations; it has considerably lower capital cost and a faster sampling rate.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    International journal of food science & technology 22 (1987), S. 0 
    ISSN: 1365-2621
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: The ultrasonic group velocity has been measured through 0–20% mass fraction samples of tristearin, tripalmitin, trilaurin and 1-oleodipalmitin suspended in paraffin oil at 25°C and 1 MHz. For tristearin, tripalmitin and trilaurin there is an increase of about 3.1 m/sec per 1% increase in insoluble triglyceride in suspension. For trilaurin and 1-oleodipalmitin there is a slight decrease in velocity with increasing soluble triglyceride. The technique may, therefore, prove useful for determination of solubilities of triglycerides in suspension, as well as for determining solid fat contents. For the tristearin/paraffin oil suspensions there is a good correlation between the solid content added and that predicted by a theoretical formula available in the literature (correlation = 0.998 for twenty samples). The reproducibility of the solid fat content determination is 0.2%, the accuracy is about 0.6%. The technique is easily automated, cheap, accurate, rapid and non-intrusive and should, therefore, prove useful both as an in-line quality control monitoring device and as a new instrumental technique for research applications.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The ultrasonic velocity within Atlantic cod (Gadus morhua), Atlantic mackerel (Scomber sombrus), Atlantic salmon (Salmo salar), Channel catfish (Ictalurus punctatus), and Sole flounder (Pseudopleuronectes americanus) fillets was measured over a range of temperatures (5 to 35°C) using an ultrasonic pulse-echo technique (∼3.5 MHz). Lipid, protein, moisture and ash content of fillets were determined by standard methods. Ultrasonic velocity-temperature profiles were dependent on fish composition and could be predicted reasonably well using a semi-empirical equation developed in a previous study. Ultrasonic velocity measurements show potential for analyzing fish composition.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 63 (1998), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The ability of Tween 20 and whey protein isolate (WPI) to influence lipid oxidation was investigated by evaluating the effects of emulsifier concentration and physical location on iron-catalyzed oxidation of emulsified Menhaden oil. Addition of Tween 20 or WPI to the aqueous phase of a 0.5 wt% Tween 20 stabilized emulsion increased lipid oxidation as determined by both thiobarbituric acid reactive substances (TBARS) and lipid peroxides. Tween 20 (2.0 wt%) and WPI (0.05–1.0 wt%) combinations inhibited TBARS formation 23–60%. Oxidation of a WPI-stabilized emulsion decreased with decreasing pH (3–7) but in a Tween 20 stabilized emulsion oxidation increased with decreasing pH. The low oxidation rate for the WPI-stabilized emulsion at pH 3 was increased when Tween 20 displaced WPI from the droplet interface. Results indicate that the oxidative stability of emulsifed Menhaden oil could be increased by controlling emulsifier type, location and concentration.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 66 (2001), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: : The influence of droplet flocculation on the optical properties of 1 and 10 wt% oil-in-water emulsions with and without dye was investigated. Flocculation was induced by addition of SDS micelles to the aqueous phase of emulsions to increase the depletion attraction between droplets. Droplet flocculation caused the spectral reflectance and L-value (lightness) of emulsions to decrease, and the magnitude of the a- and b- values to increase, but the changes were rather small. Similar trends were observed for emulsions with and without dye. Overall, emulsion optical properties were dominated by light scattering from droplets rather than flocs.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 64 (1999), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The creaming stability and viscosity of oil-in-water emulsions stabilized by whey protein isolate were monitored as functions of dextran sulfate (DS) and electrolyte (NaCl) concentration. At a specific DS concentration (the critical flocculation concentration, CFC), the droplets became flocculated, which promoted creaming. Addition of electrolyte caused an increase in CFC. At NaCl concentrations 〈0.5 wt%, addition of electrolyte decreased emulsion viscosity, but at concentrations 〉0.5 wt% it caused an increase in viscosity due to increased flocculation. The results were due to the influence of electrostatic screening on the effective volume of DS molecules and colloidal interactions between droplets.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 62 (1997), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Corn oil-in-water emulsions (20 wt%, d32∼ 0.6 μm) stabilized by 2 wt% whey protein isolate were prepared with a range of pH (3–7) and salt concentrations (0–100 mM NaCl), and particle size, rheology and creaming were measured at 30°C. Appreciable droplet flocculation occurred near the isoelectric point of whey protein (pH 4–6), especially at higher NaCl concentrations. Droplet flocculation increased emulsion viscosity and decreased stability to creaming. Results are related to the influence of environmental conditions on electrostatic and other interactions between droplets.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 64 (1999), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Measurements of the velocity of ultrasound through a sample as a function of diffusion distance were used to study molecular diffusion of sugars through biopolymer solutions. A1 wt% xanthan solution was prepared which consisted of a lower layer containing no sucrose, and an upper layer containing sucrose (10, 20, 30, or 40 wt%). The velocity of ultrasound through the biopolymer solutions was measured as a function of sample height and time, and then converted into sucrose concentration-distance profiles using an empirical calibration curve. The translational diffusion coefficient of the sucrose in the upper and lower layers was determined by fitting the experimental data to a Fickian diffusion model. The measured diffusion coefficients were in reasonable agreement with published values for sucrose in aqueous solutions in the absence of xanthan, which suggests the biopolymer had little influence on molecular diffusion.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 67 (2002), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: : Calcium chloride (0 to 10 mM) and potassium chloride (0 to 600 mM) were added into model nutritional beverage emulsions containing 7% (w/w) soybean oil droplets and 0.35% (w/w) whey protein isolate (pH 6.7). The particle size, surface charge, viscosity, and creaming stability of the emulsions then were measured. The surface charge decreased with increasing mineral ion concentration. The particle size, viscosity, and creaming instability of the emulsions increased appreciably above critical CaCl2 (3 mM) and KCl (200 mM) concentrations because of droplet flocculation. The origin of this effect was attributed to reduction of the electrostatic repulsion between droplets due to electrostatic screening and ion binding. CaCl2 promoted emulsion instability more efficiently than KCl because Ca2+ ions are more effective at reducing electrostatic repulsion than K+ ions.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 63 (1998), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: A theoretical model was developed to predict spectral reflectance and color of emulsions from droplet (radius and concentration) and dye (absorption spectra and concentration) characteristics. The Rayleigh-Gans-Debye theory of light scattering was used to calculate the scattering cross-section, absorption cross-section and asymmetry factor of droplets. These values were used to calculate spectral reflectance of an emulsion based on Kubelka-Munk theory. The tristimulus coordinates (L, a, b) of an emulsion were calculated from its spectral reflectance using color matching functions. Predictions were in good agreement with experimental measurements on oil-in-water emulsions containing a red food dye. The theory may be useful for optimization of emulsion appearance.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...