β-Lactoglobulin films with spiral cracks
Publication date: April 2014 Source:Food Structure, Volume 1, Issue 2 Author(s): Ronald Gebhardt , Ieva Petkeviciute We studied spiral crack formation in dried β-lactoglobulin films. The spirals result from simultaneous crack propagation and fragment detachment and the final pattern can be mathematically described by a logarithmic spiral equation. Crack patterns were investigated under different β-lactoglobulin and plasticizer concentrations of the initial solution used for film preparation. Spiral crack patterns occur in films over the entire tested concentration range up to c m =250mg/mL, but disappear when mor...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Structure and antioxidant activity of whey protein isolate conjugated with glucose via the Maillard reaction under dry-heating conditions
Publication date: April 2014 Source:Food Structure, Volume 1, Issue 2 Author(s): Qian Liu , Baohua Kong , Jianchun Han , Changyan Sun , Peijun Li The aim of this study was to investigate the structural characteristics and antioxidant activities of the Maillard reaction products obtained from whey protein isolate (WPI) and glucose (1:1 weight ratio) after dry-heating (60°C and 79% relative humidity) for 0–7d. The results revealed that the color (redness and yellowness), the UV–vis absorption, and the fluorescence intensity increased as the reaction time increased (P <0.05). In addition, marked increases...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Self assembly and rheology of emulsions-mimicking food emulsion rheology
Publication date: April 2014 Source:Food Structure, Volume 1, Issue 2 Author(s): Mohammad Mydul Alam , Suzuka Iemoto , Kenji Aramaki , Eiko Oshimura An investigation has been carried out to understand the microstructure of amino based surfactant (cocoyl glutamic acid, CGT) and viscoelastic properties of emulsions mimicking the food emulsion rheology. The structural modulation of the surfactant aggregates depends on the degree of neutralization, temperature and oil concentration. Phase behaviour of the CGT surfactant system behaves similar to a short chain (C12EO8) (Aramaki & Khalid, 2004) or a long chain (C...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Combined confocal microscopy and large deformation analysis of emulsion filled gels and stirred acid milk gels
Publication date: April 2014 Source:Food Structure, Volume 1, Issue 2 Author(s): A.R. Abhyankar , D.M. Mulvihill , M.A.E. Auty The microstructural breakdown properties of heat-induced whey protein (WP) gels prepared at pH 7.0 or 5.4 and containing emulsified sunflower oil (7%, w/w) were studied using notch propagation tensile testing in combination with dynamic confocal laser scanning microscopy (CLSM). In addition, the microstructural breakdown properties of stirred acid milk gels containing added emulsified oil (0–15%, w/w) or Konjac glucomannan (0.05%, w/w) were studied using compressive rheological deformation...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Structure–function relationships in food emulsions: Improving food quality and sensory perception
Publication date: April 2014 Source:Food Structure, Volume 1, Issue 2 Author(s): Cheryl Chung , David Julian McClements Increasing consumer demand for higher quality, cheaper, more convenient, and healthier emulsion-based products means that the food industry must have a good understanding of the relationship between the structural and functional properties of food emulsions. This review article provides an overview of the relationship between the composition and structural organization of oil-in-water emulsions and their physicochemical (optical, rheological, and stability) and sensory (appearance, texture, flavor, ...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Food oral processing: Some important underpinning principles of eating and sensory perception
Publication date: April 2014 Source:Food Structure, Volume 1, Issue 2 Author(s): Jianshe Chen The oral processing of food is a dynamic process which involves a sequence of highly coordinated oral actions and gives desirable sensory experience. Even though this process is perceived to be routine, its governing principles are highly complicated and are still not fully understood. Based on some recent research findings, this paper reviews current understandings on some important issues associated with eating and sensory perception. The review begins with a short introduction to the background of eating studies. This is f...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Investigating the influence of inulin as a fat substitute in comminuted products using rheology, calorimetric and microscopy techniques
Publication date: Available online 24 June 2014 Source:Food Structure Author(s): Derek F. Keenan , Mark A.E. Auty , Linda Doran , Joseph P. Kerry , Ruth M. Hamill The present manuscript studied the effects of fat substitution with two commercial inulins on the magnetic resonance, rheological, calorimetric and microscopic properties of breakfast sausages. Sausage formulations were evaluated using mixture design (D-optimal). A total of 17 experimental treatments were employed, with each representing a different substitution level for fat. Sausage batters were formulated to contain lean pork shoulder, pork back fat/i...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Effect of churning temperature on water content, rheology, microstructure and stability of butter during four weeks of storage
Publication date: Available online 1 August 2014 Source:Food Structure Author(s): Stine Rønholt , Ann S. Madsen , Jacob J.K. Kirkensgaard , Kell Mortensen , Jes C. Knudsen The effect of churning temperature (10°C vs. 22°C) is evaluated with respect to water content, rheology, microstructure and stability of butter produced using the batch churning method with a temperature ramp of 4°C/min. Using pulsed-nuclear magnetic resonance, an increase in relative solid fat content from 44% to 49.5% was observed when decreasing the churning temperature. Due to lower solid fat content formed upon churning at high temperat...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Microstructure of ethylcellulose oleogels and its relationship to mechanical properties
Publication date: Available online 7 August 2014 Source:Food Structure Author(s): Alexander K. Zetzl , Andrew J. Gravelle , Martin Kurylowicz , John Dutcher , Shai Barbut , Alejandro G. Marangoni Small deformation rheology was used at a controlled strain of 0.05% and frequency from 1 to 100Hz to obtain G′, G″, and tan(δ) values for ethylcellulose oleogels of various compositions. Significant increases in both G′ and G″ were noted in oleogels prepared with 100cP ethylcellulose as compared to 45cP, yet no significant differences in tan(δ) were observed among gels containing the same type of vegetable oil....
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Hydrogen peroxide-induced degradation of type I collagen fibers of tilapia skin
In this study, we examined the changes in the mechanical properties, ultra-microscopic structure, and infrared and X-ray diffraction spectra of tilapia skin collagen fibers undergoing hydrogen peroxide-induced degradation. Our results showed that in the presence of hydrogen peroxide the strength and puncture resistance of fish skin collagen fibers decreased exponentially with respect to heating time. Furthermore, this change in mechanical behavior could be fitted satisfactorily with the exponential function Y =851.0e−0.001x (R 2 =0.996). Scanning electron microscopy showed that there were three stages of degradation of ...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Poultry protein isolate prepared using an acid solubilization/precipitation extraction influences the microstructure, the functionality and the consumer acceptability of a processed meat product
Publication date: Available online 28 August 2014 Source:Food Structure Author(s): Zied Khiari , Zeb Pietrasik , Nicole J. Gaudette , Mirko Betti Poultry protein isolate (PPI), prepared through the isoelectric solubilization/precipitation process, was used as a lean meat substitute in chicken patties. The effect of the substitution level on the physicochemical, microstructural and functional properties as well as the consumer acceptability of the patties was investigated. The addition of PPI did not affect (p >0.05) the moisture and the ash contents but significantly increased the fat and the carbohydrate le...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Insights into the β-carotene distribution in carrot roots
Publication date: Available online 28 September 2014 Source:Food Structure Author(s): A.G. Gonzalvez , D. Martin , K. Slowing , A. Gonzalez Ureña This work reports the carotenoid spatial distribution in orange carrot roots measured by Transmission Resonance Raman Spectroscopy. Raman contour mappings of root cross-sections were measured over the spectral range from 500 to 2500cm−1 as a function of the root radius. The overall β-carotene content reveals a heterogeneous distribution predominantly concentrated in the secondary phloem tissue and periderm. Furthermore, detailed measurements of the ν4 band intensitie...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
Microstructure and lactose crystallization properties in spray dried nanoemulsions
The objective of this study was to characterize lactose crystallization behaviour and microstructure of spray dried nanoemulsions with different fat globule sizes (FGS). Powders of the same composition (57.7% w/w lactose, 12.3% w/w sodium caseinate, 27.7% w/w sunflower oil, and 2.3% w/w water) but different FGS (mean diameters 1100nm and 160nm) prior to spray drying were manufactured. Differences in lactose crystallization were studied using dynamic vapour sorption (DVS) and polarized light microscopy (PLM). Crystallization kinetics was modelled using the Avrami and Yang equations. Results showed that lactose crystallized ...
Source: Food Structure - November 1, 2014 Category: Food Science Source Type: research
