Rheological behaviour of selected commercially available baby formulas in simulated human digestive system

A variety of formulas are available in the global market for infants (< 12 months old) who do not have access to mother's milk. The rheological properties of four different commercially available infant formulas – newborn, anti-reflux, soy and lactose free – in an in vitro digestive system were investigated. The enzymatic saliva when mixed with the formulas did not influence their viscosity in the mouth possibly due to the short residence time. Systematic measurement (every 15 min) of viscosity during gastrointestinal digestion process revealed a decrease in viscosity as time progressed. The most interesting observation was that the viscosity of the anti-reflux formula was relatively higher compared to the other formulas throughout the simulated gastrointestinal digestion process. The results suggest that viscosity of the infant formula in the stomach may have a role to play in preventing gastroesophageal reflux

3D printing of meat

Three-dimensional printing (3DP) process stands as a developing technology for food manufacturing, which offers the opportunity to design novel food products with improved nutritional value and sensorial profile. This review analyses the potential applications of 3DP technology for meat processing and the elemental aspects affecting the printability and post-processing feasibility of 3D printed meat products. The combination of nutritionally balanced ingredients and novel internal structures may be schemed into a multi-material 3D model that meets special individual needs, such as chewing and swallowing difficulties. Furthermore, a temperature-controlled extruder-type 3D printer built with multi-head system is suggested to suit the required conditions for meat safety and rheological requirements

Effect of alkali treatment on the milled grain surface protein and physicochemical properties of two contrasting rice varieties

A systematic study was conducted to explore the effect of grain surface proteins on the physicochemical properties (pasting, retrogradation and textural quality) of rice. Milled rice grains of two selected glutinous (Thadokkham-8 (TDK8)) and non-glutinous (Doongara (DG)) varieties were treated with different concentrations (0%, 0.004%, 0.02%, 0.04%, and 0.2% w/v) of NaOH solution for 1 h. After surface protein removal, the cooked rice grains showed a significant (P 0.05) effect of alkali treatment was observed on the retrogradation thermal temperatures (T, T, and T), but the amount of retrograded starch (as indicated by reduction in ΔH) was decreased significantly (P < 0.05) in both varieties. These findings suggest a good potential of applying alkali pre-treatments in the processing of rice to alter the hardness and stickiness properties of rice

Effect of shearing-induced lipolysis on foaming properties of milk

BACKGROUND The attraction of cappuccino-style beverages is attributed to the foam layer, as it greatly improves the texture, appearance, and taste of these products. Typical milk has a low concentration of free fatty acids (FFA), but their concentration can increase due to lipolysis during processing and storage, which is detrimental to the foamability and foam stability of milk. There are contradictory results in reported studies concerning the effects of FFA on the foaming properties of milk due to differences in milk sources, methods inducing lipolysis, and methods of creating foam. In this study, the foaming properties and foam structure of milk samples whose lipolysis was induced by ultra-turraxing, homogenisation, and microfluidisation (1.5–3.5 μ-equiv.mL−1 FFA) were investigated. RESULTS Compared with others, microfluidised milk samples had the smallest particle size, lowest absolute zeta potential, and highest surface tension; thus exhibited high foamability and foam stability, and very small and homogeneous air bubbles in foam structure. For all shearing methods, increasing FFA content from 1.5 to 3.5 μ-equiv.mL−1 markedly decreased the surface tension, foamability, and foam stability of milk samples. The FFA level that led to undesirable foam structure was 1.5 μ-equiv.mL−1 for ultra-turraxed milk samples and 2.5 μ-equiv.mL−1 for homogenised and microfluidised ones. CONCLUSION Shearing-induced lipolysis greatly affected the physical properties of milk samples and subsequently their foaming properties and foam structure. At the same FFA level, lipolysis induced by microfluidisation was much less detrimental to the foaming properties of milk than lipolysis induced by ultra-turraxing and homogenisation.Peer reviewe

Effects of malondialdehyde-induced protein modification on water functionality and physicochemical state of fish myofibrillar protein gel

Effects of malondialdehyde (MDA)-induced modification on water distribution in fish myofibrillar proteins (MP) gels were investigated using nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI). The oxidative modifications of MP gels were evaluated by surface hydrophobicity, gel strength, water holding capacity (WHC), scanning electron microscopy (SEM) and SDS-PAGE. Influence of heating procedure on water distribution and functional properties of modified MP gels was also investigated. Results from NMR and MRI indicated that the water functionality was strongly affected by the modification level, which corresponded to the changes of water holding capacity of MP upon MDA modification. Compared with unmodified MP gels, the T relaxation times of modified sample increased significantly, indicating an alteration of water-protein interaction upon MDA-induced modification. The fraction of P declined from 7.66% to 0.15% as the MDA addition increased from 0 to 50 mM. Moreover, the relaxation components T disappeared with the addition of MDA mainly due to enhanced protein flexibility and surface hydrophobicity. Besides, the P (free water) of heated MP samples increased by 5.41 times compared with that of unheated MP samples

Intelligent detection of flavor changes in ginger during microwave vacuum drying based on LF-NMR

Low-field nuclear magnetic resonance (LF-NMR) and electronic nose combined with Gas chromatography mass spectrometry (GC–MS) were used to collect the data of moisture state and volatile substances to predict the flavor change of ginger during drying. An back propagation artificial neural network (BP-ANN) model was established with the input values of LF-NMR parameters and the output values of sensors for different flavor substances obtained from electronic nose. The results showed that fresh ginger contained three water components: bound water (T ), immobilized water (T ) and free water (T ), with the corresponding peak areas of A , A and A , respectively. During drying, the changes of A and A were not significant, while A and A decreased significantly (

Interactions between different forms of bovine lactoferrin and sodium alginate affect the properties of their mixtures

The interactions between different forms (apo-, native- and holo-) of lactoferrin (Lf) and sodium alginate at different ratios in aqueous solution in the pH range of 4-7 were evaluated. Fourier transform infra-red (FTIR) spectra of freeze dried mixtures showed shifts only in the bands arising from the carboxylate groups of alginate relative to physical mixtures; indicating intermolecular interactions involving COO- moieties of alginate. Circular dichroism (CD) spectroscopy showed that Lf retained its tertiary structure in the Lf-alginate mixtures. In the pH range of 4-7, the zeta-potential of Lf-alginate solutions was significantly less negative than that of alginate indicating charge compensation. Native-PAGE results indicated that the extent of binding of Lf by alginate was dependent of the form of Lf with apo-Lf displaying a higher binding affinity. At natural pH, the Lf-alginate mixtures generated higher viscosities than their respective sodium alginate controls indicating the existence of intermolecular interactions between the two components. A mixture of native-Lf and sodium alginate showed the highest increase in the viscosity while increasing level of iron saturation in Lf showed an inverse effect on viscosity. DSC analysis showed that the thermal denaturation temperature of native-and holo-Lf can be enhanced upon interaction with alginate in solution. (C) 2015 Elsevier Ltd. All rights reserved

Encapsulation of gases in powder solid matrices and their applications: A review

Gas encapsulation in solid matrices can be an important means to sequester harmful or greenhouse gases and to store useful gases for their subsequent release for a targeted application. In this review, recent developments, the characteristics and gas adsorption capacity of non-organic and organic solid powder matrices (e.g. activated carbons, carbon nanotubes, zeolites, metal-organic frameworks, and cyclodextrins); and potential applications of their complexes in various fields (energy, environment protection, nano-device production, medicine, and food and agriculture productions) are described

Comparison of ultra high temperature (UHT) stability of high protein milk dispersions prepared from milk protein concentrate (MPC) and conventional low heat skimmed milk powder (SMP)

This study compared the UHT (145 °C for 5 s) stability and fouling behavior of high protein milk dispersions prepared from reconstituted low heat skimmed milk powder (RSMP) and milk protein concentrate powder (RMPC). It was found that RMPC at 10 and 14% protein content was more UHT stable as compared to lower protein content RSMP (3.25, 6.5, 7, 7.5, 8%). Matching the total solids and mineral composition of 7.5-RMPC with 7.5-RSMP by addition of minerals and lactose markedly reduced its UHT stability (UHT run-time reduced to 66 min from >120 min). The RP-HPLC analysis showed increased casein dissociation but similar whey protein aggregation in 7.5-RSMP as compared to 14-RMPC. UHT processing lead to formation of larger particles in case of 7.5-RSMP (1.84 μm D(0.9)) as compared to 14-RMPC (0.23 μm D(0.9)). It was observed that mineral environment affected protein interactions leading to the differences in UHT behavior of RSMP and RMPC

Visualizing the interaction between sodium caseinate and calcium alginate microgel particles

In this study, the pH dependent adsorption of sodium caseinate onto the surface of micron-sized calcium alginate microgel particles (20-80\ua0μm) was evaluated by electrophoretic mobility measurements (ζ-potential), microscopy, protein assay and a protein dye binding method. ζ-potential measurements and protein assay results suggested that protein adsorption occurred due to electrostatic complexation between sodium caseinate and calcium alginate and was pH dependent. Results of protein dye binding method were in agreement with those of protein assay and ζ-potential measurements. Confocal laser scanning and fluorescence microscopy confirmed the presence of protein layer on the surface of alginate microgel particles at pH 3 and 4. Micrographs from transmission electron microscopy revealed a protein coating with a thickness of ∼206-240\ua0nm on the gel particle surfaces