Food Hydrocolloids最新文献

In the present work, the rheological properties of model boli were analysed based on the granular matter physics. Polysaccharide microgels mixed with artificial saliva were prepared as model boli. The storage modulus G′ of alginate gel beads increased and then decreased with increasing content of artificial saliva. Surface of alginate gel beads prepared by dripping into calcium chloride solution were wiped to remove the moisture to mimic the oral condition of the Sjögren's syndrome. G′ decreased monotonically with increasing artificial saliva beyond a certain amount of the added saliva, which is similar to the widely observed characteristic of wet granular materials. Although the analysis is limited to a model bolus at a certain stage of oral processing mimicked by instrumentally prepared microgels of uniform size and shape, it revealed some fundamental aspects highlighting the implication of a wet granular matter as a useful concept for further understanding of the bolus rheology.

In this study, κ-carrageenan was chemically modified by acid anhydride esterification to produce acid anhydride-esterified κ-carrageenan, and its properties were subsequently determined. Acid anhydride-esterified κ-carrageenan can improve the water retention properties of gels and limit the deterioration of gel textural performances during the freezing process. Scanning electron microscopy results before and after freezing showed that the frozen esterified κ-carrageenans had a more regular and less fibrous network structure, which suggests that the esterified κ-carrageenans better maintained the gel network structure. These phenomena were studied in relation to intermolecular forces, water movement, and ice crystal formation. The intermolecular force analysis showed that the esterification of anhydride disrupted the hydrogen bond formed between κ-carrageenan molecules, enhanced hydrophobic interactions among κ-carrageenan molecules, and resulted in stronger electrostatic repulsion. Low-field nuclear magnetic resonance analysis showed that acid anhydride-esterified κ-carrageenan more effectively bound to water molecules during freezing. Differential scanning calorimetry results showed that acid anhydride-esterified κ-carrageenan reduced the amount of freezing water and lowered the eutectic point of the gel. The results showed that hydrogen bonding, electrostatic interactions, and hydrophobic interactions modified the structure of the acid anhydride-esterified κ-carrageenan gel network and its binding to water molecules. This phenomenon allowed acid anhydride-esterified κ-carrageenan to better maintain binding with water molecules during the freezing process, which in turn delayed and reduced the formation of ice crystals and greatly decreased the effect of ice crystals on the structure of the gel network.

In this work, the egg white protein-gallic acid-xanthan gum covalent complexes were used to construct emulsions and oleogels and the effects of different concentrations of the complexes on the properties of emulsions and oleogels were investigated. The results showed that the values of emulsion D[4,3] and ζ-potential decreased with increasing complex concentration, while the emulsion stability index increased. The emulsions exhibited good centrifugal stability against changes in temperature, salt ion concentration and pH value. The emulsions prepared with high concentrations of the complexes (0.6–1.0%, wt) showed good viscoelasticity and gelation properties. The oil binding capacity increased from 75.86% to 98.04% as the concentration of oleogel increased from 0.2% to 0.4% (wt), and all the oleogels exhibited a strong gel network structure (G'>G″). Compared with the bulk oil, the oleogel had a stronger antioxidant capacity, and with increasing the concentration of the complexes, the antioxidant ability of the produced oleogel enhanced. This study may provide a theoretical basis for the preparation of protein-polysaccharide-polyphenol based oleogels and their application as solid fat substitutes in the food industry.

Bigels are a class of soft matter systems with high potential in food industry as fortified ingredient replacers or food analogs. The aim of this work was to develop plant-based bigels using potato protein-based hydrogel and candelilla wax-based oleogel. The potato protein concentration and hydrogel:oleogel ratio effects on bigels production was assessed in terms of textural and rheological properties. The incorporation of curcumin and its bioaccessibility after in vitro digestion was also evaluated. All samples presented an oleogel-in-hydrogel structure arrangement. Increasing the protein concentration led to increased hardness and G*, improving the structure and consistency of bigels. The increase of oleogel fraction altered the distribution of oleogel droplets in the hydrogel matrix, affecting the hardness and the consistency of bigels. Overall, the increase of oleogel fraction and protein concentration allowed forming bigels with stronger mechanical properties and higher thermal resistance. The bigel showed a curcumin's bioaccessibility of 16.3 % and a curcumin's stability of 43.8 %, suggesting that this type of structures is promising for the delivery of bioactive compounds at the colon or for slow release of bioactive compounds. Overall, the results showed the possibility to develop potato protein-based bigels with interesting mechanical, rheological and thermal properties by changing the protein concentration and hydrogel:oleogel ratio, expanding the application of bigels in novel food products with high nutritional value and protein content, namely plant-based products.

Lemon peel cell wall material (CWM) residue obtained after acid pectin extraction can be functionalized into a texturizing ingredient using mechanical treatments such as high-pressure homogenization. The application of CWM as a texturizing ingredient is most likely through a dry powder and thus the stability of its functionality (rheological property) during storage becomes an obvious question. However, studies on the glass transition properties of this CWM residue and it's relation to storage stability are largely lacking. This study aims to first evaluate the potential of two methods, i.e. DSC analysis and combined TMCT-DMTA (thermal mechanical compression test – dynamic mechanical thermal analysis) to measure the Tg and relaxation temperature of lemon peel CWM and subsequently relate the results to the stability of the material's rheological property. The results showed that DSC-based Tg measurements may not be the most appropriate indicator for storage stability of the lemon peel CWM residue, despite being the most commonly used method to explain state transition in materials. On the other hand, the structural relaxation phenomena elucidated by the change in mechanical properties measured by TMCT-DMTA correlated with the results of storage stability of the material. To ensure the stability of the CWM residue, storage should be carried out at conditions (temperature and moisture content) before the onset of tan δ curve change. In conclusion, relaxation phenomena observed through the measurement of mechanical properties, in particular the tan δ curve from DMTA, provides a suitable starting point for inferring the stability of the functionalized CWM residue.

This study explored the effects of different levels of dietary inulin supplementation (0–30 g/kg) on the physicochemical and gel properties of duck myofibrillar protein (MP). The results demonstrated that gel strength and water holding capacity of the gel samples were significantly increased (P < 0.05) by 11.69% and 9.26%, respectively, after the addition of 20 g/kg inulin into the diet. Inulin supplementation facilitated the conversion of free water to immobile water. Moreover, dietary inulin increased rheological properties, solubility, surface hydrophobicity, and Ca²⁺-ATPase activity in MP, while reducing particle size and carbonyl content. Raman spectroscopy revealed an increase in the content of α-helix and hydrogen bonds in MP, promoting the structural stability. A denser gel network structure was observed in the dietary inulin group than that in the control group. These improvements in the physicochemical and gel properties of duck MP are related to the fact that dietary inulin increases the proportion of type I muscle fibers in duck meat. This study provides a novel strategy for improving the gel quality of duck MP and reveals the underlying molecular mechanism of dietary inulin in enhancing duck meat quality.

Increasing concerns among consumers regarding environmental sustainability, religion, health, and food safety have led to increasing prominence of plant-based food products. Aquafaba, a viscous liquid by-product obtained from canned or pressured-cooked chickpea, has gained popularity as a cost-effective egg replacement in gluten-free, vegan, and baked foods. In this study, we applied ethanol precipitation to aqueous chickpea aquafaba, yielding a white powder product (AQE-P). Proton nuclear magnetic resonance spectroscopy (¹H NMR) analysis was employed to determine the molecular weight, carbohydrate profile and composition of foam produced from AQE-P. Results revealed significant variations in the chemical composition of aquafaba produced from different chickpea cultivars. Ethanol precipitation effectively reduced simple sugar (sucrose, galactose, and arabinose) as well as oligosaccharides (stachyose, raffinose, and trehalose) from aqueous aquafaba. AQE-P primarily consisted of water-soluble polysaccharides (24.8%, including soluble fiber and gelatinized soluble starch), protein (35.7%), oligosaccharides (18.4%) and insoluble fiber (21.2%). Notably, AQE-P extracted from both fresh and refrigerated aquafaba (4 °C, 24 h) exhibited improved foaming properties due to its higher protein and polysaccharide content. In conclusion, ethanol precipitation can be a simple, rapid, and feasible technology for chickpea aquafaba processing, yielding a functional powder ingredient, AQE-P. This product has potential as a plant-based emulsifier and foaming agent in various food applications, offering enhanced storage stability, nutritional value, and functionality when compared to aqueous or dried aquafaba.

We conducted an investigation into the foam and interface properties of wheat aqueous phase protein (WAP) along with its ethanol-soluble fraction (ES) and non-ethanol-soluble fraction (NES). The results reveal that the ES component exhibits exceptional foamability at both pH 5 and 7, whereas the NES component demonstrates relatively lower foamability but excels in foam stability at pH 5 and 7. The ES component shows a higher initial surface pressure, indicating stronger surface activity and, consequently, superior foamability. In contrast, the NES component exhibits a faster adsorption rate. The surface dilatational modulus of all three proteins increases over time and with varying frequencies, forming an interface layer primarily characterized by elastic behavior. Notably, the NES component displays heightened sensitivity to oscillations, suggesting its enhanced capacity to form a stable adsorption layer at the interface, thereby contributing to foam stability. Within WAP, the combined interactions of the ES and NES components dictate its foam properties, with the ES component primarily influencing foamability and the NES component playing a more significant role in foam stability. This study offers valuable insights into the intricate behavior of wheat proteins at gas-liquid interfaces, thereby enhancing our comprehension of the formation and stability mechanisms of dough aqueous phase foams.