Effect of temperature and chemical composition on processed cheese apparent viscosity

Postprandial Glycemic Response to Whole Fruit versus Blended Fruit in Healthy, Young Adults

While increased intake of dietary fiber is known to reduce postprandial glycemic response, it is less understood whether the disruption of dietary fiber, in a blender, alters the postprandial glycemic response. We compared the postprandial glycemic response in 20 young, healthy college students (12 female, 8 male) after consuming whole fruit vs. blended fruit. The fruit included gala apple, with the seeds removed, and blackberries. We used a repeated measures two-way ANOVA with fruit treatment as the within-subject variable, sex as the between-subjects factor, and glucose maximum, glucose incremental area under the curve (iAUC), and 60 min glucose as dependent variables. Glucose maximum and glucose iAUC were significantly lower (p < 0.05) in blended fruit compared to whole fruit and 60 min glucose was marginally significantly lower (p = 0.057) in blended fruit compared to whole fruit. Sex was not a significant main effect and sex*treatment was not a significant interaction for any of the dependent variables. We hypothesize that a reduced glycemic response in blended apple and blackberries compared to whole apple and blackberries might be associated with the release of dietary fiber and nutritive components from ground blackberry seeds.

Effects of different combinations of probiotics on rheology, microstructure, and moisture distribution of soy materials-based yogurt

The effects of different probiotics on the texture, rheological properties, microstructure, and water distribution of yogurt fermented with soy powder, soy isolate protein powder, soy umbilical powder, and soy whey as the main raw materials were studied. The soy materials-based yogurt fermented by Danisco mixed probiotic reached the end of fermentation after 4 h, which significantly shortened the fermentation time compared with other probiotic combinations. The fermentation with Danisco mixed probiotic and Kefir mixed probiotic respectively resulted in good texture and a denser and more homogeneous microstructure, which was consistent with the sensory evaluation results. Both fermentations had a high water holding capacity of 90.92% and 78.30%, respectively, in agreement with the results of moisture distribution tests. However, the elastic and viscous behaviors were weaker at certain shear frequency. This study achieved a high value-added utilization of soy whey and the development of a new soy materials-based yogurt that met the consumption needs of people with lactose intolerance and high cholesterol. PRACTICAL APPLICATION: In this study, high value-added utilization of soy whey was realized, which solved the problems of resource waste and environmental pollution. Meanwhile, the research and development of soy materials-based yogurt provided another nutritional and healthy consumption demand for lactose intolerant people.

An evolving view on food viscosity regulating gastric emptying

Viscosity is a property of most foods. The consumption of the high-viscosity food is associated with a variety of physiological responses, one of which is their ability to regulate gastric emptying and modulate postprandial glycemic response. Gastric emptying has been proven to be a key step affecting the digestion and absorption of food, whereas, the relationship between viscosity and gastric emptying is still far away from being understood. Here, we reviewed the factors that influence food viscosity and food viscosity changes during digestion. Besides, the effect of food viscosity on gastric emptying and food-viscosity-physiological response were highlighted. Finally, "quantitative relationship" of viscosity and gastric emptying was discussed. This review can contribute to the understanding that how food viscosity affects gastric emptying, and help for developing foods that could control satiety and manage body weight for the specific populations.

Direct acidification of requeijão cremoso model by lactobionic acid: physical, chemical and antimicrobial effects

Abstract

Lactobionic acid (LBA) shows singular properties (antioxidant and antimicrobial). However, few studies aim to test them in foods and confirm the actual occurrence of properties. The present study aims to apply LBA/lactic acid in the production of requeijão cremoso model in order to recognize some of the effects caused by the component as a food additive. The effects on the requeijão cremoso model were evaluated by the final properties of the product: water activity, rheological properties, antioxidant and antimicrobial capacity. Model of requeijão completely acidified with LBA showed the maximum antioxidant activity (88%). The results revealed a potential of application of LBA for microbial inhibition. All model produced presented pseudo plastic behaviour.

Graphic abstract

Biomechanical factors in three-dimensional tissue bioprinting

3D bioprinting techniques have shown great promise in various fields of tissue engineering and regenerative medicine. Yet, creating a tissue construct that faithfully represents the tightly regulated composition, microenvironment, and function of native tissues is still challenging. Among various factors, biomechanics of bioprinting processes play fundamental roles in determining the ultimate outcome of manufactured constructs. This review provides a comprehensive and detailed overview on various biomechanical factors involved in tissue bioprinting, including those involved in pre, during, and post printing procedures. In preprinting processes, factors including viscosity, osmotic pressure, and injectability are reviewed and their influence on cell behavior during the bioink preparation is discussed, providing a basic guidance for the selection and optimization of bioinks. In during bioprinting processes, we review the key characteristics that determine the success of tissue manufacturing, including the rheological properties and surface tension of the bioink, printing flow rate control, process-induced mechanical forces, and the in situ cross-linking mechanisms. Advanced bioprinting techniques, including embedded and multi-material printing, are explored. For post printing steps, general techniques and equipment that are used for characterizing the biomechanical properties of printed tissue constructs are reviewed. Furthermore, the biomechanical interactions between printed constructs and various tissue/cell types are elaborated for both in vitro and in vivo applications. The review is concluded with an outlook regarding the significance of biomechanical processes in tissue bioprinting, presenting future directions to address some of the key challenges faced by the bioprinting community.

Relationships among rheological, sensory, and wear behaviors of cheeses

Studying rheological and sensory behaviors of cheese provides structural and texture-related information that could be useful for a better understanding of the complex wear behaviors of cheese and their relationships with cheese industrial and oral processing behaviors. Thus, the objective of this study was to determine the relationships of rheological and sensory properties with cheese wear. Rheological tests including large amplitude oscillatory shear, strain sweeps at different temperatures (5, 15, and 25°C), and large-strain compression at room temperature (22 ± 2°C) were conducted for cheeses with varying fat contents (40, 50, 52, and 54% fat-in-dry-matter aged for different periods (15, 30, 45, and 60 d). Descriptive sensory analysis was used to evaluate cheese sensory texture attributes. Overall, fat content, testing temperature, and aging time had significant impact on cheese viscoelastic parameters. Higher temperature, aging time, and fat content led to lower rigidity and greater extent of nonlinear viscoelastic behaviors in the cheeses. Mass loss showed negative correlations with critical strain (γ_c ), critical stress (σ_c ), complex modulus (G^* ), and fracture stress, but had positive correlations with phase angle (δ) and fracture strain. Sensory data showed that texture attributes were affected by cheese fat content and aging time and had significant correlations with mass loss at high normal force and sliding speed. This study showed that rheology and sensory data can be used to provide fundamental information on the wear behaviors of cheese and other soft materials.

Effect of Storage Conditions on Apparent Viscosity of Oleogel Developed by β-Sitosterol and Lecithin with Sunflower Oil

The influence of storage conditions on apparent viscosity of mixtures of β-sitosterol and lecithin in sunflower oil was studied using rheology. The results showed the apparent viscosity of oleogel decreased with the increase of the speed of shear and storage temperature, while incresed with prolong of time in experiment conditions. The β-sitosterol and lecithin ratio also affected the apparent viscosity; solutions with ratio (70 β-sitosterol-30 lecithin) performed the highest apparent viscosity. What’s more, all the samples were pseudoplastic fluid. The apparent viscosity of the oleogel depends on storage temperature, storage time and organogelator ratios.

Potentially synbiotic fermented beverage with aqueous extracts of quinoa (Chenopodium quinoa Willd) and soy

The aim of this study was to develop a potentially synbiotic beverage fermented with Lactobacillus casei LC-1 based on aqueous extracts of soy and quinoa with added fructooligosaccharides (FOS). Five formulations with differing proportions of soy and quinoa extracts were tested. The viability of the microorganism, the pH, and the acidity of all formulations were monitored until the 28th day of storage at 5 ℃. The chemical composition of the extracts and beverages and the rheological and sensory properties of the final products were analyzed. Although an increase in acidity and a decrease in pH were observed during the 28 days of storage, the viability of the probiotic microorganism was maintained at 108 CFU·mL−1 in all formulated beverages throughout the storage period. An increase in viscosity and consistency in the formulations with higher concentrations of quinoa (F1 and F2) was observed. Formulation F4 (70% soy and 30% quinoa extracts) showed the least hysteresis. Formulations F4 and F5 (100% soy extract) had the best sensory acceptance while F4 resulted in the highest intention to purchase from a group of 80 volunteers. For chemical composition, F3 (50% soy and 50% quinoa extracts) and F4 showed the best results compared to similar fermented beverages. The formulation F4 was considered the best beverage overall.

Effect of the type of emulsifying salt on microstructure and rheological properties of "requeijão cremoso" processed cheese spreads

The role of different types of emulsifying salts-sodium citrate (TSC), sodium hexametaphosphate (SHMP), sodium tripolyphosphate (STPP) and tetrasodium pyrophosphate (TSPP)-on microstructure and rheology of "requeijão cremoso" processed cheese was determined. The cheeses manufactured with TSC, TSPP, and STPP behaved like concentrated solutions, while the cheese manufactured with SHMP exhibited weak gel behavior and the lowest values for the phase angle (G"/G'). This means that SHMP cheese had the protein network with the largest amount of molecular interactions, which can be explained by its highest degree of fat emulsification. Rotational viscometry indicated that all the spreadable cheeses behaved like pseudoplastic fluids. The cheeses made with SHMP and TSPP presented low values for the flow behavior index, meaning that viscosity was more dependent on shear rate. Regarding the consistency index, TSPP cheese showed the highest value, which could be attributed to the combined effect of its high pH and homogeneous fat particle size distribution.