X-ray microtomography to study the microstructure of cream cheese-type products.

In this work, the imaging x-ray microtomography technique, new to the field of food science, was used for the analysis of fat microstructure and quantification of the fat present in cream cheese-type products. Five different types of commercially produced cheeses, chosen for their variability of texture, were used for this experiment: sample A, sample B, sample C, sample D, and sample E. Appropriate quantitative 3-dimensional parameters describing the fat structure were calculated (e.g., the geometric parameter percentage of fat volume was calculated for each image as a representation of the percentage of total fat content within the sample). The dynamic-mechanical properties of these samples were also studied using a controlled-strain rotational rheometer. Storage modulus and loss modulus were determined in a frequency range of 0.01 to 10 Hz. The strain value was obtained by preliminary strain sweep oscillatory trials to determine the linear viscoelastic region of the cream cheese-type products. Statistical correlation analysis was performed on the results to help identify any microstructural-mechanical structure relationships. The results from this study show that microtomography is a suitable technique for the microstructural analysis of fat in cream cheese-type products, as it does not only provide an accurate percentage of the volume of the fat present but can also determine its spatial distribution

A New Example of Nanotechnology Applied to Minimally Processed Fruit:The Case of Fresh-Cut Melon

The effects of silver nanoparticles (Ag-MMT) incorporated into an alginate-based coating applied to fresh-cut melon (Cucumismelo L.) were assessed on the product shelf life. Different concentrations of Ag-MMT nanoparticles were tested in coated melon that was packaged in an oriented polypropylene-based bag and stored at 5°C. Results showed that the active coating was effective from the microbiological and the sensory point of view, if compared to the uncoated fruit that rapidly lost the characteristics responsible for fruit acceptance. A significant shelf life prolongation was recorded from less more than 3 days of the control samples to 11 days of coated fruit, thus promoting further investigation on Ag- MMT coating as valid preservation strategy

Effects of Cultivar and Process Variables on Dynamic-Mechanical and Sensorial Behavior of Value-Added Grape-Based Smoothies

The effects of either cooking temperature (45, 80, and 100 °C) or inclusion of seed particles on the dynamic-mechanical and sensorial properties of value-added Crimson seedless, Black Pearl, or Baresana grape-based smoothies were studied. The inclusion of seed particles resulted in significant increases of the phenolic content, both in Black Pearl and Baresana, but it did not affect in a negative way the sensorial characteristics of smoothies whereas it caused an increase of the viscoelastic behavior of Black Pearl and a slight decrease in Baresana grape-based smoothies. In particular, the investigated rheological parameters were the loss and storage modulus. Moreover, the loss tangent value (the ratio between loss and storage modulus) remained unchanged, indicating a pseudoplastic behavior of all samples, independent on the process conditions. The smoothies produced from Crimson grapes at the intermediate temperature (80 °C) showed sensorial and rheological characteristics similar to those manufactured at 45 °C and better than those manufactured at 100 °C

Processing and characterization of durum wheat bread enriched with antioxidant from yellow pepper flour

The effect of the addition of yellow pepper flour on bread physico-chemical and sensorial properties was addressed in this study. In particular, vegetable flour concentration was set at 25%; in order to optimize the bread sensorial properties, yellow pepper flour was separately hydrated at three different water content levels. Texture analysis were carried out on both dough and bread samples to evaluate their firmness. Furthermore, tomographic analysis was performed on the same samples in order to provide a more detailed view of their texture. Estimation of the glycemic response, determination of the carotenoids content and sensory analysis of the fortified bread were also determined. Results highlighted that the highest glycemic index was achieved in bread sample having the highest water content and that showed the worst results in terms of texture. Among the studied samples, bread with medium hydration level showed good structural characteristic, double anti-oxidant content compared to the control bread (CTRL S) and the highest sensorial quality

Influence of Heat Treatment on the Quality of Functional Gluten-Free Spaghetti

ABSTRACT In this study the influence of initial water content and the extent of flour thermal pre-treatment on both the dough rheological properties and the sensorial attributes of maize and chickpeas based gluten-free spaghetti were assessed. Results showed that samples with the highest initial water content had the highest values of elongation and shear viscosity, therefore dough with greater extensibility was obtained. Regarding the sensorial properties of non-cooked spaghetti, the overall quality of all samples had a very positive score with the exception of the samples with the highest initial water content and the lowest steam injection time that were scored just above the acceptability threshold because of their low resistance to break. The overall quality values of the cooked dry spaghetti were found to be around the acceptability threshold with the exception of the sample with the highest initial water content that showed a value higher than the threshold due to the highest values of bulkiness and adhesiveness