1,721,010 research outputs found
Evaluation of the Effects of Different Fermentation Methods on Dough Characteristics
No full textDough characteristics as affected by different preferment types and fermentation times were evaluated. A dough type was obtained with yeasted stiff preferment (60% water), fermented for a long period (biga-type dough - B) and another one made with a semiliquid preferment (100% water), obtained with sourdough and fermented for a short period (poolish-type dough - P). The doughs obtained were compared with a standard dough (direct dough - D). During the first 60min of fermentation, pH, titratable acidity, volume, empirical and fundamental rheological properties and gas cells number were evaluated. During fermentation time, all doughs underwent structural changes related mainly to an increase of resistance to the extension and a decrease of area and extensibility, with a noticeable change in volume and pH. Between all samples, B dough was the stiffest reaching the lowest volume (44.3mL), the highest storage modulus (G′=10,982Pa) and resistance to extension (31.78g)
Microstructural and rheological characteristics of dark, milk and white chocolate: A comparative study
Full text linkThree different chocolate types: dark, milk and white were characterized and compared for the microstructural and rheological (fundamental and empirical) characteristics. A light microscope coupled to an image analysis system was employed in order to evaluate the particle size, the network structure and the distance between particles of each matrix. Rheological parameters (yield stress, viscosity, thixotropy) were evaluated by using a stress-strain rheometer, while mechanical properties (consistency and cohesiveness) were analysed using a texture analyzer. The Power law, Casson and Windhab rheological models were used in order to better explain the rheological behaviour of chocolate samples. Results showed that white chocolate, with the highest amount of fat in formulation, had the smallest sized particles, the less aggregate structure and the lowest yield stress, viscosity and thixotropic values. Dark chocolate samples instead presented the highest aggregate structure, with less void spaces between particles that involved the highest rheological parameter values. Milk chocolate matrix exhibited intermediate microstructural and rheological characteristics compared to dark and white chocolate ones
Microstructural and Rheological Properties of White Chocolate During Processing
No full textThe relationship between the microstructural and rheological properties of white chocolate was studied during the main steps (mixing, pre-refining, refining, conching and tempering) of the manufacturing process. Laser light diffraction and light microscope techniques were used to study the particle size distribution (PSD) and the modifications of the network structure of the samples. Rheological parameters in terms of yield stress, apparent viscosity and thixotropy were evaluated by using a stress-strain controlled rheometer. The Casson and Windhab rheological models, which are widely used for dark and milk chocolate matrices, were used in order to explain better the rheological values obtained from the flow curves. Particle analysis revealed significant changes in the network structure during process. In particular, from the mixed sample to the refined one, a reduction in particle size was found; Sauter (D[3.2]) and Feret diameters decreased, the former from 18.6 to 6.67 μm and the latter from 320 to 33 μm. Consequently, an increase in the matrix aggregation was observed. The white chocolate samples obtained from the conching and tempering steps were characterized by the statistically lowest values of yield stress and apparent viscosity and by the weak structure. Moreover, the samples were well discriminated by both rheological models applied
Food Preparation with mushrooms and making process
Full text linkThe present invention relates to a food preparation according to the preceding claim, characterized in that it comprises, in weight percentage on the total weight, 20% to 60% dietary fats, 5% to 40% mushrooms calculated in dry residue condition, 20% to 60% water and at least one thickening ingredient. The percentage of mushrooms considered in the dry residue condition derives from the presence of a liquid extract of mushrooms, preferably concentrated, and/or mushroom powder and/or a dry residue resulting from a mushroom extract. The preparation has the appearance of a homogeneous mixture with a creamy or frosting texture. In the process, the ingredients are combined together by mixing fats and at least one thickening ingredient first, and then adding the remaining ingredients
Physico-chemical and metabolomic characterization of KAMUT® Khorasan and durum wheat fermented dough
No full textInvestigations were made in order to evaluate the influence of the flour type, chemical acidification and fermentation on characteristics of doughs obtained with durum wheat and KAMUT Khorasan flour. Doughs were observed immediately after mixing, 90 and 360 min of leavening at 30 C. Fundamental rheology, yeasts heat production by isothermal microcalorimetry and the interaction between water and biopolymers by means of time domain nuclear magnetic resonance were evaluated. In addition aromatic metabolite development was followed by means of the combined application of gas-chromatography and electronic nose. KAMUT Khorasan flour was found to be more suitable than durum wheat for the fermentation processes
tested, especially at acidic conditions, as shown by the increase of the volume and the metabolic heat production by yeast. In acidified dough the pattern of volatile metabolites allowed a clear distinction between the types of dough. Moreover the water/starch proton pool was characterized by higher T2 values in the KAMUT Khorasan samples
Evaluation of drying of edible coating on bread using NIR spectroscopy
No full textEdible coatings are recently gaining attention for potential applications in bakery products to extend the shelf-life and incorporate functional characteristics, like probiotics, antimicrobial or an antioxidant compound, for which drying of the coating is an essential step. The aim of this work was to utilize near infrared (NIR) spectroscopy as a tool to rapidly monitor and develop predictive model for the drying of edible coating on bread (mini-burger buns) surfaces. The buns coated with edible coating were dried at two different temperature regimes, at 25 °C and 60 °C for one layer of coating and one temperature regime at 60 °C for two layers of coating. NIR spectra were collected and moisture content was determined at different drying times. The spectral data were pre-treated and subjected to Principal component analysis (PCA) for discrimination of drying times and subsequently to Partial least squares (PLS) regression for moisture prediction for given temperature, time and surface. Results show that NIR spectroscopy was able to reflect the drying process and discriminate between the various surfaces of bread and times of drying, primarily by the differences in water and protein absorption bands (1940 nm, 1500 nm, 2050 nm). Also, the subsequent PLS regression of the spectral data was found to describe satisfactorily the drying behaviour and the optimal drying moment with RMSE values ≤ 3% for the calibration and cross validation data sets. The procedure proposed could be used for faster quantification of moisture during drying process
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Panificabilità di farine derivanti da varietà di grani antichi
No full textThe modern plant breeding of the “ancient” grains produced modern wheat varieties with high agronomic yield and technological quality. However, these hybrids have lost some of nutritional properties of the ancestral wheats (Arzani, 2011). Nowadays one of the most attractive aspect in the use of food product obtained from “ancient” wheats is the relatively hypoallergenicity in comparison to food products made from common wheats (Carnevali et al, 2014). Recently industry and researchers are involved in optimizing bread-making technology to improve quality, taste and availability of new and diversified products. To this end the realization of enriched new bread, obtained by using “ancient” wheat should be promising for industry and consumers requests.
This research will be focused on the selection of two under or not utilized “ancient” wheat varieties (Gentil Rosso and Rieti) and compared with a modern cultivar (MEC). The bread making process suitability of the selected ancient wheat varieties will be evaluated to establish the right formulations and process parameters. Moreover, the enriched bread physico-chemical, rheological sensorial and aromatic characteristics will be evaluated also during storage
- …
