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Thermal characteristics of dried sugar beet pulp, leaves and leaf fractions obtained after extraction: fibrous leaf pulp and fibre rich leaf fraction, were investigated by differential scanning calorimetry and thermogravimetry. The sugar beet samples showed a similar thermal behaviour associated with a similar composition. Two endotherms are found on the differential scanning calorimetry curves. First one in the temperature range 31–153 °C and the second from 150–160 °C. Thermal degradation kinetics was studied by thermogravimetric analysis. Four degradation stages were observed within the temperature range 25–700 °C. The kinetic parameters of the degradation, obtained by Ortega and Friedman non-isothermal isoconversional methods did not significantly differ between models: Ea-activation energy at a conversion degree 0.1–0.9 ranged 50–200 kJ/mol; lnA- the natural logarithm of the pre-exponential factor 8–48; kp1-thermal degradation rate constant at a conversion extent of 0.5 ranged of 0.19–2.55 min−1. Constant rate of degradation is highest for the sugar beet leaves kp1 (2.58–2.55 min−1), and kp2 (70.1–70.4 min−1). The results obtained are valuable for sugar beet leaf industrial processing. A positive environmental impact is achieved by transforming the waste into high-value food additives. [ABSTRACT FROM AUTHOR]

The increasing demand for natural compounds as an alternative to synthetic antioxidants and conservans has led to the utilization of secondary plant metabolites in the food industry, as these bioactive compounds possess great antioxidative and antimicrobial properties without side effects on human health. Despite this, the sensitivity of plant-derived compounds is a restrictive factor in terms of their full potential. The current research aimed to characterize rosehip-fruit-extract-loaded liposomes (non-treated and UV-irradiated) in terms of their density, surface tension, viscosity, chemical composition (FTIR and HPLC analyses), and thermal behavior. In the storage stability study, the vesicle size, polydispersity index (PDI), zeta potential, conductivity, and mobility of the liposomes were monitored. FTIR analysis confirmed that the plant compounds were successfully loaded within the carrier, while no chemical reaction between the rosehip fruit extract and phospholipids was detected. The results of the HPLC analysis evidence the high potential for liposomal encapsulation to protect sensitive bioactives in the rosehip fruit extract from the degrading effect of UV irradiation. The size of the rosehip-fruit-extract-encapsulated liposomes increased on the seventh day of storage from 250 nm to 300 nm, while the zeta potential values were between −21 mV and −30 mV in the same period and further stabilized over 60 days of monitoring. In Vitro release studies in water and simulated gastrointestinal fluids showed that the presence of enzymes and bile salts (in intestinal fluid) enhanced the rosehip–polyphenol permeability from liposomes (70.3% after 6 h) compared with their release in water after 24 h and in gastric fluid after 4 h (38.9% and 41.4%, respectively). The obtained results indicate that the proliposome method was an effective method for rosehip fruit extract liposomal encapsulation and for the delivery of these plant-derived bioactives in foods. [ABSTRACT FROM AUTHOR]

Thermal characteristics of traditional dry fermented sausage from Srem County was studied by Differential Scanning Calorimetry (DSC). The aim of the study was to obtain the thermal characteristics and lipid oxidative stability of Serbian traditional dry fermented sausage from Srem County and considering results obtained could gave information about the quality and durability of sausage. The DSC thermogram of the sausage's meat assayed in this work, showed the characteristic endothermal transition in the low temperature range from -35°C to -10°C correspondning to water melting and in the temperature range from 90°C to 120°C correspondning to water evaporation. The DSC thermogram of the fat from sausage has three endothermal transitions, specific for pork lard. Oxidation stability of fat from the sausage was checked by DSC-OOT method and the kinetic parameters of the lipid oxidation (Ea energy of activation, Z preexponential factor and k oxidation rate constant) were obtained by the Kissinger-Akahira-Sunose (KAS) method. From DSC results obtained the free and bound water were determined, and information about lipid oxidation of sausage's fat suggested good overall stability and quality of meat product.

Studies were conducted to evaluate and compare the kinetic parameters related to the oxidation process of blackberry and raspberry seed oils in non-isothermal conditions by DSC. For that purpose, the oil samples were heated at six different heating rates, β (2, 5, 7.5, 10, 15, 20°C/min), starting from 40°C to the beginning of the oxidation process, under an oxygen flow of 50 ml/min. Experiments were performed using TA Instruments DSC Q1000, Differential Scanning Calorimeter (Delaware, USA). Kinetic parameters (activation energy, Ea (J/mol) andpre-exponential factor, A (min-1)) were calculated using isoconversional Ozawa-Flynn- Wall (OFW) method. Using the values of Ea and A the oxidation rate constant was calculated at 25°C and 120°C by Arrhenius equation. The oxidation rate constants of raspberry seed oil was about 2 times higher than that of blackberry seed oil, which indicates that blackberry seed oil is more stable in terms of oxidation.

Thermal analysis of osmotically treated fish (Carassius gibelio) meat was performed by three thermal techniques: Differential Scanning Calorimetry (DSC) Modulated Differential Scanning Calorimetry (MDSC) and Thermogravimetry (TGA). The objective of the study was to investigate the effects of osmotic solutions (sugar beet molasses and aqueous ternary solutions) on the thermal characteristics of osmotically dehydrated fish meat (Carassius gibelio). The DSC thermograms of all samples assayed in this work, showed the characteristic glass transition, the protein denaturation endotherm in the range of 40 °C-90 °C and no water melting peak, as a consequence of characteristic behavior of samples with high non freezable water content. The results obtained suggest the existence of different thermal characteristics depending on osmotic solutions used in process of osmotic dehydration. Those changes of thermal characteristics involve differences in overall thermal stability, protein stability, and differences in glass transition temperature (Tg).

Physicochemical properties of the sugar beet molasses (SBM), used as the medium for osmotic dehydration (OD) of pork meat, were determined to improve OD process performances. Macroelements content (Na, K, Ca and Mg) decreased in molasses after OD meat treatment, although rather slightly. Differential scanning calorimetry and modulated differential scanning calorimetry revealed that there was a strict dependence between water content and temperature of molasses glass transition, and suggested the character of the thermal process. Influence of the high organic content of molasses on the secondary lipid oxidation products of OD meat were determined using thiobarbituric acid method.

Nanostructured materials including three different carbonized polyanilines and manganese oxyhydroxide were prepared and evaluated as electrode materials for sensing of lead and cadmium ions in aqueous media. Anodic stripping voltammetry results indicated that all prepared materials could be successfully used for determination of these two heavy metal ions. Carbonized polyaniline-based electrodes have higher signal and lower limits of detection (10-7 М) compared to manganese oxyhydroxide-based electrode. Among the three studied carbonized polyanilines, the one that was derived from polyaniline precursor produced in the presence of 3,5-dinitrosalicyclic acid showed the highest electrocatalytic activity towards the lead and cadmium oxidation. [Projekat Ministarstva nauke Republike Srbije, br. OI172043 i br. III45014]

Studies were conducted on thermal properties of oils extracted from raspberry and blackberry seed as well as flours obtained by grinding of seed. Crystallization and melting points of oils were measured with a Differential Scanning Calorimetry (DSC), using TA Instruments DSC Q1000, under N2 purge flow of 50 ml/min. DSC scans were conducted in temperature range of 40 °C to -90 °C. A programmed cycle was followed in which the sample was cooled from 40 °C to -90 °C and heated back to 40 °C with rate of 2 °C/min. The raspberry and blackberry seeds oils presented a crystallization peak at -66 °C and -61 °C with enthalpy of 25.10 J/g and 29.04 J/g, respectively. Polymorphism was detected in both oils during heating.

Thermal behavior of and fresh and osmotically dehydrated pork meat in sugar beat molasses pork meat was studied by Differential scanning calorimetry (DSC). Samples of 7-11 mg (moisture content 5-20%) of osmotically dehydrated pork meat in aluminum pans were cooled from 20°C to -90 °C, equilibrated for 5 min and scanned initially from -90 °C to 150 °C at a rate of 5°C/min. The glass transition temperature (Tg) was determined from the DSC heat flow curves with TA Advantage software. Since much of the water was bound to the solid matrix, samples with low moisture content only showed up the glass transition. Tg decrease with increasing moisture content. Tg decreased from -6.0 °C to -10.1 °C when the moisture content increased from 5% to 20%. DSC curves of fresh pork meat did not showed the glass transition.