The enrichment of bread with wheat bran as a source of dietary fibre seems to be necessary for human health, because bread is the most consumed commodity in many countries. However, wheat bran has some adverse effects on the bread quality during storage. The aim of this study was to produce barbari bread with increased nutritional value and improved texture by the addition of coated wheat bran (0.67 and 1.34% based on flour stearic acid or St1, 2 and beeswax or Bw1, 2). Bread made from uncoated wheat bran was used as control. The least crust to crumb ratio was seen for control and Bw1. Water activity and moisture content results showed that the crumb of Bw1 and control had the better moisture retention during storage. Textural properties of samples showed that there were no significant differences in the hardness of the samples (P>0.05). However, the least increase in hardness during storage was observed for stearic acid coated samples. Other texture profile analysis parameters, such as cohesiveness and springiness, showed that Bw1 and Bw2 samples had no significant changes during storage. Differential scanning calorimetry (DSC) showed the least enthalpy for Bw1 after baking (385.21 J g–1) and during storage (567.62 J g–1). Accordingly, results showed that beeswax, especially at 0.67% (based on flour), is the best shell material for bran coating in order to improve bread texture and shelf life.
The comparative efficacy of 0.4% carboxymethyl cellulose (CMC) and 0.3% sodium alginate (SA) was evaluated as fat replacer in low-fat (<0.5% milk fat) mozzarella pre-cheese on the basis of physico-chemical, processing, textural, and colour profile, nutritional and sensory attributes. High-fat mozzarella cheese (prepared from milk with 6.0% fat) was taken as control (FFMC), whereas low-fat mozzarella cheese (prepared from milk with <0.5% fat) without any fat replacer (LFMC) taken as negative control. The per cent yield was lower in low fat cheese with CMC (LFMC-CMC), whereas in low fat cheese with SA (LFMC-SA) it was comparable with FFMC. The moisture and protein contents were higher (P<0.05) in low-fat mozzarella cheese (LFMC-CMC, LFMC-SA) than in FFMC. The energy content in LFMC-CMC and LFMC-SA was 44 percent lower than in FFMC. The meltability decreased, whereas melt time increased in LFMC-CMC and LFMC-SA compared to FFMC. The processing and nutritional attributes were comparable in both treatments. Hardness increased, whereas chewiness decreased in low-fat cheese. However, type of fat replacer did not affect hardness of the product. Gumminess was higher (P<0.05) in LFMC-CMC than in LFMC-SA. The sensory panellists rated LFMC-SA better for flavour and overall acceptability than LFMC-CMC. The appearance, texture, and juiciness were comparable in low-fat and high-fat mozzarella cheese. Results indicated that 0.3 per cent SA can be successfully used for processing of low-fat cheese.
Authors:I. Rumora, I. Kobrehel Pintarić, J. Gajdoš Kljusurić, O. Marić, and D. Karlović
This study elucidates the key success of using statistical modelling in the design and development of a new product (milk toffee) as potential new functional food product. The standard milk toffee recipe was modified in order to produce new products with less sugar, more inulin, and decreased energy content. From the consumers point of view, a product has to be healthy (acceptable ingredients like low sugar content or inclusion of inulin) and tasty (good sensory properties). This is an opportunity to use chemometric strategies that can highlight information in relation to different ingredients and preferable taste attributes. Multivariate exploratory techniques were used in order to detect relationship between the milk toffee ingredients (sugar, water, condensed milk, glucose syrup, fat, salt, sorbitol, and emulsifier E 471) and sensory attributes of taste and texture (sweetness and hardness) chosen for this research.Results showed that the sweetness is a direct outcome of added sugar, glucose syrup, and condensed milk, and the hardness, as the next important sensory attribute of a milk toffee, is positively correlated with the content of fat, glucose syrup, water, salt, and E 471. Statistical modelling proved to be a useful tool for elucidating the relationship between ingredients and sensory properties of the milk toffee and can be a useful tool in the complex interpretations of changes in product design and development.
The influence of the structure of succinic or glutaric anhydride modified linear unsaturated (epoxy) polyesters on the course
of the cure reaction with styrene initiated by benzoyl peroxide (BPO) or the mixture of benzoyl peroxide/tetrahydrophthalic
anhydride (BPO/THPA) or benzoyl peroxide/maleic anhydride, as well as viscoelastic properties and thermal behavior of their
styrene copolymers have been studied by DSC, DMA, and TGA analyses. Additionally, mechanical properties: flexural properties
using three-point bending test and Brinell’s hardness for studied copolymers were evaluated. It was confirmed that the structure
of used polyesters had a considerable influence on the course of the cure reaction with styrene, viscoelastic, thermal, and
mechanical properties of prepared styrene copolymers. Generally, one or two asymmetrical peaks for the cure reaction of succinic
or glutaric anhydride modified linear unsaturated epoxy polyesters with styrene were observed. They were connected with various
cure reaction, e.g., copolymerization of carbon–carbon double bonds of polyester with styrene, thermal curing of epoxy groups,
polyaddition reaction of epoxy to anhydride groups in dependence of used curing system. In addition, only one asymmetrical,
exothermic peak attributed to the copolymerization process of succinic or glutaric anhydride modified linear unsaturated polyesters
with styrene was visible. Moreover, the obtained styrene copolymers based on succinic or glutaric anhydride modified linear
unsaturated epoxy polyesters were characterized by higher values of
, Tg, E″, νe, Emod, Fmax, hardness, IDT, FDT but lower ε − Fmax compared to those values observed for styrene copolymers prepared in the presence of succinic or glutaric anhydride modified
linear unsaturated polyesters. This supported to the production of stiffer and more thermally stable polymeric structure of
copolymers based on unsaturated epoxy polyesters. Moreover, the copolymers prepared in the use of glutaric anhydride modified
linear unsaturated (epoxy) polyesters were described by lower values of
, Tg, E″, νe, Emod, Fmax, hardness, IDT, FDT but higher ε − Fmax than those based on succinic anhydride modified linear unsaturated (epoxy) polyesters. The presence of longer aliphatic chain
length in polyester’s structure leads to produce more flexible network structure of styrene copolymers based on glutaric anhydride
modified linear unsaturated (epoxy) polyesters than those based on succinic anhydride modified linear unsaturated (epoxy)
Authors:J. Rincón, M. Romero, A. Hidalgo, and Ma. Liso
It has been determined the thermal behaviour at high temperatures of an iron aluminum arsenate mineral first described in
the location of La Serena Valley, Extremadura, Spain, which expands until 1173 K contracting later and softening at 1653 K
and full melting at 1773 K. The DTA/TG experiment only detects some rearrangement with an endothermic at 1173 K due to the
mica mixing. The mineral is a scorodite variety mixed with micaceous clay which has been found as aggregates of pyramidal
crystals associated with quartz, wolframite, molibdenite, cassiterite and other secondary minerals in the pegmatite of the
San Nicolas mine. The chemical composition, the physico- chemical characteristics such as density and hardness, as well as
the thermal behaviour has allowed to conclude that this mineral can be an Al-enriched scorodite (mansfieldite): (Fe, Al) AsO42H2O mixed with illite from the scorodite-mansfieldite series.
Authors:E. Elshereafy, Maysa Mohamed, M. EL-Zayat, and A. El Miligy
Nitrile butadiene rubber (NBR) was mixed with high density polyethylene (HDPE) thermoplastics with different ratio namely
(100/20), (100/40), (100/60) and (100/80). The obtained blends were subjected to gamma irradiation with varying dose from
50 to 250 kGy. The induced crosslinking and hence the improvement in the different properties were followed up as a function
of irradiation dose. Mechanical properties as tensile strength, tensile modulus at 50 % elongation, elongation at break percent,
permanent set and hardness were carried out as a function of irradiation dose and blend ratio. Moreover, physical properties
namely, gel fraction % and swelling number were found to improve with the increase of irradiation dose up to 250 kGy and with
the increase of the content of HDPE in blend. Moreover, presence of NBR enhances the shrinking properties of the obtained
blend which can be used as a good heat shrinkable material.
Authors:N. Eissa, N. Sheta, H. El Bahnasawy, T. Amer, and H. Sallam
Mössbauer measurements were performed at different temperatures in order to examine the dynamic behavior of iron in the glass system: 42.5% P2O5, 42.5% Na2O, 15% Fe2O3. Variation of the dynamic behavior was traced by substituting B2O3 for P2O5 [30 P2O5, 12.5 B2O3, 42.5 Na2O, 15 Fe2O3] and by increasing the amount of iron at the expense of Na2O [42.5 P2O3, 15 Na2O, 42.5 Fe2O3]. The Mössbauer measurements gave the values of Debye temperature (
D), mean square displacement <
2>, mean square velocity <v2 > of oscillation, the lattice time () and the strength parameter (B) for each glass. These values were discussed with the results of DTA, density, hardness and D. C. conductivity.
Authors:C. Dueñas, M. Fernandez, E. Liger, S. Cañete, A. Fernandez, and R. Perez
The measurements of radioactivity in drinking water enable us to determine the exposure of the population to radiation through
their usual consumption of water. An intensive study of the water supply in the city of Malaga has been carried out to determine
both the gross alpha-and gross beta-activity concentrations. Gamma spectrometry was used in order to detect certain types
of radionuclides. Results indicated that 95% of the water tested contained a gross alpha-radioactivity of less than 0.1 Bq/1,
and 100% gross beta-activity of less than 1 Bq/1 — the activity limit recommended by the Spanish Regulatory Organization.
Several factors were found to have an influence on radioactivity levels, such as total hardness, potassium and pH.
The precipitation of a supersaturated 6061 Al alloy reinforced with 10% SiCpwas monitored by using a DSC technique. DSC thermal curves were used to predict peak-aging temperatures and durations. The
activation energies for precipitation of the β″ phase were found to increase with elevation of the solution temperature from
510 to 600°C, and hence the peak-aging temperature and duration also increased. Microstructural examination revealed an increase
in grain size when a high solution temperature was applied. To compare predicted peak-aging temperatures and durations, hardness
measurements were carried out after artificial aging. The studies revealed that peak-aging hardening was obtained when the
aging temperatures and durations corresponded to about 95% to 97% precipitation of β″ phase from conversion plots.
Authors:V. Singh, N. Guizani, I. Al-Zakwani, Q. Al-Shamsi, A. Al-Alawi, and M.S. Rahman
Eight descriptive sensory textural attributes of whole date fruit were evaluated by twenty trained panel members and correlated with sixteen physicochemical properties. All sensory parameters, except gumminess, significantly correlated (Ps<0.05) with pectin, crude fibre, and moisture content. In addition, sensory hardness, cohesiveness, elasticity, and resilience correlated significantly with length of whole fruit (P<0.05), sensory adhesiveness with glucose content (P<0.05), sensory chewiness with mass of whole fruit (P<0.05), and sensory gumminess with fructose, glucose, and total sugar content (P<0.10). Sweetness, however, correlated only with moisture content (P<0.05). CA and the biplot (i.e. including all products, their sensory texture and physicochemical attributes) generated through PCA recognized three groups of dates as hard-chewy, soft-(medium-chewy), and soft-(non-adhesive).