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BACKGROUND The effect of high-pressure homogenization (HPH) on the rheological and thermal properties, water retention capacity (WRC), morphology and in vitro digestion of wheat starch was evaluated. Starch suspensions (50 g kg-1 , w/w) were treated at increasing pressures (up to 100 MPa) and numbers of cycles (up to 5) to generate a wide range of energy densities (70-500 MJ m-3 ) delivered to the sample during processing. RESULTS High-pressure homogenization induced a partial starch gelatinization confirmed by higher digestibility. Gelatinization degree (GD) was between 13% and 83%, causing a wide range of functional properties. High-pressure homogenization-treated starch samples showed WRC values of 810-1910 g kg-1 . Storage modulus (G') and complex viscosity (η* ) of starch dispersions were almost two and three times higher than the control at 13% and 83% GD, respectively. Positive linear relationships between GD (R = 0.98, P

Polypropylene (PP) based active composite films were prepared by adding butylated hydroxy anisole (BHA), butylated hydroxytoluene (BHT), and tertiary butylated hydroquinone (TBHQ) antioxidants using the extrusion molding process. All concentrations of BHT, 2% to 3% BHA, and 3% TBHQ significantly increased the tensile strength (TS) of the composite films compared with control films. Increasing antioxidant concentration decreased TS values for BHT films, whereas an opposite trend was observed for BHA and TBHQ films. BHA at 2%, and TBHQ at all added concentrations significantly reduced elongation at break (Eb ) of the composite films compared to control films. Water vapor permeability (WVP) of 1% BHT film was not significantly different from control. However, other antioxidants especially at increased concentrations significantly increased WVP values. TBHQ films with 300% to 662% increase had the highest WVP and BHT films with 5% to 81% increase had the lowest WVP among composite films. All three antioxidants had a negative effect on the transparency of the films; however the effect of BHA at higher concentrations was greater. The antioxidants did not change the color attributes of the films. Films containing all antioxidants showed 2,2-diphenyl-1-picrylhydrazyl radical-scavenging activity, which increased with increase in their concentration, especially for those containing 3 wt.% BHT and TBHQ. Overall, incorporating BHA and BHT into a PP matrix improved mechanical, barrier, antioxidant properties, and film appearance and consequently were proposed for the development of antioxidant active PP films. TBHQ film is not recommended for food packaging because of its weak mechanical properties (lower Eb and TS values, higher WVP, and greater migration).

In this study, starch-based films incorporating metal oxide (MO2 ) nanoparticles (NPs) of TiO2 and SiO2 (at a concentration of 1 to 4 wt. %) were produced by solution casting method. In order to exhibit antimicrobial properties, MO2 NPs were modified by synthesizing silver (Ag) ions over the NPs using cationic adsorption method. Ag ions were then reduced to metallic Ag by sodium borohydride solution. Scanning electron microscopy showed a smooth surface for the pure starch film. Incorporating MO2 @Ag NPs in the films increased surface roughness with agglomerated NPs within starch matrix. Energy dispersive X-ray analysis exhibited a uniform dispersion of Ag-loaded MO2 NPs, which increases surface contact between these NPs and the biopolymer matrix leading to improved physical and mechanical properties of the resulting films. With increasing in the NPs concentrations, the tensile strength and elongation at break % of the films increased and decreased, respectively. Incorporating MO2 @Ag NPs into starch matrix decreased solubility in water and water vapor permeability of the obtained films, and significantly inhibited the growth of Escherichia coli and Staphylococcus aureus. The most antibacterial effect was obtained for the films containing higher weight concentrations of Ag-loaded SiO2 -NPs.

Professional pasta cookers are filled with fresh water. The solids leached from the cooked pasta make pasta less firm and stickier while leading to changes in water properties and overflow. Added fresh water then has to be reheated. The effect of continuous cooking on cooked pasta quality and water properties was investigated for the first time by simulating professional pasta cooking on a laboratory scale. RESULTS Continuous cooking procedure of 12 batches led to a solid content of cooking water of 37?g?kg?1, resulting in an increase in shear-thinning behaviour and consistency index. Pasta cooking loss decreased from 52.7 to 35.7?g?kg?1 due to the lower water concentration gradient through the pasta. This was confirmed by a decrease in swelling index from 2.0 ? 10?3 to 1.6 ? 10?3?g?kg?1 during the optimal cooking time (13?min 45?s). Surprisingly, continuous cooking made the pasta firmer while stickiness did not differ significantly (P > 0.05). CONCLUSION Taking batch number 7 as the acceptability threshold, further studies are required to find an optimal solution for retaining cooking water properties highly affecting daily cooking procedures in food service kitchens. ? 2018 Society of Chemical Industry

The objective was to evaluate whether an ultrasonic reflectance technique has predictive capacity for breadmaking performance of doughs made under a wide range of formulation conditions. Two flours of contrasting dough strength augmented with different levels of ingredients (inulin, oil, emulsifier or salt) were used to produce different bread doughs with a wide range of properties. Breadmaking performance was evaluated by conventional large-strain rheological tests on the dough and by assessment of loaf quality. The ultrasound tests were performed with a broadband reflectance technique in the frequency range of 0.3-6 MHz.; Results: Principal component analysis showed that ultrasonic attenuation and phase velocity at frequencies between 0.3 and 3 MHz are good predictors for rheological and bread scoring characteristics.; Conclusions: Ultrasonic parameters had predictive capacity for breadmaking performance for a wide range of dough formulations. Lower frequency attenuation coefficients correlated well with conventional quality indices of both the dough and the bread. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

The objective was to examine the potential use of resistant starch (RS) as a fibre-enriching ingredient in gluten-free pasta. Pasta was enriched with commercial RS type II (Hi-Maize™ 260) at 100-200 g kg-1 substitution of rice flour. The effects on the rheological properties of dough and pasta quality as a result of RS addition and the loss in RS due to the process were evaluated.; Results: Dough water absorption was not influenced by the addition of RS. The cooking loss (CL) of RS-enriched samples was 30% lower than reference without fibre. The addition of RS significantly increased firmness of cooked pasta, and above 100 g kg-1 RS level of substitution samples showed a lower stickiness value. Dynamic rheological tests on pasta dough showed a higher storage modulus for fibre samples, indicating a higher number of elastically physical interactions. Loss in RS in uncooked pasta was about 31% compared with the initial amount added to the product.; Conclusions: The addition of RS improved the quality of gluten-free pasta owing to its ability to increase the firmness and decrease the CL and stickiness of cooked pasta. The product enriched with 200 g kg-1 RS can be considered a source of DF. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.

Summary. Background. Epidemiological studies of Aboriginal communities in Canada and Native American populations in the United States have reported that early childhood caries (ECC) is highly prevalent. The purpose of this study was to determine the prevalence of ECC and dental caries in the First Nations population of 3- and 5-year-old children in the District of Manitoulin, Ontario to assist in developing effective dental health promotion strategies. Methods. All 3- and 5-year-old children in elementary schools and day-care centres in seven First Nation communities were eligible for the survey examination. Three-year-old children at home and 5-year-old children attending school off-reserve in six of the communities were also eligible for epidemiological survey examination of oral health status including caries, gingival and soft tissue conditions. Cases of ECC were defined as children with caries or restorations on two or more primary maxillary incisors or canines or those having a total decayed, missing, filled primary teeth (dmft) score of 4 or greater. Results. A total of 87 children (59% 5 years old, 54% females) were examined. Seventy-four per cent of children had one or more carious lesions. Forty-five cases of ECC were found, a prevalence of 52%. The mean dmft score for cases was 7·5 (95% CI 6·5–8·4) and 0·8 (95% CI 0·5–1·1) for non-cases (P

Dynamic measurements were made with a controlled stress rheometer to study the viscoelastic properties (G', G', δ) of wheat doughs (45% wb water content) for fresh pasta production prepared with different blends of durum wheat semolina and common wheat flour with different concentrations of sodium chloride. Increasing the semolina and sodium chloride content, increased the strength and the solid-like behaviour of semolina-flour blends. The physical properties of dough were strongly dependent on particle size distribution and salt addition. By manipulating semolina-flour ratio and ionic strength, it was possible to obtain semolina-flour doughs with a rheological behaviour close to that of pure semolina dough.

In transmissible spongiform encephalopathies (TSEs), an altered form of prion protein (PrP), PrPres, aggregates in amyloid fibrils and accumulates in the brain. Several point mutations of the PrP gene have been associated with the TSEs, so, to investigate how the mutations affect the biological activity of PrP, we analyzed the biological effects and chemicophysical characteristics of the peptide homologous to the wild-type and mutated sequence of PrP fragments. The mutation P102L altered the biological activity of PrP 89-106, which became neurotoxic without changing its fibrillogenic capacity. The mutation (D178N) in the PrP 169-185 strongly increased the neurotoxic activity of the native sequence. In this case, there was also a clear alteration of the structural conformation. None of the other mutations considered, including A117V, seemed to influence the biological activities of the respective peptides. These data identify new neurotoxic fragments of PrP in the mutated form and elucidate their genetic influence on the pathogenesis of TSEs.

Radioimmunoguided surgery (RIGS) with radiolabeled monoclonal antibodies (MoAbs) has been reported as useful in second-look colorectal cancer procedures to improve surgical decision-making by helping avoid needless extensive surgery and expanding curative resection to sites of recurrence that have been missed previously. Sixteen asymptomatic patients with an history of colorectal cancer surgery underwent second-look surgery using the RIGS system, solely on the basis of rising serum levels of carcinoembryonic antigen (CEA). All patients were injected preoperatively with the anti-tumor-associated glycoprotein (TAG) 125I-labeled MoAb B72.3. Both traditional and RIGS exploration were used to determine the extension of a possible recurrence and its resectability for cure. Recurrent disease was observed in 14 of the 16 patients as the result of this combined exploration. Exploration alone showed the presence of recurrent disease in 9 of 16 patients (56.2%). Thus, RIGS found overlooked tumor in five patients (31.2%). All the additional RIGS-detected tumor sites were locoregional recurrences resectable for cure; conversely, no diagnostic improvements were shown in patients with liver metastases. Resection for cure was obtained by this approach in 9 of 16 patients (56.2%). Two patients without disease at the exploratory laparotomy recurred within 2 months at sites away from the abdomen. RIGS improved the results of colorectal cancer CEA-guided second-look procedures in asymptomatic patients by recruiting one-third of patients to curative resections.

Esterase antibody 522c2, the first example of a catalytic antibody specifically programmed to control the reactivity of functional groups on the side chain of tyrosine, accelerates the hydrolysis of benzoate esters of L-tyrosine and tyrosine-containing dipeptides by a factor of 104 and is moderately active against other benzoate esters.

The role of elective lymph node dissection (ELND) for treatment of cutaneous melanoma is still debated. Initially, lymphatic mapping technique was performed by an intradermic injection of vital blue dye; subsequently, it was improved by the use of radioguided surgery (RGS). Preliminary experience with this technique proved effective for detection of clinical occult lymph node metastasis; it may also enable the surgeon to perform a selective lymph node dissection (SLND) to concentrate on pathologic node-positive patients for the same potential benefits that have been provided by ELND. We performed sentinel node biopsy on 48 patients with stage pT3N0M0 melanoma. Vital blue dye mapping only was carried out on 39 patients; the remaining nine patients had a combined lymphatic mapping with both blue dye and RGS. The sentinel lymph node (SLN) was identified in 46 of 48 patients (95.8%). Ten patients (20.8%) were found to have metastatic melanoma cells in their SLN(s); all these patients underwent SLND of the affected basin. Our findings confirm that the intraoperative lymphatic mapping of the SLN using both blue dye and radiodetection is an appropriate and simple technique for selecting patients who are more likely to benefit from lymph node dissection.

Summary With the present research we tried to evaluate the contribution by maize (corn) to the spread of aphid vectors and in the maintenance of barley yellow dwarf virus (BYDV) in Friuli - Venezia Giulia (North East Italy). We also wanted to examine differences between two corn genotypes in relation to aphid colonisation. Some aspects of plant colonisation and the frequency of BYDV infected colonies in the two cultivars are discussed.