Interlaboratory Assessment of Dried Blood Spot Fatty Acid Compositions

Dried blood spots for fatty acid profiling are increasing in popularity; however, variability in results between laboratories has not been characterized. Whole blood from two subjects (low and high n-3 polyunsaturated fatty acid [PUFA] status) was collected, 25 μL applied to butylated hydroxytoluene (BHT)-treated chromatography strips, dried in air, and shipped to five laboratories. Results were reported as “routine” (typical fatty acids for each laboratory) or “standardized” (a set of 19 fatty acids), and outliers and variability (%CV) were determined. Five and eight outliers of a possible 91 measures each were identified by routine and standardized reporting, respectively, including eicosapentaenoic acid (EPA, 20:5n-3) in the low n-3 PUFA sample and arachidonic acid in the high n-3 PUFA sample. By standardized reporting, no outliers were identified for EPA or docosahexaenoic acid (DHA, 22:6n-3), and %CV decreased from 8.6% to 6.0% and 9.1% to 6.6% for EPA and 10.5% to 7.2% and 10.5% to 6.6% for DHA in the low and high n-3 PUFA sample, respectively. In conclusion, fatty acid profiles yielded few outliers, and standardization of reporting reduced the variability between laboratories.     

Milling and Processing of Wheat and other Cereals Affect Their Capacity to Inhibit Pancreatic Lipase in Vitro

The inhibition of pancreatic lipase activity by extracts of raw, milled or processed cereals was measured in vitro. The inhibitory activity was high in durum wheat, soft wheat and millet, moderate in barley and white sorghum and very low in red sorghum. Milling whole-grain into flours markedly decreased the lipase inhibitory activity in all species. In durum wheat, the germ and the aleurone-layer fraction exhibited the highest inhibitory activity. Processing of soft wheat by bread making, popping, flaking, drum-drying and extrusion-cooking, or durum wheat by making pasta markedly decreased the lipase inhibitory capacity. Extractible proteins were implicated in the inhibition process. These effects also had some nutritional implications.     

Use of a toasted durum whole meal in the production of a traditional Italian pasta: chemical, mechanical, sensory and image analyses

The characterisation of traditional Italian pasta obtained by mixing amounts of toasted whole meal with re-milled semolina and other ingredients was obtained by means of physico-chemical, rheological, mechanical, sensory and image analyses. The toasted meal showed higher ash, fibre and protein contents than re-milled semolina. The replacement of percentages of re-milled semolina with the toasted meal and soft flour increased tenacity and decreased extensibility and strength, making the dough less suitable for pasta-making. The P / L values were indices of high starch damage. The replacement of part of re-milled semolina and water with toasted whole wheat meal, soft flour and eggs increased the optimal cooking time and the amount of water absorbed during cooking but made the other cooking parameters worse. The image analysis provided evidence of the changes induced by the use of toasted wholemeal, soft flour and eggs in the microscopic structure of pasta protein and starch.     

Pasta with Unripe Banana Flour: Physical, Texture, and Preference Study

ABSTRACT:  Banana is a starchy food that contains a high proportion of undigestible compounds such as resistant starch and nonstarch polysaccharides. Products with low glycemic response such as pasta are considered favorable to health. The objective of this study was to use unripe banana flour to make spaghetti with low-carbohydrates digestibility and evaluate its physical and texture characteristics, as well as consumer preference. Formulations with 100% durum wheat semolina (control) and formulations with 3 semolina: banana flour ratios (85: 15, 70: 30, and 55: 45) were prepared for spaghetti processing. The use of banana flour decreased the lightness and diameter of cooked spaghetti, and increased the water absorption of the product. Hardness and elasticity of spaghetti were not affected by banana flour, but adhesiveness and chewiness increased as the banana flour level in the blend rose. Spaghettis prepared in the laboratory (control and those with banana flour) did not show differences in preference by consumers. In general, the preference of spaghettis with different banana flour level was similar. The addition of a source of undigestible carbohydrates (banana flour) to spaghetti is possible without affecting the consumer preference.     

Evaluation of the technological and sensory properties of durum wheat spaghetti enriched with different dietary fibres

The incorporation of fibres, whether insoluble or soluble, in durum wheat pasta negatively impacts desirable end‐use properties, especially if incorporated in significant amounts. Fibres can disrupt the starch–protein matrix of the dough during pasta preparation and can also often swell more readily with water than starch, competing with the starch for water during dough development. Similar degrees of substitution with different fibres gave markedly different impacts on firmness, stickiness, cooking loss and sensory attributes, suggesting that results obtained for one fibre cannot readily be generalized to other fibres. The in vitro starch digestibility of the pastas was significantly reduced when resistant starch, β‐glucan‐enriched flour, carboxymethyl cellulose or guar gum was incorporated but increased when pollard or inulin was added. In many instances, different sources of the same fibre gave dramatically different impacts on the properties of cooked durum wheat pasta. © 2014 Society of Chemical Industry     

Drying kinetics of whole durum wheat pasta according to temperature and relative humidity

Drying kinetics of bran-free and bran-rich pasta (whole durum) was determined according to temperature (40, 60 or 80 °C) and relative humidity (65%, 75% or 85%). Compared to temperature, relative humidity in drying chamber had a greater effect on pasta effective moisture diffusivity (α<0.01), and both parameters responded to a modified Arrhenius-type equation. Activation energy of pasta (11.4 kJ mol⁻¹) was lower than reported in the literature. Bran changed the course of pasta drying, depending on temperature and relative humidity. When relative humidity was higher than 75%, effective moisture diffusivity of bran-rich pasta decreased but the reverse was observed below 75%. Above 76 °C, equilibrium moisture content of bran-rich pasta was higher than bran-free pasta. In conclusion, optimal drying conditions for bran-rich pasta were different than standard (bran-free) pasta. Close control of relative humidity in pasta drying unit would be critical, especially under high relative humidity and high temperature conditions.     

Reduction in nitrogen oxides emissions by MILD combustion of dried sludge

Demands for the thermal treatment of sewage sludge are increasing due to the regulation of its ocean disposal and the desire to recover its potential energy. Because of the high nitrogen content in sewage sludge, one of the concerns about its combustion is a potential increase in NO_x emissions. Although a number of studies have been conducted to reduce NO_x emissions by combustion modifications, very few studies have addressed the combustion of dried sludge. In this study, a combustion technique called moderate or intense low oxygen dilution (MILD) was applied to the combustion of dried sludge with the goal of reducing NO_x emissions. MILD combustion of dried sludge was tested using both our laboratory-scale vertical combustor with internal circulation and our horizontal cyclone combustor with external circulation. Tests were conducted to find suitable operating conditions and to demonstrate the stable MILD combustion of dried sludge. From these tests, fuel and air flow patterns were found to be an important factor in maintaining stable MILD combustion, and the horizontal cyclone combustor demonstrated excellent performance in the reduction of NO_x emissions by the MILD combustion of dried sludge.     

Role of pasteurisation heat treatments on rheological and protein structural characteristics of fresh egg pasta

The influence of egg pasteurisation and of thermal treatment(s) of fresh egg pasta on the protein network in the pasta were studied. Protein structural parameters were correlated with the physico-chemical and rheological characteristics of pasta. Twelve samples of fresh egg pasta were laboratory-produced, using raw or pasteurised whole egg, and either left untreated or submitted to one or two pasteurisation processes. Industrial pasteurisation of the eggs did not affect the protein network of pasta or its rheological and functional characteristics. Double thermal pasteurisation of egg pasta deeply influenced its structural characteristics, due to the formation of a tight protein network stabilised by disulfide bonds, in which ovalbumin plays an essential role. This tight protein network affected the cooking behaviour and the rheological properties of fresh egg pasta, decreasing weight increase upon cooking and break strain, while increasing break load and Young modulus. The indexes derived from these studies were applied to the characterisation of 24 commercial samples of fresh egg pasta. By using the Young modulus before and after cooking (rheological parameters) and protein solubility in buffer-saline (structural parameter), it was possible to discriminate three groups of samples as a function of the severity of their thermal treatment.     

A novel approach to authenticity control of whole grain durum wheat (Triticum durum Desf.) flour and pasta,based on analysis of alkylresorcinol composition

Since durum wheat is ∼20% more expensive than common wheat and considered of superior quality for the manufacture of pasta products, efficient methods for the detection of accidental or intentional admixtures of common wheat to durum wheat products are required. This paper describes a novel approach for the detection and quantification of whole grain common wheat adulteration in whole grain durum flour and dried pasta. We found that differences in the C17:0 to C21:0 alkylresorcinol homologue ratios between the two cereal species may serve as a suitable tool for whole grain durum product authentification. To detect and estimate adulteration, the C17:0/C21:0 ratios of flour and pasta admixtures with added whole grain flour of common wheat were analysed. A linear relationship between C17:0/C21:0 ratios and level of admixture in pasta samples showed that adulteration can be estimated within the range of 5–100% of admixture. Furthermore, di- and triunsaturated as well as oxygenated alk(en)ylresorcinols are reported to occur in Triticum durum Desf. for the first time.