Whey Protein Concentrate Treated with Heat or High Hydrostatic Pressure in Wheat-Based Products

Commercial whey protein concentrate (CWPC) treated with heat or with high hydrostatic pressure (HHP) was incorporated by replacement into wheat flour, and its effects on dough rheology and the quality of cookies, noodles, and bread were evaluated. Wheat flour fortified with heat- or HHP-treated CWPC produced smaller cookies than those fortified with untreated CWPC. Increasing the fortification level of heat- or HHP-treated CWPC from 5 to 10% further decreased cookie diameter. The water absorption for noodle dough decreased by 5% with 10% fortification of untreated CWPC. Both heat- and HHP-treated CWPC increased water absorption from 33% in the control to 35.8%. Incorporation of untreated CWPC decreased the lightness (L*) value of Cantonese noodle dough, while dough fortified with heat- or HHP-treated CWPC had higher L* values compared to those of the control. Yellowness (b*) was improved with incorporation of both untreated and treated CWPC. Cooking loss of Cantonese noodles fortified with untreated or heat- or HHP-treated CWPC was comparable to or lower than that of the control. Incorporation of untreated CWPC increased hardness and cohesiveness of Cantonese noodles. Noodles fortified with heat- or HHP-treated CWPC had similar hardness and were softer than the control and the noodles fortified with untreated CWPC. Wheat flour fortified with 10% untreated CWPC produced wet and sticky bread dough and a small loaf (730 mL). Handling properties of dough were improved and bread volume was increased by 50 mL when heat- or HHP-treated CWPC was incorporated. Incorporation of 10% CWPC increased protein content of bread up to 20.2% and also increased the proportion of essential amino acids.     

Storage Conditions Affecting Increase in Falling Number of Soft Red Winter Wheat Grain

Falling number (FN) of wheat grain, a measure of preharvest sprouting, tends to increase during storage; however, grain and storage conditions that impact FN changes are poorly understood. Wheat grain samples of varying FN from several cultivars were obtained by artificial sprouting, by incubating wheat stalks, or directly from the field and were used to determine the effects of cultivar, storage temperature, grain moisture content, and initial FN on changes in FN and α‐amylase activity. Increases in FN of artificially sprouted grain during storage were affected by temperature but not evidently by grain moisture in the range of 10.0–13.0%. The FN of artificially sprouted grain increased when stored at 5, 23, and 35°C for 20 weeks by averages of 9.4, 24.1, and 34.4, respectively. The influences of storage temperature and initial FN of grain obtained from incubated stalks were different between cultivars when stored for 8 weeks. Wheat grain obtained directly from the field also exhibited significant increases in FN during 8 weeks of storage at 5, 23, and 35°C with average increases of 10.0, 27.1, and 38.5, respectively. The impact of α‐amylase activity on the increase in FN during storage was evident only for field‐harvested grain of varying FN. α‐Amylase activity exhibited a negative logarithmic relationship (R² = 0.87) with FN in field‐harvested grain. The magnitude of the changes in α‐amylase activity varied by cultivar.     

Seasonal Changes in Cystoseira Myrica and Phosphorus Input at Two Sites of the Red Sea Egyptian Coast

Elevated phosphate concentrations at Safaga and Quseir, Red Sea, Egyptian coast, wererelated to some ecological and nutritional aspects of the macro-alga Cystoseira myrica during1985. The results obtained were compared with those recorded for a non-polluted control site atGhardaqa. Chemical analysis of surface seawater samples revealed that the concentrations of dissolvedphosphate at Safaga and Quseir were 3 and 20 times as much as that at Ghardaqa, respectively.The standing crop of C. myrica showed two peaks in spring and autumn. Maximum biomass yield(491 g m-2) and number of individuals (127 m-2) of C. myrica were recorded in the spring at theGhardaqa site. Quseir C. myrica samples contained significantly higher protein-N, total-N andtotal-P values but lower carbohydrate values than the Safaga and Ghardaqa samples (LSD at 1%level). Tissue N:P molar ratios for C. myrica, Laurencia papillosa and Ulva lactuca collected fromGhardaqa ranged from 68-98, compared to 30-59 for the same species collected at thephosphorus polluted sites at Safaga and Quseir. The carbon levels and the C:N ratios of C. myricaexhibited no significant variations in the three studied sites. However, the C:P ratios of Ghardaqaplants were significantly higher than those of Safaga and Quseir.     

Effects of roasting on pyrazine contents and oxidative stability of red pepper seed oil prior to its extraction

Red pepper seeds were roasted with constant stirring for 6, 9, 10, and 12 min at 210 degrees C, and oils were extracted from the roasted red pepper seeds using an expeller. The iodine values and fatty acid compositions of red pepper seed oils did not change with roasting time. The fatty acid composition of the oil obtained from the red pepper seeds roasted for 6 min was 0.24% myristic acid, 13. 42% palmitic acid, 0.33% palmitoleic acid, 2.07% stearic acid, 10. 18% oleic acid, 73.89% linoleic acid, and 0.37% linolenic acid, showing a fatty acid composition similar to that of high-linoleate safflower oil. Thirteen alkylpyrazines were identified in the roasted red pepper seed oils: 2-methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, 2-ethylpyrazine, 2-ethyl-6-methylpyrazine, 2-ethyl-5-methylpyrazine, trimethylpyrazine, 2,6-diethylpyrazine, 2-ethyl-3,5-dimethylpyrazine, tetramethylpyrazine, 2, 3-diethyl-5-methylpyrazine, 2-isobutyl-3-methylpyrazine, and 3, 5-diethyl 2-methylpyrazine. The pyrazine content increased markedly as the roasting time increased, showing 2.63, 5.01, 8.48, and 13.10 mg of total pyrazine/100 g of oils from the red pepper seeds roasted for 6, 8, 10, and 12 min, respectively, at 210 degrees C. 2, 5-Dimethylpyrazine in the roasted red pepper seed oil seemed to be the component most responsible for the pleasant nutty aroma of the oils. The oxidative stabilities of oils increased greatly as the roasting time increased.     

Significance of Starch Properties and Quantity on Sponge Cake Volume

We evaluated the qualitative and quantitative effects of wheat starch on sponge cake (SC) baking quality. Twenty wheat flours, including soft white and club wheat of normal, partial waxy, and waxy endosperm, as well as hard wheat, were tested for amylose content, pasting properties, and SC baking quality. Starches isolated from wheat flours of normal, single‐null partial waxy, double‐null partial waxy, and waxy endosperm were also tested for pasting properties and baked into SC. Double‐null partial waxy and waxy wheat flours produced SC with volume of 828–895 mL, whereas volume of SC baked from normal and single‐null partial waxy wheat flours ranged from 1,093 to 1,335 mL. The amylose content of soft white and club wheat flour was positively related to the volume of SC (r = 0.790, P < 0.001). Pasting temperature, peak viscosity, final viscosity, breakdown, and setback also showed significant relationships with SC volume. Normal and waxy starch blends having amylose contents of 25, 20, 15, and 10% produced SCs with volume of 1,570, 1,435, 1,385, and 1,185 mL, respectively. At least 70 g of starch or at least 75% starch in 100 g of starch–gluten blend in replacement of 100 g of wheat flour in the SC baking formula was needed to produce SC having the maximum volume potential. Starch properties including amylose content and pasting properties as well as proportion of starch evidently play significant roles in SC baking quality of wheat flour.     

Synthesis and thermal properties of polyhydroxyamide copolymer and its derivatives

We synthesized a polyhydroxyamide (PHA) copolymer via low-temperature solution polymerization of 3,3'-dihydroxybenzidine with terephthaloyl chloride (80.0 mol%) and isophthaloyl chloride (20.0 mol%) in N,Ndimethylacetamide with the aid of LiCl. We prepared the PHA copolymer derivatives containing the fluorine-based substituents and investigated their solubility, cyclization behavior, and thermal properties using a differential scanning calorimeter (DSC), a thermogravimetric analyzer (TGA), and the simultaneous thermogravimetric analyzer coupled with a mass spectrometer (STA-MS). The chemical structures of the PHA copolymer and its derivatives, as well as the polybenzoxazoles (PBOs) obtained through thermal cyclization of the copolymer and derivatives, were determined by a fourier transform infrared (FT-IR) spectroscopic analysis. The PHA copolymer could be dissolved in organic solvents only with the aid of LiCl, while its derivatives were readily soluble in DMA_c and NMP without LiCl at room temperature. The DSC and TGA results demonstrated that the PHA copolymer derivatives could be converted to PBOs at a lower temperature than the PHA copolymer.     

Thermal properties of copolyetherester/silica nanocomposites

Thermal properties of copolyetherester/silica nanocomposites were examined by using DSC and TGA. The segmented block copolyetheresters with various hard segment structures and hard segment contents (HSC) were synthesized and their silica nanocomposite films were prepared by solution casting method. The nano-sized fumed silica particles were found to act as a nucleating agent of the copolyetheresters. The nanocomposites always showed reduced degree of supercooling or faster crystallization than the corresponding copolyetheresters. The nanocomposites also showed increased hard segment crystallinity except HSC 35 sample which had short hard segment length. In case of 2GT [poly(ethylene terephthalate)] copolyetheresters, which were not developed commercially because of their low crystallization rate, the hard segment crystallinity increased considerably. The copolyetherester/silica nanocomposites showed better thermal stability than copolyetheresters.     

Effects of Added Minerals on Pasting of Partial Waxy Wheat Flour and Starch and on Noodle Making Properties

Mineral content, as determined and expressed by ash content, serves as an index of wheat flour quality for flour millers and food manufacturers who prefer flour of low mineral content, even though the significance of mineral content on the functional properties of wheat flour is not well understood. We explored whether minerals have any influence on the functional properties of wheat flour and product quality of white salted noodles. Ash, obtained by incinerating wheat bran, was incorporated into two hard white spring wheat flours and their starches to raise the total ash content to 1, 1.5, or 2%. Pasting properties were determined using a rapid visco analyzer (RVA). Addition of ash increased the peak viscosity of the flours in both water and buffer solution but did not affect the peak viscosity of starch. Wheat flours with added ash showed lower pasting temperature by approximately 10°C in buffer solution. Mineral extracts (15.3% ash) isolated from wheat bran, when added to increase the ash content of wheat flour and starch to 2%, increased the peak viscosity and lowered the pasting temperature of flour by 13.2–16.3% but did not affect the pasting properties of the isolated starch. The mineral premix also increased peak viscosity of wheat flour but not in starch. Added ash increased noodle thickness and lowered water retention of cooked noodles while it exhibited no significant effect on cooked noodle texture as determined using a texture analyzer.     

Barley for food: Characteristics,improvement, and renewed interest

Barley (Hordeum vulgare vulgare L.) is an ancient cereal grain, which upon domestication has evolved from largely a food grain to a feed and malting grain. However, barley food use today remains important in some cultures around the world, particularly in Asia and northern Africa, and there is renewed interest throughout the world in barley food because of its nutritional value. This review covers basic and general information on barley food use and barley grain processing for food use, as well as an in-depth look at several major aspects/traits of interest for barley food use including kernel hardness and colour, grain starch, and β-glucan contents. These traits are described in terms of their effects on processing and nutrition, as well as their inheritance and the prospects for barley improvement through breeding. Whereas, the aspects listed above have been studied relatively extensively in barley in terms of content, form, genetics, physiology, and in some cases nutritional quality, little is know about functional properties for processing and food product development. Renewed interest in barley for food uses largely centres around the effects of β-glucans on lowering blood cholesterol levels and glycemic index. Wholegrain barley foods also appear to be associated with increased satiety and weight loss. There is great potential to utilise barley in a large number of cereal-based food products as a substitute partially or wholly for currently used cereal grains such as wheat (Triticum aestivum), oat (Avena sativa), rice (Oryza sativa), and maize (Zea mays).