Influence of Whey Protein Addition and Feed Moisture Content on Chosen Physicochemical Properties of Directly Expanded Corn Extrudates

Production of extrudates from cereals is an often-used technological process in today’s world food industry. Extrudates from corn flour produced using the twin-screw extrusion process and enriched with whey protein concentrate represent high-quality source of proteins and fats. Whey protein concentrate (WPC) as a valuable source of proteins and minerals is one of the highest-quality components for possible extrudate enrichment. In this paper, the influence of various WPC addition and some extrusion process parameters such as feed moisture content ( Q_{textHtext2 textO} Q_{{{text{H}}_{text{2}} {text{O}}}} ) on physicochemical properties of directly expanded corn flour extrudates manufactured in twin-screw co-rotating extruder was investigated. Whey protein concentrate was added in the following ratios 7.5%, 15% and 22.5% and water in 10.08, 12.18 and 14.28 L/h. Final composition of products is determined with measuring of protein, fat and water shares, water absorption index (WAI) and water solubility index (WSI). With added WPC and with increase of water volume flow, there was a significant rise in total protein, fat and water content in final products, as well as lowering of WSI and rising of WAI indexes. The statistical analysis of the obtained data shows that the lowest WSI and the highest WAI had samples with the largest share of WPC (22.5%) and water volume flow of 14.28 L/h. Colour is measured for each sample, and results were represented with hue angle (H), chroma (C) and lightness (L) values. Process parameters, WPC and Q_{textHtext2 textO} Q_{{{text{H}}_{text{2}} {text{O}}}} influence the increase of saturation of C and lightness of L colour value, while H value stays unchanged. Mean value of H was 90.14 ± 1.06, which corresponds to dominance of yellow colour of samples.     

The effects of wet sorghum distillers' grains inclusion on napiergrass silage quality

This paper studies different amounts of wet sorghum distillers' grain (WSDG) for inclusion in napiergrass silage for silage fermentation. Napiergrass was harvested, chopped and mixed in four different ratios with WSDG. The ratio of WSDG to napiergrass on a dry matter basis was 0, 20, 40 and 60% respectively in four different dietary treatments. These materials were ensiled in 60 laboratory mini‐silos, 45 cm in height and 21 cm in radius. The napiergrass was put into 56 containers, which included two replicates for each of the four treatments. Each treatment utilised seven silage containers for each sampling time. Every two replicate mini‐silos were opened and sampled for analysis at 0, 1, 2, 4, 8, 16 and 32 days after ensiling respectively. One silage container from each treatment was installed with a remote‐controlled electronic thermometer to record temperature changes. Sample analyses included determination of pH, titratable acidity, buffering capacity, neutral detergent fibre (NDF), acid detergent fibre (ADF), crude protein, ammonia nitrogen, lactic acid, volatile fatty acids (VFA), water‐soluble carbohydrates (WSC), dry matter (DM) and ash. The results of the silage characteristics at the end of the 32 day ensilage showed that the pH value of the 40% WSDG group was significantly lower (P < 0.05) than that of the other treatment groups. The titratable acidity, buffering capacity and water‐soluble carbohydrates of the control group were significantly lower (P < 0.05) than those of the other groups. Lactic acid production by the 20% WSDG group was significantly higher (P < 0.05) than that of the other treatment groups. Lactic acid production in the control was significantly lower (P < 0.05). The ammonia N concentration of the total N of the 60% WSDG group was significantly lower (P < 0.05) than that of the other groups. The Flieg score of the control was 85, the 20% group was 93, the 40% group was 95 and the 60% group was 91. © 2000 Society of Chemical Industry     

皮革废料中提取的胶原蛋白性能研究

研究了利用生物酶技术提取的制革废皮料中的胶原蛋白水溶液在不同p H值、胶原蛋白浓度、电解质浓度等条件下的溶解性能及乳化能力,获得了溶解度与乳化能力在上述条件下的变化趋势。     

The relationship of carcass measurements to carcass composition and intramuscular fat in Spanish beef

Forty beef carcasses were classified for conformation and fatness. Besides, carcass weight, fat thickness (FT), carcass dimension, marbling by computer image analysis and ultrasound readings was recorded to complement grading. For predicting intramuscular fat (IMF) content, FT, number of intramuscular flecks and conformation increased R²-value from 0.19 to 0.64 compared to conformation alone. For visual marbling, ultrasound readings and thoracic depth (TD) increased the R²-value from 0.24 to 0.57 compared to fatness score (FS). The best variables for predicting weight of fabricated subprimals were carcass weight or compactness which is a function of carcass weight (R² between 0.94 and 0.63). Fatness score was poorer than FT for predicting yield of subprimals cuts from round (R² = 0.16 vs. 0.50) and ultrasound readings for less valuable subprimals (R² = 0.31 vs. 0.39). These results showed that other variables could be used in combination with carcass fatness or conformation to achieve a more accurate estimation of fat and carcass yield.     

基于光纤微弯的缠绕式管道形变传感器

利用多模光纤的微弯特性 ,提出并实现了一种新颖的光纤缠绕式管道形变传感器 ;也给出了它的基本实验原理 .研究表明多模光纤的微弯损耗对导管的变形响应灵敏 ,其灵敏度可达 3.5 d B/ με.并且实验与理论符合的很好     

Assessment of antioxidant activity and phycocyanin release of Spirulina loaded poly(ε-caprolactone) electrospun nanofibers

PCL with biodegradable property and Spirulina with various biological activities offer good alternative ingredients for the fabrication of functional nanofibers in tissue engineering. The aim of the study is to obtain PCL/Spirulina nanofibers with low diameters and to determine their wettability, antioxidant activity, and phycocyanin release to evaluate their potential as bioactive scaffolds in different applications. PCL/acetic acid/pyridine solutions with three different Spirulina concentrations were electrospun and the obtained nanofibers were investigated. The thinnest PCL/Spirulina nanofibers (117.20 nm) were obtained at 1.5% Spirulina concentration. Although PCL nanofibers with 6% Spirulina concentration showed the highest antioxidant activity and amount of phycocyanin released, PCL nanofibers with 3% Spirulina concentration having similar in vitro results showed superiority when considering the diameter and uniformity of the nanofibers and the cost of the material. The PCL/Spirulina nanofibers with small diameters and antioxidant activity could be regarded as potential extracellular matrix material for tissue engineering.     

G-quadruplex formation of oligonucleotides containing ALS and FTD related GGGGCC repeat

A largely increased number of GGGGCC repeats located in the non-coding region of C9orf72 gene have been identified as the leading cause of two related neurological disorders, familial amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). We examined G-quadruplex forming ability of GGGGCCrepeat containing oligonucleotides with four guanine tracts chosen as the smallest possible model to form a unimolecular G-quadruplex. These oligonucleotides are readily to folded into G-quadruplexes in the presence of K⁺ ions. However, the formation of multiple structures makes structural analysis challenging and time consuming. We observed that flanking sequences on 5'- and 3'-ends as well as mutations of loop residues have a profound effect on folding. Sequence d[(G₄C₂)₃G₄] was chosen for further scrutiny and optimization of nuclear magnetic resonance (NMR) spectroscopic properties with dG to 8Br-dG substitutions at specific positions in the sequence under different folding conditions. Expectedly, folding into desired predominant topology is facilitated when substituted residue adopted a syn conformation in the naturally-occurring structure. Single dG to 8Br-dG substitution at position 21 and fine tuning of folding conditions facilitate folding of d[(G₄C₂)₃GG^BrGG] into (mostly) a single G-quadruplex, and thus enable determination of its high-resolution structure by high-field NMR.

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Ternary composites of polypropylene,elastomer, and filler: Analysis of phase structure formation

Investigation of the morphology and properties of ternary composites of polypropylene, ethylene-propylene-diene terpolymer, and filler has shown that in such systems two kinds of structures can be formed: separate dispersion of the components or encapsulation of the filler by the elastomer. A thermodynamic analysis of the two structures revealed that encapsulation is the thermodynamically favored process. The final structure is determined by the stability of the encapsulated units, which depends on the relative magnitude of adhesion and shear forces. The former depends on the reversible work of adhesion and on the particle size of the filler, while the latter depends on the viscosity and shear rate. Surface treatment of the filler decreases the work of adhesion, resulting in extensive de-encapsulation. The developed tentative explanation is in agreement with the observed phenomena and experimental results.     

新璎分体式斜顶在注射模具中的应用

斜顶事模具成型中的重要结构,斜顶的优劣直接影响着产品的质量,新型分体式斜顶是由传统整体式斜顶改进而来,具有强度高,使用寿命长,制造周期短,成本低到呢个优点,为注塑模具制造生产带来了更高的效益,运川越来越广泛