Effect of Spray Nozzle Design on Fish Oil–Whey Protein Microcapsule Properties

Abstract: Microencapsulation improves oxidative stability and shelf life of fish oil. Spray and freeze drying are widely used to produce microcapsules. Newer spray-nozzles utilize multiple fluid channels allowing for mixing of wall and core materials at the point of atomization. Sonic energy has also been employed as a means of atomization. The objective of this study was to examine the effect of nozzle type and design on fish oil encapsulation efficiency and microcapsule properties. A total of 3 nozzle types, a pressure nozzle with 1 liquid channel, a pressure nozzle with 2 liquid channels, and a sonic atomizer with 2 liquid channels were examined for their suitability to encapsulate fish oil in whey protein isolate. Physical and chemical properties of freeze dried microcapsules were compared to those of microcapsules produced by spray drying. The 2-fluid pressure and ultrasonic nozzles had the highest (91.6%) and the lowest microencapsulation efficiencies (76%), respectively. There was no significant difference in bulk density of microcapsules produced by ultrasonic and 3-fluid pressure nozzles. The ultrasonic nozzle showed a significantly narrower particle size distribution than the other nozzles. This study demonstrated that new nozzle designs that eliminate emulsion preparation prior to spray drying can be beneficial for microencapsulation applications. However, there is still a need for research to improve microencapsulation efficiency of multiple channel spray nozzles. Practical Application: Since this research evaluates new spray nozzle designs for oil microencapsulation, the information presented in this article could be an interest to fish oil producers and food industry.     

Synthesis and Properties of Boron Doped NaxCo2O4 Nanocrystalline Ceramics

Sodium cobalt oxide (NaCo₂O₄) nanofibers with diameters ranging between 20 and 200?nm were prepared by electrospinning a precursor mixture of PVA/(Na–Co) acetate. This was the first time any such attempt was made. Afterwards, the electrospun nanofibers were subjected to calcination treatment. The characteristics of the fibers were investigated using a Fourier transform infrared spectroscopy, a X-ray diffractometer, and a scanning electron microscopy. The boron doped and undoped NaCo₂O₄ nanofibers calcined at 850?°C were polycrystalline of the γ Na_xCo₂O₄ phase having diameters ranging between 20 and 60?nm with grain sizes of 5–10?nm, and the nanofibers calcined at 800?°C were single crystals having linked particles or crystallites with particle sizes ranging between 60 and 200?nm. The results indicated a significant effect of calcination temperature on the crystalline phase and morphology of the nanofibers. It could be seen in the SEM micrograph of the fibers that when boron was added, this resulted in the formation of cross-linked bright-surfaced fibers. The average fiber diameter for boron doped and undoped fiber mats were 204 and 123?nm, respectively. The grain diameters of boron doped and undoped nanocrystalline sintered powders were measured as 140 and 118?nm, respectively.     

Policosanol contents of beeswax,sugar cane and wheat extracts

Policosanol (PC) is a mixture of high molecular weight aliphatic primary alcohols. Currently, a number of dietary supplements containing PC are commercially available in the US market. The majority of these products are prepared from beeswax or sugar cane extracts. The main objective of this study was to compare the PC contents and compositions of beeswax, sugar cane and wheat as PC sources. The PC contents and compositions of several commercial dietary supplements were also analyzed. The precipitate formed during the cold storage of commercially hexane-extracted wheat germ oil (WGO) contained the highest total PC (628 mg/kg) among the wheat extracts and milling products examined in this study. The total PC contents of wheat straw (164 mg/kg) and sugar cane peel (270 mg/kg) were of the same order of magnitude. The total PC contents of brown beeswax were about 20 and 45 times higher than those of the WGO-solids and sugar cane peel, respectively. Commercial dietary supplements contained less total PC than were claimed on the product labels. The PC compositions of the samples analyzed in this study varied significantly with the source. Wheat can be a viable PC source for further product development or health benefits.     

Application of enzymes and chitosan biopolymer to the antifelting finishing process

We surveyed environmentally friendly chemicals and mild processes that could be used to avoid the high absorbable organic halogen compounds (AOX) load and damage to the environment from the waste of wool plants. In this research, we sought to achieve a new zero‐AOX processing alternative to conventional processes such as chlorine/Hercosett processing and thus use environmentally friendly enzymes and chitosan as a biopolymer. We studied enzymatic, oxidative, and additive processes and various combinations of them to improve the shrink‐proofing and antifelting properties of wool. We performed our experiments with enzymatic treatments using commercial protease preparations, such as Perizym AFW, Alcalase 2.5L, Savinase 16L, and papain. The oxidative agents were hydrogen peroxide and sodium hypochloride, and the additive agents were based on polyurethane, polysiloxane, and silicone, as well as chitosan, a hydrophilic and natural polymer. We attempted to determine the agent or combination that best improved the shrink‐proofing properties. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2903–2908, 2004     

Impact of extreme donor age on the outcome of living-related donor kidney transplantation

Eosinophil cationic protein (ECP) in sputum may be used to estimate the severity of bronchial inflammation and obstruction in asthmatics as well as to monitor asthma drug therapy. For this purpose, standardized processing of sputum is important. The aim of our study was to determine whether time and temperature influence the ECP concentration in the sputum of asthmatics. The samples of induced sputum obtained from 12 patients with stable asthma were homogenized using ultrasonification, and centrifuged. Supernatants were evenly divided and stored for 1, 6, 24 or 72 h at either 4 or 25 degrees C, then frozen at -80 degrees C. The ECP concentrations were determined using fluoroimmunoassay and compared with the immediately frozen samples. After storing at 4 degrees C, the ECP levels at the four time points were 101.2, 96.0, 98.2 and 90.6% of the initial concentration, respectively. When sputum specimens were stored at 25 degrees C, ECP levels decreased to 96.1, 94.4, 90.7 and 87.7%, respectively. The influence of time on ECP concentrations in sputa was statistically significant (p=0.02). A significant temperature effect was found when comparing the specimens stored at 4 degrees C with those at 25 degrees C (p=0.03). Looking at individual time points, a significant decrease in ECP concentration was only seen at 25 degrees C after 24 and 72 h. We conclude that eosinophilic cationic protein in the sputum of asthmatics decreases in a time- and temperature-dependent process. If sputa cannot be processed after obtaining the specimens, they should be stored in a refrigerator at 4 degrees C, until eosinophilic cationic protein is measured.     

Effect of Processing Parameters on Flocculation of Picochlorum oklahomensis

The flocculation process is commonly used to separate suspended solids from water. The microalgae strain, Picochlorum oklahomensis (PO), was investigated for its flocculation characteristics. Efficiencies of biopolymer addition, pH adjustment and electroflocculation for biomass recovery from the culture medium were examined. Flocculation efficiency of PO increased sharply above pH 11 and reached 97 % at pH 13. Chitosan was more effective in flocculating PO cells than sodium alginate and cationic starch. A generalized linear mixed model using a beta distribution for response was utilized for optimization of the chitosan flocculation process variables. Biomass: chitosan ratio, pH and settling time (ST) were the independent variables. There were significant 3-way interactions among the variables. The highest PO flocculation efficiency, 98.4 %, was obtained at biomass: chitosan ratio of 2.78, pH 9 and ST of 12 h. The electroflocculation efficiency improved with increasing current, operation time (OT) and ST. The highest electroflocculation efficiency, 99.74 %, was obtained under the following conditions; 0.8 A (ampere) and 15 min and 12 h, OT and ST, respectively. This study demonstrated that pH adjustment, chitosan addition and electroflocculation were all technically viable methods to flocculate PO cells. However, selection of the most suitable technique and the optimum treatment conditions needs to be based not only on the application of algal biomass, but also on an economic feasibility study.     

Poly(acridine orange)-modified glassy carbon electrodes: electrosynthesis,characterisation and sensor application with uric acid

Poly(acridine orange) was electropolymerised on glassy carbon electrodes by potential cycling in phosphate buffer solution at pH 5.5, 6.0, 7.0 and 8.0. Electrochemical behaviour of the modified electrodes was studied by cyclic voltammetry in phosphate buffer solution at various pHs and found that the best polymer film formation was obtained at pH 5.5. Quantitative determination of uric acid was achieved by cyclic voltammetry, differential pulse voltammetry (DPV) and fixed-potential amperometry in phosphate buffer solution at pH 5.5. Anodic peak currents were linearly proportional to concentration of uric acid in the range 1–75 µM for cyclic voltammetry, 0.4–75 µM for DPV and 0.04–5.3 µM for amperometry. Detection limits were 3.7 × 10^?1, 9.7 × 10^?2 and 9.5 × 10^?3 µM for cyclic voltammetry, DPV and amperometry, respectively. The modified electrodes exhibited good sensitivity, wide linear range and good stability. There is no interference from substances commonly present in natural samples.     

Tocopherol,phytosterol and phospholipid compositions of genetically modified peanut varieties

Genetic engineering offers great potential for developing peanut cultivars resistant to a broad spectrum of pathogens that pose a recurring threat to peanut health. In an effort to improve the disease resistance of peanuts, three transgenic peanut lines were developed. Somatic embryos of the peanut cultivar Okrun were transformed by inserting a chitinase gene from rice and/or a β‐1‐3‐glucanase gene from alfalfa. The main objective of this research project was the assessment of composition of the nutritionally beneficial bioactive components in biotechnology‐derived peanut lines. The transgenic peanut lines 188, 540 and 654, which showed increased resistance to fungal diseases, as compared to the parent line, were analyzed for their tocopherol, phytosterol and phospholipid compositions. The compositions of transgenic lines were compared to those of the parent cultivar. The experimental results indicate no major changes in the composition of transgenic peanut lines examined in this study with respect to the cultivar Okrun. Copyright © 2005 Society of Chemical Industry     

Change in proximate, amino acid and fatty acid contents in muscle tissue of rainbow trout (Oncorhynchus mykiss) after cooking

Changes in proximate, amino acid and fatty acid composition of farmed, commercially important rainbow trout (Oncorhynchus mykiss) after conventional and microwave cooking were analysed. Rainbow trouts cooked in microwave ovens had statistically significant higher total protein, total fat, and ash than electrical oven‐cooked samples. The amounts of essential and nonessential amino acids were not different between cooking methods, but the difference between raw and cooked samples was significant. Lysine, leusine, methionine, threonine, valine, arginine and histidine were found most in microwave‐cooked rainbow trouts whereas isoleucine, tyrosine and phenylalanine were found most in electrical oven‐cooked samples. As total saturated fatty acid and total monounsaturated fatty acids amount were not statistically different between the cooking methods, the difference between raw and cooked fillets was found statistically significant (P < 0.05). There was no statistically significant difference between raw and cooked fillets in total n‐3 and n‐6 contents.