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关键词： Royal jelly   Growth kinetic parameters   Dairy dessert   Probiotic bacteria  

摘要： Royal jelly (RJ) is attractive functional food due to health promoting effect and rich nutrient content. The aim of this study was to produce a probiotic dairy dessert (Keskul) at an optimal RJ dose which is no adverse effect on physicochemical, rheological, sensory properties and functionality of the product. Initially, the growth parameters of Lactobacillus plantarum, Lactobacillus rhamnosus and Bifidobacterium animalis subspp. lactis in presence of RJ (0.001-10.0 mg/mL) were evaluated with Gompertz model. Then, the experimental (100 mg/mL) and estimated (56 mg/mL) Minimum Inhibitory Concentration (MIC) of tested probiotic bacteria were determined according to predictive microbiology approach. Among probiotics, L. plantarum was found distinctively proper for producing dairy dessert with RJ. In this study, a new dairy dessert was developed consisting of RJ and L. plantarum. The control, including probiotic (D1), probiotic and RJ (1 mg/mL) (D2), probiotic and RJ (5 mg/ mL) (D3) were analyzed during shelf life of dessert. The combination of L. plantarum with RJ (1 mg/mL) provided probiotic properties (>6 log CFU/g) and limited the mold count. Thus, the dairy dessert developed in this study may be a good alternative to innovative functional food using RJ with acceptable sensorial attributes.

关键词： Critical Micelle Concentration   Mixed Micelles   Detergency   Foaming   Clouding   Gibbs Monolayer  

摘要： Critical micelle concentration (CMC) is a fundamental physical parameter of surfactant aggregation in solution. The CMC is determined by different methods, tensiometry, conductometry, microcalorimetry, fluorimetry, and so on. However, it is known that though CMC is reported as a single value, in reality, micelle formation occurs over a narrow range of concentration for different experimental procedures produce different results. We shall discuss about a unique procedure of measuring correct CMC applicable to all potential methods used in practice. This is essential for the evaluation of thermodynamic properties of the micelle forming process in pure and mixed states in terms of solution theories. As we in this short documentary want to deal with various aspects of Milton Rosen's research-wherein we have also worked-a few other facets of surfactant chemistry research, besides the micelle formation, are also briefly discussed. In mixed surfactant systems, synergistic effects in various surfactant properties like detergency, foaming, solubilization, and so on are found whereas in some others non-synergistic effects are observed. Dehydration of micelles with an increase in temperature or by the addition of hydrophilic substances may cause clouding to the system. Soluble amphiphilic systems produce Gibbs monolayer at the air/water interface;insoluble amphiphiles form Langmuir monolayers. A documentary of the above aspects will be herein presented and discussed. We mention that this article is neither an original research article nor a review article. This is a mixture of the two: a documentary of both original research and some review of our works presented in memory of Prof. Milton Rosen.

关键词： Median particle size   Gastrointestinal digestion   Ovariectomy-induced osteoporosis   Bone mineral density   Bone turnover markers   Ovariectomized rats  

摘要： As a kind of promising resource, animal bone has been widely processed into functional foods. However, there is little research about the effect of particle size on the physicochemical properties and digestibility of yak bone powder (YBP), as well as its anti-osteoporosis activity. In this study, the YBP with median particle sizes (MPS) ranging from 19.68 to 128.37 mu m were prepared, and their digestibility and anti-osteoporosis activity were investigated. The results showed that smaller MPS significantly increased water holding capacity and protein solubility without changing composition. The MPS reduction greatly promoted protein digestion, producing more peptides<3 kDa and free amino acids while decreased Ca2+ and P5+ release during gastrointestinal digestion. The in vivo results revealed the positive effect of YBP on ovariectomy-induced osteoporosis in rats. The bone mineral density of ovariectomized (OVX) rats was obviously improved by regulating bone turnover markers (B-ALP, OCN, S-CTX, ES and TRAP), thus potentially shedding light on osteoporosis remission. However, different MPS exhibited a weak effect on osteoporosis in OVX rats. Therefore, YBP could be produced in relatively large particle size without sacrificing food sensory quality, the processing time of which could also be shortened for higher productivity and lower cost.

关键词： Skimmed milk   Drying   Spouted bed   Physicochemical properties   Optimization  

摘要： In the present research, the influence of the inlet parameters of a laboratory spouted bed (inlet air temperature and milk flow rate) on the physical properties (moisture content, wettability, dispersibility, particle size and density), chemical properties (protein, cholesterol, and triglyceride content) and morphology of the milk powder was evaluated and compared with properties of the commercial spray dried powder. The effect of these two inlet parameters was significant on all of the physical and chemical properties. Particle morphology of the spouted bed dried samples (flat, solid, and irregular) was entirely different from commercial spray dried milk powder (spherical, and hollow). The optimum values of the inlet air temperature and milk flow rate, calculated by RSM, were obtained 80 degrees C and 2.8 ml/min, respectively. The small error between properties predicted by the models and the experimental data indicated that the performed optimization was satisfactory.

关键词： annealing   digestibility   Castanopsis sclerophylla   starches  

摘要： Annealing is a hydrothermal treatment that changes the structural and functional properties of starches. This study investigates and compares the effects of one-step annealing for 24 and 48 h, respectively, and two-step annealing on the structural, physicochemical, and digestive properties of Castanopsis sclerophylla starch (CaS). Annealing has no effect on CaS morphology, crystalline pattern, and short-range ordered structures. However, annealing decreases the swelling power, solubility, setback, and peak viscosity of CaS and increases its crystallinity and thermal stability. Post annealing, the rapidly digestible starch (RDS) of CaS decreases, the slowly digestible starch (SDS) increases while the resistant starch (RS) content of CaS remains unchanged. Comparing with One-step annealing for 24 h, one-step annealing for 48 h and two-step annealing does not further change the RDS and SDS content of annealed CaS.

关键词： Plasma treatment   surface modification   immobilize   tissue engineering   biomaterial  

摘要： In this study, polyurethane (TPU) scaffolds were fabricated using freeze-drying technique and gelatin macromolecules immobilized on the activated surface by oxygen plasma treatment. Scanning electron microscopy (SEM) micrographs indicated an interconnected porous microstructure with randomly oriented pores. According to the results, the diameter of pores increased after plasma treatment and gelatin grafting. Fourier transform infrared spectroscopy illustrated that there is no inappropriate interaction between materials during processing;furthermore, attenuated total reflection Fourier transform infrared spectroscopy confirmed the immobilization of gelatin molecules on the surface of the plasma-treated polymeric scaffolds. Waterdrop contact angle analysis presented that wettability and hydrophilicity of constructs increased after grafting gelatin on the activated surface. Phosphate-buffered saline absorption and hydrolytic biodegradation enhanced after surface modification of the polymeric samples. Cellular behavior demonstrated better adhesion and spreading after grafting gelatin of oxygen plasma-treated constructs. No evidence of toxicity was observed for 7 days. DNA content determined that the number of viable cells increased in TPU-gelatin matrixes after 1 day in contrast with TPU scaffolds. Based on results, oxygen plasma treatment can create an activated surface to graft gelatin macromolecules and achieve optimum physicochemical, mechanical, and biological features for the neo-tissue formation.

关键词： Fluidized bed roasting   Hot air impingement   Flavour compounds   Ginsenoside   Extraction yield  

摘要： This study aimed to improve the availability of red ginseng lateral roots by applying air jet impingement fluidized bed roasting as a novel processing technology. The effects of air temperature (150 degrees C, 160 degrees C, 170 degrees C, 180 degrees C, 190 degrees C, and 200 degrees C) on the physicochemical properties and flavor compounds of red ginseng lateral roots were investigated. The air roasting time and velocity of the jet impingement fluidized bed roaster were 10 min and 21.68 m s-1, respectively. The moisture content and bulk density significantly decreased, while the total weight loss, expansion index and specific volume significantly increased as the temperature increased (p < 0.05). The extraction yields significantly increased by 38.34% at 200 degrees C compared with unroasted samples (p 0.05). The high-temperature roasted sample had larger and more porous structures on their surfaces than the unroasted sample in the scanning electron microscope images. The major ginsenosides (Re, Rg1, Rb1, Rc, Rb2 and Rd) peaked at 150 degrees C or 160 degrees C, whereas the minor ginsenosides (Rh1 and Rg2) peaked at 190 degrees C or 200 degrees C. Furfural and maltol increased 444 and >10 times in the roasted samples at 200 degrees C and 170 degrees C, respectively, when compared with the unroasted samples.

关键词： Coal gasification fine ash   Particle size   Physicochemical properties   Wettability  

摘要： Coal gasification, recognized as one of the most effective coal utilization technologies, will produce a cer-tain amount of fine ash during the high-temperature reaction process. The wettability of gasification fine ash is a critical parameter to characterize the degree of high-temperature reaction and determine the separation efficiency of purification process. In the present work, the effect of physicochemical properties on the wetting behavior of different gasification fine ash is studied. The difference in wettability between particle size and types can be explained by the unique properties of particles (i.e. pore structure, mineral composition, and chemical structure). The results show that with the decrease in particle size, the surface morphology transforms from an irregular shape with a rough surface to a spherical shape with a smooth surface. The pore structure, characterized by fractal surface dimension Ds, presents positive correlations with the contact angle for a single type of fine ash. The mineral composition can just qualitatively assess the hydrophilicity of particles. Only the ratio of hydrophilic chemical structure can be used as a generic parameter to describe the wetting performance. Meanwhile, the wettability of hydrophilic particles can be enhanced by increasing moisture content, but there is no significant effect of moisture content on the wettability of hydrophobic particles. (C) 2021 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. All rights reserved.

关键词： Antibacterial   antioxidant   fractional ethanol precipitation   physicochemical   polysaccharide   Sargassum pallidum  

摘要： Three polysaccharides (SPP-30, SPP-60 and SPP-90) were fractionated from Sargassum pallidum by 30%, 60% and 90% (v/v) ethanol, successively. Their physicochemical properties, antioxidant and antibacterial activities of SPP-30, SPP-60 and SPP-90 were comparatively investigated. The results showed that three polysaccharide fractions contained different neutral sugar, protein, uronic acid and sulphate contents. SPP-30 had the highest molecular weight (3.77-206.73 kDa), followed by SPP-60 (5.55-189.44 kDa) and SPP-90 (4.92 kDa). SPP-30, SPP-60 and SPP-90 were composed of fucose, arabinose, galactose, glucose, xylose and mannose but with different molar ratios. Scanning electron microscopy analysis suggested that they had different surface morphology and sizes of fragmentation. In vitro antioxidant assays suggested that SPP-30 and SPP-90 exhibited stronger scavenging activities against DPPH, ABTS and hydroxyl radicals than SPP-60. Moreover, SPP-30 and SPP-60 exhibited antibacterial activities against Staphylococcus aureus, while SPP-90 exhibited moderate antibacterial activity against both Staphylococcus aureus and Escherichia coli.

关键词： Sonication   Anthocyanin   Color density   Total phenolic content   Pasteurization  

摘要： Pomegranate juice (PJ) is a well-known nutritional drink that has been widely consumed due to its health benefits. However, sedimentation of polyphenol, browning, and contamination of microorganisms are problems of fresh juice. This research aimed to evaluate the effect of ozone and ultrasound treatment on pasteurization and disinfection of PJ. The effective parameters have been optimized by response surface methodology. The optimized ozone dose was 3.5 ppm (2 L/min O-2 flow, UV power of 1.0 A) for 6 min. The amplitude level of 50% and 6 s of on/off pulse in 5 min was achieved as an optimized state for the ultrasound. Selected conditions yielded: 1760.51 mg GA/L of TPC, 72.47 mg C3G/L of TAC, 0.47 g citric acid/L of TA, 14.24 degrees Brix of TSS, 0.683 of BI for ozone gas, and 1678 mg GA/L of TPC, 72.31 mg C3G/L of TAC, 0.47 g citric acid/L of TA, 14.5 degrees Brix of TSS, 0.743 of BI for sonication. The ultrasonic and ozone treatment of PJ contaminated with Escherichia coli PTCC 1399, aerobic bacteria, and fungi resulted in 100% and 2% disinfection, respectively. The application of ultrasound as a disinfection technique has reduced microbial load with the lowest effect on physicochemical data of PJ.