Advanced Materials Research Vols. 1033-1034

Abstract: A bionanocomposite was cast using Ni, TiO₂ and ZnO nanoparticles stabilized by soluble starch (nanoNi, nanoTiO₂ and nanoZnO) as filler in a glycerol plasticized-pea starch (GPS) matrix. Fourier-transform infrared spectroscopy (FT-IR) and transmission electron microscopy (TEM) results show that nanoparitlces were about 20 nm. In GPS/nanoparticles nanocomposites, loading a low level of nanoparticles improved the mechanical properties. When the nanoparticle content varied from 0 to 4 wt%, the tensile yield strength containing nanoNi, nanoTiO₂ and nanoZnO from 2.08 to 4.05, 8.23 and 11.31 MPa; Young’s modulus increased, from 22.3 to 89.1, 212.6 and 243.5 MPa respectively. The improvement in these properties may be attributed to the interaction between the nanoparticle filler and GPS matrix.

Abstract: To detect Ciprofloxacin (CPFX) residues in food stuffs of animal origin rapidly by immune method, preparation of high quality polyclonal antibody against CPFX was the most critical step of project. We produced two kinds of antigens for CPFX, using carrier protein bovine serum albumin (BSA) and ovalbumin (OVA) by a modified carbodiimide method, and then the hapten-protein conjugates were characterized by ultraviolet spectrophotometry in detecting qualitatively comparable hapten density, before being used for the immunization and detection purposes. The production of polyclonal antibodies (PcAbs) were sought following the generation of appropriate CPFX-BSA conjugate. One PcAb against Ciprofloxacin (CPFX) was produced and the titer polyclonal antibody could reach 6.25×105. In the optimized ELISA, the PcAb showed 50% inhibition at 10.93 ng/mL for CPFX in buffer.

Abstract: The flame atomic absorption method was applied to determine aluminum in jellyfish. The optimum detecting conditions were determined through many experiments. It established a nitric oxide-acetylene flame atomic absorption method to detect aluminum content in jellyfish that a good linear relationship is obtained in concentration range and correlation coefficient r²=0.9996. There are no significant differences in results after jellyfish samples were digested by three pretreatment methods. The detection limit of this method is 3.5 mg/L, the relative standard deviations are less than 5%, and the recovery is in the range of 88.50~104.20%. The test shows that: both the precision and accuracy accord with the demands, so this instrument analytical method could apply to research on quantitative detection of aluminum in jellyfish.

Abstract: Extracting dihydromyricetin from Ampelopsis grossedentata by water extraction method. The orthogonal test and single factor experiment were used to optimize the best extraction condition. The ratio of liquid and material is 20:1, extraction time is 90min, extraction temperature is 90°C,holding time is 1d. The results of comparison between two purification methods show: Purify with acetone and recrystallization with water is better. The purity of dihydromyricetin is high to 98%, recovery rate was 59.2%.

Abstract: The mold strains with stronger ability producing aroma were screened from 15 mold strains of the laboratory, and the culture conditions were optimized. The result showed: the strains njsys-6, njsys-45, njsys50 had stronger ability producing aroma. In koji juice medium, the strains had the most abundant metabolites, the esterifying enzyme activity and total ester content were the highest for 7.19U/mL and 0.18%. Njsys-45 could resistant high concentration ethanol and temperature up to 10% and 36°C respectively, it could resistant pH3.6. It had been confirmed that njsys-45 strains could be added aroma substances in Koji, and the esterifying enzyme activity was 7.18U/mL, the total ester was 0.18%.

Abstract: The peroxide value, content of malondialdehyde were selected as evaluation index to meusure the oxidation stability of algae oil. In this study, we investigated the effect of the temperature, light, air and metal ions on oxidation stability of algae oil. The results showed that higher was the temperature, much lower was the oxidation stability of oil; Light and oxygen both greatly promoted the oxidation of the oil; the order of the influence for metal ions to the oxidation stability was:Cu²⁺>Zn²⁺>Fe²⁺. Hence, we get that we should produce or store the oil under the condition that out of light, air, metal ions and kept at lower tempreture.

Abstract: The instant ready-to-eat oyster was prepared through hot water cooking, seasoned, dried, vacuum packed and sterilized. The optimal seasoning formula was as follows: sauce 10.0%, sugar 9.0%,vinegar 10.0%,rice wine 4.0%. The product has rich nutrition and special seafood flavor, comfortable texture and easy to eat. Ready-to-eat the oyster snack food processing technology research offered a new way to develop high value-added products and technical support.

Abstract: The influence of temperature and pH on solubility, water-holding capacity (WHC) and stability of polypeptide from camellia seed meal were studied. The polypeptide was extracted from camellia seed meal by trypsin after ultrasonic pretreatment, with a degree of hydrolysis (DH) of 21.69%. At this DH, the camellia seed meal polypeptide (CSMP) has better solubility and WHC with a proper higher temperature or when its pH deviates from the isoelectric point. Moreover, the CSMP would not agglutinate in alkaline range even though it is heated to 121°C, and after storing under the condition of -18°C for a month, it would not precipitate after thawing. The results show that the CSMP has great solubility and WHC in both acidic and alkaline conditions, as well as good thermal stability and freezing storage stability in alkaline range.

Abstract: Solid-phase microextraction (SPME) is a rapid sample preparation in volatile analysis. The aromatic volatile compositions of ‘Kuerle’ were analyzed using SPME and gas chromatography-mass spectrometry (GC-MS). The effect of different types of fibers, extraction time, and extraction temperature on the volatile results were compared and discussed. The results were as followed. Results showed that 65μm PDMS/DVB fiber had the best effect of extraction. The optimum factors such as extraction time and temperature were 45 min and 40°C.

Abstract: Volatile compositions of fresh tilapia and fishy odour development in the muscle during 12 days of storage at-18°C were studied. Investigations were carried out to extract the volatile compounds in tilapia using solid phase microextraction (SPME). A total of 35, 35 and 38 volatile components were identified in the muscle, head and skin of tilapia, respectively, within which nonanal, octanal and E-octenal were the most powerful contributors to the fishy odour of Tilapia. During iced storage, free fatty acid (FFA) content, conjugated diene (CD) and thiobarbituric acid reactive substances (TBARS) increased. Peroxide value (PV) gradually decreased after increasing in the first 3days of storage. Total volatile basic nitrogen (TVBN) values increased from 7.7 to 24.1 mg/100g after the storage of 12 days. Correlations between chemical indexes and sensory evaluation scores showed that the off-odour in fish muscle was mostly governed by lipid oxidation.