Texturization of Sweetened Mango Pulp: Optimization using Response Surface Methodology

Sugar added mango pulp was texturized with alginate. To optimize both the mechanical properties and thermostability of the products, an experimental design was used combined with response surface methodology. Alginate concentration was the major factor affecting mechanical properties of texturized pieces with higher strength as the gelling agent concentration increased. Furthermore, gel strength and thermostability generally increased as calcium and glucono-δ-lactone concentrations, and/or heat treatment duration increased. As large quantities of sweetened pulp were used, texturized pieces with high dry matter content and good flavor qualities were obtained.     

Sequencing Analysis of a 36·8 kb Fragment of Yeast Chromosome XV Reveals 26 Open Reading Frames Including SEC63, CDC31, SUG2, GCD1, RBL2, PNT1, PAC1 and VPH1

The complete sequence of a 36 775 bp DNA segment located on the right arm of chromosome XV of Saccharomyces cerevisiae has been determined and analysed. The sequence encodes 26 open reading frames of at least 100 amino acids. Eight of these correspond to known genes, whereas 18 correspond to new genes. The sequence has been deposited in the EMBL databank under Accession Numbers: Z75154, Z75155, Z75156, Z75157, Z75158, Z75159, Z75160, Z75161, Z75162, Z75163, Z75164, Z75165, Z75166, Z75167, Z75168, Z75169, Z75170, Z75171, Z75172, Z75173, Z75174, Z75175, Z75176, Z75177, Z75178, Z75179. © 1997 John Wiley & Sons, Ltd.     

Liposomes as Proteinase Carriers for the Accelerated Ripening of Saint-Paulin Type Cheese

The possibility of accelerated cheese ripening through addition of liposome entrapped proteinase to milk was investigated. Both enzyme encapsulation rate in liposomes and their retention in cheese were evaluated with multilamellar vesicles (MLV) and reverse-phase evaporation vesicles (REV). Using REV in Saint-Paulin type curd, no nitrogen loss was observed to the whey due to the added enzymes in liposomes. In cheese, REV produced a more progressive proteolysis during ripening than MLV did. REV addition did not lead to texture defects. Bitterness development, a critical defect in enzyme added cheese, could be delayed and minimized using REV.     

The near field of an antenna surrounded by a dielectric with two teeth

The near field of an antenna surrounded by a dielectric with two teeth is studied when the ambient medium is dissipative. We use the continuity of radial power flux and the boundary conditions at each interface, but not near the discontinuity, to express this field.     

Sintering Characteristics of Rare-Earth Oxides

The sinterability of europium, samarium, gadolinium, and dysprosium pure oxides was investigated at various temperatures under both oxidizing and reducing conditions as well as hot pressing. Data are presented on the density, grain size, thermal expansion, resistance to water corrosion, and the microhardness of these oxides. Photomicrographs showing grain growth and microstructure are included. The results indicate that dysprosium oxide is the most stable of the four oxides investigated. It sinters with small grain size, is similar to alumina in coefficient of thermal expansion, and does not undergo a phase transformation.     

SOLUBILITY AND DIFFUSIVITY OF GASES IN AN ORGANIC SOLUTION OF AMINE

Solubilities and diffusivities of carbon dioxide and nitrous oxide in a mixture of toluene and isopropanol organic solution of cyclohexylamine were measured at 20°C in the range of pressures of solute from 1 to 3 bars. This was performed with an original chromatographic technique taking into account the presence of the product of the reaction.     

An ethanol spray at veraison enhances colour in red wines

Aqueous ethanol (5% v/v) was sprayed onto bunches of Vitis vinifera L. cv. Cabernet Sauvignon 8–9 weeks following full flowering (controls were sprayed with water). Internal ethylene concentration in treated berries increased to a maximum within 6 hours, and berry colour subsequently increased substantially (maximum attained 2–3 weeks after spraying). Berry fresh weight at harvest was unaffected by ethanol treatment, but wine made from treated grapes showed greater colour intensity compared with control grapes.     

Deciphering the ability of different grapevine genotypes to accumulate sugar in berries

Background and Aims: To analyse the genetic determinants of berry sugar content in grapevine varieties, a method that combined measurements of total soluble solids (TSS) from berries sampled at a fixed stage after veraison with data on the yield and the leaf area was tested. Methods and Results: Over three seasons, differences in TSS at harvest for Riesling and Gewurztraminer grapes were explained by differences in the veraison dates and in the fruit‐to‐leaf ratios. TSS, yield and leaf area were also evaluated for 120 genotypes, which were progeny from a cross between Riesling and Gewurztraminer. Thermal timescales (degree‐days) proved relevant for describing sugar accumulation in the parent varieties, and when berries were sampled at a fixed heat sum after veraison in the progeny, the genotypic variability of sugar content was considerably reduced compared with the measurements on the same date at the end of the season. A negative relationship between the fruit‐to‐leaf ratio and the sugar content was also detected in the progeny. Conclusions: The evolution of TSS during berry ripening can be described using thermal timescales. Additionally, information on the yield and the leaf area needs to be integrated to analyse the behaviour of genotypes. Significance of the Study: A method to characterize the genotypic effect on fruit sugar accumulation after eliminating the contribution of veraison dates and crop load was proposed.     

POLYMERIZATION OF BUTADIENE IN TOLUENE WITH NICKEL(II) STEARATE-DIETHYL ALUMINUM CHLORIDE CATALYST†

A bench-scale batch reactor was used to study the polymerization of butadiene with nickel(II) stearate Et₂AlCl catalyst. In particular, the effects of moisture on polymerization were investigated. The initiation reaction is sensitive to temperature. At 0°C an induction period was observed, but at room temperature initiation can be assumed instantaneous. Water enhances catalytic reactivity, however at water concentrations greater than 10 mmol/L, termination reactions become significant. Maximum conversion is obtained in the 6 to 15 mmol/L range of water. The determining step for the molecular weight of polymer is the chain transfer to monomer. At low H₂O concentration the molecular weight increases with water concentration, however it becomes independent of water concentration at high moisture content. With the help of statistical analysis of the experimental data, a two-active-species model was developed to describe the kinetics of the system and to explain certain polymerization characteristics.     

Retention of Cobalt, Cesium, and Strontium in the Hydrates of C3S, C3A, and Gypsum

The retention of cobalt, cesium, and strontium as trace elements in the hydrates of simple ordinary portland cement components has been investigated. The combined characterization of the solid by SEM, electron microprobe, XRD, and SIMS, as well as the chemical analysis of the solutions, allowed us to identify the likely localization of these trace elements in the solid. In particular, cobalt is dramatically incorporated into the solid during the hydration of C₃S; we show that this is due to the formation of a cobalt oxychloride, a compound which is unstable at temperatures ≥60°C. Cesium is retained in small amounts in the C-S-H and CH mixture. The formation of hydrated aluminates notably increases its retention. Finally, small quantities of strontium are also retained in silicates and, in the presence of gypsum, its retention is markedly higher. This is likely due to the formation of sulfoaluminates.