The effect of hydrothermic treatment on the physicochemical properties of rye grain

Summary The gelatinized, autoclaved and sodiumhydroxide-treated starch preparations were used and their interaction with soluble pentosans and gliadin was analysed. The molecular sieving technique and optical methods were used to detect the complexes formed. The modified starches formed complexes with both soluble pentosans and gliadin in acidic and neutral media (non-ionic molecular forces being involved). The autoclaved starch showed the highest reactivity. The amylose and amylopectin played different roles in the interactions and the aggregates of amylose with gliadin and amylopectin with soluble pentosans were the prevailing forms present in the complexes. Small quantities of other products were also identified.

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Einfluß der hydrothermischen Behandlung auf die physiko-chemischen Eigenschaften des RoggenkornsII. Wechselwirkung der Eiweiß-und Kohlenhydratkomplexe (Modelluntersuchung)

Zusammenfassung Die Wechselwirkungen verkleisterter, autoklavierter und mit Natronlauge behandelter Stärke mit löslichen Pentosanen und Gliadin werden mit Hilfe der Gelpermeation und mit optischen Methoden untersucht. Die modifizierten Stärken bildeten Komplexe mit den Pentosanen und mit Gliadin im sauren und neutralen Medium, autoklavierte Stärke zeigte die hächste Reaktion. Die unterschiedliche Rolle von Amylose und Amylopection zeigte vorherrschend Amylose-Gliadin und Amylopectin-PentosanKomplexe, während andere Komplexe in kleineren Mengen auftraten.

     

Properties of amidated pectins. I. Preparation and characterization of amidated pectins and amidated pectic acids

The preparation of high molecular weight pectic acids with varying degrees of amidation (15–61%) is described. The samples are characterized by analytical parameters, viscosity and behaviour on gel permeation and ion-exchange chromatography columns. Results show that the monomer composition is not changed and that aggregation may occur in aqueous solution of highly amidated pectic acids.     

Hermetic storage for control of common bean weevil,Acanthoscelides obtectus (Say)

This study evaluated hermetic storage as a method of controlling Acanthoscelides obtectus (Coleoptera: Chrysomelidae: Bruchinae) in stored beans. Recently harvested “vermelhinho” cultivar of the common red bean was used, which had already been infested by A. obtectus in the field. Beans with a moisture content of 15.0% wet basis were stored in silo bags (3 kg), plastic bottles (1.5 L), or non-hermetic glass containers (3 L) (control) for 120 days. The packages were stored in an acclimatized chamber at 25 °C with a relative humidity of 70 ± 5%. At time intervals of 0, 30, 60, 90, and 120 days, three packages of each treatment were opened, and analyses were performed to assess the infestation percentage by insect pests, moisture content, density, electrical conductivity, germination percentage, and cooking time. There was no increase in infestation by A. obtectus in the grains stored in the silo bags and plastic bottles during the 120 days of storage; however, there was a significant increase in infestation in the grains in non-hermetic storage (control). The quality of the beans correlated with infestation; it was not altered in the hermetic storage systems and decreased in the control sample. Hermetic storage of common beans is an effective tool in the control of A. obtectus.     

The effect of Acetobacter sp. and a sulfate-reducing bacterial consortium from ethanol fuel environments on fatigue crack propagation in pipeline and storage tank steels

This paper evaluates the effects of microbiologically influenced corrosion (MIC) on fatigue-crack growth of candidate materials useful in expanding bio-ethanol usage, including a storage-tank steel (ASTM A36) and two pipeline steels (API 5L X52 and X70). The microbiological species sampled and cultivated from an ethanol fuel production stream are responsible for both acetic acid and hydrogen sulfide production that lead to significant increases in fatigue-crack growth rate across a wide range of stress-intensity-factor amplitudes (ΔK). The mechanism for increased fatigue damage is hydrogen uptake through adsorption into the steel, which embrittles material ahead of the growing fatigue crack.     

Selected Saccharomyces cerevisiae yeast strains and accurate separation of distillate fractions reduce the ethyl carbamate levels in alembic cachaças

Ethyl carbamate (EC) is a potentially toxic compound that may be present at concentrations above maximum limits established in alcoholic beverages, such as cachaça. Most traditional alembic cachaça is produced on a small scale using empirical knowledge. The fermentation step is conducted using yeasts that are endogenous to the sugar cane, and the distillation process is relatively uncontrolled. In this study, gas chromatography coupled with mass spectrometry was used to determine the EC levels in distillate musts and fractions produced by spontaneous or selected Saccharomyces cerevisiae strains. The aim was to verify the influence of selected strains as starters for fermentation compared with spontaneous fermentation on EC formation. The distillate fractions from these two production processes were also analysed. Our results demonstrated higher levels of EC (which surpass the limits defined by Brazilian law) in cachaças produced by spontaneous fermentation (50%) compared with the selected strains (30%); and the distillation step showed great contribution for the reduction of the compound. From must to distillate fractions we found an average decrease on EC levels of 62% using selected strains and 44% for the spontaneous fermentation. In addition, careful separation of the distillation fractions was crucial for producing high-quality and safe beverages.     

Holistic environmental soil-landscape modeling of soil organic carbon

In environmental soil-landscape modeling (ESLM), the selection of predictive variables is commonly contingent on the researchers' domain expertise on soil–environment processes. This variable selection strategy may suffer bias or even fail in regions where the process knowledge is insufficient. To overcome this problem, this study demonstrates a holistic ESLM framework which consists of five components: model conceptualization, data compilation, process identification, parsimonious model calibration, and model validation. Based on the STEP-AWBH conceptual model, a comprehensive pool of 210 potential environmental variables that exhaustively cover pedogenic and environmental factors was constructed. This was followed by strategic variable selection and development of parsimonious prediction models using machine learning techniques. The all-relevant variable selection successfully identified the major and minor factors relevant to the SOC variation, showing that the major factors important for explaining SOC variation in Florida were vegetation and soil water gradient. Topography and climate showed moderate effects on SOC variation. Parsimonious SOC models developed using four minimal-optimal variable selection techniques and simulated annealing yielded optimal predictive performance with minimal model complexity. The holistic ESLM framework not only provides a new view of selecting and utilizing variables for predicting soil properties but can also assist in identifying the underlying processes of soil-environment systems of interest. Due to the flexibility of the framework to incorporate various types of variable selection and modeling techniques, the holistic environmental modeling strategy can be generalized to other environmental modeling domains for both prediction and process identification.     

江苏单二啤酒大麦麦芽麦汁中混浊物质的研究

对江苏单二啤酒大麦麦芽麦汁中混浊物质成分进行了研究,结果表明多糖是麦汁混浊的主要成分,含量为82.57%,其次为蛋白质和多酚。采用离子交换色谱技术对混浊物质中的糖类进行了研究,结果表明糖类物质的单糖组成以葡萄糖为主,其次为半乳糖、阿拉伯糖、木糖。采用SDS-PAGE电泳结合基质辅助激光解析飞行时间串联质谱(MALDI-TOF/TOF)对麦汁混浊物质中蛋白质组分进行了鉴定,结果表明蛋白质分子量主要分布于25~45ku及小于18.4ku的两个部分,且主要来自于麦芽水溶蛋白及醇溶蛋白,质谱分析表明混浊蛋白主要为AMY2/BASI复合体A链,此外还有少量的Z4蛋白、大麦醇溶蛋白γ3、油体钙蛋白2及BTI-CMe2.1。本研究结果对于改良江苏啤酒大麦及其麦芽品质具有指导借鉴意义。