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981.
Nicola M Schreurs Michael H Tavendale Geoffrey A Lane Tom N Barry Nicolas López‐Villalobos Warren C McNabb 《Journal of the science of food and agriculture》2007,87(6):1076-1087
The objectives of this work were to establish the effect of seven different forages with a varied condensed tannin (CT) content, plant maturity and nitrogen fertiliser application on the ruminal formation of skatole and indole using an in vitro method designed to mimic rumen fermentation conditions. After 10 h of incubation, the concentration of indole and skatole was highest when incubating white clover (P < 0.05). Polyethylene glycol addition, to inhibit CT, showed that CT significantly reduced the formation of indole and skatole when incubating Lotus corniculatus, sulla, Dorynium rectum and Lotus pedunculatus (P < 0.01). Mature forage growth resulted in a significantly lower concentration of indole and skatole being formed in vitro compared to the incubation of new spring growth (P < 0.001). A higher application of nitrogen fertiliser to perennial ryegrass‐based pasture resulted in a higher crude protein concentration in the plant and a significantly higher concentration of skatole formed in vitro (P < 0.001). Forages containing CT reduced the conversion of endogenous protein to indole and skatole and plants containing a higher CT concentration tended to be more effective, but compositional differences of CT between forages may also have had an influence. New forage growth or swards that had a high application of nitrogen fertiliser promoted the formation of indole and skatole. Copyright © 2007 Society of Chemical Industry 相似文献
982.
Beer production with up to 40% unmalted cereals such as barley, wheat, rice and maize is legally allowed and thus practised in many European countries. The use of oats and sorghum as brewing adjuncts has great potential for creating new beer types/flavours and saving costs. In contrast to oats, sorghum is not as well known within Europe; however, its versatility makes it a very promising crop for exploitation in these temperate‐zone regions. This review describes the brewing‐relevant characteristics of unmalted oat and sorghum grain, investigates the role and properties of endogenous/exogenous enzymes during mashing, discusses the processability/quality of mashes, worts and beers produced with up to 40% oat or sorghum adjunct, and examines the effectiveness/limitations of endogenous enzymes as well as the benefits of the application of exogenous enzymes. Copyright © 2014 The Institute of Brewing & Distilling 相似文献
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Birgit Bittmann Rebeca Bouza Luis Barral Mar Castro‐Lopez Sonia Dopico‐Garcia 《Polymer Composites》2015,36(11):2051-2058
Biopolymers are gaining increasing interest because of decline of mineral oil reserves, increasing waste problem, and increasing consciousness of society for environmental problems. However, competitiveness of biopolymers compared with conventional plastics is still limited due to partly insufficient properties and high prices. This study investigates the influence of blending of poly(hydroxybutyrate‐co‐hydroxyvalerate) (PHBV) with poly(butylene adipate‐co‐terephthalate) (PBAT) as well as the influence of addition of functionalized montmorillonite (OMMT) to the blends on morphology and thermal behavior. Dispersion state and morphology of the nanocomposites are studied by X‐ray diffraction as well as scanning electron microscopy. Thermal stability is studied by thermogravimetric analysis and crystallization behavior is studied by differential scanning calorimetry and polarized optical microscopy. With respect to the morphology for the blends it can be seen that the immiscible biopolymers PHBV and PBAT are distributed in interlocking zones. There is a good dispersion and homogeneous distribution of OMMT within the biopolymer blends. The addition of 50% or more PBAT to PHBV as well as the insertion of OMMT enhances thermal stability of PHBV. In the blends, the addition of PBAT retards crystallization of PHBV. The OMMT acts as nucleating agent leading in total to more but less perfect crystals in the blends, and the crystallization slows further due to constraint in the movement of polymer chains. These results contribute to the understanding of the structure–properties relationship of bionanocomposite materials for packaging applications. POLYM. COMPOS., 36:2051–2058, 2015. © 2014 Society of Plastics Engineer 相似文献
985.
Nadja Looser Drazen Kostelac Ellen Scherbaum Michelangelo Anastassiades Hubert Zipper 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2006,386(5):135-141
Within the framework of food surveillance a total number of 593 conventionally grown strawberry samples mainly originating
from Germany, Spain, Italy and Morocco were analysed for pesticide residues at the Chemisches und Veterin?runtersuchungsamt
Stuttgart between 2002 and 2005 using the QuEChERS multiresidue method. Pesticide residues were detected in 98% of the samples
and 93% of all strawberry samples were found to contain multiple pesticide residues. The German or EU-harmonised MRLs were
exceeded by 54 strawberry samples (9%) with mepanipyrim being the most frequently violative compound. The average total concentration
of pesticides per sample was 0.41 mg/kg which is similar to the average value for fruits in general, with Italian products
containing the highest and the German ones the lowest residue concentrations. A general trend observed was the decline of
the total pesticide residue concentration as the harvest season is progressing.
For more efficient analysis, the spectrum of pesticides to be targeted in instrumental analysis was regularly being adjusted
to include compounds that are relevant for strawberry samples. The information was extracted from the internet database Pesticides-
Online. In total, 105 different pesticide compounds were identi- fied with 65% of the positive residue findings being < 0.05 mg/kg
and 96 of them being < 0.5 mg/kg. Fungicides were much more often detected than insecticides and herbicides with cyprodinil,
fludioxonil, fenhexamid, tolylfluanid and azoxystrobin being the most frequently detected compounds together accounting for
50% of the total detections. A toxicological risk assessment with the emphasis on multiple residues was performed using the
results obtained for the strawberry samples. 相似文献
986.
Köber R Daus B Ebert M Mattusch J Welter E Dahmke A 《Environmental science & technology》2005,39(19):7650-7655
The bulk of arsenic (As) at contaminated sites is frequently associated with iron (hydr)oxides. Various studies ascribe increasing dissolved As concentrations to the transformation of iron (hydr)oxides into iron sulfides, which is initiated by dissolved sulfide. We investigated whetherthis processes can be utilized as a source treatment approach using compost-based permeable reactive barriers (PRB), which promote microbial sulfate reduction. Arsenic-bearing aquifer sedimentfrom a contaminated industrial site showed a decrease in As content of <10% after 420 days of percolation with sulfide-free artificial groundwater. In contrast, water that had previously passed through organic matter and exhibited sulfide concentrations of 10-30 mg/L decreased As content in the sediment by 87% within 360 days. X-ray diffraction showed no arsenic sulfides, but XANES spectra (X-ray absorption near edge structure) and associated linear combinations revealed that adsorbed arsenate of the original sediment was in part reduced to arsenite and indicated the formation of minor amounts of a substance that contains As and sulfur. The speciation of dissolved As changed from initially As(V)-dominated to As(III)-dominated after sulfide flushing was started, which increases the mobility of As. Because sulfide can be supplied not only by compost-based PRBs but also by direct injection, sulfide flushing has a wide range of application for the source treatment of arsenic. 相似文献
987.
Teixeira GH Durigan JF Santos LO Hojo ET Cunha Júnior LC 《Journal of the science of food and agriculture》2011,91(15):2844-2849
BACKGROUND: Jaboticaba (Myriciaria jaboticaba (Vell) Berg.) is a highly perishable Brazilian berry with a shelf life of only 2 days under ambient conditions. Low temperatures and controlled atmosphere (CA) have been used to extend the shelf life of perishable fruit. Thus the aim of this study was to determine the effect of CA with varying concentrations of oxygen (1, 5, 10, 15 and 21kPa) during cold storage (12.5 °C) of ‘Sabará’ jaboticaba fruit. RESULTS: Atmospheres with lower oxygen concentrations (1 and 5 kPa O2) significantly reduced jaboticaba respiration rate. Fruit stored under these conditions had higher L* values, and titratable acidity (TA), and lower ratios of soluble solids content (SSC)/TA. However, at the lowest concentration of oxygen (1 kPa O2), firmness decreased markedly compared to fruits stored at higher O2 levels (P < 0.05). After only 2 days of storage at ambient temperature jaboticaba received a score of 1.6 (dislike strongly ? 1) compared to fruit stored under CA, which scored 7.4 (like moderately ? 7). After 9 days of storage, fruit from all treatments remained above the limit of acceptability (score 5) and were rated as 6.2. With respect to appearance, statistical differences between treatments were not observed. The total anthocyanin content was not affected by oxygen concentration but decreased 40.4% during CA storage. CONCLUSION: 'Sabará' jaboticaba fruit can be satisfactorily stored under atmospheres containing 5‐21 kPa O2 at 12.5 °C for up to 6 days. Copyright © 2011 Society of Chemical Industry 相似文献
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