摘要:

AbstractThe bark and the stem of unretted jute plant (Corchorus capsularis) were found to contain various free, glycosidic and ester‐linked phenolic acids. From an 80% aqueous ethanol extract,p‐coumaric, ferulic, caffeic, vanillic andp‐hydroxybenzoic acids were identified and quantified.p‐Coumaric acid, the major component, and β‐sitosterol were isolated and cha

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371002

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractSewage sludges containing high concentrations of zinc, copper and nickel were added separately to samples of two soils, a silty clay loam and a sandy loam, on which pH levels between 4.5 and 7.5 had been established; there were also treatments with sludge of low metal content or no‐sludge. Soil‐sludge mixtures were either continuously cropped with ryegrass or kept uncropped in pots in the glasshouse for 6 months. Zinc and nickel concentrations in 0.1 μM calcium chloride extracts of soils from the cropped pots and in solutions displaced from the fallow pots decreased with increasing pH over the range tested, but copper concentrations remained steady above pH 5.5; individual metal concentrations in ryegrass tops followed the same pattern with pH as those in extracted solutions. Squared correlation coefficients (R7) between shoot metal concentrations and concentrations of metals in EDTA, DPTA or calcium chloride extracts or displaced solutions, when taken over all soil, pH and sludge treatments, were>0.60 (P<0.001). Ryegrass yield reductions occurred on soils contaminated with each of the three metal sludges when soil pH was 5.5 or b

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371003

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractAn experiment was conducted over three consecutive seasons during 1982 and 1983 with the objective of evaluating the effects of traffic‐induced compaction on soil physical properties of an Alfisol for no‐till and ploughed systems. Main treatments of the split plot design consisted of disc ploughing to a depth of 200 mm followed by harrowing compared with no‐seedbed preparation. Compaction treatments of none, two and four passes of a 2‐tonne roller were the sub‐plots. The roller was 60 cm in diameter, 180 cm long, with a contact area of 0.1729 m2and was pulled by a 33.6 kW tractor. Compaction treatments were applied 2 to 3 days before seeding. Four passes increased the penetrometer resistance of the soil surface, and bulk density; and as a result there were significant reductions in total porosity, saturated hydralic conductivity, infiltration rate and the amount of water released between 0.1 and 100 kPa suctions. Two passes of the roller had small and non‐significant effects on soil properties. The effects of vehicular traffic in terms of increasing soil compaction became progressively severe with repeated compaction in subsequent seasons. Compaction affected soil properties in the 0–100 mm depth layer only, and was more evident following ploughing than following no‐

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371004

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA study was made of the role of plant and microbial enzymes in the major nitrogenous changes during ensilage. Perennial ryegrass was ensiled directly, after gamma‐irradiation, and after inoculation of the sterile grass with homofermentative lactobacilli. Plant enzymes mainly were responsible for proteolysis, whereas amino acid metabolism was the result of microbial activity. Inoculation reduced proteolysis: this was considered to be a result of rapid acidification.Lactobacillus plantarumandStreptococcus faecaliswere shown to be non‐proteolytic species with a limited ability to catabolise amino acids. Substantial quantities of water‐soluble carbohydrates were made available during ens

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371005

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe following are summaries of the papers presented to a joint meeting of the Agriculture, Food and Oils and Fats Groups of the Society of Chemical Industry, held on 11 March 1986 at the Society of Chemical Industry, 14–15 Belgrave Square, London SW1X 8PS. The papers published here are entirely the responsibility of the authors and do not reflect the views of the Editorial Board of the Journal of the Science of Food and Agricultur

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371006

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractGreen malt, partially dried, was processed by high‐temperature short‐time (HTST) extrusion cooking at three different temperatures. Volatile components of the product were analysed by gas chromatography (g.c.) using a headspace sampling technique, and identified by mass spectrometry (m.s.). The concentration of pyrazines increased when the temperature was increased from 130 to 160°C, but it fell at 190°C, probably as an effect of volatilisation. However, the influence of parameters such as water content, the milling of the raw material and its residence time in the extruder must also be taken into account. Extruded malt contained more total pyrazines than conventionally processed malt. 2‐Vinyl‐5‐methylpyrazine and 2‐vinyl‐6‐methylpyrazine were found only in extruded malt, especially at high processing temperature. The pyrazine content per colour unit was high, an observation which may lead to the production of a more flavourful beer

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371007

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe poor nutritional performance of rats fed raw soya‐bean‐containing diets appeared to be due to reduced apparent digestion and absorption of dietary protein, coupled to changes in systemic metabolism leading to a poor overall nitrogen balance. Aqueous heat treatment greatly reduced but did not eliminate the antinutritional effect. Heat treatment with aqueous ethanol was more effective. The whey protein (pH 4.8 soluble extract) fraction contained the bulk of the trypsin inhibitor and haemagglutination activity and gave the poorest net protein utilisation value. However, an eight‐fold increase in trypsin inhibitor content did not significantly effect apparent nitrogen digestibility. Therefore inhibition of gut proteolytic enzyme activity invivoby soya bean trypsin inhibitors did not account fully for the poor nutritional performance. The problems elicited by soya bean are not transitory and thus there was a cumulative deterioration in overall performance for 16 weeks as a result of continuous exposure to soya

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371008

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe junctions between the muscle fibres and the connective tissues of the myocommata in the spotted trevalla (Seriolella punctataForster) were investigated by scanning electron microscopy. In prerigor muscle, the fine collagen fibrils which arise from the myocommata to form the muscle cell envelope were evident. After the fish were stored several days in ice, progressive deterioration was observed in these fibrils. The structure and the degradation was similar in nature to that reported previously in blue grenadier.

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371009

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractA method is described for the rapid determination of amino acids in liquid foods by high‐performance liquid chromatography (h.p.l.c.). The method has proved itself simple and reliable in use and is intended to provide amino acid profiles within 30–40 min of receipt of sample. Method assessment is discussed and the results obtained on typical processed foods are presen

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371010

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY

摘要:

AbstractThe hydrolysis products of soyasaponins in legumes and of pure standards have been examined using t.l.c., g.c. and g.c.‐m.s. Interrelationships between eight soyasapogenols, produced under conditions of aqueous or non‐aqueous acid hydrolysis have been established. The significance of the work to the analysis of soyasaponins is discus

ISSN:0022-5142    

DOI:10.1002/jsfa.2740371011

出版商:John Wiley&Sons, Ltd    

年代:1986

数据来源: WILEY