bluuebunny/crossref_metadata_2025_split huggingface dataset:
Response of some black tea quality parameters to nitrogen fertiliser rates and plucking frequencies
Authors: Owuor P Okinda , Odhiambo Herman O 
Published: November 2006

AbstractThe effects of the rate of application of nitrogenous fertiliser and frequency of plucking (harvesting) on various black tea quality parameters and yields were compared on done 6/8. High rates of nitrogen application and long plucking intervals reduced the theaflavin content and brightness of black tea liquor. The caffeine content of the black tea increased with increasing rates of nitrogen application but decreased with increase in the plucking interval. The Group I volatile flavour compounds increased with nitrogen application rate and long plucking intervals while the Group II volatile flavour compounds and the flavour index decreased. Tasters preferred teas from shorter plucking intervals and low rates of nitrogen application. Yields increased with increasing rates of nitrogen but were lowered by long harvesting intervals. The rate of nitrogen application did not change the distribution of leaf into different standards.
Effect of pH on the colour formed by Fe‐phenolic complexes in ripe olives
Authors: Brenes Manuel , Romero Conceptión , García Pedro , Garrido Antonio 
Published: November 2006

AbstractThe effects of the pH in the flesh of ripe olives processed for table olive production, the type of acid used to correct it, the heating process used and the iron content of the flesh on the colour of the final product were studied. The best colour was obtained by bottling the fruits at pH 7. Additions of acids, especially citric acid, always caused discoloration when olives were bottled at a pH of around 7. On the other hand, when the fruits were packed at a pH higher than 7 the addition of certain amounts of acids produced darker olives. Darker colours are related to higher iron contents in the flesh, but treatment of olives with ferrous gluconate before neutralising the pH of the flesh yielded better colours than those treated after neutralising for the same iron concentration in the olives. Results obtained after adding iron to the oxidation solutions did not show the same pattern as those obtained using fruits. These results suggest that the fixation of the colour formed is not only due to the phenol‐iron complexes.
The influence of seed size on digestibility and growth performance of broiler chickens fed full‐fat rapeseed
Authors: Liu Yong‐Gang , Jensen S K , Eggum B O 
Published: November 2006

AbstractTwo double low rapeseed varieties were separated into small and big seeds to study their nutritive value for broiler chickens. The seed weights for small and big seeds of spring rape variety Jaguar were 3.6 and 4.9 mg, and of winter rape Impala were 4.1 and 5.3 mg, respectively. Analytical results showed no significant differences in protein and fatty acid content between the big and small seeds. The small seeds contained more fibre constituents, eg lignin 13.7% higher for Jaguar and 3.4% higher for Impala, the other dietary fibre components show ed a similar trend. The big seeds, however, tended to be higher in fat and gross energy, but also in total glucosinolates. A 2 × 2 × 3 factorial design was performed on 24 broilers, to investigate the apparent digestibility and growth performance during three successive periods of balance trials, using diets consisting of 350 g kg−1 full‐fat rapeseeds and 650 g kg−1 remainder feed mixture identical for all treatments. The diets with big seeds clearly showed higher digestibility for all measured dietary components. The surpluses as absolute percentage units respectively for dry matter were 2.8 (P < 0.001); gross energy 3.8 (P < 0.001); fat 7.9 (P < 0.001) and protein 1.6 (P = 0.045). The same trend was also found in the digestion of fatty acids and vitamin E. The big seeds displayed 7% higher (P = 0.071) growth rate and 8% higher (P = 0.002) feed conversion, respectively. Greater nutritional superiority of the big seeds was observed on the earlier growth ages, indicating the young birds are more sensitive to the seed size difference. It is concluded that the big seeds are more digestible than the small seeds and that a selection towards Digger seed size or a mechanical separation during processing will be beneficial.
Kinetics of the decolouring of carotenoid pigments
Authors: Minguez‐Mosquera M Isabel , Jaren‐Galan Manuel 
Published: November 2006

AbstractThe decolouring reaction of carotenoids was studied using β‐carotene, di‐esterified capsanthin and capsanthin. The study was designed to determine what effects the increase in temperature, the nature of the reaction medium and the presence of light have on the kinetics of the reaction. The reactions that take place in an anhydrous medium follow a zero‐order kinetics, while those that take place in an aqueous medium follow a first‐order kinetics. Light and temperature accelerate the degradation reaction without changing the formal aspects of the reactions. The values for the thermodynamic parameters (activation energy and enthalpy of activation) of each reaction were different according to the conditions used, but this variation was due to a compensation effect. However, the existence of this effect confirms that the decolouring reaction is the first step of the carot‐enoid degradation, and this step is identical for all of the pigments irrespective of the reaction conditions, although the formal aspects and kinetics of this first step are strongly modulated by the nature of the pigment and the experimental conditions used.
A mycological survey on mixed poultry feeds and mixed rabbit feeds
Authors: Bragulat M Rosa , Abarca M Lourdes , Castellá Gemma , Cabañes F Javier 
Published: November 2006

AbstractThe mycoflora of 55 samples of mixed poultry feed and mixed rabbit feed were studied. Differences in the mycoflora between the two kinds of feed were studied. Fungal counts ranged from < 10 2 to 10 5 cfu g−1, the lowest counts being in the samples of rabbit feeds. Seventy‐three fungal species belonging to 28 genera were identified. The predominant species were Aspergillus flavus, A candidus, A amstelodami, Penicillium chrysogenum and Fusarium moniliforme. Aphanocladium album, ranking sixth in the samples overall, showed exceptional incidence compared with published data. Fusarium moniliforme, A flavus and A amstelodami had the highest individual percentage counts. The F. moniliforme and A candidus percentage counts were significantly higher in mixed poultry feeds than in mixed rabbit feeds, quite the reverse of the A amstelodami and P chrysogenum percentage counts.
The effect of leaf protein concentrate from red clover on plasma cholesterol level in rats
Authors: Szymczyk Beata , Gwiazda Stanislaw , Hanczakowski Piotr 
Published: November 2006

AbstractThe effect of native and defatted leaf protein concentrate (LPC) from red clover on plasma cholesterol level in rats was studied. Fat‐free casein was used as a control protein. The native LPC contained 212 g kg−1 of ether extract and oleic acid (C18: 1) was its main fatty acid. LPC protein was relatively poor in sulphur‐containing amino acids. Each protein studied was given to rats with or without soya bean oil. It was found that total cholesterol level in plasma of rats fed with the oil‐containing diets was higher than that of rats fed with the oil‐free diets. Original fat present in the native LPC though rich in unsaturated fatty acids had no hypocholesterolaemic effect. LPC was hypocholesterolaemic compared with casein in diets not containing added soya bean oil, although the difference did not reach statistical significance.
Rapid detection of polymorphism in yams (Dioscorea sp) through amplification by polymerase chain reaction and rDNA variation
Authors: Muzac‐Tucker Ingrid , Ahmad Mohammed H 
Published: November 2006

AbstractRibosomal DNA (rDNA) from rice (Oriza Sativa) was used to examine polymorphism in 12 yam (Dioscorea sp) cultivars. Restriction enzyme digests of total yam DNA was probed with the pRR217 probe containing the entire repeat unit of rDNA from rice. The polymerase chain reaction was also used to amplify genomic DNA of six of the 12 cultivars studied using random primers. The amplification patterns of D rotundata‐cayenensis cv tau suggested that ‘tau’ is more closely related to D rotundata sp than it is to the D cayenensis sp. The results showed polymorphisms among the different yam cultivars.
The relation between yield and protein in cereal grain
Authors: Simmonds Norman W 
Published: November 2006

AbstractAn analysis of published data on genetic relations between dry grain yields (y, t ha−1) and protein content [p, protein as a fraction (g g−1) of dry grain] of cereals is presented. In all, 106 usable regressions of y on p across geneotypes were assembled. The long‐recognised negative relation between yield and protein concentration was fully substantiated. There is a strong positive relation between grain yield and protein yield. The linear regression coefficient of yield on protein concentration is related to yield, with slope about −15. This relation holds approximately over all cereals. The data can be used to estimate a characteristic parameter described by C = dy/d(yp) = ∼ 15–25 at the mean of each experiment. The relationship is surprisingly consistent but no simple physiological interpretation is available. In discussion, the high C, the impact of strong negative regressions of y on p for breeding strategies, the fact that protein yield increases with gross grain yield but at falling p and certain socio‐economic consequences are emphasized. An acute need for orderly reporting of experimental data is also emphasised; the existing literature is chaotic as to units, moisture contents and conversion factors.
Silk maysin content and resistance of commercial corn [maize] hybrids to kernel contamination by aflatoxin
Authors: Widstrom Neil W , Snook Maurice E , Wilson David M , Cleveland Thomas E , McMillan William W. 
Published: November 2006

AbstractSeveral phenols and related compounds have been shown to have detrimental effects on insects while others have antibiotic activity against fungi which attack higher plants. Insects have also been implicated as contributors to preharvest contamination of corn [maize], Zea mays L, by aflatoxin. The objectives, therefore, were to determine (a) if commercial corn hybrids vary in their silk maysin content and aflatoxin contamination of the grain, and (b) if grain aflatoxin contamination is correlated with maysin and related compounds. During 4 years of testing, 16 corn hybrids varied significantly for silk maysin content and grain aflatoxin contamination. Based on correlations, grain aflatoxin content of the hybrids tested was not significantly associated with maysin, chlorogenic acid, and 3′‐methoxymaysin contents. It was concluded that other untested phenolic compounds in the category of compounds analyzed in the present study could be involved in resistance to aflatoxin formation, and that other classes of compounds should also now be assessed to locate major chemical resistance components.
Red clover extracts inhibit legume proteolysis
Authors: Jones Beth A , Muck Richard E , Hatfleld Ronald D 
Published: November 2006

AbstractUnwilted red clover and alfalfa herbage were hand‐chopped, inoculated, ensiled into laboratory silos and opened after 0, 1, 3 and 7 days. Proteolysis was 40% lower with the red clover silage than alfalfa silage after 7 days of ensiling. The lower extent of proteolysis with the red clover silages could not be explained by differences in dry matter content, pH decline nor final pH of the silage. It was determined that red clover has a buffer soluble protein that could inhibit proteolysis in red clover and alfalfa. The soluble protein is possibly a polyphenol oxidase.
Relationship between laser‐induced fluorescence intensity and crude palm oil quality
Authors: Tan Yew Ai , Chong Chiew Let , Low Kum Sang 
Published: November 2006

AbstractCrude palm oil quality is an important consideration in the production of refined palm oil of consistent high quality. The quality of crude palm oil is determined by the analysis of oxidative and hydrolytic parameters such as peroxide value, anis dine value, free fatty acid content and moisture and impurities, all very time consuming and counter‐productive for both crude palm oil mills and refineries to carry out. This study shows that laser‐induced fluorescence (LIF) analysis can be used as an alternative to analysing all the common oxidative and hydrolytic parameters mentioned. LIF at 673 nm was indicative of the oxidative quality of crude palm oil. There was also positive correlation between fluorescence intensity and the carotene and the deterioration of bleach ability index of crude palm oil, and the Rancimat induction time of the final refined product.
Biodegradation of plant cell walls, wall carbohydrates, and wall aromatics in wheat grown in ambient or enriched CO2 concentrations
Authors: Akin Danny E , Rigsby Luanne L , Gamble Gary R , Morrison W Herbert , Kimball Bruce A , Pinter Paul J , Wall Gary W , Garcia Richard L , Lamorte Robert L 
Published: November 2006

AbstractMature internodes from wheat (Triticum aestivum L) grown in control (ambient at c 370 μnol mol−1) or enriched (to 550 μmol mol−1) concentrations of atmospheric CO2 in the free‐air CO2 enrichment (FACE) system were analyzed for potential changes in biodegradation of constituents due to predicted increases in atmospheric levels of CO2. The first internodes below the grain were incubated with the lignocellulose‐degrading white rot fungus, Phanerochaete chrysosporium K‐3, or incubated without microorganisms. Plant samples were then analyzed for dry weight loss, disposition of specific cell types to biodegradation using electron microscopy, carbohydrates and lignin using solid state NMR spectroscopy, and ester‐and ether‐linked aromatics using gas chromatography. Phanerochaete chrysosporium extensively degraded stems cells (c 75%) and both carbohydrate and aromatic portions of the wheat stems; proportionately more carbohydrates were removed by the fungus from the stems. Enriched CO2 did not affect the chemical composition of wheat stems or the biodegradation by P chrysosporium of plant cell walls or wall components for the most part. Data from various methods all indicated that enriched CO2 did not substantially alter the biodegradation of wheat cell wall internodes or wall components. Evidence was not found for an influence on C cycling due to CO2 concentrations in this study.
Trypsin inhibitory activity of raw soya bean after incubation with rumen fluid
Authors: Susmel Piero , Spanghero Mauro , Marchetti Stefano , Moscardini Stefano 
Published: November 2006

AbstractFour soya bean (Glycine max Merr) inbreds, two of which (Williams 82 and Amsoy 71) capable of synthesising the Kunitz trypsin inhibitor (high trypsin inhibitory activity (TIA)) and two (L81–4590 and L83–4387), nearly isogenic to the former but lacking this particular function (low TIA) were used. In‐vitro trials were performed to evaluate the residual TIA of flours incubated with runem fluid and the possible effect of proteinase inhibitors on rumen microbial fermentation, estimated by gas production. Only a slow fall in TIA was observed after short incubation times (5–10% at 2 h and 10–18% at 6 h), but after this period the rate of decline of TIA accelerated to give residual TIA of about 50% after 12 h and undetectable values after 48 h. Significant differences between genetic backgrounds were observed only at 2 h, when the Williams 82 background had a faster initial loss of TIA (89.1 versus 97.5% of the original activity, P < 0.01). Different patterns of TIA degradation were observed according to the presence/absence of the Kunitz inhibitor: inbreds lacking the Kunitz inhibitor initially had a higher residual TIA (95.9 versus 90.7%, P < 0.01) while at 12 and 24 h the residual TIA was considerably lower with respect to the other inbreds (45.4 versus 60.8 and 10.7 versus 20.4, respectively, P < 0.01). Gas production after 2 and 6 h of incubation was similar across treatments, whereas slightly but consistently more (P < 0.05) gas was produced at longer incubation times for inbreds lacking the Kunitz inhibitor. The results indicated that the proteinase inhibitors contained in raw soya bean are degraded at a much slower rate than previous nylon bag studies have suggested and that the presence of the Kunitz inhibitor leads to a higher residual TIA after rumen degradation and slightly lower microbial gas production.
Creating typical jagged force‐deformation relationships from the irregular and irreproducible compression data of crunchy foods
Authors: Ulbricht Diane , Normand Mark D , Peleg Micha 
Published: November 2006

AbstractThe irregular jagged force‐deformation relationships of two snacks stored at nine levels of relative humidity were used to create typical‐averaged relationships by a special mathematical procedure developed on the basis of the statistical properties of random sequences. The typical force‐deformation relationships so created were practically indistinguishable from the original experimental ones from which they were derived. In principle, they can be used to identify conditions where textural changes take place and to establish criteria for textual classification of samples by visual comparison.
Microbial and sensory quality of vegetables for soup packaged in different atmospheres
Authors: Manzano Marisa , Citterio Barbara , Maifreni Michela , Paganessi Mario , Comi Giuseppe 
Published: November 2006

AbstractFresh prepacked vegetables for soup have become very popular on the Italian market, since they are already peeled, cut, washed and ready‐to‐use. The packaging and the modified atmosphere can prolong their shelf‐life and maintain their hygienic, physicochemical and sensory characteristics during storage at + 4°C. The hygienic and sensory quality was evaluated by analysing microbial growth and atmosphere composition at the moment of packaging and at the end or the shelf‐life of vegetables prepacked in air on under modified atmospheres, and by determining the browning or blackening of parsley and the loss of carrot exudates. A large number of different groups of microorganisms was found in raw vegetables. In spite of this high starting concentration of microbial flora, the prepackaging systems investigated did not seem to significantly influence their growth during vegetable storage at +4°C. No pathogenic microorganisms were isolated from the prepackaged vegetables. The hygienic quality was similar in all packaging systems used. However, the vegetables packaged in perforated. film kept their sensory characteristics better than those packaged in air or under a modified atmosphere.
Sensory evaluation of bitterness and astringency of 3R(−)‐epicatechin and 3S(+)‐catechin
Authors: Thorngate J H , Noble A C 
Published: November 2006

AbstractBitterness and astringency of the monomeric flavan‐3‐o!s ( + )‐catechin and (−)‐epicatechin were rated using time‐intensity (T‐I) methodology. Three concentration levels (0.5. 0.9 and 1.2 g liter−1) oi each compound were assessed, and the parameters time to maximum intensity (TMAX), intensity at the maximum (IMAX) and total duration (TTOT) were extracted from the T‐I curves. No differences in TMAX for either bitterness or astringency were found between these chiral isomers or as a function of concentration within a compound. Epicatechin had a significantly higher bitter IMAX than catechin at all three concentration levels, and had a significantly longer TTOT at the two higher concentrations. Epicatechin was more astringent than catechin. but this was only significant at one concentration. Astringency TTOT was longer for epicatechin, although this was nonsignificant at the lowest concentration. The three concentrations of catechin were significantly different for both bitterness and astringency IMAX and TTOT. Epicatechin showed evidence for the astringency response plateauing above the 0.9 g litre−1 level. n‐Propylthiouracil status had no effect on perception of either bitterness or astringency.
Microbial decontamination of black pepper by ozone and the effect of the treatment on volatile oil constituents of the spice
Authors: Zhao Jian , Cranston Peter M 
Published: November 2006

AbstractThe use of ozone as a substitute for ethylene oxide to decontaminate whole black peppercorn and ground black pepper and the effects of ozone on the volatile oil constituents of the spice were studied. Black peppercorns were immersed in water and sparged with ozonised air (ozone concentration, 6·7 mg litre−1) for 10 min at an air flow rate of 6 litre min−1. This treatment reduced the microbial population of peppercorn by 3–4 log numbers. Ground black pepper with various moisture levels was sparged with ozonised air for up to 6 h. This treatment reduced the microbial population by 3–6 log numbers, depending on the moisture content of the spice. Higher moisture content led to a greater reduction in microbial load. The volatile oil constituents of the spice with and without ozone treatment were extracted with isopropyl ether and analysed by gas chromatography and gas chromatography‐mass spectrometry. Ozone treatment of ground black pepper resulted in the oxidation of certain volatile oil constituents while the treatment had no significant effect on the volatile oil constituents of whole peppercorn.
Breakdown of peptides from a soya protein hydrolysate by rumen bacteria. Simultaneous study of enzyme activities and of two physico‐chemical parameters: Molecular weight and hydrophobicity
Authors: Depardon Nathalie , Debroas Didier , Blanchart Gerard 
Published: November 2006

AbstractBreakdown of soya peptides by an inoculum of ruminal mixed bacteria was studied in vitro. Peptides were hydrolysed at 75% after 5 h. The dipeptidyl‐aminopeptidase type 1 (DAP‐1), exoaminopeptidase and leucine aminopeptidase (LAP) activities were measured using GlyArg‐MNA, Ala‐pNA and Leu‐pNA as substrates, respectively. While the total proteolytic activity remained stable throughout peptide breakdown, the DAP‐1 already present at the beginning of fermentation was multiplied by two. This peptidase activity is a major index for the presence of Prevotella ruminicola. The exoaminopeptidase activity increased during the exponential phase of bacterial growth. A peak of LAP activity was observed after 3 h of incubation. This activity which was associated to the production of lactate after 3 h suggested the Streptococcus bovis was present in the environment. Measuring by high‐performance liquid chromatography (HPLC) gel filtration the size of peptides during their breakdown showed that high‐molecular‐weight peptides (4000–5000) were apparently more rapidly broken down relative to intermediate peptides (2000–3000) and to small assimilable peptides (1000–500). Separation of soya peptides by reverse‐phase HPLC showed a disappearance of hydrophilic and hydrophobic peptides. This study showed that there is no preferential breakdown of hydrophilic peptides relative to hydrophobic peptides in vitro.