bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between the in vivo digestibility of hay and its solubility in pepsin–hydrochloric acid and fungal cellulase solutions
Authors: Adamson Alan H. , Terry Geoffrey R.
Published: October 2006

The determination of the solubility of the organic matter (OM) of hay in pepsin‐hydrochloric acid and fungal cellulase solution according to the method of Jones and Hayward1 gave reproducible results when applied to four hays with solubilities of 51.5, 49.1, 63.5 and 40.2%. In addition the correlation of the soluble OM determined by the cellulase solubility technique and in vivo digestibility studies for 34 hays produced highly significant correlations for the digestibility of the OM in the dry matter (DM) (r=0.91, RSD ± 2.180) and the OM digestibility (r=0.91, RSD ± 2.362). These data indicate that the determination of the solubility of OM in fungal enzyme solution is an acceptable method for the prediction of in vivo digestibility of the OM in the DM of hays.
The uptake and distribution of copper in perennial ryegrass and white clover grown in flowing solution culture with a controlled supply of copper
Authors: Jarvis Stephen C.
Published: October 2006

The uptake and distribution of copper was examined in perennial ryegrass and white clover when these were grown in flowing solution culture with a controlled supply of copper at 0.025 mg litre−1 (0.4 μM). Although the concentration of copper in the shoots of white clover was greater than that in those of ryegrass, there was no difference between the two species in (i) absorption per unit of root or (ii) the transport of copper from roots to shoots. Differences in the growth patterns of the two plants may be responsible for differences in copper concentration in their dry matter. The proportion of the shoot's copper that was associated with cell walls fell, during growth over 33 days, from 23 to 12% in ryegrass and from 35 to 7% in white clover. There was some indication that terminating the supply of phosphate to the plants (which did not affect absorption by roots or transport to shoots) may have increased the degree of association of copper with the cell walls of the shoots.
The effect of fermentation temperature on the quality parameters and price evaluation of Central African black teas
Authors: Cloughley John B.
Published: October 2006

Tea was fermented at 15, 25 and 35°C and otherwise manufactured according to commercial practice on several occasions in early May and mid‐November 1977. Fermentation at 15°C resulted in teas containing greater amounts of the desirable theaflavin class of pigments. Teas produced at the higher temperatures contained more of the thearubigin pigments, including the polymeric fraction known as the non‐dialysable material. Colour development was also more rapid at 25 and 35°C. Teas produced at the low temperature were accorded higher evaluation and a linear relationship between evaluation and theaflavin content was established which explained > 70% of the variation in value data. It is suggested that, since the price premium for quality is high and the market stable, the installation of temperature control equipment to regulate the production of oxidation products would improve the quality of the product and benefit Central African tea industry.
Phenolic constituents of mesophyll and non‐mesophyll cell walls from leaf laminae of Lolium perenne
Authors: Harris Philip J. , Hartley Roy D. , Lowry Katharine H.
Published: October 2006

trans‐Ferulic acid was the main phenolic constituent released when walls of mesophyll and non‐mesophyll cells from leaf laminae of Lolium perenne L. were treated with sodium hydroxide. cis‐Ferulic, trans and cis‐p‐coumaric, p‐hydroxybenzoic and diferulic acids were also present. Mesophyll and non‐mesophyll cell walls contained similar amounts of ferulic acid (approximately 6 mg g−1 cell wall), but mesophyll walls contained only small amounts of p‐coumaric acid (0.4 mg g−1 cell wall) compared with those of non‐mesophyll (3 mg g−1 cell wall).
A gas chromatographic method for the determination of pentosans
Authors: Folkes David J.
Published: October 2006

A method for the determination of pentosans by gas chromatographic analysis of furfural produced by acid treatment is presented. Samples are treated with 3.85m hydrochloric acid and the furfural produced partitioned in situ into di‐butyl ether. Furfural is measured by gas chromatography with acetophenone as internal standard. The method is calibrated against xylose which is taken through an identical hydrolysis procedure. When applied to starch and flour samples, the method showed good precision with a coefficient of variation of 2–4% depending upon sample type.
Methods for methionine and cyst(e)ine determination. A comparison between two institutes
Authors: Chavana Suparath , Haque Azizul , Njaa Leif R. , Pettersen Jan
Published: October 2006

Methods for determination of sulphur‐containing amino acids in protein concentrates were compared between two institutes. Methionine determined by gas‐liquid chromatography and colorimetrically by iodoplatinate gave comparable results. For cyst‐(e)ine three modifications of liquid chromatography determination after performic acid oxidation, one determination with a cysteine specific ninhydrin reagent and one determination based on transforming cyst(e)ine‐S to cadmium sulphide and atomic absorption determination of cadmium, were compared. It is concluded that the best which can be hoped for in a cyst(e)ine method is to obtain results which may be used for comparisons within a laboratory.
The effect of low level exposure to dietary cadmium, on cadmium, zinc, copper and iron contents of selected tissues of growing lambs
Authors: Dalgarno Alexander C.
Published: October 2006

Twenty‐four, 13–14 week pregnant Cheviot ewes were offered either a basal grass cube diet containing 0.3 mg cadmium (Cd) kg−1, or the same diet supplemented with Cd to give dietary Cd contents of 3.4 or 6.4 mg Cd kg−1. Increasing dietary Cd had no effect on numbers of viable offspring or mean birth weight of lambs. After weaning, some of the lambs were maintained on the same diets as their respective dams for approximately 280 days. Increased dietary Cd had no effect on food intake or carcass weight at slaughter. The liver zinc content of lambs consuming the diet with the highest Cd content declined significantly. Increasing the dietary content of Cd decreased the retention of copper by the liver. At slaughter, Cd could not be detected in blood nor in muscle tissues selected to represent prime cuts of edible carcass meat. In contrast, increased dietary Cd resulted in significantly elevated liver and kidney Cd contents.
The nutritive value of field peas (Pisum sativum) in an oat‐based diet for laying hens
Authors: Davidson John
Published: October 2006

In an experiment with laying hens, an oat‐based diet containing one‐third ground field peas (Pisum sativum) supported egg production which was only half that on a control diet containing fishmeal. Either the addition of methionine to the diet or processing the peas by heating and flaking, increased egg production to about three‐quarters of the control output. Methionine supplementation in addition to heat processing of the peas allowed full egg production.
The transnitrosation of N‐methylaniline by a protein‐bound nitrite model system in relation to N‐nitrosamine formation in cured meats
Authors: Dennis M. John , Massey Robert C. , McWeeny David J.
Published: October 2006

The reactions of sodium nitrite, S‐nitrosocysteine hydrochloride, S‐nitrosoglutathione and a ‘protein‐bound nitrite’ model system with N‐methylaniline at pH 5.5 and 37°C have been compared. The results show that the rate of nitrosamine formation from sodium nitrite and S‐nitrosocysteine is greater than that from the model system although the latter depends upon the local concentration of nitrosothiol groups on the matrix. Transnitrosation by S‐nitrosoglutathione is considerably slower than the other reactions. The implications of the results with respect to nitrosamine formation in cured meat are discussed.
An extraction method for evaluating the seed proteins of cowpea [Vigna unguiculata (L) Walp]
Authors: Tella Ayoni F. , Ojehomon Ojeaga O.
Published: October 2006

Simple procedures were tested for the rapid extraction and estimation of albumins, globulins, glutelins and gliadins in cowpea seeds. The extraction methods were based on the differential solubilities of these fractions in buffered 2% NaCl, 0.01M NaOH and 80% aqueous ethanol. Further analysis of the fractions was carried out by polyacrylamide gel electrophoresis which showed that each fraction was a distinct entity. The total extractable protein contents of the varieties analysed varied from 19.0 to 25.7% but the relative amounts of the protein fractions changed between each other in a complementary way, such that some varieties were rich in a particular protein fraction but deficient in another. The procedure finally adopted appeared to be reasonable and convenient but it was not suitable for very dark‐coloured seeds.
Spectrophotometric determination of inorganic chloride in butter and margarine
Authors: Lau O. W. , Mok C. S.
Published: October 2006

A simple and accurate spectrophotometric method for the determination of inorganic chloride in butter and margarine has been developed. The new method is based upon the aqueous mercury(II) thiocyanate method in which thiocyanate liberated by chloride reacts with iron(III) to give an iron(III)‐thiocyanate complex with an absorption maximum at 476 nm.
The measurement of sulphur‐containing amino acids in some scottish soils
Authors: Scott Norman M. , Bick Walter , Anderson Hamish A.
Published: October 2006

Cysteic acid and methionine sulphone were measured in soil hydrolysates by ion exchange chromatography, after pretreatment of the soil with performic acid. In four mineral soils these amino acids accounted for 19‐31% of the carbon‐bonded sulphur measured by difference between total organic sulphur and total organic sulphate, but only 8% in a peat. When carbon‐bonded sulphur is measured directly by reduction with Raney‐Nickel, however, the amounts are lower, and cysteic acid and methionine sulphone together account for 80‐100% of the values for the mineral soils and 50% of that for the peat. It seems therefore that Raney‐Nickel reduces only a fraction of the carbon‐bonded sulphur consisting mainly of amino acid sulphur.
Fishmeal and oil from lantern fish (Myctophidae) with special emphasis on protein quality
Authors: Haque A. , Pettersen J. , Larsen T. , Opstvedt J.
Published: October 2006

Fishmeal made from lantern fish (family: Myctophidae; genus: Benthosema pterotum) had proximate, mineral, amino acid and fatty acid composition within the range reported for fishmeal made from conventional fish. Similarly, the pressed‐out oil had a fatty acid composition and content of unsaponifiables as reported for conventional fish oil. The content of unsaponifiables in the body fat of the fish indicated that wax esters contributed a minor part of the lipids of this species of lantern fish. Determined in chicks, the true digestibility of the amino acids varied from 92% (arginine) to 73% (hydroxyproline) which for most of the amino acids was 1‐3% units lower than that found for a high‐quality capelin fishmeal. No differences in rate of mortality, growth rate and feed consumption and utilisation were found between lantern and capelin fishmeal when they replaced increasing amounts (0 to 100%) of soya bean meal as protein supplements (72% of total protein) to cereal diets, both fishmeals reducing feed consumption and causing a significant improvement in feed utilisation compared with soya bean meal. The data indicate that lantern fish may be used for the production of fishmeal.
Susceptibility of strawberry varieties to breakdown in sulphite by endopolygalacturonase from zygomycete spoilage fungi
Authors: Harris Jane E. , Dennis Colin
Published: October 2006

Differences were observed in the texture and susceptibility to enzymic breakdown of sulphited fruit of eight strawberry varieties. Cambridge Favourite was the softest variety in sulphite and was also the most susceptible to breakdown by pectolytic enzymes of Rhizopus and Mucor spp. Endopolygalacturonases (endo‐PG) from these species were more rapidly inactivated in sulphite liquor in the presence of fruit of the variety Harvester, which consequently showed the greatest resistance to breakdown. Isoelectric focusing indicated that a single major isoenzyme from each strain of R. sexualis, R. stolonifer and M. piriformis persisted in sulphite liquor and was, therefore, responsible for breakdown, although the major form of M. piriformis was less acid‐stable than those of the Rhizopus spp. Other minor isoenzymes produced by the fungi were inactivated within 24 h of sulphiting. Each species produced its major acid‐stable endo‐PG in the three varieties tested; thus varietal differences in susceptibility to breakdown may be related to the occurrence of natural enzyme inhibitors and/or fruit structure.
Digestive enzymes of cattle
Authors: Sissons John W.
Published: October 2006

The nature of endogenous enzymes in the alimentary tract of cattle is examined and their functions in digestive processes discussed. The main digestive enzymes in cattle are salivary and pancreatic lipase, rennin, pepsin, trypsin, lactase and amylase. Maltase and isomaltase, celliobiase, trehalase, elastase and carboxypeptidase are also present. There is no evidence that cattle secrete sucrase. Most of the enzymes secreted by the gut of cattle are present at birth, although peak activities are not always reached until animals reach 2‐3 weeks of age. These activities often persist through to maturity and are generally unaffected by rumen development. The amounts of enzymes secreted are affected by several factors including the nature of the diet, the method of feeding and age. There is also appreciable variation in the secretion of individual enzymes between animals of similar age and receiving the same diet.
Estimation of hexose: Pentose ratios in solution using the phenol‐sulphuric acid method
Authors: Ford Clive W.
Published: October 2006

A procedure is described whereby the proportion of hexose: pentose in solution may be determined spectrophotometrically. The method uses the phenol‐sulphuric acid reaction and a previously unreported ultraviolet adsorption band at 312‐325 nm in the reacted solutions. The λmax of this band increases with, and is linearly related to, the ratio of hexose to total sugars in the mixture, in the range 10‐80% hexose.
Determination of soya proteins in food using an enzyme‐linked immunosorbent assay procedure
Authors: Hitchcock Christopher H. S. , Bailey Frank J. , Crimes Andrew A. , Dean David A. G. , Davis Paul J.
Published: October 2006

Classical immunoanalytical techniques are based on native antigens and their precipitation with specific antibodies: they are not very appropriate for the investigation of processed denatured mixtures. This report describes an immunoassay based on the more recent but well‐established enzyme‐linked immunosorbent assay (ELISA) procedure, which in this case is specific for soya proteins that have been solubilised in urea and then ‚renatured’︁ by removing or diluting the denaturant. Levels of soya protein 100 g−1 total protein (nominally 100%) were determined with 34 commercial soya products, using a standard reference antigen. Normal expected levels were observed with flours (average 107%) and isolates (108%), while results with concentrates (82%) and texturates (79%) were somewhat lower. Some specialised products gave little or no response, presumably because they are hydrolysed. Meat, milk, egg, wheat and field bean proteins displayed negligible interference. These preliminary results suggest that the ELISA procedure will provide a convenient general method for the qualitative characterisation and quantitative estimation of individual proteins in food products even after severe processing; it seems more attractive than many other methods reported. Immunoassay is capable of large numbers of inexpensive but sophisticated determinations of specific food components. The food analyst should regard ELISA (for the determination in situ of specific antigens in mixtures) as a powerful technique complementary to classical chromatographic and electrophoretic methods which depend on separation before determination.
Phytate and total phosphorus content of field beans (Vicia faba L.)
Authors: Griffiths D. Wynne , Thomas T. Arthur
Published: October 2006

Considerable variation was found in the phytate and total phosphorus contents of varieties, selections and genotypes of field beans (Vicia faba L.) The phytate phosphorus content of seeds taken from single plants of the variety Dacre indicated that large variations (1.93‐4.03 g kg−1), not significantly correlated with protein content, existed within an established variety. Although some variation in the ratio of phytate to total phosphorus was observed (0.40‐0.60), highly significant correlation coefficients were obtained for total and phytate phosphorus contents. The significance of the results obtained is discussed in relation to the potential for improving the nutritive value of field beans by breeding for lower phytate content.
Assessment of wheat grain texture by near infrared reflectance measurements on bühler‐milled flour
Authors: Osborne Brian G. , Douglas Stuart , Fearn Thomas
Published: October 2006

A calibration is presented between near infrared (n.i.r.) reflectance data at 1720 and 1288 nm and wheat grain kernel texture as determined by air‐jet sieving on flour Bühler‐milled from home‐grown wheat. A multiple correlation of 0.996 and a residual standard deviation of 0.140 was achieved with a calibration set of 40 samples and the result was verified by prediction of values of further samples. The calibration was valid over two successive harvests (1978 and 1979) A separate calibration was obtained using a Neotec 101 instrument using data around 2230 nm when a multiple correlation of 0.974 and residual standard deviation of 0.32 was obtained. A calibration equation and pulse point are presented.
Synergism between phospholipids and naturallyoccurring antioxidants in leaf lipids
Authors: Hudson Bertram J. F. , Mahgoub Salah E. O.
Published: October 2006

Based on oxygen absorption induction periods, the phospholipids, phosphatidylcholine and phosphatidylethanolamine, have been shown to exert a deleterious effect on the stability of lard. However, when these phospholipids are used in combination with the naturally‐occurring antioxidants, α‐tocopherol and/or quercetin, a very substantial improvement in oxidative stability can be observed. This form of synergistic interaction has been shown to account for the remarkable stability exhibited by leaf lipids.
Effects of drought on yield and on grain and malt characters in spring barley
Authors: Morgan Alan G. , Riggs Timothy J.
Published: October 2006

The effects on yield and on grain and malt characters, of drought stress applied at different stages of grain development and ripening were studied in three varieties of spring barley grown in a glasshouse. Differences between variety means were found for most of the characters studied, but only for wort filtration time was there a significant interaction between variety and irrigation treatment. Grain yield was reduced by all the treatments involving drought stress and the reduction was greatest when stress was applied at heading and maintained for at least 14 days. A similar response was found for the number of ears per plant. Number of grains per main‐shoot ear was reduced by drought stress applied at heading but not when the stress was applied from 32 days after heading until harvest. Grain size was significantly reduced by all treatments. Raw‐grain characters known to be correlated with malt extract were found to be affected by the treatments: grain nitrogen content, barley extract viscosity and the rate of sedimentation of barley flour in ethanol were all increased by drought stress, the degree of response varying with the length and timing of the period of drought. Malt extracts were reduced by drought stress whether this was applied early or late in grain development. Malting loss and germinative energy were reduced, and wort filtration time increased by late stress. α‐Amylase activity in the germinating grain was unaffected by any of the treatments.
The objective definition of eating quality in rockmelons (Cucumis melo)
Authors: Mutton Lachlan L. , Cullis Brian R. , Blakeney Anthony B.
Published: October 2006

From a set of 12 factors thought to be related to eating quality, only percentage soluble solids and penetrometer estimates of flesh firmness were useful in deriving a predictive equation. A practical grade standard might be 10% minimum solids with upper and lower limits for flesh firmness of 2.0 and 1.0 kg force.
Dietary fibre—some properties of alcohol‐insoluble solids residues from apples
Authors: Gormley Ronan
Published: October 2006

Alcohol‐insoluble solids (AIS) material prepared from apples contains about 80% dietary fibre and has therapeutic properties. The AIS content of seven apple cultivars was tested, three from a soil management experiment and four from a cultivar trial. Values for AIS content were different (P< 0.001) for cultivars in both trials, ranging from 2.89 to 4.41%. The grass soil management treatment gave higher (P< 0.05) AIS levels in the fruit than the overall herbicide treatment. In‐vitro water holding capacities (WHC) of the AIS materials were not significantly different even though values ranged from 20.8 to 25.5 g water bound g−1AIS. However, calcium binding capacities (CBC) were different for cultivars, with ranges of 3.69‐4.38 mg Ca g−1AIS material (P< 0.001) and 3.25‐4.08 mg (P< 0.05) in the two trials. Pectin content of the AIS material was different (P< 0.05) for cultivars in the soil management trial, ranging from 20.7 to 22.5%. Method of soil management had no effect on WHC, CBC or pectin content of the AIS material. Values for WHC, CBC and pectin based on 100 g fresh apple samples, as eaten, were significantly different in both trials, with grand means of 80.9 g, 14.2 mg and 0.76 g, respectively. The grass treatment gave higher CBC and pectin content in fruit than the overall herbicide treatment. These data indicate that AIS material from different apple cultivars varies in both amount and properties. The method of soil management had a lesser effect.
Potato starch, gut flora and caecal size in the chick
Authors: Coates Marie E. , Rolls Brian A.
Published: October 2006

The effects upon caecal size of feeding chicks with diets containing raw or autoclaved potato starch were tested in both germ‐free and conventional environments. Raw, but not autoclaved, potato starch produced enlarged caeca but the effect was less than that reported with rats. The gut flora had no effect on the enlargement. In one trial the chicks eating raw potato starch grew less well. The caecal concentrations of hexosamines were estimated as a measure of mucin content and were higher in germ‐free environments than in conventional chicks and higher in chicks given raw, rather than autoclaved potato starch. The possible relevance of this work to caecal size in germ‐free and conventional rodents is discussed.
The flavour components of plums: An examination of the aroma components present in the headspace above four cultivars of intact plums, marjorie's seedling, merton gem, NA 10 and victoria
Authors: Ismail Hanaa M. M. , Williams Anthony A. , Tucknott Owen G.
Published: October 2006

Qualitative and quantitative examination of the aromas above four cultivars of intact plums, using gas chromatography and gas chromatography‐mass spectrometry, gave information on 33 components of which linalool, benzaldehyde, methyl cinnamate and y‐decalactone were present in regions of the chromatogram associated with plum‐like aromas. Comparison of the analytical data with the scoring of plum‐like character by sensory means showed that the percentage concentration of these compounds only related approximately to the sensory scores, whereas the percentage of hexanol, the major component present in the extracts, was inversely related.
Detection and estimation of collagen
Authors: Etherington David J. , Sims Trevor J.
Published: October 2006

Collagen exists in at least five genetically distinct forms and the relative abundance of these is determined by the type and age of the tissue. Methods are presented for the detection and estimation of these collagens based on appropriate chemical, physical, histochemical and immunological techniques. The specific difficulties in providing accurate quantitative data for collagen in meat and meat products'are discussed.
Selected functional properties of sesame (Sesamum indicum L.) flour and two protein isolates
Authors: Dench Jane E. , Rivas R. Nilo , Caygill John C.
Published: October 2006

Functional properties of sesame flour and protein isolates have been compared with those of some commercial soya products. The sesame products showed better fat absorption, poorer water absorption and overall lower bulk densities than soya products. Emulsifying activities and stabilities were generally lower than soya products. Destabilisation of the emulsion in the presence of NaCl was noted. Sesame products showed better foam expansion, and comparable foam stability and strength to corresponding soya products. Addition of sugar to sesame whips reduced foam expansion and increased foam stability. Acid, neutral and alkaline sesame whips showed distinct whipping properties depending on the product used. Sesame whips resembling those of egg‐white could be obtained. The sesame isolate prepared by alkaline extraction was superior to that prepared by salt extraction in terms of their pH‐solubility profiles.
Nitrogen extractability of sesame (Sesamum indicum L.) seed and the preparation of two protein isolates
Authors: Rivas R. Nilo , Dench Jane E. , Caygill John C.
Published: October 2006

Nitrogen extractability from sesame flour in water is greatest using a flour: solvent ratio of 1:40 and an extraction time of 15 min. At pH 4.0‐6.5, <10% nitrogen is extracted, whilst >90% is extracted at pH 11.0. In the presence of NaCl (0.5‐1.0M) nitrogen extractability is greatest at pH values > pH 4.0. The two sesame protein isolates produced were bland‐tasting, light‐coloured and contained approximately 95% protein. The alkali isolate (extracted in water at pH 10.0 and precipitated at pH 4.0) was readily solubilised and showed a good protein recovery (60%). The salt isolate (extracted in 1M NaCl at pH 6.0 and precipitated at pH 4.0) was less soluble and showed a lower protein recovery (50%). The sesame products were extracted sequentially using various solvents. Sesame flour proteins were mainly salt‐soluble (67%), alkali isolate proteins mainly water‐soluble (41%) and alkali‐soluble (41%), and salt isolate proteins mainly alkali‐soluble (35%). The amino acid composition of the sesame products is described. Oil‐expelled cake showed poor nitrogen extractability (53% at pH 11.0 in water) and was, therefore, a poor source for protein isolate production.
Protein enrichment of cassava root meal by trichoderma harzianum for animal feed
Authors: Muindi Pancras J. , Hanssen Jon F.
Published: October 2006

A fermentation procedure to increase the protein content of cassava root meal (CRM) with Trichoderma harzianum is described. The organism was grown in a 4% CRM medium with inorganic nitrogen. The fungal biomass plus the rest of CRM were collected by filtration at the end of fermentation. Satisfactory results were obtained at 23 °C (pH 4.0‐4.2) and a fermentation time of 60 h. The CRM/biomass contained about 38% crude protein (CP) on a dry matter basis. This should be compared with 2.4% CP in the untreated CRM. The sum of amino acids in the product corresponded to about 60% of the CP value. The estimated efficiency of conversion of the CRM into CRM/biomass was found to be about 30%. A substantial improvement in the protein content and quality of CRM can be made through submerged cultivation of T. harzianum on CRM.
Preventing phosphorus losses during perchloric acid digestion of sodium bicarbonate soil extracts
Authors: Brookes Philip C. , Powlson David S.
Published: October 2006

Between 10 and 40% of P was lost during perchloric acid digestion of NaHCO3 soil extracts for measurement of organic P. This observation was confirmed by 32P tracer experiments. Addition of MgCl2 prevented P loss, reduced variability of replicate determinations and ensured virtually 100% recovery of P added to NaHCO3 solution and NaHCO3 soil extracts before digestion. Losses were due both to P volatilisation and conversion of P to forms other than ortho‐P in the digestion mixture.
The reaction of an azo food dye with hydrogen sulphite ions
Authors: Wedzicha Bronislaw L. , Rumbelow Stephen J.
Published: October 2006

The kinetics of the reaction between carmoisine and hydrogen sulphite ions are reported in the pH range 4‐5.3. The stoichiometry is 1:1 and the major sulphurcontaining product is sulphate ion. A mechanism consistent with experimental data is proposed.
Effect of canning and storage on carotenoids (vitamin A activity) and vitamin C in Spanish and Turkish oranges
Authors: Valadon L. R. Guy , Mummery Rosemary S.
Published: October 2006

Canning caused a small reduction in the vitamin C content of orange purée of both Spanish and Turkish varieties; subsequent storage for 24 months at 10°C caused complete loss of vitamin C. Carotenoids, however, were retained to a limited extent after storage and similar amounts were present at both room temperature and at 10°C. Most of the vitamin C in the flavedo was retained after 24 months' storage at ‐ 20°C but there was a considerable fall when the frozen material was thawed and stored at room temperature for 4 days. Thirteen carotenoids were present in both varieties of purée, with three additional ones in the Spanish variety and one additional one in the Turkish variety. Despite the heating in acid conditions involved in the canning process, only two of the pigments, violaxanthin and flavoxanthin, isomerised from the all‐trans to cis‐trans isomers.
Salicylic acid in fresh and canned fruit and vegetables
Authors: Robertson Gordon L. , Kermode William J.
Published: October 2006

The salicylic acid concentration in a range of fresh and canned fruit and vegetables was determined using a sensitive spectrofluorimetric technique. Concentrations in fresh fruit ranged from 0.02 mg kg‐1 in kiwifruit to 0.10 mg kg‐1 in New Zealand grapefruit, and in fresh vegetables from 0.01 mg kg‐1 in cabbage to 0.10 mg kg‐1 in whole kernel sweet corn. In canned products, salicylic acid levels ranged from 0.01 mg kg‐1 in pears to 0.82 mg kg‐1 in cream‐style sweet corn. Canned sweet corn and some tomato products had higher levels than the corresponding fresh vegetables. Evidence was obtained to suggest that, in the case of whole kernel sweet corn, the application of heat increased the concentration of free salicylic acid.
The extraction of nitrogen from the west African locust‐bean seed (Parkia filicoidea Welw.)
Authors: Balogun Olufemi O. , Odutuga Adewale A.
Published: October 2006

Techniques for maximising the extraction of nitrogen from the West African locustbean seed (Parkia filicoidea Welw.) have been investigated. Maximum extraction (93 %) of nitrogen was obtained using a meal:solvent ratio of 2% with 0.05M NaOH. However, from the economic viewpoint a meal:solvent ratio of 1% using 0.01M NaOH would be cheaper. This ratio extracted 82% of the seed nitrogen. Other solvents such as sodium chloride solution and calcium hydroxide were not as efficient.
Fermentation of tea in aqueous suspension. Influence of tea peroxidase
Authors: Dix Margaret A. , Fairley Charles J. , Millin David J. , Swaine Derwent
Published: October 2006

The natural peroxidase and catalase of tea leaf were shown to be active under the conditions employed for the fermentation of minced tea leaf in aqueous suspension. Fermentations carried out under nitrogen with ethyl hydrogen peroxide, which is not decomposed by catalase, yielded predominantly thearubigins, a high proportion of which were polymeric in nature. Fermentations using an excess of hydrogen peroxide gave similar results. Fermentations under conditions of controlled dissolved oxygen using both air and hydrogen peroxide resulted in a pigment distribution intermediate between those observed using air alone and using ethyl hydroperoxide under nitrogen. Adjustment of the amount of hydrogen peroxide used to around 120 μmol g−1 leaf resulted in a pigment distribution closely similar to that of a good quality black tea. A mixture of theaflavins was stable in the presence of air and tea polyphenoloxidase but decomposed rapidly to yield polymeric materials under the action of hydrogen peroxide and peroxidase derived from tea or horseradish. Kinetic measurements suggest that tea flavanols are generally poorer substrates for peroxidase than for catechol oxidase. However, the level of peroxidase is high and, furthermore, in view of the respective pH optima of the two enzymes, its action would be favoured as the pH falls during fermentation. It is postulated that the nature and distribution of the pigments formed during the fermentation of tea is governed in part by the relative actions of catechol oxidase and peroxidase. These actions are, in turn, influenced by the availability of oxygen and the action of catalase.
Short‐term toxicity study of irradiated cocoa beans in rats
Authors: Takyi Etor E. K. , Ofori‐Mensa Nana
Published: October 2006

Groups of rats (30 males and 30 females) were fed stock diet and diets containing 350 g kg−1 of cocoa beans (non‐irradiated or irradiated) for 18 weeks and observed for food consumption, haematological variations, changes in growth pattern and gross pathology. Even though there was no significant difference among the groups in haematological or gross pathological examinations, consistently less food was consumed by rats fed on diets containing either non‐irradiated or irradiated cocoa beans. Furthermore, weight gain and terminal body weights of rats fed on cocoa‐containing diets were less than those fed on the stock diet. Such differences, may at least in part, be due to alkaloids in the cocoa‐containing diets and not as a result of irradiation of the beans.
Changes in the carotenoids and sterol fractions during the prolonged storage of wheat flour
Authors: Farrington William H. H. , Warwick Michael J. , Shearer George
Published: October 2006

Changes in the carotenoid and sterol fractions of three wheat flours have been studied during storage. Total carotenoid decreased throughout the storage period; the relative rates of loss in each flour were the same as the relative rates of oxidation of polyenoic acids previously found to occur in these flours. Hexane‐extractable total sterol content remained unchanged during storage. Esterification of free sterol was demonstrated and esterification of free lutein was also indicated.
Creatine as an indicator of net muscle proteins
Authors: Dvořák Zdeněk
Published: October 2006

Creatine and creatinine levels in different cuts of pork, beef, veal and lamb have been estimated and expressed in relation to the content of total proteins (N × 6.25) and net muscle proteins (N × 6.25 minus hydroxyproline × 8). The relationship between creatine and total proteins was not linear. Creatine values were linear with those for net muscle protein, giving a mean value of 23 mg creatine g−1 net muscle protein in these meats. Creatinine values averaged 1 mg g−1 net muscle protein. The results are discussed in connection with using creatine as an index of meat quality and with using urinary creatinine as an index of muscle mass of the animal.
The chemical components and decomposition of wheat straw leaves, internodes and nodes
Authors: Harper Stephen H. T. , Lynch James M.
Published: October 2006

Chemical analysis of wheat straw reveals that internodes have larger cellulose but smaller hot‐water‐soluble fraction contents than either leaves or nodes. Lignin and hemicellulose contents are similar. The leaves and nodes of wheat straw lose weight more rapidly than the internodes during the early stages of aerobic decomposition. This is at least in part a consequence of the more rapid losses of the polysaccharides in leaves and the hot‐water‐soluble materials in nodes. Internodes also provide a poorer substrate than leaves and nodes for the anaerobes which produce acetic acid.
Isolation of the egg weight depressing factor in fababeans (Vicia faba L. var. minor)
Authors: Olaboro Gershon , Marquardt Ronald R. , Campbell Lloyd D.
Published: October 2006

Two experiments were conducted to study the egg weight depressing effect of an ethanol‐water extract of autoclaved fababean protein concentrate. Acetone fractionation of the extract produced four fractions, one of which (fraction H), significantly depressed egg weight. Further fractionation of fraction H produced two fractions; a highly water‐soluble supernatant fraction and a fraction with low water solubility which was harvested as a white precipitate. Both the supernatant and the white precipitate, when added to diets in proportion to their relative yields, caused similar depressions in egg weight. The observation that there was a direct relationship between amounts of vicine‐reactive material in the different fractions and the magnitude of egg weight depression indicates that the principal egg weight depressing factor in fababeans is vicine and/or convincine.
Pectin changes in the pre‐cooking step of dehydrated mashed potato production
Authors: Moledina Kabir H. , Haydar Muhammad , Ooraikul Buncha , Hadziyev Dimitri
Published: October 2006

Some in‐vivo and in‐vitro characteristics of pectin methylesterase (PME) from cell wall and whole potato tuber were determined and its role was elucidated in the pre‐cooking and cooling steps of commercial dehydrated mashed potato production. The isolated cell walls contained 16.3% anhydrogalacturonic acid with a degree of esterification (DE) of 56, and 25% of tuber total PME. Cell wall pre‐cooking in model systems resulted in a DE of 53.2. Native cell wall pectin solubilisation was much less than that of H‐cell walls devoid of metal cations. Calcium but not Mg, supplied as Ca(Mg)‐starches, retarded pectin solubilisation, while Ca‐uptake by retained pectin was high when cooling followed pre‐cooking. Texture measurements of potato slices pre‐cooked, cooled and cooked suggested a firming effect which could be attributed to Ca‐release from gelatinised starch during pre‐cooking, and stabilisation of Cabridges with free COO− groups of cell wall pectin duringcooling. The role ascribed to PME in causing firming is de‐emphasised.
Essential oils from two varieties of Ocimum basilicum L. Grown in Israel
Authors: Fleisher Alexander
Published: October 2006

The yield, quality and composition of essential oils from sweet basil plants grown in Israel have been investigated. It has been found that at the same phenological stage the content of essential oil in the plant increases towards the autumn. The oil content increases as the plant develops and reaches its maximum in the full bloom stage. The presence of two chemotypes (A and B) of Ocimum basilicum L. plants was established. The variation in composition of the oil during the period of bloom was investigated for both chemotypes. Up to 25 % of the total of basil oil of type A and 50 % of type B oil were extracted from distillation water by the poroplast column technique. This secondary oil, of pleasant odour, contains mainly the most polar compounds, such as eugenol, linalool and cineol.
The effects of some additives on the microflora of silage
Authors: Menna Margaret E. Di , Parle Jack N. , Lancaster Robert J.
Published: October 2006

The microflora of experimental batches of grass silage treated with formaldehyde, with formaldehyde plus formic acid, or with sodium benzoate and held at a constant temperature of 20°C was examined during fermentation and after exposure to air. The formaldehyde treatments inhibited the development of lactobacilli during fermentation but their biocidal effect did not persist and on exposure to air microbial numbers increased and the pH of the silages rose at a similar rate to that in untreated silage. Treatment with sodium benzoate had little effect on fermentation but its biostatic, particularly fungistatic, activity persisted through 17 days of exposure to air during which the pH did not rise and fungal numbers remained low. The yeast flora of all treatments was predominantly of fermenting species similar to that found in stack silages but the mould flora, of Geotrichum candidum, Mucor spp. and Penicillium spp., was dissimilar and could be related to the lack of heating in the experimental silages.
Polymorphism of rapeseed oil with a low content of erucic acid and possibilities to stabilise the β′‐crystal form in fats
Authors: Hernqvist Lars , Larsson Kåre , Herslöf Bengt , Podlaha Oldrich
Published: October 2006

The polymorphism of hydrogenated rapeseed oil with a low content of erucic acid was investigated by X‐ray diffraction. The triglyceride composition in the hydrogenated oil was determined by a combination of gas chromatography and high‐performance liquid chromatography. A characteristic feature of this oil is its rapid transition to the β‐form. Possibilities of influencing the β′→ β transition are discussed. The addition of diglycerides appears to provide a means for delaying the β′rarr; β transition. Thus, 1,2‐diglycerides show a strong stabilising effect on the β′ triglyceride crystals form, which is considered to be of technical interest.
The evolution of champagne volatiles during ageing
Authors: Loyaux Denis , Roger Sylviane , Adda Jacques
Published: October 2006

The change in aroma composition during champagne ageing on yeast has been studied by gas chromatography and coupled gas chromatography‐mass spectrometry of the volatiles trapped on Porapak Q. Analyses were made on samples kept on yeasts for 2 months and 1, 2, 3, 4, 5, 6, 7 and 16 years, respectively. A rapid increase in the level of volatiles was noted in the first period. As ageing proceeded a slow decrease of nero‐lidol, isoamyl butyrate and hexyl acetate level was observed while vitispirane and benzaldehyde concentrations increased. After a 16 year period, benzaldehyde concentration increased to a level of 4 mg litre−1.
Carbohydrate composition of developing grains of the high‐lysine barley mutant (notch‐2) and its parent (NP 113)
Authors: Batra Vijay I. P. , Bansal Hukam C. , Mehta Shanti L.
Published: October 2006

Barley variety NP 113 had higher accumulations of dry matter (DM) and starch than its high‐lysine mutant, Notch‐2, during grain development. Protein, amylose and amylopectin content per grain were lower in Notch‐2 than NP 113. Reducing sugars, free glucose, total fructose and non‐reducing sugars were 1.57–3.15‐fold in Notch‐2 grain as compared with NP 113 grain. DM, protein, starch, amylose and amylopectin per grain increased during grain development. Soluble sugar contents per grain were maximum at 24 days after anthesis. Lower DM accumulation in the Notch‐2 mutant as compared with its parent, NP 113, is due to lower starch deposition. Further, the limitation of starch synthesis in the Notch‐2 mutant is not due to any limitation in the supply of soluble sugar precursors.
Biochemical changes in developing wheat grains. Changes in nitrogen fractions, amino acids and nutritional quality
Authors: Kapoor Amin C. , Heiner Robert E.
Published: October 2006

Two spring wheat cultivars (Triticum aestivum L. em Thell.), one tall (Chris) and the other semi‐dwarf (Era), with different yields and grain protein potentials, were grown in controlled environment chambers to compare the nitrogen fractions, amino acids and nutritional quality in developing grains at 12, 22, 29 and 36 days after heading. The proportions of gliadin I, gliadin II and glutenin II increased and those of albumin and globulin decreased as the wheat cultivars matured. The amount of lysine, methionine, threonine, valine, tyrosine, alanine, aspartic acid and glycine was lower and that of glutamic acid and proline was higher with grain development in both cultivars. At 12 days after heading Era had a higher content of amino acids (16 g−1 N) than Chris. Isoleucine was the first limiting amino acid in Era and Chris at the first collection period whereas at later stages lysine was the limiting amino acid in both cultivars. Chemical score, essential amino acid index, requirement index and calculated biological value all decreased as the grain matured and, except for the 12‐days collection period, the data were almost similar for both the cultivars.
Nutritional and toxicological evaluation of ‘black tip’ rice
Authors: Bhat Ramesh V. , Deosthale Yeshwant G. , Roy Dwijendra N. , Vijayaraghavan Malini , Tulpule Purushotham G.
Published: October 2006

A popular newly introduced rice variety Phalguna (RP 6–17) was found to be susceptible to the development of black colour at the tip of the grains. On parboiling the paddy, the degree of discoloration intensified and occasionally even the entire kernels were found to be discoloured. In the affected grains the breakages during milling were considerably higher than the unaffected grains. There was not much difference between the nutrient composition of the black tip and normal grains. However, contents of iron and free sugar were found to be higher in black tip grains than that in normal grains. A positive correlation between extent of discoloration of the grains and the glucosamine content was observed suggesting that this criterion could be used as an index of fungal contamination. Species of Alternaria and Curvularia were found to be more predominant in black tip raw rice than normal raw rice. Acute toxicity studies in chicks and ducklings and short‐term toxicity studies in rats did not indicate ill effects.
The quantitative analysis of indole glucosinolates by gas chromatography — the importance of the derivatisation conditions
Authors: Heaney Robert K. , Fenwick G. Roger
Published: October 2006

The effect of derivatisation conditions on the quantitative analysis of indole glucosinolates as the desulphated trimethylsilyl derivatives using gas chromatography is examined. Structures for the trimethylsilyl derivatives of glucobrassicin and neoglucobrassicin are suggested from an analysis of their ammonia chemical ionisation mass spectra. Caution is urged in the analysis of these compounds without prior optimisation of the conditions of derivatisation.
Effects of season, cultivation and nitrogen fertiliser on the size of the soil microbial biomass
Authors: Lynch James M. , Panting Lynda M.
Published: October 2006

In arable soil, the biomass in the surface 5 cm of soil, as measured by the fumigation/respiration technique, increased when roots grew, reached a maximum around the time of maximum root production and thereafter declined. Rotovation of the soil in autumn resulted in a smaller biomass than in undisturbed soil, but only in the spring. Straw on the soil surface seemed not to affect the biomass, but it may have caused a transient increase in early autumn. Application of nitrogen fertiliser increased the biomass in soil after direct‐drilling cereals but not after ploughing.
Formation of cyanide as a product of decomposition of cyanogenic glucosides in the treatment of elderberry fruit (Sambucus nigra)
Authors: Pogorzelski Eugeniusz
Published: October 2006

Distribution of cyanogenic glucosides contained in elderberry fruit was investigated in the course of technological operations usually utilised for obtaining musts. The degree of glucoside hydrolysis was estimated by the amount of liberated hydrogen cyanide. After fermentation on skins the must contained 2.08 mg litre−1 of hydrogen cyanide. Hydrogen cyanide in the must from depectinised fruit pulp was at a level of 2.31 mg litre−1. After heat treatment the must contained 1.07 mg litre−1 of hydrogen cyanide.