bluuebunny/crossref_metadata_2025 huggingface dataset:
Flavour quality of tomatoes
Authors: Dirinck Patrick , Schreyen Luc , Van Wassenhove Fredy , Schamp Niceas
Published: November 2006

Tomato volatiles present in essential oils obtained by steam distillation–continuous extraction and by head‐space condensation were identified and evaluated organoleptically. Flavour quality of different samples of fresh tomatoes, evaluated by a panel, could be related to the occurrence and concentration of n‐hexanal, trans‐2‐hexenal, cis‐3‐hexen‐1‐ol, 2‐isobutylthiazole and some unidentified compounds in the head space condensation essential oil.
Sulphur–nitrogen interaction effects on the yield and composition of the protein‐N, non‐protein‐N and soluble carbohydrates in perennial ryegrass
Authors: Bolton John , Nowakowski Tadeusz Z. , Lazarus William
Published: November 2006

In a controlled‐environment pot experiment sulphur fertilisers increased the yields of ryegrass when large dressings of nitrogen were also given. Yield responses to sulphur occurred when the dry matter contained less than 0.20% S. At the third cut, sulphur deficiency decreased concentrations of reducing sugars but had little effect on sucrose and fructosan in the grass dry matter. Only 44% of the nitrogen in the most sulphur‐deficient grass was protein‐N as compared to over 80% in non‐deficient grass. The non‐protein‐N accumulated predominantly as amides especially asparagine. The amino acid composition of the insoluble protein, including the proportions of cystine and methionine, was unaffected by acute sulphur or nitrogen deficiencies.
Manipulation of fermentation in the rumen
Authors: Harrison David G. , Beever David E. , Thomson David J. , Osbourn Dennis F.
Published: November 2006

Artificial saliva (4 litres/day) was infused into the rumen of sheep fed a semi‐purified diet at hourly intervals. Dilution rate and the efficiency of synthesis of microbial protein in vivo were increased. The pattern of rumen fermentation was altered; the molar proportion of propionic acid decreased (32–20%) and acetic acid increased (58–66%) with infusion, and there was an increased flow of total amino acids into the duodenum.
Chemical composition of microbial matter in the rumen
Authors: Czerkawski Julian W.
Published: November 2006

Microbial fractions, comprising protozoa, large and small bacteria and whole particulate matter, have been isolated from rumen contents of sheep given a mainly concentrate diet, a mixture of hay and concentrate, and hay only. Samples of rumen contents were taken before and 2 h after feeding. The main components determined were: protein, lipid, nucleic acids, carbohydrate and ash. The amount of cell wall was estimated in terms of known cell wall constituents (diaminopimelic acid (DAP) and glucosamine). The concentration of some of the constituents varied with diet and with respect to the time of feeding. Many of the differences disappeared when the results were expressed on a polysaccharide‐free basis. The amino acid composition of large and small bacteria was virtually the same. The amino acid composition of protozoa was similar except for the proportions of glutamic acid and lysine which were greater in protozoa, and alanine, glycine and DAP, the proportions of which were greater in bacteria. There were higher proportions of protein in large bacteria and protozoa than in small bacteria. Small bacteria contained more lipid, ash and DNA, and less RNA than the other two fractions. The polysaccharide content of protozoa and large bacteria increased from about 8% before feeding to about 30% after feeding, while the polysaccharide content of small bacteria increased only slightly after feeding.
Estimation of S‐methylcysteine sulphoxide (kale anaemia factor) and its distribution among brassica forage and root crops
Authors: Whittle Peter J. , Smith Ronald H. , McIntosh Alexander
Published: November 2006

S‐methylcysteine sulphoxide (SMCO), kale anaemia factor, was quantitatively extracted from a variety of brassica crops by repeated maceration in water. It was separated from other components of the deproteinised extract by electrophoresis on silica gel impregnated glass‐fibre sheet; and after visualising with ninhydrin/cadmium acetate reagent, the SMCO spots were quantitated by reflectance‐mode densitometry. Values for SMCO contents of plants thus obtained agreed well with those obtained by ion‐exchange chromatography. The method is useful for rapid screening of a large number of plants, as well as for making fewer more accurate determinations. Ten varieties of kale and five of forage rape were grown on experimental plots and harvested at intervals between August and January. The SMCO content of the plants increased as they matured and secondary growth began. The flowers of kale contained twice as much SMCO per unit weight as the whole plant and were very toxic to cattle. Varietal differences in SMCO content were found in plants analysed before the onset of secondary growth, Maris Kestrel and Cauletta showing lower values than other varieties. Substantial amounts of SMCO were found in swedes, both in the “roots” and the “tops”, each structure being toxic to cattle. Other brassicas examined included Chinese cabbages, turnips, fodder radish and a Raphanobrassica.
The influence of an extract of orange peel on the growth and ascorbic acid metabolism of young guinea‐pigs
Authors: Wilson H. Kerr , Price‐Jones Chris , Hughes R. Elwyn
Published: November 2006

Young male guinea‐pigs receiving a maintenance dose of ascorbic acid (vitamin C) (0.1 mg/100 g body weight daily) received a daily supplement of a flavonoid‐rich extract of orange peel (5 mg/100 g body weight). The extract significantly increased the ascorbic acid concentration on the adrenals, spleen and leucocytes but not in the liver and brain. Hesperidin had a similar effect. The possible mechanisms of these changes are discussed. The orange extract and the hesperidin both produced a marked increase in the body weight of the guinea‐pigs; this effect was absent in ascorbic acid sufficient guinea‐pigs. The extract did not influence the survival time of the scorbutic guinea‐pigs. These indications of a partial vitamin C activity on the part of the flavonoids suggest that ascorbic acid is a multifunctional vitamin with its growth‐promoting function separate from (and presumably subordinate to) the prevention of scurvy.
Conditions affecting production of a protein isolate from lupin seed kernels
Authors: Ruiz Leonard P. , Hove Edwin L.
Published: November 2006

Conditions were investigated to determine the optimum processing parameters for preparation of a protein isolate from the ground, dehulled lupin seeds of Lupinus angustifolius. The extraction variables were: particle size (16–100 mesh); pH (2–11); extraction medium; solvent to lupin ratio (10:1 to 40:1); temperature (20–60oC) and time (15–60 min). The isoelectric point of the lupin protein was found to be pH 4.5 with a protein solubility of greater than 90% above pH 8.0. Using 60–100 mesh ground lupin and extracting at pH 8.5 for 30 min, a protein isolate was obtained on acidification to pH 4.8 which was 89.4% protein compared to 34.0% protein for the original dehulled lupin. This protein isolate represented 19.8% of the starting material and 52% of the starting nitrogen. Similar results were also obtained when hexane defatted lupin was used. In this case the protein isolate had a protein content of 92.5%. The yield of protein isolate could be increased to 25.7% of the starting material if the extraction was repeated. The protein efficiency ratio for the protein isolate was 2.90 when supplemented with methionine.
Effects of seed rate, nitrogen level and leaf age on the yield of extracted protein from five different crops in West Bengal
Authors: Matai Shyam , Bagchi Dipak , Chanda Sunanda
Published: November 2006

The yield of leaf protein from five different crops grown at different seed rates and nitrogen levels was studied. Bajra (Pennisetum typhoideum Rich.) and mustard (Brassica nigra Koch) gave large protein yields. Harvesting just before the initiation of flowering produced the highest yield except with hybrid Napier (P. typhoideum x P. purpureum) and turnip (Brassica rapa L.). With the latter, maximum yield was obtained 45–52 days after sowing, and with the former 62 days. Seed rates of 120–150 kg/ha (4–5 times normal) were used with bajra and ragi (Eleusine coracana Gaertn), 30 kg/ha with mustard and 8 kg/ha with turnip. The yield of extracted protein was not increased by giving mustard more than 60, ragi more than 160 and bajra more than 240 kg N/ha. The N level for maximum response was not reached with turnip and hybrid Napier. More of the leaf protein was extracted from mustard and turnip than from the other species; mustard and turnip also gave the largest yields of protein (7.6 and 5.7 kg/ha/day respectively).
Changes in biochemical components during the germination of spores of Penicillium roqueforti
Authors: Fan Tsai Y. , Kinsella John E.
Published: November 2006

Germination of spores of Penicillium roqueforti consisted of three stages, i.e. swelling, germ‐tube emergence and hyphal elongation which occurred at 4, 12 and 16 h respectively after initiation of incubation of resting spores in the germination medium. The swelling phase represents the period during which the germinating spore assembled required synthetic enzymes though there was only a small increase in dry weight (2 mg h−1 per 109 spores). Nuclear division occurred since DNA multiplied rapidly during spore swelling. The percentages of RNA and proteins reached their maxima at the end of this period. The unsaturated fatty acids, e.g. linoleic and linolenic acids, were synthesised. Germ‐tube emergence represented a transition phase during which growth was moderate (at a rate of 9 mg h−1 per 109 spores) as compared to hyphal elongation phase (34 mg h−1 per 109 spores). The percentage of RNA, proteins and carbohydrates decreased. The percentage of unsaturated fatty acids was highest at the middle of this period and then declined. The hyphal elongation phase represented a period of rapid growth. The relative contents of proteins and DNA remained constant while the percentage of carbohydrates and saturated fatty acids increased, reflecting the proliferation of cellular and membrane materials.
Autolytic methods for the reduction of the purine content of baker's yeast, a form of single‐cell protein
Authors: Trevelyan William E.
Published: November 2006

When a suspension of baker's yeast was incubated at 50°C, the cells became permeable to H+, a process completed in about 4 h. Cellular constituents of low molecular weight then diffused into the medium, but only after a long lag period were cell nucleic acids and proteins degraded by intracellular enzymes. The lag period was shorter at higher temperatures, when RNase and proteinases suffered some thermal denaturation. It was abolished if, before autolysis at 50°C, yeast was plasmolysed by ethyl acetate, or heated to 70°C for 1 min, treatments which, it is thought, disorganised the membrane of the yeast cell vacuole, within which the enzymes are located. Heat treatment, when effective, was sufficiently severe to disorganise the yeast cell plasma‐lemma, with the consequence that a single adjustment of pH immediately following heat treatment served to maintain a constant pH, without addition of buffer, during the subsequent incubation at 50°C. Autolysis was not found to be an entirely suitable procedure for the reduction of the nucleic acid content of baker's yeast, because of the concomitant and severe loss of protein.
An automated colorimetric method for determining oxalic acid in plant material
Authors: Cooke David T. , Sansum Linda L.
Published: November 2006

A simple, automated colorimetric method for determining oxalic acid in plant material is based on the quantitative reduction in colour of a zirconium/3,4‐dihydroxyazobenzene‐2′‐carboxylic acid complex by microgram quantities of oxalic acid. It is suitable for use over a wide range of oxalic acid concentrations. Interference from phosphate, sulphate, citric acid and malic acid was encountered but by appropriate sample dilution this problem was resolved.
Freeze–thaw gelation of hen's egg yolk low density lipoprotein
Authors: Kamat Virendra , Graham Gillian , Barratt Martin , Stubbs Morris
Published: November 2006

The freeze–thaw gelation of hen's egg yolk low density lipoprotein (l.d.l.) has been examined by viscometry, agarose gel filtration, electron spin resonance spectroscopy, electron microscopy and differential scanning calorimetry. The data indicate that the core lipids, the hydrocarbon chains of interfacial lipids of l.d.l. and the sulphydryl, imino, amino and tyrosine groups in the side chains of l.d.l. peptides are not directly involved in the gelation mechanisms. The gelation is caused by non‐specific aggregation due to cross‐linking of peptides and/or phospholipid polar head groups of adjacent l.d.l. particles. During freezing, interparticle contacts are formed and strengthened as transformation of solvent water into ice increases the concentration of the particles. Salt and sugar additives inhibit large increases in concentrations of l.d.l. during freezing and prevent gelation by helping to increase solvation of interfacial regions of the l.d.l. particles. Agents that induce large viscosity increases in the l.d.l. sols before freezing may act by producing a local conformational change in l.d.l. protein and/or disrupting lipid–protein bonds.
Effects of fertilizer on the seedling emergence of vegetable crops
Authors: Hegarty Terence W.
Published: November 2006

In a field experiment on fertilizers applied at 0, 100 and 200 units/acre to the seedbed only nitrogen fertilizer caused a reduction in seedling emergence, though nitrogen, phosphate and potassium fertilizers did cause delays in crop emergence (calabrese, carrot, onion and red beet). In a pot experiment investigating the effects of the equivalent of 0, 125, 250, 375 and 500 kg/ha of nitrogen incorporated to a depth of 100 nm in soil, high fertilizer levels and low soil moisture resulted in reduced seedling emergence. Carrot was most sensitive and calabrese least sensitive to moisture stress. The rate of seedling emergence in carrot and onion was linearly related to water potential. Where absolute levels of seedling establishment and uniformity of crop establishment are considered to be important in vegetable growing it is recommended that inorganic nitrogen fertilizer be omitted from broadcast seedbed fertilizer dressings.
Determination of volatile fatty acids C1–C6, and lactic acid in silage juice
Authors: Jones Dilys W. , Kay James J.
Published: November 2006

A method for the determination of volatile fatty acids, C1–C6, and lactic acid in silage juice is described. The procedure is simple and capable of application to large numbers of samples. It involves separation of the free acids by ion exchange, formation of their benzyl esters by the addition of benzyl bromide to a solution of the tetrabutylammonium salts in acetone and ultimate determination by gas liquid chromatography.
Improved separation of the major water‐soluble proteins of soya meal by a single‐step chromatographic procedure
Authors: Fisher Christopher E. , Leach Ian B. , Wilding Peter
Published: November 2006

A method is described in which the major water‐soluble proteins of soya meal—the storage globulins, glycinin and γ‐conglycinin, and the anti‐nutritional factors, Kunitz trypsin inhibitor and soya bean haemagglutinin—are resolved from one another in a single‐step chromatographic procedure. The method can be used as a basis for the preparation of these components, and also as an analytical tool for examining soya protein‐containing materials.
Rapid separation and analysis of Nϵ‐(γ‐glutamyl)‐L‐lysine‐and Nϵ‐(β‐aspartyl)‐L‐lysine in protein digests
Authors: Otterburn Michael S. , Sinclair William J.
Published: November 2006

The separation and resolution of the isopeptides Nϵ(γ‐glutamyl)‐L‐lysine and Nϵ(β‐aspartyl)‐L‐lysine formed in heated proteins has been successfully achieved. The method demands a well‐characterised ion‐exchange column and the use of pH 3.40 lithium citrate buffer (0.2 N Li+). Due to the variations in particle size and cross‐linkages in the ion‐exchange resin a computer‐assisted buffer gradient system has been developed. This system effects resolution of both isopeptides in 7 h. The use of leucyl‐glycine as an internal standard facilitates quantitative estimation of the isopeptides.
The effect of marinading on beef
Authors: Wenham Lynette M. , Locker Ronald H.
Published: November 2006

Beef sternomandibularis muscle was tenderised by marinading in 1.5% acetic acid. The effect was marked whatever the cooking temperature, but greatest with mild or severe cooking (60 or 100°C). Addition of 12% sucrose further increased tenderness. Juiciness was not improved, with or without sucrose. Longissimus dorsi steaks when marinaded and grilled showed only a small increase in tenderness. Lengthy soaking of a thick steak is necessary to achieve full penetration of the marinade. Marinading appears to be particularly effective in tenderising muscles containing a large amount of connective tissue, but the benefit is marginal in top quality cuts.
Analysis of “gluten‐free” foods for trace amounts of gluten using gel electrophoresis
Authors: McCausland Jeanette , Wrigley Colin W.
Published: November 2006

The presence of gluten in speciality foods for individuals with coeliac condition can be estimated quantitatively in the range of 0.1–1.0 mg gluten nitrogen per gram sample by a specific extraction procedure followed by electrophoresis and densitometry. After preliminary lipid removal by extraction with petroleum spirit (containing 1% formic acid), gliadin is extracted with chloroform–methanol (equal volume mixture). The extract is evaporated to dryness and the residue, suspended in acidic urea solution, is used for starch gel electrophoresis at pH 3.1. The amount of β, γ and ω gliadins is estimated by densitometry. The procedure detects (and distinguishes) gluten‐type protein from wheat, rye, triticale, barley and oats. Proteins from maize, soy, egg and milk do not interfere. The method is primarily designed for testing unbaked foods, and is less satisfactory with baked goods.
The influence of the physical structure of the protein matrix on wheat hardness
Authors: Stenvert Nick L. , Kingswood Keith
Published: November 2006

The influence of a range of factors on wheat hardness was investigated with particular reference to the physical structure of the endosperm protein matrix. Differences in hardness were found to involve the continuity of the protein matrix and the strength with which it physically entrapped starch granules. The primary determinant of wheat hardness is genetically controlled and appears to relate to factors influencing the degree of compactness of endosperm cell components. Environment and protein content are also of significance in determining the extent to which an ordered structure forms.
In vitro hydrolysis of plant protein concentrate with papain
Authors: Nanda Chaman L. , Ternouth John H. , Kondos Alex C.
Published: November 2006

A method was tested for measuring in vitro papain proteolysis of extracted plant protein to products soluble in trichloroacetic acid. The effects of incubation time, temperature and enzyme concentration were examined. Maximum proteolysis (82.9%) was obtained at 70°C for 24 h and a ratio of papain/protein substrate of approximately 1:10.
Subcellular structures in fermenting cocoa beans. Effect of aeration and temperature during seed and fragment incubation
Authors: Biehl Böle , Passern Ulrike , Passern Detlef
Published: November 2006

Chemical reactions in cocoa seeds during fermentation and roasting may depend on post‐mortem structural changes in the mesophyll cells. Aeration, temperature and acetic acid concentration vary considerably during commercial fermentation. Light and electron microscopic studies of seeds after artificial fermentations give evidence that the kind and the degree of subcellular structural changes depend on these variations. At 50°C in the presence of acetic acid (35 mM/litre, pH 4.0) water‐containing compartments are destroyed shortly before the lipid vacuoles fuse. The hydrophilic particles of the plasm become dispersed within the lipid phase. These changes occur within 6–20 h independent of the presence of air. At 40°C in the absence of acetic acid (citric acid, pH 5.5) the seeds germinate and protein vacuoles in many cells of the mesophyll inflate considerably within 6 h, which is before post‐mortem structural changes, different from those following treatment in acetic acid at 50°C, become obvious. Incubation of cotyledon fragments instead of whole seeds submerged in buffer induced these structural changes as well and were even more pronounced. The significance of temperature differences in the range of 40–50°C and induction of germination during fermentation is discussed.
The sensory analysis and identification of volatiles from walnut (Juglans regia L.) headspace
Authors: Clark Richard G. , Nursten Harry E.
Published: November 2006

This paper has the two‐fold aim of illustrating the application of techniques recently developed in this laboratory and of elucidating the nature of the compounds responsible for the aroma of a particular foodstuff. The volatile constituents of Chaberté walnuts (Juglans regia L.) headspace were investigated using charcoal capillary traps. By means of capillary columns and a g.c.‐m.s. system some 37 compounds were identified, including six aldehydes, six alcohols, and five ketones. It was shown that the aroma of walnuts is composite in nature, since none of the components was found to possess a walnutty aroma on elution from g.c. columns, yet the total headspace, retrapped on a length of PLOT Celite capillary, was found to be extremely walnutty. Further sensory analysis using PLOT Celite traps revealed that the carbonyls present in a particular region of the chromatogram were important to the aroma of walnuts. A mixture in liquid paraffin of certain carbonyls identified in the headspace was found to possess a moderately walnutty aroma.
The effect of sodium dodecylsulphate on the optical rotation of crude ovalbumin at different temperatures
Authors: Hegg Per‐Olof , Löfqvist Bo
Published: November 2006

The effect of sodium dodecylsulphate (SDS) on crude ovalbumin (50 mg/ml) was studied in the temperature interval 20–80°C and at pH 7.5, by use of optical rotation measurements. It was found that in addition to the SDS‐induced conformational change at room temperature, there was at SDS concentrations below 100 mM, also a thermally induced conformational change. A concentration of SDS above 5 mM was found sufficient to prevent aggregation, and it is likely that this stabilisation towards aggregation is brought about by a destabilisation of one or several of the separate eggwhite proteins in the crude ovalbumin. A broader understanding of the results in terms of technical properties of food proteins is briefly discussed.
The effects of aqueous seaweed extract and kinetin on potato yields
Authors: Blunden Gerald , Wildgoose Paul B.
Published: November 2006

In a trial conducted in 1974, foliar application of an aqueous seaweed extract of known cytokinin activity produced a significant increase in the yield of potatoes of the variety King Edward. A synthetic cytokinin, kinetin, also produced significant increases in the yield of tubers of both the varieties King Edward and Pentland Dell. There was close correlation between the results from the use of kinetin and the seaweed extract of equivalent cytokinin activity, which suggests that the effect of the seaweed extract was due to its cytokinin content. In a complementary trial in 1975 with King Edward potatoes, significant increases were obtained again in tuber yields through treatment with aqueous seaweed extract. The major increase was in ware potatoes.
Potential phytotoxic components of pulverised fuel ash
Authors: Collier Graham F. , Greenwood Duncan J.
Published: November 2006

The release of aluminium, arsenic, boron, cobalt, copper, chromium, manganese, nickel, lead and zinc from pulverised fuel ash (PFA) and a standard Wellesbourne soil were studied by extraction with nitric acid and EDTA and by anaerobic incubation with grass meal. According to each of the criteria, only aluminium, arsenic, boron and copper were released in appreciably greater quantities from PFA than from soil. There were considerable variations in pH and the total content of soluble salts, mainly sodium, potassium, magnesium and calcium sulphates, between samples of ash. pH varied from 4.6 to 9.3 and the conductivity declined from 4.75 × 10−3 to 3.2 × 10−3 ohm−1 cm−1 with increased pH. The pH of the ash also influenced the concentration of other ions in water in equilibrium with it. When the pH was low the concentrations of aluminium and copper were large but those of arsenic were small. By contrast, when pH was high, the concentrations of arsenic were substantial and those of aluminium and copper small. The concentrations of boron, though always substantial, declined with increase in pH. It is concluded that, in addition to sulphate and boron, aluminium, copper and arsenic are potential causes of phytotoxicity.
The effects of sulphur fertilisers on the content of sulpho‐amino acids in seeds of cowpea (Vigna unguiculata)
Authors: Evans I. Marta , Boulter Donald , Fox Robert L. , Kang B. T.
Published: November 2006

Seed meals of three cowpea (Vigna unguiculata) cultivars, grown in pots containing sulphur‐deficient soil supplemented with 0, 0.2, 0.6, 1.8, 5, 15 and 45 parts/106 sulphate‐S levels in the soil solution, were examined for total nitrogen, total sulphur and sulpho‐amino acid contents. The sulphur content and the ratio of sulphur to nitrogen were found to increase with the increasing level of sulphate‐S fertilisation up to ca 5 parts/106. Compared with the control the sulpho‐amino acid content in seeds of cowpea TVu 76 increased with S‐supplementation up to 5 parts/106 and that of cowpea Sitao Pole increased with S up to 1.8 parts/106. Similar levels (7 and 2 parts/106 respectively) of sulphate‐S were required in the soil solution to obtain 95% of the maximum yields of cowpea seeds. The content of sulpho‐amino acids in the seeds from 5 parts/106 treatments were similar to those reported for cowpeas grown under field conditions at IITA and elsewhere with adequate levels of soil sulphur for maximum yield.
Viscosity of aqueous solutions of gum ghatti
Authors: Jefferies Martin , And Geoffrey Pass , Phillips Glyn O.
Published: November 2006

Gum ghatti contains a soluble gum and an insoluble gel which partially dissolves on boiling. Maceration of the gel in water gives a perfectly stable dispersion which for practical purposes behaves as a solution. The viscosity of the gel dispersion is ca 10–30 times that of the soluble gum. The proportion of gel in four commercial batches of gum ghatti varied from 8 to 23 %. The viscosity of the whole gum dispersion depends largely on the proportion of gel. The viscosity of gum ghatti can be closely controlled by blending to a fixed proportion of gel.
4‐methoxyallylbenzene: An important aroma component of apples
Authors: Williams Anthony A. , Tucknott Owen G. , Lewis Mervyn J.
Published: November 2006

Headspace collection techniques on whole apples, coupled with sensory evaluation, gas chromatography, gas chromatography‐mass spectrometry and infrared spectroscopy has enabled 4‐methoxyallylbenzene to be identified as a component contributing to the important spice‐like note in the aroma of a number of apple cultivars. This compound is present in varying amounts in all those examined but is more prominent in Ellison 's Orange, where it gives a recognisable aniseed‐like character to the aroma.
The effect of lipoxygenase action on the mechanical development of doughs from fat‐extracted and reconstituted wheat flours
Authors: Frazier Peter J. , Brimblecombe Felicity A. , Daniels Norman W. R. , Russell Eggitt Peter W.
Published: November 2006

The mechanism by which soya lipoxygenase enzyme action improves the Theological properties of wheat flour doughs during mechanical development in air has been investigated further. Free‐lipid extraction, reconstitution and replacement experiments have shown that the rheological effect of lipoxygenase action, which is consistent with an oxidative improvement of the dough proteins and may also result in extended mixing tolerance, only occurred in the presence of an oxidisable, polyunsaturated, free‐lipid substrate. Addition of this substrate in an oxidised state (produced either by autoxidation or enzyme‐oxidation) to doughs mixed from fat‐extracted flour under nitrogen resulted only in a small rheological improvement, greater for the autoxidised than the enzyme‐oxidised lipid, but in no way comparable with the large rheological effect of lipoxygenase action during dough mixing in air. Furthermore, the presence of an antioxidant, nordihydroguaiaretic acid (NDGA), during dough development, although greatly inhibiting peroxide formation, only marginally impaired the rheological improvement due to lipoxygenase action. Additional evidence is therefore provided for a coupled oxidation mechanism being responsible for the rheological effect, since lipoxygenase‐catalysed oxidation actively occurring in the dough during mixing appears to be the fundamental requirement, irrespective of whether the primary oxidation products lead to lipid peroxides or oxidised NDGA.
Levels of chromium in wheats and some other animal feedstuff 's in Australia
Authors: Jones Gordon B. , Buckley Reginald A.
Published: November 2006

The chromium contents of samples of wheat from the principal wheat‐growing areas of Australia were determined, and the ethanol‐extractable (GTF) chromium was determined in a number of these wheats. A variety of other animal feedstuffs were assayed in the same manner. The range of values for total chromium in the wheats was 4–98 ng/g, while the range of percentages of GTF chromium was 7–55 %. Other animal feedstuffs ranged from 20–1000 ng/g total chromium, and from 1 % (meat meal) to 57 % (wheaten hay) for GTF chromium.
The development of rancidity in husked and naked oats after storage under various conditions
Authors: Welch Robert W.
Published: November 2006

The levels of hydrolytic and oxidative rancidity have been estimated in husked and naked (huskless) oat varieties stored under different conditions, viz. (i) varying moisture content, (ii) varying oxygen availability, (iii) after bruising, and (iv) after drying at different temperatures. Hydrolytic rancidity increased at higher moisture contents and with storage period but generally the level in naked oats only exceeded that of husked oats if the grain was severely bruised. No oxidative rancidity was detected in husked or naked oats under any of the treatments used.
Prediction by leaf analysis of nitrogen fertilizer required for winter wheat
Authors: Batey Thomas
Published: November 2006

In 1966 and 1967, 12 experiments on winter wheat tested five rates of N applied in spring as NH4NO3. Leaf samples comprising all the above ground vegetation were taken on two dates in spring between 31 March and 18 May from a fixed area of crop grown without fertiliser N; the dry matter yield (DM, kg/ha) and N content (%) were determined. Between the two dates, DM increased and leaf N content decreased. From the response curves for N applied and grain yield, the optimum rate of fertilizer N required for maximum grain yield was obtained. The latter was used as a test of soil N availability and compared with the following values (i) content of N (%) in leaves at each sampling and its rate of decrease—no significant correlation, (ii) yield of leaf DM (kg/ha) at first sampling—no significant correlation, (iii) leaf DM yield at second sampling, significant (r= ‐0.678), and also rate of increase in DM (kg/ha per day, r= ‐0.711), (iv) leaf N offtake (kg/ha N) significant at first sampling (r= ‐0.607), second sampling (r= ‐0.744) and also rate of increase in N offtake (kg/ha N per day, r= ‐0.670). Crop growth in spring was related to N supply and it was shown that DM yield, leaf N offtake and their respective rates of increase could be used to assess the availability of N in the soil and to predict the amount of N fertilizer required in spring to obtain maximum grain yield.
Estimation of the fungal toxins, zearalenone and aflatoxin, contaminating opaque maize beer in Zambia
Authors: Lovelace Cheryl E. A. , Nyathi Clever B.
Published: November 2006

The concentration of zearalenone and aflatoxin was estimated in Zambian homebrewed and commercial opaque maize beer. Levels of aflatoxin were negligible. Zearalenone was present up to 4.6 mg/litre with a mean concentration of 0.92 mg/litre. Zearalenone was detected in the maize and maize malt used in beer preparation and it was found to dissolve preferentially in the liquid fraction of the beer. The concentration was related to the district of maize growth.
Light‐induced flavour deterioration. The effect of exposure to light of pork luncheon meat containing erythrosine
Authors: Chan Henry W.‐S. , Levett Gordon , Griffiths Nerys M.
Published: November 2006

When exposed to fluorescent light (250–1000 1x) at 4°C, luncheon meat containing erythrosine undergoes marked flavour deterioration in a few hours which is perceived mainly as a loss of flavour. The effect increased with light intensity and time of exposure but is absent in luncheon meat without added colours or with Red 2G in place of erythrosine. The results are consistent with the unique ability of erythrosine (amongst artificial food colours) to act as a sensitiser of photo‐oxidation.
Chemical studies with silage microorganisms in artificial media and sterile herbages
Authors: Kibe Kyuei , Matthew Ewart J. , McDonald Peter
Published: November 2006

The fermentation changes in artificial media and in sterile herbages inoculated with strains of yeast, hetero‐and homo‐fermentative lactic acid bacteria isolated from silage were studied in two experiments. In the first, using malt extract broth, four treatments were employed: aerobic, high level of glucose; aerobic, low level of glucose; anaerobic, high level of glucose; anaerobic, low level of glucose. The pH decreased in all cultures. There were no appreciable differences in pH among the cultures of the heterofermentative lactic acid bacterium, but in the cultures of the homofermentative organism there was a greater decrease in pH aerobically than anaerobically. The lowest pH values in the yeast cultures, occurred in the high glucose treatments both aerobically and anaerobically. In all the yeast cultures, acetic, propionic, butyric, isobutyric and isovaleric acids were present. The heterofermentative lactic acid bacterium produced only acetic acid, the greatest amount occurring under aerobic conditions. Ethanol was detected in the culture of the heterofermentative lactic acid bacterium but not in that of the homofermentative organism. Relatively large amounts of i‐pentanol were found in the aerobic yeast cultures. In the second experiment, inoculated grass was ensiled with similar treatments to those used in the first experiment. Two incubation periods, 3d and 10d were used. The pH values in all treatments were high (> pH 5.0). In aerobic conditions, the lactic acid contents after the 10d incubation were higher than after 3d. The losses of water soluble carbohydrates during fermentation were greater in the aerobic than anaerobic treatments. Acetic acid was present in all cultures but the higher volatile fatty acids (C3‐iC5) were only detected in appreciable amounts in the aerobically treated herbages after 10d. In addition to ethanol, n‐propanol and i‐butanol were also present in all the 10d anaerobic treatments. i‐Pentanol occurred in both the aerobic and anaerobic treated herbages.
The phytate and phytase of soybean tempeh
Authors: Sudarmadji Slamet , Markakis Pericles
Published: November 2006

Soybeans were fermented into tempeh by Rhizopus oligosporus NRRL 2710. The phytic acid content of soybeans was reduced by about one‐third as a result of this fermentation, while an equivalent amount of phosphate was released in the tempeh. The reduction of phytic acid was due to phytase elaborated by the mould of the fermentation. The pH optimum of this enzyme was 5.6 and the Km of the phytase‐phytate reaction was 0.28 × 10−3 M.
Preliminary investigations on some potential sources of protected methionine derivatives for ruminant rations
Authors: Buttery Peter J. , Manomai‐Udom Satit , Lewis Dyfed
Published: November 2006

A series of N‐substituted methionine derivatives were investigated for their potential to resist rumen degradation but still to release methionine in the duodenum. The method adopted was (a) to measure rumen methyl mercaptan concentrations in sheep following intraruminal doses of the materials and (b) to measure the ability of the materials to promote the growth of chicks receiving a methionine deficient diet.
Carbohydrates of rapeseed: A review
Authors: Siddiqui Iqbal R. , Wood Peter J.
Published: November 2006

Graded extraction of oil‐free, dehulled, rapeseed cotyledon meal with boiling aqueous ethanol, hot water, hot ammonium oxalate and finally sodium hydroxide yielded a series of fractions. The composition, identification and structural evaluation of the various products is presented and the results compared with those obtained from other seeds.
The temperature dependence of anaerobic glycolysis in beef muscle held in a linear temperature gradient
Authors: Jeacocke Robin E.
Published: November 2006

Measurements have been made of the rate of pH fall post‐mortem in excised beef sternomandibularis muscles held in a linear temperature gradient. A minimum rate of pH fall was observed between 10 and 12°C and the rate increased as the temperature was further reduced towards 0°C, a phenomenon known to be accompanied by cold‐shortening and attributable to increased activity of the contractile actomyosin ATPase which stimulates glycolysis. The increase in rate observed as the temperature was raised above the 10–12°C minimum, had an activation energy of 40kJ/mol, similar to that of the calcium‐independent myosin ATPase.
Effect of manuring and frequency of cutting on the yield of leaf protein from some fodder grasses
Authors: Balasundaram Coimbatore S. , Chandramani Rajaram , Balakrishnan Thillai , Krishnamoorthy Konnaiyur K.
Published: November 2006

A study to find out the effect of manuring and the frequency of cutting on the yield of leaf protein was conducted with four fodder grasses. The study revealed that Cenchrus glaucus was superior to the other grasses tried and it gave the maximum yield of dry matter and extractable protein. Farm yard manure at 10 tons/ha along with ammonium sulphate at 33 kg N/ha proved to be the best in giving the highest yield of dry matter and leaf protein. For all the grasses the maximum yield was found to range within the first three cuttings.
The influence of the variety of barley and level of nitrogen fertilisation on the digestibility and metabolisable energy value of barley meal in the pig
Authors: Peers David G. , Taylor Alexander G.
Published: November 2006

Metabolism studies were carried out with 45 kg pigs to examine barley meal from the varieties Golden Promise, Maris Mink, Lami, Zephyr and Abacus, all with similar nitrogen (N) content, and barley meal from the variety Zephyr which had received four different levels of N fertilisation. There were no significant differences (P > 0.05) between varieties for the apparent digestibility coefficients of gross energy (GE) and proximate constituents, the least significant difference for GE and N being 0.025 and 0.089 of the respective means. The mean digestible energy (DE) and metabolisable energy (ME) values were 14.48 and 14.07 MJ/kg dry matter (DM). The mean apparent digestibility of N was 0.685. The apparent digestibility coefficients of GE and N of meal from the variety Zephyr increased with N content. The increase in DE value with N content could be attributed to the increase in N digestibility.
Nutritional evaluation of kidney beans (phaseolus vulgaris): The toxic principle
Authors: Pusztai Arpad , Palmer Robert
Published: November 2006

Kidney bean (Phaseolus vulgaris) lectins were purified by affinity chromatography on a fetuin‐Sepharose‐4B column. The net protein utilisation (NPU) of rats fed on a 5% casein‐containing diet was strongly depressed by these pure lectin preparations. The extent of this nutritional toxicity was found to be related to the lectin content of the diet according to the following equation: NPU = NPU5% casein −280 x (where x is the lectin content in % w/w). Thus, because in addition lectin‐free kidney bean protein preparations were found to be non‐toxic for rats, it is now suggested that the toxic principle of kidney bean is identical with its constituent lectins.
A micro‐method for the estimation of oil content and composition in seed crops
Authors: Welch Robert W.
Published: November 2006

A method is described for the routine estimation of oil content and composition in seed crops by determination of the total and component long‐chain fatty acids. The oil was transmethylated without prior extraction using 2% H2SO4 in methanol at 80°C and the resultant fatty acid methyl esters separated and measured by gas‐liquid chromatography. The method was shown to be applicable to a wide range of samples including field beans, cereals and linseed, and for use with individual seeds or very small samples (e.g. half seeds). Results obtained with this method were highly reproducible, giving good recoveries of oil and individual fatty acids. The method gave values intermediate between those obtained by ether extraction and acid hydrolysis methods.
Effect of growth stage on the concentrations of various nitrogen fractions, including amino acids, in lucerne (Medicago sativa L.) cv aragón
Authors: Treviño Jesús , Hernández Maria T.
Published: November 2006

The concentrations of various nitrogen fractions were determined in lucerne cv Aragón. Variations in the total N, non protein N, nitrate and amino acids contents throughout the growing period of lucerne are described. The concentrations of different nitrogen fractions in the dry matter decreased as forage age advanced.
Tests of long‐term residues of phosphorus fertiliser
Authors: Sparrow Philip E. , Russell Richard D.
Published: November 2006

Four experiments with maincrop potato were done in 1973 to compare the residual values of two amounts of four forms (Dicalcium phosphate, Superphosphate, Gafsa— Ground mineral phosphate, Basic slag) of phosphorous fertiliser given from 1951 to 1971. The residues were evaluated by test dressings of nil, 37.5 and 75 kg/ha P2O5 as superphosphate; to make the results as comparable as possible at each site the new P was thoroughly incorporated into the soil. Residues increased yields on all sites; effects were small except at Rosemaund Experimental husbandry farm (EHF) where residues alone increased yields by 8.6 t/ha. Apart from Ground mineral phosphate, which had little effect except at Rosemaund, yield differences resulting from forms of P fertiliser were small. Apart from at Rosemaund EHF the rate of response to the freshly applied phosphate was unrelated to the available soil P. In terms of fresh dressings residues were equivalent to about 8 % (80 kg P2O5ha) of accumulated total dressings.
Changes in the muscle of lemon sole (Pleuronectes microcephalus) after very long cold storage
Authors: Kim Hak‐Kyoon , Robertson Ian , Malcolm Love R.
Published: November 2006

The solubility of Lemon Sole muscle in 5% sodium chloride after storage at — 14 to — 15°C was shown to fall to the same minimum level as that of cod, but the reaction was very much slower. After storage for 5 years the protein had still been fairly soluble, and appeared to have reached the asymptote, but in the present experiment the fish were stored for over 17 years and the reaction was now evidently complete. It is complete in cod at this temperature in about 15 weeks.
Influence of cassava diets on placental thiocyanate transfer, tissue rhodanese activity and performance of rats during gestation
Authors: Tewe Olumide O. , Maner Jerome H. , Gomez Gulliermo
Published: November 2006

Two nineteen day rat gestation/metabolic studies were carried out with thirty female rats to investigate the influence of fresh and dried cassava containing 173 parts/106 and 92 parts/106 HCN respectively on placental thiocyanate transfer, metabolic changes in maternal and foetal tissues and their gestational performance. The cassava diets caused marked changes in the weight gain and thiocyanate concentration of the urine and serum of the gestating rats. Amniotic fluid thiocyanate was significantly increased by the fresh cassava diets (P<0.01), but foetal thiocyanate was not significantly different between treatments (P>0.05). Rhodanese activity and fresh weights of maternal and foetal tissues were also not significantly affected by the cassava diets (P>0.05).
A sequential analytical method for the howard mould count test of tomato products
Authors: Basker Dov , Dolev Danny , Gillist Joseph
Published: November 2006

The Howard Mould Count of tomato products, as generally performed, was considered, and an approach was sought which would give greater reliability while reducing the number of fields which need to be examined. A sequential analytical method was developed and applied. The equations of the sequential acceptance/rejection lines were converted to graphical form for direct laboratory use, at various maximum Mould Count limits. The procedure is explained and illustrated. For screening purposes, reliable results will often be obtained even when the number of fields examined is below the minimum (50) required by the official procedure; for regulatory purposes, a test may require more than 50 fields to be examined in order to give a reliable result, but less than an arbitrary set number (say, 100) from every sample.
Prediction of the digestibility of the dry matter of tropical forages from their solubility in fungal cellulase solutions
Authors: Adegbola Anthony A. , Paladines Osvaldo
Published: November 2006

Correlations between in vitro dry matter (DM) digestibility and amount of DM dissolved in acid pepsin and cellulase enzymes for 24 tropical forage samples gave a value of 0.91 but a high sample standard deviation of 6.50 and a coefficient of variation of 25 %. This suggests that the cellulase technique requires further study if it were to be used as a predictor of rumen liquor in vitro digestibility values for tropical grasses and legumes. An improved correlation of r = 0.98 with sample standard deviation of 2.29 was obtained when percent DM dissolved in acid‐pepsin and cellulase enzymes was compared with the in vivo dry matter digestibility values of 11 tropical forage grasses and legumes. This result suggests that the pepsin‐cellulase technique may be used to predict in vivo DM digestibility values in tropical grasses and legumes.
Isolation of two γ‐gliadins from cappelle‐desprez
Authors: Ewart John A. D.
Published: November 2006

The strongest band in the electrophoretic pattern of Cappelle‐Desprez gliadin owes its intensity to the coincidence of two proteins. These have been isolated and characterised. They have a fairly similar amino acid composition, typical of the gliadin class, and appear to be single polypeptide chains, free of SH groups and carbohydrate. Their molecular weights are 38 000 and 44 000. The higher mobility at pH 8.9 of the lighter molecule is attributed to its smaller size though the possibility also exists of its having fewer COO‐ groups. The equal mobility at acid pH arises because the extra resistance encountered by the larger molecule is balanced by a higher positive charge due to histidine. The proteins appear to correspond to the γ2 and γ3 Ponca gliadins isolated at Peoria, and this supports the idea that gliadins of equal mobility from different varieties have very similar structures. A rapid way of calculating recovered protein is mentioned.
A cappelle‐desprez β‐gliadin
Authors: Ewart John A. D.
Published: November 2006

A β‐gliadin from Cappelle‐Desprez wheat has been purified sufficiently to be analysed. Its amino acid composition is typical of the gliadin class. The molecule appears to be a single polypeptide chain with no carbohydrate or SH groups and a molecular weight of 38 000.