bluuebunny/crossref_metadata_2025 huggingface dataset:
Sorghum cultivar verification by electrophoresis
Authors: Taylor John R. N. , Schussler Lottelore
Published: October 2006

After comparing the merits of three different electrophoretic methods of separating cereal prolamins, a procedure for sorghum cultivar verification by urea‐polyacrylamide gel electrophoresis has been developed.

The problem of the tannins in high‐tannin (bird‐resistant) cultivars rendering the prolamins insoluble has been overcome by extracting the proteins in the presence of polyvinylpolypyrrolidone.

As with other cereals, the electrophoretic pattern of the prolamins was unaffected by the environment in which the plants were grown. Further, the pattern was not affected by long‐term storage of the grain, and cultivars appear to remain unique with respect to their prolamin proteins through many generations.
Effects of intraruminal administration of polyol to sheep
Authors: Lister Cliff J. , Smithard Ronald R.
Published: October 2006

In‐vitro incubations were used to study the effect of intraruminal administration of a mixture of the polyhydric alcohols, arabinitol, xylitol, galactitiol, mannitol and sorbitol, on fermentation pattern and the fate of the polyhydric alcohols. Incubations were carried out with rumen fluid taken from sheep before receiving polyol and after 2 and 3 weeks of intraruminal administration of 2.12 g polyol DM/kg live wt.0.75 per day to observe effects of adaptation. Inclusion of polyol in incubations with unadapted rumen fluid had little effect on the volatile fatty acid pattern. However, with adaptation there was a shift in the fermentation pattern in the presence of polyol towards a higher acetate: propionate ratio. The hexitols rapidly disappeared in all the incubations, while the pentitols were more resistant to fermentation. Significantly faster fermentation of arabinitol by rumen fluid from sheep which had received polyol indicated that adaptation had taken place. In the incubations with adapted microbes, xylitol was significantly more resistant to fermentation than arabinitol; after 6 h incubation, approximately half the xylitol and only one fifth of the arabinitol remained unfermented.

Analysis of duodenal digesta from adapted sheep which were receiving polyol showed that most of the small amount of pentitol which entered the small intestine did so within 2–3 h of dosing. Despite the apparent resistance of pentitols to rumen fermentation, only 1.0% of the arabinitol and 1.8% of the xylitol in the daily dose entered the small intestine.
Effect of contamination of foods by Aspergillus flavus on the nutritive value of protein
Authors: Ostrowski‐Meissner Henry T.
Published: October 2006

The effect of aflatoxin was measured on the protein quality of peanut meal (PNM) and fish meal (FM) Total protein efficiency, protein efficiency ratio, net protein utilisation, examination of the histopathology of the liver, ileal digesion of amino acids and plasma amino acid concentration were used as bioassays together with chemical score (CS), dye binding capacity (DBC), essential amino acid index (EAAI), and discriminant computered PER (DC‐PER) as chemical methods.

In trial 1, aflatoxin‐free PNM was compared with infected PNM at graded levels of toxin when fed to chickens and ducklings. In trial 2, various mixtures of PNM and FM at a constant aflatoxin level (280 μg kg−1) were fed to compare the effects of aflatoxin on proteins of differing quality.

Ducks were more sensitive to the toxin than chickens, as indicated by deterioration of protein quality, and the effects on growth and the histological appearance of the liver were magnified on diets of low quality (PNM), but not of high quality (FM). Contamination of PNM resulted in progressive increase in DBC and, to a lesser extent, in DC‐PER, while EAAI and CS were not affected.

The importance of these findings lies in the problems of mould contamination of animal feedstuffs in humid, tropical conditions, which may affect the more sensitive animals, and may not be detected by chemical methods of measuring protein quality, nor by bioassay on chickens, if the levels of contamination are low.
Biodegradation of caffeine: Formation of theophylline and theobromine from caffeine in mature Coffea arabica fruits
Authors: Suzuki Takeo , Waller George R.
Published: October 2006

The level of theophylline in mature and ripened fruit is 20–50 times that in the immature green fruit of Coffea arabica L. Biodegradation of caffeine occurs in the mature, ripened coffee fruits through theophylline and theobromine as the first biodegradation products. It is now clear that theophylline is associated primarily with caffeine biodegradation, whereas theobromine is involved in both biosynthesis and biodegradation of caffeine.
The metabolisable energy value of foods
Authors: Miller Derek S. , Judd Patricia A.
Published: October 2006

Methods for calculating the Metabolisable Energy (ME) of foods and diets are reviewed in the light of the current interest in diets high in dietary fibre.

A new equation is proposed for the calculation of ME, taking into account the dietary fibre content of foods and its effects on the digestibility of proximate sources of energy. The equation has been tested against values for the ME of various diets determined by balance studies in human subjects, and gives results which agree within 3%. This agreement is much closer than that obtained with the other available methods for calculating ME, including those currently in use.
The intravenous halothane test as an experimental method for quantifying stress sensitivity in pigs
Authors: Gregory Neville G. , Wilkins Lindsay J.
Published: October 2006

The venous blood pH, pCO2, lactate, pyruvate and haematocrit responses to an intravenous (i/v) infusion of halothane‐lipid emulsion were assessed in Pietrain, Pietrain X Norwegian Landrace and Gloucester pigs. Halothane‐induced lactacidosis was dose related in the Pietrain (stress sensitive) pigs between 0 and 82 μl halothane kg−‐1, whereas the crossbred and Gloucester pigs did not show any lactacidosis. It is concluded that the i/v halothane test can be used to quantify a stress sensitive pig's reaction to the drug, and that the crossbred pig does not express halothane sensitivity even at a mild level. Carazolol pretreatment in Pietrain pigs increased the halothane‐induced lactacidosis, whereas in a separate study carazolol was found to decrease their rate of post‐mortem muscle acidification. This indicates that halothane activates a different mechanism from stress when inducing lactacidosis in stress sensitive pigs.
Myosin denaturation in pale, soft, and exudative (PSE) porcine muscle tissue as studied by differential scanning calorimetry
Authors: Stabursvik Eva , Fretheim Kristen , Frøystein Terje
Published: October 2006

Myofibrillar tissue from pale, soft, and exudative (PSE) pork was compared to tissue from normal pork by differential scanning calorimetry at pH 5.4. Thermograms of myofibrillar tissue from normal pork were characterised by three major peaks with temperature maxima at 58 and 66°C, associated with myosin denaturation, and at 78°C, associated with actin denaturation. In thermograms of PSE pork, the peak at 58°C was markedly reduced, and appeared as a shoulder. When the thermograms were divided into segments corresponding to the three major peaks, the area of the low temperature myosin segment was shown to be reduced by about 50% in PSE pork, as compared to normal pork. This indicates approximately 50% denaturation of the least thermostable parts of the myosin molecule. The more thermostable parts of the myosin molecule were largely unaffected, as was actin.
Comparison of water‐insoluble phosphate fertilisers with superphosphate—a review
Authors: Davies Garth R.
Published: October 2006

A series of experiments was carried out in England and Wales in the period 1972–1982, to compare the relative effectiveness of various commercially available water‐insoluble phosphate fertilisers with that of superphosphate. Most of the trials were on permanent grassland, but a few used barley and swedes as test crops. Ground Gafsa rock P, although only approximately 50% as effective as superphosphate in the year of application, gave somewhat higher responses in the following (residual) 2 years on unlimed, acid grassland. In these circumstances, grinding finer than 150 μm did not appear to be worth the extra cost. Granulation of finely ground Gafsa rock P slightly reduced its effectiveness for grass in the first year, but markedly reduced its efficiency for cereals. Mixtures of medium grade basic slag and Moroccan rock P were only slightly inferior to high grade basic slag, but mixtures of low grade slag and ground rock P (Moroccan or Gafsa) were somewhat less effective than the finely ground Gafsa rock P, especially in the first year. Granulated ground underacidulated rock P (Gafsa or Moroccan), was as effective as very finely ground Gafsa rock P, however a bulk blend of granulated Gafsa rock P and triple superphosphate was more effective than Gafsa rock P, but less so than superphosphate in the first year. Calcined aluminium calcium P was the least effective of the fertilisers tested, being especially slow in action, and only 25% as effective as superphosphate in the first year.
The interaction between fusaria and their mycotoxins in grass silage
Authors: Damoglou Anthony P. , Shannon Wesley , Downey Gerard A.
Published: October 2006

Perennial ryegrass was inoculated with a mycotoxigenic strain of Fusarium roseum or F. tricinctum and ensiled in laboratory silos to study the ability of the fungi to grow and produce toxin. Neither strain persisted in the silage or produced toxin. The addition of preformed toxin to the grass produced no detectable detrimental effect on the overall fermentation process.
The high performance liquid chromatographic determination of total malondialdehyde in vegetable oil with dansyl hydrazine
Authors: Hirayama Teruhisa , Yamada Naohide , Nohara Motoshi , Fukui Shozo
Published: October 2006

A simple high‐performance liquid chromatographic (h.p.l.c.) method has been developed for determining total malondialdehyde (MDA), including free MDA and MDA released from its precursor in vegetable oils. Free MDA was reacted with dansyl hydrazine in an acidic medium, and the product, 1‐dansyl‐pyrazole(DP), was determined by h.p.l.c. The reaction releasing MDA from its precursor requires Fe3+ in 5% hydrochloric acid medium. Recoveries of free MDA and tetramethoxypropane (used as an MDA precursor) in vegetable oils were satisfactory. During autoxidation, a remarkable difference between the DP values of methyl oleate, methyl linoleate and some vegetable oils, and that of methyl linolenate was observed. Only methyl linolenate released MDA during autoxidation. For autoxidised methyl linolenate the DP value correlated with the thiobarbituric acid(TBA) value, although the DP value was only 30% of the TBA value.
Differential scanning calorimetric study of muscle and its proteins: Myosin and its subfragments
Authors: Wright David J. , Wilding Peter
Published: October 2006

The thermal denaturation of rabbit skeletal muscle myosin and its subfragments was investigated by differential scanning calorimetry. The thermal denaturation of myosin was shown to occur via three (at least) partly independent cooperative endothermic processes. The temperatures at which these processes occurred (312, 317 and 323 K at pH 6.0 and I=1.0) were shown to vary with pH (5.5–8.0) and I (0.05–1.0). The apparent enthalpy of denaturation of myosin was also shown to be dependent on pH and I. By comparing thermograms of myosin with those of the isolated myosin subfragments, the three major processes associated with the thermal denaturation of rabbit myosin could be tentatively assigned to different regions of the myosin molecule, namely, the helical tail, the ‘hinge‐region’ and the globular heads. The ‘hinge‐region’ thermal denaturation was shown to be reversible at pH 6.0 and I=1.0. Investigations of the effects of ortho‐, pyro‐, and tripolyphosphate on the thermal denaturation of myosin showed that added pyrophosphate destabilised the myosin molecule by about 9 K compared to the effects of ortho and tripolyphosphate, even though the latter was probably hydrolysed to ortho and diphosphate.
Effect of seed lectins from Phaseolus vulgaris on the development of larvae of Callosobruchus maculatus; mechanism of toxicity
Authors: Gatehouse Angharad M. R. , Dewey Frances M. , Dove John , Fenton Katherine A. , Pusztai Arpad
Published: October 2006

Seeds of the kidney bean (Phaseolus vulgaris) are toxic to developing larvae of the bruchid beetle (Callosobruchus maculatus), a major storage pest of many legumes. Insect feeding trials were carried out whereby the albumin and globulin protein fractions from seeds of P. vulgaris were incorporated into artificial seeds. Both fractions were shown to be toxic and to contain haemagglutinating activity, implicating the seed lectins as being involved in seed resistance. Further feeding trials using different P. vulgaris lectin preparations confirmed the toxicity of these lectins and suggested that it was the E‐type lectin subunits (erythrocyte‐binding) which were the major antimetabolites. Indirect immunofluorescence investigations using monospecific antisera for globulin lectins showed that the lectins, when ingested by the larvae, bound to the midgut epithelial cells. It was suggested that the mechanism of lectin toxicity in this instance is analogous to that known to occur in the rat, namely that the ingested lectin causes disruption of the epithelial cells of the larval midgut leading to breakdown of the transport of nutrients into these cells, and the absorption of potentially harmful substances. This is the first time that evidence for the mechanism of lectin toxicity has been obtained in insects.
The physico‐chemical composition of New Zealand lemon oil
Authors: Lodge Norman , Paterson Vivienne J. , Young Harry
Published: October 2006

Physical and chemical characteristics of cold‐pressed lemon peel oil from New Zealand lemons were determined. Combined gas chromatographic and mass spectrometric techniques showed that the low optical rotation (αD20 =+53.3) was due to a higher β‐pinene to limonene ratio than is usual in cold‐pressed lemon oils from other countries. The results of analysis indicate that the New Zealand oil has a high quality and a high commercial value.
The trypsin and chymotrypsin inhibitor activities of various pea (Pisum spp.) and field bean (Vicia faba) cultivars
Authors: Griffiths D. Wynne
Published: October 2006

Eighteen pea and five field bean varieties were analysed for trypsin inhibitor activity. Considerable variation was found between pea varieties, the values ranging from 0.15 to 4.62 TIU mg−1 under the assay conditions used. However, all the pea varieties, with the exception of Progretta and Maro, had a lower trypsin inhibitor content than the average value (1.49 TIU mg−1) obtained for the field bean varieties. The same varieties were also examined for chymotrypsin inhibitor activity and again considerable inter‐varietal variation was found. Chymotrypsin inhibitor activity was significantly higher for all the pea varieties, with the exception of the variety Minerva, than that found for the field bean varieties. Both trypsin and chymotrypsin inhibitor contents appeared to be independent of crude protein content and other seed characteristics, and in both species these protease inhibitors were largely unaffected by dry heat but were rapidly denatured by autoclaving. The significance of these results with respect to the potential of improving nutritive value by plant breeding are discussed.
A new hydrolysis technique for steroid glycoalkaloids with unstable aglycones from Solanum spp.
Authors: Van Gelder Wim M. J.
Published: October 2006

The acid hydrolysis of different types of Solanum steroid (glyco)alkaloids, solanine, solanidine, solasodine, demissine and tomatine was studied with various reaction times and acid concentrations. Recovery of aglycone varied considerably; in particular, the aglycones of solanine and tomatine were unstable, even under mild conditions. None of the procedures was suitable for the simultaneous hydrolysis of the different types of glycoalkaloids. A new hydrolysis technique was developed, using a two‐phase system. This system consisted of an aqueous acid phase, in which the substrate was hydrolysed, and an immiscible organic liquid phase. This apolar organic liquid served as a protective phase for the unstable apolar aglycones. The recoveries of the two‐phase hydrolyses were near 100%, regardless of the type and purity (presence or absence of tuber extracts) of glycoalkaloid. Varying the organic phase caused a controllable change in liquid‐liquid partition of glycoalkaloids, aglycones and dehydrated derivatives, allowing the quantitative formation of the desired hydrolysis product. This new hydrolysis technique will improve the current methods of estimating total glycoalkaloids in Solanum spp. The applicability of this technique in estimating cardiac glycosides and for the production of raw steroid material for the pharmaceutical industry is discussed.
Autolysis of phytic acid and protein in canola meal (Brassica spp.), wheat bran (Triticum spp.) and fish silage blends
Authors: Stone Frederick E. , Hardy Ronald W. , Spinelli John
Published: October 2006

Fish silage, canola meal, and wheat bran were blended to form an acid‐stabilised, paste‐like product. Changes in protein nitrogen, non‐protein nitrogen, phytic acid, and orthophosphorus contents of the acidified blends were measured over a 5‐week period of storage at room temperature (20–22°C). During the storage period, phytic acid from the canola meal was dephosphorylated by phytase from the wheat bran. Changes in the level of non‐protein nitrogen showed that the fish proteins were partially hydrolysed and liquefied during storage, and that the fish enzymes may have partially hydrolysed the canola meal and wheat bran proteins. The resulting product could be stored at room temperature without spoiling and could be dried in conventional drying equipment. This process provides a means of improving the nutritional value of canola meal by reducing its high phytate content, and of producing a homogeneous dry feed commodity from liquid fish silage.
Peach palm (Bactris gasipaes H.B.K.), a new source of vegetable oil from the wet tropics
Authors: Arkcoll David B. , Aguiar Jaie P. L.
Published: October 2006

Fruit bunches of Bactris gasipaes have been analysed in an attempt to select for high oil content. Bunches varied in weight from 1.4 to 19 kg, of which 86–96.8% was fruit. They held 8–420 fruit of 6.7–244.4 g. Fruit size varied from 1 to 9 cm in diameter, and contained 3.8–225.1 g of mesocarp. The latter, together with the thin exocarp, represented 73.4–98.4% of the fruit weight in seeded fruit. This pulp contained 17.8–74.8% dry matter which consisted of 3.1–14.7% protein, 2.2–61.7% oil, 14.5–84.8% starchy N‐free extract, and 5.2–13.8% fibre. Some mesocarps also had very high levels of carotene (0–70 mg 100g−1 fresh weight) and oxalate‐like crystals were frequently found, especially in and just under the exocarp. Oil contents increased with fruit maturity and also varied a little with bunch and season. The best introduction could produce 34.3% oil per bunch plus 21.3% of a dry meal containing 22.6% protein and 35.8% fibre, plus 4.3% dry kernels containing 21% oil. This very high oil content is well above previous results and suggests that the species might become a useful alternative oil source in the wet tropics, once the character is combined with high field yields. In addition, the oil residue could be used as animal feed or even for human consumption, especially after separating out large fibre particles.
The influence of air temperature and relative humidity on milling performance and flour properties
Authors: Hook Simon C. W. , Bone Geoffrey T. , Fearn Thomas
Published: October 2006

Three wheats, one Canadian and two from the UK, were used to investigate the effect of ambient temperature and relative humidity (r.h.) on milling performance and flour properties. When the temperature was varied from 25 to 15°C, a decrease in ambient temperature was accompanied by an increase in extraction rate but no change in flour moisture content. When the r.h. was varied from 70 to 50%, a decrease in r.h. was accompanied by an increase in extraction rate and a decrease in flour moisture content. Changes in r.h. had a greater influence on milling performance and flour properties than did changes in ambient temperature.
A comparison of various extractants for the estimation of extractable zinc in cacao‐growing soils of south‐western Nigeria
Authors: Chude Victor O. , Gabriel Obigbesan O.
Published: October 2006

Forty‐six soil samples from cacao plantations located in South‐western Nigeria were analysed for extractable zinc by four methods, namely, ammonium acetate, dilute hydrochloric acid, magnesium chloride and diethylenetriamine pentaacetic acid (DPTA). Guinea corn (sorghum) was grown as a test crop. Relations among soil test methods, plant zinc uptake, and soil properties were examined by simple and multiple correlation analyses. The Zn extracted was in the following order: 1.0N NH4OAc>0.1N HCl>2N MgCl2>0.005M DTPA. The only correlation between extracts that was significant at the 5% level was between NH4OAc and DTPA extractable Zn. No soil properties except iron and aluminium oxide were significantly correlated with soil test values. Silt, clay and silt plus clay were correlated at 5, 5 and 1% respectively with Zn uptake, but pH was not. Zinc uptake by the plant was more closely correlated with 2N MgCl2 extractable Zn (r=+0.389) than with 1N NH4OAc extractable Zn (r=+0.291); 0.1N HCl extractable Zn (r=+0.079); or with DTPA extractable Zn (r=+0.220). The best prediction of uptake by plants was observed in multiple regression analyses involving combination of MgCl2 extractable Zn, pH, organic matter, and silt plus clay fraction (r=+0.601).
Distribution of insoluble bound phenolic acids in barley grain
Authors: Nordkvist Erik , Salomonsson Ann‐Christine , Åman Per
Published: October 2006

Insoluble bound phenolic acids were analysed by g.l.c. and by h.p.l.c. in eight abraded fractions of barley grain. Vanillic, p‐coumaric, ferulic and diferulic acids were identified in all the fractions. Ferulic and p‐coumaric acids were quantitatively the most important. The outer layers, comprising husks, pericarp, testa and aleurone cells, contained the highest concentrations of total phenolic acids (0.6–0.9%) while their concentrations were considerably lower in the endosperm layers (0.1% or less). Calculated on the basis of the cell wall content in the fractions, the highest concentration of ferulic acid was found in fractions enriched with aleurone cells while the highest concentration of p‐coumaric acid was found in fractions containing high levels of husks.
The effect of irradiation on technological properties and protein solubility of broiler chicken meat
Authors: Zabielski Jan , Kijowski Jacek , Fiszer Włodzimierz , Niewiarowicz Adam
Published: October 2006

During investigations on the effects of irradiation of chicken meat it was found that a 5 kGy dose of gamma 60Co radiation brings about a statistically significant (P<0.05) increase in free water content, and fall in water holding capacity and water retention capacity, in breast muscles of broiler chickens. The cause of deterioration of hydration properties in meat is a decrease in solubility of the protein fractions after irradiation. The relative protein extractability Y (in 0.1M phosphate buffer+1.1M KI) fell in a linear manner with increase in the radiation dose D according to the equation Y=98.494–0.838 D. The changes in sarcoplasmic fraction extractability Y in 0.03M phosphate buffer are described by the equation Y=101.615–0.515 D, and those of myofibrillar fraction by Y=100.377–1.628 D. Electrophoresis of the protein fraction (soluble in phosphate buffer+1.1M KI) on polyacrylamide gel (with SDS) indicated that the lowest extractability, as compared with untreated samples, was shown by myosin. Other protein solubilities were only slightly altered by the 5 and 10 kGy doses.
Effect of olive collection regime on olive oil quality
Authors: Kiritsakis Apostolos , Markakis Pericles
Published: October 2006

The titratable acidity and the peroxide value of olive oil extracted from olives harvested by shaking the trees over subtented nets increase rapidly as the residence of the fruit on the nets is prolonged. It is recommended that the extraction of the oil from the fruits is not delayed for longer than 2 to 3 weeks.
Preliminary studies on the effects of copper, iron and manganese ions on the degradation of 3‐indolylmethylglucosinolate (a constituent of Brassica spp.) by myrosinase
Authors: Searle Linda M. , Chamberlain Keith , Butcher Dennis N.
Published: October 2006

Copper (I and II) and iron (II and III) ions had qualitatively similar effects on the degradation of radiolabelled 3‐indolylmethylglucosinolate. In the presence of myrosinase they increased the production of 3‐indolylacetonitrile (IAN) largely at the expense of ascorbigen (ASC). With the addition of these metal ions the ratio of IAN to the products of the alternative pathways (3,3′‐diindolylmethane, ASC and formaldehyde) decreased as the pH increased from 4 to 7. These ions also led to a small increase in the non‐enzymic production of IAN.
Glucosinolates in Brassica vegetables. Analysis of twenty‐seven cauliflower cultivars (Brassica oleracea L. var. botrytis subvar. cauliflora DC)
Authors: Sones Karen , Heaney Robert K. , Roger Fenwick G.
Published: October 2006

The glucosinolate content of 27 cultivars of commercially grown cauliflower have been determined. The levels of total glucosinolates (<120 mg 100 g−1 fresh wt) were comparable with those previously reported for cabbage, but much lower than those found in Brussels sprouts. The major individual glucosinolates were identified as those possessing prop‐2‐enyl‐, 3‐methylsulphinylpropyl‐, 3‐indolylmethyl‐ and 1‐methoxy‐3‐indolylmethyl‐ side chains. Smaller amounts of but‐3‐enyl‐, 2‐hydroxybut‐3‐enyl‐, 3‐methylthiopropyl‐, 4‐methylthiobutyl‐, 2‐phenylethyl‐, pent‐4‐enyl‐, 2‐hydroxypent‐4‐enyl‐ and 5‐methylthiopentyl‐glucosinolates were also measured in some cultivars, the last three compounds not previously having been reported in cauliflower. Environmental effects, determined for the cultivars Wallaby, Coolabah, Barrier Reef and Snowy River were much less than previously found in Brussels sprouts.
Analysis of cereals, malted foods and dried legumes for N‐nitrosodimethylamine
Authors: Weston Roderick J.
Published: October 2006

A number of products manufactured from cereals, including malted breakfast foods, together with a malt extract, malt vinegar and dried peas and beans were analysed for N‐nitrosodimethylamine (NDMA). The only significant results were the levels of NDMA detected in wheaten cornflour (4.2μgkg−1) and in maize meal (2.6μgkg−1). The occurrence of nitrosamines in cereals may be due to the pre‐storage drying of grain in oil or gas‐fired kilns.
Screening for mutagens in norwegian foods by the ames test
Authors: Heriksta Hallgeir
Published: October 2006

Twelve Norwegian food products prepared in an ordinary domestic manner, were screened for mutagenic activity towards Salmonella typhimurium strains. Mutagenic activity towards the frameshift mutations strains (TA1538 and TA98) was observed in the basic organic extracts from fried fish cakes and fish pudding. Metabolic activation with rat liver homogenate (S9) was required. The ten other food items studied were found to be devoid of mutagenic activity.
Vitamin A activity in foods of animal origin
Authors: Sivell Lorna M. , Bull Nicola L. , Buss David H. , Wiggins Robert A. , Scuffam David , Jackson Patricia A.
Published: October 2006

The vitamin A activity of 246 samples of 59 different foods of animal origin was determined by high performance liquid chromatography. Wherever possible, the amounts of all‐trans retinol, 13‐cis‐ retinol, dehydroretinol, retinaldehyde and β‐carotene were measured. The relative activity of these components is discussed, and the results compared with previous estimates of the vitamin A content of these foods.
Kinetic study of the effects of extracts from Vicia faba var. equina on intestinal sugar absorption
Authors: Barcina Yolanda , Alcalde Ana I. , Ilundain Anunciación , Larralde Jesús
Published: October 2006

Alcoholic and water extracts from seed‐coats of Vicia faba var. equina were prepared and their effects on in‐vivo intestinal sugar absorption across the rat small intestine were investigated. Both extracts significantly (P<0.001) inhibited sugar absorption. The higher and more stable inhibition was induced by the water extract. Pretreatment of the extracts with polyamide significantly (P<0.001) reduced their inhibitory potency but did not abolish it, suggesting the presence in the extracts of some other intestinal sugar absorption inhibitor, different from polyphenols. Although both extracts inhibited intestinal sugar active transport, only the water extract was able to reduce sugar diffusion across the small intestine. These differences in behaviour seem to be related to the polyphenolic content of each extract.
Effect of soluble salts on water absorption by gel‐forming soil conditioners
Authors: Johnson Michael S.
Published: October 2006

The use of gel‐forming synthetic polymers as aids to water retention in sandy soils is an important development to assist plant growth in arid regions. However, the water storage properties of these soil conditioners are significantly affected by the nature and concentrations of dissolved salts in irrigation waters. Moreover, the salt response of products in the three main chemical families—starch copolymers, polyvinylalcohols and polyacrylamides—is very different, emphasising the importance of detailed assays in selecting a product for a particular set of environmental conditions.
Production of high‐fructose rice syrup and high‐protein rice flour from broken rice
Authors: Chen Wen‐Pin , Chang Yung‐Chi
Published: October 2006

The objective of this study was to develop a process for the production of both high‐fructose rice syrup and high‐protein rice flour from broken rice. The rice flour was obtained from broken rice by using either a dry or wet milling method. The glucose produced from the slurry of various raw materials by treating with α‐amylase and glucoamylase was compared. Results indicated that cassava and corn starch were better raw materials than rice flour. However, the filtered residue of liquefied rice slurry could be recovered as high‐protein rice flour. The particle size of rice flour had a small effect on the glucose yield. The orthogonal‐array table (L27) method of experimental design was employed to determine optimum conditions for liquefaction. The glucose yield based on starch was 90.8±3.6% under the following optimum conditions α‐amylase, 0.12%; rice flour, 20%; temperature, 96°C; time, 90 min. The filtrate from liquefied rice slurry was saccharified at 60°C with three different concentrations of glucoamylase. The higher the enzyme concentration, the shorter the time required to reach the maximum yield. After saccharification, the glucose solution was decolourised, desalted and concentrated to 40% d.s. and then isomerised to fructose at 60°C under continuous operation by using immobilised glucose isomerase packed in a column. The isomerised syrup was then purified and concentrated to 71% d.s. The final high‐fructose rice syrup contained 50% glucose, 42% fructose and 3% maltose. After liquefaction, the rice slurry was centrifuged and the precipitate was dried by either spray or drum drying. The composition of these two high‐protein rice flours was almost the same and the protein content was about three times as high as the raw material. There were significant differences in surface structure of rice flour and high‐protein rice flours, as observed by the scanning electron microscope.
Determination of volatile carboxylic acids (C1–C5i) and lactic acid in aqueous acid extracts of silage by high performance liquid chromatography
Authors: Canale Andrea , Valente Maria E. , Ciotti Angelo
Published: October 2006

A simple isocratic h.p.l.c. technique was developed for the simultaneous quantitative analysis of lactic, formic, acetic, propionic, isobutyric, n‐butyric and isovaleric acids in aqueous acid extracts of silage. An Aminex HPX‐87H strong cation exchange resin column at 41°C, 0.0025M H2SO4 mobile phase and ultraviolet detector at 210 nm were utilised. Estimated recoveries of acids added to silage ranged from 98.2 to 103.5%.
The effect of two harvests per year on the yield and composition of Tasmanian peppermint oil (Mentha piperita L.)
Authors: Clark Robert J. , Menary Robert C.
Published: October 2006

Peppermint (Mentha piperita L.) was harvested on two occasions during the growing season. Double harvesting yielded approximately 140 kg oil ha−‐1. The first harvest was timed to coincide with a period of maximum oil yield per unit area (ca. 70 kg ha−1) and yielded an oil containing 39% menthol. The oil yield in the subsequent regrowth increased to approximately 70 kg ha−1, and when harvested at this stage the oil contained high levels of methol (53%). The oils produced from the double harvest programme could either be combined to resemble the Tasmanian single harvest oil or marketed as distinctive oil types. Organoleptic evaluation indicated that oil from crops 1 and 2 resembled Midwest and Yakima Valley, USA, oils, respectively. Double harvesting had no apparent adverse effect on the regrowth in the following season.
Determination of the silicon content of food
Authors: Bowen H. J. M. , Peggs A.
Published: October 2006

The determination of silicon in biological material was investigated using solution absorption spectrometry (SAS) and atomic absorption spectrometry (AAS). Most analytical reagents and ion‐free waters contain enough silicon to cause high blanks, and require purification. Glassware and silica ware should not be used. Standard silica solutions do not polymerise in a week if the silicon concentration is below 100mg litre−1. Biological materials were dry‐ashed and then fused with pure sodium tetraborate before dissolution in dilute nitric acid. Phosphates interfere with SAS if the P:Si ratio exceeds 5:1 but can be removed by precipitation. They interfere somewhat less with AAS if the P:Si ratio exceeds 20:1. Borates, calcium, potassium and sodium do not interfere with AAS at ratios B:Si = 500:1, Ca:Si = 200:1, K:Si = 100:1, Na:Si = 1000:1. Determinations of silicon in foods by both methods agreed, and barley and oats were found to have a high silicon content. The average British diet is estimated to contain 31 mg silicon day−1.
Wine phenolics—analysis of low molecular weight components by high performance liquid chromatography
Authors: Salagoïty‐Auguste Marie‐Hélène , Bertrand Alain
Published: October 2006

Low molecular weight phenolic compounds were separated by high performance liquid chromatography on hydrocarbon‐bonded reverse phase packings, with a water‐methanol elution gradient. Phenolic compounds were extracted from wine with ethyl acetate. A first extraction at pH 7 enabled isolation of neutral molecules (catechins, procyanidins, flavonols, aromatic alcohols); a second extraction at pH 2 was performed to extract phenolic acids. Successive injections of these two extracts in the chromatograph gave the distribution of the different phenolic compounds in the wine under analysis. Analytical data are given for low molecular weight phenolic compounds present in young red Bordeaux wines from different vine cultivars.
A comparison of methods for estimating the cell‐wall content of forage
Authors: Moir Kenneth W. , Martin Peter R.
Published: October 2006

In a comparison of methods for estimating the cell‐wall content of forage, each of three methods was compared separately with the other two in regression analyses. Subtraction of unextracted protein from cell‐wall values removed differences in regression slopes. Parallel slopes, but different intercepts showed that different methods of extracting forage removed different amounts, rather than different proportions of non‐protein, cell‐wall material. With different extraction methods in use, cell‐wall values are meaningful among laboratories using identical analytical procedures, and then only if interference from unextracted protein is excluded.
Efficiency of dietary vegetable oils in preserving the quality of shell eggs under ambient tropical conditions
Authors: Obanu Zak A. , Mpieri A. A.
Published: October 2006

The study evaluates the efficacy of three common market‐grade culinary vegetable oils—groundnut oil, cottonseed oil and coconut oil—in preserving the internal quality of freshly laid eggs coated with them and stored under tropical room conditions of 25–32°C and 40–85% r.h. for 36 days. All three vegetable oils significantly (P<0.01) limited diurnal weight losses of the eggs to 0.013–0.016 g as against 0.186 ± 0.013 g for the untreated eggs over 36 days storage. Liquefaction of the yolk and albumen was also significantly reduced (P<0.05) such that the albumen pH of the oiled eggs increased from 7.65 to only 8.35–8.65 after 36 days when the untreated eggs had an albumen pH of 9.80. Subsequently, the yolk index of oiled eggs dropped by only 0.10–0.13 after 36 days and remained significantly superior (P<0.001) to that of the untreated eggs which had dropped from an initial value of 0.47 to 0.11. These preservative effects of the vegetable oils may be attributable to their fatty acid component, rather than their glycerol which showed no significant (P>0.05) improvement over untreated eggs.
Acceleration of autolysis during fish sauce fermentation by adding acid and reducing the salt content
Authors: Gildberg Asbjørn , Espejo‐Hermes Jasmin , Magno‐Orejana Florian
Published: October 2006

Good quality fish sauce was produced from anchovies (Stolephorus spp.) that had been allowed to autolyse at pH 4 and low salt concentration. After an initial phase of rapid autolysis, the samples were neutralised, and salt was added to the normal level (250 g kg−1) before the fish sauce was separated by suction. By this method fish sauce with acceptable flavour could be produced after 2 months, whereas the normal production time is more than 6 months. This rapidly‐produced fish sauce had a lower level of volatile base and acid, and a better balanced composition of essential amino acids than a first grade commercial fish sauce.
A simple method for the extraction of reducing and non‐reducing sugars from carrot and other storage root vegetables
Authors: McKee John M. T.
Published: October 2006

A procedure is described for the extraction of sucrose, glucose and fructose from storage root vegetables. An automatic domestic pressure cooker containing a circular test tube rack holding 36 tubes was used for the extraction. All water soluble sugars were extracted in 30 min at 110°C. The method is at least as efficient as those using hot ethanol and methanol: chloroform:water and is significantly more efficient in its use of time and energy.
Reduction of nitrate prior to kjeldahl digestion
Authors: Pruden Gordon , Kalembasa Stanislaw J. , Jenkinson David S.
Published: October 2006

A new method is described for reducing nitrate prior to Kjeldahl digestion of soil and crop samples. Zinc is used to reduce CrIII to CrII, which in turn reduces NO3—N. Zinc powder is mixed with the sample, a solution of CrK(SO4)2 in H2SO4 added and the mixture allowed to stand at room temperature for 2h. The usual Kjeldahl reagents (K2SO4, CuSO4 and H2SO4) are then added and the digestion completed in a digestion block at 360°C. Nitrate is quantitatively converted to NH4—N, whether on its own, in plant material or in soil.
Isoelectric focusing and sodium dodecylsulphate electrophoresis of buffer soluble seed proteins of twelve varieties of winged bean (Psophocarpus tetragonolobus L.)
Authors: Westermeier Reiner , Postel Wilhelm , Görg Angelika , Telek Lehel
Published: October 2006

Buffer‐soluble seed proteins of 12 varieties of winged bean (Psophocarpus tetragonolobus L.) were separated by ultrathin‐layer isoelectric focusing (IEF) and sodium dodecylsulphate electrophoresis(SDS‐PAGE). Whereas the molecular weight spectra of the proteins obtained by SDS‐PAGE were identical for all varieties studied, the IEF patterns showed variety specificity for each sample. Most of the variety specific protein bands were identified as glycoproteins. The zymograms of the isoelectically focused trypsin inhibitors were variety specific in both activity and isoelectric point distribution.
Effect of nitrogen fertilisation on protein content, total fatty acid content and composition of barley (Hordeum vulgare L.) grains
Authors: De Man Walter , Dondeyne Pieter
Published: October 2006

The impact of N‐fertilisation level on protein content, total fatty acid (TFA) content and major fatty acid composition of barley grains (cv. Eldorado), grown in a replicated field trial, was investigated. Increasing amounts of N‐fertiliser, applied at several stages during the growing season, resulted in a higher protein content and a very slightly lowered TFA content in the grains. Protein and TFA contents were negatively correlated (r=‐0.4685). Minor changes of fatty acid composition were found in the decrease of the oleic acid (C18:1) proportion (r=‐0.8376) and in the increase of the palmitic acid (C16:0) proportion (r=0.7273). The stearic acid (C18:0) and the linoleic acid (C18:2) proportions were also affected, however, no significant linear correlations with the total N‐fertiliser level were obtained. The slow increase in the linolenic acid (C18:3) proportion (r=0.5674) was too small, compared to the residual variance, to be significant. TFA content was positively (P<0.001) correlated with the oleic acid proportion, and negatively (P<0.001) with the palmitic acid proportion. These data suggest that the application of higher amounts of N‐fertiliser slightly decreases the total fatty acid content of barley grains, probably due to a decreased synthesis of oleic acid, precursor of the unsaturated C18 fatty acids. The result is a relative increase in palmitic acid.
Ultrasonic estimation of solid/liquid ratios in fats, oils and adipose tissue
Authors: Miles Christopher A. , Fursey Graham A. J. , Jones Richard C. D.
Published: October 2006

Data are presented for the speed of transmission of pulses of 2.5 MHz ultrasound through fats and oils at temperatures in the range −50 to +110°C. It is suggested that a measurement of the speed of ultrasound (V), which is greater in solid fats (Vs) than in oils (VL), might be used to provide an estimate of the proportion of solid in a partially solidified fat. An acoustic parameter ϕ is defined such that: magnified image and it is suggested that ϕ might be used as a practical index for determination of the volume fraction of solid fat. This procedure might be useful under conditions unsuited to the established methods of dilatometry, calorimetry or nuclear magnetic resonance. As an example of a possible application, measurements are presented for the speed of ultrasound in pig adipose tissues selected to show a range of consistencies which, by subjective assessment and by penetrometer measurements, ranged from ‘soft’, and therefore unsuited for the manufacture of bacon, to ‘hard’. After allowing for the contribution of the fat‐free tissue, it was estimated that the lipid in the tissues ranged from about 20 to 88% (by volume) solid. The variation in ϕ explained 88% of the variance in the penetrometer measurements.
Use of a scanning near‐infrared reflectance spectrophotometer for assessment of the malting potential of barley
Authors: Henry Robert J.
Published: October 2006

A scanning near‐infrared reflectance spectrophotometer was calibrated for the estimation of barley protein, moisture, total β‐glucan and predicted malt extract. About 50 samples covering the range normally encountered in selection in barley breeding were used for each calibration. The best prediction equations each using three wavelengths, gave the following root mean square differences for the samples used in the calibration; nitrogen, 0.042%; moisture, 0.22%; total β‐glucan, 0.26%; predicted malt extract, 1.4%. However, prediction of samples not in the calibration set was always slightly less accurate. These four characters were predicted in about 25 s allowing rapid screening for malting quality of large numbers of barley samples. The speed and simplicity with which successful calibrations could be produced suggests that the regular updating of calibrations to include barley from new seasons or regions should be possible.
The distribution of nutrient elements in cell wall and other fractions of the herbage of some grasses and legumes
Authors: Whitehead David C. , Goulden Katherine M. , Hartley Roy D.
Published: October 2006

The distribution of 10 nutrient elements was assessed in three fractions of herbage samples of perennial ryegrass, tall fescue, white clover and lucerne. The cell wall fraction, prepared by mechanical disintegration of undried material, contained the following proportions of the total herbage content of the major elements: N, 2.9–16.4%; P, 3.0–6.9%; S, 3.6–17.2%; Ca, 11.3–51.8%; Mg. 6.4–27.6% and K, 0.1–1.7%. Substantial though more variable proportions of the trace element cations, Fe, Mn, Zn and Cu were also present in the cell wall fraction. The extent to which the elements were soluble in water was assessed by analysis of the water‐insoluble fraction prepared from freeze‐dried samples of each herbage. The proportions of the total herbage content of the major elements soluble in water were: N, 30–57%; P, 80–92%; S, 35–71%; Ca, 48–69%; Mg. 65–83% and K, 90–96%. With the trace element cations the proportions soluble in water were more variable, though they were generally less than 70% of the total. The extent to which the various elements were soluble in 80% aqueous ethanol was assessed by analysis of the insoluble fraction prepared from freeze‐dried materials. With each of the major elements, smaller proportions of the total herbage content were soluble in 80% ethanol than in water, which may reflect in part the lower solubility of proteins and pectin. With the trace element cations, the differences in solubility between 80% ethanol and water were generally small and inconsistent.
Redistribution of minerals in apple fruit during storage: Effects of late summer pruning, calcium sprays and low temperature breakdown
Authors: Perring Michael A.
Published: October 2006

Transverse distribution patterns of calcium, magnesium and phosphorus in Cox's Orange Pippin apples at harvest and subsequent redistribution patterns during storage in air at 0°C were measured. Distribution and redistribution patterns differed from those in Spartan apples measured in the previous year. Orchard calcium sprays increased the proportion of calcium in the outer parts and slightly increased the proportion of magnesium towards the centre of the fruit. Late summer pruning slightly increased the proportion of magnesium in the core at harvest and increased the rate of redistribution of calcium from the core to the outer fruit parts during storage. Redistribution patterns, especially those of magnesium, were drastically altered when low temperature breakdown developed and minerals moved into the affected zones.