bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical Composition of Oat Seed Epicuticular Wax
Authors: Moyna Patrick , Garcia Manuel
Published: October 2006

The analysis of the main components present in Avena sativa seed epicuticular wax is reported, using a simplified chemical procedure. The main components are esters (21.1%), hydrocarbons (15.5%) and free acids (14.1%).
Effect of extracts from bean (phaseolus vulgaris) and field bean (vicia faba) varieties on intestinal D‐glucose transport in rat in vivo
Authors: Motilva María J. , Martínez José A. , Ilundain Anunciación , Larralde Jesús
Published: October 2006

Saline extract solutions from seeds of both Phaseolus vulgaris and Vicia faba varieties were prepared and tested for their total polyphenolic content and effect on intestinal D‐Glucose transport across rat ileum in vivo. Intestinal D‐glucose transport was significantly reduced (P < 0.001) by the presence of seed‐extracts in the intestinal loop, regardless of the source of the extract. The order of potency (Phaseolus vulgaris, var. artropurpurea > Vicia faba, var. caballar > Vicia faba, var. minor > Phaseolus vulgaris, var. albus) is closely related to the polyphenolic content. Clear differences in the mode of action of the extracts were also observed. Extracts with appreciable polyphenolic content caused both a reversible and a lasting inhibitory effect on glucose transport, whilst extracts with negligible polyphenolic content only induced a reversible inhibition. Polyamide treatment of the extracts decreased their ability to inhibit glucose transport, but their inhibitory effect was not completely abolished by the treatment, further suggesting the presence of some other anti‐absorptive factor(s) in the seeds.
The isolation and purification of indole glucosinolates from brassica species
Authors: Truscott Roger J. W. , Minchinton Ian , Sang Joseph
Published: October 2006

A method for the purification of indole glucosinolates from cruciferous plants using ion‐exchange chromatography on DEAE‐Sephadex A‐25 is described. The procedure is suitable for the isolation of indole glucosinolates from both seed and leaf tissue. Using this preparative technique a fraction containing intact indole glucosinolates is obtained which can be used for subsequent purification of the individual components. Alternatively, the indole glucosinolates can be desulphated on‐column, and the resulting desulpho‐derivatives purified in high yield by high‐performance liquid chromatography.
The synthesis and absorption of pantothenic acid in the gastrointestinal tract of the adult sheep
Authors: Finlayson Heather J. , Seeley Robert C.
Published: October 2006

A microbiological assay using Lactobacillus plantarum was used to determine the levels of pantothenic acid (PA) in food and digesta samples from sheep fitted with duodenal and ileal re‐entrant cannulas, given a variety of diets. ACP‐bound PA was not measured. With most of the diets studied there was an increase in ‘total’ PA and CoA‐bound PA before the small intestine. Both the increase in CoA‐bound PA prior to the duodenum and the ‘total’ PA reaching the duodenum were positively and significantly related to the microbial dry matter synthesised in the rumen. Free PA at the duodenum was significantly related to the dietary intake of free PA. The apparrent absorption of total PA within the small intestine was significantly related to the quantity entering the small intestine suggesting a passive absorption mechanism. It is suggested that CoA‐bound PA entering the small intestine is hydrolysed to release free PA which is then available for absorption.
Enzymic saccharification of wheat straw—differences in the degradability of straw derived from different cultivars of winter wheat
Authors: Knapp Jeremy S. , Parton John H. , Walton Neil I.
Published: October 2006

Saccharification of ball‐milled winter wheat by an enzyme preparation from Trichoderma reesei containing both cellulase and xylanase activities has been investigated. Straw from different cultivars of winter wheat differed in the amount of reducing sugars released by the enzymes and by the buffer alone. Although only seven cultivars were tested, differences in degradability of as much as 22% were recorded. Differences of this magnitude are likely to be of economic significance when considering the recycling of cereal straws. It is therefore important that account is taken of the cultivar of cereal straw to be used.
Assessment of nitrogen status of soils for cereal crops: Effects of nitrogen fertiliser on growth, composition and yield of spring barley
Authors: O'Neill Eileen J. , Batey Thomas , Cresser Malcolm S.
Published: October 2006

The effects of fertiliser N on the growth rate and nitrogen and pigment concentrations of spring barley throughout growth were measured at two locations in north‐east Scotland in consecutive years. Inorganic N in soil was also measured as were grain and straw yields at maturity. The results show that plant analysis, as early as 3 or 4 weeks after emergence of barley, was an effective assessment of soil N status.
Effects of acidity, calcium, and aluminium on fish survival and productivity—a review
Authors: Howells Gwyneth D. , Brown David J. A. , Sadler Keith
Published: October 2006

Fish survival, growth and productivity are dependent on both biological and environmental factors. The latter can be distinguished as edaphic (which includes water quality) and morphometric (which includes lake and stream morphology). Climatic factors are relatively less significant in temperate waters, except over a long time scale, or over wide geographic areas. In the conditions characteristic of acid lakes— low pH, low calcium and high aluminium concentrations—survival may be reduced, growth may be affected and, consequently, productivity will be low. In spite of inconsistencies in the literature, it can be shown that at low pH (⋍ 4.5), a limiting concentration of calcium is about 1 mg litre−1 and aluminium can have adverse effects at 250 μg litre−1 within a limited range of pH. These three factors appear to interact. Taking age specific fecundity of adults and survival of eggs and fry, it is possible to predict the limiting conditions for maintenance, growth or decline of a fish population. At pH 4.5 and calcium < 0.8 mg litre−1 it may be expected that many lakes will be fishless.
Specific factors affecting lead uptake by food from cooking water
Authors: Smart Gloria A. , Warrington Marjorie , Dellar Dorothy , Sherlock John C.
Published: October 2006

Following earlier work, detailed studies have been carried out on the lead uptake of individual foods from soft and hard water containing various amounts of lead. Experiments have also been made to determine whether solutions of lead nitrate in distilled water simulate the behaviour of water containing naturally present lead. The effect of length of cooking time, weight/volume ratio and salt addition have been studied, as well as the depostion of lead on to cooking vessels. In general, green vegetables, carrots, rice and spaghetti were found to take up more lead than do other foods. The difference in uptake observed between hard and soft waters varied according to the particular food being studied. Uptake from lead nitrate solutions showed a very similar pattern to uptake from hard water containing naturally present lead. Equilibrium was reached after only 5 min cooking for cabbage and spaghetti. Varying the solid/volume ratio for cabbage affected the uptake of lead from water, but the addition of sodium chloride or sodium bicarbonate had little effect on lead uptake. There was no sign of saturation in uptake of lead by cabbage from solutions of 11 mg litre−1 lead as lead nitrate. Deposition of lead occurred on both aluminium and glass saucepans, and cleaning was more effective in removing lead from glass saucepans. Results obtained from the analysis of diets in a small population at Ayr confirmed those obtained previously by laboratory experiments.
Drying wheat with solid heat transfer medium
Authors: Mittal G. S. , Lapp H. M. , Townsend J. S.
Published: October 2006

Laboratory experiments have shown the feasibility of drying milling wheat from 17.0 to 14.5% moisture content using hot sand. The amount of moisture removed increased with the increase in residence time from 1 to 2 min but decreased when the residence time was increased to 3 min. Heated sand to wheat mass ratios ranging between 3:1 and 5:1 were found to be effective in removing moisture from wheat with sand temperatures ranging from 90 to 105°C.
Nutritive value of raw, parboiled, stabilised and deoiled rice bran for growing chicks
Authors: Zombade Shivaji S. , Ichhponani Jagmohan S.
Published: October 2006

The proximate analysis of different types of rice bran (raw, parboiled, stabilised and deoiled) showed wide differences in the oil, fibre, ash and available carbohydrate contents. Free fatty acids in the fat extracted from the raw, parboiled and stabilised rice brans were 500.6, 277.8 and 163.1 g kg−1 respectively. Palmitic, oleic and linoleic acids constituted about 94.5% of the total fatty acids in oils extracted from those rice bran types.

In chick growth trials, the average metabolisable energy of raw, parboiled, stabilised and deoiled rice brans was found to be 12.34, 11.67, 12.11 and 9.08 MJ kg−1 DM, respectively. The bodyweight gain of broiler chicks over a period of 6 weeks was depressed by 183, 79, 49 and 200 g when the level of the respective brans was raised from 200 to 400 g kg−1 in the diet. However, the food and protein conversions were significantly depressed at both levels of rice bran in the diets.
Protein extraction from pasture: Effect of crop species and of a reducing agent on the quality of extracted protein
Authors: Donnelly Paul E. , McDonald Rod M. , Rattray Peter V.
Published: October 2006

Leaf protein concentrations (LPC) were prepared from herbage harvested from pure stands of ryegrass (Lolium perenne), white clover (Trifolium repeens), lucerne (Medicago sativa cv. Wairau) and from a stand of ryegrass/white clover dominant pasture: each crop was processed with and without the addition of sodium metabisulphite just prior to pulping. Protein quality was measured by rat growth and in‐vivo rat true digestibility. Juice protein composition was measured and was related to chemically available lysine and protein true digestibility. Protein in ryegrass LPC had a lower digestibility (72%) than that from white clover (81%) or lucerne (78%), due to a higher proportion of the juice true protein being from the chloroplastic fraction for ryegrass (73%) compared with the two legumes (49–56%). The chloroplastic fraction is of inherently lower digestibility than the cytoplasmic fraction. Metabisulphite treatment at pulping caused a small but consistent increase of chemically available lysine in the LPC, and also improved chemically available methionine and protein utilisation for growth. Effects on protein true digestibility were inconsistent. When LPC was fed with a methionine supplement, the efficiency of utilisation of protein for growth did not differ amongst the four crops. This occurred despite the true digestibility of protein on LPC being higher for the legumes than for ryegrass and ryegrass/white clover.
Some flavouring constituents of cassava and of processed cassava products
Authors: Dougan James , Robinson Janet M. , Sumar Salim , Howard George E. , Coursey D. G.
Published: October 2006

Flavouring constituents of cassava, gari and farine were analysed and compared. The characteristic compounds of gari were identified as pyrazines and lactic acid. Farine, which is either unfermented or fermented for a much shorter time than gari, was qualitatively similar but had fewer volatiles, present in small amounts. Pyrazines and lactic acid were absent from cassava, the flavouring constituents of which were fewer and qualitatively different from those of gari and farine. The characteristic flavour of gari and farine was largely due to the fermentation and roasting processes.
The determination of endogenous urinary nitrogen in protein quality studies with rats
Authors: Eyre Michael D.
Published: October 2006

The determination of the endogenous urinary nitrogen (EUN) excretion in protein quality studies using the Thomas‐Mitchell method with rats has usually been estimated using either a protein‐free or low concentration egg protein diet. Generally no effort has been made to equate EUN excretion with the urinary nitrogen excretion in the urine whilst the rat is in a state of maintenance. An attempt was made to find the diet which would maintain the weight of the rats used to determine the EUN at the time of the balance period of the protein quality test animals. It was found that a diet containing 20 g egg albumen kg−1 came the nearest to fulfilling this criterion and was the diet most suitable for the determination of the EUN.
Changes in the content and composition of vitamin E in damp barley stored in airtight bins
Authors: Hakkarainen R. V. Juhani , Työppönen Jouko T. , Bengtsson S. Gösta
Published: October 2006

The effect of airtight storage on the content and composition of vitamin E was studied in damp barley at 20 and 28% moisture. Airtight storage with an external supply of carbon dioxide was compared with conventional airtight storage with or without an expansion sack. In two additional models, the grain was also treated with 1% ammonia (NH3). The tocopherols and tocotrienols in the grain were analysed using high pressure liquid chromatography with fluorescence detection. The changes in vitamin E during airtight storage were determined by the moisture content of the barley. In barley at 20% moisture, the vitamin E content increased until mid‐April and after 10 months the final levels were similar to those at harvest (55–65 mg kg−1) except in the bin treated wih ammonia. In barley at 28% moisture, vitamin E breakdown processes prevailed from the beginning of airtight storage and led to an unsatisfactory level of this vitamin in the grain. In barley, α‐tocotrienol was clearly the dominating isomer. The relative distribution of the isomers in barley at 20% moisture was stable during the airtight storage. For 28% moisture barley in most of the experimental models, the fraction of tocopherol isomers increased at the cost of the tocotrienols. It was concluded that the higher moisture content and a lower pH apparently favoured saturation of the side chains of the trienols. Treatment of barley with 1% ammonia gas resulted in a general decrease in the total vitamin E content and a simultaneous increase in the relative fraction of α‐tocotrienol. Therefore, α‐tocotrienol appeared to be more resistant to ammonia treatment than are the other isomers. For barley at 20% moisture content, the type of silo arrangement had hardly any effect on the vitamin E concentration or on the proportions of the isomers. For the barley at 28% moisture content, an external supply of CO2 appeared to have a preservative effect on vitamin E content.
Observations on nitrile production during autolysis of kale and swedes, and their stability during incubation with rumen fluid
Authors: Forss David A. , Barry Thomas N.
Published: October 2006

A method was modified for quantitatively measuring total nitriles produced from glucosinolate degradation during autolysis of kale and swede plant tissue. Nitrile production from New Zealand Medium Stem kale was less at pH 7.5 (0.28 mol mol−1 glucosinolate) than at pH 5.7 (0.57 mol mol−1 glucosinolate). Lower levels were produced from Maris Kestrel kale, due both to a lower glucosinolate content and to reduced conversion of glucosinolate to nitriles. The amount of nitrile obtained on conversion of glucosinolate tended to be reduced by growing New Zealand Medium Stem kale in soil of low SO4‐S concentration, due to a reduction in plant glucosinolate content. Nitrile production from swede tissue was 0.3–0.5 mol mol−1 glucosinolate. Nitriles produced from swedes were rapidly degraded upon incubation with rumen fluid (4 h), whereas nitriles produced from kale remained stable for incubation periods up to 23 h. The high rate of conversion of glucosinolate to nitriles coupled with their stability in rumen fluid suggests that, in addition to goitrogenic properties, nitrile formation also deserves attention in the nutrition of ruminant animals fed kale diets. Of the four brassica diets tested, New Zealand Medium Stem kale is considered the most likely to cause nutritional problems (depressions in intake and reproduction) from nitrile production, and a method of testing this is suggested.
Some biochemical changes associated with post‐harvest storage of white yam (Dioscorea rotundata) tubers
Authors: Ikediobi C. O. , Oti E.
Published: October 2006

Healthy Dioscorea rotundata tubers were kept for 8 months under local storage conditions and periodically analysed for the activity of some enzymes of carbohydrate metabolism as well as for the concentrations of key tuber metabolites. Except for polyphenol oxidase, all the other enzymes monitored showed low and maximum activities before and at onset of sprouting, respectively. The activities of these enzymes after sprouting remained higher than those in the pre‐sprouting period. Hexokinase, alcohol dehydrogenase and phosphorylase showed an approximately 2‐fold increase in activity at sprouting while glucose‐6‐phosphate dehydrogenase showed a more than 3‐fold increase in activity. Polyphenol oxidase (PPO) activity and starch content decreased steadily with storage with PPO activity decreasing to one‐half by the end of storage. L‐ascorbate, total polyphenols, carotenoids and lipids increased with storage and peaked at sprouting.
A micro‐method for the estimation of oil content and fatty acid composition in seeds with special reference to cyclopropenoic acids
Authors: Gaydou Emile M. , Rasoarahona Jean , Bianchini Jean‐Pierre
Published: October 2006

A micro‐method is described for the routine estimation of oil content and fatty acid composition in seeds containing cyclopropenoic fatty acids (CPEFA) by determination of the total and component long‐chain fatty acids. The oil was transmethylated without prior extraction using 1.17% sodium methoxide in methanol at 80°C for 45 min. The resultant fatty acid methyl esters were separated and measured by gas‐liquid chromatography using a glass capillary column coated with Carbowax 20 M at 170°C. The method was shown to be applicable to a wide range of seeds including cottonseed (Gossypium hirsutum), kapok (Ceiba pentandra), paka (Urena lobata), baobab (Adansonia grandidieri and A. suarezensis). Individual seeds can be used with this method which needs only 50 to 150 mg for analysis. Results obtained with this micro‐method were reproducible and good recoveries of oil and individual fatty acids were observed. The micro‐method was compared for the determination of CPEFA (malvalic plus sterculic acids) to the nuclear magnetic resonance quantitation and gas‐liquid chromography after derivatisation of CPEFA in more stable compounds.
Nutrient composition of taro (Colocasia esculenta) cultivars from the Papua New Guinea highlands
Authors: Wills Ron B. H. , Lim Jessie S. K. , Greenfield Heather , Bayliss‐Smith Tim
Published: October 2006

Taro samples were analysed for water, protein, fat, fructose, glucose, sucrose, maltose, starch, organic acids, dietary fibre, ash, sodium, potassium, iron, calcium, magnesium and zinc and the energy content was calculated. The composition of ‘Yaguat’ taro was determined at various intervals during growth. The most marked changes were in immature corms with a decrease in water content and an increase in starch and energy content. There were minimal changes in composition of taro from slightly immature to over‐mature stages. The composition of 36 samples of mature taro from 22 cultivars grown in four districts was determined. There was a large range in proximate composition between cultivars for most nutrients; for example, water ranged from 55.8 to 74.4 g 100 g−1, starch 20.0 to 35.1 g 100 g−1 protein 0.5 to 2.1 g 100 g−1, dietary fibre 1.4 to 5.4 g 100 g−1 and energy 403 to 672 kJ 100 g−1. However the same cultivar grown in two districts tended to have a similar composition. Mineral levels were variable between samples but the greatest variation was with zinc which varied widely between districts.
Pyrolysis‐mass spectrometry of the phenolic constituents of plant cell walls
Authors: Hartley Roy D. , Haverkamp Johan
Published: October 2006

Cell walls of plant parts of maize, barley, Italian ryegrass, wheat bran, lucerne and red clover were subjected to low voltage pyrolysis‐mass spectrometry. The ion intensity at m/z 120, which is characteristic of p‐coumaric acid, was significantly correlated (r=0.99) with the p‐coumaric acid content of the walls; the ion intensity at m/z 150, characteristic of ferulic acid, was present in the spectra of the graminaceous walls. Factor analysis of the pyrolysis‐mass spectra indicated that some, at least, of the p‐coumaric and ferulic acid constituents of the walls are bound to pentosans, and suggested that not all the aromatic constituents of the walls are bound to polysaccharides.
Ethylamine content of fresh tea shoots and made tea determined by high performance liquid chromatography
Authors: Tsushida Tojiro , Takeo Tadakazu
Published: October 2006

The ethylamine contents of tea shoots and made teas were derived with o‐phthalaldehyde and 2‐mercaptoethanol, and quantified by high performance liquid chromatography. The coefficient of variation of this method was 1.97% from eight analyses.

The levels of ethylamine in tea shoots declined markedly during growth and senescence after plucking; they also declined in the extracts of fresh tea during the incubation at 37°C, but this decrease was completely inhibited by amine oxidase inhibitors.

The content of ethylamine in high grade green teas was higher than in low grade teas, but was almost identical in high and low grade black tea. The mean contents of ethylamine in 22 green teas and 17 black teas were 6.76±3.07 μmol g−1 and 6.40±1.82 μmol g−1, respectively.
Effect of the withering process on volatile compound formation during black tea manufacture
Authors: Takeo Tadakazu
Published: October 2006

The amount and composition of volatile compounds in the volatile oils were compared between non‐withered tea and withered tea.

Important differences in the aroma constituents were found in the amounts of E‐2‐hexenal, Z‐3‐hexanol ester, linalool and its oxides, and methylsalcylate. In withered teas, the amounts of Z‐3‐hexenol ester, linalool and its oxides, and methylsalcylate were much greater than in non‐withered tea, but the E‐2‐hexenal content was higher in non‐withered tea.

From the results it was thought that the withering process has an important role in the formation of volatile compounds in tea shoots during black tea fermentation.
Application of near infrared reflectance spectroscopy to the compositional analysis of biscuits and biscuit doughs
Authors: Osborne Brian G. , Fearn Thomas , Miller Andrew R. , Douglas Stuart
Published: October 2006

The possible use of near infrared (n.i.r.) diffuse reflectance spectroscopy in the monitoring of automatic metering equipment used for fat, sucrose, dry flour and water in short dough biscuit production has been investigated. The experimental design involved randomisation of a standard pilot scale Lincoln biscuit recipe to produce calibration and prediction samples and comparison of n.i.r. results with the levels of ingredients determined from the recipe. The use of several strategies based on regression analysis for selection of the ‘best’ wavelengths for reflectance measurements for each analyte was investigated. A novel strategy based on computing the regressions on analyte concentration of all possible pairs of reflectance readings across the spectrum at given intervals is presented.

The results of the experiments demonstrate that the precision of the n.i.r. method is excellent for all four constituents, but only the calibrations for fat are sufficiently accurate to be capable of detection of metering errors of ±5% relative to the total amount of fat in the recipe.
Effects of time of season, fruit depth and covering at night when ground drying, on acceptable moisture content of sultana raisins
Authors: Clingeleffer Peter R.
Published: October 2006

A number of factors involved in the ground drying of sultana raisins to give an acceptable moisture content (‘finishing off’) were studied. Drying responses were related to the potential for water movement from the fruit to the surrounding air as determined by vapour pressure differentials. The direct input of solar radiation energy during the day raises berry temperatures and increases the vapour pressure differential, thus drying occurs. The results show that drying is unduly retarded and non‐uniform when fruit is spread in layers exceeding 25 mm that is, a depth of 3–4 berries. Covering the fruit at night to protect from dew is unnecessary, as the moisture uptake by berries at night is very slow because at the lower temperatures the potential for water movement into the berries is small, and the dew on the surface evaporates once solar radiation increases in the morning. As the season progressed from March to May, conditions for drying became less favourable as both the intensity of the solar radiation and daylength decreased, thus reducing both berry temperatures and the length of drying time per day. These changes were reflected in the measured drying rates.
The effect of pod and seed positions on the physical and cooking properties of faba beans (Vicia faba)
Authors: Ziena Hamid M. , El Shehata Ahmed M. ‐Tabey , Youssef Mohammed M.
Published: October 2006

The effect of pod location on plant (lower, middle and upper regions) and seed position inside the pods (nodular, middle and terminal) on certain characteristics of dry and stewed faba beans were studied. The weight, volume, relative density, seed coat (%), hydration and swelling coefficients were determined for dry seeds. Hydration and swelling coefficients, fractured beans (%), penetrometer readings and scores of colour, granulation and softness (by taste panel) were evaluated for stewed beans. The weight, volume, relative density, pH, and total and soluble solids content of the stewed liquor were also measured. Analysis of variance showed that the weight and volume of 1000 dry seeds were significantly (P<0.001) affected by pod location and seed position. Higher values were obtained for lower pods and terminal and middle seeds. Seeds from upper pods had the highest percentage of seed coat. Pod location showed a significant effect on the weight, volume, pH, soluble and insoluble solids of stewed liquor. No significant effect was found for pod location or seed positions on the characteristics of stewed beans, except the hydration coefficient which was significantly affected by pod location.
Lead and arsenic levels in wines produced from vineyards where lead arsenate sprays are used for caterpillar control
Authors: Handson Peter D.
Published: October 2006

Twenty‐seven dry table wines from 14 wineries throughout Victoria were analysed for lead and arsenic. Wines originating from vineyards using lead arsenate insecticide for caterpillar control had mean levels of 0.31 mg litre−‐1 lead and 0.08 mg litre−‐1 arsenic. The mean levels in similar wines from wineries not using lead arsenate sprays were 0.03 mg litre−‐1 and less than 0.01 mg litre−‐1 respectively.
Preservation of tomato juice under acid conditions
Authors: Sidhu Jiwan S. , Bhumbla Virendra K. , Joshi Bhuwan C.
Published: October 2006

A technique for preserving tomato juice and crushed tomatoes under acid conditions has been developed. This eliminates the need for the usual processing time of 55 min in boiling water for 650 ml glass bottles, which would result in considerable savings in energy requirements by the tomato processing industry. The ketchup prepared from the acidified tomato juice and crushed tomatoes (after neutralisation) was rated by the panelists to be as good as a commercial tomato ketchup sample.
The production of ochratoxin A and citrinin in barley
Authors: Damoglou Anthony P. , Downey Gerard A. , Shannon Wesley
Published: October 2006

The production of ochratoxin A by Aspergillus ochraceus and of ochratoxin A and citrinin by Penicillium viridicatum growing on previously sterilised barley for 200 days at 5, 10 and 20°C and a water activity of 0.85 is reported. A. ochraceus did not grow at 5°C, multiplied slowly at 10°C but did not produce toxin. At 20°C the organism multiplied more quickly and produced ochratoxin after 19 days, which slowly disappeared over the next 150 days. P. viridicatum grew slowly at 5°C but did not produce any toxin. It multiplied at 10°C and produced ochratoxin A which was only detectable during the period from 100 to 150 days. At 20°C both ochratoxin A and citrinin were produced. Ochratoxin A was detected after 10 days and was still present after 240 days, whereas citrinin was produced in large quantities between 118 and 129 days and then rapidly disappeared.
The nature of the oxygenated fatty acids present in Malva parviflora seed oil
Authors: Ahmad Moghis U. , Sinha Sarita , Husain Syed K. , Osman Sheikh M.
Published: October 2006

The seed oil of Malva parviflora L. (Malvaceae) is known to contain glycerides of cyclopropene (malvalic and sterculic), cyclopropane (dihydromalvalic and dihydrosterculic), epoxy, and conjugated dienol acids. By preparative thin layer chromatography, the epoxy and conjugated dienol acids were isolated as their methyl esters. These were characterised as cis‐12, 13‐epoxy‐cis‐9‐octadecenoic (vernolic) acid, and 13‐hydroxy‐cis‐9, trans‐11‐octadecadienoic (coriolic) acid.
The levels of S‐alk(en)yl‐L‐cysteine sulphoxides during the growth of the onion (Allium cepa l.)
Authors: Lancaster Jane E. , McCallion Barbara J. , Shaw Martin L.
Published: October 2006

Flavour precursors, the S‐alk(en)yl‐L‐cysteine sulphoxides, change considerably in both concentration and total amount during the growth of onions. For the brown onion cv. Pukekohe Long Keeper (PLK) and for the white onion cv. Dehyso, (±)‐S‐1‐propyl‐L‐cysteine sulphoxide (±PCSO) is the predominant flavour precursor, with (±)‐trans‐S‐1‐propenyl‐L‐cysteine sulphoxide (±PECSO) and (±)‐S‐1‐methyl‐L‐cysteine sulphoxide (±MCSO) in a minor role. For PLK the greatest concentration of all three precursors is just prior to bulbing (3.6±1.1 mg g−1 fresh weight); for Dehyso the greatest concentration is at bulbing (4.6±0.6 mg g−1 fresh weight); Both varieties show a mid‐season reduction in flavour precursor concentration (of about 45%), followed by a small but significant increase in ±PCSO concentration during the end of season leaf die‐down. The total amount of the three flavour precursors per bulb in both varieties shows a maximum in late January (360±107 mg for PLK, 602±144 mg for Dehyso). In the subsequent months there is a dramatic reduction in the total amount of ±PECSO and ±MCSO, and a slight reduction in ±PCSO. Both varieties show an increase in the amount of ±PCSO at leaf die‐down. The relative proportions of these flavour precursors change with bulb age and cultivar. These results suggest that white onions used for drying and processing could be harvested from bulbing onwards. Furthermore, when onion cultivars and onion plant selections are assessed for flavour, care needs to be given to the stage of maturity of the onion.
Amino and organic acids of the prickly pear cactus (Opuntia ficus indica L.)
Authors: Teles F. F. Feitosa , Stull J. Warren , Brown William H. , Whiting Frank M.
Published: October 2006

The amino acids of prickly pear (Opuntia ficus indica L.) proteins, free amino acids and nonvolatile organic acids were determined on fresh and lyophilised young pads. The calculated biological value of prickly pear protein was 72.6, relative to egg protein. Trace amounts of malonic, malic and citric acids in material collected at 1800 hours; traces 0.95 and 0.31 mg g−1, respectively. In similar material analysed at 0600 hours, the concentrations of those acids were 0.36, 9.85, and 1.78 mg g−1, respectively. Since there was a significant accumulation of the acids during the evening, crassulacean‐type metabolism is suggested.
Degradation rate and chemical composition of different types of alkali‐treated straws during rumen digestion
Authors: Lindberg J. Eric , Ternrud Ingrid E. , Theander Olof
Published: October 2006

The degradation in the rumen and change in chemical composition of untreated and four samples of alkali‐treated barley straw were studied in farm‐scale treatments with ammonia, ‘dry’ sodium hydroxide and two different aqueous sodium hydroxide systems. The alkali treatments increased the fraction soluble in organic solvents and decreased the lignin content (determined as Klason lignin). The amounts of cellulose and arabinoxylans were not significantly changed. The degree of rumen degradability increased with the order of alkaline treatment given above. The degradation rates of dry matter and the NDF fraction were parallel to each other but varied considerably with the treatments. The two most efficient aqueous alkaline treatments showed a degradation rate four times that of untreated straw. For these two samples the arabinoxylans were solubilised faster than cellulose during the first part of the incubation. In the other samples the degradation of arabinoxylans and cellulose ran almost parallel. During the rumen incubation the lignin content of the straw residues increased for all samples. There was an inverse relationship between the content of p‐coumaric and ferulic acids on the degree of digestibility. A relationship between acetyl groups and digestibility was not found.
Effects of tal pro‐long, a surface coating agent, on the shelf life and quality attributes of plantain
Authors: Olorunda Ayodele O. , Aworh Ogugua C.
Published: October 2006

The effects of Tal Pro‐long, a commercial fruit coating, on the shelf life and selected quality attributes of plantain were investigated. Relative to untreated fruits, yellow colour development was retarded by 4 to 8 days, and changes in pH and total acidity were delayed in plantain dipped in 1.5% or 2.5% Pro‐long solution when stored at 30°C or at 20–24°C. Pro‐long treatment had less effect on the pulp: peel ratio of plantain and on changes in moisture contents of pulp and peel during storage. After ripening, fruits dipped in 1.5% Pro‐long solution produced an acceptable, though slightly inferior, fried plantain product relative to untreated fruits.
The use of hydrogen peroxide for the digestion and determination of total nitrogen in chickpea (Cicer arietinum L.) and pigeonpea (Cajanus cajan L.)
Authors: Singh Umaid , Sahrawat Kanwar L. , Jambunathan Ramamurthi , Burford John R.
Published: October 2006

The use of hydrogen peroxide as an alternative to catalysts in the determination of nitrogen in plant materials has been investigated. Nitrogen determination in leaf, stem and seed samples of chickpea and pigeonpea was carried out by three digestion procedures, using hydrogen peroxide (H2O2 digestion) without a catalyst, and with mercury or selenium as catalysts (catalyst digestions). The nitrogen values obtained by the three digestion procedures did not differ significantly from each other when examined by microKjeldahl (MKJ) using mercury as a catalyst, and by a Technicon auto analyser (TAA) using selenium as catalyst. The gradual addition of H2O2, as recommended previously, was found to be unnecessary. In view of the cost and health hazards implicated with the use of mercury and selenium for digestion, the procedure based on H2O2 digestion is preferable for large scale N determinations in plant tissue and seed samples of these pulse crops. The results sugest that the H2O2 digestion technique can be conveniently adapted for total N analysis in plant tissues and grain samples by either TAA or MKJ method.
Effect of cardiac arrest on susceptibility to carcass bruising in sheep
Authors: Gregory Neville G. , Wilkins Lindsay J.
Published: October 2006

The effect of inducing a cardiac arrest at electrical stunning on the susceptibility of the carcass to bruising was evaluated in thiopentone‐anaesthetised sheep. Bruising was induced with a percussion pistol and measured in terms of meat appearance and extractable haem pigment. Cardiac arrest caused a prompt and marked reduction in susceptibility to bruising, and it is concluded that stunning techniques which cause simultaneous heart failure could help to reduce the incidence of carcass bruising. Exsanguination of sheep which had a normal cardiac rhythm prevented the induction of bruising once 50% of the total blood loss had occurred.
Natural plant enzyme inhibitors. Studies on a proteinase inhibitor from Italian millet (Setaria italica)
Authors: Udupa Saraswati , Pattabiraman Thillaisthanam N.
Published: October 2006

A proteinase inhibitor specific for trypsin was purified from Italian millet (Setaria italica) 170‐fold by extraction with 0.02M HC1, ammonium sulphate fractionation, chromatography on CM‐cellulose and trypsin‐affigel chromatography. The inhibitor with an Mr of 14000 was found to be homogeneous by gel chromatography on Sephadex G‐100 and sodium dodecyl sulphate‐polyacrylamide gel electrophoresis. It reacted with bovine trypsin in a 1:1 stoichiometric fashion. Inhibition of trypsin was nearly double when assayed with benzoyl DL‐arginine p‐nitroanilide as substrate compared to the activity with casein as substrate. The inhibitor affected the tryptic activity in human and bovine pancreatic preparations to an equal extent. Chemical modification studies showed that amino groups, disulphide bridges and sulphydryl groups are essential for the action of the inhibitor. Pretreatment with porcine pepsin or bovine α‐chymotrypsin increased the antitryptic activity of the inhibitor when assayed with the low molecular weight substrate but not with casein.
Compositional changes and biosynthesis of lipids in the developing kernels of almond (Prunus amygdalus batsch)
Authors: Munshi Satish K. , Sukhija Pritam S.
Published: October 2006

Fruit and kernel weights of developing almond kernels increased with age. The kernel contents had a translucent and jelly‐like appearance in the initial developmental stages, but solidified prior to the accumulation of dry matter, mainly oil, from 50 days after fertilisation (DAF). During kernel development the oil content displayed a double sigmoid pattern. Oleic and linoleic acids accumulated to similar levels, but the linolenic acid content decreased during development. Oil‐filling ([1‐14C]acetate incorporation) commenced at 50 DAF, and reached a maximum level at 70 DAF. The total polar lipid content was highest at 10 DAF, as determined by radioactive labelling, but from 30 DAF onwards a de‐novo synthesis was noted. Diphosphatidyl glycerol (Cardiolipin) acted as a temporary reservoir for the synthesis of phospholipids from 70 DAF, and thereafter the synthesis of phosphatidyl choline was enhanced. In the initial stages, the rate of synthesis of monogalactosyl diglycerides was greater than that of digalactosyl diglycerides, and a de‐novo synthesis of both was observed from 30 DAF. The synthesis of triacylglycerols corresponded well with the pattern of oil‐filling. The level of 14C radioactivity recorded in sterol esters was greater at the initial stages, but declined from 50 DAF, possibly because of the effect of dilution, as envisaged in the case of the triacylglycerols.
Contributions to the cadmium, lead and mercury contents of diets by using grinding stones
Authors: Lawani Samuel A. , Abdulmukaila M. T.
Published: October 2006

The quantities of cadmium, lead and mercury introduced into beans ground on domestic Nigerian grinding stones have been determined using colorimetric methods. The highest additions of cadmium, lead and mercury were 0.14, 0.72 and 0.17 mg kg−1, respectively. The corresponding lowest values were 0.01, 0.05 and 0.01 mg kg−1, respectively. These amounts introduced by the grinding stones are greater than the tolerable daily intakes recommended by the World Health Organisation.
The treatment of rapeseed meal and its effect on chemical composition and egg tainting potential
Authors: Roger Fenwick G. , Curl Caralyn L. , Pearson Arthur W. , Butler Edward J.
Published: October 2006

Treatment of high glucosinolate Brassica napus meals with lime, ammonia or by micronisation lowered their tainting potential by reducing their progoitrin, soluble tannin and sinapine contents. These effects were not sufficient to prevent inhibition of trimethylamine oxidation and the consequent rise in egg trimethylamine levels above the tainting threshold when the meals were fed to susceptible hens as sources of protein (100 g kg−1 diets).
Physical and chemical analyses of pigeonpea (Cajanus cajan) cultivars and F1 crosses
Authors: Yadav Satya P.
Published: October 2006

The weight of ‘dhal’ (the edible part of the seed) from 100 whole seeds, and the hull, protein, fat, starch and soluble carbohydrate contents of 12 pigeonpea (Cajanus cajan) cultivars and the F1 crosses were determined. The mean values for cultivars and the F1 crosses differed in 100‐seed wt, hull content (%) and protein and starch contents. Whereas 100‐seed wt showed a high positive correlation with the weight of dhal, its correlation was significantly negative with hull content (%) in cultivars and protein content in the F1 crosses.
The kinetics and mechanism of caffeine infusion from coffee: The effect of particle size
Authors: Spiro Michael , Selwood Robert M.
Published: October 2006

Measurements have been made of the rate of infusion of caffeine into distilled water from medium roast Kenyan Arabica coffee beans and from eight sieved fractions of the ground beans at 25.8°C. The first‐order rate constants increased dramatically as the particle size decreased. For one of the size fractions the rate constants were then measured at various temperatures up to 84.1°C and were found to rise eight‐fold over this temperature interval. The partition coefficients of caffeine between ground beans and water were also determined. These results, interpreted by a new steady‐state theory of extraction, show that the rate‐determining step in the infusion is diffusion of caffeine through the swollen coffee particles. The low magnitude of the diffusion coefficient and its high activation energy demonstrate that caffeine diffusion within the bean particles is a hindered process.
The determination of protein, fat and moisture in bread by near infrared reflectance spectroscopy
Authors: Osborne Brian G. , Barrett Gillian M. , Cauvain Stanley P. , Fearn Thomas
Published: October 2006

Near infrared (n.i.r.) reflectance spectroscopy has been employed for the determination of protein, fat and moisture in sliced white bread. N.i.r. reflectance at six wavelengths was measured using circular samples from each of six alternate slices taken from one half of each of 30 loaves of different composition. The six readings for each loaf at each wavelength were averaged and used to produce calibrations which, on prediction of the compositions of a further 30 loaves sampled in the same way, gave rise to standard deviations of differences between n.i.r. and standard procedures of 0.20% for protein, 0.18% for fat and 0.51% for moisture. Calibrations derived from the other halves of the loaves, which had been air‐dried and ground to a powder, resulted in similar standard deviation of differences for protein and fat.
Prediction of the nutritive value of forages by near infrared reflectance photometry
Authors: Bengtsson Staffan , Larsson Kjell
Published: October 2006

A filter‐type near infrared photometer equipped with 19 filters was used to predict crude protein, in‐vitro digestibility of organic matter, and in‐vivo and from in‐vitro predicted metabolisable energy in forages. The investigation was performed using pure species of grasses and legumes, grass/legume mixtures and grasses preserved by different methods. The need for specific calibrations is demonstrated. Results obtained using combinations of six filters selected during the calibration procedure were compared with those obtained using the six standard filters recommended for grain analysis. There were indications that selected filter combinations will only give accurate results if the composition of the test samples is very similar to that of the calibration samples, i.e. of the same species or family as the calibration samples. The correlation coefficient between manual methods and n.i.r. reflectance varied from 0.83 to 1.00 for crude protein, 0.48 to 0.91 for rumen digestible organic matter and 0.35 to 0.92 for metabolisable energy. When samples of grass silage were analysed using grass/legume mixtures for calibration of the equipment, the correlations were poor. Although the technique is satisfactory for determinating crude protein in forages utilised in practical farming, the need for specific calibrations when assessing in‐vivo organic matter digestibility or in‐vivo metabolisable energy renders it inferior to chemical/biological methods.
Effect of drought and irrigation on the fate of nitrogen applied to cut permanent grass swards in lysimeters: Leaching losses
Authors: Webster Colin P. , Dowdell Rodney J.
Published: October 2006

Nitrogen losses were measured in water draining from cut permanent grass swards growing in monolith lysimeters containing clay loam (Salop series) or silt loam (Bromyard series) soils. The swards were cut at 6‐week intervals during the summer and were fertilised with calcium nitrate at rates of 0 and 400 kg N ha−1 in each of five successive years (1977–81); in the first year the fertiliser was labelled with 15N. Four differing rainfall regimes were imposed from spring to autumn in each year. Mean annual losses of nitrogen by leaching from unfertilised swards were 3.8 kg N ha−1 with mean nitrate‐N concentrations in the water of about 1 mg N litre−1. In fertilised lysimeters where rainfall distribution was that of the long‐term average the mean annual total nitrogen losses were 41 kg N ha−1 in the Salop soil and 15 kg N ha−1 for the Bromyard soil; mean nitrate‐N concentrations were 11.6 mg N litre−1 and 5.1 mg N litre−1, respectively. Losses of nitrogen and nitrate concentrations were similar to these quantities when irrigation increased the rainfall total to 120% of average. Where a drought was imposed for 2 weeks before and after each cut, mean nitrate‐N concentrations increased to 20.3 mg N litre−1 on Salop soil and 13.1 mg N litre−1 on Bromyard soils; total annual nitrogen losses were 74 kg N ha and 33 kg N ha−1, respectively. The largest losses were recorded when the drought period extended for four weeks before each cut and mean nitrate‐N concentrations increases to 28.8 mg N litre−1 on Salop soil and 34 mg N litre−1 on Bromyard soil, with total annual nitrogen losses of 104 kg N ha−1 and 109 kg N ha−1, respectively. Losses of nitrogen derived from the fertiliser labelled with 15N were 7.3–8.4% of that applied in the Salop soil (29–33 kg N ha−1), with little effect by the differing rainfall distributions. On the Bromyard soil, losses were 3.7% (14 kg N ha−1) of the applied fertiliser in lysimeters not subjected to droughts. When the period of the drought extended before and after each cut, losses were 8.2% (32 kg N ha−1) and increased to 17.9% (70 kg N ha−1) when the drought period occurred entirely before each cut. Fertiliser nitrogen contributed 48–69% of the total nitrogen in drainage water from both soils in the first year.