bluuebunny/crossref_metadata_2025 huggingface dataset:
Volatile flavour components of dalieb (Borassus aethiopum L.)
Authors: Harper David B. , Nour Abdul Azim M. , Thompson Ronald H.
Published: October 2006

The volatile components of dalieb fruit have been investigated by capillary column gas chromatography/mass spectrometry. The main components were C1 to C4 aliphatic alcohols and the corresponding acids together with esters derived from them. Acetic acid and ethanol were particularly abundant, the fruit pulp containing approximately 0.1% of each compound. Other volatiles present included the unsaturated ketone 6‐methyl‐5‐heptene‐2‐one, the corresponding alcohol and the terpene, geranyl acetone.
Breakdown of resistant and readily digestible starch by human gut bacteria
Authors: Englyst Hans N. , Macfarlane George T.
Published: October 2006

Cooking and processing of starch‐containing foodstuffs results in a portion of the starch becoming resistant to hydrolytic enzymes secreted in the small intestine of man. In order to determine whether this resistant starch (RS) was degraded in the colon, samples of RS and readily digestible starch (RDS) for comparisons were incubated with (a) cell‐free supernatants from faecal suspensions and (b) washed faecal bacterial cell suspensions. The data obtained showed that, whereas pancreatic amylase and faecal supernatants hydrolysed RDS, with the production of oligosaccharides, RS totally resisted breakdown. In contrast, both RS and RDS were completely degraded by the washed bacterial cells with the generation of volatile fatty acids (VFA) and organic acids. Hydrolysis and fermentation of RDS was extremely rapid and, as a consequence, oligosaccharides and lactate initially accumulated in the culture medium. RS was broken down more slowly, howevér, and oligosaccharides and lactate never accumulated. The rate of polysaccharide hydrolysis had a significant effect on the quantities of VFA produced, in that 54% of carbohydrate was fermented to VFA in cultures incubated with RDS as sole carbon source as compared to only 30% in cultures incubated with RS. However no qualitative difference was observed in the VFA produced by fermentation of RDS or RS.
Preliminary observations on cooking quality parameters as indicators of adulteration of basmati rice
Authors: Vaingankar Nutan M. , Kulkarni Pushpa R.
Published: October 2006

Differential length‐breadth ratio and loss of solids in cooking water have been found to be reliable indicators of adulteration of Basmati rice with Saket‐4 rice, which is one of the rice varieties used frequently for adulteration.
Wheat trading in the republic of Ireland: The utility of a hardness index derived by near infrared reflectance spectroscopy
Authors: Downey Gerard , Byrne Seamus , Dwyer Elizabeth
Published: October 2006

The use of near infrared reflectance to measure kernel hardness in wheat is well established. Characterisation of wheat varieties grown commercially in the Republic of Ireland by this parameter revealed a bimodal hardness index distribution, with the degree of separation observed between the two varietal clusters being season‐dependent. With one exception, the varietal composition of each cluster was identical to that obtained by a classification on the basis of milling and bread‐baking quality. As the variety in question (Minaret) was not sown in 1983 and accounted for less than 2% of the commercial crop in the following year, hardness index measurement has been introduced by the trade as an indicator of milling and bread‐baking quality. The precision (standard deviation between duplicates =0.24) and reproducibility (2.5% misclassification rate) of this test was shown to be sufficient for the trading application envisaged.
Use of contact prints for recording polyphenoloxidase isoenzymes separated by electrophoresis
Authors: Watson Randall A. , Flurkey William H.
Published: October 2006

Crude extracts of polyphenoloxidase (PPO) (E.C. 1.14.18.1) from a variety of food and plant sources were subjected to polyacrylamide gel electrophoresis. Following electrophoresis, the gels were stained for enzyme activity using catechol and L‐dopa as substrates. Contact prints were made of the enzyme stained gels 30 min after enzyme staining and on the following day. The negative images (white bands on a dark background) clearly showed the number, type, mobility and variation in enzyme staining of isoenzyme forms of PPO separated by electrophoresis. Contact prints were used to identify PPO isoenzyme forms in the leaves, stipules, roots, and stems of broad beans. This method was also used to demonstrate that a single isoenzyme form of PPO in broad bean leaves decreased with leaf age. Photographs, using professional rapid process X‐ray copy film, were also taken of enzyme stained gels for comparison to contact prints. Using contact prints, permanent records of PPO isoenzyme forms can be obtained rapidly, are inexpensive, and reproduce actual gel patterns.
Preliminary studies on acidity‐astringency interactions in model solutions and wines
Authors: Guinard Jean‐Xavier , Pangborn Rose Marie , Lewis Michael J.
Published: October 2006

Intensity of astringency in model solutions and wines varying in total acid and total phenols was evaluated by paired comparisons by 10 trained judges. Model solutions consisted of tannic (500, 1000, 2000 mg litre−1) and tartaric (0, 2, 4, 6 g litre−1) acids dissolved in aqueous solutions of ethanol (120 ml litre−1) and sucrose (5 g litre−1). Wine solutions were prepared by addition of citric acid (0, 0.5, 1, 2, 3 g litre−1 as tartaric acid) to a high phenol‐red wine (2645 mg litre−1 GAE) and a moderate phenol‐white wine (800 mg litre−1 GAE). At all three levels of tannic acid, astringency of model solutions increased significantly (P<0.001) with tartaric acid concentration. Astringency of white wine also increased significantly (P<0.05) with citric acid concentration. A negative linear relation was found between relative astringency and pH at a given tannin level for both model solutions and white wine. As pH was reduced, more phenolic molecules were in the phenol form thereby increasing the likelihood of hydrogen bonding between hydroxyl groups of wine tannins and ketoimide groups of mouth proteins. The preliminary hypothesis that hydrogen bonding is the main reaction involved in the formation of protein‐tannin complexes resulting in the sensation of astringency was reinforced.
Aflatoxin determination in peanut butter by enzyme‐linked immunosorbent assay
Authors: Morgan Michael R. A. , Kang Angray S. , Chan Henry W.‐S.
Published: October 2006

High specificity, high titre antisera to aflatoxins B1 and G1 have been produced by immunisation of rabbits with a bovine serum albumin‐aflatoxin B1 conjugate. The antiserum has been used to set up an indirect, double antibody microtitration plate enzyme‐linked immunosorbent assay with a limit of detection of 0.1 pg toxin per well. The assay has been validated for application to peanut butter, and demonstrates many advantages over conventional methodology, including the requirement for minimal sample preparation before assay, its technical simplicity, and its potential high sample through‐put.
Dynamic rheological measurements on heat‐induced myosin gels: An evaluation of the method's suitability for the filamentous gels
Authors: Egelandsdal Bjorg , Fretheim Kristen , Harbitz Ole
Published: October 2006

Formation of bovine myosin gels (10 mg ml−1) by heat treatment at pH 6 and an ionic strength of 0.24 M has been monitored by using the Bohlin Rheometer System in the oscillatory mode. Rheological thermograms were determined with a general repeatability of about 2% for a given suspension. A pronounced maximum and an accompanying minimum in storage modulus (G′) were found at about 50 and 55°C, respectively. The thermograms for the loss modulus (G″) and the phase angle (δ) displayed complex behaviour as well, suggesting a multitransition process. Presumably, denaturational events in parts of the molecule are responsible for the complex rheology observed. This complexity is not related to trivial wall slippage as data obtained from cells with different gap sizes were highly reproducible and consistent with other measurements. A decrease in heating rate from 2.5 to 0.1°C min−1 had a large effect on G′; it increased from 905 to 1600 N m−2 for gels at 75°C. The phase angle was also affected by the heating rate, especially at about 55°C. The effect of increasing the strain from 0.003 to about 0.1 was significant in two temperature regions; G′ at temperatures higher than 65°C and δ at temperatures lower than 54°C increased with increasing strain.
Pyrazines in extruded malt
Authors: Fors Susan M. , Eriksson Caj E.
Published: October 2006

Green malt, partially dried, was processed by high‐temperature short‐time (HTST) extrusion cooking at three different temperatures. Volatile components of the product were analysed by gas chromatography (g.c.) using a headspace sampling technique, and identified by mass spectrometry (m.s.). The concentration of pyrazines increased when the temperature was increased from 130 to 160°C, but it fell at 190°C, probably as an effect of volatilisation. However, the influence of parameters such as water content, the milling of the raw material and its residence time in the extruder must also be taken into account. Extruded malt contained more total pyrazines than conventionally processed malt. 2‐Vinyl‐5‐methylpyrazine and 2‐vinyl‐6‐methylpyrazine were found only in extruded malt, especially at high processing temperature. The pyrazine content per colour unit was high, an observation which may lead to the production of a more flavourful beer of the lager‐type.
Nutritional evaluation of soya beans (glycine max): Nitrogen balance and fractionation studies
Authors: Grant George , McKenzie Norma H. , Watt William B. , Stewart James C. , Dorward Patricia M. , Pusztai Arpad
Published: October 2006

The poor nutritional performance of rats fed raw soya‐bean‐containing diets appeared to be due to reduced apparent digestion and absorption of dietary protein, coupled to changes in systemic metabolism leading to a poor overall nitrogen balance. Aqueous heat treatment greatly reduced but did not eliminate the antinutritional effect. Heat treatment with aqueous ethanol was more effective. The whey protein (pH 4.8 soluble extract) fraction contained the bulk of the trypsin inhibitor and haemagglutination activity and gave the poorest net protein utilisation value. However, an eight‐fold increase in trypsin inhibitor content did not significantly effect apparent nitrogen digestibility. Therefore inhibition of gut proteolytic enzyme activity in vivo by soya bean trypsin inhibitors did not account fully for the poor nutritional performance. The problems elicited by soya bean are not transitory and thus there was a cumulative deterioration in overall performance for 16 weeks as a result of continuous exposure to soya bean.
Cadmium in roadside grapes
Authors: Marletta Giuliana Pertoldi , Favretto Luciana Gabrielli , Favretto Luciano
Published: October 2006

The concentration of cadmium in unwashed wine grapes and leaves is considered as a function of the distance from the suspected source, an isolated straight road. Cadmium levels were determined by a.a.s. with electrothermal atomisation in a graphite furnace. The grape and leaf samples display an asymptotic decrease in cadmium concentration (c) according to the distance (d) from the edge of the road. The observed data can be fitted with the exponential function c=A+B exp (‐Cd), the parameters being estimated by least‐squares non‐linear regression. The simple model allows the determination of the cadmium level at d→∞ (A) and at d=0 (A+B). The results obtained indicate that the effect of the presence of the road is not detectable beyond a distance of 50 m.
Saponin content of chickpea and black gram: Varietal differences and effects of processing and cooking methods
Authors: Jood Sudesh , Chauhan Bhag M. , Kapoor Amin C.
Published: October 2006

Differences were observed in saponin contents of eight varieties of chickpea (Cicer arietinum) and four of black gram (Phaseolus mungo). Common domestic processing and cooking treatments reduced the saponin level of the pulses significantly. Sprouting had the most pronounced effect followed by autoclaving, soaking and ordinary cooking. Cooking of soaked as well as unsoaked seeds had a similar diminishing effect.
Effects of food processing and fruit juices on in‐vitro estimated iron availability from cereals, vegetables and fruits
Authors: Hazell T. , Johnson I. T.
Published: October 2006

Selected processed foods were digested in vitro under simulated physiological conditions. The proportion of iron diffusing across a semi‐permeable membrane was used as an index of bioavailability. Certain food processing procedures appeared to greatly enhance the proportion of diffusible iron. Many of the foods that were canned, dried, pickled, fermented, refined, or which contained certain additives, displayed enhanced iron diffusibility compared with unprocessed foods. Iron diffusibility from wheat flour was found to be enhanced by the addition of fruit juices. The constituent organic acids in the fruit juices, namely citric, ascorbic and malic, were found to be potentially responsible for this enhancement. These three compounds are also important examples of a sequestrant, an antioxidant, and an acidulant. These and similar compounds are added to many processed foods in order to improve their quality and preservation. All such additives have the potential to influence the chemical form, and probably the bioavailability, of food iron.
Inter‐relationships between acidic and alkali treatments of cotton straw and wheat straw and their fibre chemical properties
Authors: Silanikove Nissim , Levanon Dan
Published: October 2006

The amount of lignin in the cell walls of cotton straw (CS) and wheat straw (WS) was found to be the same, but the ratio between lignin and hemicellulose was considerably lower in CS than in WS. In CS the amount of soluble acid lignin was less than 1% of the total lignin, whereas in WS it was 20%.

The amount of phenolics in concentrated sulphuric acid (72%) hydrolysates of the cell wall was reduced drastically in WS compared with the amount released by diluted (1 N) sulphuric acid; this may have been due to polymerisation of low‐molecular‐size lignin.

The amount of alkali‐soluble lignin in WS was 3–7 times greater than in CS. Following acid treatment the amount of alkali‐soluble lignin was reduced from 20% of the total content to 5% in WS, and from 5% to 1% in CS.

Enzymic hydrolysis was 49% higher in WS cell wall than in CS cell wall. In WS, acidic and alkali pretreatments followed by cellulase treatment increased glucose yield from cellulose by 260% and 280%, respectively. In CS, acidic pretreatment did not affect the glucose yield from cellulose, whereas alkali treatment increased it by 35%.
The effect of vacuum packaging on the microbial spoilage and shelf‐life of ‚ready‐to‐use’︁ sliced carrots
Authors: Buick Robert K. , Damoglou Anthony P.
Published: October 2006

The effect of vacuum packaging on the microbial spoilage of ‚ready‐to‐use’︁ carrot slices and on the effect on shelf‐life of the product is reported. The microbial development on vacuum packaged carrots was slower than that of non‐vacuum packaged material. The predominant organisms present were Leuconostoc spp. in the vacuum packs as opposed to Erwinia spp. in the aerobic packs. Vacuum packaging of the sliced carrots significantly extended the shelf‐life of the product when stored at 4°C from 5 to 8 days.
Air classification of flours of three legume species: Fractionation of protein
Authors: Cloutt Pauline , Walker Ann F. , Pike Derek J.
Published: October 2006

The effect of changing the cut point of a laboratory air classifier on the protein fractionation into the fines was studied on the flour of two varieties each of cowpea (Vigna unguiculata), faba bean (Vicia faba) and pigeonpea (Cajanus cajan). Of the three species, the highest fines protein content (56.5–62.7% Nx6.25 over the range of cut points studied) and protein recovery (44.2–86.5% over the range) was for one variety of faba bean. The other variety of faba bean showed lower values. Fines from cowpea and pigeonpea flour contained protein contents in the range 26.5–46.8%, depending on cut point, with protein recoveries of 28.3–63.5%. Plots of dry weight yield vs. protein content of fines indicate that once the relationship between these two parameters has been established for a given species (or, in the case of faba bean, for variety), then the protein content of fines can be predicted from dry weight yield.
The use of near infrared reflectance spectroscopy for predicting the quality of grass silage
Authors: O'Keeffe Michael , Downey Gerard , Brogan James C.
Published: October 2006

Near infrared reflectance spectroscopy, using a fixed‐filter instrument fitted with 19 filters, was evaluated for the prediction of crude protein and in‐vitro dry matter digestibility in commercial farm grass silage. Crude protein (6.5–17.6%) was estimated with acceptable accuracy (standard error of prediction=0.63%) using a six‐wavelength calibration, but in‐vitro dry matter digestibility (40.7–69.9%) was not predicted with sufficient accuracy (standard error of prediction=2.96%) by this technique.
The ratio of B to C hordeins in barley as estimated by high performance liquid chromatography
Authors: Griffiths D. Wynne
Published: October 2006

The ratio of B to C hordeins was determined using high performance liquid chromatography (h.p.l.c.) for a range of spring barley cultivars and the values obtained varied from 1.79 for Kneifel to 4.15 for Goldmarker. Fine grinding of seed samples resulted in a significant increase in the quantity of protein solubilised but relatively little difference was observed in the B and C hordein ratio, which appeared to be independent of protein extraction efficiency. Increased nitrogen content significantly changed the ratio by increasing the proportion of C hordein. A highly significant correlation was found between the B and C hordein ratio and sample nitrogen content. Analysis of single seeds selected at random from within a single sample of Goldmarker revealed considerable variability in the B and C hordein ratios with values differing by over 2 units. Due to the sensitivity of the B to C hordein ratio to various environmental effects, it is unlikely that the ratio will be of great value as an unambiguous aid in the identification of barley cultivars.
Varietal variation and correlation of trace metal levels with ‚catechins’︁ and caffeine in Sri Lanka tea
Authors: Ramakrishna Rasiah S. , Palmakumbura Senerath , Chatt Amares
Published: October 2006

Trace elements, phosphorus, ‚catechins’︁ and caffeine levels in different varieties of Sri Lanka tea have been determined. The range and mean of zinc, copper, iron, lead and cadmium in 73 tea samples were as follows: zinc 22.5–62.5 and 35.0 μug g−1, copper 10.0–25.0 and 17.8 μug g−1, iron 40.0–185.0 and 128.1 μug g−1, lead 0.188–0.561 and 0.426 μug g−1, cadmium 0.156–0.380 and 0.239 μug g−1. Significant differences in zinc, iron, lead and cadmium were observed among tea varieties grown at different elevations in Sri Lanka. These levels were also compared with results obtained with samples from other countries. The phosphorus content in ‚black tea’︁ showed correlations with trace metal levels in the order lead>zinc>iron>copper>cadmium. Positive correlation with levels of ‚catechins’︁ were more significant with zinc and cadmium. Caffeine levels were found to be significantly correlated with lead and zinc in ‚black tea’︁. Studies of translocation of trace metals from soil have involved analysis of various parts of the tea shoot and supporting soil.
Total, non‐volatile free fatty acids as a freshness index for hake (Merluccius hubbsi) stored in ice
Authors: Barassi Carlos A. , Pécora Rolando P. , Roldán Hugo , Trucco Raúl E.
Published: October 2006

Total, non‐volatile free fatty acids (FFA) content was determined in hake muscle during fish storage in ice. FFA increased linearly in every season according to freshness loss as determined by sensory scoring. FFA determination is proposed as a valuable alternative to sensory scoring in determining fish deterioration in ice.
Isolation and properties of the lectins from the tuberous roots of winged bean Psophocarpus tetragonolobus (L.) DC
Authors: Kortt Alexander A. , Caldwell J. Bruce
Published: October 2006

The tuberous roots of winged bean (Psophocarpus tetragonolobus (L.) DC) contain two distinct groups of lectins corresponding to the acidic and basic lectins of the seed. The tuber isolectins were separated by chromatography on Ultrogel AcA44 and SP‐Sephadex C‐25, and purified by affinity chromatography. The acidic and basic lectins were also isolated from tuber extracts in a single step by affinity chromatography on lactose‐Sepharose 6B and melibiose Bio‐Gel P150, respectively. The lectins isolated from the tubers of six varieties of P. tetragonolobus showed no significant differences in their properties. The molecular and physicochemical properties of the tuber acidic and basic lectins were essentially identical to that of the corresponding winged bean seed lectins; the only exception was a small difference in the isoelectric points of the subunits of acidic lectins of seed and tuber as observed on isoelectric focusing in 8 m urea.
Effect of steam‐hydrothermal treatment (SHTT) on the physico‐chemical properties of cassava (Manihot esculenta crantz)
Authors: Raja K. C. M. , Ramakrishna S. V. , Mathew A. G.
Published: October 2006

Effect of steam‐hydrothermal treatment (SHTT) on functional properties of cassava was studied using fresh tubers of cultivar Malayan‐4 (M‐4). Fresh slices were steam‐processed for 5, 10 and 20 min at atmospheric pressure. Plain‐dried samples were also prepared for comparison. SHTT samples were found to have higher rehydration capacity, equilibrium moisture content by soaking (EMC‐S), and sedimentation volume at room temperature (28–30° C). These samples also showed a lower amylose content than plain‐dried samples. Electrolytes like sodium chloride, sodium sulphate and sodium phosphate at 1–0 N concentration changed the sedimentation volume, especially of SHTT sample:. Paste stability of steam‐processed samples at cooking temperature (95° C) was relatively higher than plain‐dried ones. Among the three SHTT samples, that steam‐processed for 10 min showed the highest paste consistency and set‐back ratio. X‐ray diffraction pattern of flour prepared from SHTT samples indicated a clear shift from crystalline to a partially amorphous state. Infra‐red spectra of cassava starch and flour samples were generally identical.
Salt conditions and the effectiveness of poly(vinyl alcohol) in reclamation of saline‐sodic soils
Authors: Nawar Nima K. , Petch James R.
Published: October 2006

Fully hydrolysed poly (vinyl alcohol) (PVA) with molecular weight 14000 was effective in reducing or preventing clay dispersion when columns of mixed sand/Na‐soil aggregates containing a wide range of NaCl salt contents were leached with distilled water. The maximum effect was obtained over a range of soil salt contents in which the applied polymer remained soluble. Above this range, because of polymer precipitation, effectiveness was inversely related to salt content. For soil aggregates with different exchangeable sodium percentage (ESPs), PVA was also effective in reducing or preventing dispersion in water and maintaining the relative hydraulic conductivity of soil columns leached successively with diluted solutions. However, a further relationship was found which showed that the polymer was more effectively incorporated in soils with higher ESP. This was reflected in measurements of dispersion and may be explained by the greater effect of drying (at 70°C) and by the greater adsorption of PVA in the presence of exchangeable sodium than exchangeable calcium.
A Screening method for total oxalate determination in plant material by gas chromatography
Authors: Sutikno A. Irawan , Suherman D. , Tangendjaja B.
Published: October 2006

Oxalates in plant material can be methylated directly to from dimethyl oxalate. After addition of water and chloroform, the volatile compoun is extracted into the organic phase and analysed quantitatively by gas chromatography.

Some forms of oxalates are difficult to methylise, and this is apparent when 20% boron trifluoride‐methanol is used as the methylating reagent. The use of 7% hydrochloric acid‐methanol improved methylation, but the best result was obtained by repacing the acid catalyst with sulphuric acid and increasing the acid concentration up to 30%. Using this reagent, recovery from spiked samples was satisfactory (ranging from 92 to 105%), and precision of the method was good (Relative Standard Deviation (RSD) 1.3% at a total oxalate content of 1.95%).
Screening of tomato purée for excessive mould content by near infrared spectroscopy: A preliminary evaluation
Authors: Davies Anthony M. C. , Dennis Colin , Grant Alex , Hall Martin N. , Robertson Alastair
Published: October 2006

Preliminary experiments demonstrated that near infrared spectroscopy (n. i. r.s.) could be used to measure the amount of mould (Botrytis cinerea or Alternaria tenuissima) added to fresh tomato homogenate. In subsequent work, fresh tomatoes that had been allowed to become mouldy were used to prepare a series of tomato purées containing known quantities of mouldy fruit. N.i.r.s. of the freeze‐dried purée was again successful in estimating the amount of contamination as per cent mouldy fruit. Regression analysis selected wavelengths which could be associated with absorption bands of chitin, the major carbohydrate in the cell walls of moulds. It may therefore be possible to utilise n.i.r.s. as a screen for mould in tomato purées if the present success with B. cinerea and A. tenuissima can be extended to the complete range of moulds encountered in tomato products.
Hydroxycinnamate esters of Vitis vinifera: Changes during white vinification, and effects of exogenous enzymic hydrolysis
Authors: Somers T. Chris , Vérette Eric , Pocock Ken F.
Published: October 2006

The composition of total hydroxycinnamates, as determined by high‐performance liquid chromatography (h.p.l.c), changes progressively during vinification, with little alteration in the ultraviolet spectrum. Enzymic activity during crushing and juice preparation leads to variable concentration of a glutathione derivative of the major component, caffeoyl tartaric acid. After fermentation begins, there is then partial hydrolysis of tartaric acid esters to free hydroxycinnamic acids, and formation of ethyl esters. Ten hydroxycinnamate and hydroxycinnamic acid components, all having tram‐configuration, were identified in a young Riesling wine. The course of phenolic change during commercial vinification of Chardonnay grapes was also examined. All components were quantitated as mg litre−1 ‘caffeic acid equivalents’ (CAE). Spectral estimates at 320 nm of total hydroxycinnamates as mg litre−1 CAE were 10‐15% higher than integrated h.p.l.c. measures of individual components. Six months after vintage, total hydroxycinnamates were 80% of amounts originally present. Use of a specific enzyme, hydroxycinnamic acid ester hydrolase, gives rapid alteration of phenolic composition in white wines. Sensory assessment of the effect of such treatment is reported for treatment of the Chardonnay wine.
Effects of silicone and ascorbyl palmitate on the quality of palm olein used for frying of prawn crackers
Authors: Augustin Mary Ann , Chua Carlton J. J. , Heng Lee Kheng
Published: October 2006

The effects of ascorbyl palmitate (AP) and silicone on the quality changes of refined, bleached and deodorised palm olein (RBD olein) during intermittent frying of prawn crackers for 4.5 h per day were evaluated. The percentage polar components, the C18:2/C16:0 fatty acid ratio, and the acid value of used frying oil without additives were comparable to those for oil containing 200 mg kg−1 AP. Oil with 2 mg kg−1 silicone as well as oil containing 200 mg kg−1 AP plus 2 mg kg−1 silicone that had been used for frying had lower percentage polar components, higher C18:2/C16:0 ratios and lower acid values than RBD olein without additive. The results showed that silicone had a protective effect on the oil but that the rate of deterioration of the oil in the presence of AP was comparable to that of oil without additive during frying of prawn crackers. The results also showed that the extent of oil oxidation in RBD olein subject to static heating at 180°C for 4.5 h per day for four consecutive days was comparable to that of RBD olein without additive that had been used for frying of prawn crackers.
The effect of casein, urea and dried poultry waste on the fermentation of starch or cellulose measured in vitro
Authors: Akbar M. Ali , Scaife Jeremy R. , Topps John H.
Published: October 2006

Comparative studies on the effects of casein, urea and poultry waste on the fermentation of starch and cellulose were conducted. Incubation of starch with poultry waste for 390 min resulted in greater overall gas, total VFA and ammonia production than in control incubations (grass cubes and hay). Between 210 and 390 min the ammonia concentration fell, indicating microbial utilisation of nitrogen. Replacement of poultry waste with casein resulted in lower gas and total VFA production and similar ammonia concentrations in comparison with the control incubation. When starch was incubated with urea, the ammonia concentration rose rapidly, causing an elevated pH and poor VFA production. When cellulose was incubated with any of the three nitrogen sources, gas and total VFA production were considerably lower than in control incubations. Inclusion of urea as a nitrogen source had an effect on cellulose fermentation similar to that seen with starch. When grass cubes and hay were incubated with poultry waste, gas production was similar to that of the control; however, ammonia and total VFA production were greater than in the control. The results indicate that the carbohydrate content of poultry waste may be useful in promoting the establishment of fermentation, and that the slow release of ammonia may facilitate a more efficient fermentation of roughage in nutrients such as grass and hay.
Some biochemical evaluation of fluted pumpkin seed
Authors: Asiegbu Jerry E.
Published: October 2006

Analysis of fluted pumpkin seed Telfairia occidentalis Hook f. gave protein of 31.1% and oil 47%. The protein is markedly deficient in the sulphur‐containing amino acids (methionine and cystine) followed by lysine, valine, isoleucine and phenylalanine. The oil could be useful for cooking purposes, and the high degree of unsaturation might enable it to be used as a drying oil for paints and varnishes.
Modified‐atmosphere retail packaging of discovery apples
Authors: Smith Steve M. , Geeson John D. , Browne K. Martin , Genge Pia M. , Everson Helen P.
Published: October 2006

An experimental modified‐atmosphere packaging system was used to compare the atmospheric compositions that developed within sealed packs made from a range of films of different permeability properties. The effects of these conditions were then related to the primary quality attributes, i.e. background skin colour and flesh firmness, and the sensory quality of Discovery apples. Concentrations of CO2 and O2 within packs were dependent on the permeability of the film and the holding temperature. In packs sealed with low density polyethylene films and held at 20°C, equilibrated atmospheres containing 3‐5% CO2 and 5‐6% O2 developed within 1‐2 days. Softening and yellowing of fruit was markedly retarded. In packs sealed with some less permeable films, atmospheres containing 12‐20% CO2 and 0.9‐4% O2 developed within 1‐2 days, resulting in retarded softening and yellowing of the fruit but also a high incidence of tainting. Possible commercial applications, benefits and limitations of modified‐atmosphere packaging are discussed.
Absorption of tricarballylic acid from the rumen of sheep and cattle fed forages containing trans‐aconitic acid
Authors: Russell James B. , Mayland Henry F.
Published: October 2006

Some forages accumulate high concentrations (< 5% of dry matter) of trans‐aconitate, and this acid has been implicated in Mg chelation and the occurrence of grass tetany in ruminants. In vitro experiments have indicated that rumen microorganisms convert trans‐aconitate to tricarballylate. The feeding studies described here were conducted to demonstrate absorption of tricarballylate by ruminant animals fed diets similar to those producing grass tetany. When sheep were switched from a diet containing alfalfa (lucerne) (Medicago sativa L.) hay (no detectable trans‐aconitate) to wheat (Triticum aestivum L.) and rye ( Secale cereale L.) forage containing 1.52 and 1.37% trans‐aconitate, respectively, there was a rapid increase in blood plasma tricarballylate. Trans‐aconitate was not detected in the plasma. At 16 h after feeding, plasma tricarballylate concentrations were 0.58.0.08 and 0.48.0.21 mM in sheep fed the wheat and rye forage, respectively. Tricarballylate concentrations remained relatively constant for the remaining 60 h of the experiment. Cattle were fed rye forage one week later, and the concentration of trans‐aconitate in the forage had dropped to 0.83% of the dry matter. Once again there was a rapid appearance of tricarballylate in plasma, but the maximum concentration was 0.31.0.05 mM (t = 27 h). When the cattle were removed from the rye forage, there was a linear decline in tricarballylate and none was detected 24 h later. The studies indicated that trans‐aconitate is converted to tricarballylate in the rumen and that tricarballylate rather than trans‐aconitate is absorbed.
Comparison of three standard solvent extraction procedures for the determination of oil content in commercial oilseed samples
Authors: Kershaw Stephen J. , Hackett Frank
Published: October 2006

Three standard extraction procedures (FOSFA, IASC, ISO) for determining oil content were compared for 15 different oilseeds. Differences between results obtained using these three procedures were not statistically significant and repeatabilities were good. The general use of sand to aid microgrinding procedures and of an initial extraction period of 2 h only is recommended.
The contribution of trypsin inhibitors to the nutritional value of chick pea seed protein
Authors: Sastry M. C. Shamanthaka , Murray David R.
Published: October 2006

The trypsin inhibitors (TI) from seeds of chick pea (Cicer arietinum L.) were isolated using trypsin–Sepharose 6B affinity chromatography and found to constitute 5.03% of extractable seed protein. The TI consisted predominantly of low molecular weight species, estimated at 9000 and 8000 daltons by disc gel electrophoresis. Polypeptides in these regions of the gel were preferentially labelled by 35SO2‐4 fed via the cut stem to fruiting stalks of chick pea plants. A molar ratio of 1.8 was determined for the inhibition of trypsin by these inhibitors, whereas chymotrypsin was uninhibited. They are therefore ‘double‐headed’ inhibitors with both sites specific for trypsin, rather than with one site specific for each of trypsin and chymotrypsin, as reported for other lines of chick pea. Thus TI may contribute to the high quality of the albumin fraction of chick pea seeds in two ways: by virtue of their contents of essential amino acids, and by their failure to affect chymotrypsin.
Deterioration of shelled oil palm kernels caused by seedborne fungi
Authors: Airede Catherine E. , Esuruoso Oladele F.
Published: October 2006

Autoclaved oil palm kernels were inoculated with spores of seedborne isolates of either Aspergillus flavus, A. niger, Penicillium chrysogenum, P. janthinellum, Paecilomyces varioti, Syncephalastrum racemosum or Fusarium oxysporum. At 0, 2, 4 and 8 weeks after inoculation, determinations were made of the moisture content, oil, free fatty acids (FFA), sugars and protein nitrogen. The principal biochemical changes induced by these fungi were increases in moisture content and FFA, decreases in total oil and total sugars and a degradation of protein nitrogen. Aspergillus flavus caused the greatest changes, and P. varioti caused the least changes under the moisture conditions of this experiment. The main type of deterioration was hydrolytic rancidity of the oil, resulting in a dark reddish‐orange‐coloured oil and a discoloration of the kernel meal.
Effect of chemical treatment on the fatty acid composition of european cucumber fruit during cold storage
Authors: Geduspan Haydee S. , Peng Andrew C.
Published: October 2006

Mature green European cucumber fruits (Cucumis sativus L. cv. ‘V‐5’), grown in the greenhouse, were treated with butylatedhydroxytoluene (BHT) and calcium chloride, stored at 4°C for 7 days and transferred to 20°C for another 7 days. There were no visible symptoms of chilling injury on cucumbers during cold storage, but surface pitting and shrinking started 2 days after fruits had been transferred to 20°C. Total lipid content was not affected by chilling or chemical treatment, but changes in the lipid classes were observed. Neutral lipids were increased and phospholipids decreased. Laurie and myristic acids were decreased by chilling and chemical treatment, and palmitic acid increased in each lipid class with BHT treatment. Linoleic acid was increased by CaCl2treatment in each fraction. Linolenic acid response varied with chilling and chemical treatment. The unsaturation ratio of 18‐carbon acids was increased for total lipids and phospholipids.
The influence of nitrogen and early drainage on production from grazed and cut grassland restored after opencast mining
Authors: Baker Anne‐Marie , Younger Alan
Published: October 2006

A review of past and present grassland management on land restored from opencast mining suggests that the most noticeable changes have been increased nitrogen fertiliser use and earlier installation of permanent under‐drainage.

A programme of research is described which aimed to examine the effect of early drainage on perennial ryegrass (Lolium perenne S23) grown for grazing, frequent cutting or silage production on sites previously opencast mined for coal, and to consider how these options affected both the short‐term productivity and the long‐term restoration of the soil.

The results demonstrate that satisfactory herbage production is possible on restored land provided moderate levels of fertiliser are applied. Grass was utilised at high levels of intensity with no detrimental effects on sward or soil. Highest yields were obtained when grass was cut for silage, and under this regime early drainage led to a significant increase in herbage production each year of the study. When grazing was practised, drainage only led to increased total herbage production in wet years although benefits were seen in spring and in the overall sheep carrying capacity of the land. Clover inclusion in the cut swards only increased yield when less than 200 kg N ha−1 year−1 was applied.
The zinc(II) binding sites of soya bean glycinin
Authors: Nosworthy Neil , Caldwell Robert A.
Published: October 2006

Binding of zinc by glycinin was determined in 0.5 M KCl at pH 6.2. The number of binding sites in the native protein was 51 for 8.5 μM glycinin. Protein modification studies identified the histidine residues as one of the binding sites, and comparison with published data on the histidine content of glycinin suggests that the majority of these residues are on the surface of the protein. Denaturation by 6 M urea increased the number of binding sites to 330. The number of zinc binding sites was found to vary with the protein concentration in 0.5 M KCl. The affinity of zinc for the protein varied with the protein concentration. Increasing the KCl concentration to 1.0 M decreased the affinity of zinc for the protein and increased the number of binding sites. Zinc preferentially binds to EDTA rather than to glycinin. Binding at pH 5.5 resulted in a reduction in the number of binding sites to 23. Ultracentrifugal analysis of glycinin in the presence and absence of zinc gave S20, W values of 13.1 and 11.1, respectively. Calcium and magnesium did not bind to glycinin in 0.5 M KCl at pH 6.2.
Structure of a major pea seed albumin: Implication of a free sulphydryl group
Authors: Gruen L. Clem , Guthrie Robin E. , Blagrove Robert J.
Published: October 2006

Recent studies in a number of laboratories have characterised many of the properties of a major pea albumin (designated PMA or PA2: subunit Mr∼26 000) which is not readily degraded in the cotyledon upon germination. In the present report, some of the physicochemical properties of this protein have been studied in greater detail. A non‐helical structure, stable at high pH, is evident. Of special significance is the presence of a single free sulphydryl group, although studies reported elsewhere show that the protein consists of four copies of a strongly conserved repeated sequence. It is postulated that this free sulphydryl group in PA2 (5–10% of total pea seed protein) causes polymerisation through disulphide interchange and thereby is a likely source of partial insolubility in protein isolates following an initial alkaline extraction.
Recovery of 15N‐labelled urea applied to the foliage of winter wheat
Authors: Powlson David S. , Poulton Paul R. , Penny Alexander , Hewitt Michael V.
Published: October 2006

15N‐labelled urea (30 kg N ha−1) was sprayed on to the foliage of winter wheat at four sites where sufficient fertiliser N had previously been applied to the soil to achieve approximately maximum yield. Half of the urea was applied shortly before anthesis (growth stage, GS, 37‐39) and half after anthesis (GS 69–73), both portions being labelled. Averaged over all sites, 62% of the urea N was recovered in the crop (range: 45–77%). On average, 89% of the urea N recovered in the crop was in grain, a rather greater proportion than from applications of N to soil in spring. Foliar‐applied N (30 kg ha−1) increased %N in grain as much as an additional 60 kg N ha−1 applied to soil in February but slightly less than an extra 60 kg ha−1 applied to soil in April. Foliar N did not alter yield or 1000 grain weight at any site, and where a breadmaking wheat (cv. Avalon) was grown had no adverse effect on Hagberg Falling Number or grain nitrogen/sulphur ratio.
Effects of limited proteolysis on broad bean polyphenoloxidase
Authors: King Rebecca S. , Flurkey William H.
Published: October 2006

Partially purified broad bean polyphenoloxidase was treated with a variety of proteases. Enzyme activity increased after treatment with chymotrypsin, pepsin, subtilisin, thermolysin, trypsin, and Staphylococcus aureus V8 protease but this activation was masked when assayed in the presence of sodium dodecylsulfate. The enzyme was resistant to proteolysis when treated with chymotrypsin, elastase, pepsin, thermolysin, and V8 protease. Proteinase K, subtilisin and trypsin treatment resulted in partial degradation of the enzyme but only trypsin generated an active enzyme form with a slightly smaller molecular weight. Electrophoresis, followed by enzyme staining and or Western blotting, showed that trypsin treatment converted the active 45 kd enzyme into a 43 kd enzyme within 20 min. Treatment with proteinase K, subtilisin and trypsin also produced inactive higher molecular weight forms of purified polyphenoloxidase that were identified by Western blotting. The use of antibodies coupled with Western blotting also identified inactive, active, and latent polyphenoloxidase after protease treatment, and suggests that immunological methods can be used to establish the types and amounts of polyphenoloxidase present in a given tissue.
Purification of a lectin from Winged bean (Psophocarpus tetragonolobus (L.)DC) tubers by affinity chromatography
Authors: Shet Manjunath S. , Madaiah M.
Published: October 2006

A lectin from the tuber of winged bean, Psophocarpus tetragonolobus (L.) DC, has been isolated and purified by affinity chromatography using D‐galactose linked Sepharose‐6B, followed by CM‐Sephadex C‐50. The homogeneity of the lectin was confirmed by PAGE at pH 4.5, SDS—PAGE and gel filtration. It is a glycoprotein with a relative molecular mass (Mr) of 29 000±1000 and 46 000±2000 by SDS—PAGE and gel filtration on Biogel P‐150, respectively. SDS—PAGE in the presence of 2‐mercaptoethanol gave two closely migrated protein bands corresponding to a molecular mass of 14 000 and 15 000. The total carbohydrate content was found to be 7%. The tuber lectin agglutinates both trypsinised and untrypsinised erythrocytes of human blood groups (A, B and A B), rabbit and rat but not sheep and human O group erythrocytes. The lectin is inhibited by D(+) galactose and galactose containing di‐ and trisaccharides. o‐ and p‐Nitrophenyl α‐galactopyranosides are found to be the most potent inhibitory sugars.
Application of principal component analysis to the prediction of lucerne forage protein content and in vitro dry matter digestibility by NIR spectroscopy
Authors: Bertrand Dominique , Lila Marc , Furtoss Vincent , Robert Paul , Downey Gerard
Published: October 2006

Application of principal component regression (PCR) was proposed for the development of a prediction equation of forage composition by near infra‐red spectroscopy. PCR involves two steps: (a) the creation of new synthetic variables by principal component analysis (PCA) of spectral data, and (b) multiple linear regression with these new variables. Results obtained by this procedure have been compared with those generated by the conventional application of multiple linear regression (MLR) on spectral data. The comparison used the determination of protein content and in vitro dry matter digestibility (IVDMD) in 345 samples of lucerne forages. For protein determination, results of both procedures were quite similar (correlation coefficients: 0.978 and 0.980; standard errors of calibration: 0.86 and 0.84% DM; standard errors of prediction: 0.81 and 0.80% DM respectively for MLR and PCR prediction equations). The same was observed for IVDMD determination (correlation coefficients: 0.942 and 0.951; standard errors of calibration: 1.89 and 1.71% DM; standard errors of prediction: 2.22 and 2.22% DM, respectively). A large number of PCA variables were necessary for an accurate prediction of both constituents. The influence of the number of regression terms introduced in the PCR equation has been studied. The criterion for stopping the introduction of new terms in PCR did not seem as critical as in MLR.
Rumen degradation of cell wall polysaccharides in untreated and alkali‐treated straws and cereal brans
Authors: Ternrud Ingrid E. , Lindberg Jan E. , Magnusson Ann‐Therese , Theander Olof
Published: October 2006

Rumen degradation of cell wall polysaccharide constituents using the in sacco technique was studied for untreated cereal brans (oats, wheat and barley) and nine technically alkali‐treated batches of barley straw. The alkali treatment included four ammonia treatments, two dry sodium hydroxide treatments and three wet sodium hydroxide treatments. On degradation of the cell wall polysaccharides, their main constituents, xylose and glucose, were released at about the same rate for the ammonia treatments and the dry sodium hydroxide treatments. For the wet sodium hydroxide treatments the degradation of the xylose residues was faster than the liberation of the glucose residues. For all treatments the liberation of the arabinose residues was faster than that of the xylose and glucose residues. The reason for the increased digestibility of the cell wall polysaccharides is suggested to be the breaking of ester and hydrogen bonds and the breaking of alkali‐labile linkages in lignin, as well as changes in the surface layer of the straw. For the wet sodium hydroxide treatments the larger amount of water present during the alkali treatment processes is suggested to increase the diffusion of the alkali into the straw and to translocate a part of the hemicellulose. On the degradation of wheat and barley bran the liberation of xylose residues was fast whereas xylose and arabinose residues in oat bran were slowly liberated.