bluuebunny/crossref_metadata_2025 huggingface dataset:
Some studies of the nutritive value of high‐lysine barleys
Authors: Johnson Ian L. , Carpenter Kenneth J. , Hurrell Richard F. , Miller Eric L. , Rhodes Anthony P.
Published: November 2006

In five separate experiments, three high‐lysine (HL) barley lines were compared with the HL mutant Risø 1508 and the normal variety Maris Mink (MM), for their lysine content, protein quality and metabolisable energy (ME). The HL barley lines were selected from crosses between Risø 1508 and Julia or Lofa Abed. Lysine content (g/16 g N) as measured by four different procedures was found to be from 11 to 28% higher in the HL barleys compared to MM. True nitrogen and lysine digestibility were only slightly reduced (6 and 4%, respectively) in the HL barleys when they were fed as the sole N source in purified diets for rats in an N‐balance trial. A subsequent 17% improvement in protein retention efficiency (PRE) was noted in the rat trials when the HL barleys provided the N source rather than MM. Further supplementation with lysine did not improve PRE values for the HL barleys though a significant response was noted with MM samples. Although the gross energy content of all the barleys was similar, the ME values of the HL barleys were some 8‐15% lower than the corresponding values for MM. The reasons for this and the potential economic value of these HL barleys are discussed.
Effects of direct drilling and ploughing on root distribution in spring barley, and on the concentrations of extractable phosphate and potassium in the upper horizons of a clay soil
Authors: Drew Malcolm C. , Saker Leslie R.
Published: November 2006

A comparison was made between the effects of three consecutive years of either direct drilling or ploughing, on the distribution of extractable soil phosphate and potassium, and the distribution of roots of a spring barley crop in the upper 20 cm of the soil. Samples were collected from a clay soil (Evesham series) in June 1975 when the crop was mid‐way through the phase of stem extension (Feeke's growth stage 7–8). With ploughing, the concentration of nutrients was approximately uniform to the maximum depth of cultivation (20 cm). With direct drilling there were markedly higher concentrations of phosphate and potassium in the upper 5 cm of the soil, but at depths between 10 and 20 cm the concentrations of potassium, and particularly phosphate, were lower than with ploughing. Root weight and length, per unit soil volume, in the upper 5 cm, were also greater with direct drilling than with ploughing. However, the more superficial distribution of phosphate and of roots with direct drilling did not restrict phosphate uptake by the crop, despite the dry summer. The results are discussed in relation to factors contributing to differences in the distribution of nutrients and roots in land receiving contrasting cultivations, and possible consequences for crop growth are indicated.
The accumulation of volatile substances in a large modern potato store
Authors: Filmer Anthony A. E. , Land Derek G.
Published: November 2006

An apparatus for sampling and trapping the air in potato stores was developed and used to study the accumulation of volatile substances in a modern large store over a season. Isopropyl‐N‐(3‐chlorophenyl) carbamate (CIPC, chlorpropham), together with two isomers of tetrachlorobenzene, was present at all times after its application as a sprout suppressant, although the concentration fell with time. None of the known volatile substances associated with potatoes nor metabolites of isopropyl‐N‐(3‐chlorophenyl) carbamate was detected. 2,3,4,6‐Tetrachloroanisole and pentachloroanisole were present at all times even before the store was filled, but did not reach levels at which taint occurred in the processed products. Eight commercial samples of isopropyl‐N‐(3‐chlorophenyl) carbamate were analysed and the only major variation found was the presence of isopropyl‐N‐phenyl carbamate (IPC, propham) in two formulations.
Effects of N‐fertilisation on amino acid composition and nutritive value of spinach, kale, cauliflower and potatoes
Authors: Eppendorfer Wilfried H.
Published: November 2006

Spinach, kale, cauliflower and potatoes were grown in pots at differing levels of nitrogen fertilisation. Increased nitrogen in the soil led to increased total‐N and nitrate contents but decreased amino acid concentrations (g/16 g total‐N) in spinach and kale. Similar treatments on cauliflower and potatoes also increased the total‐N but the nitrate concentrations were negligible; amino acid concentrations in the crude protein decreased except for aspartic and glutamic acids in potatoes. The essential amino acid indices and chemical scores decreased with increasing N‐content in all crops. When compared with egg protein, methionine and cystine were generally the most limiting amino acids. At low N‐levels, methionine and cystine were generally above the FAO amino acid reference limits. In rat feeding experiments, increased total‐N concentrations were associated with higher true digestibilities of the crude protein in all four crops, and the biological values tended to increase. Addition of synthetic methionine to potatoes increased their biological values by 35 and 12% at low and high N‐levels. Increasing total‐N contents increased the net crude protein utilisation in the four crops. Increased N‐applications decreased the nutritive value of the crude protein when judged on the basis of amino acid determinations, but the opposite conclusion was reached from the results of the feeding experiments.
The potential of sunflower as a crop for ensilage
Authors: Alun Edwards R. , Harper Frederick , Henderson Annie R. , Donaldson Elizabeth
Published: November 2006

The chemical composition and nutritive value of sunflower, cv. Armavirec, was examined at 12 stages of growth. Maximum yield of dry matter (18.2 t ha−1) occurred at the dough seed stage. Ether extract showed a five‐fold increase with the development of the seed. This increase was reflected in the gross energy value which was maximal at 19.1 MJ kg−1 dry matter at the dough seed stage. In‐vitro organic matter digestibility was highest at the onset of flowering when the estimated metabolisable energy value was 10.5 MJ kg−1 dry matter. Throughout the sampling period the calcium to phosphorus ratios varied from 3.9‐5.9:1, an imbalance which would have to be redressed on diets based largely on sunflowers. Fresh and wilted sunflowers were successfully ensiled at the flowering stage, without the use of additives. pH values of the resulting silages were 3.86 and 4.01. The silages were each fed to six cross‐bred wethers and voluntary dry matter intakes were 23.9 and 26.5 g kgW−1 for the fresh and wilted silages respectively. For the fresh silage, intakes of digestible organic matter and digestible nitrogen were 612 and 13.6 g day−1 compared with 684 and 16.7 g day−1 for the wilted silage. Nitrogen retention increased with increase in silage dry matter. The optimum time of cutting for yield of nutrients is at the milky ripe stage. The composition of the crop at this stage should facilitate a satisfactory preservation by ensiling. The crop provides a high yield of dry matter over about 10 weeks in late summer and could provide a valuable standby forage crop for grass in dry areas.
The stability of wheat starch lipids in untreated and chlorine‐treated cake flours
Authors: Morrison William R.
Published: November 2006

Untreated flour and flour treated with chlorine (2.2 g Cl2 kg‐1) were stored in air at 25°C for 4 months. Starch samples prepared from the original flours were stored in air at 25°C for 4 months. Starch samples were also prepared from the fresh flours (control starches) and from the stored flours. Some of the starches from the stored flours were subsequently held at 70°C for 1 month. Starch lipids were not affected by flour chlorine treatment, or by storage at 25°C. There was slight hydrolysis of starch lysophospholipids at 70°C, but negligible autoxidation of unsaturated fatty acids in the total starch lipids. There was appreciable hydrolysis of non‐starch lipids in the untreated stored flour, but no detectable autoxidation of unsaturated fatty acids. Chlorine treatment of flour caused an immediate loss of approximately half of the oleic, linoleic and linolenic acids in all the non‐starch lipids which were examined. There was no further change in the fatty acid composition of the non‐starch lipids when the treated flour was stored, but lipid hydrolysis was substantially reduced compared with the untreated stored flour.
The characterisation and measurement of Hbr‐reacting acids in Mucuna pruriens and Urena lobata seed oils
Authors: Ahmad Moghis U. , Husain Syed K. , Osman Sheikh M.
Published: November 2006

Seed oils of Mucuna pruriens (Leguminosae) and Urena lobata (Malvaceae) were found to contain HBr‐reacting acids to the extent of 1.3 and 10.8% respectively. Acetylation of the M. pruriens seed oil, followed by saponification and separation of the acids, gave 12,13‐dihydroxyoleic acid. From this and other evidence it is concluded that 12,13‐epoxyoleic (vernolic) acid is present as a constituent of the glycerides. On the other hand, the cyclopropenoid material in U. lobata oil was characterised as a mixture of malvalic (4.8%) and sterculic (6%) acids by the gas‐liquid chromatography (g.l.c.) of the silver nitrate‐methanol treated methyl esters. Seed oils of Vernonia anthelmintica and Sterculia foetida were used as reference standards.
Studies on 2,4,6‐trinitrobenzenesulphonic acid‐reactive lysine using cowpeas (vigna unguiculata (L) walp), maize (zea mays) and DL‐lysine
Authors: Tella Ayoni F. , Ashton Walter M.
Published: November 2006

The conditions for the coupling reaction between 2,4,6‐trinitrobenzenesulphonic acid (TNBS) and the free ϵ‐amino group of lysine, and the conditions for the hydrolysis of the resulting trinitrophenylated compound, were investigated using cowpeas (Vigna unguiculata), maize (Zea mays) and DL‐lysine. The use of DL‐lysine as a standard in place of ϵ‐TNP‐lysine HCl.H2O, was also investigated. The optimum temperature, reaction time and hydrolysis time were found to be 30°C, 2 h and 2 h respectively for cowpeas and maize. The results obtained from reacting DL‐lysine with TNBS showed that using DL‐lysine as a reference standard is likely to overestimate TNBS‐reactive lysine.
The effect of soaking, germination and cooking on the protein quality of mash beans (Phaseolus mungo)
Authors: Khan Mohammed Akmal , Ghafoor Abdul
Published: November 2006

The protein quality of mash beans (Phaseolus mungo) as affected by soaking, germination and cooking was determined at the 10% dietary protein level using weanling rats. Gains in body weight were 11.5 g for raw beans, 68.5 g for soaked‐cooked and 33.0 g for germinated‐cooked beans. The protein efficiency ratio values were 0.4, 1.9 and 1.1 for raw beans, soaked‐cooked and germinated‐cooked beans respectively. Net protein utilisation was improved from 44% for raw beans to 58% after soaking and cooking, but reduced to 47% after germinating and cooking. These changes were entirely accounted for by changes in digestibility, 72, 90 and 81% respectively, and biological values were unchanged at 61, 64 and 59 respectively.
The sensory evaluation of jonathan and delicious apples treated with the growth regulator ethephon
Authors: McBride Robert L. , Faragher John D.
Published: November 2006

Jonathan and Delicious apples were sprayed with the growth regulator Ethephon at concentrations of 250 and 500 parts 10−6. Fruits from each spray treatment were harvested sequentially in three stages, approximately 1, 2 and 3 weeks after treatment; then submitted to panels for sensory evaluation. Ethephon significantly enhanced hedonic scores for skin colour, flavour and general acceptability of Jonathan apples regardless of the harvest time, but had no significant effect on texture. The skin colour of Delicious apples was significantly improved by Ethephon application (regardless of harvest time) but there was no significant effect on flavour or general acceptability and texture was significantly impaired.
Release of nitrogen, sulphur, phosphorus, calcium, magnesium, potassium and sodium from four tropical hays during their digestion in nylon bags in the rumen
Authors: Playne Martin J. , Echevarría Mariano G. , Megarrity Robert G.
Published: November 2006

The rate of release of N, S, P, Ca, Mg, K and Na from four milled tropical hays in nylon bags in the rumen of cattle over a 168 h period were measured. The hays were: Medicago sativa, Stylosanthes humilis, Chloris barbata and Heteropogon contortus. Three ways were used to express results: (a)element as % of element initially present; (b) element as % of dry matter initially present, and (c) element as its concentration in residual dry matter. The proportions of elements removed during digestion were positively related to initial concentration of the elements in the hays, with the exception of P in C. barbata hay. High proportions of Mg and K were released within 48 h in all hays. Only about 60% of N, P and Ca initially present was removed even after 168 h in the rumen. Amounts of elements remaining became constant for each element after 48 h and were for N, 6.0; Ca, 3.0; K, 1.0; P, 0.7; Na, 0.7; S, 0.5 and Mg, 0.3 g element kg−1 DM initially present. Concentrations of elements in the residual dry matter after decreasing in the first 24 h, increased in the latter stages of digestion, even though cell wall digestion continued. The four hays released the seven elements differently. Generally, the elements in Medicago were most soluble and those in Heteropogon the least. However, the extent of solubilisation in Stylosanthes and in Chloris varied with the element concerned. In Heteropogon hay, which had low element concentrations initially, less than half of the N, S, P, Ca and Na were released even after 168 h digestion.
Chemicals to prevent the moulding of hay and other crops
Authors: Lord Kenneth A. , Lacey John
Published: November 2006

Fungi from hay, Paecilomyces varioti and species of the Asperigillus glaucus group tolerate and metabolise propionic acid. These may be inhibited in vitro by low concentrations (0.001‐3%) of 8‐hydroxyquinoline and some derivatives. Addition of 10% of these derivatives to propionic acid diminished by a factor of two the amount needed to prevent heating and moulding of hay and other crops, in laboratory and field tests.
Changes in the physicochemical properties of rice with aging
Authors: Swamy Yelandur M. Indudhara , Sowbhagya Chakrabhavi M. , Bhattacharya Kshirod R.
Published: November 2006

Seven varieties of rice belonging to dwarf indica, tall indica and japonica classes were stored as paddy as well as milled rice at 1‐3°C, room temperature (RT) and 37‐40°C in the dark and also at RT in the light for 3.5 years. Various physicochemical properties were measured in the samples at intervals. The aging process in rice appeared to be characterised by: (a) an increase in volume expansion and a steady decrease in solids loss upon cooking, (b) an initial increase followed by a steady decrease in the power of hydration (water uptake at 96 and 80°C, equilibrium moisture content), (c) probably a slow decrease in the solubility of the amylose and a slow increase in the gelatinisation temperature, (d) an initial increase followed by a steady decrease in paste viscosity and setback, and (e) a sharply decreasing viscograph breakdown. The process was retarded effectively by storage in the cold. Conversely, it was greatly hastened by storage at high temperature and to some extent by exposure to light. In addition, the process occurred much faster and/or to a greater extent in high‐amylose (total as well as insoluble) rather than in low‐amylose varieties, and to some extent in milled rice rather than in paddy.
The source of androgenic activity in the African wood Funtumia latifolia: A steroid hormone formed by the action of fusarium solani
Authors: Smith Anthony J. , Wells John W.
Published: November 2006

The wood of an African tree Funtumia latifolia had androgenic properties when mixed with diets fed to chicks. The androgenic principle has been identified tentatively as an hydroxyandrosta‐1,4‐dienedione but it is not identical with 12β‐hydroxyandrosta‐1,4‐diene‐3,17‐dione isolated previously from the leaves of a Halorrhena species in Cameroun or as a microbial metabolite of deoxycholic acid. The androgen is formed by metabolism of the steroidal alkaloids in F. latifolia by the saprophytic fungus Fusarium solani.
The extraction of the enzyme degrading the limonin precursor in citrus albedo
Authors: Nicol Kenneth J. , Chandler Bruce V.
Published: November 2006

Optimum conditions for extracting the enzyme degrading the limonin precursor in citrus albedo involved treatment of the macerated albedo with a commercial pectic enzyme. The release of the enzyme from the cells of the albedo was accompanied by a considerable loss of stability, and the instability of the enzyme once dissociated from the albedo cells, together with its low activity in a highly pectinous source, accounts for the failure of previous attempts at its extraction. A method for proximate assay of enzyme actiyity was developed to monitor the extraction process and to compare the concentrations of enzyme activity in various albedo samples.
trans‐4,5‐epoxyhept‐trans‐2‐enal the major volatile compound formed by the copper and α‐tocopherol induced oxidation of butterfat
Authors: Swoboda Peter A. T. , Peers Kenneth E.
Published: November 2006

The volatile compound produced in greatest yield from the aerobic incubation at 35°C for 35 h of a mixture of butterfat, cupric palmitate and α‐tocopherol was characterised by chromatography and spectroscopy. The same compound was also isolated from a similar reaction mixture containing cod‐liver oil instead of butterfat. The compound was identified as trans‐4,5‐epoxyhept‐trans‐2‐enal and was found to have the same properties as that synthesised by the epoxidation of hepta‐trans‐2,trans‐4‐dienal. Volatile epoxyalkenals of this type have not been previously identified as products from lipid oxidation.
A consumer test of bull vs steer beef
Authors: Baron Peter , Lesser David , Robertson Ian , Parry Doreen , Lowman Basil , Scott Neil , Prescott John
Published: November 2006

Previous studies of the acceptability of bull beef have relied on laboratory panel or mechanical tests. This study extends the assessment to a consumer panel who cooked and ate the conventionally prepared steaks in their own homes. The test showed consumers to distinguish bull steaks as leaner than steer steaks but not to discriminate on overall appearance. When it came to eating, however, bull steaks were judged to take longer to brown and be less satisfactory in terms of flavour, juiciness, tenderness and overall eating quality. On tenderness 11% of the sample marked the bull steaks as ‚well below average’︁. These results are sufficiently clear to suggest the need for a test of their commercial impact.
Effect of procedures for the reduction of the nucleic acid content of SCP on the DNA content of Saccharomyces cerevisiae
Authors: Trevelyan William E.
Published: November 2006

Autolysis of a suspension of baker's yeast, triggered by heat shock, organic solvents or drying/rehydration, had previously been found to degrade yeast RNA to diffusible products, leaving a resistant, cell‐bound fraction characterised by a high adenine: guanine ratio, which it was suggested might be DNA. Analysis for DNA by the diphenylamine reaction now shows that even when autolysis (following heat shock) is prolonged to the point at which the cells lose 42% of dry matter and half their protein content, no DNA leaves the cells. Overnight treatment of freeze‐dried yeast preparations with In perchloric acid at room temperature extracts the purines of DNA in the free form, and estimations of DNA content based on this agree with the results of the diphenylamine method in the case of autolysed or alkaline salt‐extracted yeast preparations, which have a low RNA content. With untreated yeast, which contains 20 times as much RNA as it does DNA, the picture is complicated by a slow, but significant depurination of RNA by 1N perchloric acid. The implications of this, and other findings, are considered in respect of analytical procedures for yeast DNA and RNA content.
A routine method for predicting the formononetin content of red clover
Authors: Gosden Anthony F. , Jones Raymond
Published: November 2006

A simplified technique is described in which the fluorescence of a crude extract of red clover is used to predict the formononetin content. A high correlation (r≥0.95) was found between the proposed method and formononetin determined chromatographically.
Comparison of a short method for Kjeldahl digestion using a trace of selenium as catalyst, with other methods
Authors: Marshall Claire M. , Walker Ann F.
Published: November 2006

A short digestion method for Kjeldahl nitrogen determination, using a trace of selenium as catalyst and described in this paper, gives results comparable to the American Association of Cereal Chemists (1976) method using mercuric oxide catalyst, for all compounds tested except for nicotinic acid. However, nicotinic acid is a minor component of food materials and it is not normally assayed by the Kjeldahl method. Selenium, like mercury, is known to be toxic7 but mercury ranks more highly than selenium as an environmental problem.
The properties of trona and its effect on the cooking time of cowpeas
Authors: Ankrah Emmanuel K. , Dovlo Florence E.
Published: November 2006

Trona (Urao) popularly known in Ghana as kawe is used for medicinal and tenderiser purposes (especially in reducing the cooking time of cowpea). The type of kawe found in Ghana contained predominantly 25.0% sodium with small amounts of other metals. Cooking cowpeas in the presence of kawe reduced the cooking time from 75 to 50 min which represents a saving of time and fuel to the cooker.
Gel formation in acidified aqueous suspensions of cereal flours
Authors: Jennings Allen C.
Published: November 2006

The amounts of gel formed when wheat flours are suspended in 1m acetic acid or in phenol‐acetic acid‐water (1:1:1, w/v/v) are highly correlated with the total nitrogen contents and the Zeleny sedimentation values of the flours. It is concluded that the Zeleny sedimentation test depends on the formation of this gel. Gel formation in acidified aqueous suspensions is markedly affected by the ionic strength and pH of the suspending medium, but not by non‐polar molecules or reagents that react specifically with sulphydryl groups or disulphide bonds. The gel is readily dispersed by ultrasonic treatment and gel formation is prevented completely by the amounts of sodium chloride added to dough during breadmaking.
The physical properties of modified palm oil
Authors: Okiy Dere A. , Wright Winifred B. , Berger Kurt G. , Morton Ian D.
Published: November 2006

Palm oil has been treated by partial lipase hydrolysis and by interesterification with excess glycerol and the effects on the chemical and physical properties have been investigated. Lipase hydrolysis preferentially removes unsaturated acids and the neutral glycerides remaining after removal of the free fatty acids therefore have an increased solids content at 20°C. Both differential scanning calorimetry (d.s.c.) and X‐ray examination show that the crystalline phases present above 20°C are more heterogeneous after lipase treatment. Interesterification results in a mixture of tri‐ and diglycerides with an increased solids content at 20°C and a marked tendency to form β phase crystals. Some potential practical applications are discussed.
Effect of baking on the nutritive value of Pakistani bread
Authors: Khan Mohammed Akmal , Eggum BjøRn O.
Published: November 2006

The nutritive value of Pakistani breads prepared from wheat, maize, rice, barley, millet, triticale and sorghum were measured chemically, by proximate, fatty acid and amino acid analyses and biologically in N‐balance experiments with growing rats. Yeast was not used in the preparation of doughs. The levels of lysine, threonine and tryptophan were in several cases negatively affected by the baking procedure. According to FAO 1973 scoring pattern, lysine and threonine were found to be the first and second limiting amino acids in most of the breads. Methionine does not appear to be the third limiting amino acid. Net protein utilisation was negatively affected by baking only in the case of barley (6%) and maize (9%) whereas the biological value was improved in triticale (8%) and sorghum (6%) compared to the corresponding unprocessed samples. The baking procedure did not affect the digestible energy in triticale. Net dietary protein calories percentage values indicate that the cereal breads, except sorghum, had values higher than 5%.
An investigation of lignin extraction from dietary fibre using acetyl bromide
Authors: Robertson James A. , Eastwood Martin A. , Yeoman Michael M.
Published: November 2006

Acetyl bromide is a suitable reagent for the extraction of lignins from woody material and grasses but lignins present in vegetables do not give the expected absorbance spectrum. Treatment of the vegetable fibre with either organic solvents or dilute acid or the removal of protein and hemicellulose does not alter the absorbance spectrum of lignins present in vegetables. All methods used for lignin extraction are quantitatively consistent and show only a trace of lignin to be present in vegetable fibre.
Soil conditioners for stabilising trench backfill in an unstable loam soil of low permeability
Authors: Goossens Frans , Dierickx Willy , Gabriels Donald , de Boodt Marcel
Published: November 2006

Laboratory experiments were carried out to evaluate different soil conditioners for stabilising a loam soil, the aim being to increase the structural stability and the permeability of the backfill of drain trenches. Soil samples previously treated with different concentrations of polymer solutions or emulsions were dried to different moisture contents and packed in cylinders to determine the changes in water permeability. Identical soil samples were subjected to wet‐sieving tests for different lengths of time. Loam soil samples treated with emulsions need to be air‐dried to make them stable and highly permeable. At higher moisture contents the emulsions become ineffective because of the lack of coagulation between the soil particles. Polymer solutions are effective with regard to soil stability and water permeability even in situations where the soil remains wet. There is a fair agreement between the results of the wet‐sieving test and those of the permeability test on loam soil samples. Those two tests were considered as reflecting the behaviour of the soil in a backfilled drain trench.
Cation‐exchange capacity of clonal tea roots and its implications on fertiliser responses
Authors: Chamuah Ghanashyam S. , Dey Sunil K.
Published: November 2006

Fifteen genetically different tea clones showed no variation in their root cationexchange capacity (CEC) values when assessment was made separately on white (including creamy white and cream) and brown (including creamy brown and reddishbrown) portions of roots. But CEC values determined on the whole root system of the same clones were significantly different. This was true for plants varying in age from 8 to 18 months. Clones of Assam types gave lower root CEC values throughout the experimental period than China types, while clones of the Southern form of tea (Cambod) gave high root CEC values initially, which dropped rapidly as the plants became older. Root CEC of different clones was found to be negatively correlated with the brown: white root ratio and with the K: √Ca ratio of the plant tops. Ageing of plants decreased root CEC by increasing the proportion of brown roots, as a result of which the K: √Ca ratio also decreased with age.
An improved method based on gas chromatography for determining the amino acid composition of commercially produced fish‐meal
Authors: Moodie Iain M. , Collier Grant S. , Burger Jennifer A. , Werb Barbara C.
Published: November 2006

The development and refinement of a technique, based on gas chromatography, for the amino acid analysis of fish‐meal are described. Emphasis is placed on streamlining the procedure to facilitate handling samples on a routine basis. Experiments are described from which data are assessed for precision. Results from these experiments confirm that the hydrolysis step contributes significantly to the reduced precision encountered in this type of analysis.
Crufomate residues in milk and milk products following treatment of dairy cows for warble‐fly
Authors: O'Keeffe Michael , Eades Joseph F. , Strickland Kenneth L. , Harrington Dermot
Published: November 2006

A group of ten dairy cows were treated for warble‐fly with the organophosphorus pesticide, crufomate. The persistence of crufomate in the milk of the cows after treatment was determined by gas‐liquid chromatography with a phosphorus‐specific thermionic detector. The mean crufomate concentration in milk dropped below the Codex maximum limit of 0.05 mg kg−1 within 24 h of treatment. Crufomate was found to accumulate in the fat fraction of milk, giving rise to a higher concentration of crufomate in milk products, relative to the concentration in whole milk.
The effects of soil management systems on the chemical composition and quality of golden delicious and cox's orange pippin apples—a follow‐up study
Authors: Gormley T. Ronan , Robinson David W. , O'Kennedy Niall D.
Published: November 2006

Tests on Golden Delicious and Cox's Orange Pippin apples, evaluated in five and three seasons, respectively, between 1972 and 1980, indicated that method of soil management was still influencing fruit quality 15 years after commencement of the experiment, although to a lesser extent than in the earlier years. In 1973, the soluble solids content, skin colour and yield values of Golden Delicious differed between treatments but no differences were observed for fruit firmness in any of the five seasons when fruit were tested. Acidity values differed in 1972, 1973 and 1980. Overall herbicides gave the highest yields in 1973 and 1975 and the lowest levels of soluble solids. The yield of Cox's Orange Pippin fruit varied considerably between seasons; yields between treatments within seasons were only different in 1975. Correlation coefficients between yield and soluble solids were negative and ranged from ‐0.51 to ‐0.68.
Pollution of agricultural karstic soils by lead from automobile exhaust gases
Authors: Favretto Luciana Gabrielli , Marletta Giuliana Pertoldi , Favretto Luciano
Published: November 2006

Pollution of terra rossa soils from the Karst near Trieste by atmospheric lead from automobile exhaust gases is considered as a function of the distance from the source, an isolated straight road. The asymptotic decrease in lead concentration in soil with the distance on both sides of the road is empirically described by means of an intrinsically linear exponential function. The parameters (asymptote and curvature) of the function are first evaluated by linear regression with the linearised function, and then determined by a nonlinear regression program. The application of this model function allows an evaluation of the asymptotic lead concentration. Statistical analysis shows that fitting improves if lead concentration is referred to on a CaCO3‐free basis, because the calcareous grains from terra rossa < 1 mm‐samples contain only traces (< 2 μg −1) of metal. The effect of prevailing winds is also discussed.
Headspace analysis of laboratory samples of potato tubers treated with 1,4‐dimethylnaphthalene, carvone, pulegone and citral
Authors: Beveridge James L. , Dalziel John , Duncan Henry J.
Published: November 2006

1,4‐Dimethylnaphthalene, carvone [2‐methyl‐5‐(1‐methylethenyl)‐2‐cyclohexene‐1‐one], pulegone [5‐methyl‐2‐(1‐methylethylidene) cyclohexanone] and citral (3,7‐dimethyl‐2,6‐octadienal) were applied as liquids on an alumina solid carrier to samples of potato tubers stored in boxes. The headspace concentrations of the chemicals were related to the degree of growth regulation found in this and earlier solid carrier application experiments and were compared to studies using constant vapour concentration applications which had been conducted previously by other workers. Headspace concentrations of all four chemicals increased with increasing application rates indicating non‐ideal behaviour. Pulegone (100 mg kg−1), carvone (100 mg kg−1) and citral (100 and 500 mg kg−1) did not prevent sprouting. Headspace concentrations of these treatments were less than the constant vapour concentrations previously shown to inhibit sprouting. Pulegone (500 mg kg−1) and carvone (500 mg kg−1) successfully inhibited sprouting. Initial headspace concentrations of these treatments were within the constant vapour concentration range previously shown to prevent sprouting. Headspace concentrations of all four chemicals decreased during the 14‐week treatment period. Headspace concentrations of 1,4‐dimethylnaphthalene, when applied at the recommended solid carrier application rate of 100 mg kg−1 were within the constant vapour concentration range previously shown to prevent sprouting. Headspace concentrations of 1,4‐dimethylnaphthalene between 3 and 6 mg m3 would be necessary if the chemical were to be successfully applied as a vapour. For these experiments a gas chromatographic (g.c.) analytical method using porous polymer adsorbents was developed. The method was rapid, with a coefficient of variation of 5%.
Effects of the application of fertilisers and trace elements on the cobalt content of herbage cut for conservation
Authors: Reith James W. S. , Burridge John C. , Berrow Michael L. , Caldwell Kynoch S.
Published: November 2006

The effects of the application of fertilisers, especially N and trace elements, on the content of Co in mixed grassland herbage and its main constituent species, have been studied. Data have been obtained from field experiments on three mineral soils and on a deep acid peat. The herbage was cut at the silage stage of growth three or four times a year for at least three successive years. Without added Co, N applications increased Co content in herbage on peat but reduced it on mineral soils mainly by eliminating clover which had a higher Co content than grasses. Applying 0.5 kg ha−1 Co as cobalt sulphate increased herbage Co content, the increase being greater on peat than on mineral soils. These increased levels were unaffected by N applications on mineral soils but were further increased by applied N on peat. The number of years during which the Co additions were effective in producing herbage containing at least 0.1 mg Co kg−1 dry matter varied on the different soils, ranging from barely three years on one mineral soil to over five years on peat. Without added Co the last cuts in October usually had the highest Co content and the first cuts in June the lowest. With added Co, the seasonal effects were more variable, but the Co content in the herbage frequently decreased from the first to the last cuts.
The influence of 2,4‐dichlorophenoxyacetic acid on lactic acid bacteria
Authors: Libudzisz Z. , Kirkwood R. C.
Published: November 2006

The effect of 2,4‐dichlorophenoxyacetic acid (2,4‐D) (4 × 10−5M‐4 × 10−3M) on the growth and physiological activity of Streptococcus lactis subsp. diacetylactis and Lactobacillus casei has been investigated when cultivated in milk and lactose‐peptone media. The concentrations of 2,4‐D applied in milk did not cause complete growth inhibition of any of the strains. The degree of inhibition was dependent upon the bacterium species and the herbicide dose. Growth of the tolerant strain—L. casei W‐10—was reduced by about 40% (in the presence of 4 × 10−3M 2,4‐D), whereas the the level of lactic acid production remained almost unchanged. Under the same conditions, growth of the sensitive strain S. lactis subsp. diacetylactis 239 was reduced by almost 25 times and lactic acid production inhibited by about 40% in comparison with the controls. Cultivation of S. lactis subsp. diacetylactis 239 in lactose‐peptone medium with 2 × 10−3M 2,4‐D was characterised by a lengthened lag‐phase, lengthened generation time (3 times) and an increased rate of herbicide metabolism. In addition, selective or mutative action of 2,4‐D has been shown. Herbicide treatment inhibited the cells of c.f.u. producing the least acid and enhanced the contribution of the active ones. Cells of c.f.u. with activities not found in the control population have also been revealed. Both species of bacteria were capable of metabolism of 2,4‐D to 2,4‐dichlorophenol.
The effects of spoilage on the dielectric properties of frozen fish
Authors: Kent Michael
Published: November 2006

Using a time‐domain technique to obtain low frequency dielectric data the effects of spoilage on certain dielectric properties of frozen cod (Gadus morhua), haddock (Melanogrammus aeglefinus) and lemon sole (Microstomus kitt) have been measured at − 78.5°C in the frequency range 0.025–10 kHz. The spoilage varied with the period of storage in ice prior to freezing. The measurements revealed a relaxation, the frequency of which in cod and haddock depended on pre‐freezing quality of the fish. The relationship is discussed between this dependence and various other parameters and the relaxation is tentatively identified as that of a Maxwell‐Wagner mechanism.
Skull shape in relation to carcass fatness in pigs
Authors: Gregory Neville G. , Whelehan Oliver P.
Published: November 2006

The relationships between skull shape and carcass fatness were examined in sixty pigs using seventeen linear skull measurements and ten measurements of carcass fat weight. The skull measurements were combined using the multivariate statistical technique of principal components analysis to provide an index of the most variable feature of skull shape. The principal shape component was found to contrast long and narrow skulls with short and broad ones. Correlations showed that a long narrow skull, which is recognised as a late developing feature in the overall growth of the pig's skull, was associated with a fatter carcass. It is suggested that late developing features in bone growth may have value in assessing the overall development of late developing tissues such as fat.
Lipid oxidation in salted‐dried fish: The effect of temperature and light on the rate of oxidation of a fish oil
Authors: Davis Louise , Goodwin Lisa , Smith Gillian , Hole Michael
Published: November 2006

In relation to studies of lipid oxidation during the processing and storage of salted sun‐dried fish, the measurement of the initial rate of oxygen uptake has been studied on a model system consisting of a highly polyunsaturated fish oil. This parameter has been used for assessing the effects of temperature and light conditions on the model system and has been compared to changes in the peroxide value and the polyene index. Assessment of oxygen uptake using a Gilson respirometer was found to give a clearer indication than other methods of assessment of the effect of different conditions on fish oil oxidation. At 30°C the initial rate of oxygen uptake increased from 0‐103 μl O2, g−1 miir−1 to 0‐158 μl O2, g−1 min−1 with a change in light conditions from dark to photosynthesis light. At 40°C, the rate of oxygen uptake was fester than at 30 °C, and the effect of light was more pronounced, giving values of 0.188 μl O2, g−1 min−1 and 0.483 μ O2, g−1 min−1, for dark and photosynthesis light, respectively. The observed results for the measurement of the initial rate of oxygen uptake suggest its use as a sensitive and reliable method for the investigation of the contribution of the many components in salted sun‐dried fish towards the rate of oxidation and subsequent rancidity.
Solubilisation of non‐starch polysaccharides from oil‐seed meals by polysaccharide‐degrading enzymes
Authors: Düsterhöft E‐M. , Bonte A. W. , Voragen A. G. J.
Published: November 2006

The solubilisation of non‐starch polysaccharides from cell wall materials (CWM) of palm‐kernel and sunflower meals was studied using multi‐component polysaccharidase preparations or fractions thereof. In sunflower CWM, the degradability of pectic compounds and mannose‐containing polysaccharides was highest, as estimated from 40 to 70% solubilisation of their constituent monosaccharides arabinose, galactose, galacturonic acid, rhamnose and mannose. Dimers and monomers were produced as major neutral and acidic end‐products. Mannans in palm‐kernel CWM were hydrolysed to about 20–50%, depending on enzyme composition, with the monomer and dimer of mannose as major endproducts. In both materials, xylans, or other xylose‐containing polymers, were most resistant to enzymic hydrolysis. The results indicate the preferential solubilisation of parenchyma tissues from the seed in sunflower meal and the endosperm in palm‐kernel meal, and the resistance of sunflower hull and palm‐kernel endocarp to enzymic attack. The concentrations of notably cellulolytic, mannanolytic and arabinolytic activities clearly determined the extent to which the corresponding constituents were solubilised.
Effects of processing and storage on some chemical characteristics and lipid composition of a ghanaian fermented fish product
Authors: Yankah Vivienne Vera , Ohshima Toshiaki , Koizumi Chiaki
Published: November 2006

To evaluate the effectiveness of the traditional method of processing in preservation of the final product, the changes in composition of lipids, free amino acids and organic acids of ‘momoni’, a Ghanaian fermented fish product, were investigated using Japanese jack mackerel (Trachurus japonicus) which is similar to African jack mackerel (Caranx hippos). The moisture content decreased drastically from 751 to 505 g kg−1 after fermentation for 3 days, and then remained almost constant during subsequent storage. Changes in pH were minimal although a gradual decrease was observed from 6·2 in the raw material to 5·9 after 2 months storage. Salt accumulation due to the salting process increased up to 325 g kg−1 but remained almost unchanged during subsequent storage. Volatile basic nitrogens (VBN) increased to 0·8 g kg−1 on a salt‐free dry matter basis, after 2 months storage. Most free amino acids, except histidine which was present in the highest concentration in the samples, increased during processing and subsequent storage. However, no detectable amount of histamine was formed after 2 months storage. Lactic acid, the most prominent organic acid (3·12 g kg−1 salt‐free dry matter) in the raw materials, decreased during processing and subsequent storage. Diphosphatidylglycerol, free fatty acids, and lysophosphatidylcholine increased appreciably. Processing resulted in depletion of sphingomyelin, phosphatidylserine and phosphatidylinositol with decreases in triglycerides, cholesterol, phosphatidylethanolamine and phosphatidylcholine. The proportion of the extracted total lipids present as polyunsaturated fatty acids decreased and this was accompanied by increases in the proportions of saturated fatty acids, indicating a high degree of oxidation. Peroxide value and thiobarbituric acid value increased on fermentation, confirming the observed oxidation, but decreased during storage. In conclusion, although oxidation was extensive, following hygienic and good manufacturing practices, this simple method could prevent spoilage taking place in fish if good‐quality raw materials are used.
The performance of ELISA and dot‐blot methods for the detection of crab flesh in heated and sterilized surimi‐based products
Authors: Verrez‐Bagnis Véronique , Escriche‐Roberto Isabel
Published: November 2006

Polyclonal anti‐lobster arginine kinase antiserum was used as a probe to test for the presence of crab flesh (invertebrate tissues) in surimi‐based products. Arginine kinase is a cytoplasmic enzyme present in many invertebrates and is absent from vertebrates. Antibodies against lobster arginine kinase interacted strongly with snow crab but they gave only a low response in molluscs such as limpet, squid and scallop. Surimi (washed fish mince) exhibited a slight residual immunobinding response. Arginine kinase could easily be detected in crab‐supplemented surimi preparations with a correlation between the level of crab added to surimi and the level of immunological response. Using direct enzyme‐linked immunosorbent assay and an immunodot procedure, the results showed that an addition of 10–25 g of crab flesh per kg surimi‐based products could be detected even after a high sterilization process.
Postharvest changes in ammonium, amino acids and enzymes of amino acid metabolism in asparagus spear tips
Authors: Hurst Paul L. , Clark Christopher J.
Published: November 2006

Harvested asparagus (Asparagus officinalis L) spears accumulate ammonium and amino acids in their tips during storage at ambient temperatures. To further investigate these phenomena the authors held spears at 20°C in the dark after harvest and examined several parameters of amino acid metabolism in the tips. Soluble protein content declined faster than total protein over the 5‐day storage period. Protein loss was accompanied by an increase in total free amino acids with asparagine showing the most dramatic increase. A pronounced accumulation of ammonium occurred, starting after 3 days. The activities of glutamine synthetase (EC 6.3.1.2) and aspartate and alanine aminotransferases (EC 2.6.1.1 and EC 2.6.1.2, respectively) declined slightly whereas glutamate dehydrogenase (EC 1.4.1.2) activity almost doubled over 5 days. Phenylalanine ammonia lyase (EC 4.3.1.5) activity declined rapidly during the first 2 days and then partially recovered. Asparagine synthetase (EC 6.3.1.1), asparagine aminotransferase (EC 2.6.1.14), asparaginase (EC 3.5.1.1) and glutaminase (EC 3.5.1.2) activities were not detectable at any time during the storage period. Ammonium accumulation could be caused by increased glutamate dehydrogenase activity coupled with a shortage of aspartate.
Determination of phenolic acids in plant cell walls by microwave digestion
Authors: Provan Gordon J , Scobbie Lorraine , Chesson Andrew
Published: November 2006

Microwave digestion (750 W for 90 s) with 4 M NaOH was used to release esterified and etherified hydroxycinnamic acids from cell walls of maize (Zea mays L), wheat (Triticum aestivum L), barley (Hordeum vulgare L) and oilseed rape (Brassica napus L) stems. Subtraction of values for saponifiable phenolic acids obtained after treatment with I M NaOH at room temperature from digest results provided a measure of β‐ether linked units. These were exclusively (E + Z)‐ferulic acid in the cereal straws. Only trace amounts of ether‐ and ester‐linked hydroxycinnamic acids were released from the dicotyledon, ripe straw. Microwave digestion was shown to be an order of magnitude more effective than dioxane‐HCl at liberating β‐ether bound phenolic acids and as effective, but substantially quicker, than previously described high‐temperature alkaline digestions.