bluuebunny/crossref_metadata_2025_split huggingface dataset:
Protein denaturation in frozen fish. VIII.—The temperature of maximum denaturation in cod
Authors: Love R. M. , Elerian M. K. 
Published: November 2006

AbstractDeterminations of cell fragility were performed on cod muscle frozen at −29° and then stored at −0.5° to −3.5°, at half degree intervals. The rate of denaturation was found to be maximal at a temperature close to −1.5°. Fresh tissue supercooled to the same temperature was not denatured.
Rapid method for the determination of cation‐exchange capacity of calcareous and non‐calcareous soils
Authors: Bascomb C. L. 
Published: November 2006

Abstract“Compulsive” exchange takes place between a barium‐soil and magnesium sulphate solution because Ba2+ ions are removed from solution by precipitation of barium sulphate. This phenomenon provides a basis for the very convenient routine method for cation‐exchange capacity determination in soils described here. An EDTA titration is used to measure the amount of magnesium exchanged from a standard solution by a Ba‐soil, which enables the cation‐exchange capacity to be calculated. Advantages of the method are its speed and that the sample does not have to be washed exhaustively, so avoiding possible hydrolysis. It compares favourably with standard A.O.A.C. procedure and is much more widely applicable. Soils rich in organic matter, e.g., peats, or with much calcium carbonate, can be handled without difficulty.
Non‐enzymic browning of lemon juice
Authors: Clegg K. Mary 
Published: November 2006

AbstractThe effect of various treatments on the non‐enzymic browning of lemon juice and model systems under aerobic conditions has been studied. Because of the high acidity (pH 2.5) of this product, it was unlikely that browning was due to sugar‐amine condensation and the results showed that ascorbic acid was the main precursor. Browning of lemon juice and model systems was proportional to the level of ascorbic acid; the presence of amino‐acids in model systems increased the intensity of browning.The investigation showed that the degree of non‐enzymic browning was influenced by the pH value of the product and was maximal at pH 4.5. Model systems demonstrated that ascorbic acid exhibited maximal browning at this pH value in the presence of citric acid and the part played by organic acids is considered to be important. There was evidence that although furfural was formed in the course of browning it was not an active compound in the development of coloured complexes.
An assessment of the quality of canned Northern Bluefin tuna Kishinoella tonggol
Authors: Prater A. R. , Montgomery W. A. 
Published: November 2006

AbstractThe relative acceptabilities of canned packs prepared from three species of tuna, namely, Northern Bluefin, Southern Bluefin and Yellowfin, have been compared by an analytical taste panel. The packs, prepared from fish of known history, were compared after ageing for 1 and after 6 months.The results showed that packs from all three species of tuna were readily acceptable. There was no evidence to support the belief that Northern Bluefin is inferior in quality to Southern Bluefin, the species of tuna used almost exclusively in commercial packs in Australia. The quality of the canned product was not improved by prolonging the ageing period to 6 months.Volatile constituents of the three species of fish were also compared by gas‐liquid chromatography of vapours from packs aged for 6 months at room temperature. The aroma profiles gave a typical and identical pattern of peaks for the three species of fish examined, thus supporting the conclusion drawn from the taste panel assessments.
Nitrogen fractions and soluble carbohydrates in italian ryegrass. I—Effects of soil temperature, form and level of nitrogen
Authors: Nowakowski T. Z. , Cunningham R. K. , Nielsen K. F. 
Published: November 2006

AbstractIn a glasshouse experiment Italian ryegrass S 22 grown for 9 weeks during October‐December in clay loam at three soil temperatures II°, 19.5° and 28° was given 6 levels of N (0—500 p.p.m.) as NH4+‐N or NO3−‐N. Tops grew best at 19.5° and with NO3−‐N yields were greatest at 100 p.p.m. and with NH4+‐N at 200 p.p.m. Increasing NO3+‐N above 200 p.p.m. greatly decreased growth but increasing NH4+‐N did not. At 100 p.p.m., NO3−‐N gave better yields than NH4+‐N but at 200 or more p.p.m. the reverse was true. Total‐N, total soluble‐N and nitrate‐N were much more, and protein‐N, amide‐N (particularly asparagine) and α‐amino‐N much less in grass given NO3−‐N than in grass supplied with NH4+‐N. These differences increased with increasing amounts of applied N. Increasing soil temperature considerably increased the total soluble‐N and decreased the protein‐N irrespective of the form of N added. With all treatments, plants contained very little carbohydrate; at 11 ° soluble carbohydrates decreased with increasing level of N, more with NH4+‐N than NO3−‐N. The causes of nitrate‐N accumulation in grass are discussed.
Insecticidal activity of fresh and dry pyrethrum flowers
Authors: Godin P. J. , Inglis Helene S. , Stevenson J. H. 
Published: November 2006

AbstractAcetone extracts of fresh pyrethrum flowers and of flowers dried at a low temperature over silica gel were compared by gas‐liquid chromatography and by biological assay. Results showed that there was no effect of drying on the amounts of the known insecticidal constituents and that activity was not diminished. Tests on extracts of pyrethrum flowers dried at various temperatures showed no significant change in composition or activity when flowers were dried at temperatures below 80°, but at 120° there was a significant loss.
Carbonyl compounds and the non‐enzymic browning of lemon juice
Authors: Clegg K. Mary , Morton A. D. 
Published: November 2006

AbstractDuring the non‐enzymic browning of lemon juice the build‐up of carbonyl compounds is believed to be associated with the breakdown of ascorbic acid. This has been studied by separation of their 2,4‐dinitrophenylhydrazine derivatives on thin‐layer chromatograms, and by spectroscopic examinations. The results have been compared with those from model systems. Twelve carbonyls were found in browned samples, half of these have been tentatively identified and the remainder have been classified as aldehydes or ketones. Work with model systems confirmed that the α,β‐unsaturated carbonyls are potent browning agents and also that dicarbonyls of the glyoxal type make a contribution to browning in the early stages. The rǒle of sugars in these systems has been considered.
Effects of protein intake on the storage of copper in the liver of sheep
Authors: Macpherson A. , Hemingway R. G. 
Published: November 2006

AbstractDeath from copper poisoning resulting from administration of 1·0 g. of CuSO4,5H2O per day occurred after periods ranging from 10 to 34 weeks in two groups of housed sheep on concentrate diets containing 10 and 20% of protein, respectively. The additional protein was dried blood meal. Those on the higher protein intake appeared to be the more resistant, although the concentration of copper in the liver of both groups were in the dangerously high range. Rather less than 3% of the supplementary copper was stored in the liver. Additional protein did not affect copper storage when sheep on basal diets providing 10% of protein and containing about 6 p.p.m. of Cu were supplemented with 10 mg. of Cu per day.
The refractive index of the muscle of fish and shellfish. I.—A possible method for measuring protein deterioration in fresh and frozen cod
Authors: Elerian M. K. 
Published: November 2006

AbstractThe refractive index of cod muscle was measured during stowage of the whole fish in ice and during cold‐storage of fillets at −14° and −29°. These treatments caused, respectively, a decrease and an increase in refractive index, the increase at −14° being faster than that at −29°. The possibility of using refractive index to measure the deterioration of fish is discussed.
The nitrogenous constituents of the dehydrated mushroom, Boletus edulis, and their relation to flavour
Authors: Craske J. D. , Reuter F. H. 
Published: November 2006

AbstractSteam distillation of dehydrated Boletus edulis gave a ‘flavour essence’ which contained only the off‐flavour components of the sample and was reminiscent of town gas and/or rubber. The true mushroom flavour was found to be non‐volatile, the residue after distillation being of undiminished flavour intensity.About half of the sample was water soluble and this extract contained all of the flavour components. These were concentrated into the basic fraction by an ion‐exchange technique, and further separated into fractions containing amino‐acids of progressively increasing basicity by a displacement development ion‐exchange chromatographic technique. The most basic compounds tasted most characteristically of mushrooms, but it was clear that all the nitrogenous constituents contributed something to the overall flavour profile. The contribution of the highly basic amino‐acids is considered to be especially important as it was found that their flavours lingered in the mouth and were therefore savoured more strongly than would be expected simply from a consideration of their taste intensity as measured by threshold dilution technique.
The organic acids in tea plants. A study of the non‐volatile organic acids separated on silica gel
Authors: Sanderson G. W. , Selvendran R. R. 
Published: November 2006

Abstract
Succinic, oxalic, malic, citric, isocitric, and five unknown acids have been found at appreciable levels (>0·1 μequiv./g. fresh wt.) in tea shoot tips. The major acids quantitatively were oxalic, malic and citric acids. The acids studied were recovered quantitatively from plant extracts, but they accounted for less than one‐fourth the total acidity present in tea shoot tips.
The acid levels in shoot tips varied quantitatively between clones and between sampling dates, and also both quantitatively and qualitatively between different parts of the tea plant.
Changes in the levels of organic acids take place in tea shoot tips during the manufacture of tea which are typical of senescing plant tissues. Notably, the levels of succinic and malic acids are markedly reduced during withering. The level of oxalic acid, however, remains nearly constant throughout manufacture.
Studies with 14CO2 on intact plants showed that all of the organic acids studied are metabolically active except oxalic acid.
Effects of fat content on diffusion of water in fish muscle
Authors: Jason A. C. 
Published: November 2006

AbstractThe coefficients of diffusion of water, Di and Dii, associated with states of ‘high’ and ‘low’ hydration respectively in fish muscle are sensitively dependent on the amount of fat present. The diffusion resistivity D−1 for various species may be represented in both cases by straight lines of the form

Where F is fat content and α and β are constants. Although the results for various species appear to fall about common lines for Di−1 and Dii−1, the diffusion of water in the muscle of dogfish (Squalus acanthias L.) is anomalous in certan respects.The experimental evidence is generally incompatible with a muscle microstructure consisting of a dispersion of fat in a non‐fatty medium, as is commonly supposed, but is more in accord with one consisting of relatively non‐fatty tissue entirely surrounded by fat, the thickness of which increases linearly with fat content.
Synthesis and insecticidal activity of N‐methylenefluoroacetamide derivatives
Authors: Pianka M. , Polton D. J. 
Published: November 2006

AbstractSeveral N‐methylenefluoroacetamides were synthesised and tested for contact (2 days) and systemic (7 days) activity against A phis fabae. The contact activity seemed to depend on the ease of hydrolysis to fluoroacetamide. Generally, the systemic activity of the compounds was similar to that of fluoroacetamide, indicating that, during the longer period allowed for the systemic tests, hydrolysis to fluoroacetamide took place as the first step. Some compounds were too stable and showed little contact or systemic activity. The acaricidal activity and mammalian toxicity were also determined. A hydrolysis path is indicated, and the greater stability of certain derivatives is discussed.
The yields of leaf protein extracted by large‐scale processing of various crops
Authors: Byers M. , Sturrock J. W. 
Published: November 2006

AbstractThe yields of leaf protein that can be expected from the large scale extraction of several crops grown at Rothamsted were determined by measuring the fresh weight of leaves, the dry matter and nitrogen content of the leaf and the percentage of protein‐N extracted.The yields, expressed as kg. of extracted protein per hectare, were greater for cereals than for legumes and other species. The yield depends on species, variety, season, age of the plant and on the ability to regrow after cutting. The response of both wheat and barley to additional fertiliser N was variable. More protein is extractable from young leaves, but in general the percentage of N extracted bears little relation to the N content (as % of dry matter) of the leaf.The results suggest that by using a suitable succession of crops it should be possible to get 1000 kg. of protein from a hectare in a year.
Studies on the nutritional value of foods treated with γ‐radiation. II.—effects on the protein in some animal feeds, egg and wheat
Authors: Kennedy T. S. 
Published: November 2006

AbstractThe effect of γ‐radiation on the protein nutritive value of certain animal feeds (protein concentrates), frozen whole egg, whole wheat and wheat gluten was measured by use of a microbiological method. There was little change in nutritive value of the animal feeds with doses of 0·5 and 1·0 Mrad and no change with frozen egg at.0·5 and 5·0 Mrad. Whole wheat showed no loss at 0·2 Mrad; a 6% loss at 1·0 Mrad was not increased further at 5·0 Mrad. Gluten prepared from wheat and then irradiated was unchanged at 0·02 Mrad but losses of 5, 7 and 26% were shown with doses of 0·2, 1·0 and 5·0 Mrad respectively.Following amino‐acid supplementation studies and microbiological assays for methionine, loss of availability of this amino‐acid was demonstrated to be principally responsible for the lowering of the nutritive value of the 5·0‐Mrad‐irradiated wheat gluten.
Bromine residues in oil seeds and oil meals after fumigation with ethylene dibromide
Authors: Alumot Eugenia , Calderon M. 
Published: November 2006

AbstractFumigation of oil seeds (sunflower, soya‐bean, groundnuts and cotton) with ethylene dibromide (EDB) was performed at two concentrations in order to establish the effect of seed structure and oil content on the sorption and reaction of EDB. Amounts of the fumigant sorbed were markedly increased by the presence of fat in the seeds. Hulls generally inhibited sorption. Amounts of bound bromine were not affected by the presence of fat and were proportional to the initial concentration of EDB in the seeds. No bound bromine was found in the oil fraction of the seeds. About one month's airing was needed to free the seeds of sorbed EDB.
Studies on the quality of some improved varieties of indian wheats
Authors: Bains G. S. , Irvine G. N. 
Published: November 2006

AbstractA number of techniques, including milling and baking, were employed to assess the quality of seven improved varieties—NP‐710, −718, −797, −799, −823 and −824, and C591—of Indian wheats which have shown several distinctive features. The yields of straight‐grade flour were high in all cases, ranging from 74·2% (NP‐799) to 77·1% (NP‐824). The maximum extensograph curve area (155 cm.2) and 100‐g. flour loaf volume were given by the variety NP‐824. The doughs are tight and short as indicated by the poor extensibilities and steep heights of the extensograms. The varieties showed practically no response to the improver potassium bromate. The variety NP‐823 rated as good as NP‐824 in a number of tests, but its loaf volume was significantly lower than that of NP‐824. The only abnormal feature of the flour of this variety was its paste viscosity which was the lowest in the whole series. The protein content of C591 varied considerably when grown in different locations, but it maintained its milling and baking qualities, the loaf volume per unit protein being the second highest among the varieties tested.
The evaluation of some red marine algae as a source of carrageenan and of its κ‐ and λ‐components
Authors: Black W. A. P. , Blakemore W. R. , Colquhoun J. A. , Dewar E. T. 
Published: November 2006

AbstractThe red seaweeds, Chondrus crispus, Gigartina stellata, G. radula, G. acicularis, G. pistillata, Eucheuma spinosum, and Polyides rotundus, have been evaluated as a source of carrageenan and of its k‐ and λ‐components. The fractionation of carrageenan from C. crispus with potassium ions does not always give a sharp separation into ‘pure’ k‐ and λ‐components and is dependent on habitat. Seasonal variations in total yield, k/λ ratio, optical rotation and chemical composition were observed.G. stellata and G. radula give poor separations but G. acicularis and G. pistillata give sharp fractionations and the proportion of λ‐polysaccharide in these two species is much higher than that in C. crispus. Approximately 30% of the dry weight of these seaweeds is λ‐carrageenan.Carrageenan from E. spinosum cannot be fractionated with potassium ions. This polysaccharide, which accounts for ˜55% of the dry weight of the seaweed, is structurally related to k‐carrageenan but has a higher sulphate ester content. The extract of P. rotundus is also insensitive to potassium ions but differs from that of E. spinosum in having a negligible content of 3,6‐anhydrogalactose.Different carrageenans have been depolymerised to give products of low viscosity and high sulphate content. This was achieved in the case of k‐carrageenan and carrageenan from E. spinosum by mild treatment with acid. Two methods are described for λ‐carrageenan; the first involves oxidation with periodate, reduction with borohydride, and mild acid hydrolysis. The second method, which is cheaper and more effective, employs hypochlorite as oxidant. A series of degraded products is listed.
Determination of ethylene dibromide in fumigated feeds and foods by gas–liquid chromatography
Authors: Bielorai Rachel , Alumot Eugenia 
Published: November 2006

AbstractA method is described for determination of ethylene dibromide in fumigated material by gas–liquid chromatography. The steam distillation method of Kennett & Huelin7 was used for extraction of the ethylene dibromide from the samples analysed. A good correlation was obtained by comparison of the gas–liquid chromatography with the chemical methods.
Changes occurring in the cell walls of strawberries during ripening
Authors: Neal G. E. 
Published: November 2006

AbstractThe changes occurring during maturation in the structure of the cell walls of two varieties of strawberries have been studied. Ripening is accompanied by a splitting of the middle lamellae of cell walls of large cortical parenchyma cells. A relationship has been found between the degree of methylation of the pectinous middle lamella and the ability of divalent cations to ‘firm’ the tissue. Chemical analyses of the polysaccharide content of the cell walls have indicated that ripening is accompanied by a change in the cationic stabilisation of the pectinous materials. The theory is advanced that the separation of the parenchyma cells during ripening is associated with changes in cationic content of the pectinous middle lamella, which in turn is related to changes in degree of methylation of that material. It is suggested that this process is similar to that known to occur in the ‘sliding‐growth’ process of certain plant cells.
The crystallisation of lactose with particular reference to its occurrence in milk powder
Authors: Bushill J. H. , Wright W. B. , Fuller C. H. F. , Bell A. V. 
Published: November 2006

AbstractX‐ray diffraction patterns and infra‐red spectra have shown that although the lactose in spray‐dried milk powder is normally in the amorphous state, it can sometimes be present as the crystalline α‐monohydrate, or in an unusual crystalline form.Studies have been made of the absorption and subsequent loss of moisture in humid atmospheres by (a) spray‐ and freeze‐dried milks, and (b) spray‐ and freeze‐dried lactose prepared from lactose solutions. It is shown that milk powders exposed to these conditions generally contain α‐lactose monohydrate, but the spray and freeze‐dried lactose produce a mixture of the α‐monohydrate and the β‐anhydride.For identification purposes all the known crystalline forms of lactose have been prepared and studied by X‐ray diffraction and infra‐red methods, and it has been found that the above‐mentioned unusual crystalline form of lactose found in some milk powders is the anhydrous molecular compound consisting of α‐lactose and β‐lactose in a molar ratio of 5 : 3. This compound gives an X‐ray diffraction pattern which is different from, but an infra‐red spectrum similar to, those of the stable α‐lactose anhydride.
The determination of nitrogen in woody tissue
Authors: Rennie P. J. 
Published: November 2006

AbstractA simple routine semi‐micro Kjeldahl procedure is described suitable for woody tissues. Some 250 mg. of milled tissue is digested with potassium sulphate, conc, sulphuric acid and mercuric oxide under a thermostatically controlled three‐stage electrical heating schedule, digestion being continued for 2 h. after clearing.Tests conducted with a variety of woody tissues give good reproducibility—coefficients of variation being all <3·5%, and N‐content values higher than by three other procedures based on combinations of selenium, copper sulphate and vanadium pentoxide. Recoveries from a range of N‐reference standards typical of compounds or structures present in plant materials show, with two exceptions, a high accuracy—within ·0·6%, and a high precision—coefficients of variation <0·6%.The poor recovery (85·3%) obtained with canavanine, which contains a N–O bond, is discussed and care is necessary before analysing tissues from families, e.g., the Leguminosae, liable to contain such linkages.
Physical aspects of the drying of groundnuts
Authors: Myklestad O. 
Published: November 2006

AbstractInvestigations have been carried out to establish an economic method for drying unshelled groundnuts to a safe storage moisture content of 9–12% on dry weight in a typically subtropical environment (Queensland). Sorption isotherms on groundnuts showed that to dry the nuts satisfactorily without heat, the ambient air should have R.H. below 75%; but as this condition occurs in the area on the average for only 63% of the time during the harvest season, techniques involving preliminary drying by natural curing in windrows followed by hot‐air drying were studied. In a pilot‐scale dryer of 40 cu. ft. capacity, an air flow of about 21 cu. ft./(min.) (cu. ft. load) at an air temperature of 100°F satisfactorily reduced the moisture content from 31% to 12% (dry basis) in 24 h. A larger industrial bin dryer of 750 cu. ft. capacity gave even more satisfactory results. Fuel consumption for the larger unit was 2·2 gal./h. at a fuel cost of 24d. (Australian)/gal., and a load of about 7 tons (wet) could therefore be dried at a fuel cost of about 0·12d. (Aust.)/lb. product. The results might be applicable to the drying of groundnuts in other subtropical areas, and the fundamental principles involved might prove applicable to the drying of farm crops in general.
A simple method for determining small amounts of formaldehyde in silage
Authors: Neumark H. 
Published: November 2006

AbstractA method is described by which formaldehyde, present in silage, is precipitated by 2,4‐dinitrophenylhydrazine and the formaldehyde, liberated from the hydrazone by hot concentrated sulphuric acid, is assayed photometrically with chromotropic acid reagent.