bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties of proteins
Authors: Neuberger A.
Published: November 2006

The history of protein chemistry over the last 60 years is briefly reviewed. The structural and analytical chemistry of proteins was well advanced by 1914; the inter‐war period was distinguished by the emphasis placed on the use of physico‐chemical methods. Recent work on the reversible dissociation, denaturation and free amino groups of proteins is reviewed in some detail. It is pointed out that labile bonds, not of the usual covalent type, must be responsible for maintaining the native configuration of proteins. The possible nature of such bonds is discussed and it is suggested that electrostatic linkages between the guanidino groups of arginyl residues and carboxyl groups may be important in this respect.
A method for the determination of the relative availability of nitrogen in nitrogenous fertilizers
Authors: Hamence J. Hubert
Published: November 2006

The process depends upon the determination of the nitrate nitrogen produced from the fertilizer when it is mixed with soil under such conditions as to give the maximum rate of nitrification; the most important conditions in the test are the moisture content of the soil and the presence of calcium carbonate. The nitrate nitrogen produced from the fertilizer in 18 days is compared with that produced from dried blood containing an equivalent amount of nitrogen and treated under identical conditions, and the availability of the fertilizer is calculated by taking that of dried blood as 100.

Results of the availability of the nitrogen in some of the commoner organic nitrogenous fertilizers are given; they show that the suggested test gives a better measure of the availability of leather residues than is given by the Street permanganate test at present used for this purpose.
The purification of high‐density beet juices from dried beets
Authors: Mitchell Thomas J.
Published: November 2006

The dehydration of sugar beets offers an extension of the normal factory campaign from 100 days to 250–300 days. Except in specially favourable locations, economies in process charges have not so far offset the cost of drying.

Diffusion‐juices of high density are easily obtainable, but offer considerable difficulty in the process of purification; at densities above 20° Brix, the normal carbonatation method of purification is not easy to apply owing to the high viscosity and low purity of these juices and the presence of reducing sugars; the removal of impurities from dried beet diffusion‐juices has been investigated by analysis of the juices before and after treatment with lime, aluminium sulphate, and a final acid reagent (SO2 or CO2); juices of up to 40° Brix have been successfully treated.
The influence of environment upon the composition of sunflower seed oils. I.—Individual varieties of sunflowers grown in different parts of Africa
Authors: Barker C. , Hilditch T. P.
Published: November 2006

Sunflowers grown from named varieties of seed in Southern Rhodesia, Kenya and Tanganyika give seed oils of somewhat varying composition, but the seed oils from all varieties grown in any one location are practically identical in composition. Similarly, sunflower seed oils grown in three different parts of Zanzibar from two sorts of seeds (black and cream) are widely different in composition; here the oils from black seeds were somewhat more unsaturated than those from the cream seeds, but the main difference again is connected with the place of growth and, more specifically, seems to be connected with the rate of development of the seed. Seed harvested only two months after planting gave oils of extremely low unsaturation which, indeed, were not dissimilar from groundnut oils in linoleic acid content. The component glycerides of the least unsaturated oil (iodine value 94.7) have been determined.
The electrometric estimation of chloride in meat. III.—The influence of heating in the presence of nitric acid on the combination of silver with meat protein
Authors: Ingram M. , Bryan J. M.
Published: November 2006

In the electrometric method for the estimation of chloride in meat products, errors due to absorption of silver by protein are eliminated by pre‐heating an extract of the product with 0.5N‐nitric acid on a boiling water‐bath for at least 15 minutes before titration.
Structure and synthesis in the group of deoxy‐sugars
Authors: Overend W. G. , Stacey M.
Published: November 2006

Several methods of synthesis of 2‐deoxyribose are outlined and crystalline derivatives of the sugar suitable for its characterization are described. The reactions of this sugar have been studied and methylglycopyranosides and the αβ‐furanoside of it have been prepared. The constitutions of these glycosides have been established by various methods. That the reactions of 2‐deoxyribose are general for other 2‐deoxy‐sugars was demonstrated by carrying out similar conversions with 2‐deoxyglucose and 2‐deoxygalactose. It has been shown that the methylene (deoxy) group at position C2 of the sugar greatly increases the lability of substituents on the glycosidic carbon atom. Preliminary investigations with suitable derivatives of 2 : 3‐dideoxyglucose indicate that the introduction of another deoxy group adjacent to that at C2 in the sugar enhances this effect.
Search for insecticides: Chemical constitution and insecticidal activity
Authors: Bhargava P. M. , Sen A. B.
Published: November 2006

The synthesis of a number of compounds containing mostly a chlorobenzene nucleus as the toxic grouping and a CCl2 (as CHOH·CC13, COCC13, O·COCC13 or > CHCC13) or a COCH3 group as the chief lipoid‐soluble component, has been described by the authors in the earlier papers of this series.2, 3, 4, 5 This paper incorporates the results of the investigation of the insecticidal action of 35 of those compounds (containing a combination of a lipoid soluble and a toxic grouping), on the rice‐moth Corcyra cephalonica (belonging to the family Pyralidae, order Lepidoptera) which is very common in India, employing the technique of direct spraying. The results have been reviewed in the light of the theory of Läuger, Martin and Müller,1 correlating insecticidal action and chemical constitution. A few generalizations pertaining to the effect of some individual groups on the toxicity of a molecule have been put forward. It is concluded that, apart from the presence of a toxic and a lipoid‐soluble grouping, certain other factors of yet unknown nature also play an important role in conferring high insecticidal activity.
The routine determination of exchangeable bases in soils by the lundegardh flame spectrographic method
Authors: Black I. A. , Smith E.
Published: November 2006

Considerable changes have been made in Mitchell's methods for spectrographic determination of exchangeable bases in soils. The following paper describes these modifications which include (a) the use of an automatic leaching apparatus for extracting the soils with ammonium acetate: this economizes in material and time and permits an approximate estimation of exchangeable hydrogen to be made; (b) the use of aqua regia for destroying organic matter; (c) a combination of new dilutions and new standards with the use of a metol developer for the plate: this considerably extends the range of soils dealt with by the standard routine; (d) a modification of the plate holder, enabling 88 spectrograms to be recorded on one 5‐in. × 4‐in. plate; and (e) a method of plotting working curves from the photometric data which is considered to have several advantages over those in general use.
The mechanism of pectin jelly formation with respect to pH conditions, with particular reference to setting temperature phenomena
Authors: Harvey H. G.
Published: November 2006

The phenomenon of setting temperature of pectin‐sugar jellies is considered in the light of the dissociation hypothesis of jellying propounded earlier by Hinton. The concept of setting temperature is shown to follow directly from, the hypothesis and the dependence of setting temperature on such factors as PH value, pectin concentration and soluble solids is accounted for.

A slight modification of the original theory provides a quantitative explanation of some of the differences in jellying behaviour caused by different metallic buffer salts. The modified theory is shown to lead to a simpler conception of effective ionization and this in turn is used to account for some of the difference in jellying behaviour brought about by alterations in the degree of esterification of the acid groups of the pectin molecule.
The composition of leopard seal blubber fat
Authors: Winter G. , Nunn W. J.
Published: November 2006

The results of a detailed analysis of the fatty acid composition of the blubber fat from a leopard seal are reported.
The possible use of fish guts as food for animals
Authors: Lovern J. A. , Godden W.
Published: November 2006

The most promising of the various forms of ‘refuse’ still discarded to waste in British fisheries is the guts—mainly stomachs and intestines—which are thrown overboard from the trawlers. Such material is capable of giving a yield and type of meal comparable to that obtained from the usual fish offal. The guts must be preserved in order to bring them back to port, and formaldehyde at 0.4% by weight of the guts is a satisfactory preservative. Sodium nitrite seems less effective. Seaweed meal may be used but the amount required is excessive (50–100%) and the final product is not very palatable. Meal made from guts preserved with formaldehyde is palatable to animals and shows no evidence of toxicity. The protein is readily hydrolysed by pepsin in vitro, and by digestive enzymes of the pig in vivo. Much of the total nitrogen of the meal cannot be accounted for as ‘true protein,’ and is probably present as partly hydrolysed protein fragments. Nevertheless, it is in a form available to the pig, as shown by nitrogen‐balance studies.
Occurrence of an amylopectin in the fruit of the granadilla (Passiflora edulis)
Authors: Cillie G. G. , Joubert F. J.
Published: November 2006

The starch present in the fruit pulp of the granadilla (Passiflora edulis) has been isolated and examined. Its properties are in accord with its formulation as an amylopectin in which the side chains have an average length of 17 glucose residues.
An indirect colorimetric determination of calcium in plant material
Authors: Cornfield A. H. , Pollard A. G.
Published: November 2006

Calcium is separated as oxalate in a centrifuge tube. The precipitate is estimated by dissolving in a known excess of ceric sulphate, excess of which is then determined absorptiometrically. The range covered is 100–1000 μg. calcium.
Transport trials and laboratory tests on food containers. I.—Lined kraft‐paper bags
Authors: Allen R. J. L. , Paine F. A.
Published: November 2006

The serviceability of lined kraft‐paper bags for packaging cornflour has been assessed in statistically‐designed transport trials. Closely similar results were obtained by laboratory drop‐tests. Conventional strength‐tests on the kraft paper showed no correlation with the behaviour of the bags in service.
A new mercurial with apparent systemic properties as a seed dressing
Authors: Hopf P. P. , Lhoste J. , Ravault L.
Published: November 2006

Phenyl mercuric dinaphthylmethanedisulphonate has been investigated as a seed dressing. Considerations leading to the choice of this material are discussed and the substance is compared with other materials used in seed disinfection. It is shown that this material is an effective fungicide and of comparatively low toxicity to animals and germination.
Studies on commercial octamethylpyrophosphoramide (Schradan). II.—Determination of toxic residues
Authors: David A. , Hartley G. S. , Heath D. F. , Pound D. W.
Published: November 2006

A method of determining small traces of the insecticide in treated crops is described and the validity of the method for assessment of toxic risk to the consumer is discussed. The method is sensitive to 0·1 mg. insecticide per kg. of plant tissue in the absence of interfering substances which may, however, give rise to ‘blanks’ of up to 1 mg./kg.
The volumetric semi‐micro determination of magnesium in plant and soil extracts
Authors: Cornfield A. H. , Pollard A. G.
Published: November 2006

After removal of calcium as oxalate, magnesium (50–500 μg.) is precipitated as magnesium ammonium phosphate in a centrifuge tube in the presence of citrate, which prevents the interference of iron and aluminium. The magnesium in the precipitate is determined by titration with standard hydrochloric acid using the ‘4.5’ indicator. Manganese if present interferes but may be allowed for by determining the manganese in the precipitate and applying a correction factor.
Studies on linseed oil. II.—Partial separation of the unsaturated acids of linseed oil by counter‐current distribution between pairs of immiscible solvents
Authors: Davies L. S. , Edwards W. G. H.
Published: November 2006

The separation of linseed oil fatty acids by counter‐current distribution between pairs of solvents has been investigated and a linolenic acid concentrate, containing linoleic acid only as impurity, has been obtained.
Photo‐decomposition of rotenone in spray deposits. III.—Kinetics of the photo‐decomposition
Authors: Rao N. V. Subba , Pollard A. G.
Published: November 2006

Special artificial light sources have been designed and constructed to investigate the photo‐decomposition of rotenone in controlled conditions. The various factors that affect the decomposition are investigated, and the rates of decomposition of rotenone and derris deposits on exposure to sunlight and the artificial light sources are determined. The rates of decomposition indicate the reaction to be of the first order. From the data obtained, the period over which the deposits are likely to remain active under field conditions is estimated.
The influence of environment upon the composition of sunflower seed oils. III.—Oils from sunflower seeds grown in different regions of Australia
Authors: Bridge R. E. , Crossley A. , Hilditch T. P.
Published: November 2006

Seeds grown in field trials of several varieties of sunflowers in diverse regions of the Australian Commonwealth have been examined in regard to the composition of their fatty oils. The results have shown close parallelism with similar studies (Barker & Hilditch, 1950a) of African sunflower seeds in that there is great variation in the proportions of linoleic and oleic acids in the oils from different localities. Seed grown in the Northern Territory gave oils of quite low linoleic content (31–36%) which would be exceptionally suitable in the edible fat industries. Those from the most southerly latitudes, on the other hand, contained 65% or more of linoleic acid and would be of interest to the paint trade. Seeds from intermediate latitudes, such as New South Wales and Queensland, contained oils of the more usual type with 50–60% of linoleic acid in their component acids.
Variations in the composition of some linolenic‐rich seed oils
Authors: Hilditch T. P.
Published: November 2006

The receipt at different times during the past seven years of a large number of specimens of candlenuts, rubber seeds, linseed and hemp seeds has resulted in an accumulation of data which serve to illustrate the possible range of variation in the composition of each of these seed oils. Candlenut oils seem prone to exhibit variations, usually of a minor but occasionally of a major order, in their content of linolenic acid; and it is shown that definite but minor variations occur in the oils from different fruits of the same tree. Rubber seed oils, so far as at present studied, have shown relatively little difference in composition. Linseed oils from seed grown in England or in South Africa have proved satisfactory as regards a high content of linolenic acid. The few specimens of hemp seed oil studied in detail show considerable similarity in composition.
Evaporation in low vacuum from warm granular material (wheat) during the falling‐rate period
Authors: Jones C. R.
Published: November 2006

The effect of various factors on rate of drying of wheat (below the critical moisture content) has been studied at temperatures in the range 12°‐45° c., and under absolute pressures in the range 0.5–8 cm. of mercury. The results imply that the rate of diffusion of moisture within individual grains remains the factor governing rate of drying in vacuo in the manner known for air‐drying in the falling‐rate period, and that the rate of change of the diffusion coefficient with temperature (over the range 12° 46° c.) is the same as that of the vapour pressure of water. Within the range 13–30% moisture content (dry‐weight basis), the rate of drying in vacuo is directly proportional to the free water content, but the term ‘free’ means the difference, not between total and equilibrium moisture contents as in air‐drying, but between total and firmly held or bound water, the level of which must depend upon temperature: at 30°‐40° c. it is about 9–10% (dry‐weight basis). However, with wheats of similar total moisture content, the rate of drying is greater if the concentration of moisture in the outer layers is higher than that in the interior of individual grains, as in freshly wetted wheat. Variation in pressure affects directly only the rate of removal of vapour which has already left the solid, but this in turn affects the rate of drying. The effect depends on impedance to vapour movement caused by form of apparatus and disposition of the material, and can be substantially counteracted by admission of a small sweeping current of air, the optimum proportion of which is equimolecular with respect to the evaporated water.
Analytical studies on the carbohydrates of grasses and clovers. I.—Development of methods for the estimation of the free sugar and fructosan contents
Authors: Laidlaw R. A. , Reid S. G.
Published: November 2006

Techniques have been evolved for the estimation of the free sugars present in grasses and clovers and for the estimation of fructosan in grasses. By the use of the paperchromatographic procedure each may be determined individually at any stage of growth.
The influence of soya flour on bread doughs. II—The inhibition of the proteolytic enzymes of malt and wheat flours
Authors: Learmonth E. Mitchell
Published: November 2006

Aqueous extracts of soya beans are shown to inhibit the proteolytic enzymes of malt on a gelatin substrate and those of wheat flour, and papain, on a gluten substrate. The effect of the inhibitor is compared with that of potassium bromate.
Studies on commercial octamethyl‐pyrophosphoramide. III—decomposition of the insecticide in plants, using 32P as a tracer
Authors: Heath D. F. , Lane D. W. J. , Llewellyn Margaret
Published: November 2006

Test‐plots of strawberries, sugar beet, hops and brussels sprouts were sprayed with the mixed insecticide, made radioactive by synthesizing it from 32P, at various times from May to October. The insecticide sprayed contained roughly equal proportions of octamethylpyrophosphoramide, (Me2N)4P2O3, and its higher homologue, (Me2N)5P3O5.

On analysing the sprayed crops at various times after spraying it was found that the concentration of both constituents in the plant fell at much the same rate, and that this rate varied little amongst the plant species treated providing all were treated at the same time of year. The rate slowed somewhat, however, as the year progressed from May to September, and became very slow indeed in October.

It was also shown that the plants decomposed the insecticide. It is likely that practically the whole lowering of concentration with time is attributable to this decomposition.
Studies on commercial octamethyl‐pyrophosphoramide. IV—The decomposition of pyrophosphoric acid tetra(dimethylamide) and orthophosphoric acid tri(dimethylamide) in the living plant
Authors: Heath D. F. , Lane D. W. J. , Llewellyn Margaret
Published: November 2006

Sugar beet and strawberry plants were treated with octamethylpyrophosphoramide, R4P2O3, and tri(dimethylamino)phosphine oxide, R3PO [R = Me2N‐], containing 32P. Both are decomposed at similar rates in both sugar beet and strawberries. When sugar beet treated with R4P2O3 were analysed 10–14 days after treatment, it was shown that the 32P in the beet existed only as unchanged R4P2O3 and products not extractable from water by chloroform. When R3PO‐treated‐beet were analysed it was found that, besides unchanged R3PO and non‐chloroform‐extractable compounds, some of a compound less extractable than R3PO by chloroform was produced. The way these results bear on the mechanism of decomposition of R3PO and R4P2O3 in the plant is discussed.
Survey of soils for spores of Clostridium botulinum (union of South Africa and South West Africa)
Authors: Knock G. G.
Published: November 2006

The absence of any authenticated case of human botulism in South Africa suggested that Clostridium botulinum Types A, B or E might be rare organisms in the soils of this country.

Three out of 102 samples of soil from the Union of South Africa and South West Africa produced Clostridium botulinum Type‐B toxin when cultured. Clostridium botulinum Type B was obtained in pure culture from the three toxic cultures by a method described.

The isolation in South Africa of Clostridium botulinum Type B is reported for the first time : a description of the strains is given.

The factors which militate against toxin production by Clostridium botulinum in cultures of soil are discussed, and the probable operation of these same factors in reducing the chances of toxin formation in foods is suggested.
The significance of peroxide determination in fats by the dichlorophenol‐indophenol method
Authors: Hartman L. , White Margaret D. L.
Published: November 2006

PEROXIDES IN FATS

The dichlorophenol‐indophenol method recommended by Hartmann & Glavind (1949) for determination of peroxides in fats has been investigated and found to be subject to interference by atmospheric oxygen. In the presence of air higher results are obtained with this method than with the iodometric procedure but on exclusion of oxygen they are reduced below the iodometric values, which presents an analogy with the ferric thiocyanate method of Lips, Chapman & McFarlane (1943). Since the analysis of hydrogen peroxide and benzoyl peroxide with the dichlorophenol‐indophenol method yields in the presence of air results which are too high, peroxide values obtained with this method for fats may be regarded as being incorrect.
Extraction of potassium from soil by electrodialysis and by ammonium acetate leaching. II—Examination of potassium‐hydrogen clays
Authors: Agarwal B. R. , Pollard A. G.
Published: November 2006

Electrodialysis of potassium‐hydrogen clays for one hour in a Marsden cell removed substantially the same amount of potassium from the clays as did leaching with normal ammonium acetate solution (as used for determining exchangeable bases). It is suggested that potassium removed from soil by more prolonged dialysis is derived from non‐exchangeable or fixed forms.
Effects on soils and crops of varying depths of cultivation. I.—some preliminary observations
Authors: Constable D. H. , Pollard A. G.
Published: November 2006

The effects on the moisture content, and on the concentration of the major nutrients Ca, Mg, N, P, and K in the soil solution of ploughing to different depths, and certain effects on the crops have been studied. A few significant differences are shown, but there has been no consistent trend, nor does any particular plough depth appear superior to the others as a whole.
The chrysanthemumcarboxylic acids. V.—hydration of the chrysanthemic acids
Authors: Harper S. H. , Thompson R. A.
Published: November 2006

In boiling dilute sulphuric acid hydration of (±)‐trans‐chrysanthemic acid occurs to give the crystalline (±)‐trans‐δ‐hydroxydihydrochrysanthemic acid. In like manner (+)‐and (‐)‐trans‐chrysanthemic acids yield the crystalline (‐)‐ and (+)‐trans‐δ‐hydroxy‐dihydrochrysanthemic acids respectively. No racemization occurs as the recovered ( + )‐and ( ‐ )‐trans‐chrysanthemic acids have unchanged specific rotation.

The lactonization of (±)‐cis‐chrysanthemic acid to (±)‐cis‐dihydrochrysanthemo‐δ‐lactone in boiling dilute sulphuric acid is shown to be reversible and to constitute an example of lacto‐enoic tautomerism. ( + )‐ and ( ‐ )‐cis‐Chrysanthemic acids are similarly lactonized to the crystalline (+)‐ and (‐)‐cis‐dihydrochrysanthemo‐δ‐lactones. The latter lactone is not identical with (‐)‐pyrocin, whose structure is confirmed as (‐)‐β‐isobutenyliso‐hexano‐γ‐lactone.
Measuring the physical characteristics of flour : A method of using the chopin alveograph to detect the effect of flour improvers
Authors: Bennett Ruth , Coppock J. B. M.
Published: November 2006

A new technique is described by which, it becomes possible to use the Chopin Alveograph for detecting the effect of improvers in flour. In the standard technique, dough pieces for test are shaped by extrusion and flattening by rolling and are tested 20 minutes after mixing.

The modified technique involves keeping the dough in bulk for three hours at constant temperature, after which test pieces are then weighed off, moulded and again tested. It has been found that the change so recorded satisfactorily reveals the effect of flour treatment; a resting time in the dough and moulding of the dough are required to accomplish this adequately.

Examples are given of the use of the method on flours treated respectively with potassium bromate, nitrogen trichloride, chlorine dioxide and ascorbic acid.
The mineralization of the nitrogen of soils during incubation: Influence of pH, total nitrogen, and organic carbon contents
Authors: Cornfield A. H.
Published: November 2006

The ammonia, nitrite and nitrate which accumulated in 19 soils (containing less than 0.25% of total nitrogen and which had not recently received inorganic nitrogen fertilizers) during three weeks' incubation, both in the presence and absence of added chalk, at 28° and optimum moisture content, were determined. Ammonia accumulation was generally high in acid and low in neutral and alkaline soils. The addition of chalk resulted in less ammonia accumulation in all but one of the soils. Small amounts of nitrite accumulated in six of the soils; this occurred only when some acid soils were incubated with added chalk. All the soils made a positive response in nitrate and total mineral nitrogen accumulation to chalk additions, the response decreasing as the original soil pH increased. In the absence of added chalk total mineral nitrogen accumulation was significantly correlated with total nitrogen but not with organic carbon, whereas in the presence of added chalk it was poorly correlated with both factors. Partial correlations showed a similar trend. In the absence of added chalk, nitrate accumulation was significantly correlated with total nitrogen and organic carbon, and in its presence with total nitrogen only. The only partial correlation that was significant was that between organic carbon and nitrate accumulation in the absence of added chalk. The carbon/nitrogen ratio was not correlated with nitrate or total mineral nitrogen accumulation per unit of total nitrogen present. A comparison of the amounts of nitrogen mineralized during three and six weeks' incubation indicated that air‐drying of soils causes a certain amount of partial sterilization. If the incubation method is to be used as a measure of the availability of the organic nitrogen in soils, more satisfactory results should be obtained by incubating the original soil and determining total mineral nitrogen accumulation than by incubating with added chalk and determining nitrate only.
Changes in nitrogen distribution in crop conservation. II—protein breakdown during wilting
Authors: Macpherson H. T.
Published: November 2006

Considerable chemical changes take place during the wilting of a crop. Protein breakdown in the presence of sufficient moisture is very rapid and the extent of breakdown is influenced by the time taken in the removal of moisture, nitrogen equilibrium being reached at a dry‐matter content of 40–45%. Rapidly dried material shows little breakdown and its use as an alternative to silage is discussed.
Some organoleptic studies on bakery products
Authors: Coppock J. B. M. , Hulse J. H. , Todd J. P. , Urie A.
Published: November 2006

As the selection by taste of a particular food can vary from person to person it is only by studying statistically the ability to taste of a sufficiently large group of people that trends in preference can be detected. These studies, on a large heterogeneous industrial population in Scotland, indicate that it is possible for such a group to display a marked capacity to select certain bakery products according to the nature of their ingredients. For shortbread there was a significant ability to differentiate between the products containing butter and cake margarine. When 85%‐extraction flour was replaced by 72%‐extraction (white) flour in cake there was an increase in ability to differentiate between products containing cake margarine plus dried egg and those containing butter plus fresh eggs.

After it had been demonstrated that the group possessed powers of discrimination, a consumer‐preference study was made on breads prepared from flours of different extraction‐rates. The results showed that (1) by taste, breads prepared from 72%‐ and 80%‐extraction flours were almost equally ‘preferred’, whereas breads made from 82 1/2%‐ and 85%‐extraction flours were considerably less preferred, in that order, and (2) by appearance, bread prepared from 72%‐extraction flour was undoubtedly preferred to all other kinds examined. Similar studies were made on the preference for shortenings of various types in shortbread, the order obtained being (1) butter, (2) compound cooking fat and (3) cake margarine. It is important to note that persons possessing a significant ability to taste showed a marked preference for products of high quality. There was no evidence to show that smokers and persons possessing dentures were appreciably inferior in their ability to taste.
Stability of contact insecticides. III—allethrin, DDT and BHC in ultra‐violet light
Authors: Blackith R. E.
Published: November 2006

Allethrin, the (±)allylrethronyl ester of (±)trans‐ and (±)cis‐chrysanthemic acids, is more stable to ultra‐violet photolysis than the natural pyrethrins. It is less well protected by benzeneazo‐β‐naphthol, so that the natural and synthetic insecticides have a similar stability in protected films.

DDT decomposes in oil solution at almost the same rate as the pyrethrins when irradiated by ultra‐violet light, and is also protected to a similar extent by benzeneazo‐β‐naphthol. DDT, the pyrethrins, and benzeneazo‐β‐naphthol all absorb ultra‐violet light strongly at about 2200–2400 Å. Some alleged DDT synergists were investigated, but no synergistic effect was detectable with the assay system used.

BHC is stable to ultra‐violet irradiation, as is expected from its formation from an irradiated chlorine‐benzene mixture.
The properties of the algal chemicals. I.‐the evaluation of the common british brown marine algae as a source of alginate
Authors: Black W. A. P. , Cornhill W. J. , Dewar E. T.
Published: November 2006

An investigation has been carried out to evaluate the common brown algae indigenous to Great Britain as a source of alginate. In particular, the viscosity of the sodium alginate from each species has been examined, and the effect on the viscosity of drying and bleaching has been studied. In an attempt to show that the alginates from the different species are essentially the same, specific rotations have been determined.
Effects of soil cultivation on the growth and yield of winter wheat. V—effects of cultivation on the nitrogen uptake and growth of crop in unfertilized and fertilized soils
Authors: Singh Khazan
Published: November 2006

1. Cultivation experiments were conducted for two years on four soils in the Midlothians, differing markedly in fertility and other physical and chemical conditions.

Cultivation treatments consisted of ploughing to a depth of 8 in. and shallow and deep cultivation with a tined cultivator to depths of 2 and 4 in. respectively.

2. The crop removed greater amounts of nitrogen and produced greater growth and greater yields in the ploughed plots than in the tine‐cultivated soil in the unfertilized plots of two of the soils. When the plots were manured the differences between the cultivation treatments disappeared in the richer soils but persisted between ploughing and one or both types of tine cultivation in poor soils, according to the fertility status of the soil.

3. The type of cultivation affected the vegetative growth of the crop more than the grain production in the unfertilized plots of the richer soil: straw/grain ratios differed significantly, varying from 1.53 for deep ploughing to 1.42 and 1.35 for deep and shallow tine‐cultivation respectively; the grain yields, however, showed no significant difference due to cultivation treatment.

No such cultivation effects on straw/grain ratios were apparent in the poor soil.

4. The response of the crop to nitrogenous fertilizer varied with the type of cultivation; in the tine‐cultivated plots, it was twice as great as in the ploughed plots, indicating a greater nitrogen deficiency in the cultivated plots. Factors contributing to this are discussed.

5. The level of fertility of a soil seemed to be the determining factor in its response to different types of cultivation. In a well drained and fertile soil, tine‐cultivation to a depth of 4 in., but not to a depth of 2 in., could replace ploughing if an application of nitrogen fertilizer was made to counteract the deficiency in nitrogen.
The selective staining of intact and damaged starch granules by safranin o and niagara blue 4B
Authors: Baker Frank , Hobson P. N.
Published: November 2006

A rapid differential‐staining method for distinguishing damaged from whole starch granules is described. The method has been applied to plant starches of different origins and to starches damaged by mechanical and chemical means. A relationship is shown to exist between the number of damaged granules, as shown by selective staining, and the susceptibility of the starch to enzymic hydrolysis.
The effects of methoxy‐p‐benzoquinone and some related compounds on bread quality
Authors: Greer E. N. , Halton P. , Hutchinson J. B. , Moran T.
Published: November 2006

Following the identification of (I) methoxy‐p‐benzonquinone and (II) 2:6‐dimethoxy‐p‐benzoquinone in the chloroform extract of yeast‐fermented wheat germ, the bread‐improving properties of natural and synthetic preparations of these compounds have been studied. A positive effect of (I) on loaf volume and an adverse effect of both on loaf colour have been found. Preliminary feeding trials on rats have shown no toxic effects at five times the levels of (I) which might occur in over‐fermented wholemeal bread.

Examination of a range of quinoids has revealed some capable of improving loaf volume but none free from adverse effect on colour which is probably due to chemical instability.
Studies on the blood proteins of hyperimmune horses. III.—The distribution of antibodies to Clostridium welchii type B
Authors: Harms A. J.
Published: November 2006

The antibodies present in various globulin fractions prepared from the blood of horses hyperimmunized with filtrates from Clostridium welchii type B have been estimated. Some observations on the distribution of the various antitoxins are made.
The determination of caffeine
Authors: Harris F. J. T.
Published: November 2006

Very many modifications of the basic method for the determination of caffeine in coffee products have been proposed from time to time. In a search for a rapid and reliable method all the steps and many alternative procedures have been considered. As a result, a method is now described which, although presenting few novel features, meets all the requirements and gives results of better‐than‐average accuracy. The accuracy of the method has been proved by checking actual manufactures.

Caffeine can be extracted from a solution‐buffered with trisodium phosphate, and determined by a Kjeldahl digestion. Zinc ferrocyanide is a satisfactory clarifying agent, provided that it is removed by filtration within, say, 15 minutes.

The accuracy of the proposed method is approximately 1% from the recovery experiments. A number of experimental batches of coffee and chicory essence were examined, and satisfactory agreement was found between calculated and determined caffeine contents.
The water‐soluble carbohydrates of grasses. II. —Grasses cut at grazing height several times during the growing season
Authors: Waite R. , Boyd J.
Published: November 2006

Four perennial grasses were cut with a motor mower each time they reached a height of about 8‐10in. during the growing seasons of 1951 and 1952. The water‐soluble carbohydrates, glucose and fructose (reported together as free hexoses), sucrose and fructosan were determined in each cut. Grasses in which the growing point had recently changed to a floral development (in May or June) contained more carbohydrate than grass grown and cut later in the season. The primary reason for this was that the later grasses were more leafy, and, secondly, that their stems contained much less fructosan than those of the earlier cuts.
Studies on egg shells. I.—The determination of membrane‐, pore‐ and matrix‐protein
Authors: Tyler C. , Geake F. H.
Published: November 2006

The protein in egg shells consists of the matrix‐protein closely associated with the mineral matter, the protein in the pores and a thin cuticle on the outside. In addition, the shell membranes are usually considered under the same heading although, strictly speaking, they are not part of the shell. A method has been devised by which the shell‐plus membrane‐protein can be divided into three distinct entities, by making use of the different rates at which these entities dissolve on boiling with sodium hydroxide solution. The method is arbitrary, and thus not absolutely accurate, but it appears to give a measure of entities which probably represent (1) membrane‐ and cuticle‐ (2) pore‐ and (3) matrix‐protein.
A new method for assay of the ‘pyrethrins’
Authors: Mitchell Wm.
Published: November 2006

A new method for assay of ‘pyrethrins’ is described. It is suggested that its successful operation requires less experience than do the existing methods. Comparative results on pyrethrum flowers and extracts by the new method and the A.O.A.C. (Association of Official Agricultural Chemists) method are given. A comment is made on the standard of accuracy to be expected from pyrethrum analyses in general.
Residues of tetrachloronitrobenzene on ware potatoes
Authors: Wilson A. R. , Dawson J. A.
Published: November 2006

Polarographic determinations have been made of 2 : 3 : 5 : 6‐tetrachloro‐1‐nitrobenzene (TCNB) residues on ware potatoes treated in autumn with 10 lb./ton of 3% TCNB dust to reduce sprouting in clamp. Results indicate that after normal commercial grading and transport following 4‐5 months' storage, concentrations of TCNB on tubers are likely to be about 2 p.p.m. When the storage period is increased to 6 months, a further reduction to approximately 1 p.p.m. is probable. The original concentration applied (134 p.p.m.) is reduced mainly by handling before and after clamping, but losses by evaporation have been shown to occur during storage. Washing still further reduces residues and no TCNB at all was found in the flesh of peeled tubers.
Through‐circulation drying of seaweed III.—Laminaria digitata frond and stipe; Laminaria saccharina frond
Authors: Gardner R. G. , Mitchell T. J.
Published: November 2006

The drying characteristics of Laminaria digitata frond and stipe have been studied and are compared with those of L. cloustoni frond and stipe.

A striking similarity was found in the shapes of the curves of time versus air velocity for the fronds and stipes respectively of the two species. The empirical equations for fronds were similar in type and those for the stipes were also similar. It was concluded that the physical differences between the two parts of the same plant had a greater influence on the drying time than the differences between the three common sublittoral species.

The close agreement between the species was most marked in the effect of bed depth on the drying time. This relationship was apparently independent of any particle‐shape factor since fronds (either minced, shredded, pre‐dried or wet) gave the same general type of curve, i.e. concave upwards. The bed‐depth curves for minced or sliced stipe were in general agreement, but were in contrast with the frond curves.

These physical properties of stipes and fronds have been compared with those of other vegetable materials (hops, potatoes, carrots and brewer's spent grain) and it has been shown that the time versus bed‐loading curves for all these materials can be classified into three groups, depending on whether the material is compressible or rigid.

The output versus bed‐loading curve for the first group (materials similar to fronds) reaches an optimum value, and mathematical considerations have demonstrated that the optimum drying time is about twice the minimum time. The minimum time for through‐circulation drying is the period required to dry a single layer of the material, and is represented by the intercept of the smooth curve (of time versus bed‐loading) on the time axis.

The effect of agitation on the reduction of drying time was investigated for two‐inch beds of L. digitata frond. Agitation was carried out at equal time‐intervals and has been expressed as effective stages. In the first half of the run (T = 7 to T = 3, where T = total water content, lb. of water/lb. of bone‐dry solid) three effective stages reduced the time to only 95% of the corresponding static time, whereas a reduction to about 40% was obtained in the range 3 to 0.1.

Bed‐depth experiments suggest that L. digitata plants dry faster than, and L. saccharina slower than, L. cloustoni. Internal temperatures of a 1/8‐in. slice of L. cloustoni stipe during a drying run have been measured. The effect on drying time of storage between harvesting and drying has been found for L. digitata frond.
Stability of contact insecticides. IV.—Relationship between the ultra‐violet absorption spectrum and the photolysis of DDT and the pyrethrins
Authors: Nasir M. Maqsud
Published: November 2006

The ultra‐violet photolysis of DDT and the pyrethrins was investigated with selected wavebands in the middle and near ultra‐violet. Severe decomposition is caused by light strongly absorbed by both insecticides at 2200‐2400 Å. DDT is not affected by other parts of the spectrum, but the pyrethrins are slowly decomposed by radiation between 2400 Å and the visible region, probably by a light‐catalysed oxidation rather than direct photolysis. DDT, like the pyrethrins, undergoes rapid photolysis in strong sunlight, suggesting that traces of light of the waveband 2200‐2400 Å may penetrate to the earth's surface.
Manuring of grassland. I.—Some effects of heavy dressings of nitrogen on the mineral composition of grassland herbage
Authors: Stewart A. B. , Holmes W.
Published: November 2006

Results are given for the effects of heavy dressings of nitrogen, in the presence and absence of phosphorus and potassium supplements, on: dry‐matter yield; botanical composition of herbage; contents of crude protein, phosphorus, potassium, calcium, magnesium, sodium and manganese. Brief reference is also made to the effects of the various experimental treatments on the uptake of certain other trace‐constituents.

The results indicate that high yields of pasture herbage having high protein and normal mineral contents can be maintained over a period of years by the use of fertilizer nitrogen, provided adequate fertilizer dressings of other major nutrients are given. Attention is drawn to various ion‐antagonism effects that may influence the mineral composition of the herbage.
Bottled and canned fruit: Studies of processing requirements and fuel consumptions by domestic methods
Authors: Crang Alice , Sturdy Margaret
Published: November 2006

The rates at which heat penetrates through fruit during preserving by bottling and canning have been studied by six different domestic methods. Determinations have been made of the processing times and temperatures required to give adequate control both of the spoilage micro‐organisms at the different pH levels found, and of the oxidase‐enzyme activity in the fruits having light‐coloured flesh. The quantities of gas or electricity used in preserving 1 lb., 5 lb. and 10 lb. of fruit, in the higher and lower pH ranges, have been recorded for each method, both for the initial and for the subsequent processes.
Fumigation of agricultural products. VI.—Penetration and sorption of hydrogen cyanide in wheat fumigated at reduced pressures
Authors: El Nahal A. K. M.
Published: November 2006

The penetration of hydrogen cyanide into bags of wheat of different moisture contents has been determined. Three methods of fumigation have been used : sustained‐vacuum fumigation, vacuum fumigation with simultaneous admission of air and fumigant, and fumigation at atmospheric pressure. Both the changes of concentration with time and the residual fumigant in the wheat were determined, and the relationships between these two quantities were investigated by means of a covariance analysis.

The method of vacuum fumigation with simultaneous admission of air and fumigant gives penetration and residues of fumigant similar to those obtained at atmospheric pressure. Sustained‐vacuum fumigation is superior to the other two methods over the same exposure periods, but the enhanced penetration of the mass of grain may be accompanied by a disproportionately higher sorption of fumigant. Sorption is increased considerably on wheat of higher moisture contents.
The relationship between the constitution and the effect of chemical compounds on plant growth. VI.—some derivatives of fluorene
Authors: Jones R. L. , Metcalfe T. P. , Sexton W. A.
Published: November 2006

Geotropic and phototropic responses of seedlings of rape, wheat and rye‐grass are inhibited by 9‐fluorenol‐9‐carboxylic acid and certain of its substituted derivatives. The antitropic effect of these and other acidic aromatic substances is discussed, and it is suggested that they may act through a competitive interference with the lateral transport of β‐indolylacetic acid.
Seasonal variation in the quality of grass silage
Authors: Smith A. M.
Published: November 2006

A study of the analytical results obtained with 1244 samples of silage, examined for advisory purposes during four seasons, has shown interesting relationships between dry matter, crude protein and pH values, and the influence of summer rainfall on these properties. A dry season tends to give a large proportion of samples that have a high dry‐matter content and a low protein content and pH, whereas the converse holds good for a wet season. The results indicate that the best conservation is secured with herbage containing more than 20% of dry matter.
Effect of insect infestation on stored grain. I.—studies on soft wheat
Authors: Pingale S. V. , Rao M. Narayana , Swaminathan M.
Published: November 2006

Soft wheat, which is considered to be easily susceptible to insect damage during storage, was subjected to infestation by three species of insects, namely Calandra oryzae L. (weevils), Trogoderma granaria E. (khapra beetles) and Ephestia cautella W. (almond moth), and the changes brought about by them are reported. The results suggest that, although weevils cause heavy reduction in the weight of the grain, the moth, which feeds only on the germ portion, considerably reduces the grain's viability. The results of an investigation on the degree of unhygienic conditions brought about in the grains by the addition of impurities and body fragments of the insects have been presented. An increase in the acidity of fat, and a decrease in the thiamine content due to insect damage, were both appreciable, but the effect on other constituents of the grain, such as total nitrogen and reducing sugars, was not significant.