bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of fumigants. XXI.—Preliminary experiments on the sorption of mercury vapour by wheat
Authors: Gorringe B. S.
Published: November 2006

An ultra‐violet absorption method for the determination of mercury vapour in air is described. The apparatus incorporates a special ultra‐violet filter. The amount of mercury vapour sorbed by clean pyrex glass was found to be small compared with that sorbed by wheat, and to have no relation to the time of exposure. The sorption of mercury vapour by English wheat of moisture content 13–18% at temperatures of 20–30°C. has been studied. It is concluded that most of the mercury sorbed is firmly retained by reaction with the wheat tissues.
The determination of water in sugar solutions by oven‐drying
Authors: Mitchell Thomas J.
Published: November 2006

In a study of the factors influencing the determination of water in thermally sensitive substances by oven methods, solutions of sucrose, glucose and fructose have been dried in the steam oven and in the vacuum oven using various dishes, absorbents, times, temperatures and PH values.

It is shown that fructose solutions cannot be dried without decomposition in the steam oven, whereas glucose is relatively stable at 98° C. Sucrose solutions dry very slowly and are reluctant to give up the last traces of water. In general there is faster drying in the acid zone of the pH scale, with slow drying and greater tendency to decomposition in the alkaline region.

When drying is carried out on paper rolls it is found that fructose gives low results, corresponding to the Joss of half a molecule of water of crystallization: normal results are given by sand, pumice or Celite absorbent under the same conditions.
Some present trends in baking research
Authors: Coppock J. B. M.
Published: November 2006

The effect on food science of the recent rapid developments in the chemical industry is discussed, particularly from the aspect of the potential physiological effects that may result from the use of new materials in food processing. The need for studying the toxic properties of many new chemical compounds and their role in human nutrition is emphasized, and it is thought that suitable limits governing their use will need to be prescribed as has already been done for elements.

Chemical substances may be used in three main ways: (i) included as ingredients, (ii) used for facilitating processing operations and (iii) in the improvement of hygiene. Pharmacological data required will include studies on (a) absorption, (b) metabolism and (c) acute and chronic toxicity. It is thought that diverse methods of approach to these problems should be made, and in many cases the classical methods of analytical chemistry will supplement and fortify data obtained by the pharmacologist. In certain cases where the chemist can demonstrate that substances are not absorbed during processing chemical data alone may suffice.

These views are illustrated by considering examples of (i), (ii) and (iii) above, with particular reference to the baking industry.

The need for greater knowledge in this undeveloped avenue of research in food science is strongly emphasized.
The ultrafiltration of clay suspensions
Authors: Wild A.
Published: November 2006

A description is given of a modified form of Bechhold apparatus which has been used to ultrafilter 0.2% clay suspensions in the course of work on the retention of phosphate by clay. The suspensions are forced under pressures of 60–80 lb./sq. in. through membranes made from collodion dissolved in glacial acetic acid. The membranes retain up to 3–4% of the phosphate present in standard solutions, the loss decreasing with increasing pH value. It is shown that this reduction in phosphate concentration is not affected by clay. The concentration of phosphate in the solution of a clay suspension can therefore be determined from the concentration of the ultrafiltrate by using the small correction factors found with standard solutions.
An examination of polymerized pyrethrins
Authors: Campbell A. , Mitchell Wm.
Published: November 2006

The resinous material formed by polymerization of a highly purified pyrethrum concentrate has been examined. It was insoluble in cold light petroleum or deodorized kerosene, and gave high values for apparent pyrethrins by the Seil or mercury‐reduction methods, although it was devoid of insecticidal effect on houseflies. In these respects it resembled the additional ‘pyrethrins’ recently shown1 to be extracted by chloroform or by warm light petroleum from pyrethrum flowers, differing only in its higher content of apparent ‘pyrethrin I’.

On hydrolysis of this material, pure chrysanthemum mono‐ and di‐carboxylic acids were isolated in yields of some 75% of the quantities calculated from the analysis. These acids were identical with those derived from normal pyrethrum extracts. Hence it appears that polymerization is confined to the keto‐alcoholic constituents of the esters, the acids not being involved. The chemical assay methods at present available do not distinguish such polymerized material from true pyrethrins; but the modification described by Mitchell and Tresadern1 largely prevents the extraction of polymerized material.

The need for confirming all chemical assays by biological tests is emphasized. A portion of the monocarboxylic acid was esteri‐fied with DL‐allylcyclopentenolone; the ester possessed the expected insecticidal activity. The action of this ester on houseflies is discussed and contrasted with that of the pyrethrins.
Changes in composition of cottonseed during development and ripening
Authors: Grindley D. N.
Published: November 2006

Analyses have been made of cottonseed (Gossypium hirsutum) at different stages of maturity after flowering, and the results have been recorded in tables and graphs. It is seen that no appreciable oil develops in the seed until about the 35th day, when it increases rapidly; the carbohydrates decrease over this period. The oil as first formed is highly acidic, and contains much unsaponifiable matter, although the composition of the fatty acids remains practically constant over this period. The protein and ash contents increase steadily more or less in proportion to the weight of seed, but the crude fibre shows a sharp increase shortly before full maturity is reached. The immature seeds yield oil which does not respond to the Halphen test.
Analysis of undried pyrethrum flowers
Authors: Edwards M. G.
Published: November 2006

A method, suitable for practical laboratory application, of quantitatively extracting undried pyrethrum flowers is described. The flowers are ground with the solvent in a porcelain mill, the solution washed out with more solvent and the bulk of the water removed from the marc by distillation in solvent vapour. The residue is then reground and re‐extracted, when it is almost completely exhausted, and the combined extracts are evaporated; they may be assayed by conventional methods.
The concentration of tocopherols from natural sources by molecular distillation
Authors: Green J. , Watt P. R.
Published: November 2006

A laboratory model cyclic falling‐film molecular still has been constructed and has been used to prepare mixed tocopherol concentrates from various seed oils. The choice of an oil for preparing a concentrate of a particular potency is discussed.
Potentiometric analysis of bromide‐chloride mixtures at low concentrations. Application to fumigant mixtures
Authors: Winteringham F. P. W. , Bridges R. G. , Harrison A.
Published: November 2006

The potentiometric method of Northrop for the determination: of chlorides using a simple galvanometer circuit was studied as being suitable for possible extension to the analysis of bromide‐chloride mixtures. The silver electrode potential at the stoichio‐metric bromide equivalence‐point in dilute bromide‐chloride solutions was determined. The results obtained were most satisfactorily accounted for on the basis of co‐precipitation, the silver chloride fraction behaving independently and not necessarily as a mixed crystal. By using two reference cells which duplicate the silver electrode potential, one at the total halide equivalence point, and the other at the bromide equivalence point in an excess of chloride, the analysis of dilute mixtures can be made using a simple galvanometer circuit. The methods have been successfully applied to the analysis of low concentrations of methyl bromide fumigant mixtures after decomposition in ethanolamine.
A simple tissue homogenizer
Authors: Marsh B. B. , Snow A.
Published: November 2006

A disintegrator capable of very rapidly breaking up muscle tissue in the presence of enzyme inhibitors or other liquids is described.
Dried albumen: Removal of sugar by yeast before drying
Authors: Hawthorne J. R.
Published: November 2006

A procedure for preparing stable dried albumen is described. The egg white, before drying, is freed from the naturally occurring glucose by yeast fermentation and from yeast by centrifuging. Laboratory tests showed little or no difference between the best experimental samples and samples of commercial, bacterially fermented albumen. This result was confirmed by tests carried out under commercial bakery conditions.
Factors affecting the uptake of phosphorus by plants
Authors: Smith A. M. , Simpson K.
Published: November 2006

A study has been made in a series of 16 field experiments of the recovery by the turnip crop of the phosphorus applied in various phosphatic fertilizers, superphosphate at two rates (0.33 and 0.66 cwt. P2O6 per acre) being used as a standard. The recovery of phosphorus varied from less than 5 to almost 40%; it was nearly always greater from superphosphate than from other fertilizers and it was nearly always greater from the low than from the high rate of phosphate application. The soil properties which were most closely related to the percentage recovery were exchangeable calcium and citric‐soluble phosphate, the correlation coefficients being slightly above and slightly below the 2% level of significance respectively. These soil properties were quite unrelated to each other. Summer rainfall was also found to exert a considerable influence on the recovery of the phosphorus added; the partial correlation of recovery and exchangeable calcium, eliminating summer rainfall, reached the 1% level of significance.
The fate of labelled insecticide residues in food products. I.—Studies with a radioactive bromine analogue of DDT
Authors: Winteringham F. P. W. , Harrison A. , Jones C. R. , McGirr J. L. , Templeton W. H.
Published: November 2006

A radioactive bromine analogue, 1:1:1‐trichloro‐2:2‐di‐(4‐bromophenyl)ethane, of the insecticide DDT has been used to indicate the fate of DDT sprayed on to wheat grain which is subsequently milled, baked and fed to animals. 82Br of high specific activity was prepared in the Harwell pile by the Szilard‐Chalmers method and was used for the synthesis of the analogue. Grain carrying 402 p.p.m. of the labelled insecticide was milled under typical conditions. A concentration of 14.6 p.p.m. was found in the flour (85% extraction) and 11.2 p.p.m. in bread made from the flour. There was evidence that some of the insecticide was in a ‐combined form in the bread. Some of the grain and bread were fed to hens and rats respectively. The insecticide was found in all the tissues examined. A fraction of the radioactivity found in the excreta behaved as the di‐(4‐bromo‐phenyl)acetic acid metabolite. This metabolite was identified in the urine of a man following ingestion of some of the bread.
Dried‐grass meal as a riboflavin supplement to animal feeding stuffs with special reference to poultry
Authors: Brown W. O.
Published: November 2006

The need for riboflavin in animals is discussed and the literature relating to the riboflavin content of grasses and other forage crops is reviewed. Results are given of the riboflavin and the crude protein content of a number of commercial dried‐grass meals; from these results it is shown that the crude protein content of dried‐grass meal may be used as an approximate index for its riboflavin value.

The results of a biological test with chicks designed to secure evidence of the value of dried‐grass meal as a riboflavin supplement is reported. Using the riboflavin content of the liver and the incidence of curled‐toe paralysis as essential criteria for the demonstration of adequate riboflavin nutrition, a level of 10% of good‐quality dried‐grass meal containing about 16 μg./g. is shown to be necessary to give optimum results for the healthy growth of chicks.
Anthrone as a reagent in fluorescence analysis, and some applications
Authors: Radley J. A.
Published: November 2006

A reagent consisting of anthrone dissolved in concentrated sulphuric acid has been found to develop characteristic fluorescence colours in filtered ultra‐violet light when heated with low concentration of a number of organic compounds. Glycerol and glycol derivatives are especially reactive, and so is tartaric acid. The reaction has the delicacy of a ‘micro’ test and several instances of its use for identification of specific compounds in industrial forensic and foodstuff investigations are given.
The component fatty acids of tobacco‐seed oils
Authors: Crawford R. V. , Hilditch T. P.
Published: November 2006

The component acids of tobacco‐seed oils from plants grown in India, Turkey, Rhodesia and England have been studied: the linoleic acid content varied from 69% (Indian) to 79% (English). The glycerides of the Indian oil were studied and shown to include about 74% of dilinoleo glycerides and 20% of trilinolein. This composition indicates the suitability of the oil as a non‐yellowing oil for paints, alkyd resins, etc., and also shows that tobacco‐seed oils follow the usual pattern of seed‐fat glyceride structure. All the oils studied are thus very suitable for the paint industry (this finding has been confirmed by practical usage in the case of Indian oil), but earlier records suggest that, as in sunflower and some other species, the proportions of linoleic and oleic acid may vary over a much wider range.

In view of this variability and of the fact that any oil with a linoleic content of more than about 67% is well suited for drying purposes, the technical designation of oils with linoleic contents of 67% or higher from any of these sources as ‘linoleic‐rich (tobacco) seed oil,’ ‘linoleic‐rich (sunflower) seed oil,’ etc., is suggested.
The enzymic degradation of pectin and other polysaccharides. I.—Introduction, and a preliminary study, on the degradation of the polysaccharides of fruits by the enzymes produced by micro‐fungi (‘moulds’)
Authors: Reid W. W.
Published: November 2006

The polysaccharidases occurring in enzyme preparations from micro‐fungi, and used in the commercial processing of fruit products, have been examined. It has been shown that the majority of the preparations and cultures of micro‐fungi examined produced enzymes capable of degrading polygalacturonic acid, araban, galactan, xylan, etc. The occurrence in fruits of a mixture of polysaccharides and the presence of the appropriate hydrolases in the enzyme preparations raises certain difficulties in the standardization of these preparations for technological use. In addition, the estimation of the glycosidic hydrolysis of pectin produced by such preparations will consist of the total hydrolysis of polygalacturonic acid, araban and galactan; the assay of polygalacturonase activity by estimation of glycosidic hydrolysis may consequently be inaccurate.

The simultaneous degradation of these three polysaccharides in relation to glycosidic hydrolysis, the secondary change in colloidal properties and the structure of pectin, is discussed. Evidence is presented suggesting that the enzymic hydrolysis of pectic acid occurs in two stages, which may be due to separate enzyme actions : the hydrolysis of araban and galactan, and the hydrolysis of polygalacturonic acid. The use of enzymes as analytical tools in the examination of pectin is indicated, and emphasis is laid on the desirability of preparations having a single enzyme activity.
Phosphate fixation and availability
Authors: Williams E. G.
Published: November 2006

Factors that may affect the relation of fixation to availability are briefly reviewed. A preliminary assessment of this relationship for superphosphate added to some typical acid soils in N.E. Scotland is made from solubility data on the rate of fixation, the effect of time of application, and the residual value of phopsphate dressings as measured by field and pot experiments.
South african fish products. XXXI.—The composition of pilchard oil and of maasbanker oil
Authors: Black M. M. , Schwartz H. M.
Published: November 2006

A quantitative study of the saponifiable and unsaponifiable fractions of three samples of South African Pilchard oil and of one sample of maasbanker oil has been made.

Differences in the iodine value of the three pilchard oils studied resxulted chiefly from differences in the mean unsaturation of the various homologous groups of fatty acids, the relative proportions of the different groups differing c comparatively little in oils of high and low iodine value. In the oil from the very lean fish the percentage of c22 Acids was increased at the expense of the plamitc and c18 unsturated acids, an observation which supports Lovern's view that in fasting fish the acids of lower molecular weight are preferentially utilized leading to an accumulation of acids of high molecular weight.

Maasbanker iol differed from pilchard oil in that the percentage of C20 unsaturated acids was lower and the percentage of C22 unsturated acids was highere than in pilchard oil. A more striking difference was the lower degree of unsturation of both the C20 and C22 acids in the maasbanker oil; this was reflected in its very much lower iodine value.

Cholesterol was the chief constituent of the unsaponifiable fraction of both pilchard and maasbanker oil. Other components of the unsaponifiable fractions of both oils were α‐glyceryl ethers, saturated and unsaturated hydrocarbons, fatty alcohols and vitamin A. Evidence was obtained that a C22 unsturated fatty alcohol was present in the unsaponifiable faction of maasbanker oil.
The component fatty acids of elephant seal oil: The distribution in the body
Authors: Winter G. , Nunn W. J.
Published: November 2006

The detailed analyses of blubber fats from three parts of the body of an elephant seal are reported. The similarity of the results show that there is reasonable uniformity in the distribution of the fatty acids throughout the blubber.
Changes in the sugar composition of coconut water during maturation and germination
Authors: Child R. , Nathanel W. R. M.
Published: November 2006

Changes in the sugar content of the water of the coconut have been followed during ripening and germination. From the most immature fruit in which the cavity has just formed to about the seven‐month‐old fruit when it is full size but still unripe, the sugars present, which are almost entirely reducing sugars, increase to a maximum of about 5% concentration. Thereafter non‐reducing sugars appear, but the total concentration of sugars fall to about 2% in the fully ripe nut, 12 to 13 months old.

The results were much the same in the three varieties of Coos nucifera L. studied—the ordinary tall palm, a dwarf variety, and a variety with orange‐coloured fruit, known in Sinhalese as Rath‐Thembili—expect that in the water of dwarf nuts small amounts of non‐reducing sugars were present in the earlier stages.

During the early stages of germination the concentraion of reducing sugars continues to fall, but that of total sugars remains fairly constant until the fourth month of germination, when it also falls.
Laboratory assessment of pectin quality with special reference to jelly grading
Authors: Olliver Mamie
Published: November 2006

Apparatus for testing strength is reviewed, attention being drawn to the different physical principles involved. The American definition of pectin jelly grade has been adapted to conform with English jam‐manufacturing practice, and the effect of different conditions of gel preparation is described. Rate of cooling and Ph are more important factors than type or quantity of buffer, and temperature of ageing and soluble‐solids content both exert considerable influence above Ph 3.0. Points are listed for consideration when formulating a laboratory procedure for jelly sideration when formulating a laboratory procedure for jelly grading. Methods of determining the rate of set are briefly described.
The vapour pressure of parathion and related compounds
Authors: Bright N. F. H. , Cuthill J. C. , Woodbury N. H.
Published: November 2006

In view of the widespread interest in insecticidal formulations based on parathion, the vapour pressures of the pure material and a number of related compounds likely to be encountered in the commercial product have been measured at various temperatures within the range 25–92° C. The materials examined include : (a) pure parathion, O,O′‐diethyl O‐P‐nitrophenyl thiophosphate, (b) S‐ethyl isomer of (a), O,S‐diethyl 0‐P‐nitrophenyl phosphate, (c) S‐phenyl isomer of (a), O,O′‐diethyl S‐p‐nitrophenyl phosphate, (d) commercial parathion, which contains mainly pure parathion together with small quantities of various related compounds, (e) O,O′,O″‐triethyl thiophosphate, (f) O,O′‐diethyl S‐ethyl phosphate, (g) O‐ethyl O,O′‐bis‐P‐nitrophenyl thiophosphate. Compounds (a) to (d) and (g) were examined by an effusion technique. Compounds (e) and (/) were examined in a liquid U‐tube manometer. Details of the preparation of the materials are given. The vapour pressures have been shown to be low at ordinary temperatures (generally of the order of 10−4 mm. mercury, or lower, at 20° C).

The data provided will be of use in assessing the toxic hazards of exposure to the vapour of parathion and related compounds, and the permanence of insecticidal deposits of the material.
Use of titan yellow for the determination of magnesium in plant material
Authors: Cornfield A. H. , Pollard A. G.
Published: November 2006

A modification of the colorimetric determination of magnesium by means of Titan yellow, as applied to plant‐ash extracts, is described, in which no preliminary separations are required; the range is from 10 to 80 μg. magnesium.
The examination of biscuit flour doughs by load‐extension tests
Authors: Halton P. , Greer E. N.
Published: November 2006

A study has been made of the characteristics of unfermented English wheat‐flour doughs as indicated by load‐extension tests.

The conditions of preparation of dough and the method of testing are described. The results of these tests have been compared with manufacturers' assessment of the biscuit‐making quality of the flour used. It is found that the most suitable flours possess the characteristics of low elasticity and high extensibility, and the limiting conditions, in terms of extensometer readings, for satisfactory biscuit flours are indicated. In two series, tests have been applied to a number of pure varieties of English wheat and it is shown that Little Joss is the most consistently suitable of those tested.
Spontaneous heating and ignition in stored palm kernels. II.—Reactions between palm‐kernel bag fat and gaseous oxygen
Authors: Burgoyne J. H. , Thomas A.
Published: November 2006

The reaction of oxygen at atmospheric pressure with dispersed palm‐kernel bag fat has been studied in the range of temperature 50 to 160°c., but principally at 80°c. and with the fat dispersed on glass surfaces, although the reaction with fat‐impregnated jute has also been studied comparatively. The relationships between oxygen consumption, product formation, total pressure change and heat evolution throughout the reaction have been established and the effects of the specific surface of the fat and the pressure of the oxygen on the reaction velocity have been studied. It appears that the oxygen initially attacks the linoleate present more rapidly than the oleate (which is in greater concentration); the linoleate consequently becomes exhausted first and the reaction rate is modified. The heat of initial reaction is about 59 kg.‐cal./mole. Observations on the formation of peroxide and the disappearance of double bonds during the reaction are discussed in the light of the modern views of Hilditch, Farmer and others on the mechanism of oxidation of unsaturated fats.
Spontaneous heating and ignition in stored palm kernels. III.—Steady‐state temperature distribution in a uniform mass of material subject to atmospheric oxidation: A uni‐dimensional treatment
Authors: Burgoyne J. H. , Thomas A.
Published: November 2006

On the basis of previously measured rates, rate‐temperature coefficient and heat of the reaction between oxygen and palm‐kernel fat, the steady‐state temperature distribution in uniform columns of palm kernels due to atmospheric oxidation is determined theoretically using a uni‐dimensional model. Temperature rise may be controlled by three factors; (i) conduction loss, (ii) oxygen deficiency and (iii) convection loss. In practice (i) and (ii) or (i) and (iii) usually operate together; however, they may be considered separately in order to define the lengths of column, external temperatures and ventilation rates at which the column is certainly safe from spontaneous ignition; but the margin of safety cannot be determined by this simplified method.
Spontaneous heating and ignition in stored palm kernels. V.—A study of the self‐heating of the palm kernels and the jute bags in the presence of moisture
Authors: Bowes P. C.
Published: November 2006

The range of self‐heating of the moistened materials of the palm‐kernels stack, under aerobic conditions and with known heat loss, has been explored. It has been concluded that the heating under these conditions is mainly due to the respiration of a micro‐flora developing on the materials.

No evidence has been found of a reaction, consequential to the biological reactions, which could continue the heating above the lethal temperature for the micro‐flora present in the palm kernels or in the jute bags contaminated with the palm‐kernel fat. If this is to occur the intervention of an anaerobic stage in the biological activity is likely to be essential.
Recovery of water‐soluble nutritional factors from fish livers
Authors: Gray D. J. S. , Novellie L. , Shuttleworth R. G.
Published: November 2006

Methods of processing hake livers whereby the protein fraction and the water‐soluble nutritional factors may be recovered in addition to the oil and oil‐soluble vitamins, have been examined. Methods involving (a) partial tissue digestion by papain, and (b) water‐extraction (under conditions involving some autolysis) have been compared. The water‐soluble fraction from process (b) has been subjected to evaporation under reduced pressure and to spray‐drying. The powder thus obtained has been analysed for nitrogenous components, glycogen, vitamins of the B group (including vitamin B12) and for fifteen inorganic elements.
Estimation of sterilizing values of processes as applied to canned foods. I.—Packs heating by conduction
Authors: Gillespy T. G.
Published: November 2006

The F value of a heating process as applied to a can of food is defined as the time in minutes at 250° F., assuming the whole can to be raised instantaneously to this temperature and cooled instantaneously to a sub‐lethal temperature afterwards, that would give the same degree of sterility as the process to be valued. The implications of the term ‘degree of sterility’ are discussed.

Equations are developed and tables are given, applicable to pure conduction packs only, for estimating the F value of a process for a small finite volume at the centre of a cylindrical can. Such a value has hitherto been used to represent the F value for the whole can. It is here designated the Fc value. The effects of the relative dimensions of the can, of pre‐processing procedures and of the coming‐up time of the retort are considered. The Fc value is independent of the absolute heat resistance of the organisms to be killed, assuming the same temperature‐time relationship.

A method is presented for estimating the F value for the whole can from the Fc value. The F value is shown to vary with the heat resistance of the organisms for which the degree of sterility attained is defined.
The availability of the nitrogen in some bone materials used in horticulture
Authors: Long M. I. E. , Owen O. , Winsor G. W.
Published: November 2006

The total nitrogen content of 16 commercial samples designated as bone meal showed a wide range of values from 2.12 to 5.55%. Samples of bone meal were added to soil in quantities equivalent to 300 p.p.m. nitrogen in each case, and the fraction of the total nitrogen readily converted to ammonia and nitrate was determined after incubation for nine days at 23.5° c.; these fractions so converted were significantly correlated with the percentage of the total nitrogen that was soluble in water. Significant correlations were also found with the bulk densities and sieve analyses of the milled samples, the pH of their aqueous suspensions, and the ammonia liberated on distillation with magnesia. The effect of different degrees of milling upon the results of the tests was examined for selected samples.
The component acids and glycerides of pentaclethra (Leguminosae) and lophira (Ochnaceae) seed fats
Authors: Hilditch T. P. , Meara M. L. , Patel C. B.
Published: November 2006

The seed fats of these West African species of plants contain 15–20% of saturated acids (mainly behenic or lignoceric) of higher molecular weight than stearic acid; the unsaturated acids are confined to oleic and linoleic in varying proportions. The composition of the mixed glycerides in the fats conforms closely to the usual ‘evenly‐distributed’ type. Although the fats are probably capable of use as supplementary sources of edible fats, the presence in appreciable proportions of behenic and/or lignoceric acid is disadvantageous either for edible purposes or, more especially, for soap making. In a specimen of deteriorated seed fat from Lophira alata, it was observable that the behenic acid present had proved relatively resistant to enzyme action.
Taint in potatoes grown on land treated with crude benzene hexachloride against wireworms
Authors: Jameson H. R. , Tanner C. C.
Published: November 2006

It is shown that the degree of taint produced in potatoes grown on land treated (worked into the soil by normal cultivation methods) with crude benzene hexachloride is a function of the amount of crude BHC applied per acre and the time elapsing after application. An equation linking degree of taint with these variables is given and summarizes data accumulated over a period of four years in numerous trials under varying soil and climatic conditions in England.

Potatoes grown after treating land with 4 lb. crude benzene hexachloride per acre for control of wireworm are likely to be tainted if planting takes place within r8 months of the date of soil treatment; if planting takes place three years after soil treatment the crop should be free from taint.
Photo‐decomposition of rotenone in spray deposits. II.—Laboratory technique for producing replicate deposits
Authors: Rao N. V. Subba , Pollard A. G.
Published: November 2006

A satisfactory method for producing in the laboratory replicate deposits of insecticides is worked out making use of a modified Potter tower and an aerograph nozzle. Various factors affecting deposition have been studied.
Equilibrium humidity of sugar solutions
Authors: Money R. W. , Born R.
Published: November 2006

As a result of studies of the equilibrium humidity‐concentration relationship of a number of solutions of sugars, an empirical formula has been derived relating the equilibrium humidity value with the molar concentration. The equation is of the same form as that derived from Raoult's law, but is applicable over a wide range of concentrations. An ‘equivalent molecular weight’ has been derived for the solids of glucose syrup, whereby this material may be considered in a similar manner to simple sugars. Examples are given of the application of the equation in the calculation of the equilibrium humidity values of jams, fondant creams and boiled sweets.
The availability of soil phosphate. I.—Examination of the soil solution with special reference to the fixation of phosphate
Authors: Yuen S. H. , Pollard A. G.
Published: November 2006

The effects of fertilizer treatments and of season on the constituents of the soil solution, with special reference to phosphate, have been examined, using soils tested as part of a long‐term fertilizer‐experiment.

The concentration of inorganic phosphate in the soil solution in phosphate‐treated plots was higher than that of the control throughout the year, the increases ranging from 21‐5 to 66.6%. The effect of superphosphate did not increase during cropping; the concentrations of inorganic phosphate in the soil solution were low in summer and varied very little through the year. Ammonium sulphate and lime reduced the inorganic‐phosphate concentration. In plots receiving dung the concentrations of inorganic phosphate were unusually high, the increases ranging from 120 to 635% in the 0–8‐in. soil layer. In the presence of lime the increases of phosphate due to dung were lower. There was no indication of the downward movement of phosphate through the soil.

The concentration of organic phosphorus in the soil solution decreased during the cropping season. Ammonium sulphate, superphosphate and potassium sulphate tended to increase the organic phosphorus in soil solutions but lime tended to reduce its accumulation in July. Dung did not increase the organic phosphate greatly, especially in the presence of lime.

Simple and partial correlations between inorganic phosphate and other constituents in the soil solution were studied. Inorganic phosphate examined in April was negatively correlated with both pH and calcium. The relationship with pH was most clearly observed in plots without phosphate treatment and that with calcium in the superphosphate‐treated plots. The relationship was unchanged when the correlation coefficients were calculated between phosphate and calcium with pH or nitrogen constant, and between phosphate and pH with calcium or nitrogen constant. There was no significant correlation in the July and September samples.

Colloidal absorption of phosphate appears to dominate the fixation of phosphate in the soil although there is evidence of chemical precipitation by calcium.
Applicability of the morgan test for determining available soil phosphate
Authors: Yuen S. H. , Pollard A. G.
Published: November 2006

An examination of the Morgan ‘quick’ test showed that the amount of phosphate extracted from soils increased with the widening of the ratio, soil/extractant, and with the period of extraction; the maximum extraction was obtained in most soils by shaking the soil with the extractant for I hr. Of the likely phosphorus‐bearing constituents of soil Morgan's reagent dissolves mainly calcium (and probably magnesium) phosphates; organic forms of phosphorus dissolve only to a small extent. In the soil examined, Morgan's test failed to distinguish the effect of 17 successive annual applications of superphosphate at the rate of 100 lb. per acre. However, it did detect, decisively, corresponding applications at the rates of 200 and 400 lb. per acre.

The Morgan test further demonstrated the depression of phosphate availability by repeated application of ammonium sulphate, the opposite effect of liming, the very substantial increase in availability after the application of dung, the absence of any effect of treatments with potassium sulphate and an apparent seasonal variation in phosphate status in the soil examined.
The ovicidal activity of some phenyltrichloromethylcarbinols and their esters towards eggs of the glasshouse red spider mite (Tetranychus telarius L.)
Authors: Read W. H. , Wain R. L.
Published: November 2006

Although numerous investigations have been directed towards relating chemical structure to insecticidal activity, little work of this type has been carried out with ovicides. This paper describes the results of ovicide tests using some phenyltrichloromethylcarbinols and their esters against eggs of Tetranychus telarius L.

The laboratory method employed for assaying ovicidal activity, which was developed at the Cheshunt Research Station, is described.

4‐Chlorophenyltrichloromethylcarbinol and its acetate were the only compounds showing appreciable ovicidal action, but the following relations between ovicidal activity and chemical constitution were indicated by the results: (a) toxicities of phenyltrichloro‐methylcarbinol and its esters are increased by the introduction of C1— and, to a lesser degree, of CH3— into the para‐position of the ring; (b) the ovicidal activity of the carbinols is reduced by esterification; (c) the 4‐chlorobenzoates appear to be more toxic than the corresponding 4‐nitrobenzoates, but less toxic than the acetates.
The availability of soil phosphate. II.—Comparison of extraction methods
Authors: Yuen S. H. , Pollard A. G.
Published: November 2006

Comparison is made of the Dyer, Truog and Morgan tests for available phosphate in soils using long‐term fertilizer trial plots. All three tests recorded the cumulative effects of annual applications of superphosphate and the more marked effects of dung; however, the actual values indicated by the tests differed. The Truog and Morgan methods, but not the Dyer test, reflected the depressive effect of ammonium sulphate and the beneficial effect of lime on phosphate availability. Test data are compared with the recovery of phosphate by a flax crop. A seasonal variation in the available phosphate in soil was indicated, notably by the Morgan and Truog tests: it was more marked in plots receiving annual dressings of superphosphate than in those receiving dung, untreated controls occupying an intermediate position in this respect.
The fatty acids and glycerides of okra seed oil
Authors: Crossley A. , Hilditch T. P.
Published: November 2006

The component acids and glycerides of okra seed oil (iodine value 94.0, free fatty acid 0.1%, unsaponifiable matter 1.2%) from the Sudan have been investigated. The acids comprised palmitic 23.8%, stearic 7.4%, oleic 27.1% and linoleic 41.7% (wt.). The glycerides included about 40% of saturated‐oleo‐linoleins, 25% of triunsaturated glycerides (mainly oleodilinolein), 10% of saturated‐dilinoleins and 23% of glycerides containing two saturated acid groups with either an oleic or a linoleic group.

The oil is very closely similar in constitution to cottonseed oil and, providing the harvesting of the seed and its subsequent decortication present no insuperable difficulties, it should be completely suitable for all uses to which cottonseed oil is put.
The determination of lactic acid in milk
Authors: Ling E. R.
Published: November 2006

A rapid method for the determination of lactic acid in milk is described.

After precipitation with NaOH‐ZnSO4 in the presence of BaCl2, the filtrate is treated with FeCl3‐HCl reagent, and the colour is measured by one of the three common methods. Reference to standard curves prepared from similar observations on lactic‐treated fresh mixed milk enables lactic acid to be determined with an accuracy which compares favourably with the p‐hydroxydiphenyl method.

The approximate lactic content may be determined by adding to the filtrate a mixture of ferric chloride, potassium ferrocyanide and salicylic acid solutions.

Although the apparent lactic content of fresh mixed milk is 0.003%, advanced lactation may cause considerable increases in this value.
Oxidation in apple juice. III.—Oxidation turbidities
Authors: Marshall C. R.
Published: November 2006

Hydrogen peroxide has been used as a reagent for studying oxidation turbidities in bottled apple juice. The extent of sediment formation is dependent upon concentration of both dissolved oxygen and of an oxygen acceptor which is probably tannin, since juices with high tannin contents throw heavier deposits than others. Prolonged storage in bulk before bottling and heat treatment by pasteurization reduce the volume of deposit in bottle. Ascorbic acid added as an antioxidant is only slightly effective in controlling oxidation turbidities. The role of dissolved oxygen in apple juice is discussed at some length.
The cultivation and analytical data of blackcurrants and raspberries in Tasmania
Authors: Hill H. E.
Published: November 2006

A description is given of the berry fruit‐growing industry in Southern Tasmania. The methods of harvesting and conditions of transportation are described. Analyses of blackcurrants and raspberries, made during the 1948, 1949 and 1950 seasons, are presented with a view to providing information of assistance in determining the amounts of these fruits in pulps and jams.
Distribution of carotenoids in different parts of the carrot
Authors: Booth V. H.
Published: November 2006

The concentration of total carotenoids in various sections of the root of the carrot was studied by extracting the fat‐soluble yellow pigment and estimating it colorimetrically. The concentration had a general fall longitudinally from crown to tip although there was a small increase just beyond half‐way. The side roots and the ‘rat‐tail’ root had relatively very low concentrations of carotenoids.

The pigmentation of xylem was always less, and varied much more, than that of the phloem but the two were positively correlated. Carotene comprised about 70% of the total carotenoids in the xylem and this percentage was positively correlated with depth of pigmentation. The concentration of carotenols in xylems of different carrots was much more nearly constant than that of carotene.
The corrosion‐resistance of stainless steels towards citrus fruit‐squash concentrates and towards citric acid‐sugar‐common salt‐sulphur dioxide solutions
Authors: Bryan J. M. , Selby J. W.
Published: November 2006

This research was undertaken to determine the relative suitability of a range of Austenitic stainless steels for use in equipment for handling hot citrus fruit concentrates containing sulphur dioxide. The work was carried out as two parallel investigations in separate Laboratories using, as corroding agents, in one Laboratory a hot solution of citric acid, sugar, common salt and sulphur dioxide, and in the other, natural citrus fruit concentrates containing sulphur dioxide.

It is shown that the steels which contained from 2% to 3% of molybdenum were much more resistant to both these agents than were similar steels which did not contain this element. It is reasonable to suppose that the molybdenum‐bearing steels would give satisfactory service in the citrus juice industry, and this opinion has been confirmed by further tests under factory conditions.

It is noted that the use of welding in the fabrication of stainless‐steel equipment frequently causes a lowering of the corrosion‐resistance of the steel in the welded region. This applies to some extent even with the molybdenum‐bearing steels.
Thiouracil as a supplement in rations for fattening pigs
Authors: Robinson K. L. , Coey W. E.
Published: November 2006

Experiments are described in which thiouracil was given to fattening pigs under different systems of feeding. When individually fed pigs received 0.1% thiouracil in the meal ration, they increased in weight from 150 lb. to 210 lb. almost a week sooner than the controls, with a saving of about 45 lb. meal (20%). Thiouracil given to younger pigs tended to extend the period required to increase from 100 lb. live weight to 210 lb., as compared with the controls; the saving of food was up to 75 lb. per head (17%).

From the results obtained it is concluded that the frequency of thiouracil administration, as distinct from the daily intake, is an important factor in determining the ultimate response. Attention is given to the effects of thiouracil on carcass quality and composition.
A method for the estimation of fucosterol in seaweeds
Authors: Black W. A. P. , Cornhill W. J.
Published: November 2006

A method has been worked out for the estimation of fucosterol in seaweed samples. Ether has been found to be the most satisfactory solvent for the extraction of the fats; after saponification, the fucosterol is estimated in the unsaponifiable fraction by a colorimetric method based on the Liebermann‐Burchard colour reaction.
The chemistry of mushroom composts. I.—General introduction and methods of investigation
Authors: Burrows S.
Published: November 2006

Previous analytical work on mushroom and other composts is briefly reviewed and the scope and aims of the present investigation are indicated. Methods of sampling and analysis of composts are described together with an estimate of sampling errors likely to be met with.

Acid‐insoluble ash was used as a reference constituent and absolute changes in other constituents during the processes of composting and cropping were calculated from it.
The chemistry of mushroom composts. II.—Nitrogen changes during the composting and cropping processes
Authors: Burrows S.
Published: November 2006

The absolute losses of total nitrogen from composts during their preparation from straw and activators for mushroom cultivation and during their subsequent use for mushroom cropping were determined by methods described in Part I of this series. During composting, losses depended upon the amount of nitrogen originally present, upon the temperatures attained during composting and upon the readiness with which the nitrogen activators added were converted to ammonia.

Losses of nitrogen during the cropping period were much larger than could be accounted for by its removal in the crop and it is concluded that bacterial denitrification to molecular nitrogen occurs.
The analytical determination of mineral oil in bread and buns: The effect of varying composition of these baked goods on mineral oil absorption
Authors: Cookson M. A. , Coppock J. B. M.
Published: November 2006

A method is described for the determination of mineral oil in commercial bread, which might contain added gluten and/or fat, malt breads and buns. The variation in composition of these products influences the relative quantities of mineral oil absorbed by each, and also the quantities capable of solvent‐extraction under the standard conditions described. Complete extraction of mineral oil from such products is difficult to achieve, but the ratio of mineral oil to the natural oils present in the extract obtained by solvent extraction under standard conditions is constant. Analytical results obtained with various types of bread and buns adulterated with known quantities of mineral oil permit correlation with the quantity of such oil extracted from unknown samples by the described method. This procedure is reasonably satisfactory for all the above products except malt breads. The work described in this paper has been carried out to guide the producers of baked goods in ascertaining that their products comply with the limit of 0.2% mineral oil resulting from the use of mineral oils as machinery lubricants etc. and permitted by the Mineral Oil in Food Order (1949). The variations in composition of different types of baked products and the fundamental effect these have on the quantity of mineral oil extracted under the conditions described emphasizes the difficulty confronting the public analyst in the legal interpretation of the Order. Other methods of analysis are also discussed.
The influence of soya flour on bread doughs. I.—A papain‐inhibiting factor in soya beans
Authors: Learmonth E. Mitchell
Published: November 2006

Aqueous extracts of raw soya beans are shown to inhibit the action of papain on a gelatin substrate. The strength of the inhibiting effect is compared with that of peroxide. Heating the extract weakens the inhibitor.