bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of nitrogen source on the synthesis of fat from sucrose by Aspergillus terreus, Aspergillus ochraceus, Cladosporium fulvum, Cladosporium herbarum and Penicillium gladioli
Authors: Singh Jagjit , Sood Madan Gopal
Published: November 2006

The influence of ammonium nitrate, ammonium sulphate, ammonium chloride, sodium nitrate, potassium nitrate and urea as nitrogen sources on the synthesis of fat by Aspergillus terreus, Aspergillus ochraceus, Cladosporium fulvum, Cladosporium herbarum and Penicillium gladioli has been studied. Sodium nitrate has proved to be the best source of nitrogen for production of fat by A. terreus, C. herbarum and C. fulvum where the highest yields obtained were of fat contents in the felt of 51.0, 29.2 and 23.5 %, respectively. In the case of A. ochraceus the highest yield of fat was obtained with urea as nitrogen source giving a fat content in the mycelium of 47.5%. The highest yield of fat by P. gladioli was obtained using ammonium nitrate, giving a fat content of 31.0%.
Changes in the ethanol‐insoluble material of tea leaves (Camellia sinensis L.) during maturation
Authors: Selvendran R. R. , Perera B. P. M. , Selvendran S.
Published: November 2006

The ethanol‐insoluble material (e.i.m.) of immature and mature tea leaves was fractionated into hot‐water‐soluble polysaccharides and proteins, ammonium oxalate‐soluble pectic acid, hemicelluloses A and B and α‐cellulose, by successive extraction with hot water, ammonium oxalate, sodium hypochlorite and cold alkali. The final residue was termed α‐cellulose. The hot‐water extract and the hot‐water‐insoluble residue were found to contain appreciable quantities of protein nitrogen. Each fraction was hydrolysed and the mixture of sugars was separated on paper chromatograms and estimated. It appeared that each stage of the extraction procedure removed from the e.i.m. a complex mixture of polysaccharides. The sugars produced on hydrolysis of the arbitrary fractions from immature and mature leaves were qualitatively similar, although there were quantitative differences and were glucose, galactose, xylose, arabinose, rhamnose, galacturonic acid and an unidentified uronic acid. Maturation was mainly accompanied by an increase in the content of lignin, hemicelluloses and α‐cellulose.
Fungal lipids. I. Effect of different nitrogen sources on the chemical composition
Authors: Bhatia I. S. , Raheja R. K. , Chahal D. S.
Published: November 2006

The effect of three nitrogen sources on the chemical composition of seven fungi, namely: Aspergillus niger, A. luchuensis, Penicillium crustosum, Alternaria tenuis, Rhizoctonia solani, Mucor sp. and Pythium irregulare has been studied. The various fungi showed a great variation with respect to lipid percentage and total lipid content. Lipid content varied from 3.2 to 41.5%. Non‐polar lipids were comprised of monoglycerides, diglycerides, free sterols, free fatty acids and triglycerides. The quantitative make‐up of the non‐polar lipid varied with different nitrogen sources. Palmitic, stearic, oleic and linoleic acids were the major fatty acids while lauric, myristic, palmitoleic, linoleic and arachidic were the minor ones. The fatty acid composition was dramatically changed by changing the nitrogen source. Since different fungi responded differently to changes in nitrogen source, no generalisation could be made.

Two‐dimensional thin‐layer chromatography of the polar lipid fraction of these fungi revealed the presence of a maximum of fifteen spots. Phosphatidyl choline, phosphatidyl ethanolamine and phosphatidyl inositol were the major spots while lysophosphatidyl choline, lysophosphatidyl ethanolamine and phosphatidyl glycerol were present in smaller quantities. In comparison to phospholipids, glycolipids (except sterol glycoside) were present in relatively lower concentration. Pythium irregulare was very characteristic in having no glycolipids at all.
Influence of dietary fish meal on egg fatty acid composition
Authors: Navarro J. G. , Saavedra J. C. , Borie F. B. , Caiozzi M. M.
Published: November 2006

Changes in the fatty acid composition of egg‐yolk fat of hens fed diets with increasing fish meal content are studied by total fatty acid analysis. The fatty acid composition of the major lipid fractions in egg‐yolk fat after feeding a high‐level fish meal diet was determined by a combination of thin layer chromatography (t.l.c.) and gas‐liquid chromatography (g.l.c.) The changes produced show a fatty acid pattern similar to those of the diets themselves. Long‐chain polyunsaturated fatty acids are deposited preferentially in the phospholipids, reaching the highest concentration in cephalin and lecithin.
Feasibility of the use of chilean nitrate as a nitrogen source for the growth of Chlorella pyrenoidosa
Authors: Rex Astrid , Romero Alejandro
Published: November 2006

Potassic Chilean nitrate, a cheap natural product of northern Chile, was found to support the growth of the unicellular green alga Chlorella pyrenoidosa, a possible sheep fodder supplement in this region. Comparisons with conventional media containing urea or KNO3 were favourable.
Studies on sulphur nutrition, flavour and allyl isothiocyanate formation in Brassica juncea (L.) coss. and czern. (brown mustard)
Authors: Freeman G. G. , Mossadeghi N.
Published: November 2006

The effect of sulphate nutrition on vegetative growth of Brassica juncea and on flavour and allyl isothiocyanate development in the seeds has been investigated using plants grown in sand culture in a glasshouse at six concentrations of sulphate in the nutrient medium. Allyl isothiocyanate was determined by the volumetric method of Raquet and the conclusions were confirmed by a semi‐quantitative gas‐chromatographic method. Mean fresh and dry weight of plant tops initially increased steeply with increase of sulphate concentration in the nutrient medium to 0.25 mequiv./l and thereafter tended to increase to an asymptotic maximum. Allyl isothiocyanate content of the seeds showed a similar response to changes in levels of sulphate nutrition. The flavour strength of the seeds also increased with increase of their sulphur content. There were highly significant correlation coefficients between total sulphur concentration in the seeds and their allyl isothiocyanate contents. Possible practical consequences of these observations in the mustard industry are briefly discussed.
Palm‐wine yeasts from parts of Nigeria
Authors: Okafor Nduka
Published: November 2006

Seventeen yeasts were isolated from samples of palm wine fermented from the sap of Elaeis sp. (9) and from the sap of Raphia sp. (8) in widely different localities in Nigeria. Twelve of the yeasts belonged to the genus Saccharomyces, four were Candida sp. and one was an Endomycopsis sp. The distribution of the yeasts did not appear to depend on the sap which was fermented or on locality. The implication of the findings with respect to palm‐wine fermentation studies is emphasised.
Effect of caffeic and p‐coumaric acids on indole‐3‐acetic acid catabolism
Authors: Tafuri F. , Businelli M. , Scarponi L.
Published: November 2006

Caffeic acid acts as an inhibitor of the indole‐3‐acetic acid (IAA)‐oxidising system and produces a large increase in the endogenous level of bound IAA extracted from Lens roots. On the contrary p‐coumaric acid acts as an activator. The conversion by phenolase of p‐coumaric acid to caffeic acid in the plant kingdom could play an important role in the in vivo regulation of IAA oxidase. IAA determination was carried out by gas chromatography (g.c.) of an ethanolic extract from the roots.
Odour thresholds and similarity ratings of some potato chip components
Authors: Guadagni D. G. , Buttery R. G. , Turnbaugh Jean G.
Published: November 2006

Odour thresholds of the major components found in steam‐volatile potato‐chip oil were determined in water and in vegetable oil. From these values and the relative percentages of the components in the extracted oil, a figure for relative odour intensity of each compound in vegetable oil was calculated. These values, together with odour similarity ratings of the compounds and fresh potato chips, indicate that 3‐methylmercaptopropanal (methional) is probably one of the most important contributors to potato‐chip aroma. Other compounds that may contribute in varying degrees include deca‐2,4‐dienal, 2‐ethyl‐3,6‐dimethyl‐pyrazine, 2‐acetyl‐1,4,5,6‐tetrahydropyridine, 2,6‐diethylpyrazine, 2‐octenal and 2‐phenylacetaldehyde.
Lead and cadmium content of some vegetable foodstuffs
Authors: Thomas B. , Roughan J. A. , Watters Evelyn D.
Published: November 2006

An analytical method and results are given for the determination of lead and cadmium in Brussels sprouts, apples, pears, cabbages, potatoes, onions, leeks, carrots, swedes, watercress, frozen vegetables, cucumber, celery, tomatoes, mushrooms and dried herbs. The lead content of the 231 samples was in the range 0.01 to 3.85 parts/million the mean being 0.05 parts/million; the range and mean of the cadmium content were 0.01 to 0.22 and 0.04 parts/million, respectively.
The effect of carbarsone (33.6% w/v p‐ureidobenzene arsonic acid) on bodyweight gain, food conversion and tissue arsenic levels of turkey poults
Authors: Worden A. N. , Wood E. C.
Published: November 2006

Carbarsone in the form of a proprietary formulation containing 33.6 w/v p‐ureidobenzene arsonic acid was fed to turkey poults at dietary levels of up to 0.075%. There was a slightly increased mortality among the birds that had received the 0.075% level from the first day after hatching, but there was no evidence of any adverse effect upon food consumption or upon bodyweight gain among the survivors up to the time of killing at 24 weeks, and no macroscopic evidence of any organ damage.

Tissue arsenic residues at 24 weeks were higher with a “zero withdrawal” period than when the Carbarsone was withdrawn 4 days before slaughter, but were still of a low order: the highest individual arsenic residue was 0.4 part/million in a sample of breast muscle from a poult that had received 0.075 part/million throughout, with a “zero withdrawal” period.
The effect of silicon on sugar cane growth in pure nutrient solution
Authors: Wong Cheong Y. You , Heitz A. , Deville J.
Published: November 2006

Si, supplied as silicic acid significantly increased cane yields of two sugarcane varieties growing in pure nutrient solution and the sucrose yield of one variety. “Leaf freckling” symptoms only developed on those plants not receiving Si.
Chemical changes occurring during the processing of sun‐dried apricot juice
Authors: Salem Sayed A. , Hegazi Sayed M.
Published: November 2006

During the production and storage of sun‐dried apricot juice, a brown colour developed. Sodium metabisulphite in different concentrations was used to inhibit the Maillard reaction which leads to this colour. Apricot dried sheets containing 1625 parts/million of sulphur dioxide were the brightest in colour and gave the highest acceptability scores. Changes which occur during the production of the sundried apricot sheets were studied. The results showed that the ascorbic acid, total carotenoids and total protein content of the apricot fruit were greatly decreased by processing as were the concentrations of phenylalanine, histidine and serine.
Phenolic compounds in frozen avocados
Authors: Ramírez‐Martínez Jose R. , Luh Bor S.
Published: November 2006

The ethyl acetate‐soluble phenolic compounds present in frozen ripe Fuerte avocados were extracted with methanol and ethyl acetate. The compounds were separated by two‐dimensional paper chromatography with n‐butanol‐acetic acid‐water (4:1:5, v/v) and 2% acetic acid solvents. Fifteen spots were found when the chromogenic reagent was FeCl 3‐K3Fe(CN)6. The individual compounds were identified by their Rf values, colour reactions, fluorescent behaviour and absorption spectra. Chlorogenic and p‐coumarylquinic acid isomers, catechins, leucoanthocyanidins, isoflavone and caffeic and p‐coumaric acids were present in the extracts of frozen avocados. Ascorbic acid‐treated frozen avocado chunks did not darken when kept under vacuum at —26°C, but turned dark if left exposed to air. Darkening of frozen chunks was associated with disappearance of most phenolic substances, except the simple cinnamic acid derivatives. Formation of new phenolic substances, especially leucoanthocyanidins and catechins, was observed during storage of the frozen chunks under vacuum.
Reaction of wheat proteins with sulphite. III. Measurement of labile and reactive disulphide bonds in gliadin and in the protein of aleurone cells
Authors: Stevens Derrick J.
Published: November 2006

Qualitative evidence for the intra‐chain character of the disulphide bonds in gliadin, has been confirmed by quantitative measurement of the total number of bonds, and of the number reacting with sulphite under differing conditions of urea concentration. The results indicated that gliadin was composed of single polypeptide chains, which contained an average of four disulphide bonds each, in labile H‐bonded configurations. Similar measurements on the protein of wheat aleurone cells, showed the presence of a high proportion of thiol groups, and a relatively low content of disulphide groups. All of the groups were accessible to reaction with sulphite, which implied that short polypeptide chains were involved in this soluble protein system. The results are discussed in relation to the development of protein in the endosperm, and in the aleurone layer, and to the rǒle of both types of protein in germination.
The aleurone layer of wheat. III. Isolation and scanning electron microscope examination of the layer and of its component parts
Authors: Stevens Derrick J.
Published: November 2006

Methods have been devised for the isolation from wheat bran of (i) large fragments of aleurone layer, (ii) contents of aleurone cells, (iii) aleurone cell walls and (iv) aleurone granules. The structure of these preparations has been examined using the scanning electron microscope. Dimensions were generally smaller than those reported by workers using conventional microscopy of wheat sections, since the latter were swollen by aqueous mounting. Although the polygonal prismatic cells varied in size and shape, an idealised cell could be described as a 35 μm cube, having walls of 2.5 μm thickness. Aleurone granules isolated from the cell contents, appeared to be spherical bodies ranging in size from 0.25 to 3.5 μm in diameter, the majority measuring about 2 μm. The granules were densely packed in a cementing matrix within the cell walls.
Volatile fatty acid production in cacao fermentation and the effect on chocolate flavour
Authors: Lopez Alexander , Quesnel Victor C.
Published: November 2006

The production of the C3 to C5 volatile fatty acids during the processing of raw cacao has been studied by means of gas chromatography. These fatty acids are produced towards the end of fermentation and also during the drying phase, if conditions are conducive to this. The time of their appearance is related to the degree of aeration of the fermenting mass. In low concentrations, they may be regarded as contributing to normal chocolate flavour, but higher concentrations, such as are associated with poor conditions of processing, cause “dull”, “insipid” off‐flavours. Suggestions are made about the mechanism of their production and the microorganisms that may be involved.
The use of titanium dioxide as a catalyst for large‐scale kjeldahl determination of the total nitrogen content of cereal grains
Authors: Williams Philip C.
Published: November 2006

A process is described for the use of titanium dioxide as a catalyst in the Kjeldahl determination of total nitrogen, in the place of the efficient, but highly toxic mercuric oxide. The titanium dioxide is incorporated into a catalyst mixture with cupric sulphate and potassium sulphate in the ratio 0.3:0.3:10.0. Using a 1.0‐g sample, the digestion process involves the use of 20 ml of concentrated sulphuric acid, 10 g of catalyst mixture, 650‐W electric heaters and a total digestion time of 35 min. The catalyst mixture is efficient, inexpensive and non‐toxic.
Determination of lignin and cellulose in forages by extraction with triethylene glycol
Authors: Edwards Colin S.
Published: November 2006

A method of lignin determination which utilises the solubility of lignin in HCl‐activated triethylene glycol at 121 °C is described. Experiments on a range of samples indicate that the method is simple, fast and reproducible, and relates well to in vitro organic matter digestibility.
Lead and cadmium content of some canned fruit and vegetables
Authors: Thomas Barry , Roughan John A. , Watters Evelyn D.
Published: November 2006

The levels of lead and cadmium have been determined in samples of canned tomatoes, blackcurrants, grapefruit, pineapples, apricots, oranges, peaches, rhubarb, apples, prunes, damsons, plums, spinach and baked beans. The lead content of the 76 samples was in the range 0.10 to 3.90 parts/million, the mean being 0.56 parts/million; the range and mean of the cadmium content were 0.01 to 0.18 and 0.02 parts/million, respectively.
Fatty acids in different pulses produced and consumed in Bangladesh
Authors: Choudhury Kamal , Rahman M. M.
Published: November 2006

Five pulse samples, Musuri (Lens esculenta), Orhor (Cajnus indicus), Motor (Pisum sativum), Kheshari (Lathyrus sativus) and Mash‐kalai (Phaseolus Munqo), produced and consumed in Bangladesh, were extracted with ether (Soxhlet). Total fat, estimated by gravimetry, ranged from 1 to 1.7 % of dry weights. Four saturated and 4 unsaturated fatty acids were detected in all in these fat extracts by g.l.c. The fat from Musuri, Orhor, Motor and Kheshari had 18 to 28 % palmitic acid and 54 to 67 % linoleic acid. Musuri fat also had oleic (17 %) and linolenic (10 %) acids as major components. Fat from Mash‐kalai had an unusual pattern of fatty acids and contained linolenic (70 %) and behenic (10 %) acids as major components. The unsaturated by saturated fatty acid ratios in the fat extracts ranged between 2.3 for Orhor to 4.4 for Musuri.
Texture changes in canned apricots. II. Study of infection with Rhizopus stolonifer under commercial conditions
Authors: Harper K. A. , Beattie B. B. , Best D. J.
Published: November 2006

The softening or “texture breakdown” found in canned apricots from the Murrumbidgee Irrigation Area of N.S.W. and thought to be caused by a pectolytic enzyme derived from Rhizopus stolonifer was not prevented by the heat treatment normally given in canning. A large experiment simulating commercial conditions without using artificial inoculation with the mould showed breakdown in some samples; a similar experiment involving long distance transport of the fresh fruit achieved significant reduction in breakdown by dipping in dichloran, an inhibitor of R. stolonifer. An experiment with fruit from the Goulburn Valley, 150 miles (240 km) south of the Murrumbidgee Irrigation Area of N.S.W., gave hardness values considerably higher than fruit from the latter area and the inoculated fruit did not show any evidence of breakdown.
The influence of processing upon the nutritive value of the potato. Studies with young chicks
Authors: D'Mello J. P. Felix , Whittemore Colin T. , Elsley Francis W. H.
Published: November 2006

Two experiments were conducted with chicks to assess the nutritive value of dried cooked potato flour and freeze‐dried raw potato. In the first experiment, chicks given a control diet containing no potato grew at a better rate than those offered 19% dried cooked potato or freeze‐dried raw potato. Chicks fed on the latter diet had marginally higher growth rates, efficiency of food conversion and nitrogen retention than those placed on the cooked potato diet. The results of a second experiment, which consisted of feeding 0, 15 and 30% dried cooked potato flour, indicated that both levels of potato depressed growth rate and efficiency of food conversion. As the diets were designed to be deficient in lysine, responses were obtained to graded concentrations of lysine at each level of addition of cooked potato. However, even at the highest level of addition of lysine (0.16%) the depression in performance caused by the addition of cooked potato was not completely reversed.
Chemical and in vivo evaluation of a brown midrib mutant of zea mays. I. Fibre, lignin and amino acid composition and digestibility for sheep
Authors: Gordon Anthony J. , Neudoerffer Thomas S.
Published: November 2006

Two types of corn (maize) were used which were genetically identical except for a mutant gene (bm1) in one which reduced the type and amount of lignin produced compared with the normal plant (Tr). The Tr plant appeared to have only slightly lower digestibilities of dry matter and fibre for sheep even though the protein contents of the cornstalks, normally less in the Tr, were equalised by supplementation with soya bean protein. Comparing the acid‐detergent method of fibre and lignin determination with an acid‐pepsin method revealed that the former method gave values considerably lower than the latter. The alkali—lignin contents of the bm1 were higher than the acid—detergent lignins which must under‐estimate the true lignin content. The acid—pepsin method gave fibre and lignin concentrations which were more closely correlated with rumen digestion of the diets as shown by dry matter loss of the diets suspended into the rumen in nylon bags. This technique also revealed there was a significant increase in the rate of rumen digestion after 69 to 74 h of incubation. Digestion of lignin on the Tr diet could be explained by loss of ferulic and p‐coumaric acids. The reduced lignin and p‐coumaric acid content of the bm corn was associated in young plants with a low phenylalanine content but normal tyrosine content suggesting that the genetic block in lignin synthesis in this plant may occur between prephenic acid and phenylalanine.
Varietal and environmental differences in the proteins of the groundnut (arachis hypogaea)
Authors: Dawson R. , McIntosh A. D.
Published: November 2006

The arachin and conarachin fractions were extracted from 8 samples of groundnut of different varieties grown in different locations. Marked variations in the electro‐phoretic patterns, especially of the conarachin fractions, were observed and the amino acid composition of the fractions showed highly significant differences. These differences appeared to be both varietal and environmental in origin.
Lipids of potato tubers. II. Lipid‐degrading enzymes in different varieties of potato tuber
Authors: Galliard T. , Matthew J. A.
Published: November 2006

The levels of two lipid‐degrading enzymes, namely a hydrolytic enzyme (lipolytic acyl hydrolase) and an oxidising enzyme (lipoxygenase) were measured in tubers from 23 varieties of potato at harvest. Twenty‐two varieties had very high levels of the hydrolytic enzyme, ranging from 5 to 50 jumol of substrate hydrolysed/ min/g of fresh weight of tuber. One variety, Desiree, contained a much lower level of this enzyme (0.06 to 0.2 units/g fresh weight). All varieties contained high levels of lipoxygenase activity in the range of 1 to 25 μmol of 02 consumed/min/g fresh weight of tuber, with linoleic acid as substrate. The combined action of these enzymes in the degradation of potato tuber lipids is discussed.
Thermal degradation of anthocyanins with particular reference to the 3‐glycosides of cyanidin. II. The anaerobic degradation of cyanidin‐3‐rutinoside at 100 °C and pH 3.0 in the presence of sodium sulphite
Authors: Adams J. B. , Woodman John S.
Published: November 2006

A mechanism is proposed for the degradation of cyanidin‐3‐rutinoside in the presence of sulphite involving the reversible formation of a 1:1 anthocyaninbisulphite complex which was shown to be stable under the conditions employed. Degradation of the anthocyanin may still take place because of the existence of the cationic and pseudobase forms of the pigment in solution at 100 °C.

Although the commercial value of sulphite as a stabiliser for the anthocyanins in canned red fruits appears to be severely limited by its effect in decolourising the pigments and increasing the rate of corrosion of the cans, a possible use for the reagent in stabilising the anthocyanins during extraction from plant tissues is suggested.
Automated determination of vitamin C in some fortified foodstuffs
Authors: Egberg David C. , Larson Paul A. , Honold Guy R.
Published: November 2006

An automated method for the determination of ascorbic acid has been applied to a variety of vitamin fortified food products. The method is based on the reduction of 2,6‐dichloroindophenol by ascorbic acid and shows a detection limit of 0.006 mg/ml with a linear absorbance relationship to 0.200 mg/ml. The method was applied to vitamin fortified cereal products, soya protein snacks and beverage concentrates over a broad range of vitamin levels. The results compared favourably with potentiometric titration for the majority of products studied. It has been shown that the automated procedure is the method of choice for the determination of ascorbic acid in the large number of food products studied.
Simple methods for routine screening and quantitative estimation of oxalate content of tropical grasses
Authors: Roughan P. Gyatten , Slack C. Roger
Published: November 2006

A thin‐layer chromatographic method is described for the semi‐quantitative detection of oxalate in tropical grasses. The method allows the processing of large numbers of samples and should be sufficiently accurate for most screening requirements. High specificity and sensitivity for oxalate is achieved with simple laboratory equipment, but strict quantitation requires the use of a gas chromatograph. It is suggested that a consideration of the oxalate content of tropical forage grasses is essential in comparisons of apparent digestibilities between species and between treatments.
Effects of season and nitrogen fertiliser upon the flavanol composition and tea making quality of fresh shoots of tea (Camellia sinensis L.) in Central Africa
Authors: Hilton P. J. , Palmer‐Jones R. , Ellis R. T.
Published: November 2006

The concentration of flavanols in fresh apical shoots of tea was highest during the cold season. Shoots plucked during slow growth conditions contained a higher proportion of simple catechins to catechin gallates, (−)‐epigallocatechin being most significantly affected. The predominant effect of nitrogen fertiliser was to depress the concentration of (−)‐epigallocatechin in the shoot. The significance of these findings with respect to tea quality is discussed.
Nitrogen balance in rats fed rices differing in protein content
Authors: Eggum Bjørn O. , Juliano Bienvenido O.
Published: November 2006

Nitrogen balance was studied in rats fed seven milled rice samples with 1.10 to 2.73% N dry basis. True digestibility (t.d.) of the protein ranged from 94.4 to 100.1%, biological value (b.v.) ranged from 67.9 to 75.2% and net protein utilisation (n.p.u.) from 64.2 to 75.3%. T.d. and n.p.u. were positively correlated with lysine content of rice protein (3.17 to 4.07 g/16 g of N). Utilisable N ranged from 0.83 to 1.81% and was mainly determined by N content of milled rice (r = 0.988**). A sample of brown rice had lower t.d. but higher b.v. than the corresponding milled rice. Digestibility of amino acids of milled rice protein by fae al analysis ranged from 94.1 to 100.0% in samples with 1.38 and 2.74% N dry basis.
Acid hydrolysis of chicken muscle protein by reflux and sealed tube methods
Authors: Otterburn Michael S. , Sinclair William J.
Published: November 2006

A comparison has been made of the acid hydrolysis of dry, defatted chicken muscle protein by open reflux and sealed tube methods. It was found necessary to agitate the sealed tube hydrolysate vigorously in order to remove all traces of peptide material and attain satisfactory hydrolysis. The difference in ease of hydrolysis between the two methods may be due to agglomeration of the protein fibrils during hydrolysis.
The nutritional evaluation of kidney beans (Phaseolus vulgaris). The effect on nutritional value of seed germination and changes in trypsin inhibitor content
Authors: Palmer Robert , McIntosh Alexander , Pusztai Arped
Published: November 2006

The total N content of kidney beans (Phaseolus vulgaris) was found to increase on germination. The overall amino acid composition however changed very little. Rats fed on a diet containing raw beans lost more weight than the protein‐free controls (negative n.p.u. value). Germination was found to bring about a gradual improvement in nutritive value probably through the elimination of some of the toxic constituents of the seed. The near doubling of the amount of trypsin inhibitors by the 8th day of germination taken together with the substantial improvement in the nutritive value of the bean appeared to rule out trypsin inhibitors as the main toxic components of raw beans.
Factors influencing the extent of biohydrogenation of linoleic acid by Rumen micro‐organisms in vitro
Authors: Harfoot C. G. , Noble R. C. , Moore J. H.
Published: November 2006

The major factors influencing the extent of biohydrogenation of linoleic acid have been investigated by a series of in vitro incubations.

Two distinct patterns of biohydrogenation were obtained; one in which biohydrogenation was complete and 18:0 was the major end‐product and one in which trans‐11 octadecenoic acid was the major end‐product.

The major factor affecting the pattern of hydrogenation was the initial concentration of 18:2 used; at concentrations less than 1.0 mg/ml of rumen contents 18:0 was the major end‐product of hydrogenation, at concentrations of 1.0 mg/ml of rumen contents or greater the major end‐product of hydrogenation was the trans‐11 monoenoic acid. That the availability of hydrogen played an important role in the extent to which 18:2 was hydrogenated was investigated by the addition of sucrose either at the start of incubation or continuously throughout the 6‐h period of incubation. Addition of sucrose throughout the incubation increased the extent of conversion of 18:2 to 18:0. Extending the duration of incubation to 10 h had no effect on the amount of 18:0 produced.

Evidence is presented to suggest that large amounts of 18:2 prevent hydrogenation of 18:1 to 18:0 by irreversible inhibition rather than by simply competing for hydrogen.
Analysis of trace elements, phosphorus and sulphur, in the lipid and the non‐lipid phase of halibut (Hippoglossus hippoglossus) and tunny (Thunnus thynnus)
Authors: Lunde Gulbrand
Published: November 2006

The following elements have been found in the lipid phase of samples of halibut (Hippoglossus hippoglossus) and tunny (Thunnus thynnus): arsenic, bromine, selenium, zinc, iron, phosphorus and sulphur, and in the non‐lipid phase: cadmium, lead, copper, selenium, zinc, iron, arsenic, mercury and sulphur.

Of the results the following should be emphasised: a surprisingly high content of sulphur was observed in the lipid phase suggesting a new group of lipids. The results indicate, furthermore, a rather constant selenium to sulphur ratio in defatted meal while the corresponding ratio in the lipid phase is more variable. No accumulation of cadmium compared with zinc seems to take place.
Conditioning studies on Australian wheat. I. The effect of conditioning on milling behaviour
Authors: Butcher J. , Stenvert N. L.
Published: November 2006

The effect of moisture level and lying time on the milling behaviour of a number of Australian wheat varieties was investigated. Significant differences were noted in the time required to reach optimum milling performance and this was also dependent on the level of water addition. Possible explanations for this behaviour include variations in the rate of penetration of added moisture and the condition of the aleurone/sub‐aleurone interface.
Conditioning studies on Australian wheat. II. Morphology of wheat and its relationship to conditioning
Authors: Moss R.
Published: November 2006

A morphological study was carried out on three hard and three soft Australian wheat varieties. A number of staining techniques were developed to reveal the structure of the bran layers and the endosperm and hence to establish any inter‐varietal differences. This information has been used to facilitate the explanation of expected differences in the rate of penetration of the water used in the conditioning of wheat prior to milling, and in the milling yields themselves. Possible explanations for these differences in behaviour include variations in the thickness and composition of the outer cuticle and testa, the extent to which the outer epidermal and inner parenchymal cells have been compressed, and the number and size of protein masses present in the sub‐aleurone endosperm cells.
A comparative study of titrimetric and gravimetric methods for the determination of organic carbon in soil
Authors: Kalembasa Stanislaw J. , Jenkinson David S.
Published: November 2006

Two gravimetric procedures for determining carbon in soil, one a dry combustion method and the other a wet oxidation method, were compared with seven variants of the titrimetric method, all based on titrimetric determination of the dichromate consumed when soil is heated with dichromate and acid. The coefficients of variation of the methods were, as percentages: dry combustion, 0.76; wet combustion, 1.1; Tinsley I, 1.3; Tinsley II, 1.8; Tinsley III, 0.8; Anne, 1.3; Mebius, 1.8; Walkley and Black, 1.6 and Tyurin, 8.5. Taking the dry combustion method as standard, the percentage recovery of organic carbon from 22 soils was 99 for wet combustion, 95 for Tinsley I, 95 for Tinsley II, 97 for Tinsley III, 93 for Anne, 95 for Mebius, 77 for Walkley and Black and 93 for the Tyurin method. A variant of the Tinsley method (Tinsley III) is proposed as a quick procedure when the accuracy of dry combustion is not essential.
Gravimetric determination of soil carbon using the LECO induction furnace
Authors: Carr Charles E.
Published: November 2006

A gravimetric method of determining soil carbon using a LECO high‐frequency induction furnace is described. The results obtained using this method were compared with those obtained using two other gravimetric procedures: a wetoxidation method and a dry‐combustion (680 °C) method which was taken as the standard. The results showed that the induction furnace method is satisfactory for the determination of soil carbon within the range covered by the 22 soils studied. The method is relatively simple and an operator can perform about 12 determinations/hour.
Spectrophotometric estimation of arsenic in nitric acid extracts of soil and soil additives
Authors: Collier Graham F.
Published: November 2006

The spectrophotometric determination of arsenic in solutions containing nitric acid necessitates the removal of nitrate ions without loss of arsenic. A convenient and effective method for its removal was achieved by treatment with formic acid.
Volatile components of baked potatoes
Authors: Buttery R. G. , Guadagni D. G. , Ling L. C.
Published: November 2006

The vacuum steam volatile components of whole baked potatoes have been analysed by the direct combination of capillary gas‐liquid chromatography and mass spectrometry. Forty‐two compounds, mostly pyrazines and aliphatic aldehydes were characterised with some certainty. Some information was obtained about the identities of an additional 12. In the authors' opinion the components most important to baked potato aroma include 2‐ethyl‐3,6‐dimethylpyrazine, 3‐methyl‐mercaptopropanal (methional), deca‐trans,trans‐2,4‐dienal and possibly 2‐ethyl‐3,5‐dimethylpyrazine. Qualitatively the pattern of components characterised is very similar to that found in potato chips (the English potato crisp). Comparison of the volatile oils obtained from the baked potato skins and the potato insides showed a considerably greater ratio of pyrazines to aldehydes in the skins indicating that the pyrazines are probably formed largely in the skins.
Fermented foods in common use in Egypt I. The nutritive value of kishk
Authors: Morcos Sabry R. , Hegazi S. M. , El‐Damhougy Soraya T.
Published: November 2006

The nutrient contents as well as the amino acid pattern of kishk samples were determined. The level of most of the amino acids were also estimated. High figures for digestibility, biological value and net protein utilisation of kishk were obtained. The use of kishk in school feeding programmes and in military canteens as a high protein food is discussed.
Large‐Scale preparation of gliadin proteins
Authors: Patey Alan L. , Evans David J.
Published: November 2006

By a combination of carboxymethylcellulose ion‐exchange chromatography and gel‐filtration α, β and γ‐gliadin proteins have been isolated in quantities large enough to be suitable for clinical feeding and baking tests. A pure ω‐gliadin has been obtained by the use of ion‐exchange chromatography alone.
Influence of genetically determined differences in glucosinolate content on the nutritional value of rapeseed meal
Authors: Josefsson Egan , Munck Lars
Published: November 2006

Rapeseed meals derived from heat‐treated seed samples representing a large variation in glucosinolate content, which was principally due to genetic differences, were fed to mice as the only protein source. A glucosinolate content corresponding to a level of more than 1 mg potential isothiocyanates and oxazolidinethiones per g of diet depressed the 11‐day growth of mice as well as feed consumption and protein efficiency ratios.
The effect of repeated freeze–thaw cycles on tenderness and cooking loss in beef
Authors: Locker Ronald H. , Daines Grahame J.
Published: November 2006

When beef neck muscle, maintained at rest length, was subjected to repeated freezing and thawing, the increases in tenderness were small and significant only when taken in aggregate after two or three cycles. Cooking losses rose steeply after freezing once. There was a very small but significant rise after further cycles. Aging did not affect cooking loss. The rate of aging in meat after freezing and thawing increased, approaching significance. There were large variations in the ability of different samples to be tenderised by freezing or by aging.
Effects of controlled atmosphere storage on respiratory metabolism of apple fruit tissue
Authors: Knee Michael
Published: November 2006

The effects of CO2 and O2 concentrations commonly used in fruit storage upon various respiratory processes in apple fruit tissue have been investigated. In manometric experiments 10% CO2 inhibited CO2 release from succinate supplied to peel discs by over 50%; CO2 release from malate was inhibited at high substrate concentrations, while CO2 release from pyruvate was not affected. High CO2 concentrations also inhibited 14CO2 release from succinate 1,4‐14C and succinate 2,3‐14C supplied to peel discs. It is concluded that succinate dehydrogenase is the respiratory enzyme most affected by CO2 concentration.

Oxygen uptake was found to be 50% inhibited at ambient concentrations of 0.5% O2 for cortical tissue and 5% O2 for peel tissue. It is concluded that cytochrome oxidase is responsible for O2 uptake in peel and cortical tissue. The apparent low affinity for O2 in peel respiration may be due to limited O2 diffusion through the tissue. It is concluded that O2 uptake by the bulk of the apple is not directly affected by O2 concentrations employed in fruit storage.
The influence of slaughter weight on the stability of pork sides in frozen storage
Authors: Bailey Colin , Cutting Charles L. , Enser Michael B. , Rhodes Douglas N.
Published: November 2006

Eight groups of six pigs were obtained, two sources of supply × meal‐fed and swill‐fed × “light” (37 to 35 kg) and “heavy” (66 to 88 kg). The pigs were slaughtered, weighed, graded, chilled, split and the sides wrapped in stockinet and polyethylene, frozen in a room at below −30 °C and stored commercially at below −20 °C.

Corresponding sides were withdrawn after four and nine months, weight losses were measured and samples cooked and submitted to a panel for appraisal of any differences in flavour. Samples of the fat of each side were also investigated chemically for extent of oxidation of the fat.

There were no significant differences in flavour attributable to weight range, with either meal‐ or swill‐feeding nor any chemical indication of oxidative rancidity.
Conversion of a weak flour to a strong one by increasing the proportion of its high molecular weight gluten protein
Authors: Macritchie F.
Published: November 2006

A weak, over‐extensible flour was modified by additions of gluten fractions which had been obtained from the same flour. The physical dough‐testing characteristics of a strong, well‐balanced flour could be closely matched by additions of a suitably proportioned mixture of the whole gluten and a high molecular weight protein fraction of the gluten, prepared by fractional extraction.
Further studies on a specific basic protein from bread wheat
Authors: Minetti Maurizio , Rab Anis Ur , Silano Vittorio , Pocchiari Francesco
Published: November 2006

This paper describes characterisation studies on a specific cathodic protein (p.c.s.) from an Italian bread wheat (var. Mentana) by using an anti‐p.c.s. specific immunoserum as a marker. The p.c.s. isoelectric point, determined by gel electrofocusing, was 9.1 which is in good agreement with the very low cathode migration (RF 0.03) exhibited by this protein in a glycine–Tris buffer (pH 8.7). P.c.s. molecular weight, determined by gel filtration on Sephadex G100, was about 18 000 daltons.

These properties as well as p.c.s. solubility properties suggest an albumin nature for this protein.

About 80% of the total p.c.s. amount in the seed can be extracted with water, whereas NaCl solutions of molarity higher than 30 mM are needed for the extraction of the remaining 20%.

Although the two fractions have different extraction properties, they are identical as far as their immunological, electrophoretic and solubility properties are concerned. These data are consistent with the presence of two p.c.s. pools in the seed. The p.c.s. that can be extracted only at higher ionic strength may be bound by salt bonds to a water‐insoluble component of the seed.

The bound p.c.s. pool appears to be concentrated in the seed outer layer, whereas the unbound p.c.s. has a heterogeneous distribution decreasing from the pericarp towards the inside of the amyloid almond.

A possible peroxidase activity of the p.c.s. is suggested by the coincidence of a peroxidase band with the p.c.s. band in the polyacrylamide gel electrophoretic patterns of water and salt extracts from whole wheat flour.
Poultry manure phytotoxicity
Authors: Minchinton I. R. , Jones D. L. , Sang J. P. L.
Published: November 2006

Examination of samples of deep litter poultry manure which caused growth deformation in vegetable crops resulted in the isolation of a potent phytotoxic compound. The chemical properties and symptoms produced by tomato plants grown under hydroponic conditions, showed that it was not 2,4‐D as suggested by other workers but a nitrogen heterocyclic compound with an attached carboxyl group.

Poultry trials have shown that an impurity, 4‐amino‐3,5‐dichloro‐2,6‐lutidine, in the coccidiostat clopidol (3,5‐dichloro‐2, 6‐dimethyl‐4‐pyridinol) causes similar phytotoxicity. Increased potency after poultry ingestion indicates that this impurity is metabolised. The most likely metabolite is 4‐amino‐3,5‐dichloro‐6‐methyl picolinic acid. Chemical and physical data of the metabolite are identical to that of the toxic compound isolated from original manure samples.

Detailed symptomology produced by the toxic manure on tomato plants is described.
Analysis of commercial soya additives in meat products
Authors: Guy R. C. E. , Jayaram R. , Willcox C. J.
Published: November 2006

The quantitative aspects of the analysis of commercial soya additives in meat products have been investigated using a polyacrylamide gel electrophoresis technique. Extraction of the proteins from the food products was carried out either in 8 M‐urea and 1%, 2‐mercaptoethanol at 18 to 20 °C for 16 h (Method 1), or 10 M‐urea and 4%, 2‐mercaptoethanol at 100 °C for 30 min (Method 2). The proteins in the extracts were separated by electrophoresis on gels containing 6% polyacrylamide and either 6 M‐urea (Method 1) or 8 M‐urea (Method 2) using a 0.06 M‐Tris‐glycine buffer, pH 8.6. Densitograms of the stained protein bands were used for the quantitative estimation of the soya proteins. Both methods were found to give quantitative results for the analysis of soya protein additives in beefburgers and sausages. Method 1 was also found to give quantitative results for meat pie fillings and canned meat loaf products, which had been autoclaved at 115 °C for 40 min.
Conditioning studies on Australian wheat. IV. Compositional variations in the bran layers of wheat and their relation to milling
Authors: Lee J. Wilson , Stenvert Nick L.
Published: November 2006

Analysis of hand dissected bran and detergent fibre from six Australian wheat cultivars has shown that the rate of water penetration into grains during conditioning for milling, may in part be explained by some aspects of chemical composition of the bran. The degree of branching in bran arabinoxylans appears to be important; the more highly branched polysaccharides providing a greater barrier to water movement. The lipids may also cause a retardation of water movement through the bran layers of the wheat grain.
Transport and toxicity of sulphur dioxide in Saccharomyces cerevisiae var ellipsoideus
Authors: Macris Basil J. , Markakis Pericles
Published: November 2006

The kinetics of radioactive SO2 uptake by S. cerevisiae var. ellipsoideus, the effect of temperature on the uptake, the irreversible thermal inactivation of the uptake and the specificity for the molecular form of SO2 in the process indicate that mediated transport is operative in this uptake. Both the transport and toxicity of SO2 in this yeast are strongly pH‐dependent and the dependence is based on the determining effect pH exerts on the distribution of the forms which SO2 assumes in solution.
The sorption of iodide by soil components
Authors: Whitehead D. C.
Published: November 2006

The sorption of iodide by several soil component materials was examined over a range of pH values and compared with sorption by a surface soil. A compost, prepared from grass roots which had been allowed to decompose for 24 weeks, sorbed substantial amounts of iodide from solution and showed changes in sorption, due to pH and drying, similar to those shown by the soil. Freshly precipitated hydrated ferric oxide also sorbed substantial amounts of iodide from solutions of pH < 5.5 but the amount decreased to zero as the pH approached 7. Sorption by freshly precipitated hydrated aluminium oxide was impossible to assess at pH < 5 owing to its solubility but at pH 5.5 to 7.5 its sorption was similar to that of ferric oxide. No sorption of iodide was detected by kaolinite, montmorillonite, chalk or limestone.

Drying markedly reduced the capacity for iodide sorption of the compost and soil and had a smaller effect on the ferric and aluminium oxides.
An investigation into the fate of sulphites added to hard sweet biscuit doughs
Authors: Thewlis Basil H. , Wade Peter
Published: November 2006

A radiotracer technique, employing [35S]sulphur, has been used to determine the fate of sulphites added to hard sweet biscuit doughs. The results show that about 93% of the sulphur added to the dough as sulphite or metabisulphite remains in the biscuit. This figure is made up of about 30% sulphur as inorganic sulphate and 63% sulphur combined in an organic form; some evidence is presented to suggest that this sulphur may be combined with the biscuit protein as S‐sulphoprotein. Less than 0.2% of the sulphur remains as inorganic sulphite in the finished biscuit.