bluuebunny/crossref_metadata_2025_split huggingface dataset:
Odour thresholds and similarity ratings of some potato chip components
Authors: Guadagni D. G. , Buttery R. G. , Turnbaugh Jean G. 
Published: November 2006

AbstractOdour 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

AbstractAn 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

AbstractCarbarsone 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damage.Tissue arsenic residues at 24 weeks were higher with a “zero withdrawal” period than when the Carbarsone was withdrawn 4 days before slaughter, but were still of a low order: the highest individual arsenic residue was 0.4 part/million in a sample of breast muscle from a poult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.
Chemical changes occurring during the processing of sun‐dried apricot juice
Authors: Salem Sayed A. , Hegazi Sayed M. 
Published: November 2006

AbstractDuring 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

AbstractThe 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

AbstractQualitative 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

AbstractMethods 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

AbstractThe 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

AbstractA 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

AbstractA 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

AbstractThe 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

AbstractFive 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

AbstractThe 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

AbstractTwo 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

AbstractTwo 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

AbstractThe 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

AbstractThe 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

AbstractA 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

AbstractAn 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

AbstractA 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

AbstractThe 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

AbstractNitrogen 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

AbstractA 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

AbstractThe 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

AbstractThe 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

AbstractThe 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

AbstractThe 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.