bluuebunny/crossref_metadata_2025 huggingface dataset:
Genotypic and environmental variation in the total phenol and flavanol contents of barley grain
Authors: Griffiths D. Wynne , Welch Robert W.
Published: October 2006

Flavanol and total phenol contents have been determined in samples of barley grown in Britain under a wide range of environmental conditions. An assessment has also been made of the genetic variation in flavanol and total phenol contents among exotic genotypes and current UK varieties. Total phenol content decreased in the first 3 months immediately after harvest but no indication was observed that prolonged storage significantly reduced the levels of flavanols and, after the initial decline, no systematic decreases were found in total phenol content. Significant differences were found between trial sites for both constituents but these could not be related to geographical locations. An examination of inter‐varietal variation revealed significant differences among both the current UK varieties (flavanols 0.11–0.17%, total phenols 0.43–0.53%) and 85 diverse genotypes (flavanols 0.08–0.15%, total phenols 0.37–0.54%). The levels of both constituents appeared to be independent of grain size, malting quality, oil content and protein content and no significant differences were found between either two and six‐rowed varieties or husked and naked grain types.
Quantitative studies on the cotyledonary proteins in the genus Pisum
Authors: Schroeder Hartmut E.
Published: October 2006

Forty‐five lines of peas including primitive or wild forms, field peas, and round and wrinkled garden peas, were grown under uniform conditions and the seeds examined for variation in protein characteristics likely to influence nutritional value. The characters measured were crude protein, extractable protein, globulins and albumins, the percentages of legumin, total sulphur and protein sulphur, carbon: nitrogen and nitrogen: sulphur ratios. The extractable protein was separated quantitatively into an albumin fraction (20–35%) and a globulin fraction (legumin and vicilin). Without exception lines high in albumin content were low in legumin content (correlation coefficient r= −0.757). As both the albumin fraction and legumin are rich in sulphur amino acids, this negative correlation has important implications for attempts through plant breeding to improve the nutritional quality of legume seed proteins, by increasing the sulphur amino acid content. Total sulphur was not correlated with any other protein character.
The use of enzymes to predict the digestibility of animal feeds
Authors: Dowman Mary G. , Collins Frank C.
Published: October 2006

Six techniques were investigated to find a quick, reliable laboratory method for the prediction of the in‐vivo digestibility of animal feeds. Four of these techniques comprised two digestions, one with pepsin in hydrochloric acid followed by another with cellulase. In three cases the cellulase was derived from Trichoderma viride which was used at two concentrations; in addition, at one of these concentrations a step using amyloglucosidase was introduced. In another technique cellulase derived from Aspergillus niger was tested to determine how effectively it dealt with starchy materials. The fifth technique comprised the separation of the cell walls by digestion with neutral detergent solution followed by digestion with cellulase (derived from T. viride) with an additional step using amyloglucosidase for samples containing starch. The last method was an in‐vitro technique using buffered rumen liquor followed by pepsin in hydrochloric acid. Because this technique proved to estimate digestibility more accurately than any of the simple chemical methods it provided a guide to the efficiency of the enzyme techniques. The digestible organic matter in the dry matter (DOMD) was determined in each case and correlated against the DOMD value obtained using an in‐vivo technique. Two of the methods showed as good a prediction of DOMD as the in‐vitro method using rumen liquor, and the correlation coefficients were comparable. The repeatability of the methods calculated as the coefficient of variation varied between 2.5 and 3.7%. For roughages containing little or no starch the shorter techniques provided an adequate evaluation of DOMD. Starches in the cereals were adequately broken down only when the additional digestion using an amyloglucosidase (Agidex) was included; this is illustrated by the correlation values obtained.
The analysis of polyunsaturated fatty acids in meat by capillary gas‐liquid chromatography
Authors: Sinclair Andrew J. , Slattery William J. , O'Dea Kerin
Published: October 2006

Polyunsaturated fatty acids (PUFA) of lean meat from domesticated and wild ruminants (cattle, sheep, goat, sambar deer and buffalo) and non‐ruminants (pig, horse and kangaroo) have been examined by capillary gas‐liquid chromatography. Ten different PUFA were found in all specimens with linoleic acid accounting for at least 50% of the total, and arachidonic and linolenic acids being the next most abundant. The total PUFA content for the ruminants ranged from 9 % in beef to 31 % in sambar deer and for the non‐ruminants from 25 % in pig to 43 % in horse. In all species the meat phospholipids (PL) were rich in PUFA (range 24–46% of PL fatty acids), whereas the triglycerides were relatively more saturated (PUFA content range 2–17%). Overall, horse and kangaroo meat had the combination of lowest fat and highest PUFA content, whilst beef and sheep had the highest fat and lowest PUFA content. These results indicate that significant reductions in total fat intake and increases in the proportion of polyunsaturated fat in the diet could be achieved without necessarily requiring a diet low in meat.
Ophidine (β‐alanyl‐L‐3‐methylhistidine, ‘balenine’) and other histidine dipeptides in pig muscles and tinned hams
Authors: Carnegie Patrick R. , Hee Kui P. , Bell Alan W.
Published: October 2006

The amounts of anserine (β‐alanyl‐L‐1‐methylhistidine), carnosine (β‐alanyl‐L‐histidine) and ophidine (β‐alanyl‐L‐3‐methylhistidine) were determined in various muscles and other tissues of pigs. The amount of the histidine dipeptides varied with age and muscle type. Ophidine accumulated in the longissimus dorsi at a rate of 25 nmol g−1 protein day−1 while the anserine concentration remained relatively constant. Thus, an estimate of the age of a pig can be obtained from the anserine: ophidine ratio in a sample of its skeletal muscle. Because the histidine dipeptides are unaffected by cooking, it is possible from an analysis of the dipeptides to monitor the type of lean pig meat used in preparing tinned hams. As the anserine:carnosine:ophidine ratio in pig meat is quite different from that in other species it is possible to distinguish between genuine and imitation hams.
Studies on the digestibility of soya bean products, cereals, cereal and plant by‐products in diets of dogs
Authors: Kendall Peter T. , Holme David W.
Published: October 2006

The apparent digestibility of 21 plant materials was evaluated in dog diets using adult beagles. In most cases the digestibility by difference method was used. Apparent crude protein (N × 6.25) digestibility coefficients for textured soya protein, extracted soya meal, full‐fat soya flours and micronised whole soya beans ranged from 0.71 to 0.87. Digestible energy (DE) contents ranged from 14.3 to 20.8 MJ kg DM−1. Samples of wholeground wheat, barley meal and flaked maize were well digested by dogs, as were samples of refined flour, vital gluten, feeding‐oat meal and wheat‐germ meal; apparent energy digestibility coefficients ranged from 0.72 to 0.96. Wheatfeed and two distillers by‐products had lower energy digestibility coefficients (0.39 to 0.59). Other materials with low apparent digestibility in dog diets (probably because of high fibre levels) were walnut meal, almond meal, dried molassed sugar beet pulp and locust bean meal. Gross energy and dry matter digestibility coefficients of below 0.52 were obtained. Data are also presented on the digestibility of samples of rapeseed meal, cassava and dried potato. When comparison was possible, DE values measured for dogs agreed closely with those for pigs for most materials.
An evaluation of enzymic and autolytic assays for cyanide in cassava (Manihot esculenta, crantz)
Authors: Cooke Rodney D. , De La Cruz Elba M.
Published: October 2006

The total cyanide contents of cassava parenchymal tissue (peeled roots), cassava cortex (peel) and cassava leaves were evaluated by autolytic and enzymic assays. Autolysis of parenchymal tissue was studied under different conditions of pH, time and temperature and addition of exogenous enzyme and antibiotic. Optimal conditions were determined to be 24 h at 37°C in acetate buffer (0.1M; pH 5.5) with 0.1 mg ml−1 chloramphenicol. Total cyanide contents similar (about 90%) to those obtained by enzymic assay could be achieved only by the use of small sample sizes: < 1 g of parenchymal tissue, < 0.3 g of cortex and < 0.1 g of leaf tissue. This caused sampling problems because of the presence of cyanide gradients in cassava tissues, which could only be resolved by tissue homogenisation prior to analysis. A study using the enzymic assay of cyanide stability in such homogenates, at different pH values and temperatures, has indicated that subsampling must be done within 15 min so as to prevent appreciable losses in the measured cyanide contents. The rate of loss of total cyanide was found to depend not only on the proportion of total cyanide which is non‐glucosidic (free), but also on the proportion of the non‐glucosidic cyanide present as cyanohydrins. The implications with regard to residual cyanide contents on cassava processing and the advantages of the enzymic assay over autolytic methods are discussed.
The effects upon digestion in sheep of the dietary inclusion of additional salivary salts
Authors: Hadjipanayiotou M. , Harrison D. G. , Armstrong D. G.
Published: October 2006

Four mature Suffolk × half bred wether sheep, fitted with rumen fistula and re‐entrant cannulae at the proximal duodenum and terminal ileum were given in sequence, a control diet (diet 1) and that diet supplemented with either 20 or 40 g saliva salt kg−1 (diets 2 and 3 respectively). The addition of 20 g salt kg−1 failed to alter significantly the rumen fermentation pattern and dilution rate. In contrast, the feeding of diet 3 resulted in a significant increase in the molar proportions of ruminal acetate, a non‐significant decrease in propionate and a significantly higher rumen dilution rate (D), which was positively correlated with the molar proportions of acetate. Ruminal NH3‐N concentration tended to increase with salt supplementation, with the greatest concentration being observed at the highest level of salt inclusion. The presence of the salts significantly reduced the degradability of the feed protein within the reticulorumen. The dietary inclusion of the salts resulted in a non‐significant increase in total amino acid N (TAA‐N) and a significant increase in the organic matter entering the small intestine.
Effect of sulphydryl and disulphide compounds on the formation and quality of thermal aggregates of soya bean 11S globulin
Authors: Yamagishi Tatsunori , Yamauchi Fumio , Shibasaki Kazuo
Published: October 2006

The precipitate (thermal aggregates) formed in the presence of sulphydryl compounds > 0.01M [β‐mercaptoethanol (ME), gutathione (reduced form) (GSH), and cysteine (oxidised form) (Cys)] consisted of a basic monomer subunit and oligomerised sub units but did not contain polymerised subunits. The content of the basic subunits in the precipitate increased with increasing concentrations of sulphydryl compounds, and on addition of 0.5M ME reached a level of 90% or more of the precipitate. The time course of the formation of the basic monomer subunit and oligomerised subunits showed that basic monomer subunits tended to be precipitated at the initial stages of heating. This was followed by the formation of oligomerised subunits. Heating an 11S globulin solution containing sulphydryl compounds accelerated the precipitation reaction. However, this did not produce a high degree of polymerisation due to sulphydryl‐disulphide interchange. A scanning electronmicroscope image of thermal aggregation induced in the absence of any sulphydryl compounds showed, however, that polymerisation has a major role in the formation of a network structure. The mechanism of oligomer and polymer formation is discussed here.
Fluorescence of fish muscle: Description and measurement of changes occurring during frozen storage
Authors: Davis Harry K.
Published: October 2006

Changes were observed in the fluorescence of skeletal muscle of many species of fish during storage in the frozen state. As intrinsic pyridine nucleotide fluorescence associated with degree of freshness, faded, two other visible fluorochromes developed. Production of the latter was favoured by minimal pre‐freezing delays, protection from air, low pH and high cold‐store temperatures. The results suggest that careful visual examination of fish muscle fluorescence, before and after thawing, could be useful in the assessment of cold storage history.
Studies on lipoxygenase from rice (Oryza sativa L.)
Authors: Sekhar B. P. S. , Reddy G. M.
Published: October 2006

Lipoxygenase activity was studied in 10 scented and two non‐scented rice varieties. Kinetic studies at different pH levels and time intervals revealed that the optimal activity was exhibited around pH 8 and at 15 min. Specific activities ranged from 40–85 units mg−1 protein and all the scented varieties had lower values that non‐scented ones.
Response of the muscles of growing pigs to dietary lysine levels
Authors: Balogun Oluwafemi O. , Fetuga Babatunde L. , Oyenuga Victor A.
Published: October 2006

Two independent experiments were conducted to investigate the response of the muscles of two classes of pigs (10 kg and 23 kg liveweight) to varying levels of total lysine in diet. The two classes were given diets of 20 and 18 % crude protein based on yellow maize and ground‐nut cake supplemented with graded levels of L‐lysine monohydrochloride. Total lysine level in the diets ranged between 0.52 and 1.42% for 10 kg pigs and 0.50 to 1.20 for the 23 kg pigs. Only bicep femoris, psoas major, longissimus dorsi and quadricep femoris were significantly (p < 0.05) influenced by total dietary lysine level. Both adductor and tricep brachii showed greater sensitivity to extreme deficiency of lysine in diet. At the end of the experimental periods, the muscles were over 100% above their initial weights at any dietary level except adductor and tricep brachii of pigs fed 0.50% total lysine in diet. While 1.02% total lysine in diet will promote optimum development of the muscles of 10–23 kg pigs, a lower amount of lysine in diet ranging between 0.7 and 0.9 % will be adequate for positive encouragement of the growth of the muscles of 23–62 kg pigs. The exponents of Huxley's allometry equation gave an estimation of the order of maturity of the ten muscles investigated in the two classes of pigs. In the 10–23 kg pigs, adductor grew fastest and gastrocnemius grew slowest relative to the total weight of the muscles. In the 23–62 kg pigs, bicep femoris grew fastest and psoas major slowest. The percentage of individual muscle gain which could be attributed to a different ‘sensitivity’ of most of the muscles to dietary lysine concentration in 10–23 kg and 23–62 kg ranged from 30 to 40% and 27 to 69% respectively. The data tend to suggest that gastrocnemius in 23–62 kg pigs was least influenced by the size of the muscles per se (R2=0.27) and was possibly the most ‘sensitive’ to dietary lysine concentration.
The nutritional value of dried skim milk in the diet of laying hens
Authors: Stevenson Mary H. , Jackson Norman
Published: October 2006

An experiment is reported in which dried skim milk was used at levels of 0, 40, 80, 120 and 160 g kg−1 of diet to replace mainly soyabean meal in the diets of two breeds of laying hens. AME and AMEn were significantly adversely affected by the two highest levels of added dried skim milk. Food conversion efficiency and bodyweight were unaffected by the added dried skim milk. Although overall food intake and egg number were not statistically significantly affected by dietary treatment there was a tendency towards a decline in both variables at the highest level of dried skim milk inclusion. The response of mean egg weight to increasing levels of dried skim milk was positively linear. Total egg weight was significantly affected by dietary treatment, the response being quadratic.
Residues of ethoxyquin in poultry tissues and eggs
Authors: Hobson‐Frohock Anthony
Published: October 2006

Tissues of broilers raised experimentally on diets containing the feed antioxidant ethoxyquin (6‐ethoxy‐2,2,4‐trimethyl‐1,2‐dihydroquinoline) contained very low levels of this compound (<0.005 mg kg−1) both raw and after roasting. Residues were higher in liver (up to 0.063 mg kg−1) and highest in what appeared to be the major deposition site, the body fat (0.215 mg kg−1). The body fat of commercial broiler samples showed much lower levels (0.015‐0.051 mg kg−1). Leg and breast muscles from laying hens after 30 weeks on the experimental diets had low ethoxyquin levels (< 0.005 mg kg−1) with a higher liver content (0.048 mg kg−1) and again the highest level in the body fat (0.238 mg kg−1). Eggs from these hens contained 0.031 mg kg−1 ethoxyquin, probably all in the yolk. Market samples of eggs from five major producers gave an average value of 0.011 mg kg−1. A rapid and considerable loss of ethoxyquin occurred in the feed troughs, the concentration dropping from 125 mg kg−1 to 90 mg kg−1 in four hours.
The fatty acid composition of Hibiscus sabdariffa seed oil
Authors: Ahmed Wahab K. Abdel , Hudson J. F. Bertram
Published: October 2006

Analysis of Hibiscus sabdariffa seed oil from different seed collections (or cultivars), representing different growing areas, showed differences in the fatty acid pattern, especially with respect to linoleic (30.1‐37.45%) and epoxyoleic (trace to 5.3%). The results showed different values from those previously reported for the cyclopropenoid fatty acid, found to be malvalic acid (0.4‐2.0%), responsible for the positive Halphen response of the oil. It is now also established that the oil contains dihydrosterculic acid (1.0‐1.6%) which has been reported previously in other species of the genus Hibiscus. The results of the rest of fatty acids showed ranges for myristic 0.2‐0.5%, palmitic 17.4‐22.6%, stearic 3.9‐5.2% and oleic acid 34.6‐39.8%.
The nutrient content of UK wheat flours between 1957 and 1980
Authors: Wenlock Robert W.
Published: October 2006

The British Government's Voluntary Flour Sampling Scheme was designed in 1957 to replace the National Flour Survey which had operated from the War years. With the cooperation of the milling industry, representative samples of wheat flours milled in the United Kingdom for human consumption were obtained by the Ministry of Agriculture, Fisheries and Food for nutritional analysis at the Laboratory of the Government Chemist. The Scheme has operated continuously since then and the results show that each type of flour has remained almost constant in nutritional composition with year‐to‐year variations 5% or less from the mean for almost all nutrients. As flour and flour‐based cereal products are consumed in large amounts, the data obtained have significant nutritional implications which are discussed in the context of the national average dietary intakes.
The effect of heating on the haemagglutinating activity and nutritional properties of bean (Phaseolus vulgaris) seeds
Authors: Grant George , More Linda J. , McKenzie Norma H. , Pusztai Arpad
Published: October 2006

The toxic lectins present in red, white and black kidney beans (Phaseolus vulgaris) are sensitive to heat treatment and the efficiency of that treatment is greatly improved by pre‐soaking of the seeds. Heating of pre‐soaked seeds at all temperatures above 75°C caused a continuous reduction in both their haemagglutinating activity and toxicity. However, the only safe method of eliminating toxicity was to heat the fully hydrated seeds to 100°C for a minimum of 10 min.
Gummosis of stone‐fruit trees and their fruits
Authors: Boothby Derek
Published: October 2006

The factors that affect gum formation in stone‐fruit trees share the common feature of stimulating ethylene production in plant tissues. It is suggested that ethylene might play an important role in gummosis. The chemical structure of the exudate gums is similar to that of certain cell‐wall polysaccharides and it is possible that gummosis is caused by excessive formation of these polysaccharides as a result of ethylene production in the tissues.
Effects of nitrogen fertilisers on the emergence of vegetable seedlings
Authors: Page E. Ronald , Cleaver Trevor J.
Published: October 2006

Depression of percentage emergence of vegetable seedlings was linearly related to the quantity of nitrogen fertiliser applied when the fertiliser was broadcast and worked into the seed bed. Placement of fertiliser at a depth of 8 cm avoided depression of emergence. The extent to which emergence was affected depended on the weather, and on the crop, some species (e.g. lettuce) being sensitive, others (e.g. red beet) being resistant to the effects of nitrogen fertilisers. A computer program was used to calculate the effects of rainfall, evaporation and soil temperatures on the concentration of nitrate in the top 5 cm of soil in a series of 45 field experiments, and this was compared with the seedling emergence records. According to the program this concentration varied widely over short periods. Red beet and radish achieved a high percentage emergence after very brief periods of low nitrate concentration. For most crops, however, transient short periods of low nitrate concentration were insufficient for satisfactory emergence, and most crops exposed to high nitrate concentrations, even if these were not continuous, suffered some reduction of emergence. Spinach was able to resist a high concentration of nitrate during the 3 days after sowing, but not at later periods. The sensitivity of crops varied, and the period of sensitivity was also different for different crops. Methods of application of nitrogen fertilisers likely to avoid depression of seedling emergence are briefly discussed.
Volatile aroma constituents of kiwifruit
Authors: Young Harry , Paterson Vivienne J. , Burns Donald J. W.
Published: October 2006

The volatile constituents of kiwifruit (Actinidia chinensis Planch.) have been investigated. The volatiles were collected and concentrated using vacuum steam distillation and freeze concentration. The concentrated distillate was analysed by gas chromatography, gas chromatography‐mass spectrometry and reaction gas chromatography. Apart from methyl benzoate, all the components identified were alkyl and alkenyl esters, alcohols, aldehydes and ketones. The most abundant component was trans hex‐2‐enal. Odour evaluation of the components at the exit port of the gas chromato‐graph indicated that ethyl butanoate, hexanal and trans hex‐2‐enal are important contributors to the aroma of kiwifruit. One other component which does not show a peak in the chromatogram and which is not yet completely characterised may have particular significance.
Interactions between the kernel N sink, grain yield and protein nutritional quality of maize
Authors: Tsai Charles Y. , Warren Herman L. , Huber Don M. , Bressan Ray A.
Published: October 2006

The isogenic opaque‐2 (o2) and its normal counterpart of maize (Zea mays L.) hybrid ‘B14 × B37’ were used as a model system and grown under different levels of nitrogen fertility to test the importance of the kernel N sink (zein accumulation) relative to kernel osmotic potential, dry matter accumulation, grain yield and protein nutritional quality. Self‐pollination and reciprocal crosses were made with seven o2 hybrids and their normal counterparts in order to determine the effect of the kernel N sink and/or vegetative characteristics on kernel dry weight accumulation. The results indicate that with a small supply of nitrogen, both normal and o2 kernels produced only small amounts of zein, and kernel weights and grain yields were comparable. As the level of nitrogen increased, zein accumulated preferentially in normal, but not in o2, and differences in kernel weight and grain yield between these two genotypes became greater. The reduction of dry matter accumulation in o2 kernels relative to normal kernels when grown under high N levels may result from the accumulation of free amino acids and their catabolic products in the kernel as a consequence of a small N sink. These osmotica contributed to a more negative osmotic potential which may favour water movement, but reduce solute movement into the kernel. Increased zein accumulation in normal kernels enhanced kernel weight and grain yield but reduced protein nutritional quality. The concentration of lysine and tryptophan as a percentage of protein decreased as the level of N fertiliser and kernel protein in the normal kernel increased. On the other hand, the o2 mutant failed to deposit additional N as zein; therefore, the concentration of these two essential amino acids remained constant regardless of N levels. However, when lysine and tryptophan were expressed on an area (kg ha−1) basis, the amino acid yields of these two genotypes were comparable.
Assessing the colour of tomato fruit during ripening
Authors: Hobson Graeme E. , Adams Peter , Dixon Timothy J.
Published: October 2006

The use of colour to separate tomatoes into groups at distinct stages of ripeness is usually a subjective procedure. In an attempt to reduce variability, tomatoes previously sorted by eye into five categories from mature green to full red were reassessed using a tristimulus colour difference meter. Various methods of presenting the samples to the machine for colour testing and of transforming the results were compared, and a formula was developed so that objective limits for each ripening stage could be calculated. In order to obtain matched samples of fruit at any particular stage of ripeness, the instrument can be programmed to reject fruit falling outside the appropriate limits. The colour components of tomatoes of several cultivars chosen subjectively to be at the same stage of ripeness (orange‐red) were shown to be related to fruit firmness.
The volatile flavour components of commercial port wines
Authors: Williams Anthony A. , Lewis Mervyn J. , May Helan V.
Published: October 2006

Gas chromatographic‐mass spectrometric examination of aroma extracts from both Ruby and Tawny port has led to the identification of 141 components, notably 2‐methoxyphenol, dihydro‐2‐(3H)‐furanone, β‐methyl‐γ‐octalactone, cis‐4‐hydroxy‐methyl‐2‐methyl‐l,3‐dioxolane, ethyl pyroglutamate and vitispirane. Odour evaluation of the components separated by gas chromatography indicates five regions as being of potential importance in port. 2‐Methoxyphenol and dihydro‐2‐(3H)‐furanone were found in two of these regions, three others being associated with esters of succinic acid. None of these components can, however, wholly explain the port‐like odour.
Assessment of the antimetabolic effects of trypsin inhibitors from cowpea (Vigna unguiculata) and other legumes on development of the bruchid beetle Callosobruchus maculatus
Authors: Gatehouse Angharad M. R. , Boulter Donald
Published: October 2006

Insect feeding trials were carried out whereby cowpea trypsin inhibitor (CPTI) was incorporated at various levels up to 10% in pelleted meals of both a susceptible variety of cowpea and another susceptible species of legume, the chickpea. The results confirmed that CPTI, prepared by affinity chromatography, is an effective antimetabolite against C. maculatus; furthermore, it is also effective when added to pelleted chickpea meals. Bioassays using soya bean trypsin inhibitor (SBTI) and lima bean trypsin inhibitor (LBTI) showed these protease inhibitors to be relatively ineffective. Methionine supplementation of meals of resistant cowpea resulted in increased adult survival from approximately 43 to 89% relative to the controls; addition of cysteine had a similar effect. Supplementation with both methionine and tryptophan, probably the next limiting amino acid in cowpea, did not increase adult survival any further. It is concluded that CPTI is an effective antimetabolite of C. maculatus and that this type of mechanism may be widespread. However, it relies upon a finely controlled balance within the host plant which has to make available sufficient nutrients for itself but insufficient to maintain predation since this example of resistance can be overcome by by‐passing the limiting sulphur amino‐acid block.
The composition of oat husk and its variation due to genetic and other factors
Authors: Welch Robert W. , Hayward Margaret V. , Jones D. Iorwerth H.
Published: October 2006

The composition of oat husk has been determined in (i) 11 diverse oat genotypes, (ii) current high‐yielding spring and winter varieties from trials in various regions of Britain, and (iii) samples obtained from two British oat mills. Husks were comprised mainly of cell wall (>83%) with about equal quantities of cellulose and hemicellulose (∼30‐35%). Lignin and ash contents were 2–10% and 3.5–9% respectively. Protein and oil contents were low (1.6–5% and 1–2.2%) and only a proportion of the protein (40–60%) and total oil (5–30%) were of apparent nutritional significance. Starch and water‐soluble carbohydrates were very low (<2% and <1%). Pepsin‐cellulase digestibility was low (7–14%) and it was negatively correlated with lignin content in the 11 genotypes. There were significant genetic differences in composition within both the 11 genotypes and the trial varieties; however, the range was small and there were significant differences due to location among the trial varieties. Husk, which was hand‐separated from oat mill samples, was generally inferior in quality to the genotypes and varieties. However, due to groat contamination, industrially separated samples from the oat mills were similar in composition to those from other sources. It is confirmed that oat husk is a poor quality feedstuff and the most significant improvement in grain quality could be made by breeding for reduced husk content.
The role of triglycerides and phospholipids in the aroma of cooked beef
Authors: Mottram D. S. , Edwards R. A.
Published: October 2006

The intramuscular triglycerides and the structural phospholipids were selectively removed from beef muscle by solvent extraction and the aroma of the residual material assessed after cooking. Removing triglycerides had little effect on the aroma of the cooked meat, but when both triglycerides and phospholipids were removed a marked difference in aroma was observed. The headspace volatiles from the different cooked meats were entrained on Tenax GC and analysed by combined gas chromatography‐mass spectrometry. The profile of headspace volatiles for the meat devoid of triglycerides was similar to that from an unextracted control and the major components were aliphatic alcohols and aldehydes. Removing phospholipids as well as triglycerides gave a markedly different volatile profile; the quantities of aliphatic aldehydes were considerably reduced and only traces of aliphatic alcohols were found, while the amounts of benzaldehyde and pyrazines were greatly increased. The latter explains some of the changes in roast aroma.
The lipid and amino acid composition of the kiwi (Apteryx australis mantelli) ratite eggs
Authors: Body Denis R. , Reid Brian
Published: October 2006

A complete lipid assay of the egg contents from the New Zealand kiwi (Apteryx australis mantelli) was carried out and compared with that of the domestic hen. The proportion of lipid to protein in the kiwi egg (1:0.5) is nearly twice as great as in the eggs of the domestic hen (1:0.9). Hen's egg lipids also have lower quantities of triacylglycerols (65 %) and higher phospholipids (29 %) as compared with those of kiwi egg lipids as 83 % and 8 % respectively. The overall fatty acid composition from the individual major lipid constituents and protein amino acid composition of the kiwi egg matched those of the domestic hen.
The effects of soil compaction, form of nitrogen fertiliser, and fertiliser placement on the availability of manganese to barley
Authors: Goldberg Steven P. , Smith Keith A. , Holmes John C.
Published: October 2006

A study was made of the effects of seedbed compaction and use of fertiliser (application rate, placement, and the choice of ammonium or nitrate forms of nitrogen) on the availability of manganese to barley in light soils in East Scotland. Generally, the uptake of manganese by the plants was increased by increasing the amount of fertiliser applied and by compaction of the seedbed, although no significant increase in extractable soil manganese was detected. The increase in uptake from wheel‐tracks (where the compression had resulted in an element of fertiliser placement), compared with nonwheeled areas, was much greater than the effect due to overall plot compaction by tractor wheels in the absence of a fertiliser placement effect. Combine‐drilling of fertiliser with the seed resulted in large increases in plant uptake of manganese in non‐wheeled areas, compared with uptake where the fertiliser had been broadcast, but had no significant effect in the wheel‐tracks where growth and uptake were generally better. In some, but not all, experiments, significant reductions in pH occurred in the soil beneath the wheel‐tracks which were very closely correlated with increases in extractable manganese. Use of ammonium sulphate as nitrogen source also reduced the pH, compared with calcium nitrate, and this, too, increased extractable manganese and greatly improved plant growth. The probable cause of enhanced manganese availability was soil acidification brought about by nitrification of ammonium fertiliser and/or by H+ ion secretion by roots to balance the uptake of ammonium and other cations. The uptake of manganese by the plant was further improved either through concentration of fertiliser in the root zone by placement, or by soil compaction which resulted in shallow sowing of seed and a closer active relationship between roots and broadcast fertiliser. Other possible factors involved were (a) a greater exudation by roots of compounds able to dissolve insoluble manganese, in compacted soil; (b) contact reduction processes; (c) stimulation of root growth, leading to more efficient uptake by the plant, where higher rates of fertiliser were used or where the fertiliser was concentrated in localised zones in the soil.
The nutritional role of S‐methyl‐L‐cysteine
Authors: Eyre Michael D. , Phillips David E. , Evans I. Marta , Thompson Alan
Published: October 2006

Using the nitrogen balance technique, the effects of S‐Methyl‐L‐cysteine on the protein quality of egg albumin, extracted microbial protein and Maris Bead bean as well as in amino acid mixtures has been evaluated. No sparing effect was observed for methionine or cystine under any of the experimental conditions investigated. Equally, with a minor exception, no serious deleterious effect appears to result from the feeding of S‐Methyl‐cysteine.
Utilisation of Egyptian rice straw in production of cellulases and microbial protein: Effect of various pretreatments on yields of protein and enzyme activity
Authors: El‐Masry Hoda G.
Published: October 2006

Rice straw was chosen as a cheap carbon source for SCP production using a locally isolated fungus identified as Trichoderma harzianum. The chemical constituents of the raw material were cellulose 43%, hemicellulose 26% and relatively low lignin, 16%. The effects of chemical and physical pretreatments on the protein production, cellulase activity and cell mass of T. harzianum have been investigated.

Pretreatment of the raw material using a combination of NaOH and high pressure steam treatment increased its microbial digestibility from 24% to 73%. Similar results were obtained by pretreatment with sodium chlorite for holocellulose formation. However, maximum yields of cell mass and protein were obtained by the first method. The organism gave 7.18 g litre−1 cell mass and 2.50 g litre−1 mycelial protein. Treatment with sodium chlorite increased cellulase activities but gave a lower fungal yield. When the NaOH was applied with high pressure steam, the organism produced 32.8% crude protein, a yield similar to that given by the same organism cultured on soluble carboxymethylcellulose.
Evaluation of Brassica species as leaf sources for extending the processing season of a leaf protein concentrate plant
Authors: Lyon Cameron K. , Knowles Paul F. , Kohler George O.
Published: October 2006

Leaf protein concentrates (LPC) were prepared in large pilot plant equipment from seven Brassica varieties grown on plots of up to 0.06 ha. Plants were harvested about a month before and after the lucerne processing season. Best yields of LPC, from leafier or forage‐type species, were up to 0.9 t ha−1. Properties were as good as or better than those of LPC from lucerne. Lucerne processing procedures were modified to maximize yields from the more succulent Brassica plants.
Improved isolation of glucobrassicin and other glucosinolates
Authors: Hanley A. Bryan , Heaney Robert K. , Fenwick G. Roger
Published: October 2006

A convenient, rapid and straightforward method for the isolation of a number of important glucosinolates is described. The techniques presented are particularly useful for the preparative scale isolation of the indole glucosinolates, glucobrassicin and neoglucobrassicin and should facilitate the extension of studies into these important naturally occurring compounds.
Trace amounts of nitrosamines in powdered milk and milk proteins
Authors: Weston Roderick J.
Published: October 2006

No nitrosamines could be detected above a level of 1 μg kg−1 in five samples of indirectly dried skim‐milk powders, 20 samples of directly‐fired skim‐milk powders and 10 samples of directly‐fired butter‐milk powders, selected at random from eight processing plants in New Zealand over a period of 8 months continuous production. The maximum level of N‐nitrosodimethylamine (NDMA) observed in samples of milk proteins (lactic casein and lactalbumin) was 0.3 μg kg−1 (in one sample) while most of a further 10 samples showed traces of NDMA at the limit of detection of 0.1 μg kg−1.
Chemical and biological evaluation of silk worm chrysalid protein
Authors: Lin Shao‐Wen , Njaa Leif R. , Eggum Bjørn O. , Shen Hsueh‐Yuan
Published: October 2006

Dried and defatted, water extracted and hydrogen peroxide treated silk worm chrysalides (SWC) were analysed for gross composition as well as for energy, fatty acids and amino acids. The amino acid analyses showed well‐balanced amino acid patterns. Water extraction and hydrogen peroxide treatment improved odour, taste and colour of the product. Tests with rats showed that raw and water extracted SWC were well utilised whereas hydrogen peroxide treated SWC showed reduced protein utilisation. It is concluded that the water extracted SWC is better suited for eventual use as a food component than the hydrogen peroxide treated SWC.
The effect of solvent extraction upon the utilisation of rapeseed meal protein by rats
Authors: Eyre Michael D. , Rooke John A.
Published: October 2006

Untreated and formaldehyde‐treated rapeseed meals were subjected to a two‐stage extraction with aqueous and pure acetone. The extraction process significantly reduced the glucosinolate contents of the untreated and formaldehyde‐treated rapeseed meals on a proportional basis by approximately 0.85 and 0.75 respectively. The effect of both solvent extraction and formaldehyde‐treatment upon the utilisation of the rapeseed meal protein was determined using a rat bioassay. Formaldehyde‐treatment did not affect either the true digestibility or biological value of the rapeseed meal protein. However, solvent extraction whilst not affecting true digestibility increased the biological value of both untreated and formaldehyde‐treated rapeseed meals significantly by nearly 20%.
Digestive lipolysis in the preruminant calf. The abomasal hydrolysis of butter oil, coconut oil, palm oil and tallow
Authors: Edwards‐Webb John D.
Published: October 2006

The effect of intramolecular short‐chain fatty acids on the abomasal hydrolysis of long chain acyl ester bonds has been examined using four different fats. An evaluation of abomasal infusion of feeds as a technique to avoid hydrolysis of fat by salivary lipase has been made. Only calves considered to be typically functional preruminants were used for the investigations. Five preruminant calves each received five experimental milk feeds consisting of skim milk plus 3% of either butter oil, coconut oil, palm oil or tallow. All feeds were given by mouth but the feed that contained butter oil was also introduced directly into the abomasum via a simple cannula. In all cases, digesta leaving the abomasum were continuously sampled for 12 h via a re‐entrant cannula in the proximal duodenum, anterior to the entry of the bile and pancreatic ducts. Butter oil given by mouth was hydrolysed to a greater extent than the other fats. This was due not only to the ease of liberation of the short chain fatty acids, but also to an enhanced liberation of longer chain acids when short chain acids are present in the triglyceride. Butter oil introduced directly into the abomasum of truly preruminant calves was not hydrolysed, suggesting that by using this technique studies could be made in vivo of the hydrolysis of fat by pancreatic lipase alone.
Changes in carbohydrates of germinating fenugreek seeds (Trigonella foenum graecum L.)
Authors: El‐Mahdy A. Rafik , El‐Sebaiy Laila A.
Published: October 2006

The effect of germination at 25 °C for 96 h in the dark on the carbohydrates of fenugreek seed was investigated. Reducing, total reducing, non‐reducing sugar, and pentosan contents increased. Polysaccharides estimated as starch decreased. Fenugreek contained mucilage (18%), which decreased considerably during germination. The decline in mucilage content was accompanied by a drop in galactan content. Total pectic content did not change, but there was a decline in the high methoxy pectin content, while protopectin, and the low methoxy pectate salts of calcium and magnesium increased. The 70% ethanol soluble carboydrates were chromatographically determined. Fenugreek seeds contained sucrose, raffinose, stachyose, and an unidentified sugar (I). A marked increase in sucrose content was observed after germination. Raffinose, stachyose and the unknown sugar (I) decreased, while another unknown (II) appeared. The two unknown sugars may be members of the raffinose family. Maltose and fructose appeared in measurable amounts after germination.
Rapeseed meal and egg taint: Effects of B. campestris meals, progoitrin and potassium thiocyanate on trimethylamine oxidation
Authors: Pearson Arthur W. , Greenwood Neil M. , Butler Edward J. , Fenwick G. Roger , Curl Caralyn L.
Published: October 2006

The inclusion of Candle (low glucosinolate) and Yellow Sarson (high glucosinolate) rapeseed meals in the diet of laying hens (100 g kg−1 for 14 days) depressed the oxidation of trimethylamine (TMA) by about 34% and 77% respectively and raised the mean TMA content of their eggs to 0.56 and 1.47 μg g−1. A dehulled, extracted Yellow Sarson meal had only a slight effect. A high glucosinolate B. napus meal suppressed TMA oxidation almost completely when fed for only 4 days. Differences in the tainting potential of the meals were related to their progoitrin contents. When fed alone this substance had a comparable effect on TMA oxidation which was due to the formation of goitrin in the gastrointestinal tract and its inhibition of TMA oxidase. Potassium thiocyanate (250 and 1000 mg kg−1 diet for 14 days) had no effect on TMA oxidation. It is concluded that neither the breeding of low glucosinolate cultivars of rapeseed nor treatment of the meal is likely to provide a practicable solution to the taint problem and that the elimination of the tainting defect from commercial stock by selective breeding would be more effective.
Preliminary enzymolysis studies on trace element extractability from food
Authors: Crews Helen M. , Burrell J. Alan , McWeeny David J.
Published: October 2006

A preliminary investigation into the availability to man of some trace elements in foodstuffs is reported. The amounts of soluble lead, cadmium, zinc, iron and copper after a simulated digestion procedure, were measured in cereals, meats, fish and non‐root vegetables consumed in UK. Details of the enzymolysis procedure and acid digestion method are given. The results show that the amount of soluble analyte varies widely from element to element and according to food type. When added to food the behaviour of soluble inorganic forms of the elements is often markedly different to that of the endogenous elements. The implications of some of these differences are considered.
Interacting effects of tillage method, nitrogen fertiliser and secondary drainage on winter wheat production on a calcareous clay soil
Authors: Ellis Frank B. , Graham John P. , Christian Dudley G.
Published: October 2006

The response of winter wheat to nitrogen fertiliser within the range 0–200 kg ha−1 in 40 kg increments applied either in April or in May in two consecutive seasons (1976–77 and 1977–78) was tested in a field experiment on a calcareous clay soil that was either direct‐drilled, shallow tine cultivated (5–8 cm), or mouldboard ploughed (23 cm). These cultivation methods had been used on the same plots in the four preceding seasons (1973 to 1976) in a comparison of cultivation systems. A comparison was also made with direct‐drilling on land that had been deep tine cultivated (17 cm) during the 1973–76 experiment. In the second season (1977–78) effects were examined of newly drawn mole drains, on land that had been direct‐drilled or ploughed.

In both seasons the effect of cultivation method on grain yield was small when nitrogen fertiliser was applied at 80–120 kg N ha−1. Nitrogen top dressings in April gave heavier yields than the equivalent dressings in May, partly because of dry weather after the May applications in both years. There was no interaction between method of cultivation and amount of nitrogen applied in 1976–77, but a significant interaction was detected in 1977–78 which was probably associated with less nitrogen being available in the uncultivated soil during the winter and spring. The results show that the potential yield of direct‐drilled crops may have been underestimated in some earlier comparisons of different methods of cultivation where small uniform top dressings of nitrogen were applied to each cultivation treatment. Mole drainage increased yield especially at low rates of nitrogen and after direct drilling, These results indicate that direct‐drilled and ploughed land may differ in their drainage requirements.