bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical changes occurring during the storage of black tea
Authors: Stagg Geoffrey V.
Published: November 2006

The deterioration of black tea, characterised by a loss of flavour and astringency and sometimes by the acquisition of undesirable “taints” is accompanied by lipid hydrolysis and by autoxidative reactions that cause losses of theaflavins, amino acids, sugars, photosynthetic pigments and some volatile aliphatic constituents and increases in non‐dialysable pigments and some volatile phenolic components. These reactions are accelerated by moisture and heat. Although lipid oxidation is insignificant except under hot dry conditions, it is postulated that oxidation of free fatty acids released during storage occurs during brewing, and has a profound influence on the quality of the liquor.
Some factors affecting sensory thresholds and relative bitterness of limonin and naringin
Authors: Guadagni Dante G. , Maier Vincent P. , Turnbaugh Jean H.
Published: November 2006

Equivalent sweetness to varying levels of sucrose was determined for naringin dihydrochalcone (ND), neohesperidin dihydrochalcone (NHD), hesperetin dihydrochalcone glucoside (HDG) and aspartylphenylalanine methyl ester (AP). The effect of sucrose and these compounds at equivalent sweetness levels on thresholds of limonin and naringin was determined. HDG was the most effective compound and sucrose the least effective in raising the threshold or suppressing bitterness of both limonin and naringin. At 1% sucrose equivalence, limonin thresholds were increased 0,40, 150 and 220% for sucrose, NHD, AP and HDG, respectively. At 5% sucrose equivalence, naringin thresholds were increased 80, 90, 145 and 180% by AP, sucrose, NHD and HDG, respectively.
Identification of anthocyanins and distribution of flavonoids in tamarillo fruit (Cyphomandra betaceae (Cav.) Sendt.)
Authors: Wrolstad Ronald E. , Heatherbell David A.
Published: November 2006

The major tamarillo (Cyphomandra betaceae) anthocyanin pigments were isolated and identified as pelargonidin‐3‐rutinoside, pelargonidin‐3‐glucoside, cyanidin‐3‐rutinoside, cyanidin‐3‐glucoside, delphinidin‐3‐rutinoside and delphinidin‐3‐glucoside. The intense purple‐coloured jelly surrounding the seeds contained the greatest concentration of anthocyanins, delphinidin‐3‐rutinoside being the major pigment. Flavones, flavonols and leucoanthocyanins were also present in this material. The yellow‐coloured flesh contained flavones and low concentration of anthocyanins. The major anthocyanin of the skins is cyanidin‐3‐rutinoside; flavones and leucoanthocyanins are also present. It is suggested that the presence of leucoanthocyanins in pigment extracts induced degradation of anthocyanins during isolation and purification.
Chemical studies of some plant wastes from Ghana
Authors: Ankrah E. K.
Published: November 2006

The proximate composition of sodium, potassium, calcium, phosphorus and iron levels of the peels and trunk from banana and plantain plants and cocoa husk are reported. The samples were all characterised by high moisture content ranging from 78 g/100 g ripe plantain peel to 94 g/100 g for fresh plantain trunk. The peels and trunk of plantain and banana plants were poor sources of phosphorus and sodium but rich in iron and potassium. Plantain trunk contained 5 g of potassium per 100 g of dry sample. Because of their high potassium content the peels of banana fruit and the trunk of banana and plantain plants are recommended as additional raw materials for indigenous soap making in Ghana.
Effects of temperature and chlorpropham on the storage of the yam
Authors: Olorunda A. O. , McKelvie A. D. , Macklon A. E. S.
Published: November 2006

Tubers of the yam, Dioscorea alata L., were stored for 18 weeks at 10, 15, 20 and 25 ºC with isopropyl N‐(3‐chlorophenyl) carbamate (CIPC or chlorpropham) at rates of 0, 0.45 and 0.90 g/kg. At 10 and 15 ºC sprouting was suppressed even in the absence of CIPC. The chemical did not suppress sprouting at 20 ºC, but at 25 ºC it prevented further sprouting of desprouted tubers. At 10 ºC the yams soon deteriorated as a result of chilling injury. The effects of storage at chilling temperatures on subsequent salt retention capacity of yam disks confirmed that membrane damage occurred. The findings suggest that CIPC does not significantly extend the storage life of yams. Cool storage alone is more effective.
The effect of pig slurry applied to a soil surface on the composition of the soil atmosphere
Authors: Stevens Robert J. , Cornforth Ian S.
Published: November 2006

Intensive livestock production and labour‐saving methods of husbandry require the storage and subsequent disposal of large volumes of slurry on land. The effect of pig slurry, applied to a soil surface, on the composition of the soil atmosphere was investigated using laboratory soil columns. When the effect of slurry was compared with equivalent amounts of glucose, results showed that while both energy sources increased microbial activity, slurry also sealed soil pores, slowing gaseous diffusion rates and delaying the return of the composition of the soil atmosphere to that approaching air. Repeated slurry applications completely sealed the soil surface and oxygen in the soil atmosphere was rapidly depleted. Ethylene, capable of harmfully affecting root‐growth, was produced in the anaerobic soil. The fine solids fraction (less than 250 μm particle diameter) of slurry was most effective at blocking soil pores to gaseous diffusion.
Volatiles in home‐brewed beers and wines
Authors: Greenshields R. N.
Published: November 2006

Home‐brewed beers and wines from various sources have been analysed by gas‐liquid chromatography. It was found that the amount of volatiles present especially the fusel oil fraction was invariably higher than in commercially brewed drinks. The consequences and possible dangers of this are discussed.
Chlorophyll degradation products in leaf protein preparations
Authors: Holden Margaret
Published: November 2006

Following the report of photosensitisation of albino rats when fed lucerne leaf protein (LP) and the suggestion that this was due to pheophorbide, the amounts of chlorophyll‐degradation products in LPs from a range of species were determined. The results were correlated with the chlorophyllase activity of the leaves from which the preparations were made.
Starch estimation in leaf tissue—A comparison of results using six methods
Authors: Macrae J. C. , Smith Dale , McCready R. M.
Published: November 2006

Six methods for estimating starch were applied to three samples of lucerne leaflet tissue. Three of the methods, each incorporating the specific glucose‐oxidase procedure to estimate the starch hydrolysis products, gave values in close agreement with each other. These values were lower than those obtained using three other methods which employed only a non‐specific hydrolysate measurement.

Further investigation indicated that the elevated values probably were caused by inclusion of non‐starch polysaccharide in the estimation. It is suggested that the specific oxidase procedure could be easily incorporated into one of the methods which gave elevated values.
The fate of potassium bromate when used as a breadmaking improver
Authors: Thewlis Basil H.
Published: November 2006

Bread was made by bulk fermentation and also by mechanical development, from doughs containing amounts of added potassium bromate ranging from 0 to 200 parts/million and the amount of residual potassium bromate in each loaf was determined. The doughs were made from bleached and also from unbleached flours. When the added potassium bromate level was less than 50 parts/million the residual level was too small to be detected. At higher levels of addition, increasing amounts of residual potassium bromate began to appear, bulk fermentation giving more than mechanical development. Possible reasons for this behaviour are discussed.
Effect of crop maturity on leaf lipids
Authors: Hudson B. J. F. , Karis I. G.
Published: November 2006

Studies extending throughout a period of 100 days' growth have been made on the total lipids of ryegrass, kale and fodder radish. Expressed in terms of % dry matter, lipids are at a maximum of about 10 to 11% during the period of vegetative growth. Lipid yields in absolute terms are maximal at 200–300 kg/ha after 56 to 70 days from sowing, at which stage lipids have fallen to 7 to 9% of total dry matter, according to species.

Considering the fatty acids as a whole, dominant components are linolenic and palmitic, the latter rising and the former falling as maturation progresses. Minor fatty acids show no clear trend. More specific changes in fatty acid profiles are revealed when individual lipid classes are studied separately.

Lipid classes display a predictable change in pattern as maturation progresses. New growth is rich in partial glycerides and free sterols, and particularly in mono‐ and digalactosyl diglycerides and sulphoquinovosyl diglyceride. Leaves from mature or senescing crops show progressive falls in these components, accompanied by the appearance of triglycerides, free fatty acids and steryl glycosides. In the case of fodder radish the accumulation of the hydrocarbon, n‐nonacosane, is a noteworthy feature. The principal phospholipids do not change appreciably with maturation.

The trends observed on maturation show common general patterns for all the leafy crops so far studied. They do emphasise, however, the crucial importance of specifying both species and duration of growth when quoting data on leaf lipid compositions.
Metabolism of glucose during ripening of detached tomato fruit
Authors: Patching Colin R. , Maw George A. , Davies Jack N.
Published: November 2006

Detached tomato fruit at four stages of ripeness were injected with D‐[U‐14C]‐glucose. After 72 h the overall metabolism of the labelled glucose and the production of 14CO2 were greatest in red fruit and least in over‐ripe fruit. Labelled carbon was incorporated into the neutral, basic and acidic fractions of fruit at all stages of ripeness. Labelling of free fructose occurred; this was most marked in mature green and green/yellow fruit and declined during subsequent ripening. Incorporation of 14C into sucrose was observed, and this increased with ripening although there was a decrease in total (free and combined) fructose labelling. The results suggest that the sucrose synthesis takes place through the action of sucrose phosphate synthetase rather than sucrose synthetase.
Pre‐slaughter injection of sodium ascorbate as a method of inhibiting metmyoglobin formation in fresh beef
Authors: Hood D. Edward
Published: November 2006

Colour deterioration, measured by metmyoglobin accumulation, in four muscles, from 10 beef animals, intravenously injected pre‐slaughter with sodium ascorbate, is compared with similar muscles from 10 control animals, at 0 °C and 5 °C. Meat from sodium ascorbate treated animals has significantly better colour stability, particularly M. psoas major and M. gluteus medius at the higher storage temperature.
Structural functions of taste in the sugar series
Authors: Lindley Michael G. , Birch Gordon G.
Published: November 2006

Shallenberger's sweetness hypothesis in the sugars is tested by the selective blocking of single positions around a sugar ring with O‐methyl groups and sensory evaluation of the products. The location of Shallenberger's AH, B system in certain sugar structures by the identification of superfluous hydroxyl groups was anticipated. Additionally, the AH, B system in β‐D‐fructopyranose responsible for the intense sweetness of the sugar is located by sensory and infrared spectral evaluation of structurally analogous compounds.
Phenols in smoked cured meats. Phenolic composition of commercial liquid smoke preparations and Derived Bacon
Authors: Knowles Michael E. , Gilbert John , McWeeny David J.
Published: November 2006

The phenolic composition of two commercial liquid smoke emulsions has been determined by gas chromatography‐mass spectrometry of the free phenols and their trimethylsilyl ethers. The phenolic fraction of smoked bacons derived from the liquid smoke emulsions has been determined similarly and compared with the phenolic fraction of traditional kiln‐smoked bacon. A preliminary examination of phenol penetration in smoked bacon has been made on a sample prepared from a liquid smoke emulsion by electrostatic spraying.
Volatile flavour components of eggs
Authors: Macleod Alexander J. , Cave S. Jane
Published: November 2006

Using a modified Likens and Nickerson extraction apparatus and a gas entrainment method of concentration by low temperature—high vacuum distillation, approximately 115 volatile flavour components of the hen's egg were obtained. These were separated by gas chromatography and the majority were identified by combined gas chromatography‐mass spectrometry. The odours of some of the separated components were described.
Electrochemical determination of vitamin E in margarine, butter and palm oil
Authors: Atuma Samuel S.
Published: November 2006

A simple, rapid and reproducible method is described for the analysis of tocopherols in margarine, butter and palm oil. The method involves saponification, extraction of the unsaponifiable material and direct voltammetric determination. No separation technique is necessary. Two indicator electrodes, glassy carbon (GCE) and carbon paste (CPE), have been employed in this work, GCE in ethanol‐benzene (2:1) medium and CPE in 75% ethanol. The CPE gives over ten times as much current as the GCE for a given tocopherol concentration. The GCE' high residual current in aqueous medium makes it impractical in 75% aqueous ethanol and the CPE' solubility in benzene restricts its usage in ethanol‐benzene medium. Slight turbidity does occur sometimes when the unsaponifiable material of the samples is dissolved in 75% ethanol but this seems not to interfere in subsequent analysis. Increase in ethanol content to 90% gives a clearer solution and higher background, but no appreciable difference in the results. The results obtained by use of both electrodes are given and shown to be in close agreement with previously published results.
Volatile flavour components of parsley leaves (Petroselinum crispum (mill.) nyman)
Authors: Freeman George G. , Whenham Robert J. , Self Ron , Eagles John
Published: November 2006

Fourteen compounds have been positively identified by gas chromatography mass spectrometry and a further seven tentatively identified in the headspace vapours above minced parsley leaves and petioles under very mild extraction conditions which closely simulate those occurring during mastication. By means of enzyme inhibitors it was shown that these components were present as such in the intact leaf tissue rather than in the form of an enzyme‐non‐volatile precursor system as in Allium species and the Cruciferae. The only sulphur‐containing compound was methyl disulphide. The characteristic flavour and odour are due to the presence of monoterpene hydrocarbons.
A survey of the meat preferences of the ibos of east central state, Nigeria
Authors: Obanu Zak A.
Published: November 2006

A sample of 205 women and 95 men were interviewed to determine the preferences of the Ibos for different types of meat. Goat meat was established as the most popular and there existed a considerable appeal for game meat. The order of preference of the various meat cuts was: chest, hind leg, spine, abdomen, loin, front leg, neck, head. The principal quality attribute responsible for differences in preference or appeal was considered to be “chewability” a type of tenderness which is self‐evident but is not yet categorised or well defined in the literature. A revision of existing meat production policies and practices to reflect local preferences and conditions is recommended.
A measure of the ruggedness of the modified acid‐detergent fibre method
Authors: Collier Raymund E. , Foulds Susan M.
Published: November 2006

A ruggedness test was carried out on the modified acid‐detergent (MAD) fibre method. Three typical fodders were used for the test. Generally the MAD fibre method proved rugged.
The behaviour of the nitrification inhibitor “n‐serve” in broadcast and incorporated applications to soil
Authors: Briggs Geoffrey G.
Published: November 2006

N‐Serve rapidly evaporated from coated fertiliser crystals scattered on glass plates or on soil. In the field in May more than 80% of N‐Serve in a broadcast application volatilised overnight and no inhibition of nitrification was observed. Vapour loss from coated fertiliser incorporated 3 cm deep in soil was negligible and nitrification was inhibited for at least 9 weeks. The half‐life of N‐Serve was 28 days in a soil low in organic matter and 50 days in a soil high in organic matter. Movement of ammonium nitrogen and N‐Serve over short distances in soil was observed but leaching of N‐Serve more than 2 cm below the depth of incorporation was slight. Much N‐Serve was lost whilst coating fertiliser, particularly when using a rotary evaporator. Analysis of treated fertiliser for N‐Serve is necessary for reliable estimates of inhibitor concentration.
Isolation and identification of the volatile sulphides produced during chill‐storage of north sea cod (gadus morhua)
Authors: Herbert Rodney A. , Ellis John R. , Shewan James M.
Published: November 2006

The development of unpleasant off‐odours and flavours during the chill‐storage of trawl caught cod has been well documented1. Certain of these off‐odours have been described as sulphidy. The data reported here suggest that hydrogen sulphide methyl mercaptan and dimethyl sulphide are responsible for the sulphidy off‐odours associated with stale chill‐stored cod.
Antioxidants and pigments of Aspergillus niger
Authors: Zaika Laura L. , Smith James L.
Published: November 2006

Extracts of six fungi, four yeasts, and two species of Streptomyces were tested for antioxidant activity when added to lard. Extracts of Aspergillus niger, the microorganism that showed the strongest antioxidant activity, were subjected to adsorption and gel permeation chromatography. Two fractions that protected lard against oxidation were obtained by chromatography of A. niger extract on Sephadex LH‐20 and Bio‐Beads S‐X2. One of these fractions contained a gummy brown pigment BR, the other a bright yellow crystalline pigment Y. Pigment BR showed strong carbonyl group and methyl‐methylene group absorption in the infrared. Apparently, on the basis of spectral data, pigment Y has a linear naphthopyrone structure. Pigment BR was obtained consistently from A. niger mycelium, while pigment Y was formed sporadically. Results indicated that more than one substance in A. niger mycelium have antioxidant properties and that brown and yellow pigments apparently are associated with antioxidant activity. Synergistic effects may be important in the strong antioxidant activity of A. niger extracts.
Occurrence of volatile nitrosamines in spice premixes
Authors: Gough Terry A. , Goodhead Kenneth
Published: November 2006

Nitrosamines have been found in spice‐curing salt premixes which were used in meat products. A number of premixes were analysed using gas chromatography and high resolution mass spectrometry and the presence of N‐nitrosopiperidine was confirmed in the majority of the premixes. After storage for 6 months levels of N‐nitrosopiperidine had increased in most instances, and N‐nitrosopyrrolidine was detected in several samples.
The mineral composition of apples. Calcium concentration and bitter pit in relation to mean mass per apple
Authors: Perring Michael A. , Jackson Caroline H.
Published: November 2006

Data for bulked samples of ungraded Cox's Orange Pippin fruit obtained from many sources over a period of 18 years show that there is a general inverse relationship between mean mass per apple and mean calcium concentration. Part of the scatter around the regression curve was accounted for by differences between years but there were larger differences between samples of the same size picked from different orchards in the same year. Even with the most favourable conditions the observed samples with mean mass per apple greater than 150 g had less than 5 mg Ca/100 g when no calcium sprays were applied and in general most samples with mean masses per apple greater than 110g were likely to have concentrations of calcium below this and hence were liable to develop bitter pit. Fruit calcium level was a more important determinant of liability to bitter pit than was mean mass per apple.

Although there was some evidence of the same relationship between calcium concentration and mass when apples from the same tree were analysed individually other factors often negated it. Two‐ to three‐fold differences in calcium concentration were observed in individual apples from the same tree.
Effect of shortening during cooking on the tenderness and histology of beef
Authors: Locker Ronald H. , Daines Graeme J.
Published: November 2006

In muscles which have gone into rigor at 15°C or 37°C without shortening, prevention of cooking shortening leads to greater toughness than in samples cooked free. This tenderness difference is not seen in cold shortened muscles. A histological study showed that heat shrinkage of collagen imposes an irregular “cooking crimp” in unshortened muscle, cooked free. This is quite distinct from cold induced crimp. Cooking cold shortened muscle under restraint completely removes the cold crimp. A striking “crossed‐diagonal” orientation of the perimysial collagen in the cooked meat is described.
The formation and analysis of n‐nitrosamines
Authors: Foreman James K. , Goodhead Kenneth
Published: November 2006

The assessment of the potential carcinogenic risk to human health of the small quantities of N‐nitrosamines formed in some foodstuffs depends on the availability of information on the routes by which they can be formed and of analytical methods having adequate sensitivity and selectivity for their determination. The present state of knowledge on these two aspects is reviewed in this paper.
Formation of c‐ and s‐nitroso compounds and their further reactions
Authors: Gilbert John , Knowles Michael E. , McWeeny David J.
Published: November 2006

The possible involvement of nitrite in C‐ and S‐nitrosation reactions with either food components or food additives is reviewed. C‐nitrosation of phenols has been shown to occur in smoked bacons with the formation of trace amounts of nitrophenols, and protein‐nitrite interactions have been studied under simulated stomach conditions where three products were identified. Also some theoretically possible reactions of nitrite with the activated methylene groups of creatinine and ketones are considered. The implication of reaction with sulphydryl groups of meat proteins with loss of nitrite in meat products and of the potential formation ot S‐nitrosothiols is discussed with reference to current literature.
Analysis of nitrate and nitrite in foodstuffs: A critical review
Authors: Usher Cyril D. , Telling Geoffrey M.
Published: November 2006

A general review is presented of published methods for the determination of nitrate and nitrite levels in foodstuffs especially meat. Published methods show wide variations in techniques for extraction, clean‐up (clearing) of extracts and final determinative steps and these are critically compared. The effect of interferences due to the presence of ascorbate, sulphite and phosphate together with the formation of a “meat blank” when nitrate is reduced to nitrite with spongy cadmium are discussed. Newer techniques based on the use of ion selective electrodes and automated techniques are outlined and the application of techniques such as amperometry, liquid chromatography, ion exchange and spectrophotometry are listed.
Estimation of the monomeric phenolics of ciders
Authors: Whiting Geoffrey C. , Coggins Ronald A.
Published: November 2006

A method is described for the separation and quantitative determination of the monomeric phenolics of ciders. These are fractionally eluted from a silica‐gel column with 2‐methylpropan‐2‐ol/chloroform mixtures of increasing 2‐methylpropan‐2‐ol content. The u.v. spectrum of each fraction is obtained in the range 250‐400 nm. Fractions containing hydroxycinnamic acid esters of quinic acid are first irradiated with u.v. light to equilibrate cis and trans forms. The concentration of each of the phenolics is calculated from extinctions at appropriate wavelengths. Ciders from some cider‐apple cultivars contained in order of decreasing concentration 5‐chlorogenic acid, 4‐p‐coumarylquinic acid, catechins, phloridzin and phloretin xyloglucoside. In one cultivar catechins were undetectable while in others they exceeded the p‐coumarylquinic acid. The contribution of the phenolics to the tannin content is discussed.
A survey of volatile components of some allium species in terms of s‐alk(en)yl‐l‐cysteine sulphoxides present as flavour precursors
Authors: Freeman George G. , Whenham Robert J.
Published: November 2006

The volatile flavour components of 27 Allium species and cultivars, mostly edible but including some decorative species for comparison, have been investigated by a series of gas and thin‐layer chromatographic and u.v. spectrophotometric methods. By means of simulation experiments with synthetic precursors and intermediates, the data have been interpreted in terms of the amino acid precursors present in the intact tissues and the species classified as containing (a) S‐1‐propenyl‐, (b) S‐2‐propenyl‐ and (c) S‐methyl‐L‐cysteine sulphoxides as their principal flavour precursors. Characteristic examples of the three types are A. cepa L. (onion), A. sativum L. (garlic) and A. aflatunense B. Fedtschenko, respectively. An object of the work has been to demonstrate broad chemical similarities between species as well as their differences, which are emphasised in keys for classification on the basis of morphological characters. In addition to onion, leek, shallot, garlic and chives, species such as A. chinense, A. fistulosum and A. tuberosum have widespread use as food, particularly in the Far East. The literature on this aspect has been briefly summarised.
Effect of overwinter storage at three temperatures on the flavour intensity of dry bulb onions
Authors: Freeman George G. , Whenham Robert J.
Published: November 2006

Dry bulb onion (cv. Rijnsburger and Giant Zittau) were stored from September 1973 to late May 1974 at 2, 25°C and ambient temperature (mean 6°C). Flavour changes were monitored at intervals on freeze‐dried samples by determination of (a) pyruvate, (b) lachrymator (thiopropanal S‐oxide) and (c) g.l.c.‐headspace total peak areas. Flavour intensity increased progressively with length of storage to about 190 days and was usually followed by a steep downturn to 240 days' storage. These changes have been interpreted in terms of incidence of sprouting and changes of respiration rates.
The measurement of feruloylquinic acids and caffeoylquinic acids in coffee beans. Development of the technique and its preliminary application to green coffee beans
Authors: Clifford Michael N. , Wight John
Published: November 2006

This paper describes the development of a quantitative, colorimetric technique for the determination of feruloylquinic acids, caffeoylquinic acids and total chlorogenic acids in synthetic mixtures and green coffee beans. The results are analysed statistically and discussed with reference to previously published data.
Sweetness of sucrose and xylitol. Structural considerations
Authors: Lindley Michael G. , Birch Gordon G. , Khan Riaz
Published: November 2006

The sweetness of sucrose and xylitol is examined in relation to conformation and configuration. Arabitol, ribitol and the “galacto” and O‐methyl analogues of sucrose are also examined on a comparative basis. The Shallenberger theory of sugar sweetness, which in part relates intensity of response to the degree of intramolecular hydrogen bonding, satisfactorily explains the high sweetness of these structurally dissimilar compounds.
The source of the acyl moiety in the biosynthesis of volatile banana esters
Authors: Gilliver Peter J. , Nursten Harry E.
Published: November 2006

Using headspace analysis of incubated banana slices, it has been shown that addition of acetyl‐coenzyme A leads to marginal increases in acetic acid esters, whereas butyryl‐coenzyme A gives up to five‐fold increases in headspace concentrations of isobutyl and isopentyl butyrate. The increases in esters were much more marked, when the appropriate alcohol was added as well, those with butyryl‐coenzyme A being up to 14 times greater. Thus acyl‐coenzyme A can act as acylating agent in ester formation and, since in the absence of banana slices little change can be detected, the slices supply some essential factor.
Distribution of some volatile nitrosamines in cooked bacon
Authors: Gough Terry A. , Goodhead Kenneth , Walters Clifford L.
Published: November 2006

Bacon was fried in the normal UK domestic manner, and the rashers, the cooked‐out fat and the vapour were analysed for N‐nitrosopyrrolidine and N‐nitrosodimethylamine. Quantitative results were based on high resolution mass spectral measurements, and it was found that for both of the nitrosamines by far the greatest proportion occurred in the vapour.
Structural changes in beef muscle during ageing
Authors: Davey C. Lester , Graafhuis Arie E.
Published: November 2006

The ageing of beef muscle set in rigor mortis while restrained at twice its resting, excised length has been examined. Ageing leads to opening of gaps between the A and I bands of the sarcomere. With the shrinkage of both bands during cooking, the gaps become the major feature of the sarcomere and develop within the tenderising time‐scale. As such they represent the most distinct structural change yet encountered to explain the phenomenon of ageing. A possible reconciling of the contradictory views of ageing—splitting at the A–I junctions and decay of Z lines—is discussed.
Sulphate contents and sorption in scottish soils
Authors: Scott Norman M.
Published: November 2006

Phosphate‐extractable inorganic sulphate contents of freely drained acid surface soils representing four contrasting soil series in north‐east Scotland ranged from 13 to 60 mg S/kg soil. Of this an average of 59% was adsorbed under the conditions of extraction used. The soils were therefore well supplied with available sulphate and there are no known cases of deficiency in the area. Average group contents of adsorbed sulphate were closely related to the abilities of the soils to adsorb added sulpphate, and unlike phosphate retention, sulphate sorption seemed to depend more on active iron than aluminium.
Continuous automated assay of α‐amylase inhibitors
Authors: Vittozzi Luciano , Morisi Gino , Silano Vittorio
Published: November 2006

A Technicon AutoAnalyzer was adapted to carry out a continuous assay of α‐amylase activity to detect the presence of α‐amylase inhibitors. The manifold design is based on the same sequence as the Bernfeld reducing‐sugar procedure and allows sufficient time to detect those inhibitors which act slowly. The technique can be used to assay protein amylase inhibitors from wheat at concentrations as low as 1.7 nM. It may also be used to detect amylase activity which can continue in spite of the presence of inhibitors.
Effects of protein levels in the diets of layers on the egg production rate and the chemical composition of poultry eggs in the tropics
Authors: Babatunde Gabriel M. , Fetuga Babatunde L.
Published: November 2006

Four hundred and fifty layers of the White Leghorn and White Rock breeds were used to study the effects of graded levels of dietary proteins on the chemical composition and egg production rate of layers in the tropics. The dietary protein levels employed were 12.0, 14.0, 16.0, 18.0 and 20.0%, and the trial lasted 6 months. The results obtained showed that hen‐day production percentages increased up to the 16.0% protein diet and then declined. Feed consumed per dozen eggs also declined up to the 16% protein diet and then increased slightly. All the layers except those on the 18% protein diet lost weight to varying degrees, the birds on the 12% protein diet losing most. There were significant decreases in the percentages of eggs weighing less than 40 g and those weighing between 40 and 49.0 g, and significant increases in the percentages of eggs weighing between 50 and 59.0 g and 60 g and above, as the dietary protein levels increased. Both the total moisture and crude protein percentages were significantly increased as the dietary protein levels increased but the differences in total ash, shell and total lipid percentages were not significant and were remarkably constant.
Effect of post‐rigor muscle length on the texture of meat
Authors: Dransfield Eric , Rhodes Douglas N.
Published: November 2006

Pre‐rigor samples of beef M. sternomandibularis were allowed to pass into rigor in both lengthened and shortened states. After ageing, half of the samples from each group were stretched, the other half acting as control. The strength of the raw and heated meats was determined by a shear test. The strength of the raw meat increased in proportion to the muscle length, irrespective of when the length was altered. The strength was due mainly to the connective tissue elements. After heating, the shortened samples were tougher than the lengthened ones; stretching the muscles post‐rigor tenderised the shortened samples but not the lengthened ones. These results indicate that the texture of cooked meat was dependent on the interaction of actomyosin and connective tissue components of muscle.
Identification of volatiles from extracted commercial tuna oil with a high docosahexaenoic acid content
Authors: Crawford L. , Kretsch M. J. , Guadagni D.
Published: November 2006

Steam‐distilled volatiles from the extracted oil of cooked tuna fish were fractionated and identified by g.c.–m.s. There were 64 compounds identified in the oxygenated fraction and 62 in the hydrocarbon fraction. The hydrocarbon fraction was found to have an unusually low odour threshold of 5.0 parts/109 (in water) and 3.75 parts/109 when a solvent correction factor was applied. As expected, the odour threshold of the oxygenated fraction was much lower (0.6 parts/109 and 0.51 parts/109 when corrected).
Feeding value of silage: Silages made from freshly cut grass, wilted grass and formic acid treated wilted grass
Authors: Donaldson Elizabeth , Edwards R. Alun
Published: November 2006

Formic acid (850 g/kg) was added to wilted perennial ryegrass (dry matter = 360 g/kg) at the rate of 3.9 g/kg before ensiling. The feeding value of the resulting silage was compared with those of silages made from the wilted grass and the freshly cut grass, and with the grass itself in metabolism trials with sheep. Intakes of dry matter were depressed by fermentation, being 12.3, 9.7 and 8.5 g/kg liveweight for the acid treated, prewilted and directly ensiled material respectively. Fermentation improved the metabolisable energies which were 11.6, 12.0, 11.4 and 13.6 MJ/kg DM for the grass, and the acid treated, wilted and directly ensiled materials. In general, fermentation reduced the intake of metabolisable energy and the production potential of the material. The major factor affecting the feeding value of silage is its acceptability to the animal in terms of dry matter intake. High dry matter intakes are best achieved by limiting fermentation.
The rapid determination of trace elements in soils and plants by X‐ray fluorescence analysis
Authors: Williams Carolyn
Published: November 2006

A semiquantitative method of X‐ray fluorescence spectrometry using a manual spectrometer has been developed for the rapid determination of Mn, Fe, Ni, Cu, Zn, As, Br, Rb, Sr, Y, Zr and Pb in soils and Mn, Fe, Ni, Cu, Zn, Br, Rb and Sr in plants. An approximate analysis time for one soil is 20 min and for one plant sample is 15 min. Matrix corrections are based on the concentration of Fe2O3 and the background count rates of the sample and a standard. The results of quantitative XRFS analysis of United States Geological Survey rocks and of Standard Kale are given.
Dimethylnitrosamine levels in untreated herring meals
Authors: Hurst R. E.
Published: November 2006

An investigation has been conducted to determine the levels of dimethylnitrosamine in 13 samples of Canadian herring meals taken from the Atlantic and Pacific coasts. The concentration of dimethylnitrosamine found in these meals, which had not been treated with nitrate or nitrite varied between 0.15 and 1.0 parts/106.
Improved procedures for the isolation of pure oleic, linoleic, and linolenic acids or their methyl esters from natural sources
Authors: Gunstone Frank D. , McLaughlan John , Scrimgeour Charles M. , Watson Andrew P.
Published: November 2006

The methods normally employed for the isolation of pure methyl oleate, linoleate, and α‐linolenate from appropriate natural sources are reviewed and simple procedures for isolating these esters are recommended. Evening Primrose Oil (Oenothera biennis) is a particularly useful source of linoleic acid.
The composition of lipids from rice hulls and from the surface of rice caryopsis
Authors: Hartman Leopold , Lago Regina C. A.
Published: November 2006

Samples of hulls, of whole and ground caryopsis and of bran obtained from the Brazilian rice variety IAC 1246, were extracted with hexane and the characteristics and composition of the corresponding lipids were determined. The lipids from rice hulls showed a four times higher content of unsaponifiable matter and of free fatty acids than those from rice bran and rice caryopsis. There were also differences in the fatty acid composition as evidenced by the presence of 2–3% of saturated C22 and C24 acids and a lower proportion of unsaturated acids in the rice hull lipids. On the other hand there was a close resemblance between the rice hull lipids and those on the surface of the caryopsis. Chromatographic analysis of the unsaponifiable matter of lipids from rice hulls and caryopsis surface disclosed the presence of hydrocarbons, alcohols and sterols in ascending order, the sterols consisting of about 50% of β‐sitosterol, 20–40% of campesterol, 10–20% of stigmasterol and 2–3% of cholesterol. On the basis of the above results it was concluded that a preliminary solvent extraction of paddy rice in order to remove the waxy lipids from the hulls and the caryopsis surface would benefit the subsequent milling process and improve the quality of the brown rice and of crude rice bran oil.
Effects of shortage of calcium and other cations on 45Ca mobility, growth and nutritional disorders of tomato plants (Lycopersicon esculentum)
Authors: Chiu Tsai‐Fua , Bould Cyril
Published: November 2006

Calcium mobility in tomato plants grown in sand‐ and water‐cultures with little calcium and other cations was studied using 45Ca as a tracer. Radioautographs and 45Ca activity measurements of plant parts showed that 45Ca was “fixed” near the base (root or stem) of plants grown in low‐Ca nutrient solutions, compared with plants grown with adequate Ca in which 45Ca was readily translocated to the tops. When plants were grown with little Ca and other cations (i.e. low K, Mg and micronutrients), 45Ca was also readily translocated to the tops. Calcium stress during the fruiting stage caused serious blossom‐end rot of fruits, indicating that Ca absorbed by plants before fruiting was not readily available subsequently for fruit development. Leaf total‐Ca is not a reliable index for predicting fruit‐Ca deficiency in tomatoes.
The influence of nitrogen fertilizer on grain quality in winter wheat
Authors: Batey Thomas , Reynish David J.
Published: November 2006

Between 1966 and 1969, 44 experiments on winter wheat tested 5 rates of N applied as spring top dressings of NH4NO3. At almost every site increasing the rate of N applied, decreased grain size and increased the N content of the grain. There was a marked effect of season: the sunniest season, 1969, produced the largest grain and the lowest mean N content; the season with the least soil moisture deficit, 1968, produced the highest mean N content. There was no relationship between N content and the variety of wheat or soil type. The N content of grain grown without N fertiliser was highly significantly related to reserves of available N in the soil. i.e. to the rate of fertilizer N required for maximum grain yield, determined by experiment. By using this relationship, the fertilizer N requirement at 20 sites with nil N plots was calculated and was found to compare favourably with the ADAS N Index prediction method based largely on previous cropping. Grain density was determined on three sites in 1967; with increasing rates of N, grain density increased slightly.
Exploring the relationship between sensory data and acceptability of meat
Authors: Horsfield Stephen , Taylor L. John
Published: November 2006

A multi‐parameter scoring system for the sensory characteristics of the texture and flavour of meat or meaty products was developed. A trained panel used the system to give sensory data on 13 products. Principal Components Analysis of this data showed that the parameters of the system could be reduced to three independent components toughness, succulence and flavour, with little loss of information. The acceptability of the products (as measured by an independent panel of consumers) was shown to be predictable from the three derived components. Optimal acceptability regions in the three‐dimensional sensory space were then identified.
Lipid binding in wheat‐flour doughs: The effect of datem emulsifier
Authors: Jacobsberg F. R. , Worman S. L. , Daniels N. W. R.
Published: November 2006

Binding of lipids and added fats increased as more work was applied to wheat‐flour doughs mixed under nitrogen. Bound‐lipid levels were lower in doughs mixed in air than in those mixed in nitrogen and increase in work input had little effect on the level of bound lipid in the former. The presence of DATEM emulsifier (diacetyl tartaric esters of mono‐ and diglycerides) had little effect on the air‐mixed doughs, but brought about a considerable reduction in lipid binding in the doughs mixed under nitrogen. It is known that DATEM emulsifiers have profound effects on dough and bread properties and it is suggested that one effect of these emulsifiers is to maintain a pool of free lipid in the dough.
The electrical stimulation of beef carcasses
Authors: Bendall James R. , Ketteridge Charles C. , George Alan R.
Published: November 2006

Beef carcasses were stimulated shortly after slaughter at varying voltage, pulse frequency and duration, with the aim of accelerating the fall of pH, destruction of ATP and onset of rigor in the muscles, so that the meat could be chilled rapidly after slaughter without danger of cold‐shortening. Optimal effects were produced at 700 V, 25 Hz for 2 min, to give a total of 3000 pulses. In undressed carcasses stimulation induced a pH fall to 6.0 within 1 h of slaughter and to 5.7 within 2.5 h in the major muscles of the forelimb, back and thigh, representing a gain of more than 8 h over the time required in unstimulated carcasses hanging at 16°C. Similar results were obtained with dressed carcasses and sides, after allowing for the 50 min or so lost in dressing. The apparently high rate of pH fall from 6.3 to 5.7 after stimulation had ceased, compared with that over the same pH range in unstimulated carcasses, can be attributed mainly to the different muscle temperatures in the two cases (38 and 26°C respectively, in four major muscles). The muscles of stimulated carcasses showed no deleterious effects of stimulation. The observed drip loss from the hindlimb jointed 6 days after slaughter was not significantly greater than that from unstimulated carcasses.
Evaluation by digestibility, growth and slaughter of microbial cells as a source of protein for young pigs
Authors: Whittemore Colin T. , Moffat Ian W. , Taylor Alexander G.
Published: November 2006

Dried microbial cells were compared with white fish meal at 10 and 20% levls of inclusion in diets offered to piglets from 21–42 days of age. Digestible energy and digestible nitrogen values for diets containing dried microbial cells (DMC) or diets containing white fish meal (WFM) were 15.8 or 15.6 MJ DE/kg DM and 28.1 or 25.9g DN/kg DM at the 10% level of inclusion, and 15.6 or 15.4 MJ DE/kg DM and 35.0 or 34.3 g DN/kg DM at the 20% level of inclusion respectively. Piglets offered diets containing DMC grew at least as fast as and converted feed at least as efficiently as piglets offered diets containing WFM. At the 20% level of inclusion, gains in water, nitrogen and lipid were 4633, 170 and 435 g for diet DMC whereas equivalent values for diet WFM were 4216, 149 and 386 g; efficiencies of conversion for DE and DN were 0.27 and 0.49 for diet DMC and 0.24 and 0.44 for diet WFM.
Correlations between physicochemical and organoleptic characteristics of Lamb L. dorsi muscle
Authors: Asghar Ali , Yeates Neil T. M.
Published: November 2006

L. dorsi muscles from 23 lamb carcases were tested for a range of organoleptic, physicochemical and microstructural properties and the results subjected to statistical analysis. Tenderness was found to be directly correlated with the content of sarcoplasmic protein, myofibrillar protein, free amino nitrogen, swelling factor of stroma, and sarcomere length in pre‐rigor condition, while inversely associated with alkali‐insoluble stroma, total water, total stroma and ultimate pH value of muscle. Fibre diameter in pre‐rigor condition and lipid content showed a second‐degree polynomial relationship with tenderness. The number of cationic groups and the amounts of acid‐soluble stroma and ash were positively related to juiciness. These physicochemical characteristics, on an individual basis, accounted for 19–77% of the variation in different attributes of meat quality. This indicates a very close association between chemistry of muscle and meat quality. However, the degree and nature of the correlation between a physicochemical characteristic and an attribute of quality seem to depend considerably on the variation in other physicochemical aspects. This signifies a high degree of interdependence among the components of muscle. The “relative” effect of different physicochemical variables, independent of each other, on the parameters of quality could not be partitioned by multiple regression analysis.
The role of egg yolk lipoproteins in fatless sponge cake making
Authors: Graham Gillian E. , Kamat Virendra B.
Published: November 2006

The question of lipid release and destabilisation of egg yolk lipoproteins has been examined (a) as a function of temperature in the absence and presence of sucrose and (b) during the fatless sponge cake making. Accessibility of lipids to n‐hexane was used as a criterion of lipoprotein destabilisation. Yolk plasma is more susceptible to lipoprotein destabilisation than whole yolk at high sucrose concentrations between 70 and 100°C. During baking, yolk lipoproteins are destabilised in a random manner with over 40% of the lipids being released towards the finishing stages of cake structure development. The lipid release does not become significant until 110°C, rises sharply above 110–120°C and appears to correlate with water loss. It is predominant in regions nearer the cake periphery and in the final stages of cake structure development.