bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydroxycinnamates of Vitis vinifera: Sensory assessment in relation to bitterness in white wines
Authors: Vèrette Eric , Noble Ann C , Somers T Chris
Published: October 2006

The bitter and astringent taste properties of hydroxycinnamoyl tartaric acids have been responsible for incorrect speculation that these compounds influence the taste of wine. The sensory contribution of the major hydroxycinnamates found in wine was evaluated by duo—trio difference tests in model wine solutions and in white wine. The major hydroxycinnamate compound, trans‐caffeoyl tartaric acid, was not detectable when added at the highest level at which it has been found in wine, 150 mg litre−1. Similarly, no significant difference in taste was produced when caffeic acid and p‐coumaric acid were added at 120 mg litre−1 and 30 mg litre−1, respectively. Trans‐2‐S‐glutathionyl caffeoyl tartaric acid, a product of oxidase activity in must, was not detectable at 50 mg litre−1. It was concluded that the hydroxycinnamates do not play any direct role in the taste of wines.
Studies of the fungicidal activity of allyl alcohol in wheat grains
Authors: Paster Nachman , Zisman Uzi , Calderon Moshe
Published: October 2006

The efficiency of allyl alcohol in controlling storage fungi in wheat grains was studied under laboratory conditions. Fumigation for 72 h with allyl alcohol at a concentration of 50 mg litre−1 totally inhibited the growth of the mycoflora naturally present in the grains. When heat‐treated grains were inoculated with spore suspensions of Aspergillus ochraceus or Aspergillus flavus, and subsequently exposed to the material, the minimal concentration needed to inhibit fungal growth (at 3 h exposure) was 15 and 25 mg litre−1, respectively. In all the above treatments the treated grains were free of moulds even after 6 months' storage at 26° C.
Flavour volatiles of Assam CTC black teas manufactured from different plucking standards and orthodox teas manufactured from different altitudes of Darjeeling
Authors: Mahanta Pradip K , Baruah Sabitri , Owuor Philip O , Murai Toshinobo
Published: October 2006

Biochemical correlations between volatile flavour constituents (VFC) of CTC bluck teas manufactured from fine and coarse plucking of Assam tea and orthodox teas fiom three different altitudes were carried out by GC‐MS. In general, fine plucking produced more monoterpenoids and less nonterpenoids than coarse plucking. The volatile flavour compounds were similar in all types of tea except that geranoic acid was detected in Darjeeling teas. The different ecosystems of Assam and Darjeeling have been found to have a pronounced impact upon aroma concentration. However, major diferences between the volatiles of teas from the different altitudes at Darjeeliny appear to be not so significant.
Glucosinolate content of Brassica vegetables‐Chinese cabbages Pe‐tsai (Brassica pekinensis) and Pak‐choi (Brassica chinensis)
Authors: Lewis Jenny , Fenwick G Roger
Published: October 2006

The glucosinolate content of 19 cultivars of pe‐tsai and three cultivars of pak‐choi Chinese cabbage (Brassica pekinensis Lour) Rupr and (Brassica chinensis L, respectively) has been determined using high performance liquid chromatography. The levels of total glucosinolates were 0.097‐0.337 g kg−1 fresh weight (mean 0.198) in pe‐tsai and 0.39‐0.704 g kg−1 (mean 0.534) in pak‐choi. The main components present were (2‐hydroxybut‐3‐enyl‐progoitrin), but‐3‐enyl‐ (gluconapin), 5‐methylsulphinylpentyl‐ (glucoalyssin) and pent‐4‐enyl (glucobrassicanapin) glucosinolates, respectively. In comparison with other UK brassicas and American cultivars of Chinese cabbage, both the UK‐grown pak‐choi and pe‐tsai are low in glucosinolates.
Studies on blood engorgement in beef carcasses
Authors: Gregory Neville G , Wilkins Lindsay J , Gregory Andrew M S
Published: October 2006

This study examined whether delayed bleeding at slaughter affected the overall appearance and residual blood content of beef. Three muscles were analysed for residual blood content, and when delayed bleeding was performed only the forequarter muscle showed high blood levels indicating that engorgement occurred where blood had gravitated within the carcass. Electrical stimulation of the carcass immediately before delayed bleeding did not expel any of the retained blood. In terms of the overall appearance of the carcass, the worst sites for blood engorgement were the thymus, lungs and subcutaneous fat at the brisket and neck. A trial was also conducted which showed that inducing a cardiac arrest helped to reduce the expression of bruises inflicted at stunning or slaughter.
Detection and origin of a novel high molecular weight glutenin subunit in hexaploid wild emmer wheat derivatives
Authors: Macgibbon D Bryan , Porter Noel G
Published: October 2006

Several hexaploid derivatives of wild emmer wheat Triticum dicoccoides L developed in Israel possessed a high molecular weight glutenin subunit having slightly lower mobility in sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE) than the Glu‐Ala subunit of the reference cultivar, Hope. The lower mobility subunit appears to have been inherited from the tetraploid wild emmer G25, a parent used in developing the derivatives. Two‐dimensional electrophoresis indicated that the lower mobility subunit from the wild emmer G25 and from the derivatives consisted mainly of two components more basic than the components of the Glu‐Ala subunit from the 20 reference cultivars examined. In 49 wild emmers examined by SDS‐PAGE, at least seven different mobilities were distinguished among the least mobile subunits. Three emmers had a subunit of comparable mobility to the G25 upper band, and one had a subunit of similar mobility to the Glu‐Ala subunit. Two‐dimensional electrophoresis confirmed the match of the former three, but demonstrated a difference between the isoelectric point of the latter and the Glu‐Ala subunit.
Factors that influence the coalescence stability of protein‐stabilised emulsions, estimated from the proportion of oil extracted by hexane
Authors: Tornberg Eva , Ediriweera Nandanie
Published: October 2006

The coalescence stability of protein‐stabilised emulsions was estimated by measuring the degree to which the oil content could be extracted by hexane. The hexane extraction method is an empirical one but it correlates well with both an absolute method, such as increase in droplet size, and with another ‘accelerating’ technique, oil separation by centrifugation. Moreover, the hexane extraction method is capable of measuring coalescence stability over a wide range of instability, whereas the centrifugation method only provides information about the final stages of emulsion instability.

Among the proteins studied, caseinates were generally the best stabilisers, especially at pH 6. Soya proteins gave rise to emulsions of minimal stability, whereas whey protein concentrate and blood plasma resulted in emulsions of medium stability.

The coalescence instability of the protein‐stabilised emulsions, viewed overall, was significantly and positively related to the droplet size, the degree of flocculation and the amount of protein in the membrane. High values of these emulsion parameters were due mainly to frequent recoalescence and bridging during emulsification. To minimise these effects emulsifying conditions creating high protein: surface area ratios should be used, as well as proteins that quickly change their conformation at an interface and have low aggregation numbers in solution.
Solar drying characteristics of papaya (Carica papaya) latex
Authors: Narinesingh Dyer , Mohammed‐Maraj Rahzia
Published: October 2006

Dripped, congealed and a mixture of dripped and congealed papaya latexes of varying charge sizes were dried in a rock‐bed solar dryer over a temperature range of 40–60°C. The time taken for the fresh latex to dry from an initial moisture content of between 73 and 80% (wet basis) to an equilibrium moisture content of between 6 and 8% varied from about 1·5 to 36 h depending upon the charge size. The latex, whether dripped or congealed, dried as pale yellow flakes which could easily be powdered and had a proteolytic activity slightly higher than that of the fresh latex.
Carotene reflectance and the yellowness of bovine adipose tissue measured with a portable fibre‐optic spectrophotometer
Authors: Swatland Howard J
Published: October 2006

The reflectance spectrum of beta‐carotene dissolved in ethanol in front of barium sulphate powder was measured with a portable fibre‐optic spectrophotometer based on a xenon flash unit and a photodiode array. Maximum absorbance (minimum reflectance) was from 470 to 490 nm. The same result was found with white adipose tissue in place of barium sulphate. Samples of subcutaneous adipose tissue from 13 cattle were measured. With a range from white to pale yellow adipose tissue, the maximum divergence of reflectance spectra was at 460 nm. With a range from pale to lemon yellow, the maximum divergence was at 410 nm. Reflectance spectra of adipose tissue had evidence of absorbance from 410 to 420 nm and at 540 and 580 nm, which might have been caused by residual oxyhaemoglobin.
Ozonated cotton stalks as a silage additive: Fermentation data on lucerne with particular reference to protein degradation
Authors: Ben‐Ghedalia Daniel , Yosef Edith
Published: October 2006

Fermentation patterns of lucerne silages were studied in laboratory silos. The treatments consisted of: (a) fresh (200 g kg>−l DM) lucerne, ensiled without any treatment (L); (b) lucerne wilted to 525 g kg−1 DM prior to ensilage (WL); (c) fresh lucerne + cotton stalks at a ratio of 60:40 on a dry matter (DM) basis (L + CS); and (d) fresh lucerne + ozone‐treated cotton stalks at the same ratio as above (L+O3). Silos were opened after 90 days and the silages analysed. The highest DM loss was found in the L silage (14·7%), whereas in the L+O3 silage DM loss was practically nil. Both wilting and the addition of untreated cotton stalks proved to be effective in reducing DM losses during fermentation. The production of lactic acid and volatile organic acids in the L+ O3 and WL silages was lower than in the L and L+CS silages. The poorest ability to preserve forage protein was found in the L silage, in which only 28 % of the protein was recovered after 90 days. The greatest ability to preserve protein was found in the L+O3 silage, in which 78 % of the protein was maintained. Ammonia production followed generally similar patterns. Amino acids underwent extensive degradation in the L silage. Recovery of amino acids in the WL silage was in the range 69–93 %, and in the L + O3 silage it was almost complete. Ozonated CS proved to be a good silage additive with respect to energy and protein preservation. Its future use in the field would allow direct ensilage of fresh leguminous material immediately after harvest, producing a high quality silage.
Fractionation of crude pentosanase (arabinoxylanase) for improvement of the nutritional value of rye diets for broiler chickens
Authors: Chickens Broiler , Grootwassink Jan W D , Campbell G Leigh , Classen Henry L
Published: October 2006

A pentosanase component of a crude enzyme product was concentrated and added to chick diets. Four levels of purity were examined: (a) the crude enzyme product, (b) a crude water extract, (c) a pentosanase purified using ion‐exchange chromatography (non‐bound fraction), and (d) residual pentosanase eluted with 0·4 M NaCl salt from the ion‐exchange column (salt‐eluted fraction). All preparations exhibited high viscosity‐reduction capabilities when tested against a soluble pentosan preparation isolated from rye grain. The absence of arabinose release during rapid viscosity reduction of pentosan indicated that the non‐bound pentosanase was an endoxylanase (1,4‐β‐D‐xylan xylanohydrolase, EC 3.2.1.8) without α‐L‐arabino‐furanosidase activity. When added to broiler chick diets containing rye as the only cereal, all enzyme preparations significantly improved growth and feed conversion. At equivalent viscosity‐reduction activity the non‐bound pentosanase was less effective than other preparations, suggesting that multiple enzymes may be necessary to elicit maximum benefit. Alternatively, since the non‐bound enzyme was less pH stable it may have lost activity in the acidic environment of the foregut.
Effect of modified atmosphere packaging on the microbial development and visible shelf life of a mayonnaise‐based vegetable salad
Authors: Buick Robert K , Damoglou Anthony P
Published: October 2006

The effect of a modified atmosphere of 20% carbon dioxide, 80% nitrogen, on the microbial development and visual shelf life of a mayonnaise‐based vegetable salad is reported. The modified atmosphere delayed the spoilage of the salad at all three chosen storage temperatures. The principal organisms causing spoilage of the salads were yeasts, those spoiling the modified atmosphere packs having a fermentative ability. Modified atmosphere packaging of the vegetable salad would allow the manufacturer to increase the shelf life of the product from 40 to 54 days at 4°C storage, 12 to 22 days at 10°C storage, and 5 to 12 days at 15°C storage.
Varietal and geographic classification of french red wines in terms of major acids
Authors: Etièvant Patrick , Schlich Pascal , Cantagrel Roger , Bertrand Main , Bouvier Jean‐Claude
Published: October 2006

Concentrations of acids other than malic and lactic appeared to be related more to area of production than to grape variety. These variables (2‐ hydroxyglutaric, butyric and isovaleric acid concentrations) were attributed to differences in the technological process used for vinification in the various areas. Shikimic and galacturonic acids were helpful for classifying and discriminating wine varieties.

Principal component analysis characterised Cabernet Franc, Grenache and Carignan wines well by their acid content but failed to discriminate Merlot from Cabernet Sauvignon and Cinsault. Stepwise discriminant analysis allowed a clear separation of all wines according to the different varieties and regions, except Cubernet Franc and Cubernet Sauvignon niade in Bordeaux. The eight groups obtained were charucterised by a selection of only nine vuriubles including 2‐hydroxyglyceric, shikimic, hexunoic and galacturonic acids, volatile acidity, and citric, decanoic, 2, 3‐dihydroxy‐2‐methylbutyric acid.

Two‐way analyses of variance applied to the Merlot and Cabernet Sauvignon wines made in Bordeaux and Narbonne demonstruted uery few or no interactions between the two factors of variation for most acids. This analysis confirmed the importance of shikimic acid for classfying wines according to the variety of the grapes and of 2‐hydroxygluturic und tarturic ucids for location.
Relationship between process of withering and aroma characteristics of black tea
Authors: Mahanta Pradip Kr , Baruah Sabitri
Published: October 2006

Volatile flavour components (VFC), caffeine, crude fibre, ash and total water soluble solids (TSS) were analysed in orthodox and CTC black teas manufactured from normal and hard withered leaves. With the increase of wither, VFC, TSS and caffeine were found to increase but not crude fibre. The withering process in black tea manufacture appears to control the development of terpenoids, improving flavour quality in brewed tea.
Effect of indigestible residue from foodstuffs on trypsin and pancreatic α‐amylase activity in vitro
Authors: Moron Dulce , Melito Carmelo , Tovar Juscelino
Published: October 2006

Indigestible residues from black beans (B; Phaseolus vulgaris L cv Tacarigua), green beans (G; Phaseolus vulgaris L), carrots (C; Daucus carota L) and rice bran (R; from Oryza saliva L) were prepared by the pepsin/pancreatin method of Hellendoorn et al and their effect on trypsin and pancreatic α‐amylase was evaluated comparing two experimental procedures. When the remaining caseinolytic enzyme activity was assayed in the soluble fraction of the fibre/trypsin mixtures, a statistically significant decrease was observed with C, R and G residues. However, assessment of trypsin activity in the presence of residues showed that C has a stronger inhibitory effect, followed in intensity by G and B. With the exception of carrot residue, the highest inhibitory effect was observed if a synthetic substrate of trypsin (BAPNA) is employed. Although all of the residues assayed inhibited α‐amylase activity on soluble starch, the effect of black bean fibre seems to be due to its tannin content. As observed for trypsin, the magnitude of α‐amylase inhibition by indigestible residue proved to be dependent on the experimental system employed. These results indicate that both experimental procedure and type of substrate have an influence on the enzyme inhibitory effect of fibre. C, R and B indigestible residues produced a slight but statistically significant decrease of in‐vitro casein digestibility index.
The oxidation of 4‐hydroxyindole as a model system for the oxidation of 4‐hydroxyindolyl‐3‐methyl glucosinolate
Authors: Truscott Roger J W , Manthey Michael K
Published: October 2006

The mechanism of oxidation of 4‐hydroxyindolyl‐3‐methyl glucosinolate (4‐hydroxyglucobrassicin) has been investigated using 4‐hydroxyindole as a model compound. By trapping the reactive intermediate with aniline, the oxidation has been shown to proceed via the formation of the indole (4, 7) para‐quinone.
A simplified X‐ray fluorescence (XRF) procedure for the determination of sulphur in graminaceous materials
Authors: Reynolds Stephen B , Martin Andrew D E , Bucknall Brian , Chambers Brian J
Published: October 2006

An automated, rapid and much simplified XRF procedure for assessing total sulphur in graminaceous plant materials is described. Sample preparation has been refined and microprocessor control incorporated to provide considerable savings in analytical time.

The procedure has been tested using samples from two grass‐silage cuts, taken from an ADAS (Agricultural Development and Advisory Service) trial studying responses, under intensive grassland management, to sulphur and nitrogen applications. Good correlation between XRF and wet chemical analysis was achieved, and sample turnround was markedly increased. The method produced accurate results for both cuts with high precision and reproducibility where careful attention was paid to sample homogeneity and disc preparation. The potential for wider application of XRF techniques to elemental analysis of agricultural materials is discussed.
GC and HPLC of grape monoterpenyl glycosides
Authors: Bitteur Sylvaine , Günata Ziya , Brillouet Jean‐Marc , Bayonove Claude , Cordonnier Robert
Published: October 2006

The aim of the present study was to find a method alternative to enzymic hydrolysis for the analysis of grape terpenyl glycosides. GC after trimethylsilane derivatisation, and HPLC on four different stationary phases, ie bare silica, aminopropyl‐, diol‐ and octadecyl‐bonded silicas, were in turn considered for the separation of these aroma precursors extracted from grape juice, and specific enzymic hydrolyses with highly purified glycosidases showed which were the major components. These investigations show that reversed‐phase liquid chromatography is better suited for both the direct and individual analysis of these glycosides.
Studies with volunteers on the role of histamine in suspected scombrotoxicosis
Authors: Clifford Michael N , Walker Ronald , Wright John , Hardy Roy , Murray Charles K
Published: October 2006

The results are reported of single‐blind, medically supervised studies in volunteers of the association between the histamine content of mackerel and the incidence of scombrotoxicosis. Volunteers consumed 25 or 50 g of fresh or spoiled mackerel containing varying quantities of endogenous or added histamine. In one study the ability of HI and H2 histamine antagonists to modify symptoms was investigated. Objective parameters (pulse rate, skin temperature and peak expiratory flow rate) were recorded for 6 h, and subjective parameters (headache, flushing, oral tingling, visual disturbances, abdominal pain, nausea, palpitations, wheeziness, diarrhoea, flatulence, shivering and miscellaneous) for 24 h. No significant effects were observed, even with portions of spoiled mackerel containing 300 mg histamine, or mackerel from a batch which was reported to have been associated with an incident diagnosed as scombrotoxicosis.

It is concluded that the precise combination of circumstances required to cause a scombrotoxic event were not reproduced in these studies, but it is tentatively concluded that histamine alone is unlikely to be the causative agent.
Residual peroxidase activity as influenced by blanching, SO2 treatment and freezing of cauliflowers
Authors: Ramaswamy Hosahalli S , Ranganna S
Published: October 2006

The influence of blanching time and SO2 treatment on the residual peroxidase activity and its implication for the sensory quality of frozen cauliflowers were assessed after storage for up to one year at −18°C. The treated cauliflowers, sealed in polythene bags, were placed in waxed paperboard cartons and frozen in a contact plate freezer at −35°C. The sensory quality of frozen stored cauliflowers related well to their residual peroxidase activity, which was sensitive to the SO2 treatment. Blanched cauliflowers following a brief dip in a metabisulphite solution prior to freezing gave a significantly (P<0.05) superior product even when stored for one year. The residual peroxidase activity, which ranged from 1 to 5.5% in the blanched samples, was below 1 % in the SO 2‐treated samples, and the SO2 content of50 ppm found in these stored samples disappeared after 3 min cooking in boiling water.
An investigation of ripening and handling strategies for early season kiwifruit (Actinidia deliciosa cv Hayward)
Authors: Lallu Nagin , Searle Ann N , Macrae Elspeth A
Published: October 2006

Several strategies for ripening and handling early season kiwifruit (Actinidia deliciosa (A Chev) Liang et Ferguson cv Hayward) were investigated. Fruit were harvested from the same block of mature vines of kiwifruit in 1985 and 1986, when fruit had reached 5.5 and 6.2% w/v soluble solids concentration (SSC), and treated with ethylene (1 ml litre−1, 12h, 20°C), either before or after cool storage at 0°C for either 4 or 6 weeks. In addition, the effect of short delays at 20°C and/or ambient temperatures (16–21°C) for up to 5 days prior to ethylene treatment, and the effect of short delays at 20°C for up to 96 h after ethylene treatment prior to cool storage, were assessed.

Fruit softening in response to ethylene treatment comprised two phases: a rapid phase lasting 3 to 4 days during which flesh firmness decreased from a harvest firmness of 8–10kgf (kgf × 9.807=N) to approximately 1.5–2kgf, followed by a second, slower phase during which flesh firmness decreased from 2 kgf to an eating firmness of approximately 0.7kgf. Softening was more rapid and uniform in response to ethylene treatment, irrespective of fruit maturity or prior treatment. Delays at ambient temperature and/or 20°C prior to ethylene treatment had no effect on subsequent softening rates. Fruit which had been cool stored at 0°C after ethylene treatment continued to soften but at reduced rates relative to fruit held at 20°C. Increasing delays at 20°C prior to cool storage decreased subsequent storage and shelflife. Softening and ripening rates were similar in fruit of different maturity indices in 1985 but not in 1986. Fruit harvested at 5.5% SSC always had acceptable eating quality if treated with ethylene.

The results indicate that several ripening and handling strategies are possible for early season kiwifruit. However, an appropriate maturity index is required to determine how early fruit should be harvested if fruit are to be treated with ethylene for early season marketing.
Maturation of kiwifruit (Actinidia deliciosa cv Hayward) from two orchards: Differences in composition of the tissue zones
Authors: Macrae Elspeth A , Bowen Judith H , Stec Margaret G H
Published: October 2006

In a study on fruit maturation in kiwifruit (Actinidia deliciosa ( A Chev) Liang et Ferguson cv Hayward) fruit were harvested from orchards in two growing regions at fortnightly intervals from late March to early May. Soluble solids concentration (SCC) and flesh firmness of whole fruit were measured. Fruit samples were subdivided into three tissue zones: outer and inner cortex and core. Starch and the major sugars and acids in each zone were analysed. Other fruit were ripened with ethylene and evaluated for eating acceptability.

There were major differences in carbohydrate and acid concentrations between the different tissue zones of the fruit, in particular in inositol, starch, and quinic and citric acid concentrations.

The major differences between fruit from the two orchards were in total starch concentration and in the pattern of change in starch in the core. The citric/quinic ratio and malic/quinic ratio in the inner cortex and core also differed between fruit from the two orchards during the harvest period, although both followed the same trends with maturation. Both the sugar/starch and the sugar/acid ratios of the inner cortex differed between fruit from the two orchards at later stages of fruit maturation.

The eating quality of the fruit from both orchards harvested in late March and early April at 4.5 and 4.8 % w/v SSC respectively was unacceptable, but all other fruit were found to be acceptable. Unacceptable fruit had a low flavour intensity, and a moderate level of off‐flavours. The flesh texture was relatively mealy/grainy.

The conditions under which fruit mature can cause differences both in the acid balance and the relative amounts of sugars and starch. The tissue zones also show different patterns of change during maturation. These differences may affect both the final eating quality of the fruit and the manner in which the fruit ripen after harvest.
Relationship between density and stiffness of apple flesh
Authors: Vincent Julian F V
Published: October 2006

The parenchyma of a number of varieties of apple was tested in torsion. It is necessary to use small samples (cylinders 10 mm long × 5 mm diameter) orientated to take account of the radial air spaces. Over a range of nine varieties of apple, the torsional stiffness (0.5 to 7 MPa) is largely dependent on the average density (0.6 to 0.9 g cc−1) both within and between varieties. At a given density, the outer parenchyma is stiffer than the inner. As the apple matures, density and stiffness reduce and their mutual dependence is also less. A model is presented which can convert density (or volume fraction) of packed cells into the degree of mutual cellular contact. The calculated degree of contact (never greater than 0.4 of the wall area of a cell) correlates well with stiffness, though the nature of the correlation varies with the variety of apple and its maturity. The anisotropy and density/stiffness relationship must be considered in any mechanical (and presumably, therefore, organoleptic) testing of apples.
Cinnamic acid–carbohydrate esters: An evaluation of a model system
Authors: Bohn Peter J , Fales Steven L
Published: October 2006

Chemical esterification of cinnamic acids to cell walls has been proposed to simulate the negative effect of these acids on fibre digestion by ruminants. In this model a spontaneous reaction between an acid chloride and a free hydroxyl group forms an ester linkage between p‐coumaric acid (PCA), for example, and cell wall carbohydrates. This study was conducted to evaluate that system. Esterification of p‐coumaric acid (PCA) to switchgrass (Panicum virgatum L) neutral detergent fibre (NDF) significantly (P <0·05) increased PCA concentration 12·3 to 32·7 mg g−1 NDF and reduced (P <0·05) NDF digestibility from 385·4 to 244·4 mg g−1 NDF. Treated NDF (0, 50, 100 mg PCA g−1 NDF) was sieved through screens with diminishing mesh size in order to isolate fractions with increasing surface area per unit mass. Measured PCA concentration was 50% greater in PCA‐treated fractions isolated by 0.11‐mm mesh than in fractions isolated by 0·50‐mm mesh, suggesting that esterification of PCA occurred predominantly at the surface of the particle. In addition, at the highest level of PCA treatment, digestibility of the fraction isolated from the smallest mesh sieves was 17% greater than that of the material from the largest mesh sieve. The predominant placement of PCA on the particle surface constitutes a major limitation of this technique. Other serious limitations include the potential for polymerisation of cinnamic acids with free hydroxyl groups prior to esterification to fibre, and the non‐specific placement of the ester linkages on the fibre. All three factors cause the model fibre to depart substantially from the characteristics of plant cell wall.
Fatty acid and glyceride composition of Astrocaryum vulgare kernel fat
Authors: Oboh Fred Omon , Oderinde Rotimi A
Published: October 2006

The kernel composition, lipid classes, fatty acid composition, fatty acid distribution on triglycerides and triglyceride composition of kernel fat from Astrocaryum vulgare Mart palms grown in Nigeria have been studied. Kernels had a high fat content. Lauric acid was the predominant fatty acid in the whole fat and was also the major fatty acid in the triglycerides and in the 2‐monoglycerides derived from them by pancreatic lipase hydrolysis. All the fatty acids exhibited a preference for the 1‐and‐3, positions of triglycerides, except for lauric which showed a preference for the 2‐position and oleic which exhibited a random distribution. The trisaturated triglycerides were the predominant triglyceride type and the fatty acid composition of the various triglycerides suggested an absence of completely unsaturated triglycerides.
Variation of chemical composition data of agricultural and forest fibrous by‐products as determined by the two detergent systems of analysis
Authors: Rebolé Almudena , Alvira Pilar , González Gaspar
Published: October 2006

The growing use of agricultural and forest by‐products as ruminant feed, and of the detergent system to determine their feeding value, makes it of interest to compare direct and sequential detergent analyses in order to examine the differences between them and the extent of accuracy.

The chemical composition of cereal straws (oat, barley, rye, wheat, maize) and legume straws (fenugreek, pea‐grass, lupin, pea and bean), grapevines, fenugreek bagasse and poplar bark was determined by applying both methods. Lignin (measured as permanganate lignin) and cellulose (measured as sulphuric acid cellulose) showed the greatest differences (2·0 and 3·2%, respectively). Tannins (1·5% of DM) and cell‐wall protein (2·0% of DM) could account for the discrepancy between both routines of analysis and for that between both lignin procedures.
Organochlorine pesticide residues in domestic fowl (Gallus domesticus) eggs from central Kenya
Authors: Mugambi John M , Kanja Laetitia , Maitho Timothy E , Skaare Janneche U , Lökken Per
Published: October 2006

In 367 domestic fowl (Gallus domesticus) eggs collected from 61 farms, residues of 10 pesticides were detected in various combinations and in the following order of frequency: p,p′‐DDE (in 100% of the eggs), p,p′‐DDT (98%), dieldrin (95%), Indiane (66%), p,p′‐DDD (46%), o,p′‐DDT (17%), β‐HCH (9%), γ‐HCH (5%), endrin (4%) and aldrin (0–5%). No residues of heptachlor, heptachlor epoxide, HCB or PCBs were found. The mean concentration (0–70 mg kg−1 eggs; range <0–01–10–25) of total DDT exceeded the extraneous residue limit (ERL) of 0–50 mg kg−1. The mean dieldrin residue level (0–35 mg kg−1; range 0–01–14–90) was 3–5 times higher than the ERL (0–10 mg kg−1). Only 3% of the eggs exceeded the ERL for Indane. The 156 eggs from free‐range hens had significantly (P<0–05) higher residue concentrations of total DDT, dieldrin and Iindane than eggs collected from hens kept in enclosures. The mean ratio [p,p′‐DDT]/[p,p′‐DDE] in eggs from enclosed hens (0–97) was significantly higher (P<0–01) than in eggs from free‐range hens (0–53), indicating that the former had a more direct exposure to p,p′‐DDT, whereas the latter obtained more of it after environmental conversion to p,p′‐DDE. Eggs from a rice‐growing area had the highest concentrations of all pesticide residues detected. Accumulation ratios indicated that the levels of DDT and Iindane in the feed of enclosed hens could account for the levels in the corresponding eggs. The much higher accumulation ratios calculated for the free‐range hens demonstrated that the feed ingested by these chickens obviously contained ingredients additional to those sampled, and revealed probable extensive environmental contamination by these persistent pesticides. The present results indicate that there is a need to identify sources of dieldrin in the eggs of domestic fowls and, where necessary to investigate local wildlife samples. The amounts of total DDT and dieldrin in eggs in this study seem to be higher than reported from any other country. Toxicological evaluation of the results indicates that, at lest in parts of KEnya there is a need for improved practices in the use of some organochlorine pesticides.
Purification of glutathione S‐transferase from lamb muscle and its effect on lipid peroxidation
Authors: Williamson Gary
Published: October 2006

Lamb muscle contained 0.4 mg glutathione S‐transferase (EC 2.5.1.18) per gram of tissue. On storage at 1°C, 20% of the activity was lost after 3 weeks. Glutathione S‐transferase was isolated from lamb muscle by affinity chromatography on S‐hexyglutathione Sepharose 6B. One major form of the enzyme was present in the purified preparation, a dimer with subunit molecular weight of 22 900 and isoelectric point of 6.7. This enzyme fits into the Pi class on the basis of substrate specificity. Linoleic acid hydroperoxides and trans, trans‐2,4‐decadienal, products of linoleate peroxidation, were both substrates (0.11 and 0.24 μmol min−1 mg−1 protein respectively). Glutathione S‐transferase inhibited copper‐stimulated peroxidation of arachidonate in the presence of glutathione. The inhibition was only slightly less efficient in the absence of glutathione. The latter effect probably arises from the presence of enzyme‐bound glutathione (4–5 mol mol−1 enzyme subunit) and also from a small but significant glutathione‐independent peroxidase activity. The latter was detected using an HPLC assay which monitors formation of product directly. Reduced glutathione per se showed only a slight inhibition of arachidonate peroxidation.
Uptake of foliar‐applied urea by winter wheat (Triticum aestivum): The influence of application time and the use of a new 15N technique
Authors: Powlson David S , Poulton Paul R , Møller Niels E , Hewitt Michael V , Penny Alexander , Jenkinson David S
Published: October 2006

A new 15N technique (termed the negative discard method) for measuring recovery of foliar‐applied N by crops in the field is described. 15N‐labelled fertiliser solution is sprayed on to a small area of crop, using a hand sprayer, while the surrounding area is sprayed with unlabelled N at the same rate. An area considerably larger than that given 15N is harvested with a small‐plot combine‐harvester, and crop recovery of foliar‐applied N is calculated from the 15N enrichment of the resulting sample containing a mixture of labelled and unlabelled material.

The technique was used to measure recovery of N from 15N‐labelled urea solution sprayed on to winter wheat (Triticum aestivum L cv Avalon) at six different times from growth stage 39 (3 weeks before anthesis) to growth stage 73 (2 weeks after anthesis). Each treatment of 40 kg N ha−1 was divided into two equal portions, the second being applied 1–2 days after the first, to minimise the risk of leaf damage. The crop had earlier received 210 kg N ha−1, as ‘Nitro‐Chalk’, in spring (50 kg ha−1 at growth stage 22 and 160 kg ha−1 at growth stage 31) which was more than sufficient to achieve maximum grain yield. At harvest, 70% of the foliar‐applied N given at anthesis (growth stage 65) was recovered in the above‐ground crop, including 64 % in grain. The proportion of labelled N recovered in the grain (92% of that in the above‐ground crop) was slightly greater than with soil‐applied N given earlier in the growing season. Recovery of foliar‐applied N was slightly less for the earliest (growth stage 39) and latest (growth stage 73) times of spraying: 64% and 58% in above‐ground crop, and 56% and 54% in grain, respectively. All of the foliar applications of 40 kg N ha−1 increased %N in grain to the same extent as an additional 40 kg N ha−1 applied to soil in spring.
Effect of ochratoxin A on some biochemical changes in seeds of mung bean (Vigna radiata, var Pusa 119
Authors: Sinha Kaushal K , Kumari Punam
Published: October 2006

The effect has been studied of a range of concentrations of ochratoxin A on some biochemical parameters, viz chlorophyll, protein and nucleic acid concentrations during seed germination and seedling growth in mung beans (Vigna radiata (L) Wilczek, var Pusa 119). Reduction in levels of all the parameters resulted from ochratoxin A treatment, and the extent of reduction was directly influenced by the concentration of toxin applied.
Oxalate in vegetable Amaranth (Amaranthus gangeticus). forms, contents, and their possible implications for human health
Authors: Vityakon Patma , Standal Bluebell R
Published: October 2006

Forms of oxalate in Amaranthus gangeticus L (a vegetable amaranth) grown in three sites with different soil and climatic factors were identified, and their contents were determined. On average the total oxalate content was 91 g kg−1 on a dry weight basis. This is high when compared with the amounts reported to be a health hazard in other vegetables and forage crops. Two dominant fractions of oxalate in amaranth were isolated: a fraction soluble in boiling water which was predominantly in the form of potassium and magnesium oxalate, and an associated insoluble residue which was predominantly calcium oxalate.

Most of the Ca in amaranth is unlikely to be available to the body. A suggestion was made that research on reducing the oxalate content of amaranth should first be directed at soluble oxalates because they can interfere with Ca availability from other food sources.
Lactose hydrolysis in acid whey with subsequent glucose isomerisation
Authors: Abril J Ruben , Stull J Warren
Published: October 2006

The disposal of whey is a problem because of its high biological oxygen demand. Of the 1.8 × 1010 kg produced annually in the USA, only about half has any food or feed application (Jelen 1983). One possible approach to acid whey utilisation is the removal of the proteins either by ultrafiltration or by thermal precipitation, hydrolysis of lactose with soluble β‐galactosidase (lactase, EC 3.2.1.23) and subsequent isomerisation of the glucose to fructose by the action of immobilised glucose isomerase (EC 5.3.1.5). The resulting syrup is composed of glucose, fructose and galactose plus small amounts of unhydrolysed lactose and other oligosaccharides. The syrup was found to have a predominantly sweet and slightly salty taste. Recently sucrose has been replaced in many foods by high fructose corn syrup produced by the action of glucose isomerase on glucose syrups from corn starch hydrolysates (Bucke 1981). The whey syrup also has potential as a sucrose substitute.
Rapid α‐amylase assays for assessment of pre‐harvest sprouting damage in wheat
Authors: Henry Robert J
Published: October 2006

Rapid specific α‐amylase assays were developed for use in the assessment of pre‐harvest sprouting damage in wheat. Two different commercially available α‐amylase substrates, an insoluble cross‐linked dye‐labelled starch and a soluble blocked p‐nitrophenyl maltoheptaoside, were investigated. Extraction of α‐amylase from ground wheat was shown to be very rapid. Assays were simplified and speeded up by including the substrates in the extraction medium. Action on the substrates in the extraction medium for 2 min was used to estimate α‐amylase activity. Results for the rapid methods correlated well with those obtained in assays with separate extraction and assay steps and the Falling Number test. The assay with the insoluble substrate could be conducted at higher temperatures and was thus more sensitive. These assay procedures have potential for application in assessing sprouting damage for segregation of damaged wheat in commercial production.
FT‐IR investigation of lignin components in various agricultural lignocellulosic by‐prod
Authors: Buta J George , Galletti Guido C
Published: October 2006

Fourier transform infrared spectra of eight lignocellulosic by‐products (wheat and barley straws, soya bean pod walls and stems, alfalfa stems, corn cobs and stalks and red oak leaves) were obtained. Relative differences in absorption intensity but not maxima in the lignin region were found. Absorption maxima were obtained by use of second derivatives of the spectra, while differences in absorption intensities were best compared by use of first derivatives.
Effect of proteinase inhibitors from potato on the quality of stored herring
Authors: Aksnes Anders
Published: October 2006

Autolytic processes are important factors in the deterioration of fish material. The effect of proteinase inhibitors from potato tubers in inhibiting the proteolysis in stored, ground herring was studied. Using an extract from potato, which was found to contain inhibitors for trypsin, chymotrypsin, carboxypeptidase A and carboxypeptidase B, the autolysis as measured by TCA‐soluble protein was profoundly decreased, as were the contents of free amino acids. The potato extract preserved the contents of total arginine, tyrosine and lysine in the samples of stored herring, and the levels of histamine, putrescine, tyramine and cadaverine were reduced. The addition of proteinase inhibitors gave a somewhat lower content of total volatile nitrogen, and the total viable count of bacteria was reduced to some extent.
Some compositional changes in malted sorghum (Sorghum vulgare) grain and its value in broiler chicken diet
Authors: Okoh Patrick N , Kubiczek Roman P , Njoku Placid C , Iyeghe Grace T
Published: October 2006

Grains of two sorghum (Sorghum vulgare L) varieties were germinated at room temperature for 2, 4 and 6 days. Germination resulted in an increase in protein content due to dry matter loss; this rose with increasing time of germination. The absolute amount of tannin was unchanged until the fourth day of germination but decreased markedly by the sixth day. Fractionation of the grain protein of one variety showed that there was a large increase in the albumin‐globulin fraction (rich in lysine) and a decrease in the kafirin and cross‐linked kafirin fraction (low in lysine) as a result of germination. Although these changes resulted in a more than 30% increase in lysine content on the fourth and sixth days of germination, a substantial loss in dry matter occurred when germination was continued up to 6 days.

When 14‐day‐old Hubbard chicks were fed a diet containing about 59% malted sorghum supplemented with lysine, they showed better (P < 0.05) weight gain and efficiency of feed conversion than those on malted sorghum without lysine supplementation. However, malting reduced the amount of lysine needed to supplement the diet from 0.25% for unmalted sorghum to 0.18% for malted sorghum.
Effect of chlorothalonil application frequency on quality factors of peanuts (Arachis hypogaea)
Authors: Sanders Timothy H , Gorbet Daniel W , Shokes Fred M , Williams E Jay , McMeans Jack L
Published: October 2006

Yield, disease rating, seed quality and seed size parameters were determined from four peanut (Arachis hypogaea L)genotypes with different levels of resistance to leafspot to evaluate the effects of controlling peanut leafspot with chlorothalonil. In 1981 and 1983, main plot treatments were (i) no fungicide applications, (ii) applications of chlorothalonil (1242 g ai ha−1) at 14‐day intervals, and (iii) applications of chlorothalonil (1242 g ai ha−1) at 20‐day intervals. After shelling, a narrow seed size range (<8.33 mm ≤7.14 mm width) was used to reduce maturity effects in analyses of free fatty acids, total carbonyls, carbohydrates, oil content, and fatty acid profile. Oil content increased significantly with spray frequency in both years only in Southern Runner, and treatment differences in all genotypes were no more than 1.7%. Oleic and linoleic acid decreased and increased, respectively., with increased spray frequency in Florunner (susceptible) and the resistant genotype with the highest unsprayed disease rating. Florunner median seed size for the unsprayed treatment (8.07 mm) was significantly smaller than the median sizes for the 20‐day interval (8.15 mm) and 14‐day interval (8.16 mm) treatments.
Physical properties of keropok (fried crisps) in relation to the amylopectin content of the starch flours
Authors: Mohamed Suhaila , Abdullah Norakiah , Muthu Mangayar Karasi
Published: October 2006

The physical characteristics of keropok made from various flours (glutinous rice, rice, wheat, sago, tapioca and corn) were studied. The amount of water used to wet the flour in the initial stages of making the keropok was very important, since it affected the linear expansion, oil absorption, elasticity and crunchiness of the resultant fried crisps. Linear expansion, oil absorption and elasticity were positively correlated to the total amylopectin content in the whole flour (r2 = 0.99, 0.97 and 0.97 respectively). The best fitted lines for prediction of linear expansion, oil absorption and elasticity of the fried crisps were 21y ≦ 0.35x ‐ 162, y=0.15x‐ 74 and y=0.0008x‐0.41 respectively, where x is the amylopectin content of the whole flour. Good keropok can be made from any starch‐rich flour that contains a high proportion of amylopectin. These starches can be recognised physically by their clarity on gelatinisation, stability to retrogradation, low resistance to shear and high cold‐paste viscosity. The addition of mung bean flour to tapioca flour helped increase the protein content and flavour of the keropok; it also reduced the oil absorption of the keropok during frying. Although linear expansion decreased with increasing mung bean flour content, the substitution of up to 600 g kg−1 mung bean flour was acceptable since the linear expansion of mung bean/tapioca crisps remained above 35%. The experimental values for linear expansion of mung bean/tapioca crisps correlates very well (r2 = 0.99) with the predicted linear expansion based on the amylopectin content of the combined flours. Legume crisps, being high in protein and fibre, are a possible cheup alternatiue to fish crisps for the production of a nutritious snack food for growing children.
Determination of the previous maximum temperature of heat‐treated minced meat by near infrared reflectance spectroscopy
Authors: Isaksson Tomas , Ellekjær Marit H R , Hildrum Kjell I
Published: October 2006

Determination of the heat treatment given to minced meat has been explored on a preliminary basis by near infrared reflectance (NIR) analysis. Minced meat samples from beef were heated at five different temperatures from 50 to 95°C. Correlating NIR‐determined temperatures ranging against actual laboratory treatment temperatures gave correlation coefficients of 0.987 for ‘wet’ meat and 0.992 for freeze dried meat samples. The minimum root mean square of determination errors obtained were 3.9°C for ‘wet’ meat and 2.5°C for freeze dried meat samples.