bluuebunny/crossref_metadata_2025 huggingface dataset:
Fatty acid composition of 20 lesser‐known Western Australian seed oils
Authors: Rao K Sundar , Sino D
Published: October 2006

The fatty acid composition of the seed oils of Compositae (eight species), Proteaceae (four species), Begoniaceae (one), Boraginaceae (one), Euphorbiaceae (one), Liliaceae (one), Meliaceae (one), Rhamnaceae (one), Sapindaceae (one) and Stylidaceae (one) were qualitatively and quantitatively determined by a combination of thin layer chromatography and gas liquid chromatography. The seeds contained oil in the range 1.6‐37.7% (on a dry basis). Unusual fatty acids were not found. The major fatty acids were oleic and linoleic in all the species of seed oils except one (Phyllanthus calycinus) in which linolenic acid was the major component.
Comparative study of the nutritive value of casein heated by microwave and conventionally
Authors: Jonker Diana , Penninks André H
Published: October 2006

The objective of this study was to compare the net protein utilisation, digestibility and biological value of casein solution heated by microwave or conventionally, ie on an electrically heated plate. Portions (500 ml) of an aqueous solution of casein (100 g litre−1) were heated to a temperature of 80°C and subsequently kept at 80± 5°C for 2 min. The heating times of microwave and conventional heating were the same. Additional portions were subjected to a so‐called abused treatment consisting of repeating the normal microwave or conventional heat treatment three times. Next, the nutritive value of heated and unheated casein was determined in a 10‐day feeding study with Wistar rats. The net protein utilisation, digestibility and biological value of unheated casein were 61.1, 100 and 61%, respectively. Comparable values were obtained for casein heated by microwave or conventionally. These results did not therefore indicate any decrease in nutritive quality of the protein by microwave heating or conventional heating under simulated household conditions.
Chemical composition and protein quality of newly released groundnut (Arachis hypogaea L ) cultivars
Authors: Jambunathan Ramamurthi , Gurtu Santosh , Raghunath Kooram , Kannan Seetha , Sridhar Rudravarapu , Dwivedi Sangam L , Nigam Shyam N
Published: October 2006

Five groundnut (Aruchis hypogueu L) cultivars developed by the International Crops Research Institute for the Semi‐Arid Tropics (ICRISAT) and two local cultivars as controls were grown in post‐rainy and rainy seasons at Patancheru, India. They were analysed for their proximate composition, minerals and trace elements, amino acid composition, true protein digestibility (TD), biological value (BV), net protein utilisation (NPU), and protein efficiency ratio. One‐hundred seed mass, protein content and TD were significantly higher in the post‐rainy season while starch, sugars, BV and NPU were significantly higher in the rainy season. Post‐rainy cultivars exhibited higher concentrations of potassium, calcium, iron and several essential and non‐essential amino acids. TD of blanched groundnut was better than that of the whole seeds. The composition and protein quality of ICRISAT cultivars were comparable to those of the controls.
Lignification of switchgrass (Panicum virgatum) and big bluestem (Andropogon gerardii) plant parts during maturation and its effect on fibre degradability
Authors: Jung Hans‐Joachim G , Vogel Kenneth P
Published: October 2006

Five cultivars of switchgrass (Panicum virgatum L) and four cultivars of big bluestem (Andropogon gerardii Vitman) were harvested at vegetative, boot and heading stages of maturity. Leaf and stem fractions were analysed for detergent fibre composition and 48‐h ruminal in‐vitro degradability, ester‐ and ether‐linked non‐core lignin phenolic acids, and core lignin composition. Big bluestem leaves contained more neutral detergent fibre than switchgrass, but general composition of the fibre did not differ. Stem fibre of switchgrass had relatively lower levels of cellulose and lignin at the vegetative stage than observed in big bluestem. Esterified and etherified p‐coumaric and ferulic acid concentrations were generally higher in switchgrass plant parts. Yield of nitrobenzene oxidation products from core lignin was greater for switchgrass leaves, but very little difference in composition was noted. Leaf tissue contained lower concentrations of all lignin components than stems. Maturation resulted in increased total lignification, but all components did not respond in the same manner. Variation for all measures of lignification seemed to be as great within species as between the grass species. Degradability of fibre declined with maturation. The only species difference was that switchgrass fibre was more degradable at the vegetative stage. Relationships between lignification and fibre degradability were in agreement with some, but not all, previously reported relationships. Concentration of core lignin was only a significant predictor of fibre degradability when the relationship was examined across maturity stages. Within a stage of maturity, lignin composition was more closely related to fibre degradability than was concentration. However, the best predictors of fibre digestibility differed among species, plant part and maturity.
Apparent inhibition to digestion by lignin in normal and brown midrib stems
Authors: Thorstensson Elisabet M G , Buxton Dwayne R , Cherney Jerome H
Published: October 2006

Lignin, a cell wall component, limits digestibility of plant cell walls. Brown midrib (bmr) mutants of forages have lignin with altered chemical composition compared with their normal counterparts. The objectives of this study were to determine if bmr lignin is more inhibitory to digestion than is normal lignin and if bmr has a consistent effect on rate of digestion across species and environments. Extent and rate of in‐vitro cell wall digestion of normal and bmr stems of sorghum (Sorghum bicolor (L) Moench, two comparisons), millet (Pennisetum americanum (L) Leeke) and maize (Zea mays L, two comparisons) were determined. Samples were incubated in rumen fluid, and data were fitted with a first‐order, nonlinear model to estimate concentrations of potentially digestible neutral detergent fibre (PDNDF), digestion rate of PDNDF, concentration of indigestible residue (IR), and lag time before digestion. The NDF, acid‐detergent fibre (ADF), and acid‐detergent lignin (ADL) analyses were conducted sequentially on undigested samples. The IR: ADL ratio was 37% greater for bmr than for normal plants, which indicates that bmr lignin inhibits digestion more than normal lignin per unit of lignin. Digestion rate of PDNDF was faster in bmr than in normal counterparts in one of the two sorghum comparisons (difference of 59%) and in the millet comparison (difference of 27%), but in neither maize comparison. The bmr mutants were lower than normal genotypes in NDF (9%) and ADL (47%) concentrations. The PDNDF concentration was 19% greater for bmr than for normal lines. Thus, decreased lignin concentration in bmr mutants increased the extent of NDF digestion but did not consistently increase the rate of digestion.
Physiological studies on the solid‐state quinoa tempe fermentation, using on‐line measurements of fungal biomass production
Authors: Peñaloza Walter , Davey Christopher L , Hedger John N , Kell Douglas B
Published: October 2006

A quantitative approach to the on‐line measurement of fungal biomass, based on the biomass‐dependent changes in electrical capacitance at 0.30 MHz, was exploited to optimise the solid‐substrate tempe fermentation of Chenopodium quinoa Willd by Rhizopus oligosporus Saito. Variables including the mould strain, the initial pH, the inoculum density and the substrate moisture content influenced the mycelial development and quality of quinoa tempe prepared in petri dish fermentation units. It was found that R oligosporus isolate UCW‐FF8001 at an inoculation density of 3.3 × 104 colony forming units per gram of quinoa substrate at 620 g kg−1 moisture content yielded both the highest biomass and the best quality tempe.
Effect of aqueous ethanol washing on the physicochemical and functional properties of safflower (Carthamus tinctorius) seed proteins
Authors: Tasneem Razia , Prakash V
Published: October 2006

Defatted safflower seed flour was deliganded by repeated extraction with 750 ml litre−1 ethanol. This reduced the colour/ligand concentration to less than 1% of the original concentration. As a result of this the protein concentration increased from 585 to 686 g kg−1 after deliganding. The proteins from the deliganded flour comprised four protein fractions, as observed from the gel filtration profile and sedimentation velocity pattern. However, the polyacrylamide gel electrophoretic pattern indicated six protein bands. Functional properties such as bulk density and water absorption capacity increased after deliganding. The fat absorption, emulsification and foaming properties showed a decreasing trend as a result of deliganding.
Thermal stability of black turtle soup bean (Phaseolus vulgaris) lectins
Authors: Bonorden William R , Swanson Barry G
Published: October 2006

A method for determining the thermal stability of porcine thyroglobulin (PTG)‐binding lectins in whole black turtle soup beans (Phaseolus vulgaris L) is described. The procedure utilises PTG‐Sepharose affinity chromatography and the Folin‐Ciocalteau protein assay.

The majority of lectin activity in whole black turtle soup beans was destroyed by heating presoaked beans at 97.8°C for 10 min whereas unsoaked beans required 20 min of heat treatment at 97.8°C. Residual lectin activity was eliminated by thermally processing the presoaked and unsoaked beans for 25 and 50 min at 97.8°C, respectively. Thermal inactivation of the lectin in the whole seed is a biphasic, first‐order reaction mechanism.

Lectin‐rat intestinal epithelial cell binding studies indicated the presence of a second lectin in the BTS albumin protein fraction. The lectin lacked an affinity for PTG and was inactivated by heating unsoaked whole beans for 50 min at 97.8°C.
Trimethylamine N‐oxide demethylase (TMAO‐ase) of saithe (Pollachius virens) Kidney: A study of some physicochemical and enzymic properties
Authors: Joly Agnes , Cottin Patrick , Han‐Ching Luçay , Ducastaing André
Published: October 2006

TMAO‐ase is an enzyme of great economic significance in the fish industry since, even below the freezing point, it can produce large amounts of formaldehyde. During frozen storage the resulting formaldehyde‐protein interactions induce deleterious effects on the functional properties of frozen fish minces. Knowledge of the structural and enzyme properties is incomplete at present and produces certain ambiguities. A new procedure for extracting TMAO‐ase from saithe kidney (Pollachius virens (L.)), using a non‐denaturing detergent, has been developed. Subsequent anion exchange chromatography separated three independent enzyme fractions, differing mainly in their isoelectric points (5.0, 4.5 and 4.1). The three fractions revealed identical pH optima for activity (pH = 5.10), affinity constants (12 mM) and activation energies (4 kcal mol−1). However, differences were observed concerning some of their physicochemical properties such as T1/2 denaturation and spectrophotometric characteristics (unusual absorption at λ = 258 nm, related to the presence of DNA fragments). From a structural point of view, as evidenced by the elution profiles, TMAO‐ase activity seems to be constituted of high MW protein groups (20 × 106 and 2 × 105) closely associated with mixed micelles of phospholipids.
Proteinase inhibitors of redgram (Cajanus cajan)
Authors: Mulimani Veerappa H , Paramjyothi S
Published: October 2006

Proteinase inhibitory activity of 35 varieties of redgram (Cajanus cujun L) was determined. Chymotrypsin inhibitory activity was more pronounced than trypsin inhibitory activity in all redgram varieties tested. Both trypsin and chymotrypsin inhibitory activities were found to be markedly reduced on germination.
Protein nitrogen, peptide nitrogen and free amino acid nitrogen in endogenous digesta nitrogen at the terminal ileum of the rat
Authors: Butts Christine A , Moughan Paul J , Smith William C
Published: October 2006

The proportions of endogenous protein nitrogen (N), peptide N and free amino acid N in digesta N from the distal ileum of the rat were determined immediately after collection or following storage frozen ( — 20°C and — 196°C). Eighteen growing rats were given a protein‐free diet for 6 days and then euthanased. Samples of digesta were then collected from the terminal 20 cm of ileum. The digesta samples were centrifuged and the supernate was ultrafiltered. Total nitrogen and total amino acids were determined in the precipitate plus retentate (MW> 10 000 Da) and ultrafiltrate (MW < 10 000 Da) fractions, and urea, creatinine, ammonium and free amino acids in the ultrafiltrate. The storage of digesta did not significantly affect the proportions of N‐containing substances in the precipitate plus retentate or ultrafiltrate excepting that ammonium levels in the latter fraction were significantly lower for digesta processed immediately. On average, 67% of the total digesta N was in the precipitate plus retentate fraction and 61% of the total N was protein N. Essential and non‐essential amino acid N comprised 26 and 36%, respectively, of total digesta N in the precipitate plus retentate. On average, the ultrafiltrate fraction contained 33% of the total digesta N, and the total digesta N contained 10.4, 10.6, 1, 1.5, 1.5 and 0.5 g kg−1 free amino acid N, peptide N, urea N, ammonium N and creatinine N, respectively. Nonamino N (urea N + ammonium N + creatinine N) contributed 4% of the total N in the whole digesta. The N from essential and non‐essential amino acids in the ultrafiltrate (free + peptide), expressed as percentages of the total N in the whole digesta, were 8 and 13 %, respectively. On average, 21 % of the total digesta N was present as free amino acid N and peptide N. These findings give support to the application of a proposed method for the determination of total endogenous ileal amino acid excretion under conditions of peptide alimentation.
Proximate composition and functional properties of raw and processed full‐fat fluted pumpkin (Telfairia occidentalis) seed flour
Authors: Giami Sunday Y , Bekebain Dickson A
Published: October 2006

The proximate composition and functional properties of raw, germinated and fermented full‐fat fluted pumpkin (Telfairia occidentalis Hook) flour were studied. Functional properties evaluated by laboratory studies were nitrogen solubility, water and fat absorption, bulk density, foam capacity and stability. Germination increased the crude protein, ash, crude fibre, iron and total phosphorus but decreased the carbohydrate and fat contents. Nitrogen solubility was pH dependent with a minimum at pH 4.0 and a maximum at pH 10.0 for the raw flour. Maximum nitrogen solubility (70%) was recorded for germinated flour, which also showed excellent fat absorption properties. Raw flour was significantly higher (P < 0.05) in water absorption capacity than the processed flours. Germination and fermentation diminished bulk density, foam capacity and stability of fluted pumpkin flour.

Raw full‐fat fluted pumpkin flour showed comparatively better water and fat absorption properties than raw full‐fat soya flour. Hence it may prove to have useful applications in fabricated foods such as bakery products and ground meat formulations.
Assessment of maximum cooking temperatures in previously heat treated beef. Part 1: Near infrared spectroscopy
Authors: Ellekjaer Marit Risberg , Isaksson Tomas
Published: October 2006

Near infrared diffuse reflectance (NIR) and transmittance (NIT) spectroscopy were studied as potential methods for determination of the previous heat treatment of beef. Ninety‐four samples of M longissimus dorsi from 33 bulls were heat treated at nine different temperatures between 50 and 85°C, and analysed by NIR and NIT spectroscopy. The samples were analysed by NIR and NIT in both ‘wet’ and freeze dried states. The NIR and NIT methods were able to determine the maximum temperature of previously heat treated beef with a prediction error of 2.0‐2.1°C in the temperature range 50–85°C. Freeze drying of the samples prior to analysis reduced the prediction error to 1.4°C for the NIR method. NIR and NIT should be useful as fast screening methods to determine whether beef has been adequately heat treated.
Assessment of an in‐situ technique to estimate the degradation of lipids in the rumen
Authors: Perrier Rosine , Michalet‐Doreau Brigitte , Bauchart Dominique , Doreau Michel
Published: October 2006

In‐situ disappearance of alfalfa hay, soybean, soybean meal and maize grain lipids and fatty acids were measured using two dairy cows. Bags were removed after 1, 2, 4 and 8 h incubation. Bacterial colonisation was estimated by labelling bacteria by a 15N infusion into the rumen. Results were then subtracted from calculations. Bacterial dry matter, lipids and fatty acids were highest for alfalfa hay and lowest for soybean. Disappearance of lipids and fatty acids was significantly higher for maize than for the other feeds. Stearic and octadecenoic acids appeared in hay and soybean as products of hydrogenation but no distinction could be made between fatty acids leaving the bags and fatty acids appearing or disappearing due to hydrogenation. Complete linolenic acid hydrogenation seems to be limited by the rate of hydrogenation of stearic acid into octadecenoic acids. Nylon bags seem to be a valuable tool to estimate hydrogenation or protection against hydrogenation in high linolenic content feeds.
Malt characteristics of sorghum vulgare varieties from ghana
Authors: Demuyakor Bawa , Ohta Yoshiyuki
Published: October 2006

Two local varieties, a white type and a red type, of Sorghum vulgare cultivated in Ghana were malted, using a micro‐malting method, and their malt characteristics studied and compared to that of a commercial barley malt. The optimal germination time, at 30°C, to produce a good malt of high diastatic power and extract from local varieties of these varieties was 4‐5 days. The local varieties were also found to have high diastatic activities of between 55 and 68% of the commercial barley malt. Hot‐water extracts of the well malted sorghum varieties were also found to have higher and sustainable amounts of free amino nitrogen than the commercial malt. The hot‐water extracts of sorghum malts were lower than the commercial barley malt, yielding about 66‐77% of the barley malt, but contained a higher glucose to malt ratio. In terms of varietal superiority, the white sorghum yielded higher malt extracts than the red type.
Effect of Steaming and Autoclaving Oak (Quercus incana) leaves on levels of tannins, fibre and lignin and in‐sacco dry matter digestibility
Authors: Makkar Harinder Paul S. , Singh Bhupinder
Published: October 2006

Oak (Quercus incana, Roxb) leaves were subjected to steaming or autoclaving (1.05 kg cm−2) for 10 and 20 min. For the fresh whole leaves, both steaming and autoclaving did not decrease substantially the levels of total phenols (TP), condensed tannins (CT), ellagitannins (ET) and protein precipitation capacity (PPC). At a 1:2 (w/v) ratio of dry ground leaves and water, steaming reduced the TP, CT, ET and PPC by about 10, 29, 30 and 25%, respectively, whereas these values were 27, 54, 64 and 53%, respectively, on autoclaving for 10 min. Increase of treatment time did not increase the reduction in tannin. The reduction of tannin levels decreased on increasing the water content from 1:2 to 1:3 (w/v of leaves to water). The in‐sacco dry matter digestibility increased marginally on steaming or autoclaving. Various fibre fractions and lignin increased following the heat treatments. Proanthocyanidins (PAS) per g neutral‐detergent fibre or acid‐detergent fibre (NDF, ADF) decreased on autoclaving. The PAS in NDF per g leaves was almost similar whereas PAS in ADF per g leaves decreased substantially following autoclaving, suggesting that heat treatment increased the solubility of PAS in an acid‐detergent solution. This can introduce errors in the values obtained for fibre and lignin using detergent system of analysis. The extractability of PAS in 50% aqueous methanol also decreased following autoclaving. The data obtained suggested that this decrease in extractability is probably due to binding of PAS to proteins on heat treatment.
Effect of processing methods on spinach: Proximate composition in fatty acids and soluble protein
Authors: Murcia M Antonia , Vera Ana , Garcia‐Carmona Francisco
Published: October 2006

The proximate composition and fatty acid content of spinach were determined in two processing stages. Crude protein and ash content were 2.89% and 1.96%, respectively. The total lipid content was 0‐61%. The predominant fatty acids were palmitic (16:0), hexadecadienoic (16:2), hexadecenoic (16:1), stearic and hexadecatrienoic (18:0 and 16:3), oleic (18:1), linoleic (18:2) and linolenic (18:3). Little loss was observed as a result of processing. Soluble protein content showed losses of up to 87% during processing.
The influence of saline irrigation and organic waste fertilisation on the mineral content (N, P, K, Na, Ca and Mg) of tomatoes
Authors: Gómez I , Navarro‐Pedreño J , Mataix J
Published: October 2006

Tomato plants were grown in a calcareous soil supplemented with two organic wastes (sewage sludge and epicarp‐mesocarp of the almond tree fruit). They were irrigated at three levels of salinity caused by the addition of sodium chloride. N, P, K, Na, Ca and Mg were determined in the soil and tomato fruits. The treatments had a significant incidence on mineral content in fruit and soil.
Effects of Irradiation and Storage on the γ‐Glutamyl Transpeptidase Activity of Garlic Bulbs cv ‘Red’
Authors: Ceci Liliana N , Curzio Osvaldo A , Pomilio Alicia B.
Published: October 2006

The effects of 50 Gy γ‐irradiation 30 days after harvest on γ‐glutamyl transpeptidase (GTP) activity (the first enzyme in the catabolism of γ‐glutamyl peptides) of garlic bulbs cv ‘Red’ during storage for 300 days were evaluated. GTP activity was determined by spectrophotometry using γ‐glutamyl‐p‐nitroanilide as exogenous substrate, and was correlated with parameters related to the metabolic‐respiratory activity, such as sprouting index in control bulbs, and cumulative weight losses (CWL) and non‐enzymic or control pyruvate (CP; metabolite of the respiratory chain) in irradiated and control bulbs. GTP activity was also correlated with flavour parameters, such as enzymic pyruvate (EP; metabolite of the reaction of alliinase and sulphur amino acids in crushed garlic) and primary sulphur compounds. From these results, three storage stages are suggested: (i) the internal dormancy period, (ii) the first post‐dormant stage, and (iii) the second post‐dormant stage. During the first 90 days of storage (first stage) all the parameters remained nearly constant in the controls, while GTP activity and CP content increased in irradiated garlic because of radioinduced metabolic‐respiratory activation. From 90 to 180 days of storage (second stage) the correlation between the increases of GTP and EP in irradiated garlic and controls was due to the action of GTP on γ‐glutamyl peptides that finally released substrates of alliinase. Both enzymes increased EP contact, which was higher in irradiated garlic (major flavour enhancement) than in controls. After 180 days of storage (third stage) EP and primary sulphur compounds decreased in irradiated garlic and in the controls, while GTP, CWL and CP kept increasing in both samples with lower rates of increase in irradiated garlic. These increases were related to metabolic activation, reserve exhaustion and finally rotting. Therefore, irradiated garlic was of better quality at the end of storage.
Variation of lipid and tocopherol composition in three strains of channel catfish (Ictalurus punctatus)
Authors: Erickson Marilyn C.
Published: October 2006

Three strains of channel catfish (Ictalurus punctatus), which were designated as ‘AQUA’, ‘LSU’ and ‘MSU’, were examined for their lipid and tocopherol composition to delineate if genetic strains exhibited the potential to vary in their susceptibility to lipid oxidation. Since age, diet and environmental conditions were similar for all strains, growth and compositional differences were ascribed to genetic factors. Significant differences were noted between strains in their muscle tissue for triacylglycerol (TG) levels, fatty acid composition, and tocopherol levels. The largest quantity of TG was found in the LSU strain whereas the smallest quantity was found in the AQUA strain. Levels of polyunsaturated fatty acids (PUFA) in the TG and total lipid (TL) fraction were highest in the AQUA strain and lowest in the MSU strain. Similarly, a peroxidizability index, which took into account the differences in susceptibility of unsaturated fatty acids to oxidize, was highest in AQUA and lowest in MSU for the TG and TL fractions. The peroxidizability index for the phospholipid fraction did not vary between strains. Adopting a relative antioxidant effectiveness value of 0.31 for γ‐tocopherol, the LSU, MSU and AQUA catfish strains were calculated to contain 37.72, 22.79 and 42.49 nmol of α‐tocopherol equivalents, respectively. The MSU catfish strain exhibited the highest ratio (nmol PUFA/nmol α‐tocopherol equivalents) suggesting that its tissue would be the least stable to oxidation.
Development of a method to measure rheological properties of carrot cell and cell‐wall materials
Authors: Ramana Sundara V. , Taylor Andrew J.
Published: October 2006

A method for measuring the rheological properties of carrot cells and cell‐wall material during typical cooking conditions has been evaluated. A Bohlin controlled‐stress rheometer with a rapid heating attachment was used. Because of potential slippage and sensitivity problems with cells and cell‐wall material, different geometries (parallel plate, cone and plate, and concentric cylinder) were assessed. Initial experiments were designed to determine the linear viscoelastic regions for the cell and cell‐wall materials at 25°C. Samples were subjected to varying shear stresses and oscillatory frequencies. For carrot cells, linearity was observed with cone and plate geometry and with concentric cylinder geometry over a fairly wide range of stresses and frequencies. Parallel plate geometry did not give linear results. Carrot cell‐wall material behaved in a linear fashion with all three geometries over similar stress and frequency ranges as carrot cells. Using the appropriate conditions of geometry, frequency and stress, the influence of heat treatments on cell and cell‐wall rheology was compared. A comparison of cone and plate and concentric cylinder geometry was performed using cells and cell‐wall material heated from 25 to 90°C. Cone and plate geometry showed greater changes in rheological properties during heating than concentric cylinder geometry and also allowed a greater range of heating rates. Cone and plate geometry was used in further studies. Studies on the rheological behaviour of cells during heating showed that the complex shear modulus (G*) increased in the range 25–75°C then decreased. For cell‐wall material, G* showed a steady increase from 25 to 90°C. Further experiments demonstrated that the increase in G* was not due to water loss during heating. The amount of cell damage during heating was measured using a conductivity meter to establish if there was a correlation between changes in G* and cell damage.
Relationship between softening and the polyuronides in ripening banana fruit
Authors: Wade Neil L. , Kavanagh Eve E. , Hockley Denis G. , Brady Colin J.
Published: October 2006

Banana fruits, Musa (AAA Group, Cavendish subgroup) ‘Williams’ were ripened in air at 20°C with ethylene. Pulp began softening between days 1 and 2 of ripening and reached a maximum by the fourth day. Total pulp cell wall uronic acid and uronic acid soluble in 40 mM EDTA, 50 mM acetate, pH 4.5, also began to decrease and increase respectively between days 1 and 2. By day 8, total uronic acid had decreased from 10.2 to 4.4 mg g−1 fresh weight, and had become entirely soluble in EDTA‐buffer, while EDTA‐buffer‐soluble uronic acid had increased from 2.3 to 4.5 mg g−1. The molecular size distribution of the EDTA‐buffer‐soluble uronic acid was unchanged up to day 4, when there was a slight loss in the proportion of smaller species. The average molecular size of this uronic acid did not change significantly during 8 days of ripening (relative to dextrans, Mn 36 kDa; Mw 173 kDa). The large change in total content and extractability of cell wall polyuronides that correlated with softening was inconsistent with depolymerisation by endopolygalacturonase (EC 3.2.1.15), reduced cross‐linking of polyuronides by calcium, or extraction artefacts.
The effect of nitric acid extraction variables on orange pectin
Authors: Aravantinos‐Zafiris G. , Oreopoulou V.
Published: October 2006

Pectin was extracted from dry orange waste with nitric acid. A factorial experimental design was used and the effects of temperature, time and pH of extraction on pectin yield and ‘jelly units’, ie pectin yield × viscosity of pectin solution were determined. Optimum conditions for pectin extraction are also discussed. According to ash and methoxyl content determinations the product can be classified as low ash and high methoxyl pectin. Its purity expressed as anhydrogalacturonic acid content varied from 68.5 to 75.0%.
Effect of lime on the dissolution of two phosphate rocks in acid soils
Authors: Hanafi Mohamed M. , Keith Syers J. , Bolan Nanthi S.
Published: October 2006

The effect of pH and calcium (Ca) on the dissolution of Gafsa (GPR) and Christmas Island A (CIPR) phosphate rocks (PR) was examined in closedincubation and open‐leaching systems in six acid, Malaysian soils. The pH of the soils was increased to between 4.5 and 6.1 by incubating with calcium carbonate (CaCO3); soil was also incubated with calcium chloride (CaCl2) to provide equivalent amounts of Ca without causing any marked change in pH. In the closed‐incubation system, dissolution of reactive GPR was overall higher (11–70%) than for the less reactive CIPR (12–43%) after 60 days of incubation. Dissolution of PR decreased with increasing levels of CaCO3or CaCl2, but the decrease was more pronounced in CaCO3‐treated than in CaCl2‐treated soils. Increasing additions of CaCl2decreased the size of the available sink for Ca from 84.0 to 0 mmol (+) kg–1soil. Although the addition of CaCO3increased the cation‐exchange capacity (CEC) of these variable‐charge soils (from 23.0 to 199.0 mmol (+) kg–1soil), most of the newly‐created exchange sites were occupied by Ca added through CaCO3. This was responsible for the decrease in size of the sink for Ca. Addition of CaCO3also decreased the proton supply from 260.7 to 0 mmol (+) kg–1soil, which in conjunction with the decrease in size of the Ca sink decreased the dissolution of PR. The effect of CaCO3and CaCl2on PR dissolution varied between soils and was related to pH‐buffering and the Ca‐sink size. In an open‐leaching system, large amounts of Ca (8–40%) added as CaCO3were removed in the leachate and hence the decrease in GPR dissolution with CaCO3addition was less in the open‐leaching than in the closed‐incubation system.
Contribution of gas chromatographic and conventional data to the characterisation of majorcan musts and wines by means of pattern recognition techniques
Authors: Forcén Marisa , Mulet Antonio , Berna Angel
Published: October 2006

Determination of the composition of three Majorcan red wines and musts (from zona Alta and zona Baja) was performed by gas chromatography. Previous data of the former samples derived from both conventional and capillary gas chromatographic analysis were added to the former physical and chemical data and then treated by two statistical methods of pattern recognition: multiple discriminant analysis (MDA) and hierarchical clustering analysis (CA), in order to re‐evaluate a characterisation study on wines and musts. A feature selection of the data by means of the F ratio value was carried out before the statistical techniques were applied. According to MDA, density, alcohol content, colour intensity, nitrogen and cis‐3‐hexen‐1‐ol were the major discriminating variables involved in the varietal classification of wines. Baume degree, colour intensity and proline were obtained in the corresponding musts. When distinguishing regions 2‐phenylethylacetate and glycerol were selected in wines, and pH and benzyl alcohol in musts. Musts and wines were mainly grouped according to the varietal characteristics of the samples by CA.
Effect of different solvents on protein recovery and neurotoxin and trypsin inhibitor contents of grass pea (Lathyrus sativus)
Authors: Deshpande Sudhir S. , Campbell Clayton G.
Published: October 2006

The efficiencies of several solvent systems for the solubilization of grass pea (Lathyrus sativus) proteins and for the removal of the neurotoxin, β‐N‐oxalylamino‐L‐alanine (BOAA) and trypsin inhibitor were investigated. On a seed protein basis, over 700 g kg−1 protein was recovered under alkaline conditions, 610 g kg−1 using isoelectric protein precipitation and about 500 g kg−1 in sulphate salts of sodium and potassium. Grass pea proteins were least soluble in the sodium acetate system. In contrast to the trypsin inhibitor that was concentrated in the protein isolates, BOAA levels decreased by about 50–85% depending on the extractant used. A characteristic SDS–PAGE profile of sodium‐acetate‐extracted proteins demonstrated their being soluble to a greater degree at pH 4–6, while the others showed a minimal protein solubility around pH 5.0.
Foaming capacity of fish minces during frozen storage
Authors: Huidobro Almudena , Tejada Margarita
Published: October 2006

This work covers a year's study of the foaming capacity (FC) of minced muscle of three fish species—blue whiting (Micromesistius poutassou R). horse mackerel (Trachurus trachurus L), and mackerel (Scomber scombrus L)—caught in two different seasons (January and July) and stored at – 18°C. Periodic assays were performed to determine protein solubility, FC and dimethylamine formation.

The results show that FC is initially inhibited by the presence of the species own lipids; however, during frozen storage this effect is attenuated and thus FC increases. The results corroborate the view that protein solubility is not an indispensible requisite for FC, and that mere dispersion of proteins is sufficient. However, FC is not diminished by changes in protein during frozen storage when this deficiency is offset by sufficient protein concentration. On the other hand, FC is clearly affected by the formaldehyde generated during frozen storage, so that beyond a certain level the aggregates formed as a result of formaldehyde formation are too large to disperse, and hence FC decreases drastically.
Proteins in developing sorghum endosperm that may be involved in resistance to grain moulds
Authors: Kumari Sunitha R. , Chandrashekar A. , Shetty H S
Published: October 2006

The level and type of fungal infection on grains varying in hardness at different stages of development over two seasons has been studied. Hard grains showed less incidence of grain moulds than soft grains during development. Microscopic examination showed more intense deposition of protein bodies in hard than in the soft grains. The presence of fungal hyphae in the endosperm of soft grains and pitted starch granules was clearly visible microscopically. Extracts of immature and mature hard and soft endosperm were inhibitory to Fusarium moniliforme growth. These inhibitors were heat labile and non‐dialysable indicating that protein factors may be involved. The activities of inhibitors to serine proteases were comparatively higher in endosperm of hard grains during development. The endosperm of hard grains contained more protein and prolamine than that of soft grains. A role for proteins in resistance of fungal infection in low tannin lines is presented.
Effect of temperature on the antioxidative action of inhibitors in lipid autoxidation
Authors: Marinova Emma M. , Yanishlieva Nedjalka V.
Published: October 2006

Purified lard triacylglycerols have been oxidised at 25, 50, 75 and 100°C in the presence and absence of 0.2–2.0 g kg−1 (0.45–10.3 mmol litre−1) of the antioxidants α‐tocopherol and ferulic acid. Increasing the temperature does not influence the effect of ferulic acid on the induction period or the rate of autoxidation, α‐tocopherol is more effective at extending the induction period and reducing the rate of autoxidation as the temperature is increased. The rate of substrate oxidation increases with increasing α‐tocopherol concentration, especially at lower temperatures, but decreases with increasing ferulic acid concentration. This behaviour is explained in terms of the participation of antioxidant molecules and radicals in the autoxidation process. High‐temperature oxidation results can be extrapolated only to room temperature when no change occurs in the antioxidative mechanism.
Analysis of lignin from oak casks used for the maturation of Scotch whisky
Authors: Conner John M. , Paterson Alistair , Piggott John R.
Published: October 2006

Wood from four types of casks used for the maturation of Scotch whisky was analysed for free vanillin, syringaldehyde, vanillic and syringic acids and for milled wood lignin. Degradation of wood lignin by acidolysis was used to estimate the proportion of intact β‐aryl ether linkages present. The yield of milled wood lignin was unaffected by repeated cask use. A comparison of acidolysis yields and the analysis of spirit matured for 3 years in each of the four types of cask indicated that the majority of β‐aryl ether linkages in oak lignin are resistant to spirit hydrolysis and that cask exhaustion was not accompanied by significant delignification. Significant reductions in the concentrations of free guaiacyl and syringyl compounds were recorded for used casks and proved the best indicator of cask exhaustion.
Effects of methionine addition in soya bean or casein diets supplemented with carrageenan on weight gain and blood lipids in rats
Authors: Mouécoucou Justine , Villaume Christian , Bau Hwei‐Ming , Nicolas Jean‐Pierre , Méjean Luc
Published: October 2006

Seven groups of 12 Wistar rats were fed during two experimental periods. During the first period of 4 weeks, rats were fed diets containing 100 g kg−1 of casein or soya‐protein. In the case of casein, diets contained casein, casein + 3.5 g kg−1 of sodium carrageenan and casein + 3.5 g kg−1 of sodium carrageenan + 1 g kg−1 of DL‐methionine. In the case of soya protein, diets contained soya protein, soya protein + 6.2 g kg−1 of sodium carrageenan, soya protein + 6.2 g kg−1 of sodium carrageenan + 1 g kg−1 of DL‐methionine and soya protein + 1 g kg−1 of DL‐methionine. During the second period of 8 weeks, all rats were fed laboratory pellets containing 170 g kg−1 of standard protein mixture. Methionine supplementation of heated soya bean meal containing carrageenan prevented the decrease of growth observed with unsupplemented diet. Methionine supplementation of casein improved protein efficiency ratio and had no effect on long‐term growth of rats because carrageenan did not cause growth retardation. At the end of second period, carrageenan ingested during the first period had no effect on plasma cholesterol. When carrageenans added to casein were ingested during the first period, plasma triglycerides were significantly lower after the second period. It would seem that carrageenans induce protein malnutrition by a lack of methionine when they are present in low protein diets with low methionine content, and that a sufficient content of methionine in diets prevents the carrageenan effect.
Study of factors affecting the absorption of aroma compounds into low‐density polyethylene
Authors: Nielsen Tim J. , Margaretha Jägerstad I. , Öste Rickard E.
Published: October 2006

A supercritical fluid extraction/gas chromatography method has been used to study the influence of different factors on the absorption of aroma compounds into low‐density polyethylene. Factors studied included concentration of aroma substances, storage temperature, pH and interactive effects of different food components. There were no significant differences in the partition coefficients when the concentration of the flavours was varied between 0.1 and 10 mg kg−1. The storage temperature, however, affected the absorption significantly (P < 0.05), approximately twice as much was absorbed at 75°C compared with 5°C. Acidification to pH 3 with acetic acid did not significantly alter the amounts of the aromas being absorbed. Further, when occurring alone in the model solutions the aroma substances had much larger partition coefficients than when in mixtures with others, indicating an antagonistic effect of different aroma compounds on absorption. Olive oil and, thereby, the flavours dissolved in the oil, were absorbed in large amounts by the plastic. Extractions of plastic films stored in concentrated apple juice were successfully carried out. In addition to many unknown substances, nine of the 10 aromas used in the model solution were detected in the plastic stored in concentrated apple juice.
Germination alters the chemical composition and protein quality of lupin seeds
Authors: Dagnia Suzanne G. , Petterson David S. , Bell Roma R. , Flanagan Frank V.
Published: October 2006

The chemical composition and protein quality of the kernels from Lupinus angustifolius seeds were compared with that for sprouts after 6 days germination. Germination resulted in an apparent increase in protein content from 395 g kg−1 to 435 g kg−1 DM. Fat and carbohydrate contents decreased. The oligosaccharide content of the sprouted lupin fell to a negligible level, while the phytate and alkaloid concentrations fell from 4.7 g kg−1 to 1.6 g kg−1 and from 0.72 g kg−1 to 0.16 g kg−1, respectively.

The quality of lupin kernel protein was poor with a protein efficiency ratio (PER) of 1.45±0.15. Supplementation of kernel with DL‐methionine (2.0 g kg−1) increased the protein quality (PER = 2.87±0.17) to that of casein (PER = 2.86±0.18). Germination reduced protein quality (PER = 0.44±0.16), and did not improve apparent protein digestibility (APD kernel = 80.4%; APD sprout = 77.5%). Supplementation of sprout protein with DL‐methionine (2.0 g kg−1) increased the protein quality (PER = 2.57±0.20). The total sulphur‐containing amino acid concentration of lupin kernel protein, 1.9 g per 16 g N was low, and decreased further to 1.3 g per 16 g N in the sprout, a drop of 32%.

The results showed that germination of lupin seeds reduced the concentration of the anti‐nutritive factors; however, it also reduced protein quality.
Ft‐ir spectroscopy as a tool for the study of biological and chemical treatments of barley straw
Authors: Stewart D. , Morrison I M
Published: October 2006

Diffuse reflectance Fourier transform infrared (FT‐IR) spectroscopy has been used to characterise the changes in barley straw when subjected to biological and chemical treatments. The untreated and treated straws were also analysed by traditional analytical techniques for neutral sugar residues and lignin. A comparison between the spectroscopic data and the chemical analyses showed that FT‐IR spectroscopy was a quick and non‐destructive analytical technique which could be used to assess the efficacy of treatments applied to annual plants.
Studies on the bacterial acidification process of cassava (Manihot esculenta)
Authors: Meraz Mónica , Shirai Keiko , Larralde Patrcia , Revah Sergio
Published: October 2006

Different types of inocula for cassava were compared in the Gari type fermentation of cassava. High acidification rates were achieved with Lactobacillus plantarum, Lactobacillus cellobiosus and with re‐inoculation from the liquid drained from a previous batch. Slower rates were obtained inoculating from a previously fermented batch and with the natural acidification process. Serial fermentations made re‐inoculating from a previous batch increased the acidification rates and established a population of Lactococcus, Leuconostoc and Pediococcus.
Purification and properties of polyphenol oxidase from oil bean (Pentaclethra macrophylla Benth) seeds
Authors: Chilaka Ferdinand C , Anosike Emmanuel O , Egbuna Patrick C
Published: October 2006

Polyphenol oxidase extracted from oil bean (Pentaclethra macrophylla) seeds was purified 165‐fold over the crude enzyme extract. The apparent molecular weight of the enzyme by gel filtration was 110.8 k ± 9.0 k while SDS‐PAGE indicated a single species of molecular weight 28.0 k. A copper content of 1.9 mg g−1 corresponds to one copper atom for each of the four subunits. The purified enzyme oxidised pyrogallol, catechol, 4‐methylcatechol and L‐dihydroxyphenylalanine but had low activity towards tyrosine. p‐Cresol, caffeic acid and cholorogenic acid were not oxidised. Thio‐compounds were strong inhibitors of the enzyme. The phenolic compounds tyrosine, resorcinol and orcinol inhibited catechol oxidation but became oxidised in the process.
Cassava leaves as animal feed: Potential and limitations
Authors: Ravindran Velmurugu
Published: October 2006

The nutrient composition and potential productivity of cassava (Manihot esculenta Crantz) leaves are examined, and their usefulness as a protein supplement in animal nutrition in the tropics is reviewed. On average, meal prepared from cassava leaves contains (on a dry matter basis) 210 g kg−1 crude protein, 250 g kg−1 acid detergent fibre, 85 g kg−1 ash, 14.5 g kg−1 calcium and 4.5 g kg−1 phosphorus. Cassava leaf protein is well balanced, except for a deficiency of sulphur‐containing amino acids. The presence of hydrocyanic acid and tannins is considered, but a leaf meal with low levels of these anti‐nutritional factors may be prepared using simple processing techniques. The most immediate prospects for the use of cassava leaf products are in the following areas: (i) low level inclusion of leaf meal in feed formulations for monogastric animals, and (ii) fresh forage as a protein supplement to low‐quality roughages in ruminant feeding. Relevant future research needs are also identified.
Variation in type and relative amounts of the high molecular weight glutenin subunits in dutch wheat varieties
Authors: Kolster Peter , Krechting Kees F , Van Gelder Wim M J
Published: October 2006

The high molecular weight glutenin (HMWg) subunit genotypes and amounts of the individual subunits of 38 Dutch wheat varieties were determined. In winter wheat varieties, HMWg subunit alleles that, in general, have been shown to be related to a poor bread‐making quality predominated. In spring wheat varieties, ‘high‐quality’ alleles were most frequent. When examining the published HMWg subunit genotypes of British and German varieties a similar difference was found in HMWg subunit genotype between spring and winter wheats. Because bread‐making quality of spring wheat varieties is, in general, superior to that of winter wheats, probably also because of the lower protein content of the latter, the two groups should be taken separately when studying the relation between HMWg subunit genotype and bread‐making quality. There was a considerable variation in relative amounts of allelic HMWg subunits and of subunits encoded by different genes (at the same or homeologous loci). Between varieties with the same HMWg subunit genotype, relative amounts of identical subunits differed only slightly. Some of these differences may reflect differences in gene expression, but it is not known to what extent differences in genetic background or differences in gene promoter are involved. There were differences in relative amounts of HMWg subunits encoded by alleles at the Glu‐Bl locus. Here, an increase in relative amounts coincided with an increase in contribution to bread‐making quality of an allele.