bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterisation of residual fibres from fermentation of pea and apple fibres by human faecal bacteria
Authors: Guillon Fabienne , Renard Catherine M G C , Hospers Jeannette , Thibault Jean‐Francois , Barry Jean‐Luc 
Published: November 2006

AbstractTwo dietary fibres with distinct structural features (pea hull and apple fibre) were fermented in vitro with human faecal bacteria. The composition and physicochemical properties (cation exchange, hydration properties) of the residues were examined. Gas and short‐chain fatty acid (SFCA) productions attested of the highest fermentability of apple fibre. After 24 h, 75% of the pea fibre and 42% of the apple fibre could be recovered. Production of the major SCFA, acetate, propionate and butyrate occured in the molar ratio 68:17:9 for both fibres. Uronic acid and arabinose were the most extensively fermented sugars while xylose and glucose were the least fermented. Cation exchange capacity of the two fibres did not decrease much during fermentation, which implies that the amount of bound mineral is proportional to the amount of residual fibres. The values of the hydration properties of the residual fibres were at least equal to or higher than those of initial fibres. In spite of the degradation of the fibres during fermentation, a physical structure able to retain water remained.
Disappearance of chlorophylls and carotenoids during the ripening of the olive
Authors: Mínguez‐Mosquera Isabel , Gallardo‐Guerrero Lourdes 
Published: November 2006

AbstractAlthough the colour of olives changes from green to yellow, turning colour, purple and black according to the stage of ripeness, chlorophyll a is always the major chloroplastic pigment followed by chlorophyll b. Carotenoids are also present as minor components. Among these, lutein and β‐carotene are worthy of mention, while neoxanthin, violaxanthin and antheraxanthin are present in lower proportions. The concentration of the chlorophylls and the carotenoids decreases gradually as harvesting approaches. When the colour of the fruit is predominantly green, the percentage decrease of the carotenoid fraction is higher than that experienced by the chlorophyll fraction. In the latter fraction at this stage chlorophyll b is preferentially degraded. In contrast, in the yellow colour stage, the disappearance of chlorophylls is noticeably higher than that of carotenoids, the levels of which tend to be maintained with minimal pigment degradation at this stage. This faster degradation of the chlorophylls allows the coloration due to the carotenoids to be seen in the fruit. From this moment onwards, once the stage of ripening has begun, the rate of degradation of the chlorophyll fraction increases to almost twice that of the carotenoid fraction, and chlorophyll a disappears faster than chlorophyll b. The ratio of lutein to β‐carotene decreases as ripening advances reflecting the higher rate of degradation of lutein.
Physical properties of cold‐setting gels formed from heat‐denatured whey protein isolate
Authors: McClements D Julian , Keogh M Kieran 
Published: November 2006

AbstractCold‐setting gels were formed from a 100 g kg−1 whey protein isolate (WPI) solution (pH 7.0) which had been heated to 90°C for 30 min in the absence of salt. Heating caused the globular protein molecules to unfold and form linear aggregates, but electrostatic repulsion opposed extensive protein‐protein interactions and so prevented gel formation. When the solution containing heat‐denatured proteins was cooled to room temperature and mixed with NaCl (0.2 mol kg−1), the electrostatic charges were shielded and a gel formed. The rate of gel formation increased on cooling, which suggests that the major driving force for protein aggregation and gelation is the hydrophobic effect. Once formed, the rigidity of the gels decreased with decreasing temperature, which suggested that non‐hydrophobic forces (eg configurational entropy, hydrogen bonding, van der Waals forces and disulphide bond formation) are more important in determining the final gel rigidity. The turbidity and rigidity of gels formed by adding salt to preheated WPI at room temperature were less than those of gels formed by heating WPI in the presence of salt. The ability of WPI to form cold‐setting gels with relatively low turbidity extends the range of applications of whey proteins as functional ingredients in the food industry.
Cryoprotectants improve physical and chemical properties of frozen blue crab meat (Callinectes sapidus)
Authors: Henry L K , Boyd L C , Green D P 
Published: November 2006

AbstractThe storage stability of cryogenically frozen crab meat treated with cryoprotectants was compared with pasteurised and water‐treated frozen samples to determine changes in physical and chemical properties. Commercially processed, hand‐picked blue crab meat was treated with solutions of polydextrose, sucrose + sorbitol/sodium tripolyphosphate or water, vacuum packaged, and cryogenically frozen prior to storage at −29°C. All treatments were compared with an untreated reference control stored at −65°C and a pasteurised sample stored at 1.1°C. Samples were evaluated for physical and chemical changes at 4‐week intervals over 32 weeks of storage. Cryoprotectants improved oxidative stability, drip loss, expressible moisture, texture, and colour compared to untreated reference and pasteurised samples.
Chemical composition of olive by‐product and modifications through enzymatic treatments
Authors: Valiente Cruces , Arrigoni Eva , Esteban Rosa M , Amadò Renato 
Published: November 2006

AbstractThe purpose of the present work was to study the dietary fibre (DF) fraction of olive cake and modify the fibre structure through enzymatic treatments in order to improve the sensory quality of this by‐product for its incorporation into a baked product. Two different commercial enzyme preparations were used for enzymatic modifications: Viscozyme L, a hemecellulase/cellulase multi‐enzyme complex, and Olivex which contains different pectolitic main activities as well as various side activities, hemicellulases and cellulases. DF consists of 800 g total dietary fibre per kg dry matter. More than 91% of the DF are insoluble and the monosaccharide composition of this fraction indicates the presence of mainly cellulose and xyloglucans or xylans. Approximately 75% of the uronic acids found in olive cake are associated to the insoluble DF (IDF). Arabinans and uronic acids polysaccharides are the major fibre components in the soluble DF (SDF) fraction. Enzymatic treatments with commercial preparations caused changes in the DF content and in the IDF:SDF ratio depending on enzyme concentrations and incubation time. Baking experiments showed that a substitution of 10% of wheat flour by enzymatically modified olive cake led to an improved texture compared to products containing untreated cake.
The 15N‐isotope dilution method for determining ileal endogenous nitrogen excretion in the young (10 kg liveweight) pig
Authors: Schulze Hagen , Butts Christine A , Moughan Paul J , Verstegen Martin W A 
Published: November 2006

AbstractA study was conducted with four crossbred 5‐week‐old castrated male pigs at an average body weight of 10 kg to determine the endogenous amino acid and nitrogen flows at the terminal ileum using the peptide alimentation and 15N‐isotope dilution methods. The pigs were fitted with a post‐valvular T caecal cannula and two indwelling blood catheters. They were fed a cornstarch‐based semisyn'hetic diet formulated to contain enzymically hydrolysed casein (EHC) as the sole source of nitrogen at twice their maintenance requirement for energy. Digesta were centrifuged and ultrafiltrated after collection and the precipitate plus retentate fraction (mol wt > 10000) was used to determine the endogenous amino acid and nitrogen flows. To estimate the endogenous N flow at the terminal ileum of these EHC‐fed pigs using the 15N‐isotope dilution method a constant 10 day 15N‐leucine infusion was performed at a daily rate of 5‐04 mg of 15N‐leucine (95% 15N enrichment) kg−1 body weight. The mean 15N‐enrichments above background for the trichloroacetic acid soluble blood plasma and ileal digesta nitrogen pools were 0.0249 and 0.0178, respectively. There were no statistically significant differences for 15N‐enrichment excess between the days of ileal digesta collection. The results demonstrated that glutamic acid, aspartic acid, proline and serine formed about 50% of the total ileal endogenous amino acid flow. The total daily amount of endogenous amino acid flow at the terminal ileum was 6.2 g day−1. The endogenous ileal N flows determined with the peptide alimentation and the 15N‐isotope dilution methods were similar (P = 0.40) at 1.37 and 1.17 g day−1, respectively. Endogenous N as a proportion of total N flow passing the terminal ileum was 83% and 72% for the peptide alimentation and the 15N‐isotope dilution method, respectively. The study provides some support for application of the 15N‐isotope dilution method with pigs.
Studies on the enzymatic hydrolysis of Brazilian lobster (Panulirus spp) processing wastes
Authors: Vieira Gustavo H F , Martin Antonio M , Saker‐Sampaiao Silvana , Omar Semir , Goncalves Raimunda C F 
Published: November 2006

AbstractMeat recovered from the cephalothorax of the lobster (Panulirus spp), which is normally discarded during processing, was subjected to hydrolysis. The enzymes used were papain, pepsin and a fungal protease, each one tested at concentrations of 2, 4 and 5 mg g−1 (enzyme/substrate, wet weight basis). The degree of hydrolysis, measured by the release of tyrosine, was found to be highest when fungal protease was used, followed by papain and pepsin. Of the concentrations tested, it was found that 5 mg g−1 produced the highest degree of hydrolysis in the three enzymes. The protein hydrolysates produced were highly soluble, with excellent wettability and some capacity for oil emulsification. No bitter off‐flavour was detected in the final product.
Solid‐state fermentation of Lathyrus sativus seeds using Aspergillus oryzae and Rhizopus oligosporus sp T‐3 to eliminate the neurotoxin β‐ODAP without loss of nutritional value
Authors: Kuo Yu‐Haey , Bau Hwei‐Ming , Quemener Bernard , Khan Jehangir K , Lambein Fernand 
Published: November 2006

AbstractThe presence of a neurotoxic amino acid, 3‐N‐oxalyl‐L‐2,3‐diaminopropanoic acid (β‐ODAP), in the seeds of grass pea (Lathyrus sativus) is the cause of an irreversible spastic paraparesis, neurolathyrism, after over‐consumption. This is a negative factor in an otherwise very tasty, nutritious, easily cultivated and hardy food crop in Asia and Africa. The reduction of β‐ODAP to less than 10% of the original content has been reached by fermenting L sativas Jamalpur seeds with Aspergillus oryzae NRRL 1988 for 48 h, followed by fermentation with Rhizopus oligosporus sp T‐3 for 48 h. Other nutritional qualities were also improved in the fermented seed meal: increased content of protein, higher amino acid scores for sulphur‐containing and aromatic amino acids, better resistance to high temperature and to oxidation, and drastic reduction of the flatulence factors.
Non‐destructive determination of fat, moisture and protein in salmon fillets by use of near‐infrared diffuse spectroscopy
Authors: Isaksson Tomas , Tøgersen Geir , Iversen Arve , Hildrum Kjell Ivar 
Published: November 2006

AbstractNear infrared (NIR) diffuse spectroscopy was used to determine the fat, moisture and protein contents in whole and ground farmed atlantic salmon fillets. A remote fibre‐optic probe was used for NIR measurements on 50 whole salmon fillets. The constituent ranges were: 91‐205 g kg−1 fat, 599‐709g kg−1 moisture and 186‐209 g kg−1 protein. Principal component regression resulted in the following prediction errors for ground salmon fillets, expressed as root mean square error of cross validation: 6.6 g kg‐1 fat, 3.8 g kg−1 moisture and 2.0 g kg−1 protein. The corresponding prediction errors for non‐destructive measurements on whole salmon fillets were 10.8 g kg−1 fat, 8.5 g kg−1 moisture and 3.7 g kg−1 protein. Regression models using the 760‐1100 m range gave lower prediction errors than models using the 1100‐2500 mm or 760‐2500 nm ranges. The results show that fibre‐optic probe NIR instruments are suited to determine fat and moisture in whole salmon fillets non‐destructively.
Production of raw starch digesting amylase by Aspergillus niger grown on native starch sources
Authors: Okolo Bartholomew N , Ezeogu Lewis I , Mba Charles N 
Published: November 2006

AbstractAspergillus niger isolated from rotting cassava produced raw starch degrading amylase on cassava, maize, sorghum and soluble potato‐derived starch as the sole carbon source without prior gelatinisation. Maximum activity of the amylase was attaired using cassava starch as substrate. The crude enzyme solution which comprised a mixture of raw and non raw starch digesting amylase degraded both cereal and tuber or root starches significantly. Source of assay starch significantly influenced raw starch digesting activity. Optimum pH for the raw starch degrading and the extracellular amylase were 6.0 and 3.5‐4.0, respectively. However, both enzyme activities appeared to be uninfluenced across a relatively broad pH range 3.0‐7.0. No correlation was found between the capacity of starch to induce expression of the enzyme and its susceptibility to enzyme digestion. The adsorbability of the various starches to raw starch digesting amylase was directly related to their digestibility.
Determination of lignin in the presence of ester‐bound substituted cinnamic acids by a modified acetyl bromide procedure
Authors: Morrison Ian M , Stewart Derek 
Published: November 2006

AbstractThe lignin content of plant materials can be determined spectro‐scopically but the presence of ester‐bound substituted cinnamic acids in the cell walls of some plant families, particularly the Gramineae, gives elevated values. Pre‐treatment with either pyrrolidine : pyridine or 0‐5 m sodium methoxide selectively removes the ester‐bound acids leaving intact the true lignin. The treatments have been applied to cellulose powder, immature perennial ryegrass stems, oat straw and forage rape stems. The pyrrolidine : pyridine treatment removes a slightly higher proportion of these non‐lignin components but the sodium methoxide treatment appears to cause less damage than the heterocyclic bases to other cell wall constituents and is preferred if the residues are to be used for other purposes.
Total lipids content and fatty acid composition of seed oils from six pomegranate cultivars
Authors: Melgarejo P , Salazar D M , Amorós A , Artés F 
Published: November 2006

AbstractThe fatty acid composition of the seed oils of six pomegranate (Punica granatum L) cultivars was qualitatively and quantitatively determined by gas chromatography. The seeds contained oil in the range 51‐152 mg kg−1 dry matter. Intervarietal differences in fatty acid composition were demonstrated (fatty acid esters as % (w/w) total fatty acid esters. Sour varieties had the highest while sour‐sweet varieties had the lowest oil content. Eleven fatty acids were identified. In all varieties, the predominant fatty acids were linoleic (25.2‐38.6%) and oleic acid (24.8‐35.5%) followed by palmitic (18.2‐22.6%), stearic (6.9‐10.4%) and linolenic acid (0.6‐9.9%). To a lesser extent arachidic (1.1‐3.4%) and palmitoleic acid (0.2‐2.7%) were also found in all varieties. Lauric, myristic, behenic and lignoceric acids were rarely detected. As far as we know linolenic (18:3), arachidic (20:0), behenic (22:0) or lignoceric (24:0) acids have not been previously reported in the seed oils of edible pomegranate varieties. Lignoceric acid has not previously been found in pomegranate seed oil.
Effect of γ‐irradiation on enzymatic digestion of oil palm empty fruit bunch
Authors: Matsuhashi Shinpei , Kume Tamikazu , Hashimoto Shoji , Awang Mat R 
Published: November 2006

AbstractEffect of γ‐irradiation and combination treatment with alkali on oil palm empty fruit bunch (EFB) was studied to enhance the efficiency of enzymatic digestibility. γ‐Irradiation enhanced the enzymatic digestibility, and the amounts of released galacturonic acid and neutral sugars from EFB by Driselase were increased with an increase in irradiation dose. The main components of neutral sugars released from EFB were glucose and xylose. EFB treated with alkali and 50 kGy irradiation released 1200 μg g−1 of xylose that was twice amount of glucose showing that the combination treatment was effective especially to increase the digestibility of xylan.
Factors affecting in vitro formation of tannin‐protein complexes
Authors: Perez‐Maldonado Rider A , Norton Barry W , Kerven Graham L 
Published: November 2006

AbstractIn interaction of condensed tannins from Desmodium intortum and Lotus pedunculatus and tannic acid (hydrolysable tannin) with salivary mucoproteins (from sheep and goats), plant leaf proteins and bovine serum albumin were evaluated. These studies were carried out over a pH range of 2‐0‐9‐0 and different inorganic ion conditions to simulate conditions in which dietary proteins would interact with tannins in a ruminant digestive tract. Insoluble tannin‐protein interactions were found at pH 4–5–5–5 for bovine serum albumin and 3–5–5–5 for plant leaf protein. The present study showed that pH alone was not the sole determinant for tannin‐protein complex formation, since tannin‐protein complexation was found in the pH range 6‐0–6‐5 when different inorganic ions were added to the solutions. Insoluble complexes were not formed with salivary proteins, although precipitation by tannic acid was achieved at 5°C. This suggests that tannins may form soluble rather than insoluble complexes with salivary proteins. It was concluded that purified F1 leaf protein (the major protei occurring in leaf tissue) ought to be used as the test protein for evaluating tannin‐protein interactions for in vitro assay procedures. Using this method it was calculated that 27–43% and 19–40% of available plant protein may interact with condensed tannins from Desmodium intortum and Lotus pedunculatus, respectively.
High‐performance liquid chromatography determination of proline isomers in Italian wines
Authors: Calabrese Massimo , Stancher Bruno , Riccobon Patrizia 
Published: November 2006

AbstractThis paper deals with the quantitative reverse‐phase high‐performance liquid chromatography (RP‐HPLC) analysis of the isomers of proline, the most abundant amino acid in wine, and with the relative isomeric presence in samples of different vintage and geographical origin. The sample preparation was carried out by using Marfey's reagent ((‐fluoro‐2,4‐dinitrophenyl)‐5‐L‐alanine amide (FDAA)) for the derivatisation reaction in order to obtain dl and ll diastereomers of the corresponding optically active amino acids. The separation was performed with an analytical column for RP‐HPLC Nucleosil 100‐5 C18 (25 × 0.4 cm id), adopting both isocratic and gradient procedures and making use of water/acetonitrile buffers as the mobile phase. It has been observed that the best resolution is achieved under gradient conditions, although the analysis takes a long time. L‐Norleucine was used as the internal standard for quantitative determination and the detection of components was made at the fixed wavelength of 340 nm. Peak identifications were performed by comparing retention times and observing on‐line UV spectra. Under these conditions the detection limit for proline isomers reached the value of 0–5 mg liter−1. Wine samples of different ages were analysed and it is possible to see that L‐proline is present only in ‘young’ wines, while the D‐isomer appears in wines that are at least 5 years old. The most abundant D‐proline content was observed in a 30 years vintage red wine of Puglie (southern Italy) with about 15% of the ratio D to D + L.
Unilateral non‐linear dynamic contact of thin‐walled structures using a primal‐dual active set strategy
Authors: Hartmann S. , Brunssen S. , Ramm E. , Wohlmuth B. 
Published: November 2006

AbstractThe efficient modelling of three‐dimensional contact problems is still a challenge in non‐linear implicit structural analysis. We use a primal‐dual active set strategy (SIAM J. Optim. 2003; 13:865–888), based on dual Lagrange multipliers (SIAM J. Numer. Anal. 2000; 38:989–1012) to handle the non‐linearity of the contact conditions. This allows us to enforce the contact constraints in a weak, integral sense without any additional parameter. Due to the biorthogonality condition of the basis functions, the Lagrange multipliers can be locally eliminated. We perform a static condensation to achieve a reduced system for the displacements. The Lagrange multipliers, representing the contact pressure, can be easily recovered from the displacements in a variationally consistent way.For the application to thin‐walled structures we adapt a three‐dimensional non‐linear shell formulation including the thickness stretch of the shell to contact problems. A reparametrization of the geometric description of the shell body gives us a surface‐oriented shell element, which allows the application of contact conditions directly to nodes lying on the contact surface. Shell typical locking phenomena are treated with the enhanced‐assumed‐strain‐method and the assumed‐natural‐strain‐method.The discretization in time is done with the implicit Generalized‐α method (J. Appl. Mech. 1993; 60:371–375) and the Generalized Energy–Momentum Method (Comp. Methods Appl. Mech. Eng. 1999; 178:343–366) to compare the development of energies within a frictionless contact description.In order to conserve the total energy within the discretized frictionless contact framework, we follow an approach from Laursen and Love (Int. J. Numer. Methods Eng. 2002; 53:245–274), who introduced a discrete contact velocity to update the velocity field in a post‐processing step.Various examples show the good performance of the primal‐dual active set strategy applied to the implicit dynamic analysis of thin‐walled structures. Copyright © 2006 John Wiley & Sons, Ltd.
Reactivity of hydroxynaphthalenes towards peroxyl radicals
Authors: Pino E. , Aspée A. , López‐Alarcón C. , Lissi E. 
Published: November 2006

AbstractIn the present work we report data bearing on the reaction of mono‐ and dihydroxynaphthalenes towards 2,2′‐azo‐bis(2‐amidinopropane) dihydrochloride (AAPH) derived peroxyl radicals. A comparison of the bleaching rates allows establishing their relative reactivity towards peroxyl radicals: 1,2‐dihydroxynaphthalene (1,2‐DHN) ≫ 2,3‐dihydroxynaphthalene (2,3‐DHN) > 1,3‐dihydroxynaphthalene (1,3‐DHN) ≥ 2,7‐dihydroxynaphthalene (2,7‐DHN) > 1‐hydroxynaphthalene (1‐N) ≥ 2‐hydroxynaphthalene (2‐N). Bleaching rates measured under conditions of quantitative trapping of peroxyl radicals allow an estimation of the number of molecules consumed per each radical introduced into the system. The results obtained imply a chain consumption of 1,2‐DHN and 2,3‐DHN. In fact, a fast autoxidation of 1,2‐DHN is observed even in absence of AAPH. The high reactivity of this compound suggests a fast hydrogen abstraction, due to its low OH bond dissociation energy (BDE), and/or a very fast electron transfer from the deprotonated form. Oxygen radical absorbance capacity (ORAC) indexes of the naphthalene derivatives were evaluated from their effect upon the peroxyl radical promoted bleaching of c‐phycocyanin (c‐Pc). ORAC values are strongly influenced by the secondary reactions of the additive and do not correlate with the reactivity of the compound or the number of the naphthalene derivative molecules bleached per each radical. c‐Pc bleaching rate in presence of an excess of hydroxyl‐naphthalene derivative was taken as a measure of the damaging capacity of the corresponding naphthoxyl radicals. The results indicate that this damaging capacity is inversely proportional to the reactivity of the parent compound. In fact, addition of 2‐naphthol, the less reactive of the tested compounds, increases the rate of c‐Pc bleaching promoted by peroxyl radicals. Copyright © 2006 John Wiley & Sons, Ltd.