bluuebunny/crossref_metadata_2025_split huggingface dataset:
Die Bedeutung von Sterilisationswerten für das Ultrahocherhitzen von Milch
Authors: Biewendt H.‐G. 
Published: November 2006

AbstractSeit Anfang der 20er Jahre wird der Sterilisationswert F0 (F‐Wert), der sich auf die Abtötung von Clostridium botulinum‐Sporen bezieht, herangezogen, um die mikrobiologische Wirksamkeit von Sterilisationsverfahren zur überprüfen. 1980 wurden erstmals milchspezifische F‐Werte zur Beurteilung von UHT‐Verfahren auf der Grundlage hitzebedingter chemischer Veränderungen von Milchinhaltsstoffen vorgestellt. Zur F‐Wert‐Berechnung können alle Inhaltsstoffe herangezogen werden, die im halblogarithmischen Zeit‐Temperatur‐Diagramm ein lineares Abbau‐ bzw. Bildungsverhalten aufweisen. Systematische Untersuchungen haben gezeigt, daß dies für zahlreiche Milchinhaltsstoffe zutrifft. Da die Abtötungskurven der Mikroorganismen erheblich steiler verlaufen als die Kurven für chemische Reaktionen von Inhaltsstoffen, können UHT‐Verfahren hinsichtlich ausreichender Keimabtötung bei geringstmöglicher Produktbeeinträchtigung optimiert werden.Die wesentlichen Grundlagen zur Berechnung von Sterilisationswerten sowie zur Ermittlung mikrobiologischer und chemischer Reaktionen werden vorgestellt.
Changes in oil and potato chips during frying
Authors: Hebash K. A. , Fadel H. H. M. 
Published: November 2006

AbstractThe effect of frying of potato chips (batch processing during 12 h) on the chemical characteristics and fatty acid composition of the used oil were determined. Samples of the fried oil and potato chips were taken at various time periods. The volatile carbonyl compounds of the aroma concentrate of each sample were isolated and their oxime derevatives were prepared and subsequently estimated by UV absorption for the total oximes and conjugated diene carbonyl oximes. The development of the volatile carbonyl compounds in both frying oil and fried potato chips was increased on continued frying. Concerning the frying oil this increase was found to be in coincident with the decrease in the linoleic and linolenic acid percent.
Chromatographic separation of flaxseed phenolics
Authors: Amarowicz R. , Wanasundara P. K. J. P. D. , Shahidi F. 
Published: November 2006

AbstractA column chromatography method for separation of phenolic compounds from flaxseed using Sephadex LH‐20, RP‐8 and silica gel is described. TLC analysis proved that separated fractions contained numerous phenolic compounds. All fractions exhibited a maximum UV absorption between 270 and 290 nm. Additional shoulders were observed between 274 and 350 nm. These results imply that lignans and their derivatives are the main phenolic compounds present in flaxseed.
Comparison of processing treatments on the composition and functional properties of rapeseed preparations (Brassica campestris L. var. toria)
Authors: Mahajan A. , Dua S. 
Published: November 2006

AbstractRapeseed preparations viz. rapeseed meal, concentrates and isolates were prepared using different processing treatments involving organic solvents, acids, alkali, steaming and boiling. Their antinutritional constituents and functional properties were studied in comparison to undefatted meal. Percent decrease in phytic acid and phenolic content was maximum in seeds boiled for 30 min and isolates, respectively. Isolate II prepared by sodium hexa‐metaphosphate had minimum glucosinolates, maximum content of total proteins and much improved nitrogen solubility, emulsifying and foaming properties. Water absorption and fat absorption capacities were enhanced by boiling seeds prior to grinding and ammonia‐methanol extraction, respectively. Viscosity decreased in all the treatments as compared to control.
Rapeseed meal‐Glucosinolates and their antinutritional effects Part 6. Taint in end‐products
Authors: Mawson R. , Heaney R. K. , Zdunczyk Z. , Kozlowska H. 
Published: November 2006

AbstractFrom the present review it is clear that glucosinolates and their breakdown products may pass in small amounts into such products as meat, milk or eggs without noticeable deterioration in their taste. When applying low glucosinolate rapeseed meal (LG‐RSM) as the sole high protein component of concentrate mixture for cows, the level of rapeseed glucosinolates breakdown products should not exceed 0.1 μmol/1 oxazolidinethione, 10 μmol/1 unsaturated nitriles and 100 μmol/1 thiocyanate. At these levels no evidence has been found to indicate the negative influence of glucosinolates breakdown products on the sensory properties of milk or threat for consumers.No published information appears to be available suggesting that glucosinolates have any deleterious effect on the carcass flavour in cattle. Even at a 20% inclusion of LG‐RSM in diets no impairment on visual scores or sensory evaluation was found in pig's or broiler's carcass.Glucosinolated, chiefly progoitrin, which depress trimethylamine oxidation thus clearly affect the taint in eggs. In birds with genetically conditioned susceptibility (brown layers) fishy taint can be observed even at 0.3 μM progoitrin, i.e. approximately 0.5 μM total glucosinolates in 1 g diet. Assuming a threefold higher threshold for white layers (1 μM progoitrin in 1 g diet) fishy taint can be expected at a 10% LG‐RSM level in diet, and only very low glucosinolate rapeseed meals can be fed to layers without the risk of fishy taint in eggs.
Wheat flour starch granule‐size distribution and rheological properties of dough. Part 2. Extensographic measurements
Authors: Šebečič Bl. , Šebečič B. 
Published: November 2006

AbstractTo examine the interdependence of granulometric composition of wheat flour starch and rheological properties of dough, the content of starch fractions, i.e. the granulometrical and statistical parameters of granule‐size distribution determined in previous work (Nahrung 39 (1995) 106), were correlated with extensograms evaluated after AACC and ICC criteria as well as after recently proposed criteria by Balint et al. (Nahrung 35 (1991) 721). Data show that smaller granules (6.5–19.5 μm in diameter) significantly increase the extensibility of dough (r – 0.600, P < 0.05) and decrease resistance to extension (r = 0.756, P < 0.005) as well as the ratio between resistance and extensibility (r = 0.855, P < 0.005), respectively. Granules > 27.5 μm increase resistance to extension (0.1 > P > 0.005). Significant correlation between parameters of extensograms and different statistical, i.e. granulometrical parameters of granule‐size distribution suggests the possibility that granule‐size distribution can influence the visco‐elastic properties of dough (elastic deformation in particular) under the conditions of extensographic measurements, as well.
Influence of harvesting and drying techniques on microflora and mycotoxin contamination of figs
Authors: Özay G. , Aran N. , Pala M. 
Published: November 2006

AbstractMould growth and mycotoxin (aflatoxins and ochratoxin A) formation were examined in the 1993 dried figs crop. The relationships between mould/mycotoxin contamination and orchard conditions, different harvesting techniques, harvesting time and intactness of fruits were investigated. The fruits were examined during drying and effects of different pretreatments, sun drying and solar drying on the mould and mycotoxin contamination in figs were also studied.Aflatoxins (B1, B2, G1 and G2) were not present in the firm or shrivelled ripe figs. Among the samples examined during drying, only one of the 32 samples was found to be aflatoxin positive. Ochratoxin A was not detected in any of the samples analysed. The moisture content, aw and pH values of full ripe and shrivelled fruits were suitable for mould growth and mycotoxin formation while these parameters in pretreated and dried fruits were found to be too low to allow such outcome. It was observed that harvesting the fruit by hand‐treating with different solutions and application of solar drying were effective in reducing contamination level.
Equilibrium moisture characteristics of dried eggplant and okra
Authors: Ayranci E. 
Published: November 2006

AbstractEquilibrium moisture characteristics of dried eggplant and dried okra were studied at 20 °C and 27 °C Moisture sorption isotherms of these dried vegetables were derived using the static method. Sorption data were treated according to some well‐known isotherm equations. The parameters of these equations were obtained and goodness of fit of data to these equations were tested. The trends in monolayer moisture contents at different temperatures were examined. Finally, the heat of sorption data were derived with the use of Clausius Clapeyron type equation and presented in graphical form.
Preparation and characteristics of coprecipitate proteins from oilseeds and legumes seeds
Authors: Youssef A. M. , Abu‐Foul N. S. , Moharram Y. G. 
Published: November 2006

AbstractThe chemical composition as well as functional and nutritional properties of the coprecipitated proteins from a mixture of legumes and oilseeds sources and of the protein isolates of each vegetable source were studied. The results indicated that the protein coprecipitates of the vegetable sources blends show higher nutritional values, better functional properties, lower levels of antinutritional factors, better in vitro protein digestibility and better composition of essential amino acids than those of their individual protein isolates.
Bioavailability of iron in selected cereal based preparations — An in vitro study
Authors: Sunitha S. V. , Urooj Asna , Puttaraj Shashikala 
Published: November 2006

AbstractThe percent available iron was determined in some commonly consumed cereal‐based Indian food preparations using an in vitro method. Proximate composition, including ash content (by both dry and wet methods) of the food preparations was analysed. In rice‐based preparations total iron content analysed after dry and wet ashing showed significant differences. Total iron content (by dry ashing) of the foods ranged from 5.0 (Pongal) to 42.3 mg (upittu). The percent soluble iron ranged from 74.2% (rice flakes upittu) to 12.2% (upittu). However, ionizable iron which ranged from 52.1% (Pongal) to 6.3% (upittu) depending on the food preparation, did not show similar pattern. Ionizable iron which varied significantly between foods showed a significant positive correlation with energy. The results not only emphasize the fact that it is important to understand the interaction between different foods but also that of meal composition for bioavailability of iron.
Effect of various domestic processing and cooking methods on the HCl‐extractability of minerals from pea seeds
Authors: Bishnoi S. , Khetarpaul N. 
Published: November 2006

AbstractVarious domestic processing and cooking methods like soaking (6, 12 and 18 h), dehulling of soaked pea seeds, ordinary and pressure cooking of unsoaked, soaked and soaked‐dehulled pea seeds and sprouting for varying periods (12, 24 and 48 h) brought about a significant (P < 0.05) improvement in HCl‐extractability of minerals, an index of their bioavailability to the human system. Sprouting was noticed to be the best processing method followed by pressure cooking and ordinary cooking of soaked‐dehulled pea seeds for remarkably enhancing the availability of dietary essential minerals i.e. calcium, phosphorus, iron, copper and zinc.
Lipid oxidation in chicken as affected by cooking and frozen storage
Authors: Abdel‐Kader Z. M. 
Published: November 2006

AbstractOxidative rancidity in fresh, frozen and cooked chicken breast and leg meat was evaluated by measuring malondialdehyde (MDA) in fat from meat with an improved 2‐thiobarbituric acid (TBA) assay with antioxidant protection, and by measuring the relative fluorescent products of organic and aqueous layers from Folch extracted meat. Fresh samples were frozen for 3 and 6 months at −18 °C and cooked in convection and microwave ovens. Frozen storage for 3 and 6 months either before cooking or after convection and microwave cooking substantially increased MDA concentrations in fat from meat, whereas cooking was more effective in generating fluorescent products. There were no significant differences in free MDA concentrations or TBA numbers in chicken meat between convection and microwave cooking methods. The certain secondary fluorescent products were significantly higher in meat cooked by convection oven. The initial levels of either MDA or fluorescent products in meat are of primary importance in determining the final MDA and fluorescence levels after processing.
Comparing effects of washing, thermal treatments and gamma irradiation on quality of spieces
Authors: Zaied S. E. A. Farag , Aziz N. H. , Ali A. M. 
Published: November 2006

AbstractSelected five spices were treated with simple natural methods as washing with pure tap water then drying at room temperature, thermal treatment at 70 °C/15 minutes besides irradiation with 5.0 and 10 kGy. The evaluation of the used treatments efficiency depends on microbiological and chemical studies. The results show that untreated samples were highly contaminated with pathogenic and toxigenic microbes. Gamma irradiation was effective in decontamination especially 10 kGy but caused losses in major components of flavour as anethol, mechavicul, anise‐aldehyde in anise, β‐pinen and cineol in black pepper. Also, irradiation induced the changes of monoterpene hydrocarbons to alcohol terpens in essential oils of black pepper.Thermal treatment reduced the microbial count and pathogenic microbes to the same safe range as an irradiation dose of 5 kGy. Thermal techniques improved the flavour, as anisealdehyde in fennel, anethol in anise and B‐pinen in black pepper. Washing of the spices removed slightly the microbes but revealed no changes in flavour except the anise flavour which increased markedly.Finally, thermal and washing treatments could be recommended as simple natural techniques to produce spices with good flavour and in safe range for hygienic quality comparing with sterilized dose 10 kGy.
Composition and some physical properties of different pea cultivars
Authors: Borowska J. , Zadernowski R. , Konopka I. 
Published: November 2006

AbstractThe basic composition and physical properties such as firmness and cookability were determined for eight varieties or lines of pea and field pea. The discriminant components of peas were protein (19.5–28.9%), starch (46.1–54.6%) and in a less extent acid detergent fibre (10.0–11.6%) and dietary fibre (18.1–21.1%). The resistance of raw peas to crushing, expressed by the minimum destruction force, was highly differentiated (286–468 N).The relationships between the firmness of peas and their size, and the content of protein or acid detergent fibre, were found. High differences in cookability of peas did not correlate with either the firmness of raw peas or their use value.
Effectiveness of microwave based digestion procedures for the demineralization of human milk and infant formulas prior to fluorometric determination of selenium
Authors: Alegría A. , Barberá R. , Farré R. , Lagarda M. J. , Lorente R. M. , Torres A. 
Published: November 2006

AbstractThe use of two types of microwave oven, one domestic (A) and the other specially designed for laboratory (B) for microwave‐based digestion, to destroy the organic matter in milk and infant formulas prior to fluorometric determination of selenium is studied in order to check their applicability and reliability.In both systems the best results were obtained using the acid mixture HNO3—H2O2, and additional treatment with perchloric acid (60%) in a Thermoblock. The application of two different microwave‐based digestion procedures to infant formulas was free of interferences. In the case of human milk, it was necessary to use the standard addition method.Values obtained for detection and quantification limits, precision and accuracy of the fluorometric determination of selenium show the usefulness of both digestion procedures. The oven designed for laboratory use (B) is preferential as it permits simultaneous digestion of eight samples.
Rheological and microstructural characterization of double cream cheese
Authors: Sanchez C. , Beauregard J. L. , Bride M. , Buchheim W. , Hardy J. 
Published: November 2006

AbstractFirmness at 5 °C, dynamic viscoelastic moduli (G' G) and capillary extrusion profiles at 20 °C, were obtained on double cream cheese after the different steps of processing (curd obtention, mixing at 70 °C and 500 r.p.m. with heat‐denatured WPC, heating at 85 °C, homogenizing at 20 MPa (1st stage) and 5 MPa (2nd stage) and cooling to 20 °C and 13 °C) and storage 7–9 days at 5 °C. It was found that double cream cheese became firmer and more elastic after heating and homogenization, although it became softer and more viscous after mixing and cooling. Transmission Electron Microscopy (TEM) and cryo‐Scanning Electron Microscopy (SEM) micrographs showed that rheology results could be related to aggregation (during heating and homogenization) and disruption (during cooling) of milk fat globule/casein complexes. Dispersion of homogenization clusters after cooling, and aggregation of milk fat globules during storage caused double cream cheese structural instability to appear. It was suggested that the heterogeneity of capillary extrusion profiles could be quantified through application of fractal concepts and Fourier analysis and related to structure and texture of double cream cheese.
Limited tryptic hydrolysis of legumin from faba bean (Vicia faba L.): formation of an [unequal] subunit pattern
Authors: Dudek Steffi , Horstmann Ch. , Schwenke K. D. 
Published: November 2006

AbstractOne‐dimensional and two‐dimensional SDS‐PAGE and Hydrophobic Cluster Analysis (HCA) were used for investigating the course of limited tryptic hydrolysis of faba bean legumin.SDS‐PAGE revealed the formation of an “unequal” subunit pattern, characterized by 30 and 50 kDa subunits, which could be related to the A‐ and B‐type subunits of legumin. These subunits followed different pathways during the non‐cooperative part of the tryptic hydrolysis.HCA revealed structural differences between the subunit types and gave arguments to predicted potential splitting sites. A‐ and B‐subunits differ in extension and composition of the flexible segments as well as in the interior of the C‐terminal side, as in the C‐termini of the α‐chains which confirmed the observed non‐uniform hydrolysis pattern. The HCA plot demonstrated that the number and exposition of flexible surface elements was changed by limited hydrolysis. This result was discussed with regard to the influence of tryptic modification on the emulsifying properties of legumin.
Recent advances in enzymatic modifications of food proteins for improving their functional properties
Authors: Chobert J. M. , Briand L. , Guéguen J. , Popineau Y. , Larré C. , Haertlé T. 
Published: November 2006

AbstractThe tailoring of food proteins by enzymes is a powerful tool to improve their functional properties. Mainly proteinases from various origins have been used for such purposes. Controlled proteolysis leads generally to more soluble products with improved emulsifying properties but relatively poor foaming properties. This latter was the case in our studies on proteolysis of wheat gluten. We also have demonstrated that polypeptides characterized by a high functionality could be produced by proteolysis of wheat gluten. Depending on the conditions of the proteolytic attack, the cleavage sites as well as the type of generated peptides could be modified. In the case of milk proteins, peptic action on the proteins in ethanolic medium or on moderately esterified proteins results in unique fragmentation. Besides fragmentation achieved by proteases, the cross‐linking of proteins to yield higher molecular size forms with transglutaminases was shown to improve the functional properties of proteins. These enzymes catalyse the binding of amines to proteins, cross‐link the polypeptide chains and deamidate the glutaminyl residues. In the case of soybean isolates, gelification was obtained with lower protein concentrations. In the case of wheat gliadins, enzymatic deamination increased drastically the solubility in a wide range of pH. Additionally, enzymatically deaminated gliadins were shown to be very efficient in stabilizing emulsions, due to the formation of soluble polymers.
Thermodynamic approach to the selection of polyuronide sequestrants for preventive and medicinal nutrition
Authors: Braudo E. E. , Danilova I. V. , Dianova V. T. , Kobak V. V. , Plashchina I. G. , Sidorov E. V. , Bogatyrev A. N. 
Published: November 2006

AbstractAn approach to the analysis of isotherms of cooperative binding is developed that allows to calculate approximately affinity profiles, i.e. dependencies of binding constants on binding densities. The comparison of the affinity profiles of the interactions of Ca2+ and Sr2+ ions with sodium pectate as well as sodium alginates with the different content of the blocks of α‐L‐guluronic acid residues (GG‐blocks) and blocks of mixed composition showed that (1) pectate has higher affinity to both ions as compared with alginates; (2) the affinity of pectate to Ca2+ ions is comparable to its affinity to Sr2+ ions but in the case of Ca2+ ions the maximum of the affinity profile falls on the substantially lesser value of the binding density in comparison to Sr2+ ions that seems to be unfavorable from the standpoint of the use of this polyuronide in preventive or medicinal nutrition; (3) the affinity of both alginates to Sr2+ ions at relatively low binding densities exceeds their affinity to Ca2+ ions; (4) the affinity of alginates to Sr2+ ions increases with the increase in the content of GG‐blocks, whereas the affinity to Ca2‐ ions practically does not depend on the composition of the alginate; (5) the maximum binding density of Sr2+ ions to the alginates approximately corresponds to the content of GG‐blocks. These results corroborate the practice of the use of alginates rich in residues of α‐L‐guluronic acid for the removal of radioactive strontium from the digestive tract. The binding constants of Pb2+ ions to pectate over a wide range of binding densities are more than an order of magnitude greater than those of alkali‐earth metal ions.
Wheat flour starch granule‐size distribution and rheological properties of dough. Part 4. Farinographic measurements
Authors: Šebečić Bl. , Šebečić B. 
Published: November 2006

AbstractTo examine how granulometric composition of wheat flour starch affects the rheological properties of dough in conditions of farinographic measurement, the content of starch fractions, i.e. the granulometrical and statistical parameters of granule‐size distribution determined previously (Nahrung 39 (1995) 106), were correlated with farinograms evaluated after AACC and ICC criteria as well as after criteria proposed by Pinter et al. (Bull. Sci. Sect. A Yougosl. 21 (1976) 217) and suggested as the most exact ones. Data show that fraction of very small granules causes weakening of dough while the most represented granules sized 5–16 μm in diameter (mean content 47.3%) influence the shape of the first part of farinographic curve causing dough development time, stability, time to breakdown and quality number to be higher. The higher the content of larger granules (>16 μm) the lower the softening of dough and farinographic area. The higher the mean value of granules' size the higher the time to breakdown and the lower dough weakening; the higher the most frequently occurring granule size the smaller the degree of weakening of dough and farinographic area. Significant correlation between parameters of farinogram and different statistical, i.e. granulometrical parameters of granule‐size distribution (0.05 ≥ P < 0.005) confirm that granule‐size distribution can affect behavior of dough during mixing in the farinograph.