bluuebunny/crossref_metadata_2025_split huggingface dataset:
The linamarase of Leuconostoc mesenteroides: Production, isolation and some properties
Authors: Okafor Nduka , Ejiofor Michael A. N. 
Published: October 2006

AbstractLeuconostoc mesenteroides was found to produce highly active linamarase when linamarin was incorporated in its growth medium. The enzyme was isolated from the bacterium and partially purified using diethylaminoethyl (DEAE) cellulose. Its activity was measured spectrophotometrically using linamarin extract. This yielded 62.2 mg CN− g−1 of linamarin. A study of some of its properties showed it was active in the temperature range of ‐10 to +45°C, with an optimum at 29°2°C. Activity was observed over a wide pH range, 4.0–8.0, with optimum at 6.0–6.5. Its pH of stability was 5.5–7.5, while above pH 8.0 there was a rapid loss of activity. Incubating the enzyme at 50°C led to loss of over 90% of its activity within 18 min. The optimal substrate concentration was 0.15–0.20 ml−1. Whereas above 0.25 mg ml−1 there was no observable increase in activity, loss of activity became more pronounced below 0.10 mg ml−1 of substrate.
The composition of orange roughy (Hoplostethus atlanticus) roe lipids
Authors: Body Denis R. 
Published: October 2006

AbstractLipid analysis was carried out on orange roughy (Hoplostethus atlanticus) roe oil. Various chromatographic analytical techniques were compared and it was shown, although total orange roughy oil was rich in wax esters, that roe oil contained triacylglycerol and phospholipids as the principal components. The fatty acid content of the individual lipids (except wax esters) had 16:0, 18:1, 20:1, 20:5 and 22:6 as their major constituents.
The bread baking quality of six wheat starches differing in composition and physical properties
Authors: Soulaka Amjad B. , Morrison William R. 
Published: October 2006

AbstractStarch was isolated from six types of wheat and separated into large A‐granule and small B‐granule fractions which exhibited a suitable range of properties. Respective amylose contents were 28.6–31.0% and 25.1–31.5%, lysophospholipids 707–1014mg 100 g−1, and 1058–1398 mg 100 g−1, and gelatinisation temperatures (GT) by differential scanning calorimetry (DSC) 58.4–62.7°C and 60.5–64.5°C. The A‐ and B‐granule fractions were remixed in various proportions and reconstituted with freeze‐dried gluten and freeze‐dried water‐solubles from flour to test the effects of changes in the properties of the total starch, A‐granule or B‐granule fractions, and the effects of various proportions of B‐granules on the quality of bread. The specific volumes of the loaves were not affected by starch amylose or lipid content, but were significantly correlated with either the GT of the total starches or their A‐granules. The optimum proportion of B‐granules was 25–35% by weight, but their GT had no effect on loaf specific volume. Staling changes were quantified from crumb compressibility measurements and the enthalpy of the endotherm for gelatinisation of retrograded amylopectin in stored breadcrumb, measured by DSC. Initial and limiting moduli of crumb firmness were correlated with loaf specific volume and starch GT, but rate and time constants calculated from the Avrami equation were independent. Rate and time constants and limiting enthalpy values calculated from the DSC results were independent of all other measured parameters.
Processing, suitability and nutritive value of field bean seeds after germination
Authors: Bednarski Wlodzimierz , Tomasik Jan , Piatkowska Barbara 
Published: October 2006

AbstractAn attempt was made to obtain hydrolysates from field bean seeds after germination. The activity of native proteolytic enzymes, ascorbic acid and phytate phosphorus contents, as well as the activity of proteolytic enzyme inhibitors were studied, as influenced by seed steeping, water acidity and aerating conditions. Germinated field bean seeds were found to be suitable for hydrolysate production. The enzyme activity, as well as the contents of compounds responsible for the nutritive value of seed was determined and depended on germinating conditions.
Nutritive value of mango seed kernel
Authors: Dhingra Sukhsatej , Kapoor Amin C. 
Published: October 2006

AbstractSeed kernels of two cultivars (Chausa and Dusheri) of mango (Mangifera indica) were analysed for chemical composition, lipid classes, fatty acid composition, amino acid profile and chemical evaluation of protein quality. The seed kernels constituted about 18% of the total fruit and had 5% protein, 6–7% crude fat, 0.19–0.44% tannins, iodine value of 34–44 and saponification number 202–213. Oleic acid (42%) and stearic acid (39%) were the principal fatty acids in the oil. The in vitro digestibility was low in these cultivars, possibly due to the presence of tannins. Sulphur‐containing amino acids (methionine+cystine) and isoleucine were the limiting amino acids in Chausa and Dusheri, respectively. The essential amino acid index and protein quality index were high, thus indicating the good quality of the protein in mango seed kernel.
A simplified method for the extraction of the metals Fe, Zn, Cu, Ni, Cd, Pb, Cr, Co and Mn from soils and sewage sludges
Authors: McGrath Stephen P. , Cunliffe Caroline H. 
Published: October 2006

AbstractThe method described for digestion of soil samples with aqua regia is simple, flexible and safe to operate with large sample throughout. At least nine metals can be determined in the resulting solutions with errors of <5%. The results compare favourably with those from reflux aqua regia and averaged 88% of the certified total values for reference soils and 88% of those for reference sewage sludges.
The kinetics and mechanism of caffeine infusion from coffee: The effect of roasting
Authors: Spiro Michael , Hunter Julia E. 
Published: October 2006

AbstractRates of extraction of caffeine into water at 80°C were measured for green and roasted Kenyan arabica coffee beans. The green beans were roasted to controlled extents in a Moda coffee roaster, ground, and sieved to a size range 0.85–1.18 mm. Certain physical properties (weight loss, colour, bean volume and infusion pH) were determined for each product. The half‐time of caffeine infusion did not change significantly on light roasting but dropped by 40% on more severe treatment and by a further 30% when roasted to scorching. The activation energy also decreased on strong roasting. The kinetic parameters have been correlated with the physical properties of the coffees and with the chemical and physical changes of roasting.
Tryptophan determination of food proteins by h.p.l.c. after alkaline hydrolysis
Authors: Nielsen Henrik K. , Hurrell Richard F. 
Published: October 2006

AbstractThe alkaline hydrolysis of proteins prior to tryptophan analysis has been evaluated, and a method for the measurement of tryptophan by reverse phase h.p.l.c. after alkaline hydrolysis has been proposed and compared with published methods. Hydrolysis with either LiOH or NaOH gave similar results. Tryptophan values and the recovery of added 5‐methyltryptophan were similar when hydrolysis was made under tap‐water vacuum (1500 Pa) or at high vacuum (2 Pa). Partially‐hydrolysed starch reduced the losses of tryptophan during hydrolysis better than thiodiglycol. High levels of indolyl‐3‐propionic acid or 5‐methyltryptophan did not further improve tryptophan recovery. 5‐Methyltryptophan is the preferred internal standard; its recovery after hydrolysis more closely resembled that of protein‐bound tritiated tryptophan from goat casein than did the recoveries of α‐methyltryptophan or free 14C‐tryptophan. Under some conditions, the recovery of protein bound tryptophan was lower than the recovery of free tryptophan. The stability of tryptophan in hydrolysates was improved by using a phosphate buffer pH 7.0 containing 0.02% sodium azide.
Structural changes in wheat straw components during decay by lignin‐degrading white‐rot fungi in relation to improvement of digestibility for ruminants
Authors: Agosin Eduardo , Monties Bernard , Odier Etienne 
Published: October 2006

AbstractStructural changes and resulting in‐vitro dry matter digestibility (IVDMD) were determined during the course of solid‐state fermentation of wheat straw using the lignin‐degrading white‐rot fungi Sporotrichum pulverulentum, Pycnoporus cinnabarinus and Cyathus stercoreus. The first fungus grew very rapidly on straw but degraded hemicelluloses and cellulose non‐selectively resulting in very low IVDMD increases (50% after 35% weight loss). P. cinnabarinus and C. stercoreus preferentially degraded hemicelluloses achieving high improvements in IVDMD (maximum increase of 63 and 94%, respectively) with limited dry weight losses (12 and 18% after 7 and 13 days, respectively). The three fungi exhibited some selectivity among the individual hemicellulose components: O‐acetyls were removed essentially at the same rate as xylan, while uronic acids accumulated as incubation proceeded. Conversely, the arabinose content decreased rapidly, especially with C. stercoreus and P. cinnabarinus, suggesting that removal of this pentose was partly responsible for digestibility improvement. Esterified phenolic acids were rapidly degraded during the first stages of decay by all three fungi although P. cinnabarinus and C. stercoreus degraded ferulic acid faster than p‐coumaric acid. Lignin was preferentially degraded compared to polysaccharides by all three fungi. The amount of lignin removed, as determined by Klason, correlated well with IVDMD improvement (r=−0.97), while acid detergent lignin (ADL) showed a lower correlation (r=‐0.86). Acidolysis yields of decayed lignin pointed to preferential degradation of β‐O‐4 ether linked units by the fungi. Syringyl units were removed faster than guaiacyl units only after 5 to 10% weight loss was obtained.
A sensitive monoclonal‐antibody‐based test for gluten detection: Studies with cooked or processed foods
Authors: Skerritt John H. , Smith Robyn A. 
Published: October 2006

AbstractA method for detection of wheat, rye, barley and oat proteins in a wide range of foods, including baked goods and processed meats has been developed. The procedure requires immobilisation of food extracts upon nitrocellulose paper followed by treatment with an enzyme‐conjugated monoclonal antibody. Upon addition of the appropriate enzyme substrate, gluten‐containing foods yield purple spots; a wide range of non‐gluten common food proteins did not react. The method has several advantages over other means of detecting cereal protein, such as electrophoresis. It is rapid, requiring little sample preparation, and does not require sophisticated equipment or prior knowledge of electrophoretic patterns of common non‐cereal food proteins. Since the method may be used with cooked or baked foods, it should be suitable for food‐monitoring applications.
The nutritional quality of two types of fish silage for broiler chickens
Authors: Johnson Ray J. , Brown Nick , Eason Paul , Sumner John 
Published: October 2006

AbstractFish waste was ensiled either by acidification with formic acid or by fermentation with a bacterial starter culture and molasses. The resulting liquids were mixed with wheat bran (85:15 w/w liquid: bran) and dried (70°C) to produce acid silage meal (ASM) and fermented silage meal (FSM). ASM and FSM were incorporated into wheat‐based diets at 25, 50 and 100 g kg−1 at the expense of soya bean meal. There were two control diets, one which contained soya bean meal as the predominant protein supplement and a second in which fish meal (50 g kg−1) was added at the expense of some of the soya bean meal. Starter diets (13.25 MJ ME kg−1, 12 g kg−1 lysine) were fed from 1‐day‐old to 21‐days‐old and finisher diets (13.25 MJ ME kg−1, 9.5 g kg−1 lysine) were fed from 22 to 42‐days‐old to six replicates each of five birds. Birds were reared in raised‐wire cages, and feed intake, liveweight and mortality were recorded. There were no significant effects of dietary inclusion of either ASM and FSM on the performance of broiler chickens relative to those fed on control diets. FSM contained less crude protein and amino acids than ASM. The recovery of amino acids relative to the total crude protein content from FSM was only 78.7%, presumably as a result of formation of Maillard reaction products during drying.
The effects of increasing yields on the macro‐ and microelement concentrations and offtakes in the grain of winter wheat
Authors: McGrath Stephen P. 
Published: October 2006

AbstractThe variations in major and minor element concentrations in winter wheat grain from a UK survey and from three experiments on farms with high yields (>10tha−1) are given. In the survey, the concentrations of P, K, S, Ca and Mg varied twofold, the elements Fe, Zn and Cu varied threefold, whilst Mn varied by a factor of five. Small varietal differences in grain composition were detected. In the field experiments only the concentrations of Fe, Zn, Cu, Mn and S changed significantly as yields increased, and most of the changes were positive, except for Mn, which did not increase with yield. Foliar fungicidal sprays containing Mn increased grain Mn in 1981 and 1982, but S‐containing sprays did not alter grain S in 1983. The offtakes of all the elements studied are given both nationally and for high and low yields on the three farms. These offtakes are compared with the inputs of P, K and Mg in fertilisers and the likely inputs of S from the atmosphere.
The production of naturally fermented fish silage using various lactobacilli and different carbohydrate sources
Authors: Van Wyk Hercules J. , Heydenrych Christine M. S. 
Published: October 2006

AbstractThe suitability for fish silage‐making of eight different Lactobacillus cultures was investigated. The industrial by‐products whey powder and molasses, as well as refined sugar, were tested as fermentation substrates. Using the information obtained two batches of fish silage were made at local white fish processing plants on a semi‐commercial basis and subsequently successfully used on local cattle and pig farms.
Nutritional evaluation of ethanol extracted Madhuca (Madhuca butyraceae) seed flour
Authors: Shanmugasundaram T. , Venkataraman L. V. 
Published: October 2006

AbstractDefatted Madhuca flour is toxic due to the presence of saponins. Alcohol, 20–95%, was used to remove the saponins and it was found that two stage 60% ethanol extraction removed 90% of the saponins present in the flour. Rat feeding trials using the ethanol extracted flour at 10 and 15% protein levels yielded PER of 0.8 and 1.5 respectively and did not show any ill effects other than minor cytoplasmic vacuolation in liver and kidney in histological studies.
The effect of varying autoclaving conditions and added sodium hydroxide on amino acid content and nitrogen characteristics of feather meal
Authors: Papadopoulos Manthos C. , El‐Boushy Adel R. , Roodbeen Albertus E. 
Published: October 2006

AbstractThe effects upon amino acid content and nitrogen characteristics of feather meal subjected to varying lengths of processing time (30 to 70 min) moisture content (50 to 70%) and added NaOH (0.2 to 0.6%) were studied by multiple regression techniques. All test products were autoclaved at constant pressure of 345 kPa. The results obtained showed that prolonged processing periods and increased concentrations of NaOH had a substantial effect on the amino acid contents and in particular on the essential ones. There was a marked degradation of cystine, and smaller losses of lysine and methionine. Most of the amino acid contents were lower in the meals with a higher moisture content. In vitro protein digestibility and solubility in alkali and acid, were generally increased by prolonged processing conditions.It was concluded that the inverse relationship between amino acid content and nitrogen characteristics should be taken into account for feather meal evaluation. Higher values for in vitro protein digestibility and solubility were considered to be favourable unless other structural modifications to the protein affect its nutritional value.
Polyphenoloxidase from guava (Psidium guajava L.)
Authors: Augustin M. A. , Ghazali Hasanah M. , Hashim Hasimah 
Published: October 2006

AbstractPolyphenoloxidase (PPO) was isolated from guava (Psidium guajava L., cv. Kampuchea). Purification by acetone precipitation and dialysis of the Amicon concentrate resulted in 4.9‐fold and 17.2‐fold purification of the dialysed crude extract respectively. Polyacrylamide gel electrophoresis indicated that PPO had a molecular weight in the region of 120000–140000. The pH optimum of the enzyme was found to be 7.2. Heat inactivation studies showed that heating for 1.1, 3.5, and 10.1 min at 75, 65 and 55°C respectively caused a 50% loss in enzymic activity. The enzyme‐catalysed browning reaction was significantly inhibited in the presence of sodium metabisulphite, L‐cysteine hydrochloride and ascorbic acid.
Determination of sugars in tropical root crops using 13C N.m.r. spectroscopy: Comparison with the h.p.l.c. method
Authors: Tamate Jerry , Bradbury J. Howard 
Published: October 2006

AbstractThe 13C nuclear magnetic resonance (n.m.r.) spectrum of sugars normally present in foods, viz. glucose, fructose, sucrose, maltose and raffinose contains resonances that are diagnostic of each sugar. The quantity of each sugar is determined by measurement of the ratios of the peak heights of the sugar resonances compared with peak height of an internal standard, present at constant concentration in all solutions. A linear calibration relationship between the peak height ratio and concentration is established for single resonances of glucose and fructose and for two resonances of each of sucrose, maltose and raffinose. Samples of sweet potato and taro flour dried at 40°C, were blended with 80% ethanol, the sugars were extracted and analysed by 13C n.m.r. and h.p.l.c. Both methods gave similar results and have similar degrees of reproducibility. The n.m.r. method is useful for quantitation of sugars and identification of other molecules extracted from the food, but requires more material than does h.p.l.c. Drying at 40°C causes a decrease in sucrose content and increases in glucose, fructose and maltose which partly compensate for the loss in sucrose. There is considerable variability of the sugar content between different sweet potato tubers and between different taro corms of the same cultivar as well as across different cultivars. For sweet potato the total sugar content is 0.6‐3.6% fresh weight, with considerably more sucrose present than glucose, fructose and maltose. With taro total sugar content is 0.2‐0.8% fresh weight. Raffinose is present in one sample only.
Kinetics and equilibria of tea infusion: Rates of extraction of theaflavin, caffeine and theobromine from several whole teas and sieved fractions
Authors: Price William E. , Spiro Michael 
Published: October 2006

AbstractThe rates of infusion of theaflavin and caffeine into water at 80°C have been measured for Kapchorua Pekoe Fannings, Kapchorua Pekoe Dust, Betjan Flowery Broken Orange Pekoe and Rupai Flowery Orange Fannings whole teas and sieved fractions. For Kapchorua PF fractions the rates of theobromine infusion were also determined. Caffeine always infused faster than theobromine, and both infused faster than theaflavin. Rate constants were obtained from the slopes of first order kinetic plots which yielded straight lines with small intercepts. The rate constants for all three constituents increased by a factor of 2.2 as leaf size decreased from 850–1000μm to 500–600μm. The rates of extraction from whole teas varied more than fourfold. Kapchorua PD gave the most rapid rates and Betjan FBOP the slowest. Comparisons of similarly sized fractions of teas showed that leaf size distributions accounted for half these differences and the intrinsic properties of the leaf for the remaining factor of two. The Kenyan CTC teas gave higher rate constants than the Indian orthodox teas. From the rate constants, the effective diffusion coefficients for theaflavin and caffeine in Betjan FBOP leaf were calculated and found to be some 100 times smaller than in water. This shows the diffusion processes within the leaf to be complex ones.
Changes in sterol and phospholipid composition of apples during storage at low temperature and low oxygen concentration
Authors: Bartley Ian M. 
Published: October 2006

AbstractFree sterol and phospholipid in the cortical tissue of apple were determined during storage of the fruits in air at 12 and 3.5°C and in 2 kPa O2 (98 kPa N2) at 3.5°C. In air at 12°C, the sitosterol content declined slightly (about 4%) during fruit ripening whilst phospholipid increased about 8%. At 3.5°C in air and 2 kPa O2, sitosterol content increased by 16% and phospholipid by 25–31%. The increase in phospholipid in 2 kPa O2 occurred more slowly than in air. Transfer of apples to air after 33 or 64 days in 2 kPa O2 led to rapid accumulation of phospholipid in the fruit (20% and 10%, respectively) compared with apples maintained in 2 kPa O2. An increase in concentration of phosphatidylcholine (PC) accounted for most of the change observed in total phospholipid.
Formation of two types of gels from bovine myosin
Authors: Hermansson Anne‐Marie , Harbitz Ole , Langton Maud 
Published: October 2006

AbstractMyosin was isolated from bovine m. semimembranosus and gels were formed by heat treatment at different pH values and ionic strengths. The gels were subjected to rigidity measurements and their microstructure was studied by scanning electron microscopy. This article provides evidence that myosin can form two completely different gel structures in the pH range 5.5–6.0, depending on ionic strength. Fine stranded gel structures were formed at low ionic strength (0.25M KCl), whereas coarsely aggregated gel structures were formed at high ionic strength (0.6M KCl). The fine stranded structure had a higher rigidity than the coarsely aggregated structure. It was found that all fine strand myosin gels were formed from turbid solutions and the aggregate gels from clear solutions. When the pH was lowered to 4 in 0.6M KCl a strand‐type gel structure formed spontaneously on dialysis, even without heat treatment. This structure did not change in character on heating. It was concluded that the conditions required for the formation of strand‐type myosin gels were already present before the heat treatment and that the strands were made up of myosin filaments at certain pH and ionic strength combinations, which produced a turbid solution. The strand‐type structures were considered specific with regard to myosin interactions which was not the case for the aggregated structures. Variation of the heating temperature in the range 55 to 65°C had no major effect on the type of structure formed.