bluuebunny/crossref_metadata_2025 huggingface dataset:
Replacement of fishmeal by low‐cost animal protein as a quality fish feed ingredient for indian major carp, labeo rohita, fingerlings
Authors: Begum Nurun N , Chakraborty Subhash C , Zaher M , Abdul Mazid M , Gupta Mudadugu V
Published: November 2006

Five formulated diets containing 350 g kg‐1 crude protein were prepared replacing 0, 25, 50, 75 and 100% of the fish meal content which silkworm pupae (Bombyx mori) and clam meat as a dietary protein source, and were fed to Indian major carp (Labeo rohita) fingerlings of 2.0–2.2 g size under laboratory conditions. A growth study over a period of 90 days showed that a diet containing 50% of its protein as fishmeal had significantly higher (P≤0.05) growth with values of 1.64, 1.92, 1.48 for specific growth rate, food conversion ratio and protein efficiency ratio, respectively. Significantly lower growth (P≤0.05) was observed with diets having all or none of its protein as fish meal. This experiment with Labeo rohita fingerlings revealed a significantly better utilisation of the diet when half the protein in a fishmeal diet was replaced by protein in the form of silkworm pupae and clam meat.
Preliminary development of intermediate moisture, pasteurised mackerel (scomber japonicus marplantensis) chunks
Authors: Pascua Gabriela L Sanchez , Casales Maria R , Yeannes Maria I
Published: November 2006

The objective of this study was to develop an intermediate moisture, pasteurised mackerel product combining the lowering of water activity (aw) by means of selected solutes with pasteurisation. Loss of water was achieved by soaking in an equilibrium solution containing glycerol, salt, and potassium sorbate. An optimum cooking time of 20 min in the infusion solution and an optimum immersion time of 20 h in the same solution were determined. A final aw value of 0.89 was obtained. These parameters were selected taking into account the sensory assessment, since the main problem in this kind of food is acceptance by the consumer. The product was pasteurised at 90°C for 40 min. The product obtained by this combination of conditions had a moderately sweet taste and a succulent texture.
Detection of roquefortines in penicillium roqueforti isolated from moulded maize silage
Authors: Ohmomo Sadahiro , Kitamoto Hiroko Kuze , Nakajima Tomoyoshi
Published: November 2006

A strain (number 19) having the ability to produce some indole alkaloids was isolated from moulded maize silage, and was identical with Penicillium roqueforti. Roquefortine C was isolated from the culture broth in crystalline form as a main alkaloid and was identified as a minor alkaloid by thin‐layer chromatography (TLC) in a maize silage inoculated with the strain. Further, roquefortine A, B and D together with festuclavine were identified by TLC. The alkaloid contents in silage were analysed to be 2.40 mg kg‐1 (roquefortine A) and 1.66 mg kg‐1 (roquefortine C).
Analysis of volatile compounds from supercritical extracted soybeans by headspace gas chromatography and thermal desorption of a polymer adsorbent
Authors: Snyder Janet M , King Jerry W
Published: November 2006

Soybean flakes were extracted with supercritical carbon dioxide to produce a solvent‐free, good‐quality soybean oil. Volatile compounds from the supercritical fluid extracted (SFE) oil and from a hexane‐extracted crude soybean oil were analyzed by dynamic headspace gas chromatographic methods to determine qualitative differences between the extraction methods. The major difference in the volatile profiles was the higher concentration of hexane in the solvent‐extracted oil. During the SFE process, volatile compounds were trapped on a porous polymer trap attached at the exhaust port of the SFE apparatus. The volatile profile obtained from the sorbent trap was found to be similar to the headspace profile from the SFE/soybean oil removed during the same extraction. In addition, crude soybean oil was heated in a stirred reactor and the volatiles, which were stripped by supercritical carbon dioxide in an attempt to improve oil properties, were collected on sorbent traps and analyzed by the above method for comparison. The described methodology permits the characterization of volatiles and semivolatiles in SFE soybean oil and can be used to monitor the extraction and quality of the resultant oil.
Effects of water stress on the post‐harvest quality of two leafy vegetables, telfairia occidentalis and pterocarpus soyauxii during storage
Authors: Nwufo M I
Published: November 2006

The effect of water stress (excessive water loss) on the post‐harvest quality of two leafy vegetables, Telfairia occidentalis and Pterocarpus soyauxii, at ambient (30–35°C) and low temperature (10°C) was investigated in south‐eastern Nigeria. The effect of seal‐packaging the vegetables in polyethylene and paper bags on quality decline of the leafy vegetables was also monitored. Unsealed leaves of T occidentalis and P soyauxii rapidly lost water during storage at either ambient or low temperature. There were decreases in the chlorophyll, protein and ascorbic acid contents in the stressed leaves. Packaging of the leaves in polyethylene bags alleviated these losses. Sealing of the leaves in polyethylene bags also alleviated water stress.
Terminalia chebula seed oil—a minor source of 12‐hydroxyoctadec‐cis‐9‐enoic acid: Natural products as a source for the food and agricultural industries
Authors: Hosamani Kallappa M
Published: November 2006

Terminalia chebula, Retz seed oil belonging to the Combretaceae plant family, was found to contain 12‐hydroxyoctadec‐cis‐9‐enoic acid (20.5% of the total silylated methyl esters) previously hitherto unknown in the Terminalia genera. The identification and characterisation was based on thin‐layer chromatography, ga:‐liquid chromatography, and ultraviolet, infrared, nuclear magnetic resonance and mass spectral analysis, and chemical degradations.
Nitrate and nitrite in fresh vegetables from queensland
Authors: Lyons David J , Rayment George E , Nobbs Peter E , McCallum Leith E
Published: November 2006

Vegetables were collected near peak harvest from the main production regions in Queensland and were analysed for residues of nitrate and nitrite. A small sample of hydroponic produce was also included in the survey. Nitrite‐N from 1 to 4 mg kg‐1 was found only in dwarf beans and in lettuces. Levels of nitrate in potatoes, cabbages and beets were higher than those reported in other surveys and exceeded threshold limits set in one other country. The median nitrate‐N concentration measured in hydroponic lettuce (465 mg kg‐1 nitrate‐N) was more than twice the median concentration for field‐grown lettuce. Poor correlation between total N and nitrate in vegetables raises doubts about the use of total N alone as an indicator of N status.
Meat pigment determination by phase partitioning in triton x‐114 and oxidation with sodium nitrite
Authors: Garrido Dolores , Perez Ana , Alvaro Sánchez‐Ferrer
Published: November 2006

A method is described for determining the total pigment content of pork meat by oxidizing the pigments to metmyoglobin with sodium nitrite and using the non‐ionic detergent Triton X‐114. This detergent is used to solubilise and to increase the absorptivity of the myoglobin at the Soret band (A409). In addition, Triton X‐114 has the property of separating into two dear phases in equilibrium, one detergent‐rich and the other depleted, when the temperature is increased to 37°C. This phase separation removes all the non‐specific turbidity of the meat, which is one of the main problems encountered in determining pigment concentration and a source of inaccuracy. This method, called the Nit409/TX‐114 method, can be used in routine analysis for determing total pigment concentration in pork meat since it is accurate and rapid, and involves no toxic reagents or specialized equipment. The method can also be used to measure pigment in other meat types, even those with low pigment levels.
The effect of field drying on the non‐structural carbohydrate composition in vetch hay
Authors: Treviño Jesús , Centeno Carmen , Ortiz Luis , Caballero Rafael
Published: November 2006

Common vetch (Vicia sativa L) was harvested and allowed to dry in the open air. The composition of fresh forage in non‐structural carbohydrates varied markedly between years, the contents of sugars and starch in both leaves and stems being much higher in 1990‐91 than 1991‐92. Field drying produced a significant decrease in the amounts of these carbohydrates. The total losses of sugars and starch in hay, expressed as losses of dry matter, ranged from 28 to 15 g kg‐1, depending on the year.
Isolation and purification of three antifungal proteins from sorghum endosperm
Authors: Kumari Sunitha R , Chandrashekar A
Published: November 2006

Three proteins potently inhibitory to the growth of Fusarium moniliforme, the grain mould pathogen have been identified from sorghum endosperm, using aqueous extraction, gel filtration and ion‐exchange chromatography coupled with bioassay. The aqueous extract (Tris buffer, pH 6.8) of sorghum endosperm flour was separated into two fractions by passing through Sephadex G‐50. The void volume fraction, showing antifungal activity was further fractionated by ion‐exchange chromatography on SP Sephadex C‐50. The most potent fraction was that which bound to the SP Sephadex column at pH 6.0. A less potent fraction with an 18 kDa protein as major component was released on shifting the pH to 8.5. The bound fraction at pH 8.5 was a much more potent inhibitor of fungal growth than the unbound fraction; and it was composed of two major polypeptides with molecular weights of 26 and 30 kDa. All three polypeptides were separated on SDS‐PAGE gels, transferred onto Immobilon and tested for antifungal activity. The test showed that the 26 and 30 kDa proteins retained the antifungal activity even after electrotransfer. Antibodies raised against the electroeluted proteins were shown to abolish the antifungal activity of the endosperm extracts. These proteins appeared only in the endosperm of sorghum grains as revealed by dot immunobinding assay. The 26 and 30 kDa antifungal proteins were also present in pearl millet and maize, while the 18 kDa protein was found only in sorghum. Cross‐reactivity of antibodies with the aqueous extracts of wheat, rice and ragi was not seen.
A simple conceptual model for predicting the dissolution of phosphate rock in soils
Authors: Robinson J Stephen , Syers J Keith , Bolan Nanthi S
Published: November 2006

Laboratory experimental and literature data were integrated to develop a simple, conceptual model to describe and predict the dissolution of a reactive phosphate rock (Gafsa phosphate rock, GPR) in soils. The model showed that initial solution Ca concentration strongly influences the time required for a single application of GPR (at 30 kgP ha−1) to dissolve. The model predicts that all of the GPR will dissolve within a year of application in an unlimed, acid (pHw4.5) loam. However, if the soil has previously been limed to (pHw5.8, and contains permanent charge only, the model predicts that only about 50% of the GPR would have dissolved by the end of the second year after application. On the other hand, if a previously limed soil ((pHw5.8) contains variable‐charge components, the model predicts that virtually all of the GPR would have dissolved in this soil by the end of the second year after application. These results emphasise that, even in the presence of a high proton supply, solution Ca has an overriding influence on the dissolution of GPR. The faster rate of GPR dissolution in the limed soil with variable charge, compared to that in the limed soil with permanent charge only, demonstrates the ability of the variable‐charge component of soil to act as a sink for some of the lime‐derived Ca. According to the solubility product principle, this allows more GPR to dissolve. Because of the generally stronger buffering of soil for P than for Ca, a relatively large proportion of any P removed by leaching and plant uptake is buffered by the sorbed phase. Consequently, the influence of leaching and plant uptake on GPR dissolution is attributed primarily to the removal of the relatively less‐strongly buffered Ca.
α‐Amylase inhibitors in chick pea (cicer arietinum L)
Authors: Mulimani Veerappa H , Rudrappa G , Supriya D
Published: November 2006

The α‐amylase inhibitory activity of 28 varieties of chick pea (Cicer arietinum L) was determined, and KGT/GBS‐8 was found to have the greatest activity (81.4 units g−1). The inhibitor was heat labile and the inhibitory activity decreased during germination.
Breaking of structural dormancy in seeds of Tetrapleura tetraptera by Aspergillus niger
Authors: Ukpong Emaeyak N , Odoemena C S , Ekpo G
Published: November 2006

Aspergillus niger (strain UUF9202) significantly reduced the dormancy period and boosted aggregate germination percentage (AGP) in seeds of Tetrapleura tetraptera. A net reduction in mean germination time (MGT) to 12 days and an increase from 0 to 42% AGP were obtained in 32 days. The optimal spore inoculum of the fungus was 8.5 × 10≥10 ml−1 per 100 seeds in 96 h pregermination incubation. The potential of some physical factors in combination with this fungal concentration in enhancing AGP was evaluated. The treatments were as follows: (i) hot water scarification at 30°C, 50°C, 80°C and 100°C plus A niger; and (ii) nicking by decoating at either the micropylar or chalazal ends plus A niger. Micropylar scarification plus A niger gave the highest AGP (94%) followed by chalazal scarification plus A niger (86%) and hot water dip at 80°C + A niger (82%). The control seeds which were soaked in presterilised (by autoclaving at 121°C for 15 min) A niger spore suspension at 30°C gave zero germination.
Immunochemical identification of irradiated chicken eggs
Authors: Kume Tamikazu , Ishii Tetsuya , Matsuda Tsukasa
Published: November 2006

Immunoblotting analysis was used for the identification of irradiated chicken egg. Immunoreactivity of egg‐white proteins with specific antibodies was decreased by irradiation, but was still detectable even after irradiation at a higher dose (50 kGy). Sodium dodecyl sulphate‐polyacrylamine gel electrophoresis of irradiated egg white showed that the partial fragmentation of egg‐white proteins was induced by irradiation at 10 kGy. Furthermore, some antigenic peptide fragments with a molecular mass of 30 k Da or less were clearly detected in the irradiated egg white by immunoblotting analysis using antibodies to egg‐white proteins. Such fragments produced by irradiation were also detectable in egg irradiated at 2 kGy, the dose necessary to kill Salmonella, and in cooked egg (heated at 100°C for 15 min) after irradiation. These results proved that the immunoblotting would be a useful method for the identification of irradiated egg.
The relationships between gas production and chemical composition of 23 browses of the genus Sesbania
Authors: Nsahlai I V , Siaw Deka , Osuji P O
Published: November 2006

This study evaluated the differences in the gas produced by Sesbania accessions and related gas production to macro‐constituents and tannin content of the browse species. Fresh samples were incubated in triplicate (about 200 mg per syringe) in a medium prepared from sieved rumen liquor harvested from two rumen‐fistuiated cows fed native pasture hay ad libitum and 2.0 kg cottonseed cake per head per day. Sesbania species had similar rates of gas production but differed (P < 0.001) in the volume of gas produced. The ranking order for gas production was S grandiflora > S sesban > S keniensis > S goetzei. There was little variation in the gas production parameters within S grandiflora and S goetzei. But the variation was large within S sesban. Regression analysis showed that the rate of gas production was negatively affected (P < 0.025) by the lignin content of the browses, but the volume of gas produced was negatively related to the neutral detergent fibre, hemicellulose, lignin and insoluble proanthocyanidins content of browses. Ouster analysis showed a broad agreement between gas production constants, macro‐constituents and tannin contents in classifying accessions into high or low nutritive value groups.
Oxidation and transformation of elemental sulphur in soils
Authors: He Zhen‐Li , O'Donnell Anthony G , Wu Jinshui , Syers J Keith
Published: November 2006

The oxidation of35S‐S0(35S‐S0, sulphur flowers) added to four cultivated soils was well described using first‐order kinetics. The half‐life (tl/2) of35S‐S0ranged from 12 days in a paddy soil to 176 days in an Ultisol. During the early phase of oxidation, a large proportion of the oxidised S was incorporated into organic fractions. After the first week any additional35S‐S0oxidised remained primarily as SO‐S in most of the test soils. The amount of KH2PO4‐ extractable35S‐SO‐S as a percentage of total oxidised35S‐S was at a maximum when approximately half of the added35S‐S0was oxidised. By the end of the 56‐day incubation period, with the exception of the Ultisol, 54–70% of the oxidised35S‐S in the test soils was present as35S‐SO‐S. The remaining oxidised S is presumed to have been converted into organic matter fractions. This35S‐organic‐S could be fractionated into the 0.1 M KH2PO4‐extractable organic‐ S (5–13% of total oxidised35S‐S) and the 0.01 M NaOH‐extractable organic‐S (14–23% of total oxidised35S‐S). With the exception of the Ultisol where the undetermined organic S was about 36%, the amounts of unaccounted for S (not directly measured), in all soils were very small (typically less than 4%).
Equilibrium moisture characteristics of dehydrated food constituents as studied by a modified inverse gas chromatographic method
Authors: Lagoudaki Maria , Demertzis Panagiotis G
Published: November 2006

Computerised inverse gas chromatography was used to study the combined effects of moisture and temperature on the water sorption of potato starch, egg albumin and wheat gluten. A moisture increase resulted in typical BET‐II sorption isotherms. The water sorption isotherms of the three food constituents determined at 22, 30, 37 and 45°C showed that water sorption is favoured at low temperatures. A comparison between the computerised inverse gas chromatographic and the static gravimetric methods at 30°C showed that the former was faster and that the sorption isotherms of the two methods correlated well. BET, GAB, Freundlich, Chung‐Pfost, Smith and ‘Local’ isotherm models were tested to fit the data. Goodness of fit, standard deviation and applicable range of water activity (aw) indicated that GAB and ‘Local’ isotherm models could explain the data well over a wide aw range to 0.80. The heats of sorption of the three substrates were also calculated.
Quality of dried apricots: Effect of storage temperature, light and SO2 content
Authors: Rosselló Carmen , Mulet Antonio , Simal Susana , Torres Antonia , Cañellas Jaime
Published: November 2006

Effects of storage temperature, light and SO2 content on the quality of dehydrated apricots (moisture content of c 180 g water kg−1) were investigated. The samples, with SO2 contents, 300 and 1400 mg kg−1, were stored for 9 months at 4, 11°C and at room temperature (20–25°C). Colour, browning, texture, soluble sugars and protein content were periodically determined. In samples with high SO2 content stored at different temperatures and samples with low SO2 which were refrigerated, the quality remained almost constant, meeting market requirements at the end of 9 months storage. Non‐refrigerated samples, with a low SO2 content suffered intense browning reactions during storage, with losses of 15–26 units for L*, a* and b, as well as losses in soluble sugars (150 g kg−1). Protein could not be detected at the end of the storage and furfural content was high (18–23 mg kg−l). The presence or absence of light did not appear to influence the quality of the product.
Analysis of proanthocyanidins in coffee pulp
Authors: De Colmenares Nélida González , Ramírez‐Martínez Jose R , Aldana Jose O , Clifford Michael N
Published: November 2006

Data are presented for the condensed tannins content of pulp prepared immediately from die cherries of three cultivars of freshly harvested coffee beans, and for the pulp after drying. The data have been interpreted with reference to purified quebracho profisetinidins (3.13–6.17% on a dry basis (db)) and to the E% values of the anthocyanin pigments formed by oxidative depolymerisation (0.60–1.19% db). Pulp from a yellow‐fruited cultivar was significantly richer (P < 0.001) than pulp from the associated red‐fruited cultivar. In contrast to previous reports the presence has been established of condensed tannin in the pulp at the time the cherry was harvested although an increase was observed on subsequent drying. Prodelphinidins could not be detected, but the presence of procyanidins was confirmed. Analysis of procyanidin dimer‐rich and procyanidin oligomer‐rich fractions suggested that while dimers dominate in undried pulp, dimers may be converted to oligomers during drying. Measurements of haemoglobin precipitation (relative astringency) were generally consistent with increased tannin content/polymerisation after drying but little interaction with methylene blue was detectable in any sample.
The nutritional value of roselle seed meal in laying hen diets
Authors: Backeit Mohammed H , El Zubeir El Fadil A , Jubarah Salah K
Published: November 2006

The effects of feeding mechanically extracted roselle seed meal (RSM) to laying hens at dietary levels up to 200 g kg−1 were studied over a 14‐week period. RSM contains 491.1 g crude protein, 59 g ether extract, 169.6 g crude fibre, 113.5 g ash, 6.8 g calcium, 6.6 g total phosphorus and 0.6 g magnesium kg−1. From chemical analyses the metabolisable energy content of RSM would be expected to be 10.07 MJ kg−1 but a high value (11.63 MJ kg−1) was obtained for true metabolisable energy using chick growth assay. As the inclusion rate of RSM increased rate of lay, feed intake and egg weight were increased (P < 0.01). The dietary treatments had no significant effects on feed conversion ratio, mortality, shell thickness, albumen height, and yolk colour.
Relationship between rate of post mortem pH fall and ageing of Longissimus muscle in pietrain pigs
Authors: Fernandez X , Culioli J , Gueblez R
Published: November 2006

Twenty‐six pietrain pigs exhibiting wide variability in pH45 (pH value 45 min post mortem) values were used to assess the mechanical behaviour of cooked and raw Longissimus muscle at 24 h and 8 days post mortem. Rheological behaviour was studied in compression under strain conditions which allow specific determination of myofibrillar resistance. The muscles were divided into three groups on the basis of pH45 values: (Severe pale, soft and exudative (PSE), pH45 = 5.49 ± 0.03 (n = 9); PSE pH45 = 5.78 ± 0.04 (n = 10); Normal, pH45 = 6.35 ± 0.05 (n = 7). The three groups did not differ significantly for ultimate pH (pHu = 5.57 ± 0.02 for the 26 muscles). A lower mechanical resistance of raw samples was found in the Normal group, regardless of the time post mortem. Although this difference was not significant, a significant relationship was found between this trait and pH45 at both times post mortem (r = −0.43, P < 0.05, at 24 h and r = −0.44, P < 0.05, at 8 days post mortem). However, no significant effect of pH45 was found on the mechanical resistance of cooked muscles. The relative decrease in myofibrillar strength after an 8‐day ageing period was not affected by pH45 but this was due to the fact that the three groups exhibited different starting points. Mechanical resistance of raw and cooked muscles at 24 h post mortem were significantly related to pHu (r = −0.55, P < 0.01, and r = −0.49, P < 0.05, respectively). The present results show that after an 8‐day ageing period, PSE muscles are not fully aged.
Quality changes in HTST processing of rice parboiling
Authors: Pillaiyar P , Singaravadivel K , Desikachar H S R
Published: November 2006

Paddy soaked to saturation level, when treated at a high temperature for a short time in a mechanical sand roaster is parboiled and dried in a single pass of 47 s duration. The extent of drying depends on the sand temperature. The sand temperature is critical as it decides the associated quality changes in the milled rice. Even at a sand temperature of 125°C, paddy could fully be parboiled but with mild effect. The parboiling became severe at high temperatures. Roasting the soaked paddy at 250°C, reduced the cooking time of the resultant milled rice. A sand temperature of 125–150°C was considered suitable for producing normal parboiled rice by this technique.
Nonprotein nitrogen content of defatted jojoba meals
Authors: Wolf Walter J , Schaer Mardell L , Abbott Thomas P
Published: November 2006

Extraction of defatted jojoba meals with 0–5 M triehloroacetic acid solutions revealed a minimum solubility of nitrogenous compounds in the range of 0.5–2 M. This minimum was assumed to correspond to the nonprotein nitrogen (NPN) fraction. Trichloroacetic acid concentrations of 0.8–1.0 M were found to be optimal for NPN determination. NPN values for laboratory‐prepared meals ranged from 21 to 29% of the total nitrogen for undecorticated (with seed coat) meals and from 21 to 30% for decorticated (without seed coat) meals. Commercial presscakes and presscake fines ranged from 15 to 20% of total nitrogen as NPN. These lower values apparently reflect heat treatments received by the presscakes during commercial expelling of the jojoba liquid wax esters, In aqueous dispersions of unheated jojoba meals, nitrogenous compounds exhibited a minimum solubility of 23–45% of total nitrogen at pH 3–4, the apparent isoelectric region of the storage proteins. In some meals NPN comprised up to 100% of the nitrogen soluble at this minimum; thus, low yields of recoverable meal nitrogen in the form of protein isolates are predicted. The NPN fraction was characterized by amino acid analysis and gel electrophoresis and found to contain free amino adds, peptides, and polypeptides of 6–10 kDa. Simmondsin and its derivatives are estimated to make up about one‐third of the NPN.
Hydrolysis of galactooligosaccharides by commercial preparations of α‐galactosidase and β‐fruetofuranosidase: Potential for use as dietary additives
Authors: Slominski Bogdan A
Published: November 2006

In vitro and in vivo studies were conducted with six commercial enzyme preparations (SP249, Energex, Rohament CW, Novozyme 230 and crude α ‐galactosidase) to determine their effectiveness in hydrolysing galactooligosaccharides from soya bean and canola meal in the gastrointestinal tract of poultry. The use of the enzyme invertase to enhance galactoside hydrolysis was also studied. A wide range of α ‐galactosidase activity was observed in vitro, with crude α‐galactosidase from Mortirella vinacea and Novozyme 230 preparation showing the highest activity values of 4.3 and 1.5 nkat mg−1, respectively. All preparations with the exception of crude α‐galactosidase showed invertase activity which is known to convert raffinose and stachyose to the corresponding di‐and trisaccharide, melibiose and manninotriose. Although the activity of invertase was highest on sucrose, the Novozyme 230 preparation showed activity values of 4.2 and 2.3 nkat mg−1 toward raffinose and stachyose substrates, respectively. De novo synthesis of raffinose was observed when soya bean meal, canola meal or pure sucrose and galactose were incubated with certain enzyme preparations (ie Energex). In general, preparations possessing hydrolytic activity towards galactooligosaccharides showed very little synthesis of raffinose while preparations capable of generating raffinose were very weak in the hydrolysis of galactooligosaccharides. The best result in terms of galactooligosaccharide in vitro hydrolysis of canola and soya bean meal was obtained with a combination of α‐galactosidase and invertase. In the in vivo study with caecectomised hens, hydrolysis of galactooligosaccharides averaged 88% when crude α‐galactosidase (2 g kg−1) and invertase (1 g kg−1) were added to laying, hen diet containing 200 g soya bean meal per kilogram. A problem identified in the current study was that minerals such as calcium phosphate and calcium carbonate common in poultry diets inhibit the hydrolysis activity of α‐galactosidase, indicating that high levels of activity would be required to yield a response in practical poultry feeding.
Chemical reactions of benzyl isothiocyanate with egg‐white protein fractions
Authors: Kroll Juergen , Noack Jutta , Rawel Harshadrai , Kroeck Regina , Proll Juergen
Published: November 2006

Glucosinolates and their highly reactive breakdown products (mainly isothiocyanates, ITC) belong to the group of very important natural toxicants. This paper describes the interactions of benzyl‐ITC with the egg‐white protein fractions ovalbumin, conalbumin, ovomucoid, and lysozyme and the resulting formation of protein‐ITC derivatives. Benzyl‐ITC reacts with the amino groups of the proteins, forming thiourea derivatives. Such reactions are characterised by decreases in the levels of free amino groups and available lysine. Other reaction sites of benzyl‐ITC are sulphydryi side‐chains of proteins, the results being formation of dithiocarbamate esters. This in turn results in a decrease of SH‐groups due to carbon disulphide being released from their esters. The present study describes the reactions of benzyl‐ITC with amino groups and sulphydryl side‐chains, and the subsequent decrease of lysine and crysteine after derivation. Changes in the behaviour of ITC‐derived egg‐white protein fractions were analysed by SDS‐PAGE and RP‐HPLC.
Flavonoids from the roots of two Rhynchosia species used in the preparation of a Zambian beverage
Authors: Zulu Rodah M , Grayer Renée J , Ingham John L , Harborne Jeffrey B , Eagles John
Published: November 2006

High concentrations of flavonoids were found in the roots of Rhynchosia insignis and R heterophylla used for the preparation of the popular Zambian munkoyo beverage. The major flavonoids were isolated and identified by means of fast atom bombardment mass spectroscopy and co‐chromatography with authentic standards as vicenin‐2, schaftoside, isoschaftoside and an isovitexin derivative (in both species) and, additionally, vitexin, isovitexin and a violanthin‐type compound in R heterophylla. As these compounds are yellow to orange‐yellow in the concentrations found in the roots, they are likely to be responsible for the yellow coloration of the beverage before fermentation.
The glutenin fraction of wheat protein: The importance of genetic background on its quantity and quality
Authors: Pritchard P E , Brock C J
Published: November 2006

The influence of high‐molecular‐weight glutenin subunits on the properties of the gel‐protein fraction of glutenin proteins in wheat was determined on 20 varieties grown in the 1989 UK Recommended List trials. Both the presence of subunit 1 (chromosome 1A) and the 1B/1R rye translocation were shown to influence gel‐protein weight and breakdown rate during mixing. The gel‐protein tests were correlated with CBP (Chorleywood Bread Process) loaf volume, but they did not add anything to the correlation between Glu‐1 score and loaf volume. Both gel‐protein tests indicated that phenotypic variation could be almost as large as genotypic variation. Breakdown rate was able to detect the abnormal properties of Pastiche (weak) and Fresco (extra‐strong) that were not observed using established quality tests such as the sodium dodecylsulphate sedimentation volume.
Effect of high temperature on condensed tannin accumulation in leaf tissues of big trefoil (Lotus uliginosus Schkuhr)
Authors: Lees Garry L , Hinks Christopher F , Suttill Neil H
Published: November 2006

Plants from three clones of big trefoil (Lotus uliginosus Schkuhr) having low, medium and high concentrations of tannin in their leaves were subjected to growing conditions with normal (20°C) and high (30°C) temperature regimes. Plants were tested every 3 weeks for foliar condensed tannin content using the vanillin‐HCl and the butanol‐HCl assays. Plants from clones growing under high temperatures matured more quickly and by 14 days had condensed tannin levels substantially greater than plants from the same clones grown under normal temperatures. Clones remained consistent with respect to their parental tannin levels throughout two trials. Leaves from high‐temperature clones suffering additional nutrient stress symptoms had very low levels of foliar condensed tannins and cross‐sections of chlorotic leaves revealed an absence of large tannin vacuoles. It is concluded that high‐temperature stress can induce the formation of additional condensed tannin in the leaves of this species.
Breakdown of amylomaize starch granules in gnotobiotic rats associated with four bacterial strains isolated from conventional rat microflora
Authors: Deiahaye Emperatriz Pacheco , Bouchet Brigitte , Andrieux Claude , Raibaud Paul , Szylit Odette , Gallant Daniel J
Published: November 2006

Balance studies in germ‐free (GF) and conventional (CV) rats have shown that in‐vivo breakdown of amylomaize starch depends on endogenous and bacterial enzymes. In GF rats, one‐third of amylomaize starch is resistant to endogeneous digestion, whereas in CV rats starch is totally degraded, In order to study the contribution of endogenous and bacterial enzymes, the in‐vivo breakdown of amylomaize starch was compared in GF and in gnotobiotic rate associated with bacterial strains isolated from the conventional rat microflora. These bacteria were (i) a non‐amylolytic Peptostreptococcus (GNP rats),(ii) an amylolytic strain of Eubacterium able to hydrolyse resistant starch (GNE rats), and (iii) an association of Eubacterium with three other bacterial strains (Veillonella, Enterococcus and Peptostreptococcus) able to ferment the products of starch hydrolysis (GNT rats). Various studies were performed to assess the starch breakdown in the caecal contents: balance studies, light and electron microscopy and analyses of bacterial metabolites. The results show that in GNP as in GF rate, around 65% of amylomaize starch was resistant to digestion. Digestive utilization of starch was significantly improved in GNE rats (from 68 to 92%) and was further enhanced to 97% in GNT rats. The increase in starch degradation in the caecum of rats was related to a higher amylase activity and led to an increase in production of bacterial metabolites, and to a change in the proportions of short‐chain fatty acids, lactic acid and succinic acid, infrastructure study of the starch in the caecal contents showed a progressive granule hydrolysis in the order GF, GNE and GNT rats: (i) an endocorrosion of the central part of the starch granules in GF rats, (ii) a peripheral digestion with bacteria penetrating the granules in GNE rats, and (iii) a more pronounced hydrolysis in the caecum of GNT rats where the outer part of the granules were almost entirely hydro‐lysed. These results suggest that starch breakdown in the hindgut is not only due to amylolytic bacteria but also to the contribution of other glycolytic strains able to utilize the products of starch hydrolysis.
Statistical process analysis in broiler feed formulation
Authors: Alti Müsamettin , Özilgen Mustafa
Published: November 2006

Statistical analysis of broiler feed production was done with data obtained in an industrial plant in an attempt to characterise the causes of variations in feed composition. Analysis of the experimental data has shown that the feed conversion ratio (FCR) for broilers was between 1.8 and 2.5. This large range of observations were thought to be caused by the wide range of variations in the composition of the feeds. The major factor contributing to the variance of the feed compositions was the variance of the raw materials. It was found that the proteins and moisture were distributed normally in most raw materials and feeds. Water molecules can diffuse in the raw materials and the feeds to make the whole batch uniform. On the other hand, the protein containing fractions tend to segregate due to density differences. Therefore, the moisture content of the raw materials tend to vary in a smaller range than those of the proteins. Mixing the feeds for three minutes or longer was sufficient to achieve suitable homogeneity, but controlling the range of the individual raw materials is recommended for further improvement of the process capability indices.
Effects of mincing and frozen storage on functional properties of ray muscle (Raja clavata)
Authors: Pastoriza Laura , Sampedro Gabriel , Herrera Juan J
Published: November 2006

This is a study on changes in protein functionality of rayfish muscle as a consequence of frozen storage in order to achieve a deeper knowledge of the effects of different degrees of cellular disruption (whole, 8 and 12 mm minced muscle) and the frozen storage temperature (−18°C and −40°C). Significant differences (P < 0.05) were found in some functional properties, with significant decreases in salt‐extractable protein and apparent viscosity, and significant increases in emulsifying capacity and water‐binding capacity after 1 year of frozen storage at 18°C. Practically no changes were observed after 2 years of frozen storage at −40°C. The greatest modifications were found in the 8 mm minced fish sample. Viscosity was the parameter that best showed the changes in whole and minced muscle stored at both temperatures. Apparent viscosity, emulsifying capacity and water‐binding capacity had a good correlation with salt‐extractable protein.
Does the method of drying a hydrated non‐starch polysaccharide affect in‐vitro analyses to predict physiological function?
Authors: Stevenson Agnes , Buchanan Callum J , Eastwood Martin A
Published: November 2006

It is possible to anticipate the action of dietary non‐starch polysaccharides (NSP) using in‐vitro methods. The mode of isolation of hydrated polysaccharide suspensions previous to analysis may influence the result. A commercial hydrated polysaccharide (Frucht and Faser) was isolated using four different processes and used in functional in‐vitro studies. Ethanol precipitated and heat‐dried materials had a reduced soluble NSP content. The particle size of the heat‐dried preparation differed. Heat‐drying resulted in reduced glucose immobilisation. Following fermentations there was enhanced production of total short‐chain fatty acids by heat‐dried and freeze‐dried preparations. In the description of dietary NSP the mode of isolation must be identified to allow comparison of results.
Glycoalkaloid concentration of potato tubers following continuous illumination
Authors: Percival Glynn , Dixon Geoffrey , Sword Alastair
Published: November 2006

The total glycoalkaloid concentration of dormant (non‐sprouted) and sprouted potato tubers cv Pentland Hawk was measured following 13 days continuous illumination (250 μmol m−2 s−2 photosynthetically active radiation) using high‐performance liquid chromatography. Comparisons were made of the influence of three sources of illumination: high‐pressure mercury, high‐pressure sodium and fluorescent tube type warm white. Glycoalkaloid concentrations in both dormant and sprouted tubers increased over 13 days illumination regardless of the form of illumination used. Glycoalkaloid concentrations accumulated with time in dormant and sprouted tubers exposed to sodium and fluorescent light but fluctuated in those exposed to mercury light. Dormant tubers were more sensitive to illumination than sprouted tubers regardless of light souce. Fluorescent light was associated with maximum glycoalkaloid synthesis in dormant tubers; while sodium light enhanced glycoalkaloid synthesis in sprouted tubers to the greatest extent. Mercury light weakly elicited glycoalkaloid synthesis in both sets of tubers. Exposure of dormant tubers to continuous light altered the ratio of α‐chaconine to α‐solanine irrespective of illumination source.
The effects of freezing, meat pH and storage temperature on the formation of white film and tyrosine crystals in dry‐cured hams
Authors: Arnau Jacint , Gou Pere , Guerrero Luis
Published: November 2006

The effects of freezing, meat pH and storage temperature on the formation of white film and tyrosine crystals in dry‐cured hams were evaluated in three experiments. Freezing of green hams did not affect the tyrosine concentration but increased the formation of tyrosine crystals and decreased white film intensity. The incidence of hams with tyrosine crystals and white film was lower in those with high pH meat. White film increased as the storage temperature decreased and was not found to be present around the tyrosine crystals.
In‐vitro studies on the effect of polyphenol oxidase and peroxidase on the formation of polyphenolic black tea constituents
Authors: Finger Andreas
Published: November 2006

Flavanols (catechins and gallocatechins) isolated from green tea leaves (Camellia sinensis) (L) O Kuntze) were treated in vitro with polyphenol oxidase, peroxidase and a combination of both. The flavanol levels and those of the products formed were monitored by reversed‐phase high‐performance liquid chromatography (HPLC using spectrophotometric detection at 280 and 380 nm. Flavanols and theaflavins were quantified, whilst integrated peak areas are given for the remaining compounds. After fermentation in the presence of polyphenol oxidase higher levels of theaflavins and resolved thearubigins were obtained, whilst peroxidase produced higher amounts of chromatographically unresolved thearubigins of higher molecular weight, observed as a rise in the HPLC baseline, in the presence of peroxidase a significant decrease in the levels of all flavonol glycosides was observed, whilst in the presence of polyphenol oxidase only myricetin glycoside levels decreased.
Alkaloid, α‐galactoside and phytic acid changes in germinating lupin seeds
Authors: de la Cuadra Celia , Muzquiz Mercedes , Burbano Carmen , Ayet Gemma , Calvo Rosa , Osagie Anthony , Cuadrado Carmen
Published: November 2006

The aim of this work was to investigate the effect of germination on the concentrations of some antinutritional factors in Lupinus albus and L luteus seeds. The seeds were germinated for 24, 48, 72 and 96 h. The alkaloid, phytic acid and α‐galactoside changes were monitored by capillary gas chromatography and HPLC techniques. The rate of seed germination for both lupin species was lower in total darkness than when 8 h of light was supplied. The total alkaloid level was not significantly altered by 96 h germination of the seeds. Albine, α‐isolupanine, lupanine, multiflorine and 13‐OH‐lupanine were identified in L albus whereas lupinine, sparteine and lupanine were identified in L luteus. α‐galactoside levels were drastically reduced during germination of lupin seeds and stachyose was the predominant sugar in both species. The major inositol phosphate (IP6) appeared to be degraded to lower inositol phosphates during lupin seed germination. It is concluded that germination is a useful process to improve the nutritional value of lupin seeds.
The use of sodium carbonates to improve textural properties of cod minces
Authors: Kołakowski Edward , Kołakowska Anna , Lachowicz Kazimierz , Bortnowska GrażYna , Wianecki Marek
Published: November 2006

Effects of sodium carbonates on the textural properties of fresh and frozen cod mince were evaluated. Na2CO3 and NaHCO3 (optimal does of <5 and 3 g kg−1, respectively) were found to markedly reduce weight losses after steaming (more than 25%) and to significantly improve texture and palatability despite the fact that extractability of myofibrillar protein was reduced.
Changes in protease inhibitory activity from pigeon pea (Cajanus cajan (L) millsp) during seed development and germination
Authors: Godbole Sangeeta A , Krishna Thirumalai G , Bhatia Chittaranjan R
Published: November 2006

The protease inhibitors from seeds of pigeon pea (Cajanus cajan (L) Millsp) have been studied for their physiological role. During seed development the inhibitor was detected even as early as 7 days after flowering (DAF). But the maximum amount accumulated between 14 and 28 DAF. During this period the seed accumulates a major portion of its proteins. During germination the inhibitor activity decreases from 6 days after germination up to 10 days. Accompanying this change there is a marked decrease in the amount of cotyledonary proteins. The inhibitor does not appear to be associated with the protein bodies. The endogenous protease from the seeds was identified as a serine protease and was not inhibited by the inhibitor. The inhibitor was earlier shown to be specific towards mammalian serine protease. Although the inhibitor did not inhibit the protease from Helicoverpa armigera larva as efficiently as soyabean trypsin inhibitor a defence role for the inhibitors cannot be ruled out.
Influence of selected process variables on the elimination of cyanide from cassava
Authors: Jones Deborah M , Trim David S , Bainbridge Zoe A , French Lisa
Published: November 2006

The effects of selected methods of size reduction, holding periods and drying on elimination of cyanide from cassava roots of variety MCol 1684 were investigated. Drying at 50°C eliminated approximately 50% of the total cyanide from mechanically prepared chips, and 25% from manually prepared chips. Mechanical chipping and drying at 50°C eliminated 65% of the total cyanide from small chips and 47% from large chips. Mincing of whole roots completely degraded the glucoside, and rasping and mechanical chipping degraded 70–80% and 30% of the initial glucoside respectively. The results indicate that the method of size reduction and particle size control the rate of glucoside degradation, and that the drying rate limits the quantity of glucosidic cyanide eliminated. The results are compared with those of other researchers.
Formation of volatile pyrrole products from epoxyalkenal/protein reactions
Authors: Zamora Rosario , Ríos José J , Hidalgo Francisco J
Published: November 2006

The production of volatile compounds in the reaction of the lipid peroxidation product (E)‐4,5‐epoxy‐(E)‐2‐heptenal with lysine or bovine serum albumin was studied in order to characterise alternative mechanisms for production of volatile pyrrole derivatives in foods. A mixture of the lipid and the ammo acid or the protein was stirred overnight at 31°C and the volatiles formed were collected using a Tenax TA trap. Several aldehydes, ketones, alkylfurans, alkyl‐ and acyl‐pyrroles, and alkylpyridines were identified by GC/MS. Formation of pyrrole derivatives in these reactions suggested the existence of alternative mechanisms for production of these flavour‐associated compounds, previously considered to be formed mainly via Maillard reactions. This new route does not need the presence of sugars, and might contribute significantly to volatile pyrrole production in foods under conditions unfavourable for classic Maillard reactions.
Flux pattern and fouling of membranes during ultrafiltration of some dairy products
Authors: Rao H G Ramachandra , Grandison A S , Lewis M J
Published: November 2006

The flux pattern of milk (whole milk, skimmed milk and buttermilk) showed a distinct contrast to whey (sweet whey and acid casein whey) systems during ultrafiltration (UF) at constant composition. For milk systems, the initial flux was lower than for whey systems, but the flux stabilised within a few minutes of operation. However, for both acid and sweet whey, the flux continued to fall with time for nearly 1 h. The fouling coefficient (FC) for buttermilk was 0.6 after 5 min, rising to 0.68 after 60 min. During this time flux did not decline, suggesting that concentration polarisation (CP), rather than fouling, was controlling the flux rate. In contrast, the FC for whey was 0.5 after 5 min with a progressive rise over the next 55 min, but the flux also fell throughout this period suggesting that flux was controlled by fouling rather than CP. The higher concentration of protein in milk systems appeared to be responsible for CP, rather than fouling, being the controlling mechanism.