bluuebunny/crossref_metadata_2025 huggingface dataset:
The relation between yield and protein in cereal grain
Authors: Simmonds Norman W
Published: November 2006

An analysis of published data on genetic relations between dry grain yields (y, t ha−1) and protein content [p, protein as a fraction (g g−1) of dry grain] of cereals is presented. In all, 106 usable regressions of y on p across geneotypes were assembled. The long‐recognised negative relation between yield and protein concentration was fully substantiated. There is a strong positive relation between grain yield and protein yield. The linear regression coefficient of yield on protein concentration is related to yield, with slope about −15. This relation holds approximately over all cereals. The data can be used to estimate a characteristic parameter described by C = dy/d(yp) = ∼ 15–25 at the mean of each experiment. The relationship is surprisingly consistent but no simple physiological interpretation is available. In discussion, the high C, the impact of strong negative regressions of y on p for breeding strategies, the fact that protein yield increases with gross grain yield but at falling p and certain socio‐economic consequences are emphasized. An acute need for orderly reporting of experimental data is also emphasised; the existing literature is chaotic as to units, moisture contents and conversion factors.
Silk maysin content and resistance of commercial corn [maize] hybrids to kernel contamination by aflatoxin
Authors: Widstrom Neil W , Snook Maurice E , Wilson David M , Cleveland Thomas E , McMillan William W.
Published: November 2006

Several phenols and related compounds have been shown to have detrimental effects on insects while others have antibiotic activity against fungi which attack higher plants. Insects have also been implicated as contributors to preharvest contamination of corn [maize], Zea mays L, by aflatoxin. The objectives, therefore, were to determine (a) if commercial corn hybrids vary in their silk maysin content and aflatoxin contamination of the grain, and (b) if grain aflatoxin contamination is correlated with maysin and related compounds. During 4 years of testing, 16 corn hybrids varied significantly for silk maysin content and grain aflatoxin contamination. Based on correlations, grain aflatoxin content of the hybrids tested was not significantly associated with maysin, chlorogenic acid, and 3′‐methoxymaysin contents. It was concluded that other untested phenolic compounds in the category of compounds analyzed in the present study could be involved in resistance to aflatoxin formation, and that other classes of compounds should also now be assessed to locate major chemical resistance components.
Red clover extracts inhibit legume proteolysis
Authors: Jones Beth A , Muck Richard E , Hatfleld Ronald D
Published: November 2006

Unwilted red clover and alfalfa herbage were hand‐chopped, inoculated, ensiled into laboratory silos and opened after 0, 1, 3 and 7 days. Proteolysis was 40% lower with the red clover silage than alfalfa silage after 7 days of ensiling. The lower extent of proteolysis with the red clover silages could not be explained by differences in dry matter content, pH decline nor final pH of the silage. It was determined that red clover has a buffer soluble protein that could inhibit proteolysis in red clover and alfalfa. The soluble protein is possibly a polyphenol oxidase.
Relationship between laser‐induced fluorescence intensity and crude palm oil quality
Authors: Tan Yew Ai , Chong Chiew Let , Low Kum Sang
Published: November 2006

Crude palm oil quality is an important consideration in the production of refined palm oil of consistent high quality. The quality of crude palm oil is determined by the analysis of oxidative and hydrolytic parameters such as peroxide value, anis dine value, free fatty acid content and moisture and impurities, all very time consuming and counter‐productive for both crude palm oil mills and refineries to carry out. This study shows that laser‐induced fluorescence (LIF) analysis can be used as an alternative to analysing all the common oxidative and hydrolytic parameters mentioned. LIF at 673 nm was indicative of the oxidative quality of crude palm oil. There was also positive correlation between fluorescence intensity and the carotene and the deterioration of bleach ability index of crude palm oil, and the Rancimat induction time of the final refined product.
Biodegradation of plant cell walls, wall carbohydrates, and wall aromatics in wheat grown in ambient or enriched CO2 concentrations
Authors: Akin Danny E , Rigsby Luanne L , Gamble Gary R , Morrison W Herbert , Kimball Bruce A , Pinter Paul J , Wall Gary W , Garcia Richard L , Lamorte Robert L
Published: November 2006

Mature internodes from wheat (Triticum aestivum L) grown in control (ambient at c 370 μnol mol−1) or enriched (to 550 μmol mol−1) concentrations of atmospheric CO2 in the free‐air CO2 enrichment (FACE) system were analyzed for potential changes in biodegradation of constituents due to predicted increases in atmospheric levels of CO2. The first internodes below the grain were incubated with the lignocellulose‐degrading white rot fungus, Phanerochaete chrysosporium K‐3, or incubated without microorganisms. Plant samples were then analyzed for dry weight loss, disposition of specific cell types to biodegradation using electron microscopy, carbohydrates and lignin using solid state NMR spectroscopy, and ester‐and ether‐linked aromatics using gas chromatography. Phanerochaete chrysosporium extensively degraded stems cells (c 75%) and both carbohydrate and aromatic portions of the wheat stems; proportionately more carbohydrates were removed by the fungus from the stems. Enriched CO2 did not affect the chemical composition of wheat stems or the biodegradation by P chrysosporium of plant cell walls or wall components for the most part. Data from various methods all indicated that enriched CO2 did not substantially alter the biodegradation of wheat cell wall internodes or wall components. Evidence was not found for an influence on C cycling due to CO2 concentrations in this study.
Trypsin inhibitory activity of raw soya bean after incubation with rumen fluid
Authors: Susmel Piero , Spanghero Mauro , Marchetti Stefano , Moscardini Stefano
Published: November 2006

Four soya bean (Glycine max Merr) inbreds, two of which (Williams 82 and Amsoy 71) capable of synthesising the Kunitz trypsin inhibitor (high trypsin inhibitory activity (TIA)) and two (L81–4590 and L83–4387), nearly isogenic to the former but lacking this particular function (low TIA) were used. In‐vitro trials were performed to evaluate the residual TIA of flours incubated with runem fluid and the possible effect of proteinase inhibitors on rumen microbial fermentation, estimated by gas production. Only a slow fall in TIA was observed after short incubation times (5–10% at 2 h and 10–18% at 6 h), but after this period the rate of decline of TIA accelerated to give residual TIA of about 50% after 12 h and undetectable values after 48 h. Significant differences between genetic backgrounds were observed only at 2 h, when the Williams 82 background had a faster initial loss of TIA (89.1 versus 97.5% of the original activity, P < 0.01). Different patterns of TIA degradation were observed according to the presence/absence of the Kunitz inhibitor: inbreds lacking the Kunitz inhibitor initially had a higher residual TIA (95.9 versus 90.7%, P < 0.01) while at 12 and 24 h the residual TIA was considerably lower with respect to the other inbreds (45.4 versus 60.8 and 10.7 versus 20.4, respectively, P < 0.01). Gas production after 2 and 6 h of incubation was similar across treatments, whereas slightly but consistently more (P < 0.05) gas was produced at longer incubation times for inbreds lacking the Kunitz inhibitor. The results indicated that the proteinase inhibitors contained in raw soya bean are degraded at a much slower rate than previous nylon bag studies have suggested and that the presence of the Kunitz inhibitor leads to a higher residual TIA after rumen degradation and slightly lower microbial gas production.
Creating typical jagged force‐deformation relationships from the irregular and irreproducible compression data of crunchy foods
Authors: Ulbricht Diane , Normand Mark D , Peleg Micha
Published: November 2006

The irregular jagged force‐deformation relationships of two snacks stored at nine levels of relative humidity were used to create typical‐averaged relationships by a special mathematical procedure developed on the basis of the statistical properties of random sequences. The typical force‐deformation relationships so created were practically indistinguishable from the original experimental ones from which they were derived. In principle, they can be used to identify conditions where textural changes take place and to establish criteria for textual classification of samples by visual comparison.
Microbial and sensory quality of vegetables for soup packaged in different atmospheres
Authors: Manzano Marisa , Citterio Barbara , Maifreni Michela , Paganessi Mario , Comi Giuseppe
Published: November 2006

Fresh prepacked vegetables for soup have become very popular on the Italian market, since they are already peeled, cut, washed and ready‐to‐use. The packaging and the modified atmosphere can prolong their shelf‐life and maintain their hygienic, physicochemical and sensory characteristics during storage at + 4°C. The hygienic and sensory quality was evaluated by analysing microbial growth and atmosphere composition at the moment of packaging and at the end or the shelf‐life of vegetables prepacked in air on under modified atmospheres, and by determining the browning or blackening of parsley and the loss of carrot exudates. A large number of different groups of microorganisms was found in raw vegetables. In spite of this high starting concentration of microbial flora, the prepackaging systems investigated did not seem to significantly influence their growth during vegetable storage at +4°C. No pathogenic microorganisms were isolated from the prepackaged vegetables. The hygienic quality was similar in all packaging systems used. However, the vegetables packaged in perforated. film kept their sensory characteristics better than those packaged in air or under a modified atmosphere.
Sensory evaluation of bitterness and astringency of 3R(−)‐epicatechin and 3S(+)‐catechin
Authors: Thorngate J H , Noble A C
Published: November 2006

Bitterness and astringency of the monomeric flavan‐3‐o!s ( + )‐catechin and (−)‐epicatechin were rated using time‐intensity (T‐I) methodology. Three concentration levels (0.5. 0.9 and 1.2 g liter−1) oi each compound were assessed, and the parameters time to maximum intensity (TMAX), intensity at the maximum (IMAX) and total duration (TTOT) were extracted from the T‐I curves. No differences in TMAX for either bitterness or astringency were found between these chiral isomers or as a function of concentration within a compound. Epicatechin had a significantly higher bitter IMAX than catechin at all three concentration levels, and had a significantly longer TTOT at the two higher concentrations. Epicatechin was more astringent than catechin. but this was only significant at one concentration. Astringency TTOT was longer for epicatechin, although this was nonsignificant at the lowest concentration. The three concentrations of catechin were significantly different for both bitterness and astringency IMAX and TTOT. Epicatechin showed evidence for the astringency response plateauing above the 0.9 g litre−1 level. n‐Propylthiouracil status had no effect on perception of either bitterness or astringency.
Microbial decontamination of black pepper by ozone and the effect of the treatment on volatile oil constituents of the spice
Authors: Zhao Jian , Cranston Peter M
Published: November 2006

The use of ozone as a substitute for ethylene oxide to decontaminate whole black peppercorn and ground black pepper and the effects of ozone on the volatile oil constituents of the spice were studied. Black peppercorns were immersed in water and sparged with ozonised air (ozone concentration, 6·7 mg litre−1) for 10 min at an air flow rate of 6 litre min−1. This treatment reduced the microbial population of peppercorn by 3–4 log numbers. Ground black pepper with various moisture levels was sparged with ozonised air for up to 6 h. This treatment reduced the microbial population by 3–6 log numbers, depending on the moisture content of the spice. Higher moisture content led to a greater reduction in microbial load. The volatile oil constituents of the spice with and without ozone treatment were extracted with isopropyl ether and analysed by gas chromatography and gas chromatography‐mass spectrometry. Ozone treatment of ground black pepper resulted in the oxidation of certain volatile oil constituents while the treatment had no significant effect on the volatile oil constituents of whole peppercorn.
Breakdown of peptides from a soya protein hydrolysate by rumen bacteria. Simultaneous study of enzyme activities and of two physico‐chemical parameters: Molecular weight and hydrophobicity
Authors: Depardon Nathalie , Debroas Didier , Blanchart Gerard
Published: November 2006

Breakdown of soya peptides by an inoculum of ruminal mixed bacteria was studied in vitro. Peptides were hydrolysed at 75% after 5 h. The dipeptidyl‐aminopeptidase type 1 (DAP‐1), exoaminopeptidase and leucine aminopeptidase (LAP) activities were measured using GlyArg‐MNA, Ala‐pNA and Leu‐pNA as substrates, respectively. While the total proteolytic activity remained stable throughout peptide breakdown, the DAP‐1 already present at the beginning of fermentation was multiplied by two. This peptidase activity is a major index for the presence of Prevotella ruminicola. The exoaminopeptidase activity increased during the exponential phase of bacterial growth. A peak of LAP activity was observed after 3 h of incubation. This activity which was associated to the production of lactate after 3 h suggested the Streptococcus bovis was present in the environment. Measuring by high‐performance liquid chromatography (HPLC) gel filtration the size of peptides during their breakdown showed that high‐molecular‐weight peptides (4000–5000) were apparently more rapidly broken down relative to intermediate peptides (2000–3000) and to small assimilable peptides (1000–500). Separation of soya peptides by reverse‐phase HPLC showed a disappearance of hydrophilic and hydrophobic peptides. This study showed that there is no preferential breakdown of hydrophilic peptides relative to hydrophobic peptides in vitro.
Metabolic changes of biochemical constituents in developing fennel seeds (Foeniculum vulgare)
Authors: Gupta Kaushalya , Thakral K K , Gupta V. K. , Arora S K
Published: November 2006

Fennel (Foeniculum vulgare) is the major spice/condimental crop of Haryana, generally used in India for preparing pickles and in vegetable cooking. Flowers were tagged at anthesis, fennel seeds (local variety) were collected at 1‐week intervals after 40 days from anthesis for studying biochemical constituents. Moisture and protein contents decreased significantly with the advancement of seed development. Oil content ranged from 68 to 135·7 g kg−1 (dry weight basis), which increased with seed development. The oil content was greater in mature seeds. The presence of phytate (11·35–13·10 mg g−1) was also observed, which affects the availability of Zn and Fe. Fennel seeds were found to be a rich source of micro‐ and macroelements. Neutral detergent fibre, acid detergent fibre, cellulose and lignin contents increased significantly with the advancement of seed development. Oleic and linoleic fatty acids were found to be major fatty acids and variable proportions of different fatty acids were observed.
Biodegradation of cell wall components of maize stover colonized by white‐rot fungi and resulting impact on in‐vitro digestibility
Authors: Chen Jinchuan , Fales Steven L , Varga Gabriella A , Royse Daniel J
Published: November 2006

Treatment of crop residues with some species of white‐rot fungi can enhance digestibility. This study was conducted to investigate changes in in‐vitro dry matter disappearance (IVDMD) and degradation of cell wall constituents in maize (Zea maize L) stover treated with three white‐rot fungi: Cyathus stercoreus, Phlebia brevispora and Phanerochaete chrysosporium. Solid fermentation of maize stover for 28 days at 27°C improved IVDMD from 409 g kg−1 (control) to 514 g kg−1 for P brevispora and 523 g kg−1 for C stercoreus. In contrast, growth of P chrysosporium reduced IVDMD from 409 to 298 g kg−1. All fungi degraded cell wall p‐coumaric acid (PCA) and ferulic acid (FA), but P chrysosporium was the least effective in degrading PCA and FA. Conversely, P chrysosporium degraded lignin 1·6 times more effectively than C stercoreus and 1·4 times more than P brevispora, indicating that lignin degradation alone cannot account for the IVDMD enhancement and that degradation of PCA and FA may be important. Hemicelluloses were preferentially and highly utilized by all the fungi. Cellulose was extensively degraded only by P chrysosporium (69% lost after 28 days of incubation), while substrate colonized by the other two fungi retained more than 84% original cellulose. Incubation of C stercoreus and P brevispora decreased the concentrations of both xylose and arabinose, but increased glucose concentration, whereas P chrysosporium removed less xylose and decreased glucose concentration. Preferential removal of arabinose over xylose by the fungi caused an increase in the xylose to arabinose ratio of the treated residues. Enhanced digestibility may have resulted from cleavage of lignin‐carbohydrate bonds. Results of this study suggest that digestibility enhancement of maize stover colonized by white‐rot fungi is regulated by a complex combination of various factors, including the degradation of structural carbohydrates, cell wall phenolic acids and lignin.
Effect of the phenol antioxidant type on the kinetics and mechanism of inhibited lipid oxidation in the presence of fatty alcohols
Authors: Kortenska Vessela D , Yanishlieva Nedjalka V
Published: November 2006

A kinetic analysis of inhibited lipid autoxidation in the presence of a phenol antioxidant and a hydroxy compound is proposed. It is based on studies of the dependence of the WROH/Winh ratio (between the inhibited oxidation rates in presence and absence of a hydroxy compound) on the hydroxy compound concentration. This analysis permits establishing the mechanism of action of the hydroxy compound in the presence of different types of phenol antioxidants during inhibited lipid oxidation. The kinetic analysis has been applied to the oxidation at 80°C of triacylglycerols of sunflower oil (TGSO) inhibited by 0.1 mM hydroquinone, butylated hydroxytoluene (BHT) or α‐tocopherol in the presence of different concentrations of 1‐tetradecanol (1‐TD) and 1‐octadecanol (1‐OD). A linear character of this dependence is established during hydroquinone‐inhibited oxidation of triacylglycerols of sunflower oil in presence of 1‐TD. In the case of α‐tocopherol this dependence is linear for both 1‐TD and 1‐OD. The equilibrium constant of interaction between the phenol antioxidant and the fatty alcohols is determined by the angle coefficient of the linear dependence. The hydroquinone‐inhibited autoxidation of TGSO in the presence of 1‐OD has shown a non‐linear character of the dependence under consideration. A kinetic model describing simultaneous participation of 1‐OD in reaction with both the phenol antioxidant and the lipid hydroperoxides is deduced. Studying the kinetics of BHT‐inhibited autoxidation of TGSO in the presence of 1‐OD, it has been shown that due to steric reasons there is no interaction between 1‐OD and BHT, 1‐OD participating in the process only by accelerating the decomposition of the lipid hydroperoxides.
Studies on the effect of protectants on Lactobacillus acidophilus strain dehydrated under controlled low‐temperature vacuum dehydration and freeze‐drying by using response surface methodology
Authors: King V An‐Erl , Lin Haur‐Jie
Published: November 2006

Ca2+ (0–60 g litre−1), glycerol (0–100 g litre−1), and non‐fat dry milk solids (NFDMS, 0–140 g litre−1) were combined to study their effects on the survival of Lactobacillus acidophilus in controlled low‐temperature vacuum dehydration and freeze‐drying. A three‐variable (each at three‐levels) design method was used and analysed by fitting a quadratic response surface. These factors were found to be significantly effective on survival. Fitted quadratic regression equations were plotted using a graphing software package. Conditions for the best survival of freeze‐drying was found to be Ca2+ 5.34 g litre−1. NFDMS 100.8 g litre−1, and glycerol 41.5 g litre−1 and that of controlled low‐temperature vacuum dehydration was Ca2+ 5.67 g litre−1, NFDMS 107.1 g litre−1, and glycerol 41.0 g litre−1. Models obtained were tested using t‐tests. Survival of freezing under different conditions was found to be not significantly different.
The effects of acidification and temperature during washing of Spanish‐style green olives on the fermentation process
Authors: Sánchez A , García P , Rejano L , Brenes M , Garrido A
Published: November 2006

The effects of temperature (22 and 40°C) and acidification by HCI, H3PO4 and fermentation brine during the washing step of Spanish‐type green olive processing were studied. When acids were added to the washing waters, the diffusion rates of sugars and polyphenols from the flesh of olives to the surrounding liquid diminished. This phenomenon could be related to the pH of the washing water. Both heating and acidification during the washing step influenced later lactic acid fermentation and the final values of the combined acidity in brines. Thus, when the washing step was carried out at 40°C the fermentation process was accelerated.
Effect of epinephrine administration on glycogen metabolism in red and white muscle of anaesthetized pigs (Sus scrofa domesticus)
Authors: Fernandez X , Levasseur P , Ecolan P , Wittmann W
Published: November 2006

The glycogenolytic effect of exogenous epinephrine was studied in white (Longissimus) and red (Trapezius) muscle of anaesthetized pig. In addition, we assessed the metabolic action of epinephrine during the 3 h following the cessation of perfusion. Twelve purebred Large White pigs, averaging 80 kg live‐weight, were used. The animals were anaesthetized and perfused (0–15 min) with 5 μg kg−1 min−1 epinephrine or saline (control animals). Blood samples were taken to determine plasma levels of glucose, lactate and non‐esterified fatty acids (NEFA). Muscle samples were taken to determine the concentrations of glycogen and related metabolites, and the activity ratio of the enzyme glycogen phosphorylase. Control animals showed stable levels of plasma and muscle metabolites during the 3 h anaesthesia. However, the resting level of the activity ratio of phosphorylase was high (80%). Epinephrine treatment induced significant increases in plasma metabolites and an overall significant glycogen depletion. The extent of epinephrine‐induced glycogenolysis was greater in the red Trapezius than in the white Longissimus muscle. This was associated with a greater rise in the muscle lactate content and in the activity ratio of phosphorylase in the Trapezius muscle during epinephrine administration. In both muscles, no significant glycogen depletion was observed during 3 h following the cessation of epinephrine administration. This occurred despite the fact that the activity ratio of phosphorylase remained high in the Longissimus muscle until the end of the experiment.
Nε‐carboxymethyllysine is formed during heating of lysine with ketoses
Authors: Ruttkat Axel , Erbersdobler Helmut F
Published: November 2006

In a model system with lysine monohydrochloride and various reducing sugars, the contents of Nε‐carboxymethyllysine (CML) were measured after heat treatment at 98°C for 3–24 h. The results show for the first time that CML could be formed by the reaction of lysine and fructose or lysine and sorbose. The formation of CML also shows time‐dependent differences between aldoses and ketoses. After heating up to 6–12 h, the reaction of lysine with ketoses leads to similar amounts of CML as the reaction with aldoses, whereas after longer heating significantly more CML was produced by the reaction with aldoses. The highest CML contents (2380 mg CML kg−1 lysine) were measured in the galactose model system after heating for 24 h.
The effects of intravenous supplements of amino acids on the milk production of dairy cows consuming grass silage and a supplement containing feather meal
Authors: Choung Jai‐Jun , Chamberlain David G
Published: November 2006

Two experiments were carried out to identify the limiting amino acids for milk production in dairy cows consuming diets based on grass silage and a cereal‐based supplement containing feather meal as the only high‐protein ingredient. In the first experiment, the yield of protein in milk was increased by 26% in response to intravenous infusion of a mixture of histidine, lysine, methionine and tryptophan. In the second experiment, omission of methionine from the infused mixture led to no reduction in the milk response compared with that seen with the mixture of four amino acids, confirming that methionine was not limiting milk production from the basal diet. The results have important implications for the choice of complementary proteins to blend with feather meal in diets for ruminants.
Effects of raw materials, processing conditions and packaging on the quality of plantain chips
Authors: Onyejegbu Christine A , Olorunda Ayodele O
Published: November 2006

The effects of raw material, processing conditions and packaging on the quality of plantain chips were investigated. Two cultivars of plantain Musa spp—Agbagba and Obino lewai—as well as cooking banana were used for the study. The fruits were at stages 1 to 4 of the banana ripening chart. The study started with a consumer survey aimed at product definition. This was followed by series of experiments to determine the effects of raw material, processing conditions and packaging on the quality of plantain chips. A correlation analysis was also carried out on the physical and chemical characteristics of raw plantain. The work revealed that the stage of ripeness of raw material had some effect on the quality of chips as there was gradual increase in pulp/peel ratio and sugar was significantly different (P < 0·05). Moisture content of pulp/texture of pulp, texture of pulp/sugar content of pulp and texture of pulp/ripening stages were negatively correlated, while pulp/peel ratio and moisture content of pulp were positively correlated. Chips packed in 80 μm high‐density polyethylene pouches and stored at various relative humidities had extended shelf‐life compared with the low‐density polyethylene packed chips stored at the same relative humidities. This was due to the inadequacy of the low‐density polyethylene in giving the required protection against moisture transmission thereby resulting in soggy chips in shorter periods. The implication of the findings on the formulation of a guideline for the processing of a good‐quality plantain chips for the marketing system is discussed.
Biochemical changes in cucumber mosaic virus (CMV)‐infected Amaranthus and Chenopodium
Authors: Prakash Dhan , Raj S K , Singh B P
Published: November 2006

The changes in biochemical contents of vitamin C, total carotenoids, chlorophyll, protein and amino acid profile in the CMV‐infected leaves/seeds of Amaranthus and Chenopodium species were studied. The amount of protein was higher (9–20%), while vitamin C (37–79%), carotenoids (19–52%) and chlorophyll (5–45%) were lower in all the tested species. Amino acid composition of the infected leaves/seeds also showed some significant changes compared with healthy specimen.
Diffusion of citric and ascorbic acids in pre‐peeled potatoes and their influence on microbial growth during refrigerated storage
Authors: Giannuzzi Leda , Lombardi Alejandra M , Ezaritzky Noemi
Published: November 2006

The most common chemical preservatives used to inhibit both enzymatic browning and microbial growth in pre‐peeled potatoes are sodium sulphite and bisulphite. Since 1987 the FDA has limited their use as food ingredients; consequently, during recent years the tendency to replace sulphites by GRAS chemical additives such as citric and ascorbic acids has become stronger. In the present work, surface colour variations, exudate production and microbial growth were analysed on pre‐peeled potatoes treated with citric and ascorbic acids. These preservatives were applied individually and as mixtures; shelf‐life was extended and microbiologically safe products were obtained. Mathematical models were solved to analyse the diffusion of these acids during immersion and storage periods in order to determine the concentration profiles within the product and to predict the surface concentration to which the microorganisms are exposed.
Sensory evaluation of Atlantic salmon fed three types of herring‐based diet
Authors: Parrish Christopher C , McLeod Cathy A , Ackman Robert G
Published: November 2006

Atlantic salmon (Salmo salar) were fed three different types of commercial and experimental herring‐based feeds and, at the end of the feeding trials, sensory panels evaluated the acceptability of the salmon fillets. The feeds were all made from Atlantic herring but using different procedures: silage feeds were made from fermented herring, moist salmon feeds from fresh herring, and dry feeds from herring meal. Silage feeds were compared with either one or two of the other feeds in three feeding trials. Growth rates of animals fed a commercial silage feed and two dry feeds were similar, although growth on the commercial silage feed tended to be better. However, growth on commercial or experimental silage feeds was significantly lower (P < 0·001) than on either commercial or experimental moist feeds. Analysis of covariance indicated that there were no significant tank effects. At the end of the feeding trials, sensory evaluation of fish fillets by triangle test indicated no significant difference (P > 0·05) in fillet flavours or appearance between fish fed silage and fish fed the other diets.
Texture of Chinese water chestnut: Involvement of cell wall phenolics
Authors: Parker Mary L , Waldron Keith W
Published: November 2006

Chinese water chestnuts (CWC) fail to soften during cooking. This is due to thermal stability of cell wall polymers involved in cell‐cell adhesion. Information concerning these polymers was obtained by subjecting CWC tissues to a range of chemical and biochemical treatments designed to cleave selectively cell wall chemical bonds. Neither chelating agents nor weak base (Na2CO3, 0·05 M) facilitated vortex‐induced cell separation (VICS) in fresh or canned tissues. However, VICS could be induced after extraction in dilute, cold alkali (0·1 M KOH), dilute hot acid, or a purified, specific endoxylanase. The CWC cell walls also exhibited considerable pH‐dependent autofluorescence which originated mainly from ferulic acid and its derivatives. This disappeared during alkali‐induced VICS. The results are consistent with the involvement of ferulic acid‐containing cell wall hemicelluloses in the thermal stability of cell‐cell adhesion and therefore texture in CWC tissues.
Marketable and nutritional quality of leeks as affected by water and nitrogen supply and plant age at Harvest
Authors: Sørensen Jørn N , Johansen Anders S , Kaack Karl
Published: November 2006

The marketable and nutritional quality of leeks as affected by nitrogen fertilisation, water supply, and plant age at harvest was investigated during 1991 and 1992. The yield of marketable leeks increased with increasing nitrogen supply, although only small differences were observed between 160 and 280 kg total N ha−1. The total nitrogen supply includes soil mineral nitrogen within the 0–50 cm depth. The yield was lower when leeks were grown with less frequent irrigation, ie irrigation at a soil water potential of −0.09 MPa at 20 cm depth. On average, the yield of leeks increased until harvest in the middle of October, 200 days after sowing. The concentration of nitrate increased and the concentrations of dry matter and potassium decreased with increased nitrogen supply. Leeks grown with less frequent irrigation showed increased concentrations of dietary fibre, vitamin C, nitrate, protein, calcium, magnesium, and manganese. The nutritional quality of leeks improved with increased plant age at harvest because the concentration of potassium increased and the concentration of nitrate decreased.
The contribution of fertiliser nitrogen to leachable nitrogen in the UK: A review
Authors: Davies D B , Sylvester‐Bradley R
Published: November 2006

Evidence relating to nitrate leaching was taken from series of extensive field experiments conducted to support guidance on fertiliser use. Over the last 50 years, it is estimated that increased fertiliser N use on intensive wheat in the UK, has resulted in an increase of 36 kg N ha−1 year−1 leachable nitrate. Probably more than one‐third of this change is due to larger yields resulting in a gradual build up in soil organic matter, the remainder to annual effects of fertiliser application. This justifies the association generally made between fertiliser used and nitrate leached and supports the value of some control of fertiliser use in order to restrict nitrate concentrations in drinking water.
The extraction of radiolabelled inorganic sulphate from blood plasma
Authors: Wang Y , Barry T N
Published: November 2006

A study was conducted into factors governing the efficiency of the ion exchange method for extracting 35S‐labelled inorganic sulphate (SO) from blood plasma, using Dowex′1‐X8 ion exchange resin. The study compared effects of trichloroacetic acid (TCA) strength as protein precipitant, different HCl strengths as resin eluent, sodium citrate/HCl (SC/HCl) versus HCl as eluents, and evaluated ultrafiltrated (UF) plasma upon the adsorption and recovery of added 35SO. Both adsorption and release of 35SO from the resin were inhibited by the presence of TCA, and HCl was not as effective as 1 M SC/2 M HCl in releasing 35SO adsorbed to resin. The rates of 35SO adsorbed onto resin and recovered were markedly increased by using UF plasma and 1 M SC/2 M HCl as eluent, with the values being 96.3 ± 0.11% and 91.1 ± 0.39%, respectively, where 1 g resin was used. Therefore, the use of UF for deproteinising and 1 M SC/2M HCl as eluent are recommended for extracting 35SO from blood plasma when Dowex′1‐X8 resin is used as the ion exchanger.
Anisotropic swelling of cell walls of sugar beet tissue: Influence of ion‐exchange and sucrose
Authors: Gieringer Rita , Steinert Peter , Buttersack Christoph , Buchholz Klaus
Published: November 2006

Cell walls of sugar beet tissue (Beta vulgaris var altissima Döll), the cell and vacuolar membrane of which were destroyed by heat or the action of lipophilic substances, were observed by transmission electron microscopy. The average thickness of secondary walls (SW) and the region composed of the middle lamella and two primary walls (PW) was statistically evaluated and compared with the swelling of the entire denaturated tissue. By introducing different counter‐ions with water as solvent, the extension along the wall E2 increased in the order H+ < K+ ∼ Ca2+ < La3+, and the extension across the wall (SW plus PW) E2 increased in the order Ca2+ ∼ K+ < La3+ < H+. Replacement of the swelling medium by sucrose solution (0.5 M) caused either an increase of the wall thickness (K+, Ca2+, La3+) or a contraction (H‐form); the anisotropy E2E3 was either negative (H+, Ca2+, La3+) or positive (K+). Comparison of the PW with the SW region mostly yielded a ratio of Ezpw/Ezxm between 1 and 2. The ion‐exchange K+→Ca2+ was predominantly manifested in a change of the PW region, while the influence of sucrose on the K+‐treated wall seemed to be confined to the SW region. Specimens in the H‐form in water showed a further increase of the wall thickness (SW and PW) when the pH was reduced from 7 to 3. (At pH 3 the carboxyl groups inside the wall must exist nearly completely in the non‐dissociated state.) All the changes of swelling observed may be explained by a superposition of electrostatic and anisotropic hydrophobic interactions between the matrix polysaccharides.
Effects of oil roasting temperature and time on the quality of two Macadamia integrifolia cultivars
Authors: Mason Richard L , Bowden Ray P , Nottingham Stephen M
Published: November 2006

The effects of oil roasting temperature and time on the quality of kernels from two Macadamia integrifolia cultivars, were determined. A high quality product was obtained by roasting at 115°C for 19–35 min, 125°C for 10–14 min or 135°C for 4 min. There was a significant deterioration in the quality of nuts from all roasting treatments when stored for 6 months at ambient temperature in lacquered cans at a pressure of −85 kPa. Further deterioration had occurred after 12 months storage.
Reduction of proteolysis during ensilage of perennial ryegrass by protease inhibitors
Authors: Wetherall Jane A , Armstrong David G , Finlayson Heather J , Rooke John A
Published: November 2006

Two experiments were carried out to assess the effectiveness of protease inhibitors in reducing proteolysis during ensilage. Perennial ryegrass (Lolium perenne) (279 g dry matter (DM) kg−1, experiment 1 and 170 gDM kg−1 experiment 2) was ensiled in laboratory silos for 82 and 50 days, respectively. With the exception of the application of formic acid (1.5 g kg−1) plus formalin (3 g kg−1) in experiment 1, all silages had pH values of less than 4.0 and lactic acid concentrations of greater than 100 g kg−1 DM. Application of the cysteine endopeptidase inhibitor E‐64 (1‐trans‐epoxysuccinyl‐leucylamido(4‐guanidino) butane, 22.5 mg kg−1 reduced proteolysis during ensilage as measured by a reduction in the quantities of soluble non‐protein N in silage to 0.76 and 0.91 of control values (528 and 643 g kg−1 total N) in experiments 1 and 2, respectively. In experiment 2 increasing the application rate of E‐64 from 22.5 to 45 mg kg−1 further reduced the extent of proteolysis from 0.91 to 0.75 of control soluble non‐protein N concentrations. Proteolysis was also reduced in experiment 2 by two other cysteine endopeptidase inhibitors, antipain (32 mg kg−1, 0.81 of control) and cystain (1.2 mg kg−1; 0.89 of control). Pepstatin A (300 mg kg−1), an inhibitor of aspartic acid endopeptidases, did not reduce soluble non‐protein N concentrations in experiment 1 but did do so in experiment 2 (0.81 of control). Treatment of grass at ensiling with Lactobacillus plantarum (106 g−1) reduced silage non‐protein N concentrations to 0.83 of the control. The effects of E‐64 and pepstatin A and of E‐64 and L plantarum in experiment 2 were addive. Cysteine endopeptidases therefore play an important role in protein breakdown during ensilage.
Changes in the sulphur status of British wheat grain in the last decade, and its geographical distribution
Authors: Zhao Fang‐Jie , McGrath Steve P , Crosland Adrian R , Salmon Susan E
Published: November 2006

In 1992 and 1993, respectively, 400 and 393 wheat grain samples were collected representatively from the major wheat‐growing areas in Britain. Concentrations of S in the grain and the N: S ratios were determined, and the variations due to variety and geographical distribution were analysed. Grain S concentration ranged from 0.54 to 2.09, with a mean of 1.43 mg g−1 in 1992, and from 0.80 to 1.67, with a mean of 1.26 mg g−1: in 1993. The ranges of grain N: S ratio were 13.3‐29.6, with a mean of 15.8 in 1992, and 11.5‐25.9, mean 15.6 in 1993. Breadmaking varieties contained significantly greater N and S concentrations in the grain than other varieties, but only small differences were found in the N: S ratio in grain. In 1992 and 1993, 7 and 26% of the samples had a S concentration below the critical value of 1.2 mg g−1, respectively, whereas 10 and 7% of the samples had an N: S ratio greater than the critical value of 17. In both years 2.5% of the samples satisfied both criteria of S deficiency. Comparison of the results of 1992–1993 with those of 1981–1982 (Byers et al. J Sci Food Agric 38 (1987) 151–160) showed a significant decrease in the S status of British wheat grain during the 10–12 year period. The decrease can be attributed mainly to decreased S inputs, particularly from atmospheric deposition. The pattern of geographical distribution of grain S concentrations was not as strong as it was in the 1982 survey. However, it was still apparent that grain samples with small S concentrations were located mainly in Scotland, northern England, and the west and southwest of England, whereas the largest S concentrations occurred mainly in the areas near to or down‐wind of the industrial conurbations of central England.
The effects of cryoprotectants on the sensory properties of frozen blue crab (Callinectes sapidus) meat
Authors: Henry L K , Boyd L C , Green D P
Published: November 2006

The sensory properties of cryogenically frozen crab meat, treated with polydextrose, a blend of sucrose/sorbitol/phosphate or water was compared with pasteurised crab meat using both trained and consumer panels. Samples were vacuum sealed, cryogenically frozen and stored at −29°C for 32 weeks. A trained panel evaluated changes in appearance, aroma, flavour, and texture at periods of 0, 4, 8, 16, 20, 24, 28 and 32 weeks while a consumer panel evaluated sensory changes after 0, 16 and 32 weeks of storage. An untreated cryogenically frozen reference sample was stored at −65°C. Polydextrose and sucrose/sorbitol/phosphate treatments were closest in sensory attributes to fresh crab meat in that they had fewer adverse changes in quality than the water, reference or pasteurised treatments. Panellists detected more sour, rancid, and ammonia notes and less fresh crab flavor in the pasteurised sample. All of the cryogenically frozen samples were closer to fresh crab meat, in quality attribute terms than pasteurised crab mat. Consumer panel evaluations were in agreement with trained panel assessments showing that cryoprotectants were effective in delaying the deterioration of sensory attributes during frozen storage.
Diglyceride content and composition as indicators of palm oil quality
Authors: Siew Wai Lin , Ng Wee‐Lam
Published: November 2006

The diglycerides present in palm oil and palm oil fractions were analysed using thin‐layer and gas chromatography. The diglyceride contents and compositions of commercial palm oils were compared with those of oils extracted from fresh fruits. The results showed that the diglycerides present in palm oil and its fractions consist mainly of palmitoyloleoyl‐, dioleoyl‐ and dipalmitoyl‐sn‐glycerol. The levels of diglycerides in fresh palm oils (17‐38 g kg−1) were lower than those in commercial palm oils (40‐75 g kg−1). In the oils from fresh fruits the 1,2‐diglyceride predominates over the 1,3‐isomer whereas in commercial oils the reverse is observed. The ratio of 1,3‐ to 1,2‐diglycerides in fresh oils depends on the degree of maturity of the fruit. Furthermore, the 1,3‐diglycerides increase rapidly after the 20th week of anthesis, while the 1,2‐diglycerides decrease rapidly over the same period of time. Storage of ripe fruits and oils over 10 days also resulted in further increase of the 1,3 : 1,2‐diglyceride ratio. Thermal treatment of oils caused the most significant changes in the ratio. Isomerisation in the fruit and in the oil during thermal treatment is discussed. Based on this study, it is proposed that the diglyceride contents and their ratios be used as indicators of oil quality in addition to other widely used quality parameters such as peroxide and anisidine values.
Optimization of process conditions and quality of salted dried tilapia (Oreochromis niloticus) using response surface methodology
Authors: Nketsia‐Tabiri J , Sefa‐Dedeh S
Published: November 2006

Tilapia (Oreochromis niloticus) was processed by varying salting time (0‐24 h), drying time (6‐20 h) and drying temperature (40‐60°C) using the central composite rotatable design. Equations for predicting objective and subjective indices were developed. The critical salting times for attaining minimum moisture were 20.5, 12 and 8.5 h, respectively, for products dried at 40, 50 and 60°C. At each salting time the mean hardness score was dependent on the drying temperature and time whilst the mean colour and acceptability scores were influenced by the drying temperature. Salting and drying conditions could be manipulated to produce salted‐dried tilapia of acceptable quality.
Effect of liming on the chemical composition of soils
Authors: Riggs Katherine S , Rimmer David L , Syers J Keith
Published: November 2006

The effects of adding two calcitic and two dolomitic limestones at three rates (0, 1 and 2 times the lime requirement, determined by Ca(OH)2 titration) to six acid UK topsoils were investigated in an incubation experiment over 70 days. After only 7 days, large increases in soil pH and exchangeable Ca values were obtained. However, these soil properties changed at different rates. The relatively constant pH values after 14 days suggested that the liming reaction was complete at that stage. In contrast, exchangeable Ca increased throughout the incubation period but after 70 days only approximately 50 and 30% of the Ca added had become part of the exchangeable fraction in the two lime treatments. Consequently, measurement of soil pH is not as suitable as that of exchangeable Ca for following the dissolution of limestones in soils. Additions of calcitic limestones decreased soil exchangeable Mg in the agriculturally important pH range of 5.0‐7.5. The magnitude of the decrease was proportional to the initial soil exchangeable Al content (r= −0.68;P< 0.05) and the amount of calcitic limestone added (r= −0.78;P< 0.001). Additions of dolomitic limestone increased the amounts of exchangeable Ca and Mg, making it a particularly suitable liming material for soils where the potential for lime‐induced Mg deficiencies exists.
GC‐MS identification of volatile components of Galician (Northwestern Spain) white wines. Application to differentiate Rías Baixas wines from wines produced in nearby geographical regions
Authors: García‐Jares C M , García‐Martin M S , Carro‐Mariño N , Cela‐Torrijos R
Published: November 2006

A capillary gas chromatoaraphy‐ion trap mass spectrometry linked technique improved with a programmable temperature injector was applied to identify some volatile components (more than 100 compounds) in certified brand of origin (CBO) Rias Baixas white wines. Some of them have not been previously reported in young white wines. Forty of these components were determined by capillary gas chromatogtaphy with flame ionisation detection in Rias Baixas wines and in other Galician white wines. By means of muitivariate techniques of data exploration as hierarchical cluster analysis and principal components analysis two main groups of samples (Rias Baixas and non‐Rias Baixas wines) were observed. However, some outliers were also pointed out among the two groups of wines. One sample elaborated with Albariño grapes out of the delimited Rias Baixas area showed the most anomalous behaviour. Two samples CBO Rias Baixas seemed to be produced by mixture of grape varieties not allowed by the CBO regulations. Exploratory analysis results were confirmed using supervised techniques of data classification as K‐nearest neighbours and soft independent modelling of class analogies.
Effect of ethylene on storage life of lettuce
Authors: Kim Gun‐Hee , Wills Ron B H
Published: November 2006

Lettuce was held in air containing ethylene at 0.005‐1.0 μl litre‐1 at 20°C and 0°C to examine the effect of ethylene levels on quality during storage. Reducing the ethylene level was found to extend storage life by delaying leaf browning at both temperatures. The level of ethylene around commercially marketed lettuce was found to range from 0.11 to 0.85 μl litre‐1. Storage of lettuce in polyethylene bags to minimise water loss and the inclusion of potassium permanganate to reduce the level of ethylene gave a significant increase in market life at 20°C and 0°C.