Showing papers in "Journal of the Science of Food and Agriculture in 1984"
TL;DR: A new approach to profile analysis is described in which each assessor produces individual profiles of the products, using his or her own terms for describing them without the need to explain the meaning of such terms.
Abstract: The paper describes a new approach to profile analysis in which each assessor produces individual profiles of the products, using his or her own terms for describing them without the need to explain the meaning of such terms. The spatial configurations derived from individual profiles are rationalised by generalised Procrustes statistics. The result is a consensus configuration revealing the interrelationships between the samples for the panel as a whole. An experiment conducted on commercial ports using ten assessors, both expert and non-expert, illustrates the technique.
330 citations
TL;DR: In this article, a detailed description is given of the construction and operation of a system of small wind-tunnels used in the measurement of ammonia volatilisation from grass swards.
Abstract: A detailed description is given of the construction and operation of a system of small wind-tunnels used in the measurement of ammonia volatilisation from grass swards. In the design of the system, emphasis was placed on the requirements that (i) natural sward conditions should be influenced as little as possible, and (ii) airspeed through the tunnels should be controllable in the range normally encountered in the field. An analyser is described which incorporates an ammonia-sensing probe; it was used to monitor automatically and continuously the concentration of ammonia in air entering and leaving the tunnels. The tunnels were found to have only small effects on sward conditions. Differences between simultaneous measurements of temperature made inside and outside the tunnels were rarely more than 1°C for air temperature and 2°C for soil temperature at 3 cm depth. The potential of the system was examined in a study comparing the loss of ammonia through volatilisation from swards treated with natural urine or an artificial urine. There were marked differences in the rates of volatilisation from the two urines although the total loss of nitrogen was similar from both, amounting to about 3% of the nitrogen applied.
205 citations
TL;DR: Investigations of the effects of ortho-, pyro-, and tripolyphosphate on the thermal denaturation of myosin showed that added pyrophosphate destabilised theMyosin molecule by about 9 K compared to the effectsof ortho andtripolyph phosphate, even though the latter was probably hydrolysed to ortho- and diphosphate.
Abstract: The thermal denaturation of rabbit skeletal muscle myosin and its subfragments was investigated by differential scanning calorimetry. The thermal denaturation of myosin was shown to occur via three (at least) partly independent cooperative endothermic processes. The temperatures at which these processes occurred (312, 317 and 323 K at pH 6.0 and I=1.0) were shown to vary with pH (5.5–8.0) and I (0.05–1.0). The apparent enthalpy of denaturation of myosin was also shown to be dependent on pH and I. By comparing thermograms of myosin with those of the isolated myosin subfragments, the three major processes associated with the thermal denaturation of rabbit myosin could be tentatively assigned to different regions of the myosin molecule, namely, the helical tail, the ‘hinge-region’ and the globular heads. The ‘hinge-region’ thermal denaturation was shown to be reversible at pH 6.0 and I=1.0. Investigations of the effects of ortho-, pyro-, and tripolyphosphate on the thermal denaturation of myosin showed that added pyrophosphate destabilised the myosin molecule by about 9 K compared to the effects of ortho and tripolyphosphate, even though the latter was probably hydrolysed to ortho and diphosphate.
188 citations
TL;DR: A simple isocratic h.p.c. technique was developed for the simultaneous quantitative analysis of lactic, formic, acetic, propionic, isobutyric, n-butyric and isovaleric acids in aqueous acid extracts of silage as discussed by the authors.
Abstract: A simple isocratic h.p.l.c. technique was developed for the simultaneous quantitative analysis of lactic, formic, acetic, propionic, isobutyric, n-butyric and isovaleric acids in aqueous acid extracts of silage. An Aminex HPX-87H strong cation exchange resin column at 41°C, 0.0025M H2SO4 mobile phase and ultraviolet detector at 210 nm were utilised. Estimated recoveries of acids added to silage ranged from 98.2 to 103.5%.
161 citations
TL;DR: In this paper, the influence of components contributing to the colour and brightness of flour, flour paste and Chinese and Japanese style noodles has been investigated, and differences in brightness and yellowness were attributed to wheat cultivar, milling extraction rate, protein content, starch damage and brown and yellow pigments.
Abstract: The influence of components contributing to the colour and brightness of flour, flour paste and Chinese and Japanese style noodles has been investigated. Differences in brightness and yellowness were attributable to wheat cultivar, milling extraction rate, protein content, starch damage and brown and yellow pigments.
157 citations
TL;DR: Gel-forming, cross-linked polyacrylamides are new formulations of soil conditioners for use where short-term or persistent drought inhibits plant growth as mentioned in this paper, and polymers with high absorption capabilities and low binding tensions in the range pF 2 to 4.2 could be important aids to growth of agricultural, horticultural and forestry crops in drought-prone environments.
Abstract: Gel-forming, cross-linked polyacrylamides are new formulations of soil conditioners for use where short-term or persistent drought inhibits plant growth. Most commercial products absorb water to many times their own weight thus improving the water storage properties of porous soils, and delaying the onset of the permanent wilting percentage where evaporation is intense. However, there is notable variation between products in the binding tension of absorbed moisture, so changes in field capacity are of little diagnostic value for the soil moisture available to plants. Nevertheless, polymers with high absorption capabilities and low binding tensions in the range pF 2 to 4.2 could be important aids to growth of agricultural, horticultural and forestry crops in drought-prone environments.
156 citations
TL;DR: In this paper, the use of near infrared (n.i.r.) diffuse reflectance spectroscopy in the monitoring of automatic metering equipment used for fat, sucrose, dry flour and water in short dough biscuit production has been investigated.
Abstract: The possible use of near infrared (n.i.r.) diffuse reflectance spectroscopy in the monitoring of automatic metering equipment used for fat, sucrose, dry flour and water in short dough biscuit production has been investigated. The experimental design involved randomisation of a standard pilot scale Lincoln biscuit recipe to produce calibration and prediction samples and comparison of n.i.r. results with the levels of ingredients determined from the recipe. The use of several strategies based on regression analysis for selection of the ‘best’ wavelengths for reflectance measurements for each analyte was investigated. A novel strategy based on computing the regressions on analyte concentration of all possible pairs of reflectance readings across the spectrum at given intervals is presented.
The results of the experiments demonstrate that the precision of the n.i.r. method is excellent for all four constituents, but only the calibrations for fat are sufficiently accurate to be capable of detection of metering errors of ±5% relative to the total amount of fat in the recipe.
154 citations
TL;DR: The mechanism of lectin toxicity in this instance is analogous to that known to occur in the rat, namely that the ingested lectin causes disruption of the epithelial cells of the larval midgut leading to breakdown of the transport of nutrients into these cells, and the absorption of potentially harmful substances.
Abstract: Seeds of the kidney bean (Phaseolus vulgaris) are toxic to developing larvae of the bruchid beetle (Callosobruchus maculatus), a major storage pest of many legumes. Insect feeding trials were carried out whereby the albumin and globulin protein fractions from seeds of P. vulgaris were incorporated into artificial seeds. Both fractions were shown to be toxic and to contain haemagglutinating activity, implicating the seed lectins as being involved in seed resistance. Further feeding trials using different P. vulgaris lectin preparations confirmed the toxicity of these lectins and suggested that it was the E-type lectin subunits (erythrocyte-binding) which were the major antimetabolites. Indirect immunofluorescence investigations using monospecific antisera for globulin lectins showed that the lectins, when ingested by the larvae, bound to the midgut epithelial cells. It was suggested that the mechanism of lectin toxicity in this instance is analogous to that known to occur in the rat, namely that the ingested lectin causes disruption of the epithelial cells of the larval midgut leading to breakdown of the transport of nutrients into these cells, and the absorption of potentially harmful substances. This is the first time that evidence for the mechanism of lectin toxicity has been obtained in insects.
149 citations
TL;DR: An improved method for determining the thiobarbituric acid-reactive substances (TBARS) in fish tissue has been described in this paper, where the biological sample was digested in acidic media and then separated by using specific reflux distillation.
Abstract: An improved method for determining the thiobarbituric acid-reactive substances (TBARS) in fish tissue has been described. The biological sample was digested in acidic media and then separated by using specific reflux distillation. The compounds in distillate were estimated by spectrophotometric measurement at 538 nm after the reaction with 2-thiobarbutanic acid. The operational errors, interferences and the recovery of malonaldehyde standard and TBARS from tissue sample using the described procedure have been studied. The recommended technique is simple and reproducible with a detection limit of 0.2 nmol TBARS per 10 g of tissue sample and an overall deviation of less than 7%. The recommended method has been applied satisfactorily for evaluation of rancidity studies in various fish samples.
147 citations
TL;DR: In this paper, the outer layers, comprising husks, pericarp, testa, and aleurone cells, contained the highest concentrations of total phenolic acids (0.6-0.9%) while their concentrations were considerably lower in the endosperm layers ( 0.1% or less).
Abstract: Insoluble bound phenolic acids were analysed by g.l.c. and by h.p.l.c. in eight abraded fractions of barley grain. Vanillic, p-coumaric, ferulic and diferulic acids were identified in all the fractions. Ferulic and p-coumaric acids were quantitatively the most important. The outer layers, comprising husks, pericarp, testa and aleurone cells, contained the highest concentrations of total phenolic acids (0.6–0.9%) while their concentrations were considerably lower in the endosperm layers (0.1% or less). Calculated on the basis of the cell wall content in the fractions, the highest concentration of ferulic acid was found in fractions enriched with aleurone cells while the highest concentration of p-coumaric acid was found in fractions containing high levels of husks.
145 citations
TL;DR: The use of gel-forming synthetic polymers as aids to water retention in sandy soils is an important development to assist plant growth in arid regions as discussed by the authors, however, the water storage properties of these soil conditioners are significantly affected by the nature and concentrations of dissolved salts in irrigation waters.
Abstract: The use of gel-forming synthetic polymers as aids to water retention in sandy soils is an important development to assist plant growth in arid regions. However, the water storage properties of these soil conditioners are significantly affected by the nature and concentrations of dissolved salts in irrigation waters. Moreover, the salt response of products in the three main chemical families—starch copolymers, polyvinylalcohols and polyacrylamides—is very different, emphasising the importance of detailed assays in selecting a product for a particular set of environmental conditions.
TL;DR: Based upon the above variations, arising from eating habits in the UK, together with the known large variation in glucosinolate content in cruciferous plants because of agronomic and environmental effects, it is likely that certain individuals will consume more than 300 mg total glucos inolates per day.
Abstract: Samples (174) of cabbage, Brussels sprouts, cauliflower and swede-turnip have been analysed for total and individual glucosinolate content in both the fresh and cooked form. Using data from the 1980 National Food Survey, the national mean daily intake is calculated to be 46.1 mg in fresh material, and 29.4 mg in cooked. There are large variations within the UK (for example in Scotland it is less than half that in south-west of England), between income groups and over the year. National mean daily intake figures for the glucosinolates yielding goitrogenic products such as oxazolidine-2-thiones and thiocyanate ion are 6.7 and 14.7 mg respectively; the former figure is approximately doubled in the winter months. Based upon the above variations, arising from eating habits in the UK, together with the known large variation in glucosinolate content in cruciferous plants because of agronomic and environmental effects, it is likely that certain individuals will consume more than 300 mg total glucosinolates per day. The nutritional and toxicological consequences of such an intake are unknown at present.
TL;DR: Analysis of egg albumen foams by electrophoresis showed that the basic protein lysozyme (pI 10.7) was strongly retained and clupeine enhanced foaming more effectively than Lysozyme under all conditions studied.
Abstract: Analysis of egg albumen foams by electrophoresis showed that the basic protein lysozyme (pI 10.7) was strongly retained. Addition of low concentrations (0.01–0.10% w/v) of the basic proteins clupeine (pI 12) and lysozyme to solutions (0.50% w/v) of several acidic proteins (pI 4.7–6.0) greatly improved their foaming properties at pH values between the isoelectric points. Sucrose strongly enhanced the action of the basic proteins, while not significantly affecting the foaming of the acidic proteins alone. Basic proteins did not enhance the foaming of ovalbumin and egg albumen in the absence of sucrose. Clupeine enhanced foaming more effectively than lysozyme under all conditions studied. Lysozyme was least effective near the isoelectric point of the acidic protein, where electrostatic interactions were weakest. Sodium chloride (0.1M) had a detrimental effect on the action of lysozyme.
TL;DR: The micrometeorological mass balance method has been assessed with a view to its use in the determination of ammonia (NH3) loss from grazed swards.
Abstract: The micrometeorological mass balance method has been assessed with a view to its use in the determination of ammonia (NH3) loss from grazed swards. The method involves the measurement of wind speed and the concentration of NH3 in air at different heights above the sward at its windward boundary and a position leeward of the grazed area. The flux of NH3 is calculated from these measurements and a continuous record of wind direction. Quantitative recovery of NH3 from air flows up to 10 litre min−1 was achieved using a simple trap containing dilute orthophosphoric acid and a gas dispersion tube. Wind speed measured at a height of 0.25 m at six different positions above a previously grazed sward varied by <2%. The NH3 concentration at the same positions was affected by the distance between the windward edge of the sward and the sampling position (i.e. the fetch) and by heterogeneity in the distribution of sources of NH3 (urine- or dung-affected areas). However, the normalised horizontal flux through 0.25 m (wind speedXNH3 concentration/fetch) varied by less than ±8.1% probably due to mixing through fluctuations in wind direction (approximately ±30° on the mean) as air passed over the sources of NH3 during each measurement period. Plots of wind speed or NH3 concentration versus logarithm of height indicated that each approximated a linear relationship. This facilitated the calculation of the NH3 flux per unit land area and reduced the total error to about 10%. The total loss of NH3 derived by summing losses during individual sampling intervals of 2 to 18 h within a 24 h period was essentially the same as that derived by averaging wind speeds and NH3 concentrations measured continuously over the same 24 h period. The flux of NH3 from a ryegrass sward grazed by yearling steers ranged from 0.01 to 0.14 kg N ha−1 h−1 during a 2 day grazing period within a 28 day rotation and during the 5 days following removal of animals. A pronounced diurnal variation was observed in the flux of NH3, the maximum occurring between 13.00 and 20.00 hours on each day. Rainfall and low rates of evapotranspiration reduced the flux to <0.02 kg N h−1 h−1. The total loss of NH3 during 28 days was 20.7 kg N ha−1.
TL;DR: In this paper, low molecular weight phenolic compounds were separated by high performance liquid chromatography on hydrocarbon-bonded reverse phase packings, with a water-methanol elution gradient.
Abstract: Low molecular weight phenolic compounds were separated by high performance liquid chromatography on hydrocarbon-bonded reverse phase packings, with a water-methanol elution gradient. Phenolic compounds were extracted from wine with ethyl acetate. A first extraction at pH 7 enabled isolation of neutral molecules (catechins, procyanidins, flavonols, aromatic alcohols); a second extraction at pH 2 was performed to extract phenolic acids. Successive injections of these two extracts in the chromatograph gave the distribution of the different phenolic compounds in the wine under analysis. Analytical data are given for low molecular weight phenolic compounds present in young red Bordeaux wines from different vine cultivars.
TL;DR: In this paper, the authors measured the rate of infusion of caffeine into distilled water from medium roast Kenyan Arabica coffee beans and from eight sieved fractions of the ground beans at 25.8°C.
Abstract: Measurements have been made of the rate of infusion of caffeine into distilled water from medium roast Kenyan Arabica coffee beans and from eight sieved fractions of the ground beans at 25.8°C. The first-order rate constants increased dramatically as the particle size decreased. For one of the size fractions the rate constants were then measured at various temperatures up to 84.1°C and were found to rise eight-fold over this temperature interval. The partition coefficients of caffeine between ground beans and water were also determined. These results, interpreted by a new steady-state theory of extraction, show that the rate-determining step in the infusion is diffusion of caffeine through the swollen coffee particles. The low magnitude of the diffusion coefficient and its high activation energy demonstrate that caffeine diffusion within the bean particles is a hindered process.
TL;DR: Thermograms of myofibrillar tissue from pale, soft, and exudative (PSE) pork were compared to tissue from normal pork by differential scanning calorimetry at pH 5.4, and the area of the low temperature myosin segment was shown to be reduced by about 50% in PSE pork, as compared to normal pork.
Abstract: Myofibrillar tissue from pale, soft, and exudative (PSE) pork was compared to tissue from normal pork by differential scanning calorimetry at pH 5.4. Thermograms of myofibrillar tissue from normal pork were characterised by three major peaks with temperature maxima at 58 and 66°C, associated with myosin denaturation, and at 78°C, associated with actin denaturation. In thermograms of PSE pork, the peak at 58°C was markedly reduced, and appeared as a shoulder. When the thermograms were divided into segments corresponding to the three major peaks, the area of the low temperature myosin segment was shown to be reduced by about 50% in PSE pork, as compared to normal pork. This indicates approximately 50% denaturation of the least thermostable parts of the myosin molecule. The more thermostable parts of the myosin molecule were largely unaffected, as was actin.
TL;DR: In this article, the same 1976 wines were assigned quality ratings by Masters of Wine (MW), and the major aroma difference between the wines was attributed to variation in the intensity of the green bean/green olive character by canonical variates analysis (CVA) of the aroma descriptor ratings across wines.
Abstract: Twenty-four wines from four communes in Bordeaux were evaluated by descriptive analysis by trained assessors. The same 1976 wines were assigned quality ratings by Masters of Wine (MW). The major aroma difference between the wines was attributed to variation in the intensity of the ‘green bean/green olive’ character by canonical variates analysis (CVA) of the aroma descriptor ratings across wines. The CVA of the flavour by mouth ratings showed the wines to be discriminated primarily on the basis of astringency and bitterness. By multivariate analysis of variance across regions, and by examination of the configurations derived from the CVA across wines, it was shown that the wines did not vary significantly between communes. No significant difference between the wines in quality ratings of the MWs was found.
TL;DR: The predicted metabolisable energy (ME) value of commercial rapeseed or canola meal for poultry was found to be numerically close to the determined value when the available carbohydrate value was reduced to 35% of the observed value.
Abstract: Cotyledons from 11 varieties of rapeseed and canola seed were extracted with hexane and analysed for tannins, α-amylase inhibition value, starch and available carbohydrate by conventional methods. The sinapine content (total sinapic acid esters plus free sinapic acid) was determined by a spectrophotometric method. Samples of soya bean cotyledons, high-tannin sorghum grain and commercial rapeseed and canola meals were also analysed for comparison. Sinapine in rapeseed and canola cotyledons was measured at mean levels of 2.67 and 2.85% respectively. Tannins were detected in these cotyledons but only at low levels. The α-amylase inhibition values were also low or negative. Starch was detected in negligible amounts, and available carbohydrate at 13–14%. The predicted metabolisable energy (ME) value of commercial rapeseed or canola meal for poultry was found to be numerically close to the determined value when the available carbohydrate value was reduced to 35% of the observed value.
TL;DR: Myrosinase activity in partially purified extracts of 12 cruciferous vegetables and an acetone powder preparation of Sinapis alba L. alba (white mustard) was determined by the initial rate of glucose formation from glucosinolate hydrolysis using a coupled assay, revealing that the ascorbate concentration necessary to promote maximal activity varied with species.
Abstract: Myrosinase activity in partially purified extracts of 12 cruciferous vegetables and an acetone powder preparation of Sinapis alba L. (white mustard) was determined by the initial rate of glucose formation from glucosinolate hydrolysis using a coupled assay. Of the species studied Raphanus sativus L. (radish, 12.8±0.7 μmol min−1g−1 powdered tissue) had the greatest myrosinase activity, and Brassica campestris L. ssp. rapifera (turnip) and Nasturtium officinalis R.Br. (watercress) (0.6±0.1 and 0.8±0.03 μmol min−1g−1 powdered tissue respectively) the least. The sub-species of Brassica oleracea studied all had similar myrosinase activity (ca 2.5±0.2μmolmin−1g−1 powdered tissue) except B. oleracea L. var. gemmifera D.C. (Brussels sprouts) and B. oleracea L. var. capitata L. (white cabbage) which had higher activities (7.6±0.1 and 5.2±0.2μmol min−1g−1 powdered tissue respectively). The effect of ascorbate concentration upon the myrosinase activity of six of the crucifers studied and the white mustard preparation, revealed that the ascorbate concentration necessary to promote maximal activity varied with species. A concentration of 0.9mM ascorbate maximally activated radish and turnip myrosinase, while red cabbage, watercress, white mustard and Brussels sprouts were maximally activated at 2.0, 3.0, 5.0 and 0.7–1.0mM ascorbate respectively. Two peaks of maximal myrosinase activity, occurring between 0.9 and 1.0mM and at 3.0mM ascorbate, were found for B. oleracea L. var. botrytis L. subvar. cauliflora D.C. (cauliflower).
TL;DR: In this paper, the effect of exogenous short-chain n-alcohols on the concentrations of main aroma components in mature intact Red Delicious apples and aged apple tissue discs has been studied.
Abstract: The effect of exogenous short-chain n-alcohols on the concentrations of main aroma components in mature intact Red Delicious apples and aged apple tissue discs has been studied. Storage of intact apples in an atmosphere containing ethanol vapours for 24 h resulted in a more than threefold increase in the sum of ethyl ester concentrations. The simplified model of tissue discs was applied to examine the influence of various ethanol concentrations on rate and time course of ester formation. On supplying a range of n-alkan-1-ols and 2-keto valeric acid in equimolar amounts to the discs, maximum conversion into esters was found with butanol and pentanol. The possibility of an in vivo aroma enrichment before processing of fruits is discussed.
TL;DR: Both trypsin and chymotrypsin inhibitor contents appeared to be independent of crude protein content and other seed characteristics, and in both species these protease inhibitors were largely unaffected by dry heat but were rapidly denatured by autoclaving.
Abstract: Eighteen pea and five field bean varieties were analysed for trypsin inhibitor activity. Considerable variation was found between pea varieties, the values ranging from 0.15 to 4.62 TIU mg−1 under the assay conditions used. However, all the pea varieties, with the exception of Progretta and Maro, had a lower trypsin inhibitor content than the average value (1.49 TIU mg−1) obtained for the field bean varieties. The same varieties were also examined for chymotrypsin inhibitor activity and again considerable inter-varietal variation was found. Chymotrypsin inhibitor activity was significantly higher for all the pea varieties, with the exception of the variety Minerva, than that found for the field bean varieties. Both trypsin and chymotrypsin inhibitor contents appeared to be independent of crude protein content and other seed characteristics, and in both species these protease inhibitors were largely unaffected by dry heat but were rapidly denatured by autoclaving. The significance of these results with respect to the potential of improving nutritive value by plant breeding are discussed.
TL;DR: Pea globulins, vicilin and legumin were isolated by chromatography on DEAE Sepharose and Ultrogel ACA 34 and the purity was verified by immunoelectrophoretic and ultracentrifuge analysis.
Abstract: Pea globulins, vicilin and legumin were isolated by chromatography on DEAE Sepharose and Ultrogel ACA 34. The procedure was carried out on a preparative scale and used to purify about 5 g of each globulin for a separation cycle. The purity of the vicilin and legumin was verified by immunoelectrophoretic and ultracentrifuge analysis.
TL;DR: Good quality fish sauce was produced from anchovies (Stolephorus spp.) that had been allowed to autolyse at pH 4 and low salt concentration as discussed by the authors, and this rapidly produced fish sauce had a lower level of volatile base and acid, and a better balanced composition of essential amino acids than a first grade commercial fish sauce.
Abstract: Good quality fish sauce was produced from anchovies (Stolephorus spp.) that had been allowed to autolyse at pH 4 and low salt concentration. After an initial phase of rapid autolysis, the samples were neutralised, and salt was added to the normal level (250 g kg−1) before the fish sauce was separated by suction. By this method fish sauce with acceptable flavour could be produced after 2 months, whereas the normal production time is more than 6 months. This rapidly-produced fish sauce had a lower level of volatile base and acid, and a better balanced composition of essential amino acids than a first grade commercial fish sauce.
TL;DR: In this paper, the authors used 5 mm transverse slices incubated at 32oC in a medium containing 0.1M phosphate buffer, pH 7.0, 0.02M KNO3, 30 ml litre−1 propan-1-ol, and 0. 1 ml liter−1 Triton X-100.
Abstract: Assay conditions in vivo for determining nitrate reductase activity (NRA) in shoot and root tissues of winter barley (Hordeum vulgare L. cv. Igri) were studied. The composition, pH and temperature of the incubation medium, and the size of leaf slice were varied. Maximum leaf NRA was obtained with 5 mm transverse slices incubated at 32oC in a medium containing 0.1M phosphate buffer, pH 7.0, 0.02M KNO3, 30 ml litre−1 propan-1-ol and 0.1 ml litre−1 Triton X-100. The optimum assay conditions for roots were similar to those for leaves, except that the pH was 7.5. There was negligible nitrite reductase activity in leaves incubated in the dark.
TL;DR: The seeds of baobab and the tubers of tigernut were analysed chemically for their proximate composition and amino acids and the level of antinutritive substances, such as tannin and tryptic inhibitors, in the raw vegetables were reduced by soaking or boiling.
Abstract: The seeds of baobab (Adansonia digitata L.) and the tubers of tigernut (Cyperus esculentus L.) were analysed chemically for their proximate composition and amino acids. The tubers contained 47.9% digestible carbohydrates, 32.8% oil and 3.8% crude protein. The baobab seeds contained 24.1% digestible carbohydrate, 29.7% oil and 28.4% crude protein. A mixture of the vegetables was prepared from three parts of the tigernuts and one part of baobab seeds, by weight, such that a 10% crude protein meal was obtained. The chemical score of the mixed vegetable was 51%, based on limiting amino acids, i.e. those which contain sulphur. The level of antinutritive substances, such as tannin and tryptic inhibitors, in the raw vegetables were reduced by soaking or boiling.
TL;DR: Three common market-grade culinary vegetable oils—groundnut oil, cottonseed oil and coconut oil—in preserving the internal quality of freshly laid eggs coated with them and stored under tropical room conditions of 25–32°C and 40–85% r.h. for 36 days are evaluated.
Abstract: The study evaluates the efficacy of three common market-grade culinary vegetable oils—groundnut oil, cottonseed oil and coconut oil—in preserving the internal quality of freshly laid eggs coated with them and stored under tropical room conditions of 25–32°C and 40–85% r.h. for 36 days. All three vegetable oils significantly (P 0.05) improvement over untreated eggs.
TL;DR: An automated method for the analysis of cyanide in cassava and cassava products is described in this article, where a wide range of free (nonglycosidic) or bound (cyano-substituted glycosides) cyanides (0.4-40 μg HCN ml−1) can be assayed in the extracted solutions.
Abstract: An automated enzymic method for the analysis of cyanide in cassava and cassava products is described. A total of 300 analyses a day can be handled easily. A wide range of free (nonglycosidic) or bound (cyano-substituted glycosides) cyanides (0.4–40 μg HCN ml−1) can be assayed in the extracted solutions. The upper limit of detection for the bound cyanide can easily be increased by another three-fold by assaying it under partial hydrolysis conditions. The two enzymic methods, manual and automated on Technicon's AutoAnalyzer, agreed well for the free and the bound cyanide in the leaf and the peeled storage root samples.
TL;DR: The albumin fraction of the cotyledons of Pisum contains two major polypeptides which together make up 34% (17% each) of the total albumin fractions, which could be significant factors in determining the nutritional value of pea seed proteins.
Abstract: The albumin fraction of the cotyledons of Pisum contains two major polypeptides which together make up 34% (17% each) of the total albumin fraction. Both of these albumins (Mr∼8000 and ∼22000) are cotyledon specific proteins. In many Pisum lines the Mr∼22000 fraction resolves into two components on Na-dodecylsulphatepolyacrylamide gels. The Mr∼8000 polypeptide was broken down during germination and early seedling growth, indicating that it functions as a storage protein, while the Mr∼22000 polypeptides were degraded relatively slowly. The level of both of these polypeptides was markedly reduced under sulphur deficiency conditions, the Mr∼22000 components being affected to a lesser extent than the Mr∼8000 component. Consistent with this, when [35S]sodium sulphate was injected into the pedicel of control plants during seed development and albumins were isolated at seed maturity, polypeptides of Mr∼8000 and ∼22000 together accounted for a major proportion of the radioactivity in the total albumin fraction. The abundance and relatively high sulphur content of these two albumins could be significant factors in determining the nutritional value of pea seed proteins.
TL;DR: In this article, the cell walls of maize, barley, Italian ryegrass, wheat bran, lucerne and red clover were subjected to low voltage pyrolysis-mass spectrometry.
Abstract: Cell walls of plant parts of maize, barley, Italian ryegrass, wheat bran, lucerne and red clover were subjected to low voltage pyrolysis-mass spectrometry. The ion intensity at m/z 120, which is characteristic of p-coumaric acid, was significantly correlated (r=0.99) with the p-coumaric acid content of the walls; the ion intensity at m/z 150, characteristic of ferulic acid, was present in the spectra of the graminaceous walls. Factor analysis of the pyrolysis-mass spectra indicated that some, at least, of the p-coumaric and ferulic acid constituents of the walls are bound to pentosans, and suggested that not all the aromatic constituents of the walls are bound to polysaccharides.