bluuebunny/crossref_metadata_2025 huggingface dataset:
Profile of fibre composition in lucerne (Medicago sativa) hay and rumen digesta as influenced by particle size and time after feeding
Authors: Jung Hans‐Joachim G , Åman Per , Graham Hadden
Published: October 2006

The chemical composition of fibre from lucerne (Medicago sativa L) hay and rumen digesta from a cow fed the hay, as well as the variation in fibre composition due to particle size and time post‐feeding for the digesta, was examined. Neutral sugar residues accounted for the greatest proportion of the fibre in all samples. The feed contained equal amounts of uronic acid residues and Klason liynin, while in the digesta uronic acid residue contents were decreased and Klason lignin levels were increased. Esterified phenolics accounted for less than 0.5 % of the fibre in all samples. Glucose was the primary sugar residue in the fibre, but xylose levels increased substantially in the digesta. The levels of other sugar residues declined in the digesta relative to the feed. p‐Coumaric and ferulic acids were the major esterified phenolics, and ferulic acid levels declined relative to the total phenolic acids in the digesta. The degree of variation in composition among particle size fractions or in digesta samples with time afer feeding were small relative to those observed between the feed and digesta. Invitro degradability reflected differences in fibre composition, with a large difference between lucerne hay and rumen digesta, but only minor differences among digesta samples collected from different times after feeding.
lipid, saccharide, protein, phenolic acid and saponin contents of four market classes of edible dry beans as influenced by soaking and canning
Authors: Drumm Terri D , Gray J Ian , Hosfield George L , Uebersax Mark A
Published: October 2006

The effects of soaking and canning on the lipid, saccharide, protein, phenolic acid and saponin contents of four market classes (navy, dark red kidney, pinto and black turtle soup) of dry beans (Phaseolus vulgaris L) were determined. These compounds are potential flavour precursors. Significant (P < 0.05) decreases in the content of the saccharide, non‐protein nitrogen, phenolic acid and saponin contents occurred with processing. Lipid composition und totul nitrogen content of the raw and canned beans were not signifiiantly (P < 0.05) different. Leuching and thermal degradation of these components contributed to the decreases in their content.
Effects of germination on the chemical composition of Glycine and Phaseolus beans
Authors: Lee Cheang Kuan , Karunanithy R
Published: October 2006

The effects of germination on total protein and amino acids, and phytic acid of beans of Glycine max L, Glycine hispida L, Phaseolus radiatus L and Phaseolus angularis L were studied. The increase in total crude protein content was > 21% for Glycine beans and 8–15% for Phaseolus beans. There was a marked increase in the total essential amino acids of Glycine max (76%) and Phaseolus radiatus (52%). A smaller increase was observed for Phaseolus angularis (25%) and Glycine hispida (3%). The phytic acid contents of the beans were drastically reduced (< 0.2%), mainly due to leaching into the soak water. Total ash content showed a decrease, too, also due to leaching; the loss of potassium was very high whereas losses of the divalent metals, calcium, iron and magnesium, were only moderate, probably because of the ability of divalent cations to bind to protein to form proteincation‐phytate complexes and also because divalent salts of phytic acid are insoluble at moderate to high pHs.
The numbers of epiphytic bacteria on grass at ensilage on commercial farms
Authors: Rooke John A
Published: October 2006

The numbers of lactic acid bacteria and enterobacteria on herbage at the silage pit on commercial farms in Durham and Northumberland were determined in 1987 and 1988. The mean number of lactic acid bacteria were higher (P <0.01) in 1987 (second silage cut) than in 1988 (first silage cut); mean values were 5.46 and 4.85 log10 colony‐forming units g−1 herbage, respectively, when enumerated on MRS agar. In 1988, when Rogosa agar was used to enumerate the lactic acid bacteria in addition to MRS agar, the numbers of lactic acid bacteria recovered were substantially less than on MRS agar. These results are discussed in relation to epiphytic lactic acid bacteria numbers reported in the literature and to recommended application rates of inoculant‐type silage additives. The epiphytic enterobacteria did not differ in numbers between years and had a mean value of 4.76 log10 colonyforming units g−1 herbage.
Effect of differences in variety and dry milling of maize on textural characteristics of Ogi (fermented maize porridge) and Agidi (fermented maize meal)
Authors: Osungbaro Taiwo O
Published: October 2006

Samples of ogi from jive maize varieties prepared in distilled or souring water were assessed for their amylograph pasting viscosities. Textural attributes for firmness of agidi similarly prepared from the five maize varieties were evaluated by sensory evaluation. Amylose content of the maize varieties varied between 29 and 34%. The FARZ‐27 maize variety appeared to have the most suitable pasting viscosities for ogi and best gelling characteristics for agidi manufacture, as measured on the Brabender amylograph and by sensory evaluation. Use of ogi souring water in ogi preparation resulted in decreased amylograph pasting viscosities. Agidi prepared using souring water had lower sensory scores for firmness than samples prepared in distilled water. Maize was dry milled and fermented for 0, 2, 4 or 6 days. The implications of this method of preparation for the textural qualities of ogi and agidi are discussed.
Variations of the chemical composition of clonal black tea (Camellia sinensis) due to delayed withering
Authors: Owuor Philip O , Orchard John E , Robinson Janet M , Taylor Sarah J
Published: October 2006

The chemical composition of black teas (Camellia sinensis L) varies when the green leaf from which they are manufactured is withered physically to the same degree but for different periods. Caffeine contents progressively increase with prolonged withering time whereas theaflavins decrease due to prolonged withering. Although the sums of group I and group II volatile flavour compounds (VFC) decrease with prolonged withering time, the flavour index (expressed as group II VFC/group I VFC) increases due to prolonged withering. No significant changes were noted in the thearubigin levels with variation in withering time, but the tasters' evaluations were at a maximum for teas withered for 14 h. Subsequently the evaluation decreased with longer withering times.
Variations in the leaf standard, chemical composition and quality of black tea (Camellia sinensis) due to plucking intervals
Authors: Owuor Philip O , Odhiambo Herman O , Robinson Janet M , Taylor Sarah J
Published: October 2006

Green leaf standard, chemical composition and quality of black tea (Camellia sinensis (L) O Kuntze) change with plucking intervals. Long plucking intervals lead to poor leaf standard with a lot of mature leaves and lower theaflavins, the sum of volatile flavour compounds imparting a sweet flowery aroma (group II volatile flavour compounds), caffeine contents and tasters' evaluations of black tea. The sum of volatile flavour compounds imparting inferior, grassy, green flavour (group I volatile flavour compounds) to tea, however, increases with long plucking intervals.
Long chain phenols—the thermal and oxidative deterioration of phenolic lipids from the cashew (Anacardium occidentale) nut shell
Authors: Tychopoulos Vasiliki , Tyman John H P
Published: October 2006

The thermal and oxidative deterioration of a mixture comprising the (15:0)‐, (15:1)‐, (15:2)‐ and (15:3)‐cardanols has been investigated by HPLC analysis. In air the oxidative deterioration is dependent on reaction time, unsaturated structure and temperature, being significant at 180°C and fairly extensive at 240°C. The reactivity of the constituents follows the sequence(15:3)‐cardanol > (15:2)‐cardanol > (15:l)‐cardanol > (15:0)‐(cardanol‐3‐pentadecylphenol). At 180°C, replacement of the aerial atmosphere by nitrogen retards the deterioration although in the upper range an inert atmosphere has only a marginal effect. The mixture and the individual cardanol constituents behave similarly. The results are relevant to distilllation procedures for purifying cardanol, to other unsaturated lipid systems and to the technical processing of the product known as technical cashew nut‐shell liquid from the cashew nut Anacardium occidentale L. Rate studies indicate that first order kinetics prevail in a nitrogen atmosphere. In air a second order rate of reaction was not always observed.
Effects of glyceryl monostearate and α‐amylase supplements on rheological and breadmaking properties of medium protein wheat flour
Authors: Bajwa Usha
Published: October 2006

The rheological and breadmaking properties of medium protein wheat flour as influenced by increasing levels of glyceryl monostearate (GMS) with and without optimal α‐amylase supplements were investigated. The paste viscosity of flour was considerably reduced by optimal wheat malt, fungal and bacterial α‐amylase supplements. However, the paste viscosity, apparent gelatinisation temperature at 20 AU and peak viscosity temperature were appreciably increased with increasing level of GMS. The dough consistency decreased depending upon the source of α‐amylase and the concentration of GMS. The use of GMS and α‐amylases singly or together improved dough handling and loaf volume. Incorporation of GMS imparted a softer texture to the loaves as measured with an lnstron instrument, but they turned crumbly during storage. Tendency to crumbliness decreased on supplementation with α‐amylases. GMS at a concentration of 10–20 g kg−1 along with optimal α‐ amylase supplements could successfully be used to obtain improved loaves with better physical characteristics and softer crumb.
Headspace gas analysis of volatile hydrocarbons as a tool for the determination of the state of oxidation of foods stored in sealed containers
Authors: Löliger J
Published: October 2006

Headspace gas analysis for short chain hydrocarbons (pentane and ethane) is proposed as a tracer for following the oxidative degradation during storage of foods contained in sealed containers. This type of analysis could be used for foods ranging from oils and emulsions to frozen meats and dehydrated cereals. Correlation between sensory and analytical evaluation must be established for each individual product. Headspace gas analysis of a great variety of products was conducted and very good correlation between sensory and chemical analysis was obtained.
Effects of alcohol extraction and heat treatment on the utilisation of soya bean protein by growing rats and pigs
Authors: Hancock Joe D , Peo Ernest R , Lewis Austin J , Chiba Lee I , Crenshaw Joe D
Published: October 2006

Three experiments were conducted to determine the effects of alcohol extraction and heat treatment on the nutritional quality of soya bean protein. In experiment 1, 144 weanling rats were used to determine the effects of different alcohol and heat treatments of defatted raw soya bean flakes (SF) on protein utilisation. Treatments were: (1) solvent extraction (water or 50% alcohol/water mixtures of methanol, ethanol and n‐propanol), and (2) heat treatment (no heat, heating before extraction and heating after extraction). Solvent extraction consisted of soaking the SF in the solvents for 48 h. Heat treatment was autoclaving for 15 min at 121°C and 1.1 kg cm−2 steam pressure. Regardless of solvent used to extract the SF, rats fed SF that had been autoclaved grew faster (5.3 versus 3.4 g day−1)and were more efficient (gain:feed, 0.35 versus 0.27) than rats fed SF that had not been autoclaved (P < 0.001). Soya bean flakes that had been autoclaved before extraction supported rates and efficiencies of gain that were 16% and 12% greater (P < 0.005 and P < 0.001, respectively) than SF autoclaved after extraction. Alcohol‐extracted SF' supported greater rates (P < 0.03) and efficiencies (P < 0.002) of gain than water‐extracted SF. In experiment 2, 720 weanling pigs were used in a growth assay and, in experiment 3, 30 pigs were used in a nitrogen balance study. Treatments used in both experiments were: (1) defatted raw SF, (2) autoclaved SF, (3) ethanol‐extracted SF, (4) SF autoclaved before extraction with ethanol, and (5) SF autoclaved after extraction with ethanol. Ethanol extraction of the unheated SF resulted in an improved growth rate (74 versus 15 g day−l, P < 0.005) and nitrogen retention(51.5 versus 37.3%; P < 0.001) when compared with the raw unextracted SF. However, ethanol extraction in addition to autoclaving did not improve protein quality over autoclaving only (P > 0.05). Alcohol extraction improves the utilisation of protein from defatted raw SF by rats and pigs, but changes in protein utilisation due to alcohol extraction of properly heated SF are minimal.
Measuring lignin in human and rat faeces
Authors: Kraus Richard J , Marlett Judith A
Published: October 2006

The two objectives of these experiments were to evaluate solvent systems for removal of artefact lignin from crude faecal lignin and to determine the effect of the solvents on the neutral sugar content of faeces. Four human and three rat faecal samples collected during different dietary intakes were extracted with a 1:1 (v) mixture of ethyl acetate and acetic acid (EAc) or with water followed by EAc. Crude lignin (CL), determined as the insoluble material after a Saeman acid hydrolysis, was measured in the faeces and its various fractions, and compared with Klason lignin, the residue after sulphuric acid treatment of acid detergent fibre, and with permanganate lignin. EAc extraction significantly reduced the CL content of all samples. Water extraction alone generally did not lower faecal CL contents as much as did EAc extraction. EAc extraction alone, or in combination with water, of two rat faecal samples indicated zero CL, consistent with the zero CL content of dietary cellulose; in all other samples, human cellulose and wheat bran and rat wheat bran faeces, Klason lignin and permanganate lignin were lower than CL. The two‐step extraction did remove more nitrogen than EAc alone. EAc extracted 1 to 2% of the faecal total neutral sugars and water extracted 2–5% total neutral sugars from six of the samples; 11 and 35% respectively of total neutral sugars were extracted from fibre‐free human faeces. Analysis of cellulose‐containing rat faeces with and without cholesterol and cholic acid suggested that sterols or their microbial metabolic products, as well as nitrogenous compounds, were part of the artefact lignin.
Problems with ytterbium precipitation as a method for determination of plant phenolics
Authors: Lowry J Brian , Sumpter E Anne
Published: October 2006

The most abundant secondary compounds of higher plants, in both diversity and level of occurrence, are phenolic in nature. They exert a wide range of biological effects that are increasingly seen to be important in plant‐animal and plant‐pathogen interactions. A convenient initial classification is to distinguish those that precipitate protein, tannins, from those that do not. Tannins can best be analysed by one of the protein precipitation methods, but the estimation of total (tannin and non‐tannin) phenolics in plant extracts presents problems. Several methods are available but they depend upon chromogenic reagents that may give different responses with different compounds. Results have to be given in terms of a standard (often tannic acid) that may or may not be appropriate in the particular case. Satisfactory calibration can be obtained for repeated analyses of the same commodity or species, but this is problematic when investigating unknown materials. A recent paper (Reed et al 1985) describes a method for determination of plant phenolics (both tannin and non‐tannin) by precipitation with trivalent ytterbium. For the reasons outlined above, such a direct gravimetric method has major attractions as it avoids the problem of the use of possibly inappropriate standards. It can now be reported that this method is unsuitable for the determination of total phenolics. Following some considerable practical problems with carrying out the method, it was applied to a number of pure compounds. This showed that many of the common non‐polymeric compounds, including the most common flavonol glycoside, rutin, do not precipitate quantitatively under the conditions described. Some phenolics form no precipitate when present at a level that would correspond to 40% of the plant dry weight.
Nutritive and economic value of guinea fowl (Numida meleagris) production in developing countries
Authors: Agwunobi L Nnabenyi , Ekpenyong Thomas E
Published: October 2006

Eighty broiler guineafowls (Numida meleagris) and 80 broiler chickens (Gallus gallus domesticus) were raised from 1 day old to 12 weeks on the same starter and finisher diets. Weight gain, feed consumption, feed efficiency, cost of production, nutritive quality and mortality were compared between the two types of bird. It was found that the broiler chickens consumed nearly twice as much feed, gained more than twice as much weight and had significantly (P < 0.01)better feed efficiency than the guineafowl. It cost significantly (P < 0.01)less to produce a kilogram of flesh from the broiler chickens than from the guineafowls. However, the guineafowl carcass excelled in nutritive quality. It had significantly (P < 0.05)more protein and ash, particularly calcium and phosphorus. The fat content of the guineafowl carcass was significantly (P < 0.05)less than that of the chickens. Mortality was less for the guineafowl than for the chickens.
Chemical studies on mixed‐linked β‐glucans in hull‐ less barley cultivars giving different hypocholesterolaemic responses in chickens
Authors: Bengtsson Staffan , Åman Per , Graham Hadden , Newman C Walter , Newman Rosemary K
Published: October 2006

The structure of mixed‐linked β‐glucans was studied in three hull‐less barley (Hordeum vulgare L) cultivars, Arizona, a waxy‐starch genotype with high mixed‐linked β‐glucan content giving hypocholesterolaemic responses in chickens, and two genotypes with normal mixed‐linked β‐glucan contents. One of these, Washonupana, also a waxy‐starch type, reduces blood cholesterol whereas the other, Franubet has no effect. When a ground sample was suspended in water, Arizona and Washonupana gave highly viscous slurries whereas Franubet gave low viscosity. This viscosity was greatly reduced by addition of endo‐β‐glucanase. Arizona gave the highest yield of water‐soluble mixed‐linked β‐glucans, while the ratio of 1.3 to 1.4 linkages (1:26) was very similar in this fraction for all barleys. 13C‐NMR indicated that these water‐soluble fractions from all three barleys had essentially the same repeating sequence patterns and that 1.3 linkages occurred singly. Gel filtration established that the water‐soluble mixed‐linked β‐glucans in Washonupana had the highest average molecular weight and Franubet the lowest. The hypocholesterolaemic responses observed in chickens were attributed to viscous conditions within the gastrointestinal tract, and this was a function of the content and molecular weight of the mixed‐linked β‐glucans and of endogenous β‐glucanase activity in the barleys.
Upgrading quality of dried tomato: Effects of drying methods, conditions and pre‐drying treatments
Authors: Olorunda A O , Aworh O C , Onuoha C N
Published: October 2006

Rate of moisture removal increased with temperature in tomato (Lycopersicon esculentum Mill) pieces dried, using through‐flow and cross‐ flow air patterns, in a pilot‐scale cabinet dryer at 60, 70 and 80°C with an air velocity of 1.75 ms−1. Moisture removal was faster for through‐flow than for cross‐flow drying at each temperature. Lower moisture content and improved appearance were achieved by dipping, for 3 min, tomato slices in NaCl (300 g litre−1) or in a solution containing 9 g litre−1 potassium metabisulphite and 100 g litre−1 NaCl, or by adding NaCl (33 g kg−1) to tomato slurry prior to sun or oven drying. Nigerian‐type sauces made from pretreated oven‐dried tomatoes were considered acceptable, though inferior to that made from drum‐dried tomatoes.
Anisotropy of apple parenchyma
Authors: Khan Ali A , Vincent Julian F V
Published: October 2006

Parenchyma of a range of apple varieties was either sectioned in a cryotome and observed under a light microscope, or freeze dried and viewed under a scanning electron microscope. The morphology of the material varied according to the direction from which it was viewed. This phenomenon, known as anisotropy, increased from the outside to the inside of the cortex. The periphery consisted of radially flattened or spherical cells (50 μ dia) with spherical intercellular spaces. Towards the interior the cells increased in size (300 μ dia) and were radially elongated, organised into radial columns. In between these columns were radially elongated spaces up to 3 mm long and 100–200 μ wide. The aspect ratio of the intercellular spaces increased almost linearly from outside to inside (1 to 9, depending on variety). The volume fraction of the cells similarly increased.
Digestion in sheep of diets containing naked oats or barley
Authors: Martin Pamela A
Published: October 2006

Four sheep fitted with cannulas in the rumen and proximal duodenum were used to compare the digestion of two diets in an experiment conducted according to a two‐period reversal design with 28‐day periods. Chopped hay (400 g day−1) was given with either 500 g barley and 120 g soya bean meal day−1or 500 g naked oats and 100 g soyabean meal day−1. Digestion in the stomach, duodenal flow and faecal excretion of chemical constituents were measured using chromium‐mordanted straw as a marker. As a consequence of compositional differences between the cereals, daily intakes of neutral detergent fibre (NDF), acid detergent fibre (ADF) and total fatty acids were 331 and 295, 172 and 161, and 12·1 and 36·9 g for the barley and the naked oats diet respectively.

Dietary substitution of naked oats for barley reduced (P < 0.05) the extents to which NDF and ADF were digested in the stomach. There was an associated decrease (P < 0.05) in the proportion of acetic acid in the rumen volatile fatty acids, and the proportion of propionic acid tended to be increased. Rumen ammonia N concentration was reduced (P < 0.05). Duodenal passage of total N and non‐ammonia N was increased (P < 0.001), as was that of total fatty acids (P < 0.05),when naked oats were given but there were no significant differences between diets in N or total fatty acid digestibilities in the total tract.

The results show that dietary substitution of naked oats for barley can alter ruminal digestion through effects that appear to derive from the associated increase in lipid intake.
Use of an HPLC photodiode‐array detector in a study of the nature of a black tea liquor
Authors: Bailey Richard G , McDowell Ian , Nursten Harry E
Published: October 2006

The non‐volatile, water‐soluble constituents of black tea were studied by using reversed‐phase HPLC with a photodiode‐array detector, using a linear gradient developed for this purpose. The data generated by this detector from one injection of a black tea liquor allowed information on the nature and purity of the constituents to be obtained. The following constituents were identified by the spectral data and the retention times given by reference compounds: caffeine, theobromine, (−)‐epicatechin gallate, (−)‐ epigallocatechin gallate, gallic acid, chlorogenic acid (5‐O‐caffeoylquinic acid), p‐coumaroylquinic acid, quercetin 3‐glucoside, quercetin 3‐rhamnosylglucoside, kaempferol 3‐rhamnosylglucoside, and theaflavin digallate. Other peaks were classified by spectral data, but without reference compounds conclusive assignments could not be made. Finally, a group of peaks could be classified as coloured phenolic pigments, and tentatively assigned as thearubigins.
A comparison of the deterioration in quality of freeze dried flesh of halibut (Hippoglossus stenolepis) during storage in air and nitrogen at low water activities
Authors: Koizumi Chiaki , Ohshima Toshiaki , Wada Shun
Published: October 2006

Freeze dried halibut (Hippoglossus stenolepis Schmidt) flesh was stored in air and in nitrogen for 200 days at 25°C and Aw 0.52, and the deterioration in quality was examined. The brown discoloration occurring in the early stages of storage progressed faster in the nitrogen‐ than in the air‐stored sample. Phospholipids content decreased and free fatty acids increased during storage indicating enzyme hydrolysis of the phospholipids. Lipid oxidation occurred more rapidly in the air‐ than in the nitrogen‐stored samples. In‐vitro digestibility decreased at a similar rate in both the air‐ and the nitrogen‐stored samples. Available lysine and lysine contents of the samples decreased more rapidly in nitrogen than in air for up to 100 days of storage. These results indicated that in the early stages of storage of freeze dried halibut flesh quality, deterioration in terms of brown discoloration and the loss of lysine and available lysine occurs more rapidly in nitrogen than in air.
Postharvest incidence of aflatoxins in Linum usitatissimum seeds
Authors: Sahay S S , Prasad T , Sinha K K
Published: October 2006

Linseed (Linum usitatissimum L), collected from kothi and gunny bag, had a total of 18 fungal species. Aspergillus spp were the more frequent and accounted for more than 40 % of the total count. The gunny bag storage system exhibited higher dominance of A flavus than occurred in the kothi system. Out of 251 isolates screened, 44 % were toxigenic and produced different components of alfatoxins in the range 105–3000 μg litre −1. Of 105 samples extracted for the natural presence of alfatoxin, 46 had aflatoxin contamination. The concentration of alfatoxin B1 in contaminated samples ranged from 120 to 810 μg kg−1.
Suitability of various australian wheats for chinese‐style steamed bread
Authors: Lin Zuo‐Ji , Miskelly Diane M , Moss H John
Published: October 2006

Three methods of preparation of steamed bread on a laboratory scale were evaluated to determine the one most suitable for discriminating between flour samples. The preferred method was then applied to a number of wheat varieties at different protein levels to select the most suitable ones for this product, and to determine the key analytical parameters of the most suitable flour.

Flour colour and protein content appeared to be more important than other physical and chemical properties. Flour samples with high protein content (greater than 12%) and strong doughs gave bread with a wrinkled surface and dark colour, whereas low protein (less than 10%) soft wheat flours gave poor texture and eating quality, although the surface was smooth. It is suggested that flours of medium protein content (10–12%) and medium dough strength are the most suitable for steamed bread. Processing conditions affected steamed bread quality. Blending of high protein hard strong wheats with soft weak wheat could be practical for preparing flour for steamed bread.
A simple glutenin turbidity test for the determination of heat damage in gluten
Authors: Hay Rob L , Every Dale
Published: October 2006

A quantitative test specific to heat damage in wheat gluten has been developed. The test is simple and rapid, allowing a trained operator to analyse batches of samples, and interpret the results, in under 1 h. The glutenin turbidity test measures the loss in solubiliity of one class of proteins, acetic acid soluble glutenin. The soluble glutenin was isolated as a finely dispersed precipitate by extraction of gluten with dilute acetic acid, followed by precipitation in alkaline 700 ml litre − 1 ethanol. The absorbance of the turbid mixture was determined by a spectro photometer and may be related to percentage heat damage by comparison with standards. The gluten turbidity test measures loss in baking quality due to heat damage only. Glutenin turbidity was found to be independent of both total protein content and overall gluten quality (as measured by bread loaf volume improvement) for the 23 sound commercial and laboratory samples of gluten tested.
Indicators of maturity in apricots using biplot multivariate analysis
Authors: Brown Gordon S , Walker Timothy D
Published: October 2006

Apricot fruit (Prunus armeniaca L cv ‘Moorpark’) of variable ground colour were harvested from three sites. From two additional sites fruit of one colour only were harvested. Measurements were made of skin ground colour, internal levels of ethylene and carbon dioxide, total soluble solids, flesh firmness, juice viscosity, pH, total titratable acidity and flesh water content. It was found that skin ground colour was a good indicator of physiological maturity in any one site but was a poor indicator between sites. Of the measured parameters only flesh firmness, total titratable acidity and juice viscosity were found to be useful measures of physiological maturity. Due to the preoccupation of marketers and consumers with flesh firmness, it is proposed that this parameter be used each year to determine the optimal picking colour for fruit in individual orchards.
Effect of processing on iron levels in and availability from some nigerian vegetables
Authors: Latunde‐Dada G Oluyemisi
Published: October 2006

The total iron contents of 12 Nigerian local vegetables differed significantly (P<0.05). Whereas blanching resulted in the loss of 14.1–45.4% of total iron, squeeze‐washing resulted in a 15.3–64.4% loss in the total iron. Percentage dialysable iron between these vegetables also differed significantly (P<0.05). Dialysable iron was reduced significantly (P<0.05) after blanching or squeeze‐washing of the vegetables. The addition of kanwa (an alkaline salt) also led to a 13.2–78.6% reduction in the dialysable iron from these vegetables. However, the addition of ascorbic acid enhanced the dialysable iron (P<0.05). This enhancing effect was also observed in the dialysable iron from some blanched vegetables. The results are discussed in relation to their implications for Nigerian feeding habits.
Effect of soaking and boiling treatments on the quality of winged bean seed
Authors: Buckle Ken A , Sambudi Handajani
Published: October 2006

Winged bean (Psophocarpus tetragonolobus (L) DC) seeds were soaked for 24 h in distilled water, 30 or 50 g litre−1 rice husk ash suspension or solutions of 10 or 20 g litre−1 baking soda, or 5 or 10 g litre−1 NaHCO3. Seeds were then boiled for 30 min in these solutions, then either washed and resoaked in distilled water or peeled, washed for 24 h and resoaked for 24 h in distilled water. The pH and level of leached solids increased during boiling. The colour of the bean cotyledon remained light when boiled in distilled water or rice husk ash suspension, but became darker when boiled in the alkaline solutions. Boiling in distilled water or rice husk ash suspensions did not render the bean sufficiently soft, whereas boiling in the alkaline solutions produced adequately soft seeds. There was no significant difference in tenderness of beans given further processing by resoaking or peeling and resoaking compared with boiling. The nature of the cooking liquid had no significant effect on the protein content of the seeds.
Effect of thiolation on the physicochemical and functional properties of bovine serum albumin
Authors: Murphy Margaret C , Howell Nazlin K
Published: October 2006

The effects of the attachment of homocysteine residues, to either 16 or 21 amino groups of bovine serum albumin (BSA), on the physicochemical and functional properties were studied. Both thiolated protein derivatives had a lower isoelectric point, hydrophobicity and α‐helix conformation compared with the native protein. Polyacrylamide gel electrophoresis indicated that modification of the proteins resulted in a mixture of products. Thiolation impaired the whipping and gelling properties of bovine serum albumin but there was little change in the emulsification properties. It was concluded that increasing the available sulphydryl groups did not promote disulphide/ sulphydryl interchange reactions leading to enhanced functional properties: on the contrary, the blocking of amino groups was instrumental in impairing the whipping and gelling properties.
Degradation of starch in feed concentrates by enzymes, rumen fluid and rumen enzymes
Authors: Cone John W
Published: October 2006

The degradation of starch from various feedstuffs was investigated with rumen fluid, α‐amylase, pancreatin and a freeze‐dried, cell‐free preparation of rumen fluid. Rumen fluid was taken from either a hay‐fed cow or a concentrate‐fed cow. It was shown that incubations with rumen fluid at a constant pH of 6·5 gave a higher degradation of starch than those with a decreasing pH. The degree of starch degradation varied widely for the 21 feedstuffs investigated. Sorghum, maize and millet degraded slowly whereas tapioca showed fast degradation. Processed feedstuffs showed a higher level of degradation than unprocessed ones. The use of enzymes did not allow an accurate prediction of starch degradation by rumen fluid. However, this was made possible by the use of a freeze‐dried, cell‐free preparation of rumen fluid. Scanning electron microscopic observations showed that for the degradation of starch granules additional enzymes, present in rumen fluid, are necessary.
Concentrations of trace metals in various tissues of the squid Loligo opalescens and their redistribution after canning
Authors: Falandysz Jerzy
Published: October 2006

The trace metals (Mn, Cu, Zn, Fe, Cd, Pb and Ag) have been determined in various tissues of raw and canned Loligo opalescens squid. As a consequence of processing whole squid, highly elevated levels of cadmium, and to a lesser extent of the other trace metals investigated, were found in the edible parts of canned whole squid.
Aflatoxin contamination in mustard (Brassica juncea) in relation to agronomic practices
Authors: Bilgrami Krishna S , Choudhary Ajoy K , Masood Ahmad
Published: October 2006

Aflatoxin contamination in two varieties of mustard (Brassica juncea L), Varuna and BR‐40, sown on three planting dates (1, 15 and 30 November) under two different cropping patterns, viz monocropping and mixed cropping (along with the UP‐262 variety of wheat), was examined in rabi (winter) crops of 1987–1988 and 1988–1989. Analysis of variance showed a significant effect of planting date and cropping pattern as well as a combined effect of planting date × cropping pattern. Delayed planting (30 November) resulted in a very high level of aflatoxin contamination. The level of aflatoxin was low when mustard was cultivated along with wheat (mixed cropping). Varuna was more susceptible to aflatoxin than BR‐40. The maximum number of fungi was recorded in mixed cropping samples.
Enzymic browning in apricots (Prunus armeniaca)
Authors: Dijkstra Lucette , Walker John R L
Published: October 2006

Enzymic browning in apricots (Prunus armeniaca L) was found to be catalysed by a catechol oxidase (o‐diphenol oxidase) and a laccase (p‐diphenol oxidase), both acting on catechin and chlorogenic acid as the natural substrates. The laccase was identified as such by substrate specificity tests and the effects of selective inhibitors. The enzymes were tightly bound to the fruit tissue and were inactivated by holding at 80°C for 10 min. The levels of phenolic compounds in healthy and rotted apricot tissue were compared by paper chromatography; the levels of catechin and chlorogenic acid were reduced in the rotted tissue.
Acid‐insoluble ash as a marker compound for use in digestibility studies with humans
Authors: Rowan Angela M , Moughan Paul J , Wilson Margaret N
Published: October 2006

The study aimed to evaluate acid‐insoluble ash, in the form of added celite (a diatomaceous earth), as an indigestible marker compound for use in digestibility studies with humans. The study comprised two parts. First, the recovery of dietary acid‐insoluble ash in the faeces was determined in a controlled 10‐day metabolism study involving five 6‐week‐old male pigs receiving food consisting of ingredients commonly eaten by humans. Secondly, the faecal recovery of dietary acid‐insoluble ash was determined with six adult humans following a set diet which maintained their normal levels of daily food intake for 7 days. The mean (±SE) recoveries of dietary acid‐insoluble ash in the faeces of the pigs and human subjects were 90·0 (±2·24) and 92·1 (±4·59)%, respectively. The mean apparent faecal digestibility coefficients for dietary dry matter were not significantly different (P > 0·05) when determined by total faeces collection or by reference to the marker, in both species. It was concluded that celite is a potentially useful dietary marker compound for use in human digestibility studies involving collection of faeces. The marker was readily accepted by the human subjects and can be determined chemically using simple gravimetric analysis.
Acetylenic compounds in stored packaged carrots
Authors: Lund Eric D , Bruemmer Joseph H
Published: October 2006

Stored carrots vacuum packed in plastic shrink bags showed significant variations in the concentration of certain important secondary compounds. In the acetylene group, 18 compounds were isolated and measured. Only eight of these compounds have previously been reported as carrot constituents. The concentrations of 10 of the 18 increased with storage time, and six were present only in stored samples.
Effect of drying conditions on tannin, fibre and lignin levels in mature oak (Quercus incana) leaves
Authors: Makkar Harinder Paul Singh , Singh Bhupinder
Published: October 2006

Oak (Quercus incana Roxb) leaves are rich in tannins and produce adverse effects when fed to livestock. The effects of shade and sun drying and oven drying at 60°C and 90°C for different lengths of time (24 to 72 h) on total phenolics, condensed tannins, protein precipitation capacity, degree of polymerisation, specific activity (protein bound per unit tannins), fibre‐linked proanthocyanidins, acid and neutral detergent fibres and lignin levels in mature oak leaves were studied. Removal/inactivation of tannins was not observed on wilting or drying under several conditions. Similarly the drying conditions had no effect on fibre composition. The adverse effects on feeding fresh or dried oak leaves are expected to be of similar magnitude.
Production of phytase by Aspergillus ficuum and reduction of phytic acid content in canola meal
Authors: Nair V C , Laflamme J , Duvnjak Z
Published: October 2006

Production of the phytase (EC 3.1.3.8) from Aspergillus ficuum in a submerged batch process was inhibited by high concentrations of glucose. The inhibition was overcome by applying a fed batch technique in the production of the enzyme. Tests carried out at different oxygen concentrations revealed that aeration had a beneficial effect on the production of the enzyme. The enzyme showed an optimum pH and temperature of 5·0 and 60°C, respectively. Preincubation of the enzyme preparation at 60°C resulted in relatively fast denaturation of the enzyme. Upon storage at 4°C it lost only 15% of its activity in 5 weeks. Aspergillus ficuum also produced phytase when grown on canola meal by a solid state technique. The enzyme catalysed degradation of the phytic acid present in the meal and completely eliminated it, rendering the commodity more suitable for animal feed. An apparent 10% increase in protein content of the canola meal was noted as a result of the growth of the microorganism.
Multiple molecular forms of finger millet subtilisin and amylase inhibitors
Authors: Vaidyanathan V Viswanathan , Virupaksha Tumkur K
Published: October 2006

Nine varieties of finger millet (Eleusine coracana Gaertn) including a wild form were screened for proteinase and α‐amylase inhibitory activities. Subtilisin inhibitory activity was present in all the varieties examined and was highest in the wild form, while the cultivated varieties had more trypsin inhibitory activity. Isoelectric focusing of a 60% ammonium sulphate fraction of the wild form, before and after complexing with subtilisin, showed multiple forms of subtilisin inhibitors one of which was also active against trypsin. Isoforms of finger millet subtilisin inhibitors were isolated from the ammonium sulphate fraction by ion exchange chromatography on DEAE‐Sephadex followed by SP‐Sephadex chromatography. Copurification of trypsin and α‐amylase inhibitory activities with subtilisin inhibitory activity was observed during cation exchange chromatography. PAGE analysis revealed them to be charge isomers with pI in the range 5·5–6·0. SDS–PAGE gave an estimate of 12 000 mol wt for each of them. Finger millet subtilisin inhibitors were more active on bacterial proteinases than on bovine trypsin and chymotrypsin.
Biosynthesis of limonoid glucosides in lemon (Citrus limon)
Authors: Fong Chi H , Hasegawa Shin , Herman Zareb , Ou Peter
Published: October 2006

TLC analyses of lemon (Citrus limon (L) Burm f) fruit at various stages of maturity showed that limonoid glucosides were synthesised during the late stages of fruit growth. No limonoid glucosides were found in the stem and leaf. Use of radioactive tracers showed that 14C‐nomilin was converted to 14C‐nomilin 17‐β‐D‐glucopyranoside in fruit tissues and seeds. Glucosides are indeed the major end products of limonoid metabolism.
Instron measurement of sponge cake firmness: Effect of additives and storage conditions
Authors: Guinot Patricia , Mathlouthi Mohamed
Published: October 2006

Instron measurement and sensory analysis of sponge cake texture was performed under various conditions. The samples were compared on the basis of their storage in modified atmosphere (CO2/N2, 50:50 v) or not, at + 4°C or + 20°C, as whole cakes or slices of cake, and with or without additives (soya bean protein or sodium alginate). It was found that the best conditions for preservation of a soft texture in a whole cake are obtained in a modified atmosphere at +4°C when 10 g kg−1 soya bean protein is included in the sponge cake formulation.
Physicochemical characterisation of raw fish and stickwater from fish meal production
Authors: del Valle José M , Aguilera José M
Published: October 2006

Chemical and microbiological properties of raw fish (RF) and chemical properties of stickwater (SW) samples were studied as a function of the staleness level of the fish. As time elapsed from fish capture increased, the microbial count in RF, volatile nitrogen content in RF and SW, and dissolved solids and dissolved protein in SW, increased. The apparent viscosity of SW increased as the temperature decreased and as the dry solids or suspended matter content increased. The size distribution of suspended particles in SW depended on the sample preparation technique, method used to measure particle size and whether the size distribution was expressed in terms of the weight or population of fractions. The average size (by weight) of suspended solids in SW was 2.5 μm as estimated by electronic counting. The solubility of protein in SW decreased when acid or alkali were added or thermal treatment (1 h at 90°C) applied. A minimal solubility point occurred near pH 5. The molecular weight of most dissolved proteins in SF was 3 kD. SF also contained a small proportion of 67 kD proteins. The significance of this basic characterisation study for the selection of improved processes for stickwater recovery is discussed.
Quantitative quality tests for frozen fish: Soluble protein and free fatty acid content as quality criteria for hake (Merluccius capensis) stored at −18°C
Authors: de Koning Adrianus J , Mol Theodora H
Published: October 2006

Hake fillets and mince were frozen and stored at −18°C in four different tests. Samples were periodically withdrawn and analysed for total protein, protein soluble in aqueous salt solution, free fatty acid content and texture. Highly significant correlations were found between the texture and both the ratio of protein soluble in aqueous salt solution to total protein and the free fatty acid content. These correlations led to the formulation of quantitative quality criteria based on protein soluble in aqueous salt solution and free fatty acid content for frozen hake stored at −18°C.
Influence of the naturally occurring phosphate esters on the crystallinity of potato starch
Authors: Muhrbeck Per , Eliasson Ann‐Charlotte
Published: October 2006

The gelatinisation enthalpy of native potato starch, as measured by DSC, as observed to decrease ith increased natural phosphorylation of the amylopectin. The phosphate esters bound to the C‐6 carbons clearly reduced the gelatinisation enthalpy, hereas the phosphate esters bound to C‐3 carbons took little or no part in this reduction. Retrograded starch samples ere also studied, in order to find a corresponding relationship beteen the degree of phosphorylation and the recrystallisation enthalpy. These results ere less convincing, but the phosphate esters did tend to increase the retrogradation enthalpy independent of the phosphorylation site.
Cooking quality and nutritional attributes of some nely developed cultivars of chickpea (Cicer arietinum)
Authors: Singh Umaid , Subrahmanyam Nukala , Kumar Jagdish
Published: October 2006

Eight nely developed and to commonly gron chickpea (Cicer arietinum L) cultivars ere evaluated for their cooking quality by measuring cooking time, ater absorption and sensory properties. Nutritional aspects of cooked hole seed samples ere measured chemically (including amino acids and minerals) and biologically in nitrogen‐balance experiments ith rats. Results indicated that kabuli (cream seed coat) may be generally preferred to desi (bron seed coat) cultivars in terms of cooking time and sensory properties. Calcium content as noticeably higher in desi than in kabuli cultivars, hereas magnesium, iron, copper and zinc shoed no definite trend. Levels of lysine, threonine, methionine and cystine of these genotypes ere ithin the range of FAO values. Desi and kabuli revealed no noticeable difference in protein and amino acids. Hoever, biological value as considerably higher for kabuli than for desi. Consequently, kabuli contained more utilisable protein and may be nutritionally better than desi. In general, cooking quality and nutritional aspects of both nely developed and control cultivars ere similar.