bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of force deformation data as indices to hydrocolloid gel strength and perceived texture
Authors: NUSSINOVITCH A. , KOPELMAN I. J. , MIZRAHI S.
Published: July 2010

Yield stress and differential strain have been tested as indices to compare the strength of three different gelling systems with a wide range of mechanical behaviour. Differential strain index was useful because it requires only simple and inexpensive equipment to measure strain on increasing force from 1 to 2 N and it correlates well with yield stress and with several sensory textural attributes. Furthermore, it could be used on gels that do not fracture under normal compression tests, and which cannot be characterized by yield stress. However, in other cases, yield stress is interchangeable with the differential strain index.
Formulation and shelf‐life of a bottled pawpaw juice beverage
Authors: OKOLI E. C. , EZENWEKE L. O.
Published: July 2010

A simple procedure was developed for production of bottled pawpaw beverage juice by peeling and macerating peeled tissue in 25% water, straining through a 0.8‐mm sieve, adjustment of juice pH with citric acid and flavour adjustment with sucrose. Fresh juice was optimized for acceptability at pH 3.9 and 10% (w/w) sucrose. Heating for 6 min at 72.2°C was required to achieve commercial pasteurization. Samples of juice were prepared with no preservative, and containing sodium benzoate (125mg/100ml), sodium metabisulphite (50mg/100ml) and sodium metabisulphite/sodium benzoate combination (25mg and 60mg/100ml) for trials in which acceptability, pH, specific gravity, brix, total acidity, vitamin C and biomass concentrations were measured over 90 weeks storage at 10°C and 30.2°C. Sodium benzoate alone extended the shelf‐life at 30°C up to 80 weeks but the other preservatives were not effective after 20 weeks. The control juice was already deteriorating by 10 weeks at 30°C. At 10°C all preserved samples were stable up to 80 weeks, although the control deteriorated rapidly after 20 weeks.
Review: Enzyme inactivation during heat processing of food‐stuffs
Authors: ADAMS J. B.
Published: July 2010

Enzyme inactivation during heat processing is reviewed with regard to fundamental aspects (structure, thermodynamics and kinetics), mathematical models and the relationship between enzyme activity and food quality. Enzyme stability is related to enzyme structure and to factors in the microenvironment. Kinetics of inactivation are categorized with respect to reaction order and two models are briefly discussed which describe the variation of inactivation rates with temperature. The determination of accurate kinetic parameters is emphasized where the objective is to develop mathematical models of enzyme inactivation in real foods. The value of modelling inactivation is assessed. Enzymes having effects on sensory quality are reviewed with particular emphasis on those enzymes which influence flavour, through lipid degradation, and those which affect texture by catalysing the breakdown of starch, pectin or protein.
Review: Thermal stability of carthamin bound to insoluble polymers – effects of pH and organic and inorganic compounds
Authors: SAITO K. , FUKUSHIMA A.
Published: July 2010

Carthamin was adsorbed onto cellulose, cellulose derivatives, collagen and other polymers and the stability of the bound pigment examined as a function of buffer compositions, pH, the presence of metal ions or organic compounds, temperature and pressure. Free carthamin was labile, especially in aqueous solutions, while bound carthamin remained stable when heated in an oven or retort for 1h at 80‐120°C at 1.0‐2.1 atm. High buffer concentration was necessary for carthamin stability, but at high temperature and high pressure, stability greatly decreased in the presence of water. Metal ions or organic food ingredients had little effect. Basic conditions were also undesirable for preservation of the pigment on insoluble polymers. The results indicate that the bound carthamin has potential as a red‐colouring agent for some processed foods.
Effect of safflower protein isolates on cookie characteristics
Authors: ORDORICA‐FALOMIR C. , PAREDES‐LÓPEZ O.
Published: July 2010

Safflower protein isolates prepared by micellization (MP) and isoelectric precipitation (IP) were incorporated into sugar cookies. A commercial soybean protein isolate was used as reference. The amount of protein isolate added was that needed to increase the protein content of wheat flour by 20, 40 and 60%. Physical and sensory properties of the products were not significantly (P > 0.05) affected by fortification with safflower protein prepared by MP, whereas some deterioration of these properties was observed when IP and soybean isolates were used.
Effect of moisture content on flow behaviour of molten soy‐protein isolate under an elevated temperature
Authors: FUJIO Y. , HAYASHI N. , HAYAKAWA I.
Published: July 2010

The flow behaviour of molten soy‐protein isolate (SPI) with moisture content ranging from 17 to 41% was measured with a capillary rheometer under an elevated temperature of 140°C. The flow‐starting temperature of SPI under 90 MPa pressure was inversely proportional to the moisture content. The relationship between flow rate and pressure drop for a molten SPI with 17‐35% moisture was non‐linear on a log‐log scale, while it was linear for a molten SPI with 41% moisture. Based on these results, the shear characteristic of a molten SPI with 41% moisture can be classified as a power‐law fluid with a flow behaviour index of 0.3. However, a molten SPI with 17‐35% moisture may be classified as an unknown type of non‐Bingham plastic.
Factors influencing the particle size distribution of flaked meat. II. Effect of aperture size, number of cutting stations, rotational speed and impeller design
Authors: SHEARD P. R. , FOSTER‐SMITH A. , JOLLEY P. D.
Published: July 2010

Diced steer flank and brisket were flaked at a nominal temperature of ‐4.0°C to investigate the effects of rotational speed (3360 or 5250 r.p.m.), two different impeller designs, aperture size (1.5, 6.1 and 19.0mm) and number of cutting stations on the resulting particle size distribution, measured using video image analysis. Changes in ice content and enthalpy were also calculated from measurements of temperature before and after flaking.

The amount of ice which melted, and the corresponding enthalpy change, was significantly greater for the smaller aperture sizes, and the higher speeds.

Of the four factors investigated, the most important influence on particle size was that of aperture size. However, under some conditions, the number of cutting stations and the rotational speed also influenced the resulting particle size characteristics, most notably in producing thinner particles.
The effect of natural or artificial casing on the ripening and sensory quality of a mould‐covered dry sausage
Authors: RONCALES P. , AGUILERA M. , BELTRAN J. A. , JAIME I. , PEIRO J. M.
Published: July 2010

Experiments were performed in which the same ingredients were stuffed in either natural pork casing or in an artificial collagen casing. A small‐diameter coarse and mouldy salami, known as ‘fuet’, was tested.

Ripening parameters showed few differences; water content, non‐protein nitrogen, free fatty acids and superficial mould counts were similar, while pH was clearly higher after the fifth day in natural casing, and counts of yeasts were larger in the artificial one. Microscopic observation of cross‐sections has shown a greater colonization of natural casing tissue by moulds. Sensory quality scores for natural casing salami were higher in almost all attributes except for ease of skin peeling. Differences were especially evident in aroma‐related ratings and in overall acceptability. It was concluded that a higher pH due to a deeper and larger colonization of skin tissue by moulds could be responsible for the superior sensory quality of sausages stuffed in natural casing.
Water vapour sorption isotherms of two cake mixes and their components
Authors: LEIRAS M. C. , IGLESIAS H. A.
Published: July 2010

The water vapour sorption isotherms of two cake mixes and of their ingredients were measured to test whether isotherms of mixes could be predicted from those of the ingredients with sufficient accuracy for practical use. Their composition, mainly wheat flour and sugar, accounts for BET type II behaviour up to aw of 0.75, and type III above. Prediction was very poor above 0.75 because of interactions between components, and possibly useful below 0.75, which is the region of greatest interest for defining packaging and storage conditions to maximize shelf‐life of such products.
Measurement of water activity with an electric hygrometer
Authors: STEKELENBURG F. K. , LABOTS H.
Published: July 2010

Specific problems arising from the use of an electric hygrometer for measurement of water activity (aw) are the equilibration period, the calibration of the sensors and the influence of temperature on the values measured in saturated salt solutions and meat products. The instrument proved to be a simple, rapid and reliable means of measuring aw values, provided some precautions are taken.
Short communication: Effect of pre‐soaking on the rate of thermal softening of soybeans
Authors: GANDHI A. P. , BOURNE M. C.
Published: July 2010

Whole soybeans and dehulled soybean cotyledons were soaked in water at ambient temperature for 0, 8 and 12h then cooked in boiling water at atmospheric pressure for up to 6h. In every case there was an initial rapid rate of softening followed by progressively slower softening until, after about 3h, there was little change in firmness. The kinetics of softening of every sample was consistent with the two substrate theory of thermal softening. The firmness ranking in descending order after 15 min cooking was no soak, whole beans > 12h, soak cotyledons > no soak, cotyledons > 8h soak, whole beans > 12h soak, whole beans. This ranking was maintained for the entire cooking period. For whole beans the soaked samples were less firm than the unsoaked samples while for the cotyledons the soaked samples were more firm than the unsoaked. This reversal in behaviour may be caused by the seed coat (skin) retarding the imbibition of water in the whole beans thus delaying the onset of enzyme activity in the bean tissue.
Quality attributes of four rice varieties
Authors: KHAN T. N. , REDDY N. S.
Published: July 2010

The physico‐chemical characteristics, and cooking, eating, milling and nutritive qualities of four varities of rice were measured and wide varietal differences were observed.

There was little variation in gel consistency and gelatinization temperature, but there were marked differences in water absorption, volume expansion and percentage of leach loss.

Eating characteristics of one variety (Ambemohar) were less acceptable than in the other three, and one (MAU‐Sel‐9) had a much higher protein content than the others.

On the whole, the quality of MAU‐Sel‐9 was found to be superior to the other three varieties of rice.
The effect of low‐ or non‐sweet additives on the stability of protein functional properties of frozen cod surimi
Authors: SYCH J. , LACROIX C. , ADAMBOUNOU L. T. , CASTAIGNE F.
Published: July 2010

The cryoprotective effect of low‐ or non‐sweet additives, PalatinitR, PolydextroseR, casein hydrolysate and fish protein hydrolysate (at 8% w/w) as well as lactitol (at 4% and 8% w/w) were compared to an industrial control containing sucrose/sorbitol (8% w/w) and a control without additive in cod surimi stored at –20°C for 4 months. Freeze‐induced protein denaturation was evaluated monthly by salt extractable protein and differential scanning calorimetry analyses of surimi followed by texture and expressible moisture analyses of surimi cooked gels. Results revealed that protein functionality was similarly maintained during frozen storage by lactitol, PalatinitR and PolydextroseR when incorporated in cod surimi at the 8% level. Surimi gels could be produced with textural attributes comparable to 8% w/w sucrose/sorbitol surimi gels, and the level of lactitol in cod surimi could be reduced to 4% w/w without significant alteration of cryoprotection. Some benefits in gel‐forming properties were obtained by adding 8% casein hydrolysate to cod surimi.
Effect of temperature on the particle size distribution of flake‐cut meat
Authors: SHEARD P. R. , JOLLEY P. D. , RUSH P. A. J.
Published: July 2010

Diced forequarter beef was flaked through a 12.9‐mm aperture at 1°C intervals between –2 and – 7°C. Size measurements made using video image analysis showed that temperature had a marked influence on particle size, with lower temperatures resulting in more and thinner particles with a greater surface area than those produced at higher temperatures.

It is argued that changes in particle size with temperature cannot be explained simply on the basis of ice content alone and that other factors, such as the viscosity of the unfrozen fluid, also influence the mechanical properties of the meat.
The response of unripe Conference pears to modified atmosphere retail packaging
Authors: GEESON J. D. , GENGE PIA M. , SMITH S. M. , SHARPLES R. O.
Published: July 2010

Unripe green Conference pears with initial firmness values of 46–55 N were sealed in modified atmosphere (MA) low density polyethylene (LDPE, 30μ) pillow packs and in perforated control packs on three dates during 1985–1986. Changes in pack atmosphere composition, skin chlorophyll content, flesh firmness and sensory quality were monitored during 14–20 days simulated shelf‐life at 20°C. In MA packs, equilibrated atmospheres containing 5–9% CO2 and < 5% O2 developed within c. 3 days. Chlorophyll degradation was completely inhibited by MA and resumed when packs were perforated, but MA only partially retarded the rate of flesh softening. Variations in the rate of ripening changes in duplicate MA packs could not be explained simply by differences in pack atmospheres. Furthermore, pears retarded by MA packaging failed to develop the normal sweet, aromatic flavour and succulent, juicy texture of ‘eating‐ripe’ fruit, even when the packs were perforated after 4 days.

The differences in the responses of pears and apples to MA packaging, and the limitations of using this technique for the commercial marketing of English pears are discussed.
Cause of and methods to reduce methanol content of Tsicoudia, Tsipouro and Ouzo
Authors: KANA K. , KANELLAKI M. , PAPADIMITRIOU A. , KOUTINAS A. A.
Published: July 2010

Methanol of Greek beverages Tsicoudia, Tsipouro and Ouzo was determined. Most grape cultivars gave 700‐1700mgl‐1 methanol in Tsicoudia and Tsipouro. Grapes Liatico, Sultana and Cardinal usually produce less than 1000mgl‐1. Methanol in products obtained by single distillation of wines was lower than 31% of the concentration in products obtained from wines fermented and distilled in the presence of grape skins. Heat treatment of must also further reduced methanol when heat was applied to must in the absence of grape skins. Double distillation and rejection of the first part of distillate did not result in any reduction of methanol.
A clouding agent based on modified soy protein
Authors: GARTI N. , ASERIN A. , AZARIA D.
Published: July 2010

Several food proteins, together with some naturally occurring water‐soluble gums (viscosity builders) and lecithin, are evaluated as clouding agents for formulated orange drinks. The use of these three types of natural products represents a significant advantage over the present formulations in which synthetic emulsifiers and weighting agents are used.

The effects of concentration of each of the above ingredients, pH, temperature and mode of preparation are explored and related to cloud stability, droplet size distribution and the opacity of the emulsion both in concentrated and diluted formulations. A mechanism for protein adsorption onto the droplets is suggested.
Thermal stability of fish myofibrils: a differential scanning calorimetric study
Authors: HOWELL B. K. , MATTHEWS A. D. , DONNELLY A. P.
Published: July 2010

The variation in myofibrillar protein thermostability was compared for various fish species, using differential scanning calorimetry. The tropical fish, catfish (Clarius gariepinus), carp (Cyprinus carpio), Nile perch (Lates niloticus), red snapper (Lutianus sebae), red mullet (Parpeneus barberinus), sea bream (Gymnocranius rivalatus), and cold‐water reared trout (Salmo gairdneri) and cod (Gadus morhua) were analysed. Onset temperature of myofibrillar protein denaturation occurred at up to 11°C higher for tropical species (43.5°C, catfish), than cod (32.6°C) at pH 7 and low ionic strength (I). As pH (6.0‐8.0) and I (0.05‐1.00) were increased, thermal denaturation temperatures of myosins from tropical, but not cold‐water, species decreased. Enthalpies of myofibrillar denaturation decreased for all species with increasing pH and I. Only one thermal transition was detected for myosin at pH 6 and low I, increasing to three as pH and I were increased. Changes in thermal characteristics of myosin subunits over iced and frozen storage suggest more rapid deterioration in cold‐water than in tropical fish. The differences in myofibrillar stability of fish from different habitat temperatures have implications for the processing and storage of tropical fish.
INT reduction as a basis for determining bakers' yeast viability
Authors: BITTON G. , IVANOFF D. B. , KOOPMAN B.
Published: July 2010

Two rapid and simple methods for determining the reduction of 2‐(p‐iodophenyl)‐3‐(p‐nitrophenyl)‐5‐phenyltetrazolium chloride (INT) to INT‐formazan by bakers' yeast were compared. The first method involves counting with a light microscope the number of yeast cells containing INT‐formazan crystals. In the second method, INT‐formazan is extracted from cells retained on membrane filters, using dimethyl sulphoxide. The INT‐formazan is then quantitated by absorption spectrophotometry. Several brands of bakers' yeast of various ages were tested. Results obtained with the two methods were closely correlated. The extraction method is the more rapid and convenient of the two assays investigated and may be used to follow change in activity with time, compare various yeast brands or investigate the effect of various environmental conditions on yeast INT‐dehydrogenase activity.
The composition of the fatty acids and aldehydes of the ethanolamine and choline phospholipids of various meats
Authors: FOGERTY A. C. , WHITFIELD F. B. , SVORONOS D. , FORD G. L.
Published: July 2010

The ethanolamine phospholipids of beef, lamb, pork and chicken examined in this study contained over 40% of ethanolamine plasmalogen, whereas fish contained only 13%. The level of choline plasmalogen in choline phospholipids was less than 1% in fish and ranged from 10 to 30% in the other four meats. Palmitaldehyde was the major fatty aldehyde in the choline plasmalogens of beef, lamb, pork and chicken (65–80% of total aldehydes), but was present at lower levels in the ethanolamine plasmalogens. The per cent fatty acid compositions of phosphatidylethanolamine and the corresponding ethanolamine plasmalogen were very similar, being typically low in palmitic acid but very high (56–74%) in polyunsaturated fatty acids. The fatty acids of the choline plasmalogens contained more polyunsaturated fatty acids than the corresponding phosphatidyl cholines, but at lower levels than in the fatty acids of the ethanolamine phospholipids.
Fluorimetry via a quartz‐glass rod for predicting the skin content and processing characteristics of poultry meat slurry
Authors: SWATLAND H. J. , BARBUT S.
Published: July 2010

Collagen fluorescence in comminuted mixtures of chicken skin and muscle was measured through a quartz‐glass rod. High proportions of skin decreased the gel strength of the cooked product (r=—0.99, P < 0.005), caused higher cooking losses (r = 0.99, P < 0.005) and decreased the fluid‐holding capacity measured by centri‐fugation (r=—0.92, P < 0.005). Fluorescence intensity was strongly correlated with skin content (r<0.99 from 460 to 510 nm) and, thus, was strongly correlated with gel strength, cooking losses and fluid‐holding capacity.
Effect of amidation on the foaming and physico‐chemical properties of bovine serum albumin
Authors: HOWELL NAZLIN K. , TAYLOR CLAIRE
Published: July 2010

Amidation of bovine serum albumin (BSA) was achieved by a water‐soluble carbo‐diimide, ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide (EDC)‐mediated reaction using ammonium chloride as the nucleophile. Partial and substantial amidation of 0.5% (w/v) BSA in 5.5 m ammonium chloride solution with 1 times 10‐2mmol EDC over 120 min and 1 times 10‐1mmol EDC over 10 min respectively was achieved on a large scale using diafiltration for rapid termination of the reaction and purification. Residual ammonium chloride otherwise enhanced foaming properties. The amidated proteins were characterized by isoelectric focusing, electrophoresis and hydrophobicity and disulphide‐ and sulphydryl‐group measurements. Compared with native BSA, partially amidated BSA (PA‐BSA) produced enhanced foam expansion and foam stability values. This was attributed to minimal denaturation and to the presence of both acidic and basic components (pI range 5.25–7.50) within the single protein. In contrast, substantially amidated BSA (SA‐BSA) (pI range 7–9.1) had similar foaming properties to those of the ultrafiltered BSA control which were slightly lower than those of native BSA. However SA‐BSA interacted synergistically with native BSA producing enhanced foaming properties particularly at the 1:1 ratio through electrostatic interactions, conformational changes and increased hydrophobicity.
Influence of γ‐irradiation and ice storage on fat oxidation in three Indian fish
Authors: GHADI S. V. , VENUGOPAL V.
Published: July 2010

The influence of low‐dose γ‐irradiation (up to 5 kGy) on fat oxidation in skin and flesh fractions of some commercially important fishes (Indian mackerel, white pomfret and seer) during ice storage was examined. Thiobarbituric acid (TBA) values increased in both control and irradiated fish particularly in mackerel and seer meat. In mackerel, the TBA values declined towards later part of storage. Pomfret skin, but not mackerel and seer skin, showed radiation‐induced oxidation, which increased further during ice storage.
Optimization of extrusion cooking of lung proteins by response surface methodology
Authors: BASTOS D. H. M. , DOMENECH C. H. , ARĚAS J. A. G.
Published: July 2010

Conditions for extrusion cooking of dried ethanol defatted bovine lung were optimized using response surface methodology (RSM) with the method of steepest ascent to maximize expansion ratio in terms of temperature of the central zone of the extruder and moisture content of the feed. Water absorption capacity showed no significant variation over the range studied, but the emulsifying capacity showed a significant increase with decreasing moisture content of the feed. The extruded product could improve utilization of an otherwise waste product.
Vitamin profiles of kefirs made from milks of different species
Authors: KNEIFEL W. , MAYER H. K.
Published: July 2010

Kefirs were produced under laboratory conditions using 10 different kefir grain cultures from different households, and reconstituted cow, ewe, goat and mare milk as substrates. The base milks and corresponding kefirs were examined for their content of water‐soluble vitamins and orotic acid. On average, enrichment of vitamin concentration of>20% was observed with thiamine (only ewe milk kefirs), pyridoxine (kefirs from all milk species except cow milk), and folic acid (kefirs from all milk species except mare milk). Orotic acid content was reduced during fermentation throughout.
The use of the Multiple Comparison Test in checking product variability
Authors: GRIFFITHS NERYS M.
Published: July 2010

The Multiple Comparison Procedure, in which the size of difference of a number of samples from a labelled control is assessed by a panel, was used to demonstrate the flavour variation between jars of two commercial brands of instant coffee. One brand was shown to have moderate to large flavour differences between jars, whereas in the other brand, differences were generally slight. The procedure is suitable as a quality control technique for comparing a number of samples at a panel session.
Stabilization of ascorbic acid by microencapsulation in liposomes
Authors: KIRBY C. J. , WHITTLE C. J. , RIGBY N. , COXON D. T. , LAW B. A.
Published: July 2010

Ascorbic acid was encapsulated with high efficiency inside liposomes. In this form, its stability was enhanced compared to that in free aqueous solution, and particularly in the presence of a number of factors widespread in foods, which normally lead to its rapid degradation. Possible mechanisms for these stabilizing effects are discussed. Amongst other potential applications, these findings are relevant to the preservation of nutritional supplements of vitamin C in solution and to the development of naturally derived antioxidant systems for food protection.
Chemical interesterification of olive oil‐tristearin blends for margarines
Authors: GAVRIILIDOU V. , BOSKOU D.
Published: July 2010

Refined olive oil–glycerol tristearate blends were interesterified using sodium methoxide as catalyst. The glyceride structure of the randomized fats was studied and the relationship between the structure and physical properties was examined. The rearranged fats were investigated for Solid Fat Index, melting behaviour, consistency and spreadability and the values obtained were compared to those of zero‐trans margarines or commercially available products prepared from hydrogenated olive oil and other vegetable oils. The 80:20 and 75:25 olive oil–tristearin blends after randomization have properties very close to those of soft tub and packet margarines.
Indirect ELISA for detection of goats' milk in ewes' milk and cheese
Authors: RODRÍGUEZ E. , MARTÍN R. , GARCÍA T. , AZCONA J. I. , SANZ B. , HERNÁNDEZ P. E.
Published: July 2010

An indirect ELISA (enzyme‐linked immunosorbent assay) has been developed successfully for the detection of defined amounts of goats' milk (1–25%) in ewes' milk and cheese. The assay uses polyclonal antibodies raised in rabbits against goats' caseins (GC). The anti‐GC antibodies were recovered from the crude antiserum by immunoadsorption and elution from a column containing immobilized goats' caseins. The anti‐GC antibodies were biotinylated and rendered goats' milk specific by mixing them with lyophilized bovine and ovine caseins. The assay was developed in a non‐competitive ELISA format and it comprised coating plates with extracts from samples. ExtrAvidin‐peroxidase was used to detect the biotinylated anti‐GC antibodies bound to goats' caseins immobilized on 96‐well plates. The colour developed by the subsequent enzymic conversion of the substrate resulted in discernible differences in optical densities when assaying mixtures of ewes' milk and cheese containing variable amounts of goats' milk.
Effect of pasteurization and fermentation on residues of sulphonamides in sausages
Authors: ELLERBROEK L. I. , STEFFEN G.
Published: July 2010

The different effects of pasteurization and fermentation on sulphamethazine (SMZ) and sulphachlorpyridazine (SCP) were investigated in two common German meat products, luncheon meat and raw fermented sausages. There was no decrease in sulphonamide concentration (5 μg g‐1) in luncheon meat during the different stages of processing and storage (4°C up to 27 days). Less than 40% of the initial concentration remained in fermented sausages after ripening for 10 days in a climatized room. The sulphonamide content was reduced only if fermentation was involved in contrast with meat contaminated with other chemotherapeutic residues.
Effect of shooting period, region of growth and processing method on the Fe and Mn content of tea determined by X‐ray fluorescence
Authors: SAHIN Y. , NAS S. , GÖKALP H. Y.
Published: July 2010

X‐ray fluorescence (XRF) is an effective technique for qualitative and quantitative analysis of minerals in various agricultural products. Simplicity, high throughput and the possibility of automation make it useful for screening large numbers of samples. Samples of 138 fresh green, black tea and residue of this black tea after brewing were obtained from the Eastern Black Sea region of Turkey and analysed for Fe and Mn content using XRF. Such work appears not to have been reported so far.
Bioavailability to rats of iron from fortified grain amaranth flour
Authors: OLOGUNDE M. O. , SHEPARD R. L. , AFOLABI O. A. , OKE O. L.
Published: July 2010

In this study, fortified and unfortified grain amaranth seed flour and FeSO4 fortified casein diet as control were evaluated for their iron bioavailability. NaFeEDTA, ferrous fumarate, and FeSO4‐fortified grain amaranth were fed to Sprague Dawley weanling male rats. Iron intake, Hb Fe gain, Fe availability and binding capacity, serum iron, non‐haem liver iron and relative biological value (RBV) were determined and values compared with FeSO4‐fortified casein control; all were improved greatly by fortification.

Relative biological values (RBV) were 0.40, 1.55, 1.75, 1.67 and 1.00 for animals receiving unfortified amaranth diet, those fed diet fortified with NaFeEDTA, ferrous fumarate, FeSO4 and casein fortified with FeSO4 respectively. RBV of the unfortified cereal was 40% of control suggesting perhaps low iron absorption from the amaranth cereal.

Based on the results of this study, amaranth cereal is ideal as a food vehicle for iron fortification. The iron fortificant of choice is ferrous fumarate.
Effect of irradiation and modified atmosphere packaging on the microbiological and sensory quality of pork stored at refrigeration temperatures
Authors: GRANT IRENE R. , PATTERSON MARGARET F.
Published: July 2010

The effect of combining low‐dose irradiation (1.75 kGy) with modified atmosphere packaging (MAP) on the microbiological and sensory quality of pork chops stored at refrigeration temperatures was studied. The microflora of irradiated MAP pork was almost exclusively composed of lactic acid bacteria, predominantly Lactobacillus spp. Modified atmospheres containing either 25 or 50% CO2, balance N2, resulted in the best microbial control in irradiated pork held at 4°C, compared to an unirradiated MAP control, and these atmospheres were subsequently used in sensory studies. The atmosphere containing 25% CO2 75% N2 maintained the uncooked colour and odour of irradiated pork chops more effectively than 50% CO2 50% N2. Therefore packaging in a modified atmosphere containing 25% CO2, balance N2, followed by irradiation to a dose of 1.75 kGy is recommended to improve the microbiological and sensory quality of pork chops.
Effect of irradiation and modified atmosphere packaging on the microbiological safety of minced pork stored under temperature abuse conditions
Authors: GRANT IRENE R. , PATTERSON MARGARET F.
Published: July 2010

The safety of irradiated pork packed in 25% CO2:75% N2 and stored at abuse temperature (10 or 15°C) was assessed by inoculation studies involving Salmonella typhimurium, Listeria monocytogenes, Escherichia coli, Yersinia enterocolitica and Clostridium perfringens. Irradiation to a dose of 1.75 kGy reduced pathogen numbers to below the detection limit of 102 cells g‐1. When higher inoculum levels were used (106 cells g‐1) irradiation at 1.75 kGy reduced pathogen numbers by 1 –>5 log10 cycles depending on strain. Clostridium perfringens was the most resistant, and Y. enterocolitica the most sensitive of the pathogens studied.

In all cases when high numbers (106 to 107g‐1) of spoilage and/or pathogenic bacteria were present initially on the pork the meat appeared spoiled, and although irradiation reduced the number of microorganisms, the meat was still unacceptable from a sensory viewpoint after treatment.

It was concluded that the microbiological safety of irradiated, modified atmosphere packaged (MAP) pork is better than that of unirradiated MAP pork.
Moisture isotherms of cornchips at three temperatures
Authors: ACHOBA I. I. , ELEGBEDE J. A. , AGBAJI A. S. , AGBAJI E. B.
Published: July 2010

The moisture sorption isotherms of cornchips at three ambient temperatures (27, 35 and 40°C) were sigmoidal, a function of temperature and described by the Henderson equation. Storage stability of the product would be enhanced below 27°C and 3.4 moisture content dry basis (d.b.). The isosteric heats of sorption were calculated.
Amorphous state and delayed ice formation in sucrose solutions
Authors: ROOS Y. , KAREL M.
Published: July 2010

Phase transitions of amorphous sucrose and sucrose solutions (20–100% sucrose) were studied using differential scanning calorimetry, and related to viscosity and delayed ice formation. Glass transition temperature (Tg) was decreased by increasing water content. Ice formation and concurrent freeze concentration of the unfrozen solution increased apparent Tg. Tg could be predicted weight fractions and Tg values of components. Williams–Landel‐Ferry (WLF) relation could be used to characterize temperature dependence of viscosity above Tg. Crystallization of water above Tg was time dependent, and annealing of solutions with less than 80% sucrose at –35°C led to a maximally freeze‐concentrated state with onset of glass transition at –46°C, and onset of ice melting at ‐34°C. The state diagram established with experimental and predicted Tg values is useful for characterization of thermal phenomena and physical state at various water contents.
Entrance effect correction on the flow of moisturized soy protein isolate melt in an extrusion viscometer
Authors: HAYASHI N. , HAYAKAWA I. , FUJIO Y.
Published: July 2010

A newly developed capillary viscometer, having an airtight sample cell and capillary system, was utilized to determine the flow properties of moisturized [70% dry basis (d.b.)] soy protein isolate (SPI) melt at 140°C. Pressure drop measurement with an orifice die was done to clarify the large end effect. An end effect correction method was performed by subtracting the orifice die data from the capillary tube data, and reasonable results were obtained. The flow properties of the SPI melt were thus elucidated and could be classified as those of a power law fluid with flow behaviour index of 0.35. It was concluded that SPI with 70% d.b. moisture is an extremely high pseudoplastic fluid at 140°C.
Changes in the concentration of organic acids during the soaking of soybeans for tempe production
Authors: MULYOWIDARSO R. K. , FLEET G. H. , BUCKLE K. A.
Published: July 2010

Soybeans were soaked for 24h in tap water at 30°C in preparation for tempe fermentation. Soaking was conducted under conditions that give a microbial fermentation, and in the presence of antibiotics where microbial growth was inhibited. Valeric, propionic, formic and acetic were the main acids in the beans. Their concentrations decreased progressively during soaking as they were leached from the bean into the soak‐water. At the end of soaking, lactic and malic were the main acids in the beans. They were produced by microbial fermentation in the soak‐water and diffused into the beans. The concentration of acids produced in the soak‐water was determined by the microbial species responsible for the fermentation.
Changes in lipids and in sensory attributes on storage of rice milled to different degrees
Authors: PIGGOTT J. R. , MORRISON W. R. , CLYNE J.
Published: July 2010

Under‐milled and well‐milled rice samples were compared, before and after storage, by chemical and sensory tests. Surface lipids, non‐starch lipids, and starch lipids were quantified, and free fatty acids, total carbonyls and hexanal contents of the surface lipids were determined as measures of lipid hydrolysis and oxidation during storage for up to 9 months at ‐20 and 30°C. Descriptive sensory analysis of cooked rice by a trained panel was used to compare odour, taste and mouth‐feel of both stored and freshly milled samples. Triangle and preference tests by an untrained panel were used to establish whether perceptible differences were caused by the degree of milling or the storage conditions. Similar changes, both chemical and sensory, occurred in the under‐milled and well‐milled rice during storage but these were more pronounced in the under‐milled rice, leading to a product of poorer storage stability and reduced preference.
Effect of packaging and frozen storage temperature on beef pigments
Authors: LANARI M. C. , ZARITZKY N. E.
Published: July 2010

The influence of final freezing and storage temperature on pigment modifications of beef samples wrapped in polyethylene and EVA/SARAN/EVA was analysed. Met‐, oxy‐ and myoglobin relative surface concentrations were determined using reflectance spectrophotometry. Pigment behaviour during storage of beef packaged in both films and oxygenation of vacuum‐packaged samples was described by different reaction schemes and modelled to obtain kinetic and equilibrium constants. Comparative studies performed with beef samples (a) refrigerated, (b) frozen to –5°C and stored at this temperature (partial freezing), and (c) frozen to ‐25°C and stored at ‐5 and ‐20°C, indicated that for aerobic storage periods of 90 days, metmyoglobin levels of partially frozen samples upon thawing were comparable to those of frozen samples stored at –20°C. For vacuum‐packaged beef, pigment concentrations remained practically constant during frozen storage; partial freezing increased oxygenation capacity of the tissue compared with chilled and frozen conditions.
Effect of Co2 or vacuum packaging on normal and high pH meat shelf‐life
Authors: Rousset S. , Renerre M.
Published: July 2010

In order to extend meat shelf‐life, normal‐pH and high‐pH beef steaks were packaged under vacuum or in 100% C 0 2 atmosphere. Microbiological, colour (L*, a*, b*)

and reflectance (R630‐R580 values) characteristics were measured.

After packaging under vacuum, Enterobacteriaceae, Brochothrix thermosphacta and Pseudomonas numbers were 10‐ to 100‐fold greater on high‐pH meat than on

normal‐pH meat.

Packaging under C 0 2 improved the shelf‐life of meat, particularly that of high‐pH meat up to 42 days. For both high‐ and normal‐pH meats, the bacterial flora was

composed only of lactic acid bacteria. Normal‐pH meat in C 0 2 atmosphere and vacuum packaging had a purple colour. After C02‐pack opening the meat colour

became bright red and R630‐ R580 measurements were high, whereas after opening of vacuum packaging R630‐R580 decreased rapidly with increasing aerobic exposure.

High‐pH meat became paler with increasing storage time in C02. Simultaneously R630‐R580 values increased and the pH fell. In addition it lost less exudate and

oxidized less in air than the normal‐pH meat under the same conditions.
Evaluation of a pilot on‐line instrument for the measurement of lean content of cartoned boneless beef
Authors: DAVEY K. R. , LOVETT D. A.
Published: July 2010

A laboratory evaluation of a pilot, new instrument for the on‐line (batch continuous) measurement of the per cent chemical lean content (CL) of whole cartons (nominally 27.2 kg) of boneless beef, based on an idealized design, is reported. For 24 cartons obtained from an export meatworks there was a highly linear (P < 0.001) dependence of CL on (reciprocal of) the instrument reading. The standard deviation of the predicted CL about this regression line was 2.02. For a further 20 cartons in which the cardboard was equilibrated at high RH prior to packing with the meat, the standard deviation in CL was 3.14. Predictions for CL were not significantly influenced by the order in which the meat pieces were packed into the carton, but were significantly (P< 0.001) affected by the size of the meat pieces. Best results of predicted CL were obtained with large meat pieces in cartons as supplied from the meatworks. These findings together with the fact that model predictions were not improved by a temperature term for meat (range 8.7–15.7°C) should augur well for future development of the instrument.
Validation of a time‐temperature‐integrator for thermal processing of foods under pasteurization conditions
Authors: HENDRICKX M. , WENG Z. , MAESMANS G. , TOBBACK P.
Published: July 2010

In this work, a general theory for the development of a Time Temperature Integrator, TTI‐system, is outlined. A z‐value (or activation energy) of the TTI‐system equal to that of target index is crucial for the usefulness of a system to monitor the impact of thermal processes on foods. The proposed TTI, namely the heat‐stable fraction of peroxidase covalently immobilized on porous glass beads in dodecane, can be used to indicate the intensity of a delivered pasteurization process when a z‐value of 10°C is used for calculating the lethality. Lethalities read from the bio‐indicator showed excellent agreement with those integrated from the measured time‐temperature data.
The influence of water activity on thermal stability of horseradish peroxidase
Authors: HENDRICKX M. , SARAIVA J. , LYSSENS J. , OLIVEIRA J. , TOBBACK P.
Published: July 2010

The thermal stability of horseradish peroxidase in the solid state was studied as a function of water activity, from 0.11 to 0.88. At all activities the enzyme was found to be much more stable in the solid state than in solution. Inactivation temperatures were in the range of 140–160°C. Inactivation curves show a biphasic behaviour which can be described by a model assuming two fractions (heat labile and heat stable) with independent first order inactivation kinetics. The labile fraction represents approximately 30% of the total activity. The z‐value for both stable and labile fractions depends on water activity (moisture content) and has a maximum at aw= 0.76 (44.4°C and 43.8°C, respectively).
Physical texture as an indicator of processing conditions for canning low‐acid artichoke hearts
Authors: RODRIGO MIGUEL , GARCÍA MANUEL G. , RAMIREZ LOLA , MARTÍNEZ ANTONIO , GINER VICENTE , SAFÓN JOSÉ
Published: July 2010

Kramer shear cell measures of texture of artichoke hearts were used to establish thermal loss parameters. A D121= 25.5 min. and a z = 27°C for texture were obtained, with a high correlation between texture and treatment time. Maximum conservation of texture, in canned low‐acid artichoke hearts in 0.5 kg cans (71.5 × 117 mm) whilst still ensuring microbiological stability, was obtained by heating at 121°C for 15 min.
Effect of water hardness on cooking characteristics of cowpea (Vigna unguiculata L. Walp) seeds
Authors: UZOGARA STELLA G. , MORTON IAN D. , DANIEL J. W.
Published: July 2010

Cowpeas were cooked in water made hard (or soft) by the separate addition of similar concentrations of certain salts (CaCl2, MgCl2, or NaHCO3). The beans were also cooked in hard tap water and in double distilled water before and after soaking in water. Hard water caused a significant decrease in softness, led to reduced water absorption, and also decreased solids loss in the cooked product, but it increased the cooking time and discolouration of the beans. Hard water also gave rise to a significant (P<0.05) increase in mineral content, but it had less effect on the proximate composition of the cooked products.
Effect of temperature on chlorophyllase activity, chlorophyll degradation and carotenoids of Cavendish bananas during ripening
Authors: THOMAS P. , JANAVE M. T.
Published: July 2010

Changes in chlorophyllase activity, chlorophyll and carotenoid content of Giant Cavendish banana fruit peel during ripening were measured at tropical temperatures (30–34°C) and at 20°C to relate them to the greenish and yellow colours of the fruit ripened at these temperatures. At 30–34°C bananas remained green on ripening due to incomplete chlorophyll degradation while at 20°C complete degreening occurred and fruits turned yellow. Peel total carotenoid content remained constant during ripening and did not change with temperature. Free xanthophylls decreased while xanthophyll esters increased on ripening. Chlorophyllase activity increased during ripening and paralleled the respiratory climacteric, although activity was not consistently related to the differential degradation of chlorophyll at these temperatures. Exogenous application of ethylene and ethrel accelerated ripening, but had no effect on chlorophyllase levels, chlorophyll degradation and carotenoid content of bananas ripened at either 30–34°C or at 20°C.
Effect of maturity and processing on bitter compounds in Thai tangerine juice
Authors: NOOMHORM ATHAPOL , KASEMSUKSAKUL NITTAYA
Published: July 2010

Optimum conditions of fruit maturity and processing for improved quality of Thai tangerine fruit juice were evaluated. Limonin and naringin components causing bitterness, acidity, total soluble solids and vitamin C were quantified in specified fruit setting and processing conditions.

Higher limonin contents were observed in tangerine fruits harvested early in the season of 1989, whereas naringin contents gradually decreased with maturity. The optimum harvesting time for Thai tangerine fruit which meets the worldwide quality indicators of extracted juice was nine months after fruit set.

Low temperature storage of tangerine juice was only effective in delaying limonin formation if not pasteurized, which resulted in higher limonin concentrations at the start of the storage period. However, naringin concentrations of tangerine juice were not affected by storage conditions and the pasteurization process. Lower extraction pressure of juice resulted in low limonin and naringin concentrations.
Esterification of polyunsaturated fatty acids with lipases from different sources
Authors: LIE E. , MOLIN G.
Published: July 2010

Enzymatically catalyzed esterification between glycerol and polyunsaturated fatty acids were studied for six lipases of different biological origin. Most efficient was lipase from Mucor miehei (yeast) and Chromobacterium viscosum (bacterium) which incorporated free fatty acids in the glycerol to 75% and 80%, respectively. Both lipases showed a slight preference for oleic acid. M. miehei lipase incorporated eicosapentaenoic acid at the same level as the acid occurred in the free fatty acid fraction while C. viscosum lipase incorporated the acid at a lesser level. Both lipases esterified less docosahexaenoic acid.
A new hydroxy fatty acid from Scindapsus officinalis seed oil
Authors: DAULATABAD CHIRAG D. , MIRAJKAR ABDURAZZAQUE M.
Published: July 2010

A new hydroxy fatty acid characterized as 11‐hydroxy‐cis, cis,5,8‐tetracosadienoic acid together with cyclopropenoid fatty acids have been isolated from seed oil of Scindapsus officinalis. The identification was based on IR, NMR, MS and chemical degradations.
Growth of Staphylococcus aureus in fermenting tempeh made from various beans and its inhibition by Lactobacillus plantarum.
Authors: ASHENAFI M. , BUSSE M.
Published: July 2010

In fermenting tempeh made from non‐acid‐soaked horsebean, pea, and soybean Staphylococcus aureus grew rapidly to a final count of 108cfu.g‐1 or more, but growth was less when chickpea was used. Inoculation of the cooked beans with Lactobacillus plantarum markedly decreased S. aureus growth rate and the final count in non‐acid‐soaked horsebean and pea tempeh, strongly retarded growth in chickpea‐, and completely inhibited growth in soybean‐tempeh. Acid‐soaking the beans resulted in lower S. aureus growth, and inoculation with Lb. plantarum completely inhibited it in soybean and reduced the counts in the other products to less than 104cfu.g‐1. Acidity, pH and other substances produced by Lb. plantarum are believed to inhibit S. aureus in fermenting tempeh. Inoculation of beans with Lb. plantarum may be used to control S. aureus growth and enterotoxin production during commercial scale tempeh production.