bluuebunny/crossref_metadata_2025 huggingface dataset:
Baking performance of hen's egg yolk plasma before and after induced aggregation
Authors: KAMAT V. B. , PARTRICK B. , YOELL R. , STUBBS J. M.
Published: July 2010

Yolk plasma has been examined before and after (a) freeze‐thaw gelation and (b) heat‐setting at 62·5°C for aggregation states by gel filtration and electron microscopy and for its performance in standard Madeira cake baking. Frozen and thawed plasma consists predominantly of large aggregated species of lipoprotein particles. Heat set plasma has a lower degree of aggregation than frozen and thawed samples. It is richer in aggregated species than untreated plasma. The aggregation state is not readily reversed by egg white and/or sucrose The degree of aggregation does not appear to affect the baking performance of plasma. Implications of this finding are discussed in terms of possible relationship of lipoprotein size distribution to baking function.
Quality of home frozen vegetables
Authors: HUDSON MARGARET A. , SHARPLES VALERIE J. , PICKFORD ELIZABETH , LEACH MARGARET
Published: July 2010

Home frozen vegetables are normally blanched in water and cooled in iced water before freezing. In this survey, the effects of common household additives to blanching and/or cooling water were studied. Runner beans, peas, perpetual spinach and brussels sprouts were assessed by a tasting panel after being blanched and/or cooled in one of the following solutions, 1·2% NaCl, 2·0% NaCl, 1·2% sucrose, 0·25% sodium carbonate or 0·25% sodium bicarbonate, and stored at – 18°C. The appearance of sprouts was slightly improved by 1·2% NaCl and 1·2% sucrose blanching liquids. Flavour of runner beans was significantly increased by the use of 1·2% salt, but the 2% levels significantly lowered scores for appearance and texture. Sugar significantly lowered texture scores for beans, but improved those for peas. Quality of spinach was not significantly affected by any treatment. Carbonate and bicarbonate treatments tended to have an adverse effect on texture and appearance.

Vitamin C analyses for thawed frozen sprouts blanched in 1·2% NaCl or 1·2% sucrose showed that the treatments did not lower the ascorbic acid content.
The ultrastructure and tenderness of highly cold‐shortened muscle
Authors: MARSH B. B. , LEET N. G. , DICKSON M. R.
Published: July 2010

In an attempt to explain the paradoxical tenderizing, observed when muscle shortening exceeds about 40% of the initial excised length, the fine structure of highly cold‐shortened muscle has been studied by light and electron microscopy. Tissue at the ‘peak’ of toughness is uniformly shortened and shows no sign of structural weakness or damage, but with further shortening super‐contraction and node formation take place in an increasing proportion of the sarcomeres. Widespread fibre fracturing is seen in the internodal zones when the length change has exceeded about 50%. This disruption appears sufficient to account for the declining toughness which accompanies supra‐physiological shortening.
Measurement of the heat production in beef muscle during rigor mortis
Authors: MORLEY M. J.
Published: July 2010

The post mortem heat production in beef at body temperature has been measured by observing the rise in temperature of the muscles M. semitendinosus and M. extensor carpi radialis when enclosed in an insulated container submerged in a water bath at 37°C. The variation with time of the muscle's radial temperature profile was measured using a multi‐junction thermocouple probe and a data logger, and this enabled the heat loss to be calculated. The mean values obtained for the total heat production during rigor mortis were 6·4 kJ/kg for M. semitendinosus and 7·9 kJ/kg for M. extensor carpi radialis, these being equivalent to temperature rises of 1·8°C and 2·2°C respectively, in perfectly insulated muscles. The heat production per unit decrease in pH averaged 5·4 kJ/kg for M. semitendinosus and 6·8 kJ/kg for M. extensor carpi radialis. The rate of heat production reached a mean maximum level of 1·5 kj/kg hr, which was maintained until 4–5 hr post mortem before decreasing to zero. These results are in general conformity with calculations based on the known relations of glycogen, phosphocreatine and ATP.
Chilling of poultry: the effects of process parameters on the level of bacteria in spin‐chiller waters
Authors: BLOOD RUTH M. , JARVIS B.
Published: July 2010

A survey has been made of the effects of process parameters on the microbiological contamination of spin‐chiller waters at five poultry process plants in the UK. Water samples, taken at hourly intervals, from both the first and second chillers were examined bacteriologically and for the levels of residual chlorine pH value and turbidity. Water usage was also monitored. In one process line comparison was made of the effect of substantial modification to the process plant resulting in changes in both water usage and chlorination levels.

The colony counts of presumptive coliform bacteria and other bacteria were reduced generally to < 11 and < 32 ml–1 respectively when high water usage (> 41/kg carcass weight) was combined with high total residual chlorine (30–50 ppm). Higher numbers of bacteria (normally < 105 ml–1) were recovered when high water usage (> 41/kg) was combined with low residual total chlorine (< 5 ppm) or when low water usage (< 1 1/kg) was combined with moderate levels of residual chlorine (7–16 ppm). The signifiance of the results is discussed with reference to the hygienic operation of spin‐chillers.
Utilization of edible protein from meat industry by‐products and waste
Authors: YOUNG R. H. , LAWRIE R. A.
Published: July 2010

Spun proteins which may be acceptable as meat analogues have been fabricated from blood plasma. It was found that plasma protein, initially concentrated by partial freeze drying, could be converted into a suitable form for spinning by denaturation with alkali followed by the addition of a weak acid to effect stabilization of the resulting high viscosity solution. A method for producing textured plasma protein on a laboratory scale is described, together with some of the properties of the resultant products.
Further experiments on the hot‐cutting of lamb
Authors: McLEOD K. , GILBERT K. V. , FAIRBAIRN S. J. , LOCKER R. H.
Published: July 2010

If joints of lamb, prepared by hot‐cutting, are conditioned in a carton for 24 hr in air at 1 °C and subsequently frozen, all the meat is tender when roasted from the frozen state, and bacterial counts are acceptable. Legs or shoulders may also be frozen in a carton without conditioning, since toughening does not occur, due to skeletal restrain of muscles. However, it is necessary to condition double loins and double racks to maintain acceptable tenderness.

Distortion due to packing in a carton is not a problem with shoulders, double loins and double racks stacked on end, but occurs to a degree in legs. Experiments on cutting after accelerated rigor produced by electrical stimulation showed an improvement in the handling of legs and shoulders, but not loins. Brief blast chilling of a carcass while suspended from the pelvis allowed easy cutting, including long loins, but the rounded conformation characteristic of hot‐cut legs and shoulders is lost.
Measurement of the stickiness and other physical properties of bread crumb
Authors: McDERMOTT E. E.
Published: July 2010

A simple apparatus for measuring the stickiness, compressibility and resilience of fresh bread crumb is described. Results are discussed in relation to the α‐amylase activity of the flour, and to the early stages of bread staling.
The effect of dents on the vacuum of tin cans*
Authors: BASKER H. B. , BEN‐GERA I.
Published: July 2010

A method is presented for measuring the extent of dents in tin cans. The effect of such dents on ‘vacuum' and headspace measurements is discussed. The effect of temperature variations during testing is considered. A simple, accurate method for the determination of the capacity of tin cans is also presented.
Experiments with freezing of melon cubes in Israel*
Authors: ANGEL S. , PRÉAUD JEAN MARIE
Published: July 2010

Freezing experiments with Israeli varieties of melons were carried out to study the effects of presoaking and different methods of freezing, packing and defrosting on the organoleptic properties of defrosted cubes.

Presoaked fruit was preferred to the controls. Vacuum‐packed fruit was compressed, soft and watery. Nitrogen packed fruit was superior in taste, texture and appearance to the air packed. Fast defrosting resulted in a firmer, tastier product.
The influence of hygiene in catch handling on the storage life of iced cod and plaice
Authors: HUSS H. H. , DALSGAARD D. , HANSEN L. , LADEFOGED H. , PEDERSEN A. , ZITTAN L.
Published: July 2010

Investigations of commercial fisheries in the North Sea and the Kattegat show that the bacterial load of the fish as caught is generally low. Substantial bacterial infection may occur, however, during sorting, gutting and other fish handling on deck, depending on the hygienic standard on board.

The influence of the hygiene in catch handling on the storage life of iced cod and plaice was studied at all seasons of the year.

During the first week of iced storage, no difference was found in the eating quality and in the contents of TVA in plaice and TVB in cod, whether the initial bacterial infection was low, medium or high. The three levels of infection were the result of very clean, reasonably clean and very dirty handling conditions, respectively. During the second week of storage, little difference was found between fish handled under very clean or reasonably clean conditions. Very dirty conditions, however, resulted in a slightly faster decrease of quality and in 1–3 days reduction in the total storage life in ice.
Technological investigations into Cape hake: I. Chilling at sea for freezing ashore
Authors: BURT J. R. , DREOSTI G. M. , JONES N. R. , SIMMONDS C. K. , STROUD G. D.
Published: July 2010

Cape hake were treated in a variety of ways before stowage in ice or refrigerated sea water at sea and before handling and freezing ashore. The adverse effects on colour and gaping of delays before chilling, of holding ungutted and of storage before freezing are described. The qualities of a selection of end products –fillets cut from wet fish, fillets cut from thawed fish, thawed fillets, steaks– have been assessed and compared.
Fully automated analysis of amino acids in foods by ion exchange chromatography
Authors: DAVIES M. G.
Published: July 2010

A fully automated system suitable for the analysis of amino acids is described. A standard Technicon autoanalyser was modified by means of an automatic sample loading and programming device. The time for the analysis of a complete amino acid mixture has been reduced so that two analyses are completed in 4 hr. A data acquisition system was incorporated which enabled results to be calculated using an off‐line computer.
Migration of styrene monomer from packaging material into food. Experimental verification of a theoretical model
Authors: DAVIES J. T.
Published: July 2010

A standard equation for a diffusion process has been adapted to cover the conditions of certain simple extractability experiments in which components migrate from polymers into foods. Data obtained during previous work on the migration of styrene monomer from polystyrene into foods have been re‐examined in order to confirm the validity of the adapted equation. A computer was used to assist in evaluating the constants of the diffusion process using the derived mathematical expression. It was possible to relate the change in the diffusion coefficients to the interaction of certain foods with the polymer.
Dielectric loss as a parameter for the study of polymorphism in trierucin
Authors: PARKASH S. , BLANSHARD J. M. V.
Published: July 2010

The temperature dependence of the dielectric loss of trierucin has been used to confirm the existence of five polymorphic forms. Comparable studies of the temperature dependence of the permittivity were less informative.
Nutritional and chemical changes in heated casein
Authors: OSNER R. C. , JOHNSON R. M.
Published: July 2010

Samples of commercial casein were processed either in solution or dry at temperatures between 100° and 130° for up to 8 hr. Denaturation (loss of solubility) occurred mainly at 120° and 130° and was preceded by darkening and by changes in gel filtration pattern, which indicated that molecular association had taken place. In samples subjected to severe heat treatment there were significant losses of aspartic acid, threonine, serine, cystine, histidine and lysine but apparent increases in glycine and alanine. The relationships between the various changes are discussed.
Kinetics of moisture movement during air drying of sugar beet root
Authors: VACCAREZZA LUIS M. , LOMBARDI JOSÉ L. , CHIRIFE JORGE
Published: July 2010

The effect of several variables on the drying rate of sugar beet root slices has been investigated. The standard solution of the nonstationary‐state diffusion equation was used to analyse the experimental results during the initial phase of the falling rate period of drying.

It was found that Fick's law can be used to predict average drying time, internal moisture distributions and sample temperature during dehydration with reasonable accuracy, despite the complex nature of the mechanisms of moisture transport.
Effects on bovine 1. dorsi muscle of conventional and microwave heating
Authors: ROBERTS P. C. B. , LAWRIE R. A.
Published: July 2010

A sequence of adjacent samples of beef 1. dorsi muscle were alternately exposed either to conventional heating for periods of 0–70 min at temperatures between 45° and 90°C or to microwaves at a frequency of 2450 MHz for periods of 0–10 sec at power levels between 131 and 1050 W. Protein denaturation was assessed by measuring nitrogen distribution between sarcoplasmic and crude myofibrillar fractions and by electrophoresis; and concomitant superficial changes in free water and plasticity measured.

The attainment of a given temperature by microwave energy was associated with less detrimental change than when achieved by conventional heating; but this could be attributed merely to further progression of the same type of effects due to the time necessitated with the latter procedure and not to any qualitative difference. The findings suggest that microwave heating might permit microbial inactivation in meat products with minimum loss of organoleptic quality. It is also suggested that the observed initial resistance of myoglobin to heat denaturation and its subsequent loss of electrophoretic mobility between 75° and 88°C could be developed as an index of the temperature attained by meat products.
Post mortem changes and spoilage in rock lobster muscle
Authors: SIDHU G. S. , MONTGOMERY W. A. , BROWN M. A.
Published: July 2010

Glycolysis in rock lobster comprising the oblique extensor, oblique flexor and enveloping muscles of Jasus novae‐hollandiae was studied under anaerobic conditions at 20°, 15° and 0°C. After bisecting the muscles along the mediosaggital plane one section was treated by dipping for 4 min in 3% sodium chloride solution containing 15 ppm oxytetracycline (treated). The other (untreated) was immersed in sodium chloride solution containing no antibiotic. In the treated muscles lactate production showed a linear relation to the fall in pH over a range of 7·2–6·0, a fall in one unit of pH corresponding to 118 μmol of lactate per g of tissue. In spite of a relatively high production of lactate the ultimate pH did not fall below 6·0 because of a high buffering capacity of the muscle.

Breakdown of phosphoraginine and ATP and accumulation of lactate and inorganic phosphorus at 20° and 15°C followed patterns similar to those observed in mammalian and poultry muscle but at 0°C these processes were slowed down to a much greater extent. There was no accumulation of glucose 6‐phosphate.

Concentrations of arginine rose as a result of phosphoarginine breakdown in both treated and untreated samples. However, in the untreated samples at 20° and 15°C, arginine concentrations started to fall 24 hr post mortem probably due to bacterial attack; the fall being more rapid at 20°C.

When mounted in a specially designed rigorometer at 20° and 15°C the muscle strips started to shorten concurrently with only a slight drop in ATP concentrations. The extent of shortening did not exceed 10% of the original and in some cases the contraction was immediately followed by a slow lengthening.

The findings of this study are discussed in relation to glycolysis and rigor mortis in mammalian and fish muscles.
The effect of cycled‐pressure on drying conditions during freeze drying
Authors: GREENFIELD P. F. , MELLOR J. D.
Published: July 2010

Cyclic‐pressure freeze drying has been found to improve the drying rate compared to the constant pressure process. This is due principally to the increased thermal conductivity of the semi‐dried region which results from the cyclic operation. The pressure oscillation causes unsteady temperature and mass flux conditions within the material being dried. During the high pressure portion of the cycle, very little sublimation takes place and the temperatures within the material are raised. When the pressure is reduced the temperatures are reduced as sublimation occurs. The temperature oscillations were found to have the same period as the pressure cycles, but to lag behind because of the heat capacity of the material. Additionally, it was found that the cycling produced high intermittent loads on both the heating source and the vapour condenser.
Retention of aroma components in extractive drying of aqueous carbohydrate solutions
Authors: KERKHOF P. J. A. M. , THIJSSEN H. A. G.
Published: July 2010

A new drying technique, extractive drying, has been studied experimentally. The retention of the components methanol, n‐propanol and n‐pentanol in extractive drying of a model liquid food was investigated. The model liquid food consisted of an aqueous solution of mixtures of dextrin and malto‐dextrin, to which the alcohols were added in low concentrations. As extraction liquid polyethylene glycol (PEG) 400 was used. The solution to be dried was dispersed in the PEG in the form of droplets.

High losses of the alcohols were found when the feed droplets were distorted upon contact with the extraction liquid. This distortion does not occur when the viscosity of the feed solution is higher than approximately 150 cP. For such feed solutions, containing 40% water and on dry basis 25% dextrin and 75% malto‐dextrin, very high aroma retentions were found. The effects observed agree with the selective diffusion theory.
Production of an enzymic hydrolysate of casein on a kilogram scale
Authors: CLEGG K. MARY , SMITH G. , WALKER A. L.
Published: July 2010

The scaling‐up of a method for the production of an enzymic hydrolsate of casein is descrived; minor modifications of the laboratory procedure were required. The spray‐dried product is relatively free of the bitterness often associated with proteins subjected to enzymic treatment. The bacteriological load of the raw materials, the intermediate stages, and the final product was monitored.

The production of hydrolysed casein in quantity is providing an opportunity to investigate the dietary potential of pre‐digested protein for patients suffering from digestive disorders as a result of pancreatic malfunction.
Water vapour adsorption on whole corn flour, degermed corn flour, and germ flour
Authors: KUMAR MAHESH
Published: July 2010

Adsorption isotherms for whole corn, degermed corn, and germ flours were obtained at 78°F and 122°F and at relative humidities in the range of 11–97%. Various empirical equations for the isotherms were tried and the parameters were calculated for the equations. Brunauer‐Emmett‐Teller (BET) surface areas of the various materials were calculated to describe the sorption phenomenon. The BET surface areas based on water sorption were higher for degermed corn flour than for germ flour. The free energy changes for whole corn, degermed corn, and germ flours were determined and represented by empirical equations.
The incidence of Clostridium botulinum in Danish trout farms: I. Distribution in fish and their environment
Authors: HUSS H. H. , PEDERSEN ANETTE , CANN D. C.
Published: July 2010

Examination of four Danish trout farms demonstrated the presence of Clostridium botulinum in trout, the wet‐fish feed, farm waters, pond muds and invertebrates and in the soil of the area surrounding the farm. The incidence in 530 trout examined varied from 5‐100% in winter to 85–100% in late summer. Clostridium botulinum type E was the predominant type found.
The incidence of Clostridium botulinum in Danish trout farms: II. Measures to reduce contamination of the fish
Authors: HUSS H. H. , PEDERSEN ANETTE , CANN D. C.
Published: July 2010

A number of experiments have been carried out to develop methods for the reduction of the contamination of farmed trout by the food poisoning organism Clostridium botulinum.

Starvation studies of fish gave variable results. When carried out under hygienic conditions in artificial containers and a clean water supply the contamination was reduced. Gutting of fish, either by hand or machine, always reduced the contamination to a low level.

Quick liming effectively reduced the contamination of pond bottoms and may be useful as a control measure against Clostridium botulinum.
Pectinesterase activity in the component parts of different Israeli citrus fruit varieties*
Authors: CHILD GERDA ROTHS , MOYAL ZEHAVA , KARSENTY ANNA
Published: July 2010

Pectinesterase activity in whole fruits and single fruit components was established for grapefruit and orange (shamouti and valencia) varieties. It was found to range, in terms of pectinesterase units per gram of test material, from PE.u. x 104=5·1 for hand‐reamed or 11·2 for commercially extracted juice to PE.u. x 1044=821 for pulp and rag. Enzyme activity in each of the different components was highest in valencia. The comparative distribution of component activity was similar for all three fruit varieties. When test materials of low pH were allowed to stand even for short periods prior to examination, partial inactivation occurred, whereas at pH 3·5 and above, pectinesterase activity remained stable for 8 hr or more. Therefore, in order to obtain reproducible results, stabilization of the more acid samples by raising the pH level to at least 3·5 was necessary.
Collagen fibre arrangement in intramuscular connective tissue. Changes associated with muscle shortening and their possible relevance to raw meat toughness measurements
Authors: ROWE R. W. D.
Published: July 2010

Collagen fibres of ovine and bovine perimysium are shown to have a crimped appearance. The size of the crimp is smaller than in the collagen fibres from tendon (e.g. perimysium 19 μm; tendon 79 μm). The collagen fibres are laid down in a well‐ordered criss‐cross lattice at an angle to the muscle fibre long axis. Muscle contraction changes the angles of this lattice and also changes the crimp length. These changes are related to differences between samples of meat of uniform size such as are tested for toughness. It is demonstrated that any explanation of changes in meat toughness resulting from shortening can no longer be related only to changes in ‘myofibrillar toughness’, but must also include extensive changes in ‘connective tissue toughness’.
Retention of volatile organic compounds in a complex freeze‐dried food gel
Authors: KAYAERT G. , TOBBACK P. , MAES E. , FLINK J. , KAREL M.
Published: July 2010

The retention of 14G‐labelled ethyl acetate, n‐propanol and acetone in freeze‐dried food gels is studied. Fractional retention of the initially present volatiles increases with increasing solids concentration and decreases with increasing initial volatile content. Retention also decreases with increasing sample thickness in fast‐frozen samples, and is lower in rapidly frozen than in slowly frozen samples.

Humidification causes release of retained volatiles, the new level of retention depending upon relative humidity. The results indicate that the predominant retention mechanism is entrapment in microregions, with a small contribution due to adsorption.
The vitamin C content of quick frozen green beans
Authors: MORRISON MARY H.
Published: July 2010

The effect of maturity, variety, post‐harvest delay and various stages in processing, including cleaning, blanching and end‐cooking, on the vitamin C content of quick frozen green beans (Phaseolus vulgaris) has been studied. The vitamin C content of eight varieties showed considerable variation but no correlation with maturity was observed. Post‐harvest delay and processing caused a noticeable reduction in vitamin C content. The overall retention of vitamin C in both whole and sliced frozen beans was approximately 75%. After cooking, fresh manually sliced beans retained 59% of the original vitamin C content compared with 44% for the commercially frozen sliced beans.
Pasteurization conditions for juices and comminuted products of Israeli citrus fruits*
Authors: ROTHSCHILD GERDA , VLIET CHRISTINE VAN , KARSENTY ANNA
Published: July 2010

Time‐temperature curves were established for heat inactivation of pectin‐esterase in citrus juices and comminuted materials of different citrus varieties, pH, and enzyme activities; a highly sensitive analytical method was used as criterion for adequacy of pasteurization. Inactivation temperatures were lower in materials of lower pH, ranging from 75 to 90° for juices and 80 to 95° for comminuted products. But, in order to exploit the‘low pH‐low temperature effect, longer holding times had to be applied to the more acid test materials. Fifteen sec were sufficient for orange juice, and longer holding times had no effect on the inactivation temperature required for this variety (90°). However, for grapefruit juice, an increase in holding time, e.g. from 15 to 30 sec resulted in an inactivation temperature change from 90° to 85° and from 90° to 80° for lemon juice.
The analysis of strawberries as a means of determining the fruit content of manufactured products
Authors: GOODALL H. , SCHOLEY J.
Published: July 2010

Multivariate statistical analysis was examined as a means of obtaining more reliable assessments of fruit contents from analytical determinations than are possible by the current use of average values of insoluble solids, nitrogen, phosphorus and potassium contents. The major portion of the investigation dealt with the fruit itself.

Twenty‐three parameters were determined on fifty‐four samples of strawberries, culled during three successive seasons, and representing a wide span of cultivars, their origins and growing areas. To derive the weighting factors to be applied to the analytical determinations in order to obtain the optimum estimate of fruit content, the analytical results were submitted to multivariate statistical analysis. This approach led to a marked improvement in the estimations of fruit content when compared with conventional techniques.

Wide variations were found in the levels of all of the parameters determined, but there were highly significant correlations between many pairs, in which the free amino acids figured largely. A limited study to assess the usefullness of these parameters for determining the fruit content of manufactured products showed that the amount of free amino acids recovered from fresh fruit jams and from frozen fruit were very similar. However, the amounts recovered from sulphited pulp and sulphited fruit jams did not fall into any clear pattern. Further investigation of the effect of sulphiting on the free amino acids is therefore necessary before the statistical approach can be applied in these circumstances.
The production of polyunsaturated tallows and their utilization in margarine manufacture
Authors: HERBERT L. S. , KEARNEY K. J.
Published: July 2010

Offal materials were collected from sheep and cattle, which had been slaughtered after a period of feeding with a protected polyunsaturated oil supplement. Tallows produced from these offals by methods simulating batch dry rendering and low temperature wet rendering processes contained about 19% linoleic acid and had a saturated/unsaturated ratio lower than in normal tallows. Pilot scale refining and margarine manufacturing processes were used to convert the tallows to margarines. No unusual or unexpected processing or quality effects are expected in commercial production using standard ‘good practice’ rendering, refining and margarine manufacturing procedures.
A national survey of muscle pH values in commercial pig carcasses
Authors: KEMPSTER A. J. , CUTHBERTSON A.
Published: July 2010

Measurements of muscle pH at 45 min post mortem (pH1) and after overnight cooling (pH2) were taken in a total of 6015 commercial pig carcasses at sixteen bacon factories in Great Britain. Measurements were made in the M. longissimus in the area of the last rib and in the M. semimembranosus.

Differences between muscles in the overall distribution of pH1 and pH2 were negligible. The overall mean for pH1 measured in the M. longissimus was 6.55 ± 0.32 (s.d.) and 5.7% of the values were below pH 6.0. The overall mean for pH2 in this muscle was 5.81 ± 0.25 and 2.1% of the values were above pH 6.5. Wide differences were recorded between factories in the distribution of pH1 values; means ranged from 6.98 to 6.20 and the percentage of values below pH 6.0 from 0.3 to 20.6.

pH was independent of muscle temperature and carcass weight. Low and positive correlations were recorded between pH measurements and backfat thickness.

Comparison of the overall results with those of a similar survey carried out in 1964 indicated that the distribution of pH values in commercial British pigs has changed very little in the last decade.
The Stomacher—its use for homogenization in food microbiology
Authors: TUTTLEBEE J. W.
Published: July 2010

A new homogenizer, the Stomacher, was compared with other methods of homogenization. Various food samples were homogenized on the Stomacher and also in Ato‐mix blenders (prawns and other cooked foods) by simple mixing (raw meats, powdered egg and milk), or by using a pestle and mortar (cheese).

Microbiological examination of various foods indicated that the Stomacher released significantly larger numbers of viable micro‐organisms, calculated on the basis of a colony count, than other methods of homogenization, except from samples of cheese and powdered egg and milk. The advantage of using the Stomacher is that no sterilization or maintenance is required as with Ato‐mix blenders and other equipment.
Scanning electron microscope studies of membrane deposits from whey ultrafiltration
Authors: LEE DORETTA N. , MIRANDA MARY G. , MERSON RICHARD L.
Published: July 2010

Scanning electron microscopy (SEM) was used to study the fouling deposits from cottage cheese whey on ultrafiltration membranes. Several types of deposits were observed: micro‐organisms, granules, thin strands, coarse fibres and sheets of varying thickness. Surface deposits of sheet forming materials appear to be the principal cause of membrane flux decline. The progressive build‐up of deposits was demonstrated directly on ultrafiltration membranes and by simulation of fouling on membranes having uniform pores discernible by SEM. SEM was found to be a simple and effective tool for study of membrane fouling.
Wiltshire curing with and without nitrate
Authors: TAYLOR A. A. , SHAW B. G.
Published: July 2010

Unsmoked bacon has been made by a factory Wiltshire process incorporating hand pumping and immersion using brines with and without nitrate and with diminishing concentrations of nitrite. The quality and stability of the bacon during storage in vacuum packs has been compared.

Curing with a nitrate‐free brine containing 26% salt and 1000 ppm nitrite produced back bacon with 57–81 ppm nitrite and approximately 4% salt in the lean and this, when sliced and vacuum packed, was still acceptable after 5 weeks at 5°C and 2 weeks at 15°C. Brines with nitrite concentrations of 500 ppm and less gave back bacon which was more prone to souring during storage due to increased growth of lactic acid bacteria.
The ascorbic acid content of quick frozen Brussels sprouts
Authors: ABRAMS C. I.
Published: July 2010

The effect of maturity, variety, stage of the season, post‐harvest delay, processing procedures and end‐cooking on the ascorbic acid content of commercially quick frozen Brussels sprouts has been studied. The ascorbic acid content of sprouts decreased with increasing size and the distribution of the vitamin within the sprout showed the meristem to have the highest concentration which decreased through the inner light green leaves to the outer dark green leaves. The progressive reduction in ascorbic acid content during the 3 1/2 month harvesting period prevented the establishment of any significant findings for differences in the nutrient level of nine varieties of Brussels sprouts. Post‐harvest delay caused no reduction of ascorbic acid content and, during processing, losses were only incurred at the blanching stage. Retention values of 76‐89% ascorbic acid on a dry weight basis were found in the frozen product and, after cooking, fresh and frozen sprouts reained 59‐64% of the original vitamin C content. Loss of ascorbic acid due to leaching during commercial processing and end‐cooking appears to be considerably less for sprouts than for sliced green beans and marginally less than for peas.
The gas chromatographic determination of trimethylamine and dimethylamine in fish, fishery products and other foodstuffs
Authors: RITSKES T. M.
Published: July 2010

Baseline separation of trimethylamine (TMA) and dimethylamine (DMA) is obtained on a Carbowax 400/polyethylene imine column provided with an alkaline pre‐column. Based on this separation, a method of analysis for these amines in fish and other foodstuffs was worked out.

Quantitative distillation of traces of DMA could be achieved by addition of ethylamine prior to distillation. A sensitivity increase up to the ppm range was found to be possible. Amine oxides, after reduction with titanous chloride, can be determined in the same way. The automation of the gas chromatographic injection procedure is described.
Ultrastructural changes during frozen storage of cod (Gadus morhua L.)
Authors: JARENBÄCK L. , LILJEMARK A.
Published: July 2010

The ultrastructure of myofibrils from cod white muscle has been studied using the freeze etching technique. Unfrozen post‐rigor samples were compared with thawed samples stored for a short period at −40°C and also with samples stored at −20°C for a period known to result in severe toughness.

Transverse fractures from unfrozen muscle reveal the regular hexagonal arrangement of thick myofilaments and the vesicular material of the sarcoplasmic reticulum between the myofibrils. Muscle stored for a long period at −20°C shows, after thawing, disturbances in the hexagonal pattern and deformation of the sarcoplasmic reticulum. Longitudinal fractures both from unfrozen and frozen stored muscles sometimes reveal the arrangement of cross‐bridges between thick and thin myofilaments. Gross‐bridges lie at an angle to the thick filaments and their repeat along the filament can be seen.

Measurements of distances between thick myofilaments showed a significant reduction in the interfilament spacing after prolonged frozen storage. This shrinkage together with the observed disorders within and between myofibrils may reflect an impaired ability to reabsorb water following thawing.
The effect of plating technique and incubation temperature on bacterial counts
Authors: NOTTINGHAM P. M. , RUSHBROOK A. J. , JURY K. E.
Published: July 2010

A comparison of plating methods and incubation temperatures for aerobic bacterial counts, carried out on samples from lamb, beef and meat processing equipment, showed that the spread plate counts were generally higher than those by the pour plate procedure. This was particularly so for samples which had been exposed to low temperatures for long periods. Incubation of plates at 25 and 30°C gave similar results but the 37°C counts were usually lower and more variable. Replication of dilutions or plates was found to give little or no increase in accuracy.
Water sorption isotherms in sugar beet root
Authors: IGLESIAS HÉCTOR A. , CHIRIFE JORGE , LOMBARDI JOSÉ L.
Published: July 2010

The water sorption isotherms of raw sugar beet root and its water insoluble components, at various temperatures, were determined. An attempt is made to describe the experimental equilibrium moisture content data using some existing theories on physical adsorption.
Ultrastructural changes during frozen storage of cod (Gadus morhua L.)
Authors: JARENBÄCK L. , LILJEMARK A.
Published: July 2010

Myofibrillar proteins from post‐rigor unfrozen and stored frozen cod muscle have been studied by electron microscopy. Changes in extracted proteins and corresponding myofibril residues were followed by negative staining and ultrathin sectioning throughout a frozen storage period of 120 weeks.

In myofibrillar extracts a decrease in the number of actomyosin filaments and an increase in the number and size of large aggregates was found. A decrease in the length and amount of attached myosin was noticed in actomyosin filaments. The changes observed were most extensive at — 10°C, less pronounced at — 20°C and hardly noticeable at — 30°C.

According to the appearance of the myofibril residues thick myofilaments had been almost completely extracted from unfrozen muscle and were increasingly resistant towards extraction the higher the temperature during frozen storage.
Cooking shortening and the toughening of beef
Authors: DAVEY C. L. , GILBERT K. V.
Published: July 2010

The relationship between cold‐shortening and toughness has been determined for the sternomandibularis muscles of young ox cooked at both 60 and 80°C, and therefore taken through the recently established first and second stages of cooking toughness development respectively.

At both cooking temperatures, toughness increases approximately three‐fold on shortening to 35‐40%, and declines steeply at higher shortenings. At a given shortening, the toughness of meat taken through the first cooking stage is only half that of meat taken through both stages. The pronounced cooking shortening accompanying the second stage contributes to toughness to virtually the same degree as cold‐shortening in pre‐rigor muscle.

On the basis of this observation toughness has been related in general terms to muscle structure and function. The mechanics of cleaving cooked meat across the grain and of how shearing force increases with shortening are also discussed.
Colour retention in fresh meat stored in oxygen—a commercial scale trial
Authors: MACDOUGALL D. B. , TAYLOR A. A.
Published: July 2010

Aged fresh beef was conventionally packaged at a central cutting plant and transported in oxygen filled containers to a retail outlet where it was compared in a refrigerated display cabinet with similar meat held in air. Colour deterioration during transport and storage was successfully delayed by holding in oxygen and the process was most effective in muscles prone to rapid discolouration. Even a small rise in temperature accelerated discolouration so that good refrigeration during display was still essential.
The effect of extraction, animal age and post mortem storage on tendon collagen. A differential scanning calorimetric study
Authors: LEDWARD D. A. , CHIZZOLINI R. , LAWRIE R. A.
Published: July 2010

Differential scanning calorimetry was used to study the collagen → denatured collagen transition in tendon collagen. It was found that purification of collagen by salt (KCI) and trypsin caused a slight, but significant, decrease in the transition temperature, but no significant change in the enthalpy, ΔHD, of the transition.

Animal age (0‐6 years) had no significant effect on either ΔHD (mean value = 1293 ± 72 cal. amino acid residue−1) or the extrapolated onset temperature, T0, (334.2 ± 0.3°K) of the transition in untreated tendon. However, the amount of collagen melting after 340°K increased markedly with age (from 0 to about 250 mg/g of tendon) although the amount melting before 340°K was approximately constant, 138 ± 17 mg/g tendon.

Upon storage at 1 ± 1°C for 2 weeks 7 out of 16 tendons became less stable as judged by decreases in T0 and increases in the amount of collagen melting before 340°K. Two of the tendons became more stable as judged by increases in T0 and decreases in the amount melting before 340°K. These results are briefly discussed.
The heating of foodstuffs in a microwave oven
Authors: KIRK D. , HOLMES A. W.
Published: July 2010

A method for calculating the temperature profile in a solid material after a period of microwave heating is described. The calculation incorporates internal heat generation, caused by the microwave radiation, together with other forms of heat transfer. It is shown that the calculated profile, based on the dielectric and thermal properties of water, agrees with experimentally measured temperature profiles in gels of 1% Ionagar in water.
Yeasts in ginger storage brines
Authors: LLOYD ANNICE C.
Published: July 2010

When green ginger rhizomes were stored in acidified salt brines (7‐9%) a short vigorous yeast fermentation was obtained. The yeasts present and the changes in yeast flora during the fermentation period were investigated.

Fifty‐seven yeast cultures isolated from the brines were classified in the following genera: Candida (24 isolates), Pichia (21 isolates), Hansenula (11 isolates) and Rhodotorula (1 isolate). During the early part of the fermentation, Candida species (mainly C. tropicalis) predominated, whereas towards the end of fermentation the more salt tolerant Pichia species (e.g. P. ohmeri) predominated.
Effects of γ‐irradiation on quality and enzyme activities of prepacked cut chicory
Authors: TANAKA YOSHIKAZU , LANGERAK DICK IS.
Published: July 2010

The effects of γ‐irradiation on quality and enzyme activities of prepacked cut chicory were investigated. Freshly cut slices of chicory were washed, centrifuged and packed in polythene bags. These samples were γ‐irradiated and stored in the dark at 10°C. The samples were tested organoleptically and the peroxidase and polyphenoloxidase activities were determined. The chlorogenic acid content was also measured.

The results showed that, as far as the keeping quality of the prepacked chicory was concerned, 100 krad irradiation was superior to both the 0 krad and the 300 krad treatment, but irradiation in perforated bags (high O2 content) increased discolouration (browning). Peroxidase and polyphenoloxidase activities did not change for about two days after irradiation in the perforated or non‐perforated bags. These activities increased strongly in the non‐irradiated series. Some chicory was treated with cystein and NaCl in order to inhibit some of the discolouration, but rotting of this sample occurred sooner than in non‐irradiated samples. No difference in the chlorogenic acid content was found as a result of irradiation.
The relationship between respiration, atmosphere and quality in intact and perforated mushroom pre‐packs
Authors: NICHOLS R. , HAMMOND J. B. W.
Published: July 2010

Fresh ‘button’ mushrooms (Agaricus bisporus) were stored at 18°C in pre‐packs overwrapped with one of six polylvinyl chloride films. The effect of piercing the film with one to four pinholes (punctures) on the concentrations of CO2 and O2 in the pre‐pack atmosphere and the internal browning and CO2 production of the packed mushrooms were measured.

The respiration, as measured by CO2 production, of mushrooms in intact packs was depressed by over 50% from the values observed in air, and varied considerably between the films used. There appeared to be an inverse relationship between respiration in the pre‐pack and internal browning. Carbon dioxide output of the packed mushrooms increased as a result of perforating the overwrapping film. The effect of perforations on the CO2 and O2 concentrations in the pre‐pack atmosphere and on the internal browning of packed mushrooms depended on the type of film used. It appeared that one or two pinholes in films which permitted low respiration rates when intact, caused a rise of CO2 concentration and an increase in internal browning, while little change was seen in O2 level; more pinholes led to a decrease in CO2 concentration, an increase in O2 concentration and some decrease in internal browning. Pre‐packed mushrooms overwrapped with a film which permitted a high level of respiration when intact showed decreased CO2 and increased O2 concentrations and some decrease in internal browning at all levels of perforation.

The significance of the results is discussed in relation to previous work and to commercial practice.
Ultrastructural changes during frozen storage of cod (Gadus morhua L.)
Authors: JARENBÄCK L. , LILJEMARK A.
Published: July 2010

Myofibrils and solutions of myofibrillar protein from post‐rigor cod muscle were studied with electron microscopy after incubation with linoleic acid and linoleic acid hydroperoxides.

Linoleic acid hydroperoxides were ten times more effective than linoleic acid in reducing the amount of protein in KCl‐extracts from incubated myofibrils. Small quantities of hydroperoxides caused precipitation of isolated myofibrillar proteins.

Differences in the structure and aggregation pattern of extracted proteins suggest that linoleic acid and hydroperoxides exert their effects by different mechanisms. According to the structure of extracted myofibrils, linoleic acid seemed to prevent the dissolution of the myofibril framework but appeared not to impair the extraction of myosin. Hydroperoxides appeared to cause a retention of A‐bands (myosin) in the myofibrils and in this respect showed similarities to the effect of frozen storage previously observed.
Utilization of edible protein from meat industry by‐products and waste
Authors: YOUNG R. H. , LAWRIE R. A.
Published: July 2010

Proteins isolated in quantity from porcine lung and stomach have been modified into fibrous forms. Stable dispersions could be prepared from the isolates on alkali treatment, the final viscosity depending upon protein and alkali concentration and the pH of isolation. Fibrous products spun from these protein sources appear to have lower elasticity than those spun from concentrated blood plasma. The spinning of admixtures of lung and stomach proteins with plasma gave rise to poor mechanical properties in the resultant fibres. However, amino acid analysis has indicated that such procedures effectively supplement isoleucine and methionine, deficient in spun plasma products.
Bacterial infection/invasion in fish flesh
Authors: HERBORG L. , VILLADSEN A.
Published: July 2010

Experiments with mechanical treatment of trout have been carried out to show whether there exists any correlation between the stress of the animal before death and the level of bacterial infection in the flesh and/or the quality of the fish determined by organoleptic assessment.

The quality and keeping time of the trout is reduced when the fish is exposed to physical stress. The reduction increases with increasing mechanical treatment and is bigger in feeding than in starving fish.

The infection level in the fish muscle increases with increasing physical stress and is higher for feeding than for starving trout.

When the count of bacteria is higher than 100/g there is a very good correlation between the log count and the organoleptic score.
The effect of smoking and drying on the lipids of West African herring (Sardinella spp.)
Authors: WOOLFE M. L.
Published: July 2010

The fate of the lipids of smoke dried Sardinella aurita has been investigated. Peroxide values showed that smoke drying initiated lipid oxidation. Crude fractionation of the lipids showed that the site of initiation was bound lipids in contact with the proteins. Comparison of the oxygen uptake of smoke dried fish under different time‐temperature conditions indicated that final moisture content was the predominant factor affecting rate of oxidation. The use of smoke did not appear to affect the rate of oxidation.