bluuebunny/crossref_metadata_2025 huggingface dataset:
The production of pito, a Nigerian fermented beverage
Authors: EKUNDAYO J. A.
Published: July 2010

Summary. The traditional method for preparing pito, a Nigerian fermented beverage, from maize, sorghum or a mixture of both, is described. Pito was prepared from maize in the laboratory and microbiological aspects of the process investigated. the conversion of starch to sugars during steeping and malting appears to be due partly to enzymes in the grain and partly to moulds (Penicillium spp., Rhizopus oryzae and Aspergillus sp.) present on the surface of the grain. the first stage of fermentation of the extract from the malted grain, souring, is dependent upon micro‐organisms from the atmosphere and a second stage, after boiling to concentrate, on the addition of a ‘starter’ from a previous brew. Candida sp., Geotrichum candidum and Lacto‐bacillus sp. appear to be important in both stages, and result in the production of lactic acid and about 3% alcohol. the production of alcohol and organic acids by inoculation of sterile extracts of malted grain by pure cultures of the above organisms was demonstrated.
A lipid analysis of the Greater Silver Smelt [Argentina silus (Ascanius)] and an evaluation of its potential for food and fish meal production
Authors: MACKIE P. R. , HARDY R.
Published: July 2010

Summary. Samples of the fish species Argentina silus (Ascanius) have been studied for utilization as a food fish and also for the production of fish meal. the flesh was found very acceptable by taste panels, but because of its unsaturated oil content, rancidity would occur during long‐term storage unless precautions were taken to reduce this spoilage.

The lipid content and composition of this fish together with the amino acid composition has been measured. the results indicate that fish meal produced from it would be nutritious and have a relatively high oil content, if the fish was not processed as a fatty fish.
The phenolic compounds of blackcurrant juice and their protective effect on ascorbic acid
Authors: HARPER K. A. , MORTON A. D. , ROLFE E. J.
Published: July 2010

Summary. The oxidation of ascorbic acid in citrate buffer at pH 2.9 has been investigated with and without added copper ions as catalyst, and the loss of ascorbic acid followed by polarographic analysis. Certain flavonoids occurring in blackcurrant juice were used as antioxidants and their activity, in the absence of added copper ions, was found to decrease in the order, quercetin and dihydroquercetin (equal), kaempferol and rutin. Cyanidin‐3‐rhamno‐glucoside and delphinidin‐3‐glucoside accelerated the oxidation. In the presence of added copper ions quercetin showed increasing antioxidant activity up to 12.5 × 10‐5M (7.8 : 1, quercetin‐copper ratio) after which the activity decreased rapidly. Anthocyanins were shown to possess slight antioxidant activity in the presence of copper ions. the probable mechanism of ascorbic acid oxidation is outlined, and the mode of action of flavonoids as antioxidants discussed.
Hydrogen sulphide in cooked chicken meat
Authors: PARR L.J. , LEVETT G.
Published: July 2010

Summary. Precautions necessary for the determination of hydrogen sulphide in chicken meat are outlined and data given for its production during heating and subsequent disappearance on standing.
Forced convection ovens for reheating pre‐cooked frozen food
Authors: WALKER R. B. , GLEW G.
Published: July 2010

Summary. The importance of food pack thickness in forced convection ovens is shown in relation to production rates. For ovens operated on a batch basis, a pack thickness of 16 mm was recommended, and for ovens operated on a continuous basis, a pack thickness of 10 mm was recommended.

A method for evaluating forced convection ovens was developed and applied for five commercially available ovens which were then compared. the ovens with fans external to the oven cavity and with the air flow ducted across the trays were superior to the ovens with fans built into the oven cavity. the fastest reheating was 25 min for the ducted air type and 35 min for the stirred air type. the most uniform reheating occurred in the ducted air type of ovens.
A mathematical model of the Torry fish drying kiln
Authors: DOE P. E.
Published: July 2010

Summary. Proposed developments of the Torry fish drying kiln have led to a need for a closer understanding of commercial fish drying processes. In order to investigate the effects on fish drying of air velocity, air temperature and humidity, and fish packing density, a mathematical model of the kiln has been proposed. This model establishes partial differential equations for fish weight, air temperature and humidity. the model is applicable to the drying of other materials. A solution is obtained numerically by standard finite difference techniques.
The use of sorbic acid in salted fish
Authors: DOESBURG J. J. , LAMPRECHT E. C. , ELLIOTT M. C. , REID D. A.
Published: July 2010

Summary. It has been shown that the development of Hemispora stellata Vuill and red halophilic bacteria in salted snoek (Thyrsites atun Euph.) can be combated successfully by the use of sorbic acid during salting of the fish. Applications of sorbic acid by dipping of the fish in salt‐sorbate solutions proved to be more effective than the use of a mixture of salt and sorbic acid in the salting of fish. When the preservative was mixed with the salt, a severe breakdown of sorbic acid, catalysed by fish constituents which migrated into the salt, occurred during salting. In contrast with this the sorbic acid in salted fish was shown to be rather stable.

Though the experiments were confined to limited experimental saltings, and some of the statements might not hold completely for full scale salting, it should be mentioned that in practice the application of dipping in salt‐sorbate solutions also gave good protection against development of halophilic moulds and bacteria.
Rheological characteristics of processed whole egg
Authors: CORNFORD S. J. , PARKINSON T. L. , ROBB J.
Published: July 2010

Summary. Flow curves determined with a rotational Viscometer have shown that unfrozen raw and pasteurized liquid whole egg are Newtonian fluids and that thawed frozen whole egg is pseudo‐plastic. For the latter a useful value for comparative purposes may be obtained by calculating the apparent viscosity at a selected low rate of shear. Some preliminary results illustrate the very large difference in viscosity between unfrozen egg and thawed frozen egg.
The morphological changes produced in cauliflower stems during pickling, and their relationship to texture parameters
Authors: SAXTON C. A. , JEWELL G. G.
Published: July 2010

Summary. The changes in morphology and texture which occur during the pickling of cauliflower have been studied using the electron microscope and Instron Universal testing rig.

It has been shown that the marked changes in the texture parameters, hardness, elasticity and cohesion, during the initial 24 hr in brine, correlate with plasmolysis of the tissue and re‐organization of cell wall materials. At the end of the 1st week in brine, with the disruption of the protoplast, the only intact organelles were the spherosomes. the cell walls became extremely thin in the pit field regions, and it was to these areas that the spherosomes tended to migrate. the disruption of the spherosomes, during the 4th week in brine, with the possible release of hydrolytic enzymes may have contributed to the further weakening of the cell wall.

The use of electron histochemical stains has permitted the demonstration of the gradual degradation of pectic substances, resulting in enlarged intercellular spaces and a decrease in tissue cohesion. By staining neutral polysaccharides, it has been shown that the cell wall materials are not degraded to a marked extent and hence would add little to the sugars available for bacterial fermentation.

The increase in crispness, said to arise from freshening and acidification, is not just a simple recovery in turgor pressure, since the protoplast plasmalemma quickly loses its semi‐permeable characteristics and is later destroyed. However, an enhancement of elasticity and tissue cohesion has been demonstrated by using freshening solutions containing 2500 ppm calcium.
Copper‐flavonoid complexes in acidic solutions
Authors: HARPER K. A.
Published: July 2010

Summary. Amperometric titration was used to detect complexing of cupric ions by flavonoids in solutions more acid than pH 4.5. Strongest complexing ability was shown by the 3‐hydroxy‐4‐carbonyl system although the 5‐hydroxy‐4‐carbonyl system also complexed with copper in acid solution. the o‐diphenolic grouping did not form complexes under the conditions used. Complexing ability was enhanced by the presence of hydroxyl groups in conjugation with the carbonyl group. Quercetin was the only flavonoid tested capable of complexing copper at pH 2.3. the significance of these results to the antioxidant action of flavonoids in fruit juices is discussed.
Effect of chilling shrinkage of pig carcasses on yield of Wiltshire bacon
Authors: COOPER T. J. R.
Published: July 2010

Summary. Twenty pig carcasses were taken fresh from the slaughterline and split into two sides. One‐half of each pig was quick‐chilled and the other rapidly chilled. Trimming, brine injection and curing were closely controlled and weights at various stages of processing were accurately measured.

Overall, there was no difference in the final weight of bacon produced by the two chilling systems. There was some variation in the curing weight loss of different pigs, pH appearing to be a factor.
Quantitative identification of meat species after heating
Authors: MATTEY MARY , PARSONS A. L. , LAWRIE† R. A.
Published: July 2010

Summary. A method, based on laser densitometry of starch gel electrophoretograms of proteins extractable in 8 M urea, is described for the quantitative identification of ox and rabbit in mixtures of meat from these species heated at 120°C for 3‐6 min. It is suggested that the method could be developed for the analysis of unknown mixtures of proteins heated for as long as 20‐25 min at such temperatures.
Spontaneous heating in meat
Authors: JARVIS H. F. T.
Published: July 2010

Summary. The heat released in biochemical reactions immediately after slaughter apparentlyraises the carcasstemperatureinitially by a degree or two Centigrade. No further significant heat is produced in small samples, kept under near‐adiabatic conditions at various ambient temperatures, until bacterial numbers reach 109/g. Treatment of samples with antibiotics and restriction of oxygen supply reduce heat production. the release of heat by a putrid carcass is unlikely to affect the temperature of adjacent meat significantly, and in no circumstances could frozen meat that is not putrid produce sufficient heat to thaw itself.
The use of Thiabendazole for the post‐harvest treatment of bananas
Authors: BAILEY DIANA M. , GUTTS D. F. , DONEGAN L. , PHILLIPS C. A. , POPE R.
Published: July 2010

Summary. Studies were carried out to assess the efficacy of thiabendazole (TBZ or [2‐(4‐thiazolyl)benzimidazole]) in controlling fungal rot damage of bananas in the Windward Islands. A dipping treatment proved to be more effective, especially in the reduction of rot in the banana cushions, than application of the fungicide by spraying, but both methods of application resulted in a very satisfactory control of fungal rots. Chemical analysis of the treated bananas showed that regardless of mode of application and location on the hand the residue levels were well below the limits permitted by American standards.
Aroma retention during the drying of liquid foods
Authors: MENTING L. G. , HOOGSTAD B. , THIJSSEN H. A. C.
Published: July 2010

Summary. Factors determining aroma retention during the drying of food liquids have been investigated with the aid of a model system. Slabs of an aqueous solution of partially hydrolysed starch, containing a small amount of acetone, were dried in air and the percentage of acetone retained was measured.

Acetone was lost almost exclusively during the ‘constant‐rate’ period of drying and its rate of loss could be described in terms of a binary diffusion process. At high moisture contents, the rate of loss of a component from a drying solution is mainly dependent on its volatility, while at low moisture contents the diffusion coefficient of the component becomes the determining factor.

Loss of volatile components will be only very slight if, at the onset of drying, the value of the dimensionless group BiwoKwo is sufficiently large. Here BiBiwo is the Biot number for water transport and Kwo is the ratio of the equilibrium water concentration in the gas phase and the water concentration in the solution to be dried. the minimum value of the group necessary to ensure high aroma retention increases with increasing relative humidity of the drying air. This value is larger for a drop than for a slab and is equal to 22 for a droplet under normal spray‐drying conditions.
Effect on various spoilage values of the addition of sulphite and chlortetracycline to beef stored at 5°C
Authors: PEARSON D.
Published: July 2010

Summary. Methods for determining various chemical spoilage values in meat, previously considered in some detail by the author, have been applied to various samples of beef to which sulphur dioxide and chlortetracycline had been added.

The incorporation into minced beef of these preservatives when compared with the effect on untreated meat, caused retardation of proteolytic breakdown as measured by the relative increases of the total volatile nitrogen during storage. There was also a corresponding delay in the fall of the extract‐release volumes. Concurrently fat hydrolysis increased at a considerably faster rate than the controls.
The equilibrium water vapour pressure of frozen cod
Authors: STOREY R. M. , STAINSBY G.
Published: July 2010

Summary. The equilibrium water vapour pressure of frozen cod has been measured and found to be equal to that of ice at the same temperature. the concentration of solutes in unfrozen cod, calculated from a plot of the fraction of unfrozen water remaining and the relative lowering of the vapour pressure of supercooled water to that of ice at the same temperature, is equivalent to a 1.34% solution of sodium chloride. This value is in good agreement with values obtained by other workers.
Estimation of volatile onion aroma and flavour compounds
Authors: SAGUY M. , MANNHEIM C. H. , PELEG Y.
Published: July 2010

Summary. The Chemical Oxygen Demand (COD) method was used for the evaluation of onion aroma components. the method was found to be reliable and to correlate well with odour threshold values for raw onions and with taste scores for dehydrated onion products. Odour threshold values could not be used for the latter products due to the development of undesirable off‐odour after exposure to high temperature or prolonged storage.
Chlorophyll, colour and pH changes in H.T.S.T. processed green pea puree
Authors: BUCKLE K. A. , EDWARDS R. A.
Published: July 2010

Summary. Pea puree of pH 6.95 and pH 8.45 was heat processed in thermal death‐time tubes at temperatures between 115.6°C and 148.9°C to a process value of F0= 6.0. Chlorophyll pigments, Hunterlab colour indices and pH were determined before and after high temperature‐short time (H.T.S.T.) processing and during storage for 18 months at 20°C, 2.8°C, and −23.3°C.

Highly significant correlations were found between per cent conversion of chlorophylls to pheophytins and objective colour indices derived from tristimulus measurements on stored pea puree. the degree of chlorophyll conversion, and hence puree colour, were both markedly affected by process temperature, product pH, storage time and storage temperature, but long‐term storage stability was achieved only by combinations of two or more variables.

Changes in pH of processed and stored puree were directly related to changes in pigments and colour, and it appears that pH control during processing and storage offers the most likely means of colour and pigment retention in heat processed chlorophyll‐containing foods.
A study of the natural disappearance of the limonin monolactone in the peel of Shamouti oranges
Authors: FLAVIAN SOLANGE , LEVI A.
Published: July 2010

Summary. A previously unknown process has been found to occur in the peel of Shamouti orange at the end of the season, which may be responsible for the disappearance of the limonic acid A‐ring lactone, the non‐bitter precursor of limonin. the nature of this process is not yet established, but there are indications that it is of an enzymic nature.
The effect of heat treatment on the β‐glucosidase activity in canned whole apricots
Authors: HERSHKOVITZ ESTHER , KANNER J.
Published: July 2010

Summary. Undesirable odour and flavour in canned whole apricots are caused by the products of the β‐glucosidase activity in the apricot kernels. the hydrocyanic acid content in canned apricots heat treated for 38 min at 86°C was found to be approximately 1 ppm, with no changes occurring even after long storage; the figure reached a maximum of 16–17 ppm after 150 days of storage at room temperature in fruit heat treated at the same temperature but for only 20 min.
Concentration processes for liquid foods containing volatile flavours and aromas
Authors: THIJSSEN H. A. C.
Published: July 2010

Three concentration processes are technically feasible for the selective dewatering of liquid food, viz. evaporation with aroma recovery, freeze concentration and reverse osmosis.

Concerning quality preservation the freeze concentration is superior to the other two processes. the process is not yet developed to full technical maturity, however. It seems likely that in the coming years it will deprive the established evaporation process of its monopoly position. Reverse osmosis has not yet passed the laboratory scale stage. Because membranes with acceptable permeabilities are not very selective, it can be expected that their technical application in dewatering aroma‐containing liquid foods will remain restricted to some specialties.

The costs of concentration are about the same for evaporation and freeze concentration. the higher investment costs of the latter process are partially offset by lower costs of energy. Depending upon the capacity and yearly operation hours the costs vary between ±5 and ±15 per ton water removal. Reverse osmosis may become competitive at more than 100 operation days per year.
Retention and release of volatile food flavour compounds
Authors: GRAY J. I. , ROBERTS D. G.
Published: July 2010

The retention and release of volatile flavour compounds such as aldehydes, ketones, alcohols, amines and sulphides from various substrates have been studied. Activation energies of desorption were measured using a thermal balance and heats of preferential sorption were measured with a flow microcalorimeter. Activation energies were obtained for the release of ethylamine from pectin, but insufficient amine was adsorbed to obtain values for Schardinger β‐dextrin, gelatin and sodium alginate.

All the flavour compounds studied gave detectable heats of preferential sorption with silica gel. of the other systems studied only triethylamine and ethylamine gave detectable heats of preferential sorption both with pectin and Schardinger β‐dextrin.
The connective tissues of fish III. the effect of pH on gaping in cod entering rigor mortis at different temperatures
Authors: LOVE R. M. , HAQ M. A.
Published: July 2010

When cod enter rigor mortis and are then filleted, the amount of gaping seen between the muscle segments depends on the previous body temperature, increasing progressively with warmth. In the present work it was noticed that in any batch of fish a few pairs of fillets showed little gaping even at relatively high temperatures (22‐25°C). the factor responsible was identified as the pH of the muscle, a low pH leading to much gaping and vice versa. At a given temperature, the gaping increased with time, and subsequent freezing increased it further. the practical implications of these findings are discussed.
The connective tissues of fish. IV. Gaping of cod muscle under various conditions of freezing, cold‐storage and thawing
Authors: LOVE R. M. , HAQ M. A.
Published: July 2010

The rate at which whole cod were frozen was shown to have little effect on the gaping of the fillets cut after thawing, though very slow freezing did cause a small increase. Cold storage at ‐ 14°C to produce varying degrees of muscle protein denaturation did not affect gaping, neither did the manner of thawing (four methods used). However, the experiments, involving hundreds of fish amply confirmed that gaping increases when the fish are frozen after entering rigor mortis (compared with pre‐rigor) and increases again if they are frozen after a longer time in melting ice.

Removing the skin before freezing the whole gutted fish was shown to reduce the gaping, presumably by reducing the tension on the myocommata. the greatest reduction was obtained with fish skinned in rigor mortis, where muscular tension is greatest.

Haddock always gaped more than whiting, although they are very similar related fish, and were selected to be of similar lengths. the present work showed that the ultimate pH of the two species was very different, that of haddock being lower. the difference in pH probably accounts for the difference in gaping, but the reason for the two species having such a disparity in pH is not known. It may relate to differences in intrinsic activity.
Automatic application of polyphosphate solution to fish fillets
Authors: WIGNALL J. , POTTER D. P. , WINDSOR M. L.
Published: July 2010

A pilot plant is described for the automatic polyphosphating of fish, the capacity being 570 kg per hour. the importance of volume control and maintenance of polyphosphate solution concentration is examined. Filtration and cooling systems fitted to the pilot plant are described. Data on changes in the solution, (concentration etc.), and changes in the fish, (weight changes, shelf‐life changes), are presented; these data were obtained under commercial conditions with high throughput of fish.
The use of sulphur dioxide during the production of brined cauliflower
Authors: DAKIN J. C. , SCHOLEY J.
Published: July 2010

The minimum level of sulphur dioxide necessary to maintain brined cauliflower in a good white condition and the stage in brining at which it is best added were determined. In a factorial experiment, samples of cauliflower were brined in 50° salinometer brine, with various sulphur dioxide contents (ranging from 50 to 1000 ppm overall) added at four different stages of brining. After 6 months storage the cauliflower was freshened and placed in acetic acid solution. the curds were ranked for whiteness at the completion of brining and after acidification. the texture of the stalk was measured with an Instron Universal Testing Rig, but no significant differences were found. Observed differences between samples were confined to the whiteness of the curd which progressively improved with increasing sulphite content to a constant level. It was concluded that, in relation to whiteness and residual sulphur dioxide, the optimum effect was produced when sulphur dioxide was added to the second brine and that 300 ppm overall was sufficient to retain the curd in a good white condition.
A quantitative investigation of Shallenberger's sweetness hypothesis
Authors: BIRCH G. G. , COWELL N. D. , EYTON D.
Published: July 2010

A method for assessing the validity of Shallenberger's sweetness hypothesis by measuring the sweetness of non‐reducing sugars is described. the stable, conformationally analogous compounds, α, α‐trehalose (mushroom sugar), and methyl α‐D‐glucopyranoside have the same sweetness on a molar basis. This indicates that only one of the glucose residues in the α, α‐trehalose molecule is involved in binding to the taste bud protein, and hence a real chemical basis exists for the phenomenon of sweetness.
Preference tests to compare the acceptability of several processed foods
Authors: HILL MARGARET A. , ARMSTRONG J. F. , GLEW G.
Published: July 2010

Preference tests were carried out on seven products, each of which had been processed in different ways. Precooked frozen, canned, dehydrated and freshly cooked products were investigated.

In general, the dehydrated products were the least acceptable and the precooked frozen and fresh products were given the highest score, except in the case of carrots, where the canned product received the highest score.

There was no significant difference between any of the precooked frozen and fresh products tested.
The keeping qualities of different grades of maize meal stored under different climatic conditions
Authors: TWISK P. VAN
Published: July 2010

The effects of prolonged storage on the quality of commercial maize meal were investigated. Maize meal was stored in atmospheres corresponding to climatic conditions prevailing in the more important ‘consumer areas’in South Africa. the storage stability of the three main grades of maize meal, viz. unsifted granulated, sifted granulated and special sifted granulated, which differ in fat and fibre contents, was investigated. Furthermore, the relative merits of polyethylene and cotton as packaging material were studied. It was found that evaluation by means of acidity number and peroxidase activity values yielded results which provided the best basis for predicting the level of acceptance (by sensory evaluation) at that time and after further storage. Peroxide values, thiobarbituric‐acid number and catalase activity could not be recommended as criteria for the evaluation of maize meal. It was found that all grades of maize meal, stored under relatively favourable climatic conditions, remained in edible condition for a longer period when packaged in cotton bags than when polyethylene was used. the reverse was found to be the case when ambient humidities were very high (75% or greater). the shelf life of maize meal decreased with increasing fat content, this effect being most significant at elevated temperatures and high humidities.
Foot‐and‐mouth disease, its relation to meat and meat processing
Authors: ROBERTS P. C. B.
Published: July 2010

The survival of foot‐and‐mouth disease virus (FMDV) in meat and meat products is briefly reviewed.

An evaluation of established food processes in relation to viral inactivation is presented, together with a discussion on the application of novel processes. the potential for basing process evaluation on a non‐restricted, but essentially similar virus, is also discussed.
The effect of muscle excision before the onset of rigor mortis on the palatability of beef
Authors: SCHMIDT G. R. , GILBERT K. V.
Published: July 2010

A study has been made to determine if organoleptically and microbiologically acceptable beef could be produced by pre‐rigor excision followed by rigor setting and short‐term aging of bovine muscle. Six carcasses (three steers, two young bulls and one old bull) were subjected to each of three treatments: (1) the control side of each carcass was chilled at 9°C for 24 hr; (2) one sample (PRE‐24) from each of five sites on the other side of each carcass was removed pre‐rigor and stored at 15°C for 24 hr; (3) one sample (PRE‐48) from each of five sites was stored at 15°C for 48 hr.

Although the PRE‐24 samples of the middle of the biceps femoris, anterior longissimus, and posterior longissimus were generally assessed to be similar to their controls in tenderness and other organoleptic properties a further 24 hr storage at 15°C resulted in a significant tenderization of the PRE‐48 samples from these locations relative to their controls (P < 0.05). There was no treatment effect on the semimembranosus, whereas the semitendinosus toughened after being excised pre‐rigor. Mean bacterial numbers were held within the range 102−105/cm2 muscle surface after 48 hr storage at 15°C in a sealed, gas‐impermeable bag.

The investigation shows that a procedure for the pre‐rigor excision of bovine muscle can produce organoleptically acceptable beef of a satisfactory microbiological standard.
Heat treatment of flour as an alternative to chlorination
Authors: RUSSO JUDITH V. , DOE C. A.
Published: July 2010

Experimental work leading to the discovery that heat treatment of air classified turbo ground flours to a temperature of 120°C produces flours with vastly improved high ratio sponge and cake baking properties is described. the starch in the heat treated flour is found to be resistant to swelling in DMSO solutions ‐ a fact which can be utilized to monitor the heat treatment process. the mechanism of the improving action is still obscure.
The bacteriology of ‘Scampi’(Nephrops norvegicus). I. Preliminary bacteriological, chemical and sensory studies
Authors: WALKER P. , CANN D. , SHEWAN J. M.
Published: July 2010

A bacteriological, chemical and sensory study has been made of iced and uniced scampi (Nephrops norvegicus) stored at an ambient temperature of 2.2°C. After 8–10 days storage, the scampi became inedible due to the presence of strong, ammoniacal, sour odours and flavours. the bacterial counts, of iced and un‐iced scampi, both of which were made at 20°C and 37°C, rose sharply after the fourth day reaching values of 106/g at 20°C and 104/g at 37°C at the end of the storage period. the initial bacterial flora, consisting mainly of coryneforms (80%), gradually changed during storage until it finally consisted mainly of Achromobacter species (70%). the total volatile base and trimethylamine content of the flesh also increased considerably during storage, reaching values of approximately 70 and 20 mg N/100 g flesh after 10–12 days; initial values were about 20 and 0.5 mg N/100 g flesh, respectively.
Analysis of the active principle in the biological insecticide Bacillus thuringiensis Berliner
Authors: BATESON J. B. , STAINSBY G.
Published: July 2010

A detailed analysis of the toxic principle of the biological insecticide, the crystals of B. thuringiensis, is given. Almost all (96.1%) of the nitrogen in the crystals, but only about 85% of the weight, is accounted for by amino acids. the imino acid, proline, is absent. A non‐nitrogenous fraction, accounting for 12% of the dry weight of the crystals, has been separated by dissolving the polypeptide part in dilute alkali. the non‐nitrogenous fraction is largely carbohydrate, and the crystals are probably composed of glycoprotein.

The insolubility of the crystals cannot be fully explained by reference solely to the amino acid composition, and it is suggested that the carbohydrate moiety makes a contribution to the insolubility.
Evaluation of electrolytic tinplates for juice containers
Authors: LANDAU M. , MANNHEIM C. H.
Published: July 2010

The corrosion resistance of three ordinary and two K‐type makes of tinplate was investigated, with grapefruit juice as test medium. Four criteria, namely the Alloy Tin Couple, Iron Solution, Pickle Lag Values, and dissolved tin after storage at 25° and 35°C, were used. K Plate proved significantly superior to ordinary plate with identical nominal coating weights but from different sources. the ATC test was found to compare best with dissolved‐tin values in a grapefruit juice test pack. It was also shown that this test is suitable for corrosivity evaluation of different media.

Electron‐microscopic examination showed a more continuous tin‐iron alloy layer, with smaller crystals, in the K Plate.
Analysis of pigments in intact beef samples: A simple method for the determination of oxymyoglobin and ferric myoglobin in intact beef samples using reflectance spectrophotometry
Authors: van den OORD A. H. A. , WESDORP J. J.
Published: July 2010

Some basic aspects of the determination of the relative proportions of myoglobin pigments in meat by reflectance spectrophotometry are briefly reviewed. The potential of the Unicam SP 890 diffuse reflectance accessory for the quantitative determination of myoglobin forms in beef is assessed. The construction of the Unicam apparatus differs from most other reflectance units in that it has no integration sphere. The K/S values obtained with the Unicam apparatus and the requirements to be met by the samples correlate well with those for other spectrophotometric apparatus, except that the thickness of meat samples does not seem to affect the measured reflectance.

A simple and rapid method is described for the determination by reflectance spectrophotometry of the proportion of oxymyoglobin and ferric myoglobin in meat surfaces. If only negligible amounts of reduced myoglobin are present in the sample, then the absorbance at 580 nm minus the absorbance at 630 nm is linearly related to the percentage of oxymyoglobin, or ferric myoglobin. The theoretical basis for this linear relationship is outlined. A drawback of the method is that the difference in absorbance (A580 ‐ A632) is dependent on the myoglobin concentration in the meat sample. Nevertheless, the method is very convenient for comparing the pigment composition of meat samples with similar myoglobin contents and for following the course of pigment changes in a single meat sample.
Colour rating and pigment composition of beef: Relation between colour measurement by reflectance spectrophotometry, subjective colour evaluation, and the relative concentration of oxymyoglobin and ferric myoglobin in chilled retail‐packed beef
Authors: van den OORD A. H. A. , WESDORP J. J.
Published: July 2010

Reflectance measurements and subjective colour evaluations of retail‐packed beef were recorded and compared. Subjective colour evaluation, which was found to be closely linked to the visual assessment of the overall quality of the meat, is largely determined by the percentage of oxymyoglobin (red) relative to ferric myoglobin (brown). The reflectance colour value, which is the difference in reflectances (expressed in absorbance units) at 580 and 630 nm, is linearly related to the percentage of oxymyoglobin and to the subjective colour score. The correlation between objective and subjective colour evaluation is statistically highly significant (correlation coefficient = 0.94).

Reflectance spectrophotometry is thus shown to be a convenient and reliable method for objective colour measurement and for the determination of the pigment composition in the surface zone of intact beef samples.
Application of the ‘D‐concept’to heat treatments involving curing salts
Authors: INGRAM M. , ROBERTS T. A.
Published: July 2010

Canned cured meats are as safe as uncured meats which have received a 12‐D heat process (‘botulinum‐cook’) after heat treatments approximately one‐fifth as great. Preliminary findings in laboratory media indicate that the D‐concept may be equally applicable to cured meats, with a correspondingly smaller value of D. A means of calculating the effect of curing salts is described and suggestions are made for further study.
Development of marinated herring
Authors: McLAY R. , PIRIE R.
Published: July 2010

A marinated herring has been produced which has a higher acceptability than some commercially produced packs. It has a storage life of at least 4 months in the first pickle and 3 months in the second pickle.
The threshold value for physiological action of ethylene on apple fruits
Authors: HARKETT P. J. , HULME A. C. , RHODES M. J. C. , WOOLTORTON L. S. C.
Published: July 2010

In fruit picked at various stages of development and stored at 12°C, the threshold concentration of applied ethylene required to cause an increase in respiration decreased as the fruit matured. In young fruits 10 days elapsed between the application of 10 ppm ethylene (for the first 3 days) and an increase in respiration. By contrast, in mature fruit, close to the respiration climacteric, as little as 0°1 to 1 ppm ethylene induced an increase in respiration within a few days. Relatively massive production of ethylene and the development, in discs of peel taken from the fruit, of a malate effect (excess CO2 produced on addition of malate) occur some time after increase in respiration. The implications of these results in the control of the respiration climacteric are discussed.
Protein quality and quantity: A rheological assessment of their relative importance in breadmaking
Authors: WEBB T. , HEAPS P. W. , COPPOCK J. B. M.
Published: July 2010

It is suggested that the terms ‘strong’and ‘weak’derived from bakery experience may not always be directly applicable to the quality of gluten present in such flours, and may be more related to gluten quantity than hitherto believed. It is clearly demonstrated in this work that the quality of glutens derived from ‘strong’and ‘weak’flours may be similar, although the glutens may be present in dissimilar quantity. There are, of course, certain flours which have poor glutens but until these are detected by precise rheological measurements, it is wrong to assume that the empirical rule ‘weak flour means poor gluten quality’holds true.
An accelerated system for screening of process variables and freshness indices of irradiated fishery products
Authors: ALUR M. D. , MADHAVAN V. N. , LEWIS N. F. , KUMTA U. S.
Published: July 2010

Incubation of fish homogenates at 30°C led to enhancement of microbial growth and other freshness indices like TMA and TVBN values enabling rapid screening of process variables. This accelerated test system was found to be successful when applied to shrimps and four species of locally available fish, viz. Indian Salmon (Eleutheronesma tetradactylum), Surmai (Scomberomorus gettatus), Pomfret (Stomateus cinereus) and Bombay duck (Harpodon nehereus); which were either untreated or subjected to gamma radiation with or without combination of sodium nitrite and benzoic acid.
A practical approach to water sorption isotherms and the basis for the determination of optimum moisture levels of dehydrated foods
Authors: CAURIE M.
Published: July 2010

The underlying principle for the determination of the optimum moisture content (Mo) for the stability of dehydrated foods and materials of different adsorption patterns is discussed. Sorptive forces have been suggested as playing a very important role in the determination of Mo values. The relation between Mo and heat of sorption has been established and graphically illustrated.

The effect of external conditions on the variation in sorptive as well as Mo values has been illustrated graphically. Alternative methods for the determination of Mo values have also been suggested.
Effects of oxygen diffusion on oxidation of some dry foods
Authors: QUAST DIETRICH , KAREL MARCUS
Published: July 2010

The rate of oxygen uptake and the effective diffusivity of oxygen in some porous food products were determined. The effect of oxygen diffusion on the overall rate of oxygen uptake was investigated in these foods and in other food products for which approximate values of oxidation rate constants and of oxygen diffusivity existed in the literature. The results show that diffusion can be a rate‐limiting factor under certain conditions of commercial processing and handling.
The softening of frozen meat: Criteria for transportation in insulated containers without refrigeration
Authors: HAUGHEY D. P. , MARER J. M.
Published: July 2010

Measurements of the effect of temperature on the softness of frozen meat and offal are described. The assessment of softness was made under controlled laboratory conditions, both with a load‐deflection penetrometer, and subjectively. The implications for meat quality are also discussed.

The results are used to determine criteria for the maximum allowable temperature for the various meat products at any point in the stow during transportation in an insulated container without refrigeration. It is shown that for frozen beef, lamb or mutton in either carcass, boneless or cut form, the appropriate limit is 25°F (– 4°C). For offals a limit of 23°F (– 5°C) is more satisfactory. These criteria were confirmed by container trials under practical operating conditions in New Zealand.
Influence of carcass cooling rate on drip loss in pigmeat
Authors: TAYLOR A. A. , DANT S. J.
Published: July 2010

Pig sides were cooled to 0°C at two different rates and the amount of drip from joints after storage for two days at 0°C was estimated. Drip accurred according to an anatomical distribution pattern which was unaffected by cooling rate and breed, the greatest loss being from the loin and leg joints. The quicker cooling rate consistently limited the amount of drip, regardless of breed. This was demonstrated using whole carcasses, leg joints and individual muscles. Pigs whose pH fell rapidly after slaughter tended to give joints with high drip loss but, even with these, the effect of quicker cooling was still observed.
The bacteriology of ‘scampi’(Nephrops Norvegicus:). II. Detailed investigation of the bacterial flora of freshly caught samples
Authors: CANN D. C. , HOBBS G. , WILSON BARBARA B. , HORSLEY R. W.
Published: July 2010

Forty‐nine samples of freshly landed Nephrops norvegicus, from thirteen ports of landing, were examined bacteriologically. Total viable counts ranged from 3.55 × 103/g—2.25 × 106/g at 20°C and 3 × 101/g—2.73 × 106/g at 37°C. Coryneform organisms were predominant in the bacterial flora with strains of the Achromobacter‐Acinetobacter group and the Pseudomonas, Cytophaga and Micrococcus genera also present.
Some laboratory experiments on various meat preparation surfaces with regard to surface contamination and cleaning
Authors: GILBERT R. J. , WATSON HEATHER M.
Published: July 2010

Laboratory experiments have been carried out to determine the bacterial plate counts on various meat preparation surfaces both before and after cleaning. The surfaces tested included wood, five proprietary cutting boards and formica. Experiments on both unused and scored surfaces showed that plate counts from wood were always greater than those from all the other boards tested indicating that the latter can be cleaned more efficiently.

Tests were made to determine the incidence of salmonellae on wooden surfaces in frequent contact with raw meat. Ten (4.3%) of 235 samples of wood scrapings were found to contain salmonellae. These results confirm that wooden surfaces can be reservoirs and distributors of salmonellae.
A semi‐quantitative procedure for detecting Clostridium welchii in foodstuffs
Authors: LOWIS M. J.
Published: July 2010

The role of Clostridium welchii in food poisoning is well documented. A procedure for detecting these organisms is described and this consisted of (a) making inoculations or sample dilution into cooked meat medium, (b) subculturing to sulphite agar, (c) transferring black colonies to Nagler medium, and (d) Gram‐staining growth from positive reactions. All media contained polymyxin and were incubated at 44°C. Experiments showed that the method would detect a mean of approximately 0–8 Cl. welchii organisms on one of three occasions and approximately eight organisms on at least two of three occasions. This was more sensitive, although slower than with similar experiments using litmus milk.
The measurement of tin in canned beans by atomic absorption spectrophotometry
Authors: CAMERON A. G. , BRITTAIN J. E.
Published: July 2010

The atomic absorption technique for the measurement of small amounts of tin offers advantages of speed, simplicity and freedom from interferences compared with colorimetric procedures, provided that rapid sample preparation can be achieved. Rapid methods of sample preparation for canned beans, one using concentrated hydrochloric acid and the other concentrated sulphuric acid, are described and shown to be reliable. The hydrochloric acid digestion technique coupled with atomic absorption measurements is shown to give comparable results to the catechol violet colorimetric procedure and to be both quicker and simpler to perform.
A single layer moisture absorption theory as a basis for the stability and availability of moisture in dehydrated foods
Authors: CAURIE M.
Published: July 2010

It has been shown that moisture absorption in dehydrated foods cannot form a layer more than a single molecule deep and the stability of the food has been shown to depend on this single layer. The use of an Aw scale as an index of available moisture in dehydrated foods has been shown to overestimate the parameter. Suggested new definitions have been expressed directly as percent moisture and as a ratio of the total moisture/bond energy or gaseous water content. It has also been shown that the laboratory method of dehydrating materials at constant temperature by lowering the ambient humidity may impair the subsequent absorption capacity of the material if the humidity is lowered below a certain critical minimum value.
The control and evaluation of spoilage *
Authors: DAINTY R. H.
Published: July 2010

Methods currently used in the control and evaluation of spoilage of meat are reviewed and their value discussed. In many instances scientific explanations of the effectiveness of the control methods are lacking, e.g. the mechanism of action of carbon dioxide or sodium nitrite in controlling microbial growth. A lack of knowledge regarding the chemical and biochemical processes involved in spoilage hinders the development of completely satisfactory methods of spoilage evaluation. Research directed towards rectifying this could lead to the development of new and perhaps more effective methods of spoilage evaluation and control.
The bacteriology of ‘scampi’(Nephrops norvegicus). III. Effects of processing
Authors: HOBBS G. , CANN D. C. , WILSON, BARBARA B. , HORSLEY R. W.
Published: July 2010

The effects of handling and processing on the bacteriology of Nephropsnorvegicus has been examined in five processing factories. Production of frozen ‘scampi’and frozen breaded scampi were examined along with, in one case, the bacteriological aspects of automated polyphosphate treatment.

Apart from some contamination during hand peeling, there was no significant increase or decrease in the numbers of any of the various types of bacteria during processing. Studies of the spoilage flora developing during ice storage show that, in common with other fishery products, bacteria of the Pseudomonas‐Achromobacter group predominate.
Studies on the quality characteristics of canned grapefruit segments. III. Addition of surfactant agents during the lye‐peeling process to improve their quality *
Authors: LEVI A. , HERSHKOWITZ ESTHER , LUDIN A.
Published: July 2010

Lye peeling of grapefruit segments greatly facilitates the removal of the carpellary membranes, but causes a decrease in the yield and quality of the whole peeled segments. The HC1 treatment used in some industrial plants not only does not improve the quality, but usually causes a decrease in the yield or in the quality. The use of ‘wetting’agents, such as Faspeel and Tergitol, helps to reduce the temperature or concentration of the lye solution, thereby bringing about an increase in yield and an improvement in the canned segments’quality.
The examination of starch gelling by microscopy
Authors: FREKE C. D.
Published: July 2010

A microscopic method of determining the gelling temperature of starches has been developed. The apparatus is described and some results showing the effects of varying concentrations of sucrose at two pH values on two starches are presented.
Protein, lactose and lactic acid separation from cheese whey using reverse osmosis dynamically formed membrane
Authors: FREEDMAN A. M. , SHABAN H. I.
Published: July 2010

Hydrous zirconium oxide dynamically formed membrane was used in reverse osmosis apparatus to separate protein, lactose and lactic acid from cheese whey directly. An unexpected feature was 40% rejection of pure protein within 1°1/2 hr from commencement of experiment. However, protein rejection figure changed to 44% with undesirable 17°4% lactose rejection and 29% lactic acid rejection after 4 hr approximately. The permeation rate of solvent across the membrane was constant and the colour rejection of cheese whey was almost complete (approx. 100%).
Measurement of oxygen penetration into meat using an oxygen micro‐electrode
Authors: MORLEY M. J.
Published: July 2010

An oxygen microelectrode was applied to the measurement of the penetration of oxygen into lean meat exposed to the air. The variation of oxygen penetration with time, temperature and muscle type was investigated. Results show that penetration increases fairly linearly with time, until heavy surface contamination occurs. Fairly large variations were observed between different muscles. The results were compared with related colour and muscle‐respiration data.