bluuebunny/crossref_metadata_2025 huggingface dataset:
Degradation of sorbic acid in fruit squashes and fish paste
Authors: VIDYASAGAR K. , ARYA S. S.
Published: July 2010

Degradation of sorbic acid (SA) in fruit squashes and fish paste has been found to be influenced by the nature of the food material and the packaging system. Losses in SA ranged from 60–90% in polypropylene and 41–65% in saran coated cellopoly pouches to 22–30% in paper‐aluminium foil‐polyethylene laminate pouches and glass bottles after 150–210 days at 37°C. The rate of degradation was significantly higher in fish paste than in fruit squashes.

The major portion of the added SO, in fruit squashes was lost during the initial stages of storage and the residual SO, (< 100 ppm) did not significantly influence the rate of degradation of SA. Browning intensity in fruit squashes and fish paste was also related to the oxygen permeability of the packaging materials. Addition of 0.1 % SA did not significantly influence the rate of browning but at 0.2%, a slight increase in the rate was observed.
Role of carbohydrates in soya extrusion
Authors: SHEARD P. R. , LEDWARD D. A. , MITCHELL J. R.
Published: July 2010

When extruded under similar processing conditions, soya flour yielded a far more regular, honeycombed structure than soya isolate, though both had similar expansion ratios. At low concentrations both extrudates were almost totally soluble in solutions containing sodium dodecyl sulphate (SDS) plus 2‐mercaptoethanol (ME), although in SDS or ME the extrudates were only partially soluble. These results suggest that, in both cases, the extrudates are primarily stabilized by disulphide bonds and hydrophobic interactions.

When rehydrated in water at temperatures in the range 20–120°C all the extrudates exhibited decreasing toughness and increasing protein solubility with increasing temperature. Also, the soya flour extrudates, but not those prepared from the isolate, exhibited a phenomenon at the lower temperatures characterized by minimum hydratability, pH and carbohydrate solubility at about 30–40°C. It is suggested that the soya flour extrudates are additionally stabilized, compared to the extrudates prepared from the isolate, by hydrophobic interactions involving the embedded carbohydrate.
Note on the economics of batch freeze dryers
Authors: MILLMAN M. J. , LIAPIS A. I. , MARCHELLO J. M.
Published: July 2010

An economic analysis of various operational policies associated with a batch freeze dryer is presented. Skim milk is used as a model material. It is shown that the lowest cost of production corresponds to the highest production rate. This occurs when large sample thicknesses are used, the chamber pressure is at its lowest value and the upper and lower heating plates are independently controlled such that the melting and scorch constraints are both encountered and held during the free water removal phase. Therefore, the operational regime that provides the shortest drying times during the free water removal phase (Millman, Liapis & Marchello, 1984, 1985) will also provide the smallest production costs and highest capacities.
Increase on free fatty acids during ripening of anchovies (Engraulis anchoíta)
Authors: ROLDAN H. A. , BARASSI C. A. , TRUCCO R. E.
Published: July 2010

The changes of free fatty acids (FFA) during the ripening of salted anchovy was studied. In the course of the curing process, the content of free fatty acids (FFA) in the muscle increased fifteen‐fold, mostly in the first 100 days of the process. Each sample was subjected to sensory evaluations. A high correlation between FFA contents and sensory scores was found. Therefore the determination of FFA is proposed as an objective index to assess the ripening of salted anchovies.
Effects of different types of carrageenans and carboxymethyl celluloses on the stability of frozen stored minced fillets of cod
Authors: PONTE D. J. B. DA , HERFST J. M. , ROOZEN J. P. , PILNIK W.
Published: July 2010

Different types of carrageenans and carboxymethyl celluloses were used as additives (5 g/kg) for minced fillets of cod. Samples of these treatments were stored at −18°C for 10 weeks and were evaluated at regular intervals for pH, water holding capacity, texture, extractable myosin and formation of dimethylamine and formaldehyde.

Except Kappa carrageenan the additions improved the water holding capacity of the raw and cooked minced fish and decreased toughening during frozen storage. The addition of Iota carrageenan resulted in samples with remarkable texture stability and so after 10 weeks of frozen storage the texture of this treatment was similar to fresh minced cod. The higher the viscosity of carboxymethyl cellulose, the more it increased the softness and water holding capacity.
Compositional differences of black, green and white pepper (Piper nigrum L.) oil from three cultivars
Authors: BUCKLE K. A. , RATHNAWATHIE M. , BROPHY J. J.
Published: July 2010

The composition of volatile oil from black, green and white pepper products of a local Sri Lankan cultivar has been compared with that for the Panniyur and Kuching cultivars introduced from India and Sarawak respectively. The Local Sri Lankan cultivar is rich in P‐caryophyllene, a major proportion in sesquiterpene hydrocarbons, and is more suitable for the perfumery industry than are the other two cultivars. The high proportion of oxygenated compounds in the Panniyur cultivar makes an important contribution to the overall odour quality of its pepper oil while the Kuching cultivar, containing a higher monoterpene concentration with a significant content of pinenes, is rich in the top peppery notes. Knowledge of the variation in the composition of pepper oils from different cultivars is important when pepper is used as a component of food flavourings.
Studies of the iced storage characteristics and composition of a variety of Bolivian freshwater fish. 2. Parana and Amazon Basins fish
Authors: POULTER N. H. , NICOLAIDES LINDA
Published: July 2010

A selection of fish from the warm lowland waters of the Parana and Amazonian Basins were studied to determine their shelf lives and spoilage characteristics when stored in crushed ice. The proximate composition and physical nature of these fish species was also determined. A shelf life of 25 days was estimated for sabalo (Prochilodusplatensis) from the Parana Basin regardless of whether the fish were stored entire or eviscerated. The larger fish from the Amazonian Basin, pacu (Colossoma macropomurn), chincuiiia (Pseudoplatystoma tigrinum) and tambaqui (Colossoma branchypomum) exhibited shelf lives of greater than 40 days. The smaller fish from this location had shelf lives of over 30 days for corvina (Plagioscion squamosissimus) and 25 days for bagrk (Ageneiosus spp.). An evaluation of the methods used to assess fish quality was made. The assertion that tropical fish have longer shelf lives than temperate species when stored in crushed ice is discussed.
Anthocyanin colourants from elderberry (Sambucus nigra L.). 2. Process considerations for production of a freeze dried product
Authors: BRØNNUM‐HANSEN Kirsten , FLINK J. M.
Published: July 2010

Freeze drying of elderberry anthocyanin extract under the proper conditions produces an intensely coloured powder with retention of both anthocyanins and physical structure. The various conditions examined included extract concentration, stabilizer concentration, pH and freeze drying conditions. It was found that minimum antho‐cyanin degradation and product structure alteration occur, when the undiluted extract is adjusted to pH = 3, has DE 20 maltodextrin structure stabilizer added to a 2.5% level and is freeze dried at a maximum platen temperature of 75â°C and maximum product temperature of 60â°C. Under these conditions, the recovery of anthocyanin is 94% and physical structure and solubility is preserved.
Selenium losses on cooking Greek foods
Authors: BRATAKOS M. S. , ZAFIROPOULOS T. F. , SISKOS P. A. , IOANNOU P. V.
Published: July 2010

The effect of various cooking practices (frying, grilling, boiling and canning) on the selenium content of selected food items has been determined. All foods examined upon cooking lost selenium and, in general, the harsher the cooking conditions the more selenium was lost. Fish lost 36–46%, meats 13–41%, cereals 20–30%, vegetables 12–37%, pulses and cereal products 5–10% selenium. It is estimated that Greeks receive 110 and c. 95 μg Se/day based on raw, and cooked plus uncooked foods, respectively. Cooking does not make a large difference to the daily selenium intake of Greeks because of their large consumption of bread.
A model for the hot water decontamination of sides of beef in a novel cabinet based on laboratory data
Authors: DAVEY K. R.
Published: July 2010

A predictive model for the hot water decontamination of sides of beef in a novel design of cabinet is presented and its usefulness illustrated. The model is based on laboratory data and permits assessment of bacterial reductions, production rates, unit energy costs and changes to cabinet dimensions and ambient temperatures. The advantages of a ‘standard’ cabinet recommended for a wide range of abattoir production rates are outlined. For a production rate of 135 sides h−1, 90% and 99% reductions in bacteria at the site of minimum treatment (the neck) could be achieved at costs of less than 0.016% and 0.03% respectively of the value of the meat. The model assumes limited exposure of the sides to the hot water to prevent a permanent impairment of meat bloom. A graphical summary is presented and limitations of the model are discussed.
Rheological behaviour of wheat flour dough in twin‐screw extrusion cooking
Authors: WANG S. M. , BOUVIER J. M. , GELUS M.
Published: July 2010

A capillary‐type viscometer was designed to measure the apparent viscosity of the cooked wheat flour dough on ‐line in a twin‐screw extruder. The effect of mean residence time and specific energy were studied in the ranges 20–45s and 300–800 kJ kkg−1, respectively. A viscosity model was developed which accounts for effects of wall shear rate, moisture content and specific energy. It was shown that the extent of the cooking reaction is largely determined by the specific energy applied.
Lethality calculation for thermal processes with different heating and cooling rates
Authors: PHAM Q. T.
Published: July 2010

In many thermal processes, the time constants fh and fc for the heating and cooling periods differ. This can cause difficulties in calculating the process lethality. This paper presents a simple method for taking into account this change in the time constant. The author's formula method is tested against simulated data from finite‐difference computations, both for fh=fc and for fh≠fc, and found to be at least as accurate as the best previous formula method.
Detoxification of cassava during gari preparation
Authors: VASCONCELOS A. T. , TWIDDY D. R. , WESTBY A. , REILLY P. J. A.
Published: July 2010

Gari, a fermented cassava product, is widely consumed in many West African countries. The present study was undertaken to investigate the detoxification of cassava during the preparation of gari. The most important processing stages, with regard to elimination of cyanide, were the initial grating of the cassava and the final roasting of the product. The breakdown of linamarin was dependent primarily on the presence of endogenous linamarase and the lactic acid bacteria present during the fermentation were not directly involved in its hydrolysis.
Acceptability of crackers (‘Keropok’) with fish protein hydrolysate
Authors: YU S. Y. , TAN L. K.
Published: July 2010

Proteins from Oreochromis mossambicus, a freshwater fish, were hydrolysed, using alkalase 0.61, to produce a soluble, spray‐dried hydrolysate. The hydrolysis was carried out at 50°C, using a ratio of one part water and one part fish mince, an enzyme:substrate ratio of 1:50 at pH 8.0. Reaction was terminated by heating to 90°C for 20min. After neutralization, the soluble fraction obtained after centrifugation was spray dried in a mini spray‐drier, at an air inlet temperature of 170°C and a feed rate of 41−1. The spray‐dried hydrolysate was incorporated into crackers which are fried before eating. Ten per cent hydrolysate was found to give maximum linear expansion. Sensory evaluation with 20 experienced assessors showed that in terms of appearance, crispiness and colour, crackers with hydrolysate had the highest scores, compared to crackers made with O. mossambicus and Sciaena sp. (Jewfish). There were no significant differences in overall acceptability in all three samples. Crackers with hydrolysate also had the highest nitrogen content.
The sensory quality of foods produced by conventional and enhanced cook‐chill methods
Authors: MASON L. H. , CHURCH I. J. , LEDWARD D. A. , PARSONS A. L.
Published: July 2010

Cook‐chill systems are now widely used within the catering industry. The basic method has been enhanced by the use of vacuum packaging to extend shelf‐life; and, it is claimed, sensory quality. This paper reviews the literature available on the sensory quality of foods produced by conventional and enhanced cook‐chill methods. It shows that the sensory quality of foods produced by these methods has received little attention from researchers, despite, in the case of methods using vacuum packaging, some extravagant claims about improved eating quality. Most attention has been paid to meat products. Deteriorative changes are shown to occur rapidly, but many variables affect the end result, which is often product and process specific. Lack of standardization, both in the catering industry and in experimental methods, makes comparisons between studies difficult.
Microbiological and physicochemical changes in minced meats under carbon dioxide, nitrogen or air at 3°C
Authors: NYCHAS G. J. , ARKOUDELOS J. S.
Published: July 2010

Microbiological changes were studied in minced beef and minced dark, firm, dry (DFD) pork stored under different atmospheres (100% in carbon dioxide, nitrogen or air) at 3°C. The storage life (time for 100‐fold increase in TVC) of samples flushed with carbon dioxide was increased by c. 3–4 days. Pseudomonads were the dominant organisms in samples stored in air, and lactic acid bacteria and Brochothrix thermosphacta in those stored under carbon dioxide. There was an alkaline drift in all samples, but at different rates (air > nitrogen > carbon dioxide). The rate of glucose assimilation in normal and DFD beef was slower in the samples stored under carbon dioxide than those under nitrogen or air. Lactate, gluconate, acetic acid, ethanol and diacetyl occurred in normal and DFD beef regardless of the storage atmospheres.
Desorption isotherms of shelled maize: whole, dehulled and hulls
Authors: TOLABA M. P. , SUAREZ C.
Published: July 2010

Water vapour desorption isotherms of whole kernel maize were determined at 40, 50 and 60°C, and those of dehulled kernels and hulls at 50 and 60°C. It was found that while whole and dehulled kernels show similar equilibrium moisture contents, the hull gives lower values. Equilibrium data were modelled with two‐parameter equations. It was found that the Henderson equation is best for describing the equilibrium data for whole kernels, while the Halsey equation was more appropriate for hulls. A simple semi‐theoretical equation was used to model the effect of temperature on the equilibrium values of whole maize kernels for the three temperatures investigated. BET heats of desorption and the isosteric heat curves were calculated for whole kernels and hull. It was found that the BET heat values correlate quite well with the isosteric heat values at the monolayer moisture content.
Fibre‐optic spectrophotometry for predicting lipid content, pH and processing loss of comminuted meat slurry
Authors: SWATLAND H. J. , BARBUT S.
Published: July 2010

A fibre‐optic light guide was used to measure the internal reflectance (interactance from 400 to 1000nm) of slurries of comminuted meat. For mixtures of pork adipose tissue and beef muscle with a low connective tissue content, internal reflectance at 1000nm was correlated with lipid content (r=0.99, P<0.005) and with cooking loss (r=0.99, P<0.005), and at 930nm with centrifugation fluid loss (r=0.77, P<0.005). For pork muscle varying in pH but adjusted to a constant lipid content, internal reflectance at 780nm was correlated with pH (r= ‐0.80, P<0.01), at 690nm with centrifugation fluid loss (r=0.74, P<0.025) and at 710nm with cooking loss (r=0.63, P<0.05). The additive nature of these correlations favours the use of internal reflectance to predict the functional properties of meat slurries.
Effective of component configuration and packaging materials on microwave reheating a frozen three‐componment meal
Authors: BOWS J. R. , RICHARDSON P. S.
Published: July 2010

The effects of food component layout and packaging materials (foil vs. plastic) on the microwave reheating characteristics of a standard experimental frozen ready meal consisting of ground beef (130g), processed peas (80g) and mashed potato (102g) were studied.

The results show that foil trays can be used successfully to achieve even heating, and that for best results the heating rates of the components need to be matched. This can be achieved by shielding the beef, so reducing the heating rate of the beef to that of the two vegetable components. The thawing times, heating rates after thawing and heating times to 72°C were used to quantitatively assess the effect of varying the component configuration and packaging material.

Heating times to 72°C ranged from 8.1 to 18.0min for the meals in the foil trays, and 6.0 to 12.5 min for the meals in the plastic trays. The mean heating rate after the thawing phase, of the meals in foil trays was 49.8°C min−1 and 65.5°C min−1 for the meals in the plastic trays.
Portable, low‐cost equipment for small‐scale fruit juice processing
Authors: CRANDALL P. G. , UPADHYAYA J. K. , DAVIS K. C.
Published: July 2010

Simple, low‐cost portable equipment to extract citrus juice, and pasteurize it and other fruit juices by passing through a coil of stainless steel tube in boiling water was designed, constructed and tested. Temperature reached was varied by altering the hydrostatic feed height, and the product was directly hot‐bottled and capped. Pasteurization was microbiologically effective, and had little effect on ascorbic acid, furfural and colour of freshly prepared pineapple orange, Valencia orange and apple juices, and an orange squash drink, and only the expected changes occurred on storage at 21°C for periods up to 6 months, although with no indication of microbial activity. Taste panel ratings showed a loss of liking for treated orange juice, but not for apple. The equipment is suitable for improved utilization of crops by community technology in less‐developed areas.
Colour stability of thawed lamb chops. II. Chops from loins frozen for long periods
Authors: MOORE V. J.
Published: July 2010

Colour stability was examined during simulated retail display of thawed chops cut from loins after frozen storage. When loins had been stored for 30 weeks at –20°C, the thawed chops had a 2‐day display life. If chops were stored at –20°C for an additional 8 weeks before thawing, display life decreased to 1 day. When loins were thawed, then cut into chops, a display life of 4 days was obtained. Thawed chops from loins stored for 60 weeks behaved similarly. The experiment showed no adverse trend with increased frozen storage, except for increased drip, and indicates definite commercial possibilities for chops cut from loins stored frozen.
Prediction and measurement of pasta quality
Authors: COLE M. E.
Published: July 2010

In the past several years, pasta and noodle products have become a major growth segment of the cereal foods industry. The popularity of pasta can be attributed to its sensory appeal, versatility, low cost, ease of preparation, strong nutritional image and excellent storage stability as well as to increased consumer interest in ethnic foods. Predominant quality attributes of pasta, as they relate to its appearance, flavour and texture, have been described in this review. Because of their importance to consumer acceptance, textural properties of pasta and noodles have been investigated most extensively. Commonly applied sensory, instrumental and chemical methodologies for prediction or measurement of these characteristics have been critiqued, and pitfalls of current approaches have been delineated. Although sensory appraisal has often been used to evaluate pasta quality, increasing reliance on physical and chemical measurements to provide estimates of product quality has been occurring recently in research laboratories.
Role of sorbic acid in nonenzymic browning reactions in liquid and solid model food systems
Authors: THAKUR B. R. , ARYA S. S.
Published: July 2010

Role of sorbic acid (SA) in browning development in model systems has been studied. In liquid model systems containing water‐glycerol‐glucose (WGG), water‐glycerol‐sucrose (WGS), 45% sucrose and 30% sucrose plus 15% glucose, SA degraded when stored at 37°C forming brown pigments. Addition of amino acids (glycine or lysine monohydrochloride) increased the rate of browning development while Cu2+ reduced SA degradation and browning development. In the absence of amino acids and SA, WGG and WGS systems did not brown appreciably.

In solid systems with SA adsorbed on microcrystalline cellulose, the maximum rate of browning occurred at 0.73aw, but maximum rate of SA loss was at 1.0aw. In all systems inclusion of amino acids reduced SA degradation but increased browning development. The rate of SA‐induced browning was considerably higher than that caused by sugar‐amino acid interactions.
Increased supercooling in irradiated foods
Authors: NESVADBA P.
Published: July 2010

The supercooling temperatures of γ‐irradiated and control cod, mushroom, and two chicken samples were measured using a Differential Scanning Calorimeter (DSC). The mean supercooling temperatures were significantly lower in three out of the four samples of the irradiated foods, suggesting that the effect might be the result of irradiation. There was high variability between samples and a possible dependence on spoilage which require further investigation to assess the potential of the test for detecting irradiated foods.
Loss of urea from the flesh of ray (Raja radiata) during the canning process
Authors: PASTORIZA LAURA , SAMPEDRO G.
Published: July 2010

Elasmobranch fish are under‐utilized as food because the high urea content produces unpleasant odours and flavours on storage and cooking. Cooking frozen ray (Raja radiata) in water or in steam, followed by canning in brine reduced the urea content of the muscle 4–5‐fold. This should reduce off‐flavour and thus improve utilization of ray as a canned product.
Limitations to modified atmosphere packaging for extending the shelf‐life of partly ripened Doyenné du Comice pears
Authors: GEESON J. D. , GENGE PIA M. , SHARPLES R. O. , SMITH S. M.
Published: July 2010

Although some retardation in ripening of Doyenne du Comice pears can be obtained when unripe fruit are held in modified atmosphere packs (MA) at 20°C, softening proceeds at a faster rate than chlorophyll loss so that the appearance of the fruit fails to match its internal condition. However, a 4‐day extension in shelf‐life was obtained by packing the fruit in a part‐ripe condition and, although the effects on rate of softening were less than those seen for unripe fruit, the yellower ground colour was more consistent with the eating qualities of the fruit. Increases in fruit‐to‐fruit variability, and in the risk of skin injury as the pears ripen in MA packs which were also recorded, are likely to preclude the commercial adoption of this technique for Comice pears.
Isoprotein composition and cross‐linking of thaumatins using mushroom tyrosinase and dimethyl suberimidate
Authors: RAMSOHOYE PAMELA V. , KOZLOV I. A.
Published: July 2010

Analysis of commercial thaumatin has now provided some evidence for more than the six known isoproteins by further resolution of thaumatins 0 and II. Purified isolates of thaumatins I and II were modified by mushroom tyrosinase and dimethyl suberimidate, creating cross‐linked thaumatin oligomers. The dimer (Mr 44400–44600) from the tyrosinase reaction still retained some sweetness, but the other did not. This dimer is one of the largest molecules so far observed as having a sweet taste.
Microbial development during tempeh fermentation from various beans and effect of Lactobacillus plantarum on the natural microflora
Authors: ASHENAFI M. , BUSSE M.
Published: July 2010

The microbial development during the fermentation of tempeh made of unacidified and acidified horsebean, pea, chickpea and soybean was studied. Increase in microbial count was observed during the fermentation of the various beans. Bacillus spp. and coryneform bacteria dominated the microflora of unacidified, and streptococci of acidified horsebean tempeh. In pea tempeh, lactobacilli dominated, in chickpea, micrococci, staphylococci and coryneform bacteria and in soybean tempeh, enterococci were the dominant genera. Inoculation of the cooked beans with Lactobacillus plantarum resulted in a lower pH and lower total counts in the various products. The use of Lb. plantarum in tempeh production may control the proliferation of undesirable microorganisms.
Modelling of a series of continuously stirred tank reactors for thermal processing of liquid foods
Authors: MALCATA F. XAVIER
Published: July 2010

A series of stirred tanks for the thermal treatment of liquid foods is easy to model and operate. Good modelling leads to accurate predictions and small uncertainties in the lethality, giving a safe food product because of a small chance of underprocessing. Mathematical proof is presented that the minimum overall reactor volume for a given degree of thermal destruction of cells or spores is obtained when the stirred tanks are of equal size. Analytical techniques based on theoretical residence time distributions are employed to find the optimum number of tanks in the series using capital and operation costs in the definition of the objective function. If typical scaling factors are used, these optima depend only on the degree of reduction of viable cells/spores sought and a dimensionless economic parameter relating operating and capital costs if a single stirred tank were employed.
Hydrostatic pressures in wet grinding of soybean with a double‐disk attrition mill
Authors: FURUTA S. , HAYAKAWA I. , FUJIO Y.
Published: July 2010

Soybean was finely ground with a modified double‐disk attrition mill by a wet‐grinding process. The hydrostatic pressure in the gap between the rotating and stationary disks of the mill decreased with radial distance between the central inlet and the peripheral exit in the disks. Observed values were in good agreement with theoretical values derived from Bernoulli's equation. The maximum hydrostatic pressure was found at the feed entrance zone of the gap under any given operational conditions. The effects of rotational speed, gap width and soybean feed concentration on the hydrostatic pressure were measured. This implied that increase in hydrostatic pressure from height of feed head and/or increased speed will increase output.
Adsorption isotherms of gari for estimation of packaged shelf‐life
Authors: CHUZEL G. , ZAKHIA N.
Published: July 2010

Adsorption isotherms of gari (eassava semolina) were determined at 15, 25 and 35°C, and the Guggenheim, Anderson and de Boer (GAB) isotherm model was applied to the data. At high water activities, the moisture content increased with rise in temperature, resulting in crossing of the isotherms at aw between 0.5 and 0.7. This sorption phenomenon can be explained by changes occurring in the starch structure and modifying the availability of water adsorption sites. Estimated shelf‐lives of gari are calculated and recommendations for its packaging and storage conditions are given.
Effect of dose rate and length of storage on the ESR signal strength in irradiated chicken bone
Authors: GRAY R. , STEVENSON M. HILARY
Published: July 2010

One hundred and twenty‐five pairs of chicken drumsticks were randomly allocated to one of five dose rates: 5, 10, 15, 20 or 600 kGyh‐. The highest dose rate was obtained using a linear accelerator whilst the remaining dose rates were provided using a 60Co gamma source. Each batch of 25 pairs was further divided into groups five of which were stored at 4°C for 0, 7, 14, 21 or 28 days. ESR spectroscopy was used to measure the intensity of the radiation‐induced signal. There was a quadratic relationship between ESR signal strength and dose rate, which although statistically significant is unlikely to be of practical importance. The magnitude of the ESR signal declined by about 20% over the first 14 days of storage at 4°C and thereafter the decrease was minimal.
Theoretical design analysis for a new instrument for the measurement of lean content of cartoned boneless meats
Authors: DAVEY K. R.
Published: July 2010

The theory for a new instrument for the on‐line (batch continuous), and in situ measurement of the per cent chemical lean content (CL) of whole cartons of boxed, boneless meats is outlined. This idealized instrument should be non‐invasive of the carton and non‐destructive of its meat content. A practical predictive model for CL is presented, based on a proposed novel method of meat volume determination and the established difference in density of the two components of meat, lean (i.e. fat free) and fat. The importance of simplifying assumptions and potential practical realization are discussed. Other potential applications to two‐component systems are briefly discussed.
Studies on the recovery of proteinaceous substances from chicken heads. I. An application of neutrase to the production of protein hydrolysate
Authors: SURÓWKA KRZYSZTOF , FIK M.
Published: July 2010

Minced heads of broiler chickens were hydrolysed under various conditions using neutral protease from Bacillus subtilis. It was found that hydrolysis goes at an optimum rate at 55°C and pH 7. Addition of 75% of water and 0.2% of the enzyme (w/w) to the hydrolysed raw material was sufficient to obtain a good hydrolysis yield. After 6 h of proteolysis, 1 kg of the raw material yielded 75 g of dry hydrolysate with 78.1% total protein content (N x 6.25). The nitrogen yield from this raw material amounted to 39.6%. The final product was brown coloured, of good microbiological quality, had no bitter taste and contained a number of mineral compounds. It also revealed good solubility in water but had relatively poor emulsifying properties. It was shown that nutritional quality of the product is limited by sulphur amino acids.
Importance of redfeed level, fish size and roe content to the quality of roe capelin
Authors: BOTTA J. R. , KENNEDY K. M. , KICENIUK J. W. , LEGROW J.
Published: July 2010

The importance of various levels of redfeed, fish size, roe content, and length of storage at dockside while frozen, and during and after thawing, to the incidence of autolysis of the exterior of the visceral cavity of roe capelin were examined. Evaluations of 106,860 roe‐capelin revealed that redfeed level, fish size, and roe content had little effect. The most important factors were frozen storage time and thawing time, followed by length of dockside storage. It was found that this aspect of the quality of roe‐capelin could best be improved by reducing the times and temperatures to which roe‐capelin are exposed prior to freezing, during frozen storage, and during and after thawing.
Seasonal variation in the calibration of a microwave fat: water content meter for fish flesh
Authors: KENT MICHAEL , LEES ALEXANDER , CHRISTIE ROBERT H.
Published: July 2010

A microwave fat: water content meter designed for use on pelagic fish has been found to exhibit seasonal changes in calibration. This has been examined in detail for sprats (Sprattus sprattus) and herring (Clupea harengus) and is ascribed in part to the seasonal changes in these species of the protein content, which influences the rotational mobility of water in the tissue. Various solutions to the problems are proposed.
Mutagenicity of N‐nitroso compounds in Chilean ham and sausages
Authors: ARANDA MARCELA , TRIVINO IVAN , OSORIO ANGELICA , BASTIAS JOSE M. , ROOS ORIETA
Published: July 2010

Chilean hams and sausages were analysed for the presence of nitrosodimethylamine and nitrosodiethylamine by GLC/NPD. The presence of 3.5–210ppb levels were found in 51.6% of the samples. All of the positive samples contained nitrosodimethylamine while only 11% of them contained nitrosodiethylamine. Mutagenicity assays were performed in Salmonella typhimurium. Strains TA 98 and TA 100 were used in absence and presence of S9 mix. A dose‐response curve of the mutagenic activity was observed in TA 100 with S9 mix. Unscheduled DNA synthesis assay also confirmed that the purified extracts of hams and sausages at doses as low as 1 ppb are inducers of damage to DNA of human foetal lung cells.
Use of ultrafiltration for preparing improved tomato pulp
Authors: PORRETTA SEBASTIANO , CARPI GIUSEPPE , DALL'AGLIO GIANFRANCO , GHIZZONI CLAUDIO
Published: July 2010

The characteristics of high‐quality tomato pulp (commercial def.: crushed or diced tomatoes with about 30% tomato juice as packing medium) canned with tomato juice pulp enriched by ultrafiltration as packing medium were compared with those covered with conventional vacuum‐concentrated juice.

Both hot‐ and cold‐break products were prepared and those containing 20% serum‐reduced packing juice proved to be the best, showing no signs of syneresis on storage and with improvements in sensory properties, colour and non‐enzymatic browning; some volatile components were reduced.
Production of clear guava nectar
Authors: CHAN WAI‐YUNG , CHIANG BEEN‐HUANG
Published: July 2010

Three fining methods were tested for use in producing clarified guava nectar. The enzyme hydrolysis method, especially treating the guava purée with 1000ppm of pectinase at 50°C for 3 h, accomplished satisfactory clarification but caused severe losses in volatile components, pre‐treating the purée with 100ppm of pectinase for 1 h greatly facilitated the subsequent bentonite or ultrafiltration clarification processes, and both the bentonite treatment and the ultrafiltration process yielded clarified product, but the ultrafiltered product had less loss of volatiles. However, to achieve storage stability, a membrane of lower than 100000 dalton molecular weight cut‐off should be used.
A kinetic study of salt diffusion in potato at high temperature
Authors: LIU HUA
Published: July 2010

The apparent diffusion coefficient of sodium chloride in potato was determined from the change in average concentration in cylindrical potato pieces with time when surrounded by salt solution of between 1 and 5% concentration. Measurements were made at temperatures in the range 50–120°C. The apparent diffusion coefficient of salt in potato is temperature dependent and follows the Arrhenius equation, with activation energies of 20–24 kJ mol‐1, decreasing with increasing concentration within the temperature range 70–120°C. The apparent diffusion coefficient increases with concentration. Below 60°C the Fickian diffusion equation did not predict the experimental results accurately because of changes in the dimensions and structure of the potato caused by osmosis.
Kinetics of enzymic hydrolysis of cassava flour starch — optimization and modelling
Authors: WALISZWESKI KRZYSZTOF N. , ALVARADO MIGUEL GARCIA , MEDINA JAVIER DE LA CRUZ
Published: July 2010

This study was conducted to model the kinetics of cassava flour hydrolysis by Miles Taka‐Therm L–170 alpha amylase and Diazyme L–200 glucoamylase to produce glucose syrup. Maximum starch concentration was 33% due to a controlled process of flour gelatinization by gradual temperature increase, and parallel starch hydrolysis by thermostable alpha amylase activity, preventing excess viscosity. The time of hydrolysis was two and half hours of alpha amylase activity and 36 h of glucoamylase activity with the final yield of 90–93% of glucose. Exponential hyperbolic models were obtained to predict the kinetic of hydrolysis both amylase and glucoamylase, with a generalized correlation coefficient >0.94.
Storage of common mushroom under controlled atmospheres
Authors: BRIONES GUADALUPE LOPEZ , VAROQUAUX PATRICK , CHAMBROY YVES , BOUQUANT JAMES , BUREAU GILBERT , PASCAT BERNARD
Published: July 2010

The effect of controlled atmosphere (CA) on the shelf‐life of the common mushroom (Agaricus bisporus) was assessed using six parameters correlated with its commerical qualities. Low CO2 concentrations (up to 2.5%) reduced brown discolouration compared to the control in air. Higher CO2 concentrations enhanced both internal and external browning. Low O2 concentrations reduced growth of micro‐organisms, including pseudomonads. Respiration rate, when the mushrooms are placed again in normal air, is proportional to CO2 concentration during storage suggesting that CO2 exhibits a phytotoxic effect on mushrooms. A lower mannitol content was noted in mushrooms stored under CA than those stored in air (control). Mushrooms stored in a 5% CO2 atmosphere for 7 days did not break their veil but their texture was very soft and spongy. Texture losses decreased when CO2 concentrations increased.
Influence of process variables on the drying of potato slices
Authors: MAGEE T. RONALD A. , WILKINSON CAROLE P.D.
Published: July 2010

Investigation of the effects of varying air velocity, slice thickness, and pre‐treatment with sodium chloride solutions and surface active agents on drying potato slices indicated that the drying occurred entirely in the falling rate period and was controlled by the mechanism of liquid diffusion. The rate of drying, and therefore the diffusion coefficients, increased with the addition of sodium chloride and surface active agents. Diffusion coefficients were also influenced by air velocity and slice thickness, suggesting that the rate of drying of potato slices is controlled by a combination of internal and external resistances.
Effect of screw profile on extrusion‐cooking of wheat flour by a twin‐screw extruder
Authors: YEH AN‐I , HWANG SHIUAN‐JER
Published: July 2010

The effects of forward‐, reverse‐, and no‐flight screw elements on the residence time distribution, dispersion number, and product properties were investigated in extrusion cooking of wheat flours in a twin‐screw extruder. Mean residence times of 46.5s with a forward element increased to 59.6s with a reverse flight and 67.6s with a no‐flight element. Dispersion numbers were 0.051, 0.056, and 0.075 respectively. The no‐flight element reduced cooking loss and increased the degree of gelatinization of products.
The influence of calcium on the chromogenic Limulus Amoebocyte Lysate assay of lipopolysaccharide endotoxins in liquid milk
Authors: LAWRENCE LORNA M. , GILMOUR ARTHUR , PEARCE JACK
Published: July 2010

Calcium ions were shown to have a profound effect on the chromogenic Limulus Amoebocyte Lysate assay of lipopolysaccharides in liquid milk. There appeared to be two optima within the range of 0–1.0 mM added calcium chloride, with an inhibition of the assay at calcium ion concentrations between 0.2 and 0.4 mM, and above 0.6 mM. With products of this nature, standardization of calcium ion content is required for meaningful comparisons of results between samples. Further investigation is required to assess the possible influence of other serum constituents.
Measuring and modelling the water vapour desorption in sunflower seed
Authors: ROVEDO CLARA O. , AGUERRE ROBERTO J. , SUAREZ CONSTANTINO
Published: July 2010

Water activities of sunflower seed (whole), hull and endosperm were measured at 25, 40 and 50°C and different moisture contents by means of an electronic aw‐meter in the range 0.199‐0.867. Based on the equilibrium between the water in air and a constant moisture specimen, the method permits a direct measurement of the isosteres and was used to estimate the variation of the isosteric heat with moisture content. In the range of temperature investigated it was found that the isosteric heat is pracitically independent of temperature. the hygroscopic equilibrium data of the different materials were modelled by a BET‐type two parameter isotherm for the whole range of water activity investigated.
Errors in blanching calculations caused by using one common value of thermal diffusivity for different vegetables
Authors: HOUGH GUILLERMO , ALZAMORA STELLA M.
Published: July 2010

The errors in calculations of blanching time and enzyme inactivation (decimal reduction time) when one common value of thermal diffusivity is adopted for all vegetables are considered. Different rates of heat transfer (negligible heat transfer resistance and blanching in water by natural convection), food size, decimal reduction time of the enzyme (D), and reciprocal slope of the log D vs. temperature curve (parameter z), were analysed. These variables influenced the blanching time more than the thermal diffusivity and consequently, for many industrial situations, a single thermal diffusivity value of 1.5 x 10‐7m2s‐1 could be used without causing significant errors in blanching calculations.
Interaction of malondialdehyde with biological molecules — new trends about reactivity and significance
Authors: AUBOURG SANTIAGO P.
Published: July 2010

Malonyldialdehyde (malondialdehyde, MDA) is one of the most significant of the wide range of metabolic or deteriorative products of lipid damage. Its formation during food processing and storage is widely used in quality control. Its ability to react with ‐ NH2group is also of great carcinogenic or mutagenic interest because of its possible interaction with important constituents (e.g. free amino acids, proteins, nucleic acids, and amino phospholipids) of foods during and after processing. Special attention has been given to the role played by MDA in the formation of the age pigments, commonly named as ‘lipofuscin’.

The present review compiles the general characteristics that have made MDA the most widely studied lipid metabolite, and the progress achieved in knowledge of MDA reactivity with biological molecules. the special stress given to the structural elucidation of the structures of these products have led to a new perspective about the role played by MDA.
Desalting and recovery of flavour compounds from salted shrimp processing waste water by membrane processes
Authors: LIN CHANG Y. , CHIANG BEEN H.
Published: July 2010

Diafiltration (DF) and electrodialysis (ED) were studied to remove salt and to recover flavour compounds from salted shrimp processing waste water. Using a loose reverse osmosis membrane, the DF process removed about 93% salt, but recovered less than 50% of free amino acids and nucleotides. At high operation current density, the ED process removed 85% salt and recovered more than 70% of flavour compounds, and appeared to be a more effective method for recovering flavour compounds from the salted shrimp processing waste water.
Thermal destruction of thiamin in different types of pre‐packaged minced meats
Authors: AWONORIN S.O. , AYOADE J.A.
Published: July 2010

The changes in thiamin content, pH, and moisture content of some pre‐packaged minced meats during heat processing were measured. Minced pork, lamb, turkey and guinea fowl meat samples of weights ranging from 20 to 75g were heat processed at 90 and 90°C for 15 min to 5h. the data obtained showed that a considerable amount of thiamin was lost during processing, and that the retention of thiamin decreased with increasing process temperatrue, time and cooking losses. the results also suggested that high initial sample pH may tend to decrease thiamin retention in minced meat on application of heat.
Iranian breads supplemented with amaranth flour
Authors: SAMIYI MITRA , ASHRAF HEA‐RAN LEE
Published: July 2010

Amaranth can be grown in many drought‐prone semitropical countries to produce a high‐protein flour which is a nutritional complement to wheat flour. Replacement of up to 30% of wheat in three Iranian breads similar to those in other semitropical countries produced little adverse effect on sensory attributes but improved calculated nutrient composition.
Fat stability and amino acids in south Indian tea seeds
Authors: RAVICHANDRAN RAMASWAMY
Published: July 2010

The composition and storage stability of south Indian tea‐seed oil stored at 25° and 37°C, in different containers (glass, tin plate, PVC), with or without antioxidants has been studied. the crude tea‐seed oil is highly stable to peroxide formation, but after refining or bleaching, antioxidants are required. the amino acid levels of oil‐free tea‐seed meal, prepared from three varieties of south Indian tea‐seed kernels with 31‐38% protein content were also examined and some possible utilization of these protein rich tea‐seed meals is described.
Rheological characterization of some Nigerian traditional soups
Authors: SOPADE PETER A. , KASSUM AFODIA L. , ADAMU DAHIRU J. M.
Published: July 2010

The rheological behaviour of five traditional Nigerian soups with potential for industrial processing was investigated in the temperature range 10‐70°C, using a rotational viscometer at speeds of 10, 20, 50, and 100rev min‐1. the decrease in apparent viscosity with speed was well described by an empirical power‐law equation, with indices between 0.19 and 0.41, indicating pseudoplastic behaviour. Viscosity decreased with temperature and was described by the Arrhenius equation with activation energies from 8.3‐14.4 MJ mol‐1.
1H‐NMR study of bovine myoglobin autoxidation. Influence of muscle type and time post mortem
Authors: FOUCAT LOÏC , RENERRE MICHEL , GATELLIER PHILIPPE , ANTON MARC
Published: July 2010

1H NMR spectroscopy was used to determine first order rate constants at four temperatures (300, 304, 308, 312 K) and activation energies of the autoxidation reaction for oxymyoglobin. the haeminic pigment was purified from two bovine muscles with different colour stabilities (psoas major (PM) and longissimus lumborum (LL)) at 2h (day 0) and 192 h (day 8) post mortem. to characterize this autoxidation reaction, we have focused attention on the time‐temperature dependent disappearance of the Val‐E11 methyl group signal. This study showed that, whatever the time post mortem, although the myoglobin autoxidation rate was greater for PM than for LL muscle, the activation energies were similar. It was also worth noting that, in the range 300–312 K, the average ratio of autoxidation rate constants between day 8 and day 0 was near 1.6 for the two muscles studied. It is reasonable to think that oxidative processes developed during 8 days meat storage have led to a structural change within the cavity of the heme pocket of the myoglobins. Moreover, only one orientation of the porphyrin within the heme pocket was noted for the two muscles studied.
Rhizobium trifoliicapsular polysaccharide: a novel biopolymer with striking physical properties
Authors: KASAPIS STEFAN
Published: July 2010

The physical properties of the capsular polysaccharide ofRhizobium Trifolii(CPS) were investigated. Viscosity measurements provided information about the hydrodynamic volume of single coils, the perturbation of solvent flow and the shear‐thinning behaviour of concentrated solutions. Changes in chain geometry and the development of an intermolecular network as a function of temperature were monitored using the techniques of optical rotation and dynamic oscillation. Finally, analysis of calorimetric thermograms elucidated the type of interactions between CPS and the bacterial levan. Overall, theRhizobiumpolysaccharide was found to form thermally‐reversible gels at an extremely low ‘minimum critical gelling concentration’ (co∼ 0.35gl‐1). At temperatures above the gel melting point (∼ 48°C), however, the compact polymer coils entangled at comparatively high concentrations (about 60 times higher than co). In the presence of a highly branched levan, the thermal stability of ordered CPS structures increased as a consequence of thermodynamic incompatibility between the two polymers.