bluuebunny/crossref_metadata_2025 huggingface dataset:
Quality changes in frozen Brussels sprouts during storage. I. Sensory characteristics and residual enzyme activities
Authors: STEINBUCH E. , HILHORST R. A. , KLOP W. , ROBBERS J. E. , ROL W. , VAN DER VUURST DE VRIES R. G.
Published: July 2010

Sensory evaluation and quantitative analyses of catalase, peroxidase and lipoxygenase were performed in frozen Brussels sprouts during storage at three different temperatures. Within 6 weeks at –4°C all sensory attributes had reached the limit of acceptability, while peroxidase activity increased in the same period. At the end of this period catalase activity had increased strongly. Colour and flavour decreased slowly during 11 months storage at –9°C, while texture remained on a constant level. After 4 months at –9°C a slight catalase activity became detectable. At –18°C no detectable changes occurred during 11 months. Characterization of the preliminary blanching process in terms of residual activities of peroxidase and catalase remains possible after prolonged storage, provided microbial growth can be excluded.
Quality changes in frozen Brussels sprouts during storage. II. Objective quality parameters: texture, colour, ascorbic acid content and microbiological growth
Authors: TIJSKENS L. M. M. , KOEK P. C. , MEER M. A. VAN DER , SCHIJVENS E. P. H. M. , WITTE Y. DE
Published: July 2010

Brussels sprouts were stored at –18°C, –9°C and –4°C. During this storage, the colour of whole Brussels sprouts and Brussels sprouts slurry, measured as the greenness (Hunter –a value), decreased, probably can be described as a first order decay. The reflection at 680 nm of Brussels sprout slurry measures possibly the constant sum of chlorophyll and pheophytin. This can be a useful indication of the initial colour of the product. Also the ascorbic acid content can be a useful quality index, provided the initial level is known.

Although not a very sensitive one, the shear force seems to be the most reliable textural parameter.

From microbiological point of view, a storage temperature of –18°C as well as –9°C, is quite acceptable.
Sensory analysis of bitterness in apple wine
Authors: ROOZEN J. P. , VAN BUREN J. P.
Published: July 2010

A dilution test determining the occurrence of basic tastes in apple wine and hard cider showed sourness, sweetness and bitterness to be present. For selection of assessors a bitterness standard was defined as a taste difference between two apple wines. Ranking and paired comparison tests were used for analysis of bitterness levels. Additions to the fermentations improving the growing conditions for the yeast decreased the bitterness of the apple wine.
Stability of β‐carotene in isolated systems
Authors: ARYA S. S. , NATESAN V. , PARIHAR D. B. , VIJAYARAGHAVAN P. K.
Published: July 2010

The effects of water activity, antioxidants and fatty acid methyl esters on the stability of β‐carotene in isolated model systems has been investigated. The rate of β‐carotene degradation decreases with the increase in water activity. Both BHA and PG stabilized β‐carotene at all water activity levels. Methyl stearate and oleate enhanced the stability of β‐carotene. Methyl linoleate stabilized β‐carotene during initial stages of slow oxidation after which it exhibited a strong prooxidant effect.
The rapid detection of polyphosphate in broiler chicken breast muscle
Authors: GREY T. C. , ROBINSON D. , JONES J. M.
Published: July 2010

A method for rapid detection of the presence of injected polyphosphate or a mixture of polyphosphate and sodium chloride solutions in broiler breast muscle has been developed. Detection is based on the ratio of sodium and phosphorus (as P2O5) concentrations found in a trichloroacetic acid (TCA) extract of the muscle. Comparison of acid digested and undigested TCA extracts showed that the presence of these added salts could be demonstrated equally well without acid digestion. The method has been satisfactorily applied to the analysis of deep‐frozen broilers purchased from supermarkets.
The production of soluble fish protein solution for use in fish sauce manufacture I. The use of added enzymes
Authors: BEDDOWS C. G. , ARDESHIR A. G.
Published: July 2010

The production of a fish hydrolysate, using plant proteases, which could be added to traditionally fermented fish sauce to increase the total volume without affecting the overall nutritional quality was investigated.

The effect of adding bromelain, papain or ficin, on the rate of hydrolysis and the extent of the conversion of insoluble fish protein, to soluble nitrogen was examined. The conditions employed were similar to those used in traditional fish sauce manufacture but both whole and minced Ikanbilis (Stolephorus sp.) were investigated. Measurement of the extent of hydrolysis after 1, 2, 4, 7, 14, 27, 28 and 35 days at 33°C showed that bromelain tended to give slightly better results with some 65% of the protein being hydrolysed. The effect of temperature enzyme, co‐enzyme and salt concentrations for the hydrolysis by bromelain were investigated and the optimum conditions established at the pH normally found in fish sauce production. The hydrolysate produced in 18–21 days was comparable to traditional fish sauce in the distribution and concentrations of nitrogenous compounds and had very little aroma. The product could be added to the traditional sauce without affecting its quality.
The production of soluble fish protein solution for use in fish sauce manufacture II. The use of acids at ambient temperature
Authors: BEDDOWS C. G. , ARDESHIR A. G.
Published: July 2010

When batches of Ikanbilis were acidified using hydrochloric acid to pH 2.0–3.5 at 30°C, the rate and extent of hydrolysis of the fish protein and the rate of formation of supernatant liquor were increased.

The effect of pH and salt concentration was investigated. Although the presence of salt generally decreased the extent of proteolysis, it made the mixtures easier to filter. The optimum conditions were either pH 2.0 and 10% salt (w/w) or pH 3.0 and 15% salt (w/w). The extent of fish protein hydrolysed was comparable to the natural fermentation and the concentrations and distribution of soluble nitrogen were very similar to those obtained in the traditionally produced sauces. This liquor was produced within 6 days. The natural fermentation takes 4–9 months.

The use of formic acid was investigated and showed no particular advantage.

When the pH of the acid ensiled mixtures was adjusted above 4.2, calcium phosphate precipitated; this was removed by filtration.

The effect of adding alkaline ensiled fish to acid ensiled fish mixtures (the pH of which had been re‐adjusted) was investigated. The amount of insoluble protein hydrolysed increased to a limited extent.

As the solutions produced by acid ensilation had very little aroma or taste but had a high soluble nitrogen content, they could be used to add to traditionally prepared fish sauce in order to increase the net volume which would increase the rate of production.
The prediction of water activity in aqueous solutions in connection with intermediate moisture foods IV. aW Prediction in aqueous non electrolyte solutions
Authors: CHIRIFE J. , FONTAN C. FERRO , BENMERGUI E.A.
Published: July 2010

A systematic survey was made of water activity reduction in single non electrolyte aqueous solutions together with an examination of the theoretical aspects of aW predictions. The prediction of aW in multicomponent aqueous solutions of non electrolytes as well as of mixed strong electrolyte–non electrolyte solutions was also studied.
Applications of high pressure liquid chromatography* to food analysis
Authors: MACRAE R.
Published: July 2010

High pressure liquid chromatography (HPLC) is becoming widely accepted as an invaluable technique for the analysis of many food components. In many instances HPLC methods have replaced laborious analyses and, in general, the chromatographic methods are more specific and precise, coupled with a significant reduction in analysis times.

A number of articles, e.g. Battaglia (1977), Rapp & Ziegler (1975), Wildanger (1975a) and Saxby (1978a,b), have been written reviewing the applications of HPLC to food analysis, but these have not covered the literature comprehensively. This is attempted here, preceded by a brief description of the methodology and instrumentation of HPLC.
Purification of crude glucose solution from the enzymatic hydrolysis of potato waste, by solvent precipitation, ultrafiltration and ion exchange
Authors: MORETON R. S. , GIBSON JEAN
Published: July 2010

A crude, dilute glucose solution produced by the enzymatic hydrolysis of waste from a dehydrated potato plant, contained high concentrations of non‐carbohydrate and coloured materials. Purification using solvent precipitation, ultrafiltration and ion exchange, reduced the concentration of non‐carbohydrate materials from 27% to 3%, and increased the glucose concentration from 53% to 96% of the total dissolved solids. The purified material was suitable for use in some food applications or as a fermentation substrate.
The resistance of dry spores of Bacillus subtilis var. globigii (NCIB 8058) to solutions of hydrogen peroxide in relation to aseptic packaging
Authors: SMITH Q. J. , BROWN K. L.
Published: July 2010

The resistance to solutions of hydrogen peroxide of dry spores of Bacillus subtilis var. globigii (NCIB 8058) was studied between concentrations of 10 and 30% (w/v) at temperatures from 20 to 50°C. Logarithmic relationships were obtained between decimal reduction time and temperature at different concentrations of hydrogen peroxide. The difference between the resistance of wet and dry spores to hydrogen peroxide is discussed.
Colourless sunflower protein products: chemical and nutritional evaluation of the presence of phenolic compounds
Authors: BAU H. M. , DEBRY G.
Published: July 2010

This study describes a simple process for preparing a sunflower product from dehulled sunflower seeds. The processed products, apart from the high content of lipid (39%), are whole foods, white in colour, with a fibrous or granular texture and acceptable odour. They contain 27–29% proteins, 4% ash, 3.9% fibres and small amounts of phenolic compounds. Furthermore, their PER values can equal that of casein when 2% lysine is added. However, the extraction process causes a loss in lipid (25–30%), a fall in lysine and cystine content and a slight fall in soluble protein.
Control of spoilage in vacuum packaged dark, firm, dry (DFD) meat
Authors: NEWTON K. G. , GILL C. O.
Published: July 2010

Early spoilage of vacuum‐packaged DFD meat, due to green discoloration and development of undesirable odours and flavours, can be prevented by addition of small quantities of citrate buffer to the meat before packaging. This treatment extends the storage life to that of vacuum‐packaged normal meat, both appearance in the pack and flavour being acceptable after 12 weeks storage at –1°C. However, steaks cut from the vacuum‐packed primal cuts remained darker in appearance than normal pH controls and spoiled more rapidly during aerobic storage.
Determination of thermal process schedule for Totapuri mango
Authors: NATH NIRANKAR , RANGANNA S.
Published: July 2010

The values for thermal inactivation of pectinesterase (PE) in Totapuri mango syrup homogenate are F18.56208.8= 1.00 and D21.4208.8= 0.456 at pH 3.6. The F value is equivalent to 2.19 D. In commercial canning a 3 D process is recommended which is adequate to inactivate the PE, the natural microflora consisting of gram‐positive and gram‐negative nonsporulating rods and cocci, and the test organism Clostridium pasteurianum which is able to grow in mango preparations at pH 3.8 and above. Bacillus coagulans which causes flat‐sour spoilage does not grow in mango preparations. Process times calculated by the graphical method are compared with the values found by formula method using six different procedures. Process requirements under different initial and processing temperatures are given.
Storage life of chilled Patagonian hake (Merluccius hubbsi)
Authors: LUPÍN H. M. , GIANNINI D. H. , SOULÉ C. L. , DAVIDOVICH L. A. , BOERI R. L.
Published: July 2010

The storage life of iced Patagonian hake (Merluccius hubbsi) was studied. Seasonal changes were investigated by means of organoleptic assessments (raw and cooked), total volatile bases (TVB) and pH.

During summer‐time (December to March) the keeping time, from the edibility point of view, for round hake in ice is not more than 9 to 10 days; in the remaining months the storage life under the same conditions is up to 14 to 15 days.

The difference could be due to the biological condition of hake during and after the spawning time (end of spring‐beginning of summer), the shallow and temperate waters of the fishing grounds in summer, and the heavy feeding after spawning.

Comparison trials between gutted and ungutted hake in ice, and between ungutted hake in ice and in chilled sea water (CSW) were also performed.

The duration of rigor mortis of whole hake stored in ice, and the feasibility of quality assessment by an electronic device were also studied.
A modern dry‐salting process for Wiltshire bacon
Authors: TAYLOR A. A. , SHAW B. G. , JOLLEY P. D.
Published: July 2010

Bacon made by a 5‐day process using brine injection followed by dry‐salting has been compared with that made by a longer conventional Wiltshire process. The eating quality and appearance of the two bacons were similar. The slightly poorer storage stability of dry‐salted back in vacuum packs was attributed to a low salt concentration which could be corrected by increased brine injection in this region. Dry‐salting slightly improved the storage stability of collar in vacuum packs because initial bacterial counts were lower than in the immersion‐cured. Comparison of dry‐salted bacons made with and without nitrate in the injection brine showed that nitrate did not affect nitrite level during vacuum‐packed storage.
Changes in the free ‐NH2, free ‐CO2H and titratable acidity of meat proteins
Authors: MADOVI P. B.
Published: July 2010

The 2, 4, 6‐trinitrobenzene sulphonic acid (TNBS) spectrophotometric assay and formol titration were used to measure changes in free ‐NH2 and free ‐CO2H respectively, in meat proteins dissolved in 3% sodium dodecyl sulphate (SDS). Changes in the titratable acidity of the meats was also determined. The free ‐NH2 groups were found to decrease markedly with cooking while ‐CO2H remained relatively constant. Intermediate moisture beef (Longissimus dorsi) processed and stored at 38°C showed the free groups increasing for up to 8 weeks' storage due to proteolysis, followed later by a sharp fall due to cross‐linking. But titratable acidity of the IM beef samples continued to rise with storage.
The determination of fluorine in coffee and tea using a microprocessor coupled with a fluoride ion‐selective electrode
Authors: MOODY G. J. , ONG B. , QUINLAN K. , RIAH A. H. , THOMAS J. D. R.
Published: July 2010

The fluoride content of tea and coffee as normally brewed, and after Schöniger oxygen flask combustion, has been determined with a fluoride ion‐selective electrode coupled to a microprocessor analyser in two of its operational modes. Up to forty samples per hour can be assayed in the CONCN mode and the results compare favourably with the known addition (KA) back‐up mode.
Effects of processing on the thiamin, riboflavin and protein contents of cowpeas (Vigna unguiculata (L) Walp) II. Alkali (‘potash’) treatment
Authors: EDIJALA J. K.
Published: July 2010

Alkali treatment of cowpeas using ‘potash’(sodium sesquicarbonate) and sodium bicarbonate caused severe losses of thiamin and riboflavin but had no significant effect on the protein content in terms of total nitrogen. The vitamin losses were not dependent on the pH but on the concentration of the alkaline solutions. The reduction in cooking time by the use of alkali was significant only at high concentrations but the resultant products were not acceptable organoleptically. As the vitamin losses were high even with low concentrations of alkali the traditional Nigerian use of ‘potash’ is not advocated. In addition, there is a possible latent danger to health with ‘potash’ treatment of cowpeas because of the possible undesirable formation of lysinoalanine.
Volatiles of apples (var. ‘Schone van Boskoop’): isolation and identification
Authors: FEYS M. , TOBBACK P. , MAES E.
Published: July 2010

A simple method for the analysis of apple volatiles has been developed. By means of a modified vacuum‐cold trap distillation an aqueous solution of volatiles, ready for direct GLC‐analysis, is obtained.

Formation of artefacts (e.g. volatile aldehydes) during homogenization of the apple tissue was prevented by addition of trichloroacetic acid. About fifteen volatiles of the apple variety ‘Schone van Boskoop’ have been identified and quantified. More than 85% of the total volatile fraction are alcohols. The recovery for the different volatiles ranged from 60 to 95% depending on the nature of the compounds.

In a dichloromethane extract of the distillate a few minor compounds, mostly esters, were identified by mass spectrometric analysis.
Methods of measuring green colour and chlorophyll content of apple fruit
Authors: KNEE M.
Published: July 2010

The change in colour from green to yellow during ripening of apples depends essentially upon disappearance of chlorophyll. Chlorophyll concentration in the fruit peel can be estimated by extraction and spectrophotometry or in terms of the reflectance of the apple surface at 675 nm. The reflectance and chlorophyll concentration data do not conform to the Kubelka‐Munk equation. Reflectance at 675 nm is highly correlated with colour descriptions derived from reflectance spectra. Although a reflectance spectrophotometer gave the most precise reflectance measurements, a simple colorimetric device was modified to give nearly equivalent results.
Taste properties of cocoa drinks with an added bitter/sweet sugar: intensity/time effects
Authors: BIRCH G. G. , OGUNMOYELA G.
Published: July 2010

Cocoa drinks treated with either sucrose or the bitter/sweet sugar, methyl α‐D‐mannopyranoside were evaluated for their intensity/time response determined by taste panellists using a moving chart recorder. Both additives caused an increase in persistence as well as intensity of response, sucrose for sweetness and methyl α‐D‐mannopyranoside for bitterness.

Tasting of the sucrose‐treated drinks, after presaturating panellists' tongues with quinine sulphate solutions, caused no significant differences in perceived sweetness. However, presaturating panellists' tongues with sucrose solution did cause significant differences in bitterness perception of the drinks containing methyl α‐D‐mannopyranoside.

These results accord with a previous observation of the taste response to methyl α‐D‐mannopyranoside in pure water and suggest that the bitter/sweet molecule may exert its effect by simultaneously spanning both basic taste receptors.
Ice morphology in frozen beef
Authors: BEVILACQUA A. E. , ZARITZKY N. E.
Published: July 2010

A histological study was made of pieces of meat which had been frozen from one side, in conditions where the direction of the heat flux was approximately unidirectional and perpendicular to the muscle fibres. The morphology of the ice crystals in tissue frozen under various conditions was studied, and the range of freezing velocities over which no intracellular ice existed, was established. The average diameter D, of ice crystals, measured in different experiments and at different levels in the same piece of meat was related to the characteristic freezing time tc, by the equation:

D= a + b log tc
The stability of Clostridium botulinum type E toxin in salty and/or acid environment
Authors: HUS H. H. , PETERSEN E. RYE
Published: July 2010

The stability of preformed Clostridium botulinum type E toxin in sterile buffer‐and salt‐solutions and in some commercial fish products has been examined. It has been found that progenitor toxin is stable for weeks at room temperature in sterile culture filtrate, spoiling fish and in low acid fish products and that it is unaffected by sterile saturated salt (NaCl) solutions and in salted fish. In high acid feed fish (fish silage pH 2–4) some inconsistant increased toxin titres have been observed.

The activated toxin, on the other hand, decreased and increased in titre during several weeks of storage in culture filtrate with added trypsin. In sterile NaCl solutions the titre decreased by a factor of 10 to that of a progenitor toxin, but in spoiling raw and salted fish toxicity was lost when pH exceeded 7.5.

The public health significance of these results is discussed.
Principles and practice of near infra‐red (NIR) reflectance analysis
Authors: OSBORNE B. G.
Published: July 2010

Near infra‐red (NIR) analysis is now widely used for the rapid analysis of many agricultural and food products for protein, moisture, oil, starch, sucrose, fibre, grain texture and lysine. Research has shown that the technique can also be used for the prediction of malting quality of barley, baking quality of wheat and measurement of the degree of starch damage in flour.

The technique of NIR analysis uses very small differences in absorption of NIR radiation at wavelengths corresponding to overtones and combinations of fundamental IR frequences of chemical functional groups that are characteristic of particular analytes. Complex regression mathematics is used to transform these absorption measurements into an analytical result.
The fluidization characteristics of potato chips
Authors: McLAIN H. D. , McKAY G.
Published: July 2010

The fluidization characteristics of potato chips and potato cuboids have been investigated and the results compared with correlations obtained for the fluidization of plastic cuboids.

It was found that potato chips and cuboids behaved in a similar manner to the plastic cuboids and that the plastic cuboid correlations may be used to predict the performance of potato chips and cuboids.

Certain fluidization parameters may be used to predict the minimum transportation velocity of potato chips in vertical pipelines.
Correlation between iodine number and proton relaxation times in maize oil
Authors: BROSIO E. , CONTI F. , DI NOLA A. , SYKORA S.
Published: July 2010

We have found a good correlation between the iodine number of maize oil and an empirical parameter‐related to the proton T1 relaxation time determined by means of low resolution pulsed nuclear magnetic resonance spectroscopy. This result opens a way to fast and reliable determination of the iodine number during oil hydrogenation.
Some factors affecting oxygen transmission rates of plastic films for vacuum packaging of meat
Authors: EUSTACE I. J.
Published: July 2010

Film composition, temperature and humidity affect the oxygen transmission rates of some films used for the vacuum packaging of meat.

Of the transparent films suitable for meat included in the investigation, those which include polyvinyl alcohol or polyvinylidene chloride offer the greatest barriers to oxygen. Oxygen transmission rates (OTR) at 3.5°C (i.e. near the recommended storage temperature for vacuum packed chilled meat) are only 5–15% of those at 25°C.

High humidity increases the OTR of nylon based films, but the effect is less marked at 3.5°C than at 25°C. At 25°C the OTR reduces to rates expected at 75% r.h. within 50 hr of a change in relative humidity from 98 to 75%. Humidity has a negligible effect on the OTR of films containing PVDC.

Shrinking of heat shrinkable films reduces the oxygen transmission rate approximately in proportion to the reduction in surface area.

The practical implications of the findings are discussed. Relative humidities near 100% r.h. for OTR measurements probably closely simulate the r.h. conditions within cartons of vacuum packaged meat. OTR measured at 20–25°C do not indicate the performance of a film at 0°C, although they do provide a guide to the performance of a given film relative to alternative films of similar composition.
Preparation of blood globin through carboxymethyl cellulose chromatography
Authors: SATO Y. , HAYAKAWA S. , HAYAKAWA M.
Published: July 2010

A simple and inexpensive procedure for globin preparation from blood of various animals was developed in order to use globin as human food. Carboxymethyl cellulose was most effective among some cation exchangers tested, although amounts of haemoglobin applied to 1 g of the exchanger should be limited to less than 70 mg. The behaviour of adsorbing haem or haemin to the exchanger could not be explained only by a general theory of ion exchange chromatography. Yields and Fe contents of globin preparations from various haemoglobins by this procedure ranged from 67 to 80% and from 0.008 to 0.03% respectively, except for a chicken haemoglobin sample.
Physical characteristics of an air classified potato starch
Authors: HOLM F.
Published: July 2010

The physical properties of potato starch concentrate (96% starch, dry basis) produced by air classification of dried potatoes have been examined. The properties of the starch product are in many respects different from those of commercial potato starch. At a storage temperature of 20°C the product will be stable over long periods at water activities between 0.4 and 0.5. The concentrate possesses high water binding capacity which is a desirable property within food processing. Viscosity studies show that the concentrate is stable towards heat, mechanical shear, moderately acidic conditions, and that the paste viscosities are higher than for potato starch except for the gelatinization peak which indicates restricted swelling of the granules. The acid stability, rate of retro‐gradation and freeze‐thaw stability are very similar to commercial potato starch.
The storage life of iced southern blue whiting (Micromesistius australis)
Authors: BARASSI C. A. , BOERI R. L. , CRUPKIN M. , DAVIDOVICH L. A. , GIANNINI D. H. , SOULÉ C. L. , TRUCCO R. E. , LUPÍN H. M.
Published: July 2010

The storage life of iced southern blue whiting (Micromesistius australis) was studied. Pre‐ and post‐spawning characteristics were investigated by means of organoleptic assessments of raw and cooked fish, total volatile bases, reduced viscosity of high ionic strength muscle extract and GR Torrymeter readings. Results show a great influence of the biological condition on the keeping time in ice.

The results suggest that in pre‐spawning condition the whole fish can be stored up to 12 days while in post‐spawning condition the keeping time cannot exceed 6 days.

The gutting of the fish could lengthen the possible storage time in the post‐spawning condition for up to 2 days. Nevertheless the post‐spawning fish quickly loses its quality 2–3 days after catching.

The possibility of utilizing standard white fish processing machines and the influence of parasites are also discussed.
Behaviour of the mechanically separated flesh of some common fish species of the Mexican shrimp by‐catch during storage at −20°C
Authors: TABLEROS M. A. , YOUNG R. H.
Published: July 2010

Deboned minces prepared from fish species predominant in the Mexican shrimp by‐catch were examined with respect to their stability during storage for 10 months at –20°C. Reductions in the extractability of salt‐soluble proteins occurred to varying levels in all samples, particularly in the initial storage phase. These changes were shown to influence the textural characteristics of the minces, albeit to a minimal extent. Considerable variability in the colour of minces from different species was observed and a washing procedure which effectively removes dark pigments is described. In general, the acceptability of the products was maintained throughout the storage period. It is thus concluded that deboning and the freezing of the resultant minces could offer a potential means of processing currently wasted by‐catch fish into human food.
Separation of anthocyanins by adsorption on acid alumina
Authors: PIFFERI P. G. , VACCARI A.
Published: July 2010

The conditions have been determined for achieving an effective separation on acid alumina of polyhydroxylated anthocyanins from others.

The adsorption isotherms for some anthocyanins are also given and the behaviour of methanol, ethanol and propanol solutions has been examined.
Potato flour as partial replacement of wheat flour in bread: baking studies and nutritional value of bread containing graded levels of potato flour*
Authors: YÁNEZ E. , BALLESTER D. , WUTH H. , ORREGO W. , GATTÁS V. , ESTAY S.
Published: July 2010

Potato flour (PF) is a material that does not differ significantly from wheat flour (WF) with regards to its physical appearance and chemical composition. For that reason it may be used in bread making. In this study mixtures of wheat flour and potato flour were prepared containing PF at levels of 0, 2, 4, 6, 8 and 10%. The farinograph properties of wheat flour affected by addition of potato flour were studied. Water absorption increased gradually from 62% for WF to 79% for blend with 8% PF. Other parameters such as development time, weakening of dough (Brabender units) and valorimeter value (W) were adversely modified by the addition of potato flour. The bread properties were studied using mixtures containing 0, 2, 4, 6, 8, 10 and 15% PF. The substitution of WF produced increases in water absorption, loaf weight and loaf volume as compared to all‐wheat bread. In addition, bread containing PF retained moisture for longer periods than normal bread. Loaves made from wheat flour and 2, 4, 6, 8 and 10% potato flour were tested for their chemical composition and protein efficiency ratio (PER) in the rat. Moisture of bread increased with each increase in the level of potato flour substitution. The protein content of bread showed a progressive fall from 6.8% (at 4% level) to 6.3% (at 10% level). The protein efficiency ratio did not change significantly with the inclusion of potato flour up to 8% compared to all‐wheat, but at the 10% level there was a significant reduction in this parameter (P < 0.05).
Effects of processing of grated cassava roots by the ‘screw press’ and by traditional fermentation methods on the cyanide content of gari
Authors: MADUAGWU E. N. , OBEN D. H. E.
Published: July 2010

The extent of the loss of hydrocyanic acid (HCN) from grated cassava roots, selected from both the sweet and bitter varieties, was compared in the roasted grit (gari) derived from their fresh pulp which had been dewatered and fermented by two different processes; the quick (1‐day) ‘screw press’ method (QSP) and the slow (3‐day) traditional one (STD), respectively. The relative amounts of HCN which had disappeared after 1 day, in the case of QSP, and 3 days, in respect of STD, were comparable (92–100%) for either free (non‐glycosidic) or bound (glycosidic) cyanide content of the two cultivars, indicating that the former method was more efficient than the latter in the detoxification of the grated pulp. The QSP method appeared to retain some of the bound cyanide while with the STD method, virtually no bound cyanide was detectable. About 83–91% of the total HCN content of the grated roots was present as free cyanide. It would seem that varietal differences in HCN contents of cassava may not be a critical factor in the preferential selection of the roots for ‘garification’.
Effect of metal ions such as iron and copper on the formation of nitrogen heterocyclic compounds in sesame oil—α‐amino acids model systems under frying conditions
Authors: PARIHAR D. B. , VASUNDHARA T. S. , VIJAYAYAGHAVAN P. K.
Published: July 2010

Deep‐fat frying of foods in vessels made of metals such as iron and copper imparts varied aromas. Formation of pyrazine and pyridine compounds in sesame oil and α‐amino acids model systems, with and without metallic ions such as iron and copper (10 ppm), heated under frying conditions, is reported. Metal ions have a catalytic effect on the formation of nitrogen heterocyclics and thus in changing the flavour profile.
Stability of pectins during storage
Authors: PADIVAL RAJNI A. , RANGANNA S. , MANJREKAR S. P.
Published: July 2010

Low methoxyl pectins (LMP) prepared by HCl, NaOH and NH3 deesterification procedures were stored with or without adding Na2CO3 as buffer at room temperature (25–30°C) or exposed to different relative humidities (r.h.) at 37°C. Losses of methoxyl, molecular weight and gelling power were observed in all the pectin samples. During storage, NaOH and NH3 deesterified LMP were more stable than HCl deesterified LMP with respect to gelling power. The monolayer values (Vm) of 0.5 to 0.7 g per 100 g of LMP showed that even when stored at 11% r.h., the moisture in LMP was present in the multilayer region which was conducive to methoxyl loss.

NH3 deesterified LMP precipitated at pH 0.5 and 1.5 after saponification, formed good gels similar to the LMP precipitated at pH 0.5, dried and mixed with buffer. NH3 deesterified LMP precipitated at pH 3.0 and 4.5, on the contrary, formed only coagulated gels.

The loss of gelling power of LMP during storage was due to depolymerization besides gradual transformation of increasing portions of pectinic acid molecules into pectic acid molecules. High methoxyl pectins with or without added sodium carbonate or citrate as buffer stored at 62 and 75% r.h. showed methoxyl loss. Between r.h. of < 0.1 and 49%, methoxyl loss was more in the buffered samples than in the control.
An assessment of the rapid batter expansion test for prediction of bread baking quality in New Zealand conditions
Authors: CASUTT V. J. , MEREDITH P. , MITCHELL T. A.
Published: July 2010

The rapid batter expansion test has been compared with flour protein and with test baking by a mechanical dough development method for a range of thirty‐five New Zealand wheats milled by Brabender Quadrumat Junior mill, and of fourteen commercial flours. We found no value in the test as a prediction of baking quality under our conditions.
Major volatiles in Sri Lankan arrack, a palm wine distillate
Authors: SAMARAJEEWA U. , ADAMS M. R. , ROBINSON J. M.
Published: July 2010

Arrack is a potable spirit produced in Sri Lanka by fermenting sap usually obtained from the coconut palm. In this study the major volatiles present in several commercial samples of arrack are found to be similar to those in other potable spirits although their individual concentrations differ. The variation between brands is attributed to differences in the quality of the fermented toddy used. This is thought to result from the uncontrolled and mixed nature of the fermentation. Ethyl lactate was found in all samples analysed and it is thought that production of this ester is a characteristic feature of mixed lacticalcoholic fermentations.
Occurrence of Exophiala werneckii on salted freshwater fish Osteoglossum bicirrhosum
Authors: MOK W. Y. , CASTELO F. P. , BARRETO DA SILVA M. S.
Published: July 2010

Fungal contamination occurred on the salted Amazonian fish Osteoglossum bicirrhosum which were air dried in the shade. The human pathogenic fungus Exophiala werneckii was recovered as the sole contaminant from all salted fish. It was implicated for the first time as a halophilic saprophyte causing food spoilage.
Influence of temperature and pressure on hydrogenation of low erucic acid rapeseed oil (Zephyr)
Authors: EL‐SHATTORY Y. , DEMAN L. , DEMAN J. M.
Published: July 2010

Low erucic acid rapeseed oil (Zephyr) was hydrogenated at 200, 170 and 140°C and pressure of 48 and 303 kPa. The hydrogenated oils were characterized by determination of the iodine value, trans‐isomer content, fatty acid composition, dropping point and solid fat content. From the change in iodine value and trans‐isomer content, the specific isomerization index (SII) was determined. The SII was generally lower at high pressure and low temperature. The hydrogenation reaction rate increased with temperature as well as pressure. Selectivity ratios for the hydrogenation reaction were more influenced by pressure than by temperature, the highest selectivity ratios were observed at the lower pressure.
Hydrogenation of low erucic acid rapeseed oil (Zephyr) under selective conditions
Authors: EL‐SHATTORY Y. , DEMAN L. , DEMAN J. M.
Published: July 2010

Low erucic acid rapeseed oil (Zephyr) was hydrogenated under selective conditions, 200°C, 48 kPa pressure, with 0.2% of five different commercial nickel catalysts and the standard catalyst of the American Oil Chemists’ Society. From the change in iodine value, the relative activities of the catalysts were calculated. The trans‐isomer levels were determined by infra‐red spectroscopy and the specific isomerization index calculated. Catalysts with the lowest activity resulted in the highest level of trans‐isomers. From the change in fatty composition, the selectivity ratio was calculated. Physical properties were measured by determination of dropping point and solid fat content. The commercial catalysts differed widely in their action on the hydrogenation of Zephyr oil.
Gelation property of salt soluble protein of turkey muscle as related to pH*
Authors: ANGEL S. , WEINBERG Z. G.
Published: July 2010

The gelation property of the salt soluble proteins of turkey breast and thigh plus drumstick were compared, and the proteins of the latter were found to have greater gelation capacity. The experiments were repeated on three separate occasions during which the pH level of the breast muscle was found to range from 5.8 to 5.95 while that of the leg meat ranged from 6.0 to 6.8.

It is concluded that the different gelation capacities which are apparently related to the initial pH level in the breast and leg meats, could affect palatability and should be taken into account in the development of turkey products.
A study of water activity lowering in meat during immersion‐cooking in sodium chloride‐glycerol solution. II. Kinetics of aW lowering and effect of some process variables
Authors: FAVETTO G. , CHIRIFE J. , BARTHOLOMAI G. B.
Published: July 2010

Beef slabs were dehydrated by immersion‐cooking in a sodium chloride‐glycerol solution of lower water activity (aW) in the range of temperatures 30 to 85°C. The present work studies the kinetics of aW lowering in beef as a function of various processing variables (solution temperature, sample thickness) as well as the effect of various pretreatments applied to the beef.
Cycled pressure and near‐optimal pressure policies for a freeze dryer
Authors: LITCHFIELD R. J. , LIAPIS A. I. , FARHADPOUR F. A.
Published: July 2010

The performance of a freeze dryer operating under either cyclical pressure or near‐optimal pressure control has been evaluated by numerical solution of a model describing the process.

The particular situation considered was where an interface temperature constraint prevented operation at a pressure which would minimize drying time. Comparison of the two processes showed that over the entire drying period the cycled process was marginally inferior to the near optimal scheme. Hence it appears that in industrial practice the near optimal pressure process, which requires a minimum of additional equipment, would be preferred.
Effects of blanching and sulphur dioxide on ascorbic acid and pigments of frozen capsicums
Authors: RAHMAN F. M. M. , BUCKLE K. A.
Published: July 2010

The frozen storage of capsicum tissue for 1 year at −12°C resulted in appreciable losses (from 10 to 58%) of ascorbic acid dependent upon the cultivar and the extent of tissue blanching. Ascorbic acid retention was maximal, but retention of chlorophyll a was minimal and pH dependent, in frozen blanched tissue which accordingly showed a greater increase in pheophytin formation. Sulphite treatment of unblanched tissue maintained acceptable colour through retardation of degradative interconversion and isomerization reactions of chlorophyll and carotenoid pigments during frozen storage.
Changes in fatty acids of frog legs during frozen storage
Authors: SARVADEVA A. , SRIKAR L. N.
Published: July 2010

The changes in the fatty acids of frog leg meat during frozen storage were studied with column and gas‐liquid chromatography. The major component of the lipids, the phospholipids constituted 90% of total lipids. 16:0, 18:0, 22:0 and 18:2 polyunsaturated fatty acid were the major fatty acids of the frog legs meat lipids. Short chain fatty acids were noticed to the extent of 10%. During frozen storage the proportion of phospholipids decreased, while that of neutral lipids increased. Since the total lipid content was constant, phospholipases were presumably responsible for this change. Alterations in the fatty acid composition of the neutral lipids during storage were consistent with such a hypothesis.
Isohalic sorption isotherms
Authors: DOE P. E. , HASHMI RAHILA , POULTER R. G. , OLLEY JUNE
Published: July 2010

The sorption behaviour of dried salted cod (Gadus morrhua) can be predicted from the physical properties of sodium chloride solutions and the sorption characteristics of fish muscle.
Technical note: The use of the rapid ‘catalase’ hygiene test to detect blood residues
Authors: MILLEDGE J.J.
Published: July 2010

The use of a rapid ‘catalase’ test for establishing the effectiveness of cleaning in meat processing is examined and the detection limit for blood established.
The two‐factor triangle test
Authors: HARRIES J. M. , SMITH G. L.
Published: July 2010

The triangular test, commonly used in sensory tests of food quality, is generally interpreted on the assumption that the probability of a correct selection is the same for all assessors, and independent for separate trials leading to the use of the binomial distribution in setting up tests of significance. Only when there is no real discrimination is it true that using one tasterntimes is the same as usingntasters once, the basis for the column heading ‘number of tasters or tastings’ in published tables of significance. This paper attempts to remove this assumption by the use of the beta‐binomial distribution, and suggests an interpretation in which the chance of success is different between and within assessors so that a two‐factor analysis becomes possible. A set of data relating to the flavour of fish has been reinterpreted in these terms.
Scoring methods used in the sensory analysis of foods and beverages at Long Ashton Research Station
Authors: WILLIAMS A. A.
Published: July 2010

The development of a scientific programme of research into sensory quality of fruits and beverages at Long Ashton Research Station has necessitated improvements in the evaluation methods used. It has not only meant the development of precisely defined vocabularies for describing products and methods for obtaining data from consumers, but also means of scoring the intensity of attributes. This paper describes the various scoring methods used at Long Ashton, ranging from nominal to interval and ratio, and their applicability to particular problems.
Economic study of tomato paste production
Authors: MORESI M. , LIVEROTTI C.
Published: July 2010

Statistics of tomato production and utilization have been reported to show the recent development of the tomato industry in the EEC countries. In particular, the profitability of tomato paste production has been evaluated and then analysed to assess the influence of the operating costs, EEC payments and market price of tomato paste. The economic balance for a plant capacity of 14 tons of raw tomatoes per hr and 2880 operational hr per year shows profitability of 22% in 1979 and 16% in 1980 owing to inflation and decrease in product demand. The annual cost of raw materials is not only more than 75% of production costs, but is also double the total capital invested. For this reason the tomato industry is compelled to resort to high‐interest, short‐term loans which further reduce net earnings. Mechanization of crop harvesting, automation of sorting, optimization of evaporation and packaging units and flexibility of plants are needed to maintain interest in tomato paste production in industrialized areas.
Functional properties of acetylated and succinylated sunflower protein isolate
Authors: KABIRULLAH M. , WILLS R. B. H.
Published: July 2010

Sunflower protein isolate was acylated with acetic and succinic anhydride. Succinylation changed the electrophoretic mobility, decreased the lysine and chlorogenic acid content and bulk density, increased the aqueous solubility, shifted the isoelectric point and increased the absorption, emulsification and foaming properties. Acetylation improved the functional properties of the protein to a much lesser extent. Implication of these changes is discussed with reference to food applications.
Residual cyanide concentrations during the extraction of cassava starch
Authors: ARGUEDAS PATRICIA , COOKE R. D.
Published: July 2010

Cassava starch is traditionally extracted on a small scale in many tropical countries. The process consists of wet‐milling the washed roots, washing the starch from this milled pulp on vibrating trays or in mixing tanks, sedimenting the starch in wooden canals or concrete tanks and sun‐drying the product. This process was analysed during six production runs in two factories. The distribution of cyanide followed a similar pattern in both factories. Most of the cyanogenic glucosides (bound cyanide) in the roots are converted to free cyanide during the milling operation. Between 40 and 70% of the total cyanide appears in the water used to wash the starch from the disintegrated tissue, and between 5 and 10% appears in the fibrous residue used in animal feed. This residue also contains between 12 and 23% of the starch present in the cassava. The eluted starch is allowed to sediment for 1–3 days, after which it contains less than 4% of the cyanide present in the raw material. The dried product contains less than 1% of the quantity of cyanide present in the raw material; the residual concentration is 1–5 p.p.m. The factors involved in the removal of the cyanide during starch extraction are discussed, and their importance to more efficient large‐scale processes is indicated.
Hot curing Wiltshire bacon
Authors: TAYLOR A. A. , SHAW B. G. , JOLLEY P. D. , NUTE G. R.
Published: July 2010

A process combining multi‐needle injection and dry salting of whole baconsides before they have been completely chilled can produce acceptable Wiltshire bacon in only 5 days from slaughter. Eating quality and storage stability of sliced and vacuum packed, hot cured bacon were similar to those of dry salted bacon made from conventionally chilled sides. The yields of hot cured and cold cured raw bacon were similar, but cooking yields of hams were over 3.0% higher with hot curing.

A continuous hot curing process from slaughter, through carcass preparation, multi‐needle brine injection, dry salting to chilling could simplify Wiltshire bacon processing. The concept could be particularly useful to a processor lacking the specialized facilities for traditional immersion curing.
Effect of simultaneous high intensity ultraviolet irradiation and hydrogen peroxide on bacterial spores
Authors: BAYLISS CATHERINE E. , WAITES W. M.
Published: July 2010

High intensity (1.8 × 103 mW/cm2) ultraviolet light irradiation of spores of Bacillus subtilis in the presence of 2.5% (w/v) hydrogen peroxide resulted in a rapid kill. Higher concentrations of hydrogen peroxide protected spores against the effects of irradiation. The results are discussed in relation to the use of simultaneous ultraviolet irradiation and hydrogen peroxide treatment as a method of sterilization.
An experimentally simple method for measuring diffusion in food gels
Authors: BELTON P. S. , WILSON R. H.
Published: July 2010

A simple method for measuring the diffusion coefficients of small molecules in food gels is described. The method is based on diffusion in a gel column and requires only the availability of a tube of constant cross section for the experiment. Determination of the concentration gradient in the column is made by sectioning, followed by analysis using any suitable technique. Both mutual and self‐diffusion measurements may be made. The method is used to study the diffusion of K2CrO4 in agar and agarose gels and amaranth dye in agar.