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The usefulness of an evaluation instrument is dependent on its reliability, validity, and ability to capture change. The latter psychometric characteristic is particularly important, yet is often neglected. The purpose of this study was to assess the sensitivity of a psychosocial fruit and vegetable evaluation tool for use by two US Department of Agriculture community-based programs. As part of a prospective randomized controlled trial, a sample of limited-resource women (n=93), recruited from eight counties, provided dietary recalls, behavioral assessments, and psychosocial assessments. A randomly selected sub-sample was used for venipuncture (n=55). Sensitivity of the tool was estimated using serum carotenoids, selected micronutrients, fruit/vegetable servings, and fruit/vegetable behaviors. Controlling for energy intake at baseline and change in energy intake, the change scores for the tool were correlated with reported changes in fruit and vegetable behaviors (r=0.28, P=0.01), vitamin C (r=0.25, P=0.02), and the biomarker serum carotenoids (r=0.31, P=0.02). This systematic process yielded a moderately sensitive evaluation tool useful with a limited-resource audience participating in two US Department of Agriculture programs. This is the first study to estimate sensitivity of a psychosocial tool for a fruit and vegetable intervention.

The Food and Drug Administration (FDA) has developed a new method for assessing food safety in retail establishments using a risk factor-based approach for prevention of foodborne illness. The study reported here surveyed facilities in the Navy's San Diego jurisdiction (11 fast-food and 22 full-service facilities) to establish a baseline rate of compliance with FDA risk factor categories. The Navy facility baseline-data compliance rate was compared with FDA baseline data from 1998. Fast-food facilities were less in compliance than they were in the FDA baseline data (59 percent versus 74 percent were in compliance), while full-service establishments were more in compliance than they were in the FDA baseline (73 percent versus 60 percent). The fact that compliance was greater among Navy facility full-service establishments than in the FDA national baseline may be partly due to staffing by military active-duty employees who receive incentives that may encourage compliance. The establishment of this Navy baseline allows comparison with the FDA baseline. Interventions can now be quantified., When you can measure what you are talking about and express it in numbers, you know something about it. --Lord William Thomson Kelvin (1824-1907) Introduction Quantifiable Void in Assessing the [...]

Microfluidic devices using carbon nanotube (CNT) materials (single-walled and two multiwalled (MWCNT)) for the analysis of selected analyte groups of significance in foods such as dietary antioxidants, water-soluble vitamins, vanilla favors, and isoflavones involved in representative food samples have been explored for the first time. Ultrafast separations resulted in well-defined and resolved peaks with enhanced voltammetric current in comparison with those obtained from unmodified screen-printed electrodes, turning MWCNT into an ideal material for electrochemical sensing in food analysis. Resolution was improved by a factor of 2, and sensitivity was dramatically enhanced with amplification factors toward calibration slopes from 4- to 16-fold. In both qualitative and quantitative domains, this impressive performance of CNTs integrated on microfluidics allowed solving specific challenges in food environments such as the direct detection of analytes in complex natural samples and unambiguous analytes in the control of fraud, which was not possible on nonmodified surfaces, avoiding the integration of complex preconcentration steps on these microdevices. The use of these unique materials in microfluidics for food analysis has opened new expectations in 'lab-on-a-chip' domains.

Liquid chromatography tandem mass spectrometry (LC-MS/MS) and liquid chromatography time-of-flight mass spectrometry (LC-TOFMS) are powerful and complementary techniques that can independently cover the majority of the challenges related with pesticide residue food control. The sequential combination of both systems benefits from their complementary advantages and assists to increase the performance and to simplify routine large scale pesticide multiresidue methods. The proposed approach consists of three stages: (1) automated pesticide screening by LC-TOFMS; (2) identification by LC-TOFMS accurate mass measurements; and (3) confirmation and quantitation by LC-MS/MS. We have developed a fast comprehensive (identification/confirmation + quantitation) automated screening method for 100 target pesticides in crops. In the first stage, a set of data including m/z accurate mass windows (within 20 mDa width) and retention time is obtained (using a standard solution containing all the targeted pesticides) in order to build the automated screening procedure, which is created automatically by assigning retention time and the m/z mass window for each target pesticide. Samples are then analyzed, and the method enables the screening and preliminary identification of the species first by retention time and m/z mass window, followed by subsequent identification (only if positive results) by LC-TOFMS accurate mass measurements. After that, final confirmation of the positive findings using two MRM transitions and accurate quantitation is performed by LC-MS/MS using a hybrid triple quadrupole linear ion trap (QqLIT) mass spectrometer. In addition, the use of this QqLIT instrument also offers additional advantageous scanning modes (enhanced product ion and [MS.sup.3] modes) for confirmatory purposes in compounds with poor fragmentation. Examples of applications to real samples show the potential of the proposed approach, including the detection of nonselected 'a priori' compounds as a typical case of retrospective evaluation of banned or misused substances.

The present paper describes the development and validation of a normal-phase liquid chromatography-mass spectrometry (NP-HPLC-MS) method for the screening and quantification of vitamin E constituents in human plasma and food matrixes. Liquid-liquid extraction combined with isotope dilution was applied to extract the lipophilic target analytes. Baseline separation of ([alpha]-tocopherylacetate, [alpha]-tocopherol, [alpha]-tocotrienol, [alpha]-tocopherylquinone, [beta]-tocopherol, [gamma]-tocopheroi, [beta]-tocotrienol, [gamma]-tocotrienol, [delta]-tocopherol, and [delta]-tocotrienol was achieved utilizing a normal-phase amine column operated with n-hexane and 1,4-dioxane as solvents. Detection was achieved by positive-ion atmospheric-pressure chemical ionization (APCI). Key features of the method are lower limits of detection, 3-51 nmoles/L; lower limits of quantification, 8-168 nmoles/L; linearity coefficients, 0.9778-0.9989; linear ranges, 0.01-29/[micro]mol/L; recoveries, 53-92%; accuracies, 99-103%; intraday precisions, 2-17%; interday precisions, 5-18%; and suppression values, 0-29%. Fragmentation of tocopherols was studied by tandem mass spectrometry, and a fragmentation scheme for tocotrienols/tocopherols is postulated. Neutral-loss and precursor-ion scan experiments were performed for targeted discovery of oxidation products of tocopherols in human blood and fish oil, the latter being an important food component. The presented data suggest that this method will help to expand the number of quantified/discovered vitamin E constituents detected in food products and analyzed during human/animal trials in order to give a more comprehensive picture to nutritionists about the fate of vitamin E.

Anteiso fatty acids (aFAs)--long-chain carboxylic acids with a methyl branch on the (n - 2)-carbon--are among the most simple fatty acids that are chiral. The most frequently occurring aFAs in food are 12-methyltetradecanoic acid (a15:0) and 14-methylhexadecanoic acid (a17:0), structures where the asymmetric carbon is more than 10 carbons separated from the polar head group. Previously, only enantioseparation of 4-methyl-substituted carboxylic fatty acids has been reported by gas chromatography. Here we present the first direct partial enantioresolution of synthesized racemic a15:0--a17:0 on a capillary column coated with 50% heptakis(6-O-tertbutyldimethylsilyl-2,3-di-O-methyl)-[beta]-cyclodextrin diluted in OV1701. Synthesized (S)-(+)-enantiomers were used to demonstrate that the elution order was (R)- prior to (S)-enantiomers. Using this system, food samples (butter, goat's milk fat, suet, human milk, seal oil, cod liver oil) known to contain aFAs were analyzed. Prior to the enantioselective gas chromatography, unsaturated fatty acids were preseparated by urea complexation, silver ion high performance liquid chromatography ([Ag.sup.+]-HPLC), or both from food samples. The fractions of the food samples enriched with methyl-branched fatty acids were then analyzed by GC/MS in the SIM mode. The measurements confirmed that the (S)-enantiomer of a15:0 (ee >96%), a16:0, and a17:0 (ee >90%, respectively) dominated in all samples. While the (R)-enantiomers could not be identified in samples from ruminants and human milk, their presence could be established in cod liver and seal oil (ee

A study describing and comparing the color, texture, taste, and aroma attributes of conventionally grown wheat and flour by using the trained panel sensory evaluation technique is presented. Results showed no differences in flavor, aroma, color attributes but the organic bread turned out to be denser in texture with smaller air cells in the appearance of crumb than conventional bread.

Role of different packaging materials in achieving the goals of packaging like, protection, preservation of food, increasing their shelf life, reduction of waste and removal of the risk of adulteration and tampering is discussed The recycling and disposal of these packaging materials done by different methods like combustion, aerobic and biodegradation can reduce the impact of waste generation on environment.

Maturity is an essential factor that determines storage-life and final quality of most fruits and vegetables. Maturity monitoring is thus of paramount importance for post-harvest handling and fruit quality regulation. Ideal analytical procedures for maturity investigation require high sensitivity, specificity, and high throughput and should be noninvasive. For the purpose of maturity differentiation, extractive electrospray ionization quadrupole time-of-flight mass spectrometry (EESI-QTOF-MS) is developed for rapid fingerprinting of compounds released from various fruits. Ripening stages of bananas, grapes, and strawberries are successfully differentiated by performing principal component analysis (PCA) of the mass spectral fingerprints of the fruits. Methodological reproducibility was also evaluated experimentally and in terms of PCA clusters. The data indicate that EESI-QTOF-MS is a useful noninvasive tool for rapid investigation and differentiation of maturity and quality of fruits without sample preparation.

The relative thermal processing time of shrimp kuruma in retortable pouches and aluminum cans are compared, and the effect of the containers on the proximate composition and quality parameters, including sensory and texture quality, are examined. Thermal processing in retortable pouches result in reduced processing time, thus beneficial to the sensory and texture quality in pouched samples, which are lighter in color, firmer and chewier in texture compared to the canned samples.

The inherent acid resistance of stationary-phase cells of Enterobacter sakazakii is determined and the possibility of increasing this resistance by acid habituation is examined. The 12 strains of the microorganism studied exhibit marked diversity in acid resistance, and the acid resistance of only some strains of Enterobacter sakazakii is enhanced by habituating the cells to an acidic environment, with no apparent relationship between the acid resistance of individual strains and their thermal resistance.

A predictive model is developed to examine the spoilage flora of a sliced cooked cured meat product to determine the specific spoilage organism (SSO), and to study the physicochemical changes of the product during storage at various temperatures. Results indicate that the developed predictive model is capable of predicting the SSO growth under isothermal and nonisothermal temperature storage conditions, predicting well the shelf life of the meat products.

The improved and more consistent whey protein coating efficiency on mechanically roughened freshly blanched- and-roasted peanuts as compared to the commercially blanched-and-roasted peanuts are investigated. Scanning electron microscope micrographs of treated peanuts confirm the effect of roughening, as also the disruption of the parenchyma cell structure of peanuts and the creation of channels that allow oil migration to the surface and subsequent formation of a waxy layer with long enough storage.

The effect of continuous pulsed electric fields (PEF) treatments on the activity of polygalacturonase (PG) enzyme in an aqueous solution of a commercial enzyme preparation are studied, while a kinetic mechanism (KM) is developed to describe and explain the experimental data. The kinetic approach is found to be highly consistent with the experimental data, with the error percentage lower than 4.4%.

A novel method was developed to detect viable and thermostable direct hemolysin (TDH) producing or TDH-related hemolysin (TRH)-producing Vibrio parahaemolyticus in seafood. The method employs two principals, one being that only viable Vibrio parahaemolyticus cells could penetrate through a soft-agar-coated filter because of their motility and the other being that DNAs released from ruptured virulent Vibrio parahaemolyticus cells into enrichment medium can be avoided by DNase pretreatment so that they do not interfere with subsequent multiplex PCR.

A three-color mixing application for food safety inspection is presented. It is shown that the chromaticness of the visual signal resulting from the three-color mixing achieved through our device is directly related to the three-band ratio of light intensity at three selected wavebands. An optical visual device using three-color mixing to implement the three-band ratio criterion is presented. Inspection through human vision assisted by an optical device that implements the three-band ratio criterion would offer flexibility and significant cost savings as compared to inspection with a multispectral machine vision system that implements the same criterion. Example applications of this optical three-color mixing technique are given for the inspection of chicken carcasses with various diseases and for apples with fecal contamination. With proper selection of the three narrow wavebands, discrimination by chromaticness that has a direct relation with the three-band ratio can work very well. In particular, compared with the previously presented two-color mixing application, the conditions of chicken carcasses were more easily identified using the three-color mixing application. The novel three-color mixing technique for visual inspection can be implemented on visual devices for a variety of applications, ranging from target detection to food safety inspection. OCIS codes: 150.0150, 120.4640, 330.1720, 330.1880.

The effect of plasticizer concentration and solvent types on shelf-life of eggs coated with chitosan solution is evaluated during 5-week storage at 25 degree Celsius. Chitosan coating increased the shelf life of eggs by at least 3 weeks compared with that of noncoated eggs.

The way in which freshness dating influences the taste acceptance of a refrigerated product is investigated. Sensory tests of 36 panelists showed freshness dating influenced the acceptability of products in a discontinuous or a nonlinear manner and it did so because it influenced perceptions of freshness and healthfulness, not of safety.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.jada.2005.07.035 Byline: Emily W. Hoffman, Verna Bergmann, Jill Armstrong Shultz, Patricia Kendall, Lydia C. Medeiros, Virginia N. Hillers Abstract: Individuals with human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome have an increased risk of contracting foodborne illnesses and need to take special precautions regarding food safety. We implemented a five-step model to assess the needs of people with HIV, develop education materials targeted to their needs, and evaluate acceptance of the materials. Needs assessment focus groups (n=8) with HIV-infected people (n=65) and interviews with health care providers (n=18) were conducted to determine motivators and barriers to adopting food safety recommendations. Education materials were developed using needs assessment data, literature on foodborne illnesses, and the Health Belief Model. Acceptability of materials was evaluated by focus groups (n=4) with HIV-infected people (n=32) and a survey of health care providers (n=25). Needs assessment focus group participants expressed resistance to and confusion about many recommendations. Prototype materials were designed to address barriers and motivators. HIV-infected people who reviewed the prototype materials in evaluation focus groups expressed positive attitudes about the materials, and most indicated willingness to follow recommendations. Health care providers were interested in distributing the education materials to their clients. Carefully listening to HIV-infected people and their health care providers, as well as detailed investigation of the literature on foodborne illnesses, contributed to acceptance of the education materials.

Abstract -- Slurry sampling followed by electrothermal vaporization (ETV) was used as sample introduction technique in inductively coupled plasma atomic emission spectrometry (ICP-AES) for the direct determination of trace elements [...]

Byline: Michael Kent (1), Jorg Oehlenschlager (2), Sabine Mierke-Klemeyer (2), Reinhard Knochel (1), Frank Daschner (1), Ove Schimmer (1) Keywords: Dielectrics; Frozen fish; Storage history; Quality Abstract: As part of an EU project (QLK1-2001-01643), the effect of storage time and temperature on the microwave dielectric properties of thawed frozen cod ( Gadus morhua) were studied. The measurements were made in the time domain, collecting the reflected pulse from the sample surface when an incident step pulse was applied through an open-ended coaxial sensor. The data were transformed using the statistical method of principal component analysis. The principal components were regressed (principal component regression) against time and temperature of storage and various sensorial variables to obtain calibration equations. These calibrations were validated using the method of internal cross-validation. Author Affiliation: (1) Christian Albrechts Universitat zu Kiel, Kiel, Germany (2) Federal Research Centre for Food and Nutrition (BFAFi), Hamburg, Germany Article History: Registration Date: 20/07/2004 Received Date: 13/04/2004 Online Date: 04/09/2004

Byline: Aristoula Karamani (1), Vassilios Triantafyllou (1), Konstantoula Akrida-Demertzi (1), Panagiotis Demertzis (1) Keywords: Food packaging materials; Chemical inertness; Test method; Refillable poly(ethylene terephthalate) bottles; Model contaminants. Abstract: The increased use of refillable poly(ethylene terephthalate) (PET) bottles as packaging for soft drinks has prompted us to investigate the effect of sorption of artificially introduced chemical contaminants into refillable PET bottles in order to establish a practical and easy-to-apply test procedure to evaluate their chemical inertness. For this evaluation, quick laboratory procedures, which focus on the interaction of PET bottle wall strips in place of actual bottles with a selection of model contaminants representing the myriad of chemicals, are proposed. The first objective of this study was to validate a modified quick chemical inertness test method for refillable bottles by comparing the results of sorption into PET strips with those of tests using actual PET bottles. A further objective was to investigate the stability of refillable PET bottles which were stored under unfavorable conditions, in relation to the chemical inertness behavior of the material. The results indicate the suitability of the modified quick test as it satisfactorily simulates contamination of refillable PET bottles. Moreover, storage of these bottles under unfavorable conditions does not have an adverse effect on the chemical inertness behavior of the plastic material. Author Affiliation: (1) Laboratory of Food Chemistry, Department of Chemistry, University of Ioannina, 45110, Ioannina, Greece Article History: Registration Date: 20/07/2004 Received Date: 23/02/2004 Online Date: 07/08/2004

Byline: Prudence N. Athearn (1), Patricia A. Kendall (1), Virginia 'Val' Hillers (2), Mary Schroeder (1), Verna Bergmann (2), Gang Chen (3), Lydia C. Medeiros (3) Keywords: pregnancy; food safety; risk awareness; motivators and barriers; focus groups Abstract: Objectives: To better understand pregnant women's food safety attitudes and beliefs that affect food selection, preparation and handling behaviors, sources of food safety information, motivators and barriers to adopting current recommendations, and preferences for receiving food safety materials. Methods: Eleven focus groups were conducted with 69 women (57 pregnant and 12 less than 6 months postpartum). The Health Belief Model guided development of the moderator's guide. In the presence of each focus group, participants completed a food safety attitude/behavior questionnaire. Sessions were audiotaped, transcribed, and analyzed for common themes across and within groups. Results: Most participants indicated moderate concern about food safety and had made some food handling or consumption changes since becoming pregnant however, many were not following 7 of the 12 specific recommendations discussed. Further, there was resistance to change habits, especially for less well-known recommendations. The women assumed their food is safe, and wanted strong evidence regarding why they should change current practices. Common barriers included lack of prior awareness of most recommendations, no prior illness from implicated foods and the convenience, perceived health benefits of, and personal preference for many risky foods discussed. Participants wanted food safety information that was quick and easy to read, sufficiently thorough, and specifically targeted to pregnant women. Conclusions: The women studied had not internalized the connection between risky food consumption during pregnancy and risk to the unborn child, but expressed interest in valid information that might cause them to change their behaviors. The information gained will be useful in developing food safety educational materials for pregnant women. Author Affiliation: (1) Department of Food Science and Human Nutrition, Colorado State University, Fort Collins, Colorado (2) Department of Food Science and Human Nutrition, Washington State University, Pullman, Washington (3) Department of Nutrition, The Ohio State University, Columbus, Ohio Article History: Registration Date: 23/09/2004

Byline: Romdhane Karoui (1), Eric Dufour (1), Laurent Pillonel (2), Daniel Picque (3), Thomas Cattenoz (3), Jacques-Olivier Bosset (2) Keywords: Emmental cheese; Authenticity; Geographic origin; Infrared; Fluorescence; Chemometry; Concatenation Abstract: A technique that used multivariate data analysis to combine mid-infrared (MIR) spectroscopy with front-face fluorescence spectroscopy was used to discriminate between Emmental cheeses originating from different European countries: Austria (n=12), Finland (n=10), Germany (n=19), France (n=57), and Switzerland (n=65). In total, 163 Emmental cheeses produced in winter (n=91) and summer (n=72) periods were investigated. When Factorial Discriminant Analysis was applied to either the infrared or fluorescence spectral data the classifications were not satisfactory. Therefore, the first twenty principal components (PCs) of the PCA extracted from each data set (MIR and tryptophan fluorescence spectra) were pooled (concatenated) into a single matrix and analysed by Factorial Discriminant Analysis. Correct classifications were obtained for the samples for 89% of the calibration spectra and 76.7% of the validation spectra. The discrimination for cheeses from Finland was excellent, while Austrian, German, French and Swiss cheeses were also discriminated well although a few samples were misclassified. It was concluded that concatenation of the data from the two spectroscopic techniques is an efficient technique for authenticating Emmental cheeses independently of their manufacturing period. Author Affiliation: (1) U.R. 'Typicite des Produits Alimentaires', ENITA de Clermont Ferrand, 63370, Lempdes, France (2) Station Federale de Recherches Laitieres de Liebefeld (FAM), CH-3003, Berne, Switzerland (3) Laboratoire de Genie et Microbiologie des Procedes Alimentaires, Institut National de la Recherche Agronomique, 78850, Thiverval Grignon, France Article History: Registration Date: 22/04/2004 Received Date: 16/01/2004 Online Date: 08/06/2004

Byline: K. O. Falade (1), I. Olukini (1), G. O. Adegoke (1) Keywords: Osmotic pretreatment; Air-drying; Pineapple slices; Heat of sorption; Adsorption isotherms. Abstract: Slabs (1 x1.5 x5 cm) of pineapple were immersed in sucrose solutions of 52degB, 60degB and 68degB (w/w) at 25 degC for 12 h. Osmosed pineapple slices were subsequently air-dried at 60 degC for 72 h. Adsorption isotherms of osmo-dried pineapple slices were determined at 20 degC and 40 degC, using the gravimetric-static method. Isotherms were modeled using Brunnauer, Emmet and Teller (BET) and Guggenheim Anderson de Boer (GAB) models. Heat of moisture adsorptions were calculated from adsorption data using the Clausius-Clapeyron equation. Adsorption isotherms of osmo-oven-dried pineapple followed the characteristic type III (J-shape) isotherms. Equilibrium moisture contents at constant water activity decreased with increasing temperature, but crossing of the isotherms occurred at a .sub.w~ 0.86. GAB and BET monolayer moisture decreased with increased temperature. The net isosteric heat increased with decreased moisture content, and decreased with increased sucrose pretreatment concentration of pineapple slices. Author Affiliation: (1) Department of Food Technology, University of Ibadan, Ibadan, Nigeria Article History: Registration Date: 13/02/2004 Received Date: 29/07/2003 Online Date: 17/03/2004

The Institute of Food Technologists' 3rd International Food Safety and Quality Conference and Expo in America attracted the world's leading experts in food technology. It provided a forum for the exchange of ideas, analysis of issues and review of the latest products and services related to food safety.

Byline: K. O. Falade (1), K. I. Adeyanju (1), P. I. Uzo-Peters (1) Abstract: Foam-mat drying of cowpea using glyceryl monostearate (GMS) and egg albumin (EG) as foaming agents was investigated. GMS and EG were incorporated into cowpea paste (22%, 25% and 28% total solids) at 2.5, 5.0, 7.5, 10.0, 12.5 and 15% (w/w), and whipped for 3, 6, 9, 12, 15, 18 and 21 min, maintaining 15, 25 and 35 degC foaming temperatures. Foam density was measured and expressed in g/cm.sup.3. Cowpea foams were dried at 60 degC (Twb, wet bulb temperature 35 degC) for 48 min. Sensory attributes of akara produced from fresh and reconstituted pastes were evaluated. Generally, foam density decreased with increased concentrations of GMS and EG in cowpea paste. Foam density decreased with decrease in total solids of cowpea paste. Minimum foam densities were obtained in cowpea foams with GMS and EG after 9 and 21 min of whipping, respectively. EG-stabilized foams were unstable for drying. Sensory evaluation showed no significant difference (P&gt 0.05, 0.01) in the quality attributes of akara produced from fresh and reconstituted GMS-stabilized cowpea powders. Author Affiliation: (1) Department of Food Technology, University of Ibadan, Ibadan, Nigeria Article History: Received Date: 31/01/2003 Online Date: 30/10/2003

Byline: Eva Hansen (1), Rikke Appelgren Trinderup (1), Marchen Hviid (2), Mianne Darre (2), Leif H. Skibsted (1) Keywords: Pressure-shift-freezing; Cryogen-freezing; Air-freezing; Pork ultra-structure; Thaw drip loss. Abstract: Drip loss from thawed, pressure-shift-frozen longissimus dorsi pork was not different from drip loss from fresh meat samples, while cryogen-frozen (using liquid nitrogen at -70 degC) and air-frozen (-20 degC) pork both had significantly higher drip loss (12%) upon thawing when compared to pressure-shift-frozen and fresh pork (4%). Pressure-shift-frozen pork was discolored, with a significant decrease in CIE redness parameter a*, and showed signs of denaturation upon visual inspection. A high molecular weight protein band (Mw 97,000) characteristic for gel electrophoresis (SDS-PAGE) for drip from fresh, air-frozen, and cryogen-frozen pork was not present in drip from pressure-shift-frozen pork. Ice crystals in the frozen pork, as evaluated by image analysis of cavities in digitized pictures from light microscopy of 14 um-thick meat slices (cut transverse to the fiber direction) embedded in tissue wax following treatment with Carnoy's fixative and ethanol, increased in the order: pressure-shift-frozen&lt cryogen-frozen&lt air-frozen pork. Meat structure, as evaluated visually following thawing, deviated from fresh meat structure only for pressure-shift-frozen pork. It is accordingly concluded that pressure denaturation of meat proteins is more important for structure appearance than growth of ice crystals, and that protein denaturation increases water-binding capacity in pressure-shift-frozen pork. Author Affiliation: (1) Food Chemistry, Department of Dairy and Food Science, Royal Veterinary and Agricultural University, Rolighedsvej 30, 1958, Frederiksberg C, Denmark (2) Danish Meat Research Institute, Maglegaardsvej 2, 4000, Roskilde, Denmark Article History: Received Date: 14/08/2003 Online Date: 07/11/2003

Byline: Nora Adanyi (1), Maria Varadi (1) Keywords: Free and total cholesterol; Amperometric detection; Organic phase biosensor; Food samples Abstract: Previous works on organic phase enzyme electrodes (OPEE) applied methods that worked mostly under stirred conditions. The aim of our present work was to develop a flow-through measuring set-up for determination of cholesterol content in organic media. For determination of free cholesterol content cholesterol oxidase (COD) was used, while for measuring the total cholesterol content a bi-enzyme cell containing immobilised cholesterol esterase (CE) and cholesterol oxidase was developed. Enzyme immobilisation took place on a natural protein membrane, by a glutaraldehyde cross-linking method, in a thin-layer enzyme cell made from Teflon. The enzyme cell was connected into a stopped-flow injection system (SFIA), with a flow-through amperometric detector. The parameters of biochemical and electrochemical reactions were measured. The effect on amperometric detection of different organic salts as electron mediator or conducting salts was studied. The optimal concentration of (TBATS) was 2.4 mg L.sup.-1 while for (FMCA) an optimal concentration was found at 0.4 mg L.sup.-1. The minimum amount of water, necessary for enzymatic activity in the organic phase, was also determined. Changing the concentration of toluene in acetonitrile carrier solution, the peaks increased definitely in the range 10--40% toluene. Since CE and COD were immobilised together in the enzyme cell, the conversion rate was found to be about 0.7--0.8 when the toluene content was higher then 30%. The linear measuring range for cholesterol oleate and cholesterol was 0.1--0.5 mM. Total cholesterol content of lard, butter and pasta samples were determined. It is concluded that an organic phase bi-enzyme cell may be suitable for cholesterol determination in food. Author Affiliation: (1) Central Food Research Institute, POB 393, 1537, Hungary Article History: Received Date: 10/06/2003 Online Date: 01/10/2003

Byline: Dirk W. Lachenmeier (1), Rainer Attig (1), Willi Frank (1), Constanze Athanasakis (1) Keywords: Identity of spirits; Vodka; Rum; Ion chromatography; Brand fraud Abstract: The use of ion chromatography to determine anions (chloride, nitrate, and sulphate) for the characterisation of colourless spirits, such as vodka or white rum, is presented. After evaporation to remove the volatiles, the sample was injected directly into the ion chromatograph. The assay showed good precision, never exceeding 1.6% RSD. The analytical results of 51 samples under study reveal that, in particular, the adulteration of brand spirits can be proven by the method described. Author Affiliation: (1) Chemisches und Veterinaruntersuchungsamt (CVUA) Karlsruhe, Weissenburger Str. 3, 76187, Karlsruhe, Germany Article History: Received Date: 14/07/2003 Online Date: 01/10/2003

Byline: Siegfried Bolenz (1), Thomas Thiessenhusen (1), Rita Schape (1) Keywords: Milk chocolate; Conch; Productivity; Rheology; Sensory analysis Abstract: The objective of the study was to shorten the conventional conching process for milk chocolate, which still takes many hours, in order to increase productivity. Due to recent findings and to progress made in raw material treatment, a hypothesis was proposed: that flavour development in the conch could be less important for milk chocolate than it certainly is for dark chocolate. Other functions of conching, like water removal and fat covering of particles, could be achieved faster by using drier raw materials and by machines applying more shear force. For the experiments, a conventional process (taking 5 hours) was condensed into 30--90 minutes. In screening trials various flake pre-drying techniques were also tested. Samples produced were analysed for particle size and flow properties, as well as by a trained sensory panel. Results from the experimental design showed best results at 60--90 minutes conching time. Probably the procedures for flake pre-drying had little or no influence under the conditions used. Verification trials compared the fast conching procedure to the standard process using two different recipes. No relevant differences in physical or sensory properties were found between samples from standard and 90-minute-fast-conching, proving that under favourable conditions conching times for milk chocolates can be drastically reduced without negative impact on product properties and perception. Author Affiliation: (1) Lebensmitteltechnologie--Food Technology, Fachhochschule Neubrandenburg--University of Applied Sciences, Brodaer Strasse 2, 17033 , Neubrandenburg, Germany Article History: Received Date: 12/05/2003 Online Date: 01/10/2003

Byline: Taner Baysal (1), Filiz Icier (1), Seda Ersus (1), Hasan YA+-ldA+-z (1) Keywords: Microwave; Infrared; Hot air; Carrot; Garlic; Drying Abstract: The effects of microwave and infrared drying on the quality of carrot and garlic were studied and compared with the effects of conventional hot air (tray drier for carrot and fluid bed drier for garlic) drying. The quality of carrot and garlic were evaluated by instrumental and sensory analysis. Rehydration, moisture content, water activity, particle density, bulk density, porosity and colour values were obtained for microwave, infrared and hot-air dried vegetables. In addition, total moisture content versus time was represented by drying rate curves of carrot and garlic samples. Finally, free moisture content versus drying rate were compared for the three different drying methods. Author Affiliation: (1) Food Engineering Department, Engineering Faculty, Ege University, Adegzmir, Turkey Article History: Received Date: 17/03/2003 Online Date: 31/10/2003

Byline: M. Dolores Selgas (1), Jesus Ros (1), M. Luisa Garcia (1) Keywords: Yeast; Dry fermented sausages; Sensory properties; Proteolysis; Lipolysis Abstract: This study examines the role of yeasts in the sensorial characteristics of dry fermented sausages. A total of 172 yeast strains were isolated from commercially obtained dry fermented sausages and their enzymatic activities studied. Those most active against meat proteins and pork fat were selected. Experimental sausages were manufactured and the yeasts inoculated onto the surface or into the mince. Control batches were manufactured similarly, but without inoculation. After ripening, the composition of the protein and lipid fractions were studied. The sensory properties of the products were evaluated by trained judges. Despite the enzymatic activity of the yeasts, the organoleptic characteristics of the sausages--irrespective of inoculation site--did not differ significantly from those of the controls. The influence of yeasts on the ripening of dry fermented sausages is, therefore, doubtful. Author Affiliation: (1) Departamento de Higiene y Tecnologia de los Alimentos, Facultad Veterinaria, Universidad Complutense, 28040, Madrid, Spain Article History: Received Date: 14/05/2003 Online Date: 01/10/2003

Byline: Radmila Milacic (1), Blaz Kralj (1) Keywords: Foodstuffs; Microwave digestion; FAAS; ETAASZn; Cu, Cd, Pb, Ni and Cr Abstract: An acid-assisted microwave digestion procedure was optimised for the determination of trace elements in foodstuffs by the use of flame and electrothermal atomic absorption spectrometric (FAAS, ETAAS) techniques. Zn, Cu, Cd, Pb, Ni and Cr were determined in cabbage, wheat, potato, instant milk, fish, eggs and baby foodstuffs. The repeatability of measurements was tested in the cabbage sample and was found to be +-3.3% for Zn, 4.6% for Cd, +-6.8% for Cu and +-15.5% for Cr. The worse value obtained for Cr was probably due to its inhomogeneous distribution and very low concentration in the cabbage. Concentrations of Ni and Pb in the cabbage sample were below the limit of detection (0.2 mg kg.sup.-1). The accuracy of the analytical procedure was checked by the analysis of the standard reference material CRM 1570 Trace and minor elements in spinach leaves and IAEA 336 Trace and minor elements in lichen. Good agreement between the certified or indicative and determined values was obtained. The results indicate that the concentrations of Zn, Cu, Cd, Pb, Ni and Cr found in cabbage, wheat and potato are comparable to the literature data. Cd, Pb and Ni were not found to be the contaminants in the foodstuffs analysed. Higher concentrations of Ni were found only in baby food 'Cokolesnik', arising from the cocoa that 'Cokolesnik' contained. It was demonstrated that the Cr content is very low in baby food, yolk and white of egg and in fish (&lt 0.05 mg kg.sup.-1 Cr). Elevated concentrations of trace elements were found only in mussels that accumulate heavy metals from the marine environment. Author Affiliation: (1) Department of Environmental Sciences, Jozef Stefan Institute, Jamova, 39, 1000, Ljubljana, Slovenia Article History: Received Date: 04/04/2003 Online Date: 20/06/2003