bluuebunny/crossref_metadata_2025 huggingface dataset:
The Emulsifying Properties of Commercial Milk Protein Products in Simple Oil‐in‐Water Emulsions and in a Model Food System
Authors: Euston S.R. , Hirst R.L
Published: July 2006

ABSTRACT: The emulsifying properties of six commercial milk protein products were studied. The products were separated into one of two groups depending on whether they contained aggregated (micellar) casein or disordered protein (casein or whey protein). Disordered proteins had a greater emulsifying ability than aggregated proteins. Dispersion of aggregated protein in dissociating buffer improved the emulsifying ability. Comparison of emulsion properties in simple oil‐in‐water emulsions with those in a model coffee whitener formulation showed that the lower emulsifying ability of aggregated protein could be partially compensated by other ingredients.
Thermal Degradation of Partially Purified Paralytic Shellfish Poison Toxins at Different Times, Temperatures, and pH
Authors: Indrasena W.M. , Gill T.A.
Published: July 2006

ABSTRACT: Mixtures of purified and partially purified paralytic shellfish poisoning (PSP) toxins including C1/2 and B1 toxins, gonyautoxins 1‐4 (GTX), neosaxitoxin (NEO), and saxitoxin (STX) were heated at different temperatures (90 to 130 °C), heating times (10 to 120 min), and pH (3 to 7) and analyzed by HPLC. C toxins declined rapidly at low pH, and GTX 1/4 toxins decreased at high temperatures and at high pH. GTX 2/3 increased initially at low pH and then declined with subsequent heating, whereas STX increased consistently at pH 3 to 4. The integrated total specific toxicity declined at high pH (6 to 7). The kinetics of thermal destruction were 1st order, and the efficacy of thermal destruction was highly dependent on pH, with rapid thermal destruction of carbamate compounds at higher pH. D values of carbamate toxins decreased with increasing temperature at high pH. Heating at low pH resulted in conversion of least toxic compounds to highly toxic compounds.
Methodology to Obtain True Thermal Conductivity of Low Porosity Food Powders
Authors: Shah K.K. , Tong C.H. , Lund D.B.
Published: July 2006

ABSTRACT: A technique was developed to measure, at a porosity close to zero, the true thermal conductivity of food powders. Samples of low porosities were prepared by mechanically compressing the food powder using a hydraulic press at pressures up to 3.035 × 105 kPa (abs) in specially designed stainless steel cylinders with a dummy probe in place. Variation in porosity of the samples was less than 5%. Thermal conductivity was measured as a function of porosity (0.086 to 0.7), moisture content (0 to 37%, dry basis), and temperature (30 to 150 °C) by the thermal conductivity probe method. The thermal conductivity values decreased with an increase in porosity and increased with an increase in moisture content and temperature.
Evaluation of Mass Transfer Mechanisms During Osmotic Treatment of Plant Materials
Authors: Rastogi N.K. , Angersbach A. , Knorr D.
Published: July 2006

ABSTRACT: The proportion of intact, damaged, and ruptured (non‐intact) cells (Zp) due to osmotic stress during osmotic treatment of potato was monitored using electrophysical measurement based on electrical impedance analysis. Osmotic stress on potato cell culture made cell membranes shrink thereby damaging the cells. The proportion of the ruptured and shrunk cells within the samples increased with the increase in concentration of solute in the osmotic solution. The osmotic removal of water from thin potato slices started at a critical osmotic pressure. Once the critical osmotic pressure was exceeded, mass transfer was rapid and the cells lost substantial amounts of water due to rupture of cell membranes.
Stability of Vitamins A, E, and B Complex in Infant Milks Claimed to have Equal Final Composition in Liquid and Powdered Form
Authors: Albalá‐Hurtado S. , Veciana‐Nogués M.T. , Vidal‐Carou M.C. , Mariné‐Font A.
Published: July 2006

ABSTRACT: Two infant milks claimed to have the same final composition in liquid and powdered form respectively were stored for 12 mo at 20, 30, and 37 °C. Vitamin E, thiamin, riboflavin, pyridoxine, folic acid, and nictoinamide remained constant at the three temperatures. However, there were statistically significant losses of vitamin A (approximately 35%) in samples stored at 37 °C. No differences were observed in vitamin stability between the two infant milks studied. Final levels of vitamin A were always higher than the minimum set by Spanish legislation. Vitamin A overfortification (approximately 200%) was more than that needed to compensate for losses during storage.
Effect of Aspartame and Fat on Sweetness Perception in Yogurt
Authors: King S.C. , Lawler P.J. , Adams J.K.
Published: July 2006

ABSTRACT: Sensory methodologies were used to measure flavor changes and perceived sweetness in yogurt made with 3 concentrations of aspartame (APM) and fat (200, 400, or 600 ppm APM and 1 or 2% fat respectively). Descriptive Analysis measures suggested that flavor changes were generally associated with changes in APM concentration. Low APM resulted in stronger sour, acid, dairy and rotten/sulfur flavors. Samples with medium and high levels of APM were stronger in fruity flavor, metallic notes, and sweetness. Time‐intensity measures suggested that APM had a greater effect than fat on sweetness aftertaste based on curve area, maximum intensity, and duration. This effect was not found in low‐level APM samples.
Supplementation of Energy‐restricted Diets with Coconut Oil Improves Nitrogen Balance Without Elevation of Blood Cholesterol Levels
Authors: Nomani M.Z.A. , Forbes B.A. , Mossahebi P. , Salaita C.G. , Loth‐Haglin M.J. , Harvey J.L. , Brooks J.L.
Published: July 2006

ABSTRACT: Thirty‐six growing male rats were fed 1 of 6 diets for 4 wk: (1) semipurified basal diet (B) with 10% corn oil, 21.6% fat calories (FC), 14 g B diet/day; (2) B + 1 g of coconut oil (32% FC); (3) B + 1 g olive oil; (4) B + 1 g corn oil; (5) B + 2.25 g starch (18.7% FC); and (6) B + 2 g coconut oil (40% FC). Weight gain and nitrogen balance were higher (p < 0.;05) for supplemented diet groups. Serum cholesterol and triglyceride levels were not different (p > 0.05). It may be suggested that under restricted energy intake conditions (67% to 75% of the requirements) a high‐fat diet (32% to 40% fat calories), including a diet rich in highly saturated coconut oil, can serve as a source of energy and contribute to improved nitrogen balance, without elevating blood cholesterol levels.
Effects of Low‐dose Gamma Irradiation and Conventional Treatments on Shelf Life and Quality Characteristics of Diced Celery
Authors: Prakash A. , Inthajak P. , Huibregtse H. , Caporaso F. , Foley D.M.
Published: July 2006

ABSTRACT: The effects of 0.5 and 1.0 kGy gamma irradiation on microbial and sensory characteristics of diced celery were compared to conventional treatments such as acidification, blanching, and chlorination. Aerobic plate counts for the irradiated celery did not exceed 107 CFU/g, in contrast, the acidified, blanched, chlorinated, and control samples surpassed aerobic microbial counts of 108 CFU/g in 22, 19, 12, and 8 d, respectively. Importantly, the 1.0‐kGy treatment eliminated inoculated Listeria monocytogenes and E. coli. While the acidified and blanched samples had significantly different sensory profiles compared to the other treatments, the irradiated samples maintained their color, texture, and aroma longer and were preferred in the sensory tests. The sensory shelf life of the 1.0‐kGy‐treated celery was 29 d compared to 22 d for the control, chlorinated, and 0.5 kGy, and 15 d for the acidified and blanched celery.
Measuring Oxidative Stability of Beef Muscles Obtained from Animals Supplemented with Vitamin E Using Conventional and Derivative Spectrophotometry
Authors: Lawlor J.B. , Sheehy P.J.A. , Kerry J.P. , Buckley D.J. , Morrissey P.A.
Published: July 2006

ABSTRACT: The measurement of oxidative stability of beef muscle, from animals fed either control or supplemented vitamin E, during refrigerated storage using both conventional and derivative spectrophotometry was examined. Lipid oxidation measured over a 7‐d period using both methods was lower in all muscles from animals fed the higher level of supplementation. Area under the curve of MDA‐TBA values obtained by derivative analysis were 68 to 80% lower in all muscles than the corresponding TBARS values obtained using conventional spectrophotometry. Overall, both methods resulted in similar patterns of oxidation. It was concluded that both methods were equally as effective in measuring the extent of lipid oxidation in beef muscle during refrigerated display.
Changes in Biogenic Amine Content of Tokaj Grapes, Wines, and Aszu‐wines
Authors: Hajós G. , Sass‐kiss A. , Szerdahelyi E. , Bardocz S.
Published: July 2006

ABSTRACT: Biogenic amines in grapes, aszu‐grapes, wines, and aszu‐wines of the Tokaj region of Hungary were separated, identified, and quantified by HPLC. The biogenic amine content of the Tokaj wines was well below the suggested limits for any of the biogenic amines. Histamine contents were especially low in all the samples investigated. The composition and concentration of the biogenic amines (polyamines) in the grape berries were altered remarkably by the Botrytis cinerea, and this resulted in a great change of the amine concentration in the aszu‐wines compared to the wines. The composition and concentration of biogenic amines might provide useful information on the vintage and can support the authentication of the Tokaj aszu‐wines.
Precursors for Formation of 2‐Pentyl Pyridine in Processing of Soybean Protein Isolates
Authors: Zhou A. , Boatright W.L.
Published: July 2006

ABSTRACT: Using stable isotopic 13C‐2,4‐decadienal and 15N‐ammonia, both compounds were confirmed as precursors in the formation of 2‐pentyl pyridine (2‐pp) in processing of soybean protein isolates (SPI). The yields of 2‐pp were higher when adding 2,4‐decadienal and ammonia together than the yields when adding 2,4‐decadienal only for soybean cultivars Stress land, LOX null, Edison, and KS4694. Arginine, lysine, asparagine, and glutamine increased 2‐pp when added together with 2,4‐decadienal, whereas aspartic acid, glutamic acid, glycine, and histidine had no effects. In both buffer and defatted soybean slurry, the highest level of 2‐pp was found at pH 9, followed by pH 7, then pH 4.5. The results indicate that the synthesis of 2‐pp may be a spontaneous reaction.
Color Stability of Edible Coatings During Prolonged Storage
Authors: Trezza T.A. , Krochta J.M.
Published: July 2006

ABSTRACT: The yellowing rates of edible coatings were determined at 23, 40, and 55 °C at 75% relative humidity (RH). Whey protein isolate (WPI) coatings had lower yellowing rates than whey protein concentrate (WPC) and the same rates as shellac coatings. Hydroxypropyl methylcellulose (HPMC) coatings had the lowest yellowing rates. Zein coatings became less yellow during storage; however, their color was still pronounced. Activation energies and Q10 values for the yellowing of whey protein coatings were similar to those previously reported for the browning of whey powder. The results indicate that WPI coatings can be used in place of shellac coatings when low‐color development is desired. WPC coatings can be used to tailor color development of a food.
Short Chain Fatty Acids Alter HEp‐2 Cell Association and Invasion by Stationary Growth Phase Salmonella Typhimurium
Authors: Durant J.A. , Lowry V.K. , Nisbet D.J. , Stanker L.H. , Corrier D.E. , Ricke S.C.
Published: July 2006

ABSTRACT: We examined the ability of stationary phase Salmonella typhimurium to adhere and invade cultured HEp‐2 cells after growth in broth supplemented with acetate, propionate, butyrate, or a mixture of the three short chain fatty acids (SCFA). At pH 6, all concentrations, except 25 and 50 mM butyrate, reduced cell‐association of S. typhimurium when compared to controls, while at pH 7 only 100 mM concentrations of acetate and butyrate reduced cell‐association significantly. Invasion percentages were greater for S. typhimurium grown at an initial pH of 6 with 25 mM acetate when compared to controls, SCFA mixture, and all other single SCFA concentration combinations. At pH 7, invasion was greater with either the SCFA mixture or 25 or 50 mM acetate than with control and all other single SCFA concentration combinations.
Changes in the Quality of Fresh‐cut Jicama in Relation to Storage Temperatures and Controlled Atmospheres
Authors: Aquino‐bolanos E.N. , Cantwell M.I. , Peiser G. , Mercado‐silva E.
Published: July 2006

ABSTRACT:Intact jicama (Pachyrhizus erosus) roots are chilling sensitive, but quality of fresh‐cut pieces (1.8 × 4.5 cm cylinders) was best maintained at low storage temperatures (0 to 5 °C). Respiration rates of different piece sizes were similar, and averaged 2, 7 and 10 μL CO2‐g−1h−1at 0 °C, 5 °C and 10 °C, respectively. Storage in air at 5 °C to 10 °C resulted in surface browning and was associated with increases in phenolics and phenylalanine ammonia lyase and polyphenol oxidase activities. High CO2atmospheres (5 to 10%) at 5 °C were very effective in retarding microbial growth and discoloration. The source of jicama root notably affected the quality and shelf‐life of the fresh‐cut pieces. Fresh‐cut pieces from stored roots (2 wk at 19 to 22 °C) had lower visual quality and crispness during subsequent storage than did pieces from recently harvested roots.
Production and Properties of Spray‐dried Amaranthus Betacyanin Pigments
Authors: Cai Y.Z. , Corke H.
Published: July 2006

ABSTRACT: Amaranthus betacyanin extracts were spray‐dried using a range of maltodextrins [10‐25 dextrose equivalent (DE)] and starches (native/modified) as carrier and coating agents at 5 inlet/outlet air temperatures and 4 feed solid contents. Higher inlet/outlet air temperatures caused greater betacyanin loss during spray drying, and affected slightly the pigment stability during storage. Adding maltodextrins and starches significantly reduced the hygroscopicity of the betacyanin extracts and enhanced storage stability. The 25 DE/10 DE mixed powders provided a longer predicted half‐life (63.6 wk) compared to the 25 DE and the 10 DE powders separately. The best dried pigment‐containing powder made was superior to commercial red beet powder in physical properties.
Irradiation in Contrast to Thermal Processing of Pepperoni for Control of Pathogens: Effects on Quality Indicators
Authors: Johnson S.C. , Sebranek J.G. , Olson D.G. , Wiegand B.R.
Published: July 2006

ABSTRACT: Differences in product quality resulting from use of irradiation or thermal processing for control of pathogens in pepperoni were investigated. Treatments consisted of irradiation doses of 1.25 kGy or 3.0 kGy, a heat treatment, and a control without heat or irradiation. Results showed that irradiating meat prior to production of dry, fermented sausage such as pepperoni, can yield products with quality indicators closely resembling those of traditional dry sausage, while still providing the required 5‐log reduction of E. coli O157:H7.
Lipid Changes of Freeze‐Dried Spinach by Various Kinds of Oxidation
Authors: Lee J. , Park K. , Lee S. , Choe E.
Published: July 2006

ABSTRACTM

: Lipid changes in freeze‐dried spinach by various oxidations were studied by using thin‐layer chromatography and gas chromatography. There were no characteristic changes in lipids by the oxidation except decrease in esterified sterols in NL and phosphatidic acid and phosphatidylcholine in PL. Stability of the freeze‐dried spinach lipid to the oxidation was higher when it was in the form of total lipid than when separated into NL, GL, or PL. Autoxidation and enzyme‐catalyzed oxidation resulted in the highest fatty‐acid composition change in NL. However, photooxidation showed the biggest change in PL and GL. C16 fatty acids tended to be more stable than C18 fatty acids to the oxidation.
Deodorization of Fish Sauce by Continuous‐Flow Extraction with Microbubbles of Supercritical Carbon Dioxide
Authors: Shimoda M. , Yamamoto Y. , Cocunubo‐Castellanos J. , Yoshimura T. , Miyake M. , Ishikawa H. , Osajima Y.
Published: July 2006

Volatiles were removed from fish sauce by continuous‐flow extraction with microbubbles of supercritical carbon dioxide. The extraction was done at 35 °C and CO2/sample flow ratio of 0.14 and 0.29 under pressures of 10 to 30 MPa. After the treatment at a CO2/sample flow ratio, 0.29 at 10 MPa, remaining percentage ((the concentration in treated sample/that in untreated one) × 100) was 5.2% trimethylamine, 8.0% S‐methyl ethanethioate, 30% dimethyldisulfide, 55 to 61% aliphatic aldehydes, and 25 to 42% carboxylic acids. The increase in CO2 flow rate improved the extraction efficiency significantly, but no effect of pressure was observed. The odor intensities of treated samples were between 1/4 and 1/8 of the untreated fish sauce.
Identification of Rodent Filth Exhibits
Authors: Zimmerman M.L. , Friedman S.L.
Published: July 2006

Three main types of rodent filth (rodent excreta pellets, gnawing, and nesting material) are described and identification procedures are listed. Suspect excreta pellets that may be encountered in foods from various animals are described in detail and presented in a dichotomous key for comparison and identification. The physical features associated with the excreta pellets (color, shape, size, weight, surface, and matrix composition) are listed for the insects and animals found in the key. Rodent gnawing and rodent nesting materials are defined and the importance of the paired incisor marks, scalloping along edges and the appearance of the building materials are described. The importance of urine, rodent excreta, hairs and/or parasites when defining nesting material, are discussed, along with the key elements used to recognize the gnawing direction by the rodents. Historical data on rodents and health/safety concerns when handling rodent filth exhibits are addressed.
Phytosterol Enrichment of Rice Bran Oil by a Supercritical Carbon Dioxide Fractionation Technique
Authors: Dunford N.T. , King J.W.
Published: July 2006

Supercritical carbon dioxide (SC–CO2) fractionation technique was evaluated as an alternative process for reducing the free‐fatty‐acid (FFA) content and minimizing the phytosterol loss of rice bran oil (RBO) during the process. The effects of pressure (20.5 to 32.0 MPa) and temperature (45 to 80 °C) for isothermal operation of the column on the composition of the resultant fractions were examined. Low‐pressure and high‐temperature conditions were found to be favorable for minimizing triglycerides (TG) and phytosterol losses during the FFA removal from crude RBO. Rice bran oil fractions with < 1% FFA, about 95% TG, and 0.35% free sterol with 1.8% oryzanol content could be obtained utilizing the described SC–CO2 fractionation technique.
Intrepretation of and Extraction of Useful Information From Irregular Fluctuating Industrial Microbial Counts
Authors: Peleg M. , Nussinovitch A. , Horowitz J.
Published: July 2006

Irregular fluctuating patterns of industrial microbial records arise because certain factors that affect them vary in a random fashion. If the counts are independent, and their series stationary with no trend or periodicity, a probabilistic model based on an asymmetric distribution function can be used to estimate the frequency of counts exceeding any given magnitude. Industrial records of standard plate counts (SPC), anaerobes, and thermophiles in 4 dairy products were characterized with the lognormal distribution. Many of the records had weak but significant autocorrelations for small lags, indicating that successive lots had similar microbial loads. Nevertheless, in almost all cases the method provided reasonable estimates of future counts frequencies, which were confirmed with fresh data.
Evaluation of Konjac Blends and Soy Protein Isolate as Fat Replacements in Low‐fat Bologna
Authors: Chin K.B. , Keeton J.T. , Miller R.K. , Longnecker M.T. , Lamkey J.W.
Published: July 2006

Low‐fat bolognas (LFB, < 2.0% fat) were developed with 2 levels (0.5% or 1.0%) of konjac blends (KB, KSS = konjac flour/starch and KNC = konjac flour/carrageenan/starch) and the replacement of meat proteins with 2% soy protein isolate (SPI, DWB). Increased levels of KB decreased (P < 0.05) lightness and yellowness, and most texture profile analysis (TPA) values. LFB containing 1.0% KB with 2% SPI addition had TPA values and sensory flavor/taste attributes similar to the control (CTL II, 30% fat), whereas LFB formulated with KSS had textural characteristics more similar to CTL II than those with KNC, based on sensory evaluation.
Biogenic Amines in Turkish Sausages (Sucuks)
Authors: ŞEnöz B. , Işikli N. , ÇOksöyler N.
Published: July 2006

In this study, Turkish fermented sausage (sucuk) samples from different producers were examined with respect to their biogenic‐amine contents, including histamine, tryptamine, and tyramine. The difference between amine levels of the samples produced through a starter‐facilitated process and those produced without using a starter was investigated. Amines were extracted from the samples using perchloric acid and analyzed by HPLC in an ODS 2 column with a UV/VIS detector at 254 nm after derivatization with dansyl chloride. Histamine and tyramine were found in all samples in the range of 6. 72 to 362. 22 and 208. 66 to 1173. 28 mg/kg, respectively. Tryptamine was detected in 15 out of 20 samples in the range of 25. 01 to 619. 11mg/kg. Statistically significant changes in amine levels of samples obtained from different producers were observed.
Diffusion of Acetic and Propionic Acids from Chitosan‐based Antimicrobial Packaging Films
Authors: Ouattara B. , Simard R.E. , Piette G. , Bégin A. , Holley R.A.
Published: July 2006

The diffusion of acetic or propionic acids from thin (44 to 54 μm) chitosan‐based antimicrobial packaging films in which they were incorporated was measured after immersion of the films in water, and the effects of pH (5.7, 6.4, or 7.0) and temperature (4 °C, 10 °C, or 24 °C) on diffusion were investigated. The kinetics of acetic‐ and propionic‐acid release deviated from the Fickian model of diffusion. Diffusion was found to be unaffected by pH in the range of values tested, but a decrease in temperature from 24 °C to 4 °C resulted in a reduction of diffusion coefficients from 2.59 × 10−12 m2.s−1 to 1.19 × 10−12 m2.s−1 for acetic acid and from 1.87 × 10−12 m2.s−1 to 0.91 × 10−12 m2.s−1 for propionic acid. The effect of temperature on diffusion was well (r2 > 0.9785) described by an Arrhenius‐type model with activation energies of 27.19 J.mole−1 (acetic) and 24.27 J.mole−1 (propionic). Incorporation of lauric acid or essential oils (cinnamaldehyde or eugenol) into the chitosan film at the time of preparation produced a subsequent reduction in the diffusion of acetic or propionic acid, and maximum effects were obtained with lauric acid and cinnamaldehyde incorporated to final concentrations of 1.0% and 0.5% (w/w), respectively.
Viscosity and Textural Attributes of Reduced‐fat Peanut Pastes
Authors: Singh S.K. , Castell‐Perez M.E. , Moreira R.G.
Published: July 2006

The viscosity and texture attributes of reduced‐fat peanut pastes (more than 50% fat reduction) using combinations of protein‐based Simplesse‐500TM (S), starch‐based PCR 352–1 (P), and water (W) were studied at 23’°C. Viscosity data were obtained for the shear rate range of 0.067s–1 to 148.9 s–1 using the Brookfield Viscometer HBDVIII with spiral adapter. Results demonstrated that two formulations produced pastes with viscosity similar to the control (reduced‐fat (30%) peanut butter): 54:5, 59.5, and 57.6 Pas at 38.2 s–1, respectively. Sensory tests showed that these pastes were lighter in color, easter to spread, less firm and grainy that the control. Results suggest the potential for development of > 50% reduced‐fat peanut pastes.
A Quantitative Process Model for Salmonella Enteritidis in Shell Eggs
Authors: Whiting R.C. , Hogue A. , Schlosser W.D. , Ebel E.D. , Morales R.A. , Baker A. , McDowell R.M.
Published: July 2006

A stochastic model estimating growth of Salmonella Enteritidis during egg collection, processing, storage, and transportation is described. The model contains equations for internal egg temperature, yolk membrane integrity, and exponential growth rate of S. Enteritidis. Monte Carlo simulations determined that no growth was likely to occur during the average 4.5 d of the egg's progression from lay through transportation. However, various time‐temperature combinations affected the subsequent abuse an egg can withstand before S. Enteritidis growth begins. Scenarios demonstrated the relative importance of ambient air temperature and indicated the greatest safety improvements in this phase for shell eggs would result from preventing unrefrigerated storage or hastening cooling immediately after lay.
Growth and Viability of Commercial Bifidobacterium spp in Skim Milk Containing Oligosaccharides and Inulin
Authors: Shin H.‐S. , Lee J.‐H. , Pestka J.J. , Ustunol Z.
Published: July 2006

Two commercial strains of Bifidobacterium spp (Bf ‐1 and Bf ‐6) were cultured in 12% (w/w) reconstituted nonfat dry milk (NDM) containing 0, 0.5, 1.0, 3.0, or 5.0% (w/v) fructooligosaccharide (FOS), galactooligosaccharide (GOS), and inulin. Inoculated samples were incubated anaerobically at 37° for 48 h. Growth and activity of the cultures in the presence of FOS, GOS, and inulin were determined. Viability of each strain was assessed after 4 weeks of refrigerated storage at 4°. Growth promotion, enhancement of activity and retention of viability were greatest when Bifidobacterium Bf‐1 and Bf‐6 were grown in the presence of FOS followed in a descending order by GOS and inulin. The effects of oligosaccharides and inulin increased with increasing carbohy drate concentration and was maximal at 5% (w/v).
Calcium Absorption in Rats Consuming Olive Oil or Sunflower Oil Unused or Used in Frying
Authors: PÉREZ‐GRANADOS A.M. , VAQUERO M.P. , NAVARRO M.P.
Published: July 2006

Olive and sunflower oils were used in repeated potato‐frying operations without turnover until the oils reached the 25% polar compound limit allowed by law. During a 28‐d period, 5 groups of rats were fed diets containing 8% of unused olive oil, olive oil used in 48 and 69 potato‐frying operations, unused sunflower oil, and sunflower oil used to fry potatoes 48 times. No significant differences in food intake, body weight, and food efficiency was observed. The 2 sunflower oil diets increased calcium absorption efficiency without modifying calcium balance, urinary calcium, blood‐serum calcium, and calcium in the carcasses. Intake of oils used in frying did not induce any significant changes. Sunflower oil enhanced calcium bioavailiability slightly, but oil used for frying did not produce any additional effect.
Feeding Tomatoes to Hamsters Reduces their Plasma Low‐density Lipoprotein Cholesterol and Triglycerides
Authors: FRIEDMAN MENDEL , FITCH T.E. , LEVIN C.E. , YOKOYAMA W.H.
Published: July 2006

Hamsters were fed semipurified diets containing green or red freeze‐dried tomato powders. Compared to the control diet devoid of tomatoes, a 59% and 44% reduction low‐density lipoprotein (LDL) cholesterol was induced by both the green and red tomatoes, respectively. The corresponding reductions in very low‐density lipoproteins (VLDL) were 45% and 35% and in plasma triglyceride concentrations 47% and 31%, respectively. Plasma levels of high‐density lipoproteins (HDL) were unaffected. Fecal deoxycholic and lithocholic acid concentrations of hamsters on tomato diets were higher than those on control diets. Possible contributions of major components of green and red tomatoes to these beneficial effects are discussed.
Flavor and Oxidative Stability of Peanut‐Sesame‐Soy Blends
Authors: SUMAINAH G.M. , SIMS C.A. , BATES R.P. , O'KEEFE S.F.
Published: July 2006

Five spreads were formulated from roasted high‐oleic acid peanuts and sesame paste (HOPS), normal‐oleic acid peanuts and sesame paste (NOPS), high‐oleic acid peanuts, sesame paste and soy (HOPSS), normal‐oleic peanuts, sesame paste and soy (NOPSS), and normal‐oleic acid peanuts only (NOP). Spreads were evaluated during 12 wk at 40 °C for sensory attributes: roast peanut, sesame, sweetness, bitterness, cardboardy, and painty. Roast peanut and sesame flavor generally decreased, and HOPSS and NOPSS had lower roasted peanut flavor. Cardboardy and painty increased in NOP, and HOPS had the lowest cardboardy and painty flavors. Peroxide values increased, with the highest value in NOP and lowest in HOPS. Sesame paste limited oxidation in products containing NOP and soy.
Postmortem Changes in Mule Duck Muscle Marinated in Red Wine
Authors: LIN Y.‐C. , CHEN W.‐T. , CHOU R.‐G.R.
Published: July 2006

Postmortem changes in duck breast muscle as affected by red wine marination at 5 °C were studied. Myofibrils were purified from the control (CON) and the red wine marinated muscle (RW) after 0, 1, 3, 7, and 14 d storage. The results showed that myofibril fragmentation index (MFI) was significantly (p < 0.05) higher in RW than in CON samples. Myosin heavy chain, α‐actinin, troponin‐T, titin, and nebulin were degraded more rapidly as seen on SDS‐PAGE in RW than in CON samples. Our results suggested that red wine marination can cause postmortem changes in mule duck breast muscle.
Liver Injury‐preventive Effect of Tea Theanine in Rats
Authors: He P. , Wada S. , Watanabe N. , Sugiyama K.
Published: July 2006

This study was conducted to isolate the constituent, which had a preventive effect on D‐galactosamine‐induced rat liver injury, from the 70% ethanol‐soluble fraction of Japanese green tea. Theanine (glutamic acid γ‐ethylamide) was identified as the active compound, and the liver injury‐preventive effect of theanine was dose‐dependent. L‐Glutamic acid γ‐ethyl ester, but not glutamine, also brought about a significantly preventive effect on liver injury when added to the diet at equimolar levels to that of 1% theanine. The results indicate that theanine is one of the effective constituents of Japanese green tea in preventing D‐galactosamine‐induced liver injury.
Purification and Characterization of Low Molecular Weight Kininogen from Pig Plasma
Authors: Lee J.‐J. , Tzeng S.‐S. , Jiang S.‐T.
Published: July 2006

A cysteine proteinase inhibitor from pig plasma with a molecular weight (MW) of 55 kDa, purified to electrophoretical homogeneity, inhibited μ‐ and m‐calpains, cathepsins B, L, and L‐like, and papain, but did not inhibit trypsin, β‐chymotrypsin, and cathepsin D. The purified inhibitor was stable at pH 3.0 to 10.5. The amounts for 50% inactivation (ID50) of papain, cathepsins B, L, and L‐like, μ‐ and m‐calpains were 10.55, 12.91, 2.18, 2.18, 30.91, and 29.27 nM, while the inhibition constant (Ki) for cathepsins B, L, L‐like, and X, and μ‐ and m‐calpains were 1.1, 0.64, 63.33, 8.19, 26, and 23.57 nM, respectively. It could inhibit the proteolysis of mackerel myosin heavy chain caused by purified cathepsin L‐like at 55 °C. Based on the MW, stability and specificity, it was identified as L‐kininogen.
Nondestructive Assessment of Lipid Oxidation in Minced Poultry Meat by Autofluorescence Spectroscopy
Authors: Wold J.P. , Mielnik M.
Published: July 2006

To develop a rapid method to assess lipid oxidation, autofluorescence spectra (excitation wavelengths 365, 380, and 400 nm) from large samples (17 cm2) of minced poultry meat were collected by an optical system to determine directly lipid oxidation level. The same samples were also measured by 2‐thiobarbituric acid method (TBARS). High correlations could be made between the TBARS method and autofluorescence spectra, especially those from 380 nm excitation. Partial least squares regression resulted in a root mean square error of 0.15 (R = 0.87) for chicken meat and 0.24 (R = 0.80) for mechanically recovered turkey meat. Classification analysis between fresh (TBARS < 0.25) and rancid (TBARS > 0.25) samples was done with high success rates. Autofluorescence spectroscopy might be well suited for rapid on‐line determination of lipid oxidation level in minced poultry meat.
Protein Extraction From Chicken Myofibrils Irrigated with Various Polyphosphate and NaCl Solutions
Authors: Xiong Y.L. , Lou X. , Wang C. , Moody W.G. , Harmon R.J.
Published: July 2006

Physical changes in chicken gastrocnemius myofibrils incubated in 0.1 to 1.0 M NaCl solutions with or without 10 mM ortho‐(P), pyro‐(PP), tripoly‐(TPP) or hexameta‐ (HMP) phosphate at pH 6.0 were examined by phase‐contrast microscopy, electrophoresis, and solubility. PP and TPP performed similarly in promoting protein extraction, P had no apparent effect, and HMP exhibited an intermediate effect. PP, TPP, and HMP treatments markedly improved protein solubility in 0.3 and 0.4 M NaCl through the release of myosin, but the phosphate effect diminished in ≥ 0.6 M NaCl. Overall, phosphates influenced the ultrastructure of myofibrils and extraction of their constituents in the order: PP ∼ TPP > HMP > P ∼ nonphosphate control.
Study of Caking in Powdered Foods Using Nuclear Magnetic Resonance Spectroscopy
Authors: Chung M.‐S. , Ruan R.R. , Chen P. , Chung S.‐H. , Ahn T.‐H. , Lee K.‐H.
Published: July 2006

Twenty‐three powdered foods and ingredients were subjected to 2 treatments: temperature scan from ‐20 to 110 °C within 2 hours, and storage at 37 °C and 55 °C for 60 d. During temperature scans, the spin‐spin relaxation time T2 values of individual samples were determined using a nuclear magnetic resonance (NMR) technique, resulting in a temperature‐T2 curve for each sample. Four typical temperature‐T2 curve patterns were identified and were found to be closely related to the physical changes in the samples, including agglomeration, water vaporization, and caking observed during temperature scans. Based on the temperature‐T2 curve patterns, the samples were classified into 4 groups each having distinguished caking behavior. In the storage tests, the samples were removed from the incubators every half an hour during first 2 d of storage period and every day afterwards. The storage test also suggests a strong relationship between molecular mobility and caking. Monitoring changes in T2 as a function of temperature provides information useful for predicting whether and when caking would occur.
Dietary Iron and Copper Removal Does Not Improve Cholesterol and Lipid Oxidative Stability of Raw and Cooked Broiler Meat
Authors: Maraschiello C. , Sárraga C. , Esteve‐García E. , Regueiro J.A. García
Published: July 2006

Thigh meat (raw and cooked) was analyzed for oxysterols, thiobarbituric acid reactive substances (TBARS), and glutathione peroxidase (GSHPx) activity in order to assess oxidative stability. The results showed that no beneficial effect was obtained by the removal of iron and copper from the animal diet. On the contrary, the oxysterol production, the TBARS, and the GSHPx activity tended to indicate a higher oxidative stress in cooked meat from the chickens deprived of iron and copper. This effect could not be explained by differences in tissue α‐tocopherol levels. Finally, correlation analyses showed that the 4 parameters studied (oxysterols, TBARS, GSHPx, α‐tocopherol) were interrelated.
Acylation and Solubility of Casein Precipitated by Carbon Dioxide
Authors: Santos C.V. , Tomasula P.M.
Published: July 2006

Casein precipitated from milk using carbon dioxide (CO2‐casein) and calcium caseinate were acetylated and succinylated. Aqueous solubility of casein was measured at pH 3, 5, 7, and 9. Acetylation extent was lower for CO2‐casein while both succinylated to similar extents. Solubility between the unmodified caseins was similar except at pH 5 with CO2‐casein being less soluble. Succinylation enhanced solubility for both caseins at pH 5, 7, and 9 with similar solubility between the succinylated caseins at each pH. Acetylation enhanced solubility at pH 5, however CO2‐casein still possessed lower solubility than calcium caseinate. Acylation and solubility behavior indicated structural features in CO2‐casein which were not present in calcium caseinate.
Organochlorines, Organophosphates, and Pyrethroids in Channel Catfish, Rainbow Trout, and Red Swamp Crayfish from Aquaculture Facilities
Authors: Santerre C.R. , Ingram R. , Lewis G.W. , Davis J.T. , Lane L.G. , Grodner R.M. , Wei C.‐I. , Bush P.B. , Xu D.H. , Shelton J. , Alley E.G. , Hinshaw J.M.
Published: July 2006

Channel catfish (Ictalurus punctatus), rainbow trout (Oncorhynchus mykiss), and red swamp crayfish (Procambarus clarkii) were collected from 8 southern states in the United States and analyzed for 34 organochlorine, organophosphate, and pyrethroid compounds. Approximately 45% of catfish, 72% of trout, and 92% of crayfish contained no detectable residues. Most residues detected were well below action limits for fish. Chlorpyrifos, for which there is no established tolerance, was detected in catfish; however, residues of this pesticide were not detected in samples collected after the 1st year of the study. The data collected during this study further support the safety of aquaculture products.
Triose Phosphate Isomerase as an Endogenous Time‐temperature Integrator to Verify Adequacy of Roast Beef Processing
Authors: Hsu Y.C. , Sair A.I. , Booren A.M. , Smith D.M.
Published: July 2006

Bovine muscle type had a large influence on the initial activity and heat stability of triose phosphate isomerase (TPI). TPI activity in the round muscles was more heat labile than in the chuck muscles. Residual TPI activity in bovine semimembranosus muscle was determined after cooking using adequate and corresponding inadequate U.S. Department of Agriculture processing schedules. In both water bath and pilot oven studies, TPI activity was similar in adequately processed beef (about 2 U/g) and increased when inadequately processed by reducing the holding time by 0.5 and 1.0 log at each temperature. Taken together, these results suggested that TPI could be used as an endogenous time‐temperature indicator to verify processing adequacy of roast beef if the muscle used in the product was known.
Optimization of Simulated Ripe Olive Darkening in Presence of Manganese
Authors: Romero C. , Brenes M. , García P. , Garrido A.
Published: July 2006

Solutions of caffeic acid and hydroxytyrosol, the 2 orthodiphenols involved in ripe olive darkening, were used as model systems to optimize processing. Lineal, quadratic, and lineal interaction effects of pH and manganese content on oxidation rate of both orthodiphenols were significant. Manganese did not affect activation energy of caffeic acid oxidation but diminished that of hydroxytyrosol. Presence of manganese cations (0.34 mM) and high pH (9.0) also led to the darkest color in the 10 to 30°C temperature range but did not improve the color when added after caffeic acid and hydroxytyrosol oxidation. Results can lead to a faster oxidation period, which currently takes about a week, and darker olives.
Optimizing Preparation Conditions for Heat‐denatured Whey Protein Solutions to be Used as Cold‐gelling Ingredients
Authors: Bryant C.M. , McClements D.J.
Published: July 2006

Heat‐denatured whey protein solutions are used to make ingredients that gel at low temperatures. This study examines the influence of holding temperature (65 to 90°C), holding time (5 to 30 min), protein concentration (2 to 12 wt%) and pH (3 to 8) on the rheology and appearance of heat‐denatured whey protein solutions. The optimum preparation conditions required to produce non‐gelled transparent solutions of heat‐denatured proteins were established. The rate of cold‐gelation after the addition of 200 mM NaCl to the heat‐denatured whey protein solutions increased as their initial viscosity increased. It was possible to produce gels with different cold‐gelling characteristics by altering the thermal preparation conditions.
Synthesis of Low Molecular Weight Flavor Esters Using Plant Seedling Lipases in Organic Media
Authors: Liaquat M. , Apenten R.K. Owusu
Published: July 2006

Powders from germinated seedlings of wheat, barley, rapeseed, maize, and linola synthesized low molecular weight flavor esters in an organic medium (hexane). Direct esterification of acetic, butyric, and caproic acids, with ethanol, butanol, isopentanol, or (Z)‐3‐ hexen‐l‐ol was achieved. Of the systems examined, germinated rapeseed showed the highest degree of flavor synthesis. (Z)‐3‐hexen‐1‐yl butyrate and (Z)‐3‐hexen‐1‐yl caproate were produced with yields of about 96%. Butyl butyrate, isopentyl butyrate, butyl caproate and isopentyl caproate were produced at 80% yield. Linola seedling powder gave yields of ≤63% for ethyl acetate and butyl acetate. More moderate (40%) yields were obtained with barley and maize seedling powders. Rapeseed seedling powder is a convenient and inexpensive catalyst for preparing low molecular weight esters in organic medco.
Crystallization Kinetics of Amorphous Lactose as a Function of Moisture Content Using Isothermal Differential Scanning Calorimetry
Authors: Kedward C. J. , MacNaughtan W. , Mitchell J.R.
Published: July 2006

Isothermal differential scanning calorimetry (DSC) was used to study the crystallization kinetics of amorphous lactose at 3 moisture contents. Each sample was heated to several temperatures between Tg and Tm. After subtraction of an induction time, the Avrami equation was used to model the data and a Lauritzen‐Hoffman like expression used to fit the crystallization rates between Tg and Tm. The highest Tm/Tg ratio and crystallization rate were observed for the sample containing the most moisture. Conversely the lowest Tm/Tg ratio and crystallization rate were observed for the sample containing the least moisture. Evidence for multiple transitions was seen. The Avrami equation may not be the best way to model such data.
Bioactive Properties of Wild Blueberry Fruits
Authors: Smith M.A.L. , Marley K.A. , Seigler D. , Singletary K.W. , Meline B.
Published: July 2006

Bioactive extracts from wild blueberries were isolated, fractionated, and analyzed. Antioxidant activity, cardioprotective capacity, and ability to inhibit the initiation stage of chemically‐induced carcinogenesis were evaluated. Many fractions had antioxidant activity, especially those rich in anthocyanins and proanthocyanidins. The ease of isolation of bioactive compounds and the ability to obtain accurate bioassays depended strongly on the source material used. Extracts from spray‐dried formulations containing magnesium citrate and tri‐calcium phosphate provided easier materials for bioactivity assessment and demonstrated antioxidant, cancer preventive and cardioprotective activity. Extracts with potent antioxidant activity degraded readily, underscoring the need for rapid alternative fractionation tactics and rigorously controlled storage conditions.
Involvement of Disulfide Bonds in Bovine β‐Lactoglobulin B Gels Set Thermally at Various pH
Authors: Otte J. , Zakora M. , Qvist K.B.
Published: July 2006

To obtain information on forces important for maintenance of the structure of heat‐set β‐lactoglobulin gels, gels set from pure β‐lactoglobulin at pH 3.0, 5.0, and 7.0 were solubilized in dissociating buffers, and solubilized material was characterized by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) and size exclusion high performance liquid chromatography. The gel formed at pH 7.0 was largely soluble in urea (or SDS), and this gel seemed to be built from covalently linked soluble aggregates, associating into a gel network mainly by strong noncovalent interactions. The gel set at pH 5.0 was solubilized only in the presence of a reducing agent, indicating that this gel structure was supported mainly by covalent disulfide bonds. The gel set at pH 3.0 was almost completely solubilized in SDS or urea without a reducing agent, showing the importance of noncovalent interactions in maintaining the gel structure.
Anthocyanins, Phenolics, and Antioxidant Capacity of Processed Lowbush Blueberry Products
Authors: Kalt W. , McDonald J.E. , Donner H.
Published: July 2006

Temperature, pH, and oxygenation of extracted blueberries were examined to determine how processing may affect the antioxidant capacity of blueberry food products. Extraction of fruit at 60 °C resulted in higher recovery of anthocyanins and antioxidant capacity, compared to extracts obtained at 25 °C. Subsequent room temperature storage resulted in losses in anthocyanins and antioxidant capacity only in those extracts obtained at 60 °C. Antioxidant capacity was greatest in pH 1 extracts, compared to extracts at pH 4 and 7. Oxygenation was detrimental to both anthocyanins and antioxidant capacity. Antioxidant capacity of processed products was positively correlated with anthocyanin (R = 0.92) and phenolic content (R = 0.95), and negatively correlated with % polymeric color (R = ‐0.64). In general, products that had experienced less processing had a higher antioxidant capacity. Simple colorimetric tests for anthocyanins and phenolics proved to be useful indicators of antioxidant capacity in processed products.
Mathematical Evaluation of Effective Moisture Diffusivity in Fresh Japanese Noodles (Udon) by Regular Regime Theory
Authors: Inazu T. , Iwasaki K.
Published: July 2006

The effect of moisture content and temperature on the effective moisture diffusivity was investigated to have the optimal drying condition of Japanese noodles (Udon) using regular regime theory. The drying of fresh Udon of different moisture contents was carried out under constant conditions of relative humidity and airflow at 20, 30, and 40 °C. The existence of regular regime periods for fresh noodles was experimentally verified. Effective moisture diffusivity obtained ranged from 2.1 × 10 ‐7 to 3.7 × 10 ‐7 cm2 s‐1. The effect of temperature on effective moisture diffusivity was adequately modeled by the Arrhenius relationship, although the effect of moisture content was quite small.
Influence of Carotenoids and Pulps on the Color Modification of Blood Orange Juice
Authors: Arena E. , Fallico B. , Maccarone E.
Published: July 2006

The causes of color modification in blood orange juice due to the heating concentration process were investigated. A Not From Concentrate (NFC) juice and a Reconstituted From Concentrated (RFC) juice, arising from the same stock of pigmented oranges, appeared very different in color although they had the same content of anthocyanins. CIE (Commision Internationale des Enclarages)‐Lab measurements showed a slight decrease of L* and a* values and a very large increase of b* and hue values in RFC juice. Different distribution of carotenoids between serum and pulps and modification of pulp size appeared to be responsible for color modification.
Factors Limiting the Efficacy of Hydrogen Peroxide Washes for Decontamination of Apples Containing Escherichia coli
Authors: Sapers G.M. , Miller R.L. , Jantschke M. , Mattrazzo A.M.
Published: July 2006

Factors limiting efficacy of H2O2 washes and alternative decontamination strategies were investigated with Golden Delicious apples, inoculated with nonpathogenic Escherichia coli. Post‐treatment rinsing decreased efficacy by eliminating residual H2O2. A 2‐stage wash incorporating a rinse to remove surfactant residues prior to H2O2 application was developed. Rapid attachment of E. coli to apples prevented effective removal by washing with water. Surviving E. coli following a 5% H2O2 wash were concentrated in stem and calyx areas. Survival was independent of the time interval between inoculation and washing. E. coli inoculation of punctured apple surfaces resulted in growth at 20 °C and greater survival after washing with 5% H2O2. Improved decontamination methods are needed.
Sensory and Nutritive Qualities of Food
Authors: Lee Tung‐Ching
Published: July 2006

Coverage of original research on flavor, color, and texture assessment, both quantitative and subjective; nutritional properties; nutraceuticals; and quality attributes as influenced by processing/storage/packagingf