bluuebunny/crossref_metadata_2025 huggingface dataset:
Proteolysis of αs1‐Casein by Papain in a Complex Environment. Influence of Ionic Strength on the Kinetic Constants
Authors: SANOGO T. , PAQUET D. , LINDEN G.
Published: August 2006

The influence of αs1‐casein concentration on the hydrolytic activity of papain was studied. High substrate concentration was inhibitory. In presence of NaCl, the papain affinity for αs1‐casein increased (the apparent Michaelis constant (Km. app.) decreased from 9.4 10−5 to 5.6 10−5 M) and was lower for 0.08M NaCl. The maximum velocity (Vmax app‐) was independant from NaCl concentration below 0.34M but decreased above. The enzyme‐substrate affinity was increased by the addition of urea, but the Vmax app. decreased. The inhibitory effect of excess substrate was more important with the presence of both urea and NaCl. Acetylation of αs1‐casein showed that Km. app. (21.2 10−5M) was independant of salt concentration, while the Vmax app. varied, and the substrate inhibitory activity was suppressed.
The Leidenfrost Phenomenon: Experimental Investigation of the Vaporization of Nitrogen Droplets on a Food Surface
Authors: AWONORIN S. O. , LAMB J.
Published: August 2006

The vaporization of liquid nitrogen droplets at rest on a gelatin slab of food material was investigated in relation to heat transfer in food freezing. Measurements were made of changes in droplet sizes during evaporation using a photographic technique while varying the slab surface temperature from + 10°C to ‐ 120°C at atmospheric pressure. The measured values of the vaporization time were about 12% higher than those theoretically predicted, and about 15% lower for droplets contaminated with moisture.
Crystallization Kinetics of Alpha‐Lactose Monohydrate in a Continuous Cooling Crystallizer
Authors: SHI Y. , LIANG B. , HARTEL R. W.
Published: August 2006

The crystallization of alpha‐lactose monohydrate in a continuous cooling crystallizer was investigated at various temperatures and super‐saturations. The population balance model was used to analyze the product crystal size distribution as determined by the Coulter Multi‐Sizer for each condition studied. Nucleation and growth values were thereby determined for each temperature and supersaturation. Kinetic models were then developed for both nucleation and growth to demonstrate the effects of the operating parameters. The results showed that the nucleation process had a temperature dependence with an activation energy of 17.0 kcal/mole and that nucleation increased with the 1.9 power of supersaturation and the 1.0 power of the suspension density (mass of crystals). The growth process was found to have a temperature dependence with an activation energy of 22.1 kcal/mole and to be a second order function of the supersaturation.
Replacement of Carbon‐refined Corn Syrups with Ion‐exchanged Corn Syrups in Ice Cream Formulations
Authors: GOFF H. D. , McCURDY R. D. , GULLETT E. A.
Published: August 2006

Ice cream was manufactured utilizing ten corn syrups at 5% (dry basis) in the mix, 30 DE, 42 DE, 42 DE high maltose (HM), 55 DE HM and 64 DE, each of which was processed through the carbon‐refined and ion‐exchanged processes. An increase in DE of the syrup led to a decrease in mix viscosity, a decrease in the freezing point of the mix, a decrease in fat destabilization and a decrease in firmness of the ice cream. The ion‐exchanged syrups decreased the mix viscosity and produced a drier ice cream with greater fat destabilization but had no influence on mix freezing point depression, overrun, firmness or meltdown. Sensory results from the 42DE HM and 55DE HM carbon‐refined and ion‐exchanged products evaluated in this study showed no differences in sweetness or texture. The flavor and acceptability of 42DE HM carbon‐refined syrup in ice cream was preferred less than the 42DE HM or 55DE HM ion‐exchanged syrups.
Potassium Sorbate Permeability of Methylcellulose and Hydroxypropyl Methylcellulose Coatings: Effect of Fatty Acids
Authors: VOJDANI FAKHRIEH , TORRES J. ANTONIO
Published: August 2006

Surface microbial stability is a major determinant of the shelf life of refrigerated meat products. Surface microbial growth has also been noticed in intermediate moisture foods exposed to temperature fluctuations. One solution to this problem is to apply edible coatings to the food surface which control diffusion of antimicrobial agents into the food. Films with such properties were identified using a permeability cell. Methyl‐ and hydroxypropyl methylcellulose mixed with lauric, palmitic, stearic and arachidic acid significantly lowered the potassium sorbate permeation rate relative to cellulose ether films containing no fatty acids. Permeability determinations at 5, 24, 32 and 40°C showed excellent agreement with the Arrhenius activation energy model for the permeation process.
Effects of Lactic Acid on Epimysial Connective Tissues of Muscles Used for Restructured Beef Steaks
Authors: WHITING R. C. , STRANGE E. D.
Published: August 2006

Isolated strips of epimysium from beef forequarter muscles were treated with several acids and other chemicals to degrade the connective tissue. Lactic acid significantly reduced the shear force to penetrate the strips. Muscles were excised intact from beef clod, immersed in 0.5M lactic acid for 30 min at 23°C diced and restructured into steaks. This significantly decreased the amount of connective tissue, shear force values in the restructured steaks, and water binding compared to steaks made from untrimmed muscles.
Analysis of Volatiles Related to Warmed over Flavor of Cooked Chevon
Authors: LAMIKANRA VERIAN T. , DUPUY HAROLD P.
Published: August 2006

The development of warmed over flavor (WOF) in cooked chevon was monitored from its Tenax trapped volatiles by direct gas chromatography (GC). WOF markers, pentanal, hexanal, heptanal, 2,‐3‐octanedione and nonanal were identified from volatile profiles obtained with packed poly MPE coated Tenax‐GC column. These volatile markers as well as the total volatiles increased over 6 days storage of cooked chevon at 4°C. Increase in hexanal was more rapid than the other WOF markers. Results suggest WOF development in cooked chevon is more rapid than reported rates for other cooked meats.
Thiamin Retention and Other Characteristics of Cooked Beef Loin Roasts
Authors: COOKSEY K. , KLEIN B. P. , McKEITH F. K.
Published: August 2006

Beef loin roasts were prepared by three procedures that simulated home, foodservice or commercial methods for precooking meat prior to vacuum packaging. Roasts were prepared by conventional electric (176.5°C), cook‐in‐package waterbath (70°C water), or smokehouse (ambient temperature) heating. Yield, thiamin, fat, water content, and Instron tenderness of roasts were determined. Raw roasts had higher (P<0.05) water and free water content. All cooked roasts were significantly lower in thiamin content (dry, fat free basis) and thiamin retention (true and dry, fat free basis) than raw roasts (P<0.05). No differences were observed between cooking procedures evaluated (P>0.05), suggesting that most heat processing treatments used for precooking packaged meat result in similar quality products.
Selective Inhibition of Lectin Induced Rabbit Erythrocyte Agglutination by Hydrolysates of Skeletal Beef Protein
Authors: MEDINA M. B.
Published: August 2006

Soybean lectin (SBL) induced agglutination of rabbit red blood cells (RRBC) was selectively inhibited by partial tryptic hydrolysates of beef protein isolate and all‐beef frankfurter. These interactions have been utilized to design a noninstrumental agglutination method to detect nonbeef muscle protein in meat products. The presence of non‐beef muscle proteins in cooked sausages is reflected by a reduced level of inhibition established for the all‐beef skeletal muscle hydrolysate. The method effectively detected the presence of 10‐50% non‐beef proteins (soya, pork, pork rind, chicken, turkey and surimi) substituted in all‐beef frankfurter.
Polymers Decrease Cleaning Time of an Ultrafiltration Membrane Fouled with Pectin
Authors: TZENG;and WEN C. , ZALL ROBERT R.
Published: August 2006

An ultrafiltration system fouled by pectin solutions was used as a model system. The fouled membrane flux was fully restored by circulating 0.5% NaOH solution for 1 hr. By adding 0.003% polyethylene oxide) in 0.5% NaOH solution, the cleaning time required to fully recover flux of the fouled membrane was reduced to 2 min. The mechanism of improving cleaning efficiency may not be wholly attributed to the scouring effect of the polymer on the membrane surface. The cleaning and rinsing results suggest that polymers in cleaning solutions convert the pectin foulant into a foulant‐polymer complex which could be readily rinsed from the membrane surface by water.
Improved Diazotization‐coupling Technique for Analysis of Methyl Anthranilate in Grape Products
Authors: EKANAYAKE ATHULA , SMITH R. STEVEN , NELSON PHILIP E.
Published: August 2006

Methyl anthranilate was determined in grape products by diazotizing with 1M HC1 and 1% sodium nitrite and coupling the diazonium salt with N‐1‐naphthylethylenediamine dihydrochloride in situ. The chromophore which formed had an extinction coefficient of 42,000 mole−1L cm−1 and color formation correlated with concentration in accordance with Beer's Law up to about 100 μg methyl anthranilate. Grape essence samples with 3 to 124 μg mL−1 methyl anthranilate were used to evaluate the method against a gas chromatographic technique. The correlation coefficient was >0.99 between the two methods. Compared with existing methods, this new method has the advantage of not requiring stringent reaction times or conditions.
Effect of Animal Age on the Tenderness of Selected Beef Muscles
Authors: SHORTHOSE W.R. , HARRIS P.V.
Published: August 2006

The tenderness of 12 beef muscles from animals of 8 different age groups (ranging from 1 to about 60 months old) which were treated to minimize pre‐rigor myofibrillar shortening, have been assessed using objective and subjective methods. The mean tenderness of these 12 muscles significantly (p<0.001) decreased with age. The rate of increase in the toughness of individual muscles with animal age was related to their connective tissue strength. Psoas major muscles were almost unaffected by increasing animal age whereas high connective tissue strength muscles, such as the Biceps femoris, trebled in toughness. A comparison of the different muscles revealed that one of the least representative was the often used M. longissimus dorsi.
Lipid Oxidation in Chicken Muscles and Skin After Roasting and Refrigerated Storage of Main Broiler Parts
Authors: PIKUL JAN , KUMMEROW FRED A.
Published: August 2006

The muscles and attached skin of fresh chicken broiler parts, which were roasted in a convection oven and subsequently kept at 4°C for 4 days were analyzed for lipid oxidation products (LOP). Roasting and refrigerated storage significantly increased the amount of malonaldehyde which occurred faster in the skin than in the muscles. Also, after roasting, lipid oxidation fluorescence products increased in the aqueous phase and, after refrigerated storage, in the organic phase of Folch extracted muscles and skin. The lowest concentration of LOP was found in roasted, separated parts of broilers, especially in the drumsticks and wings as opposed to roasted carcass halves or quarters. The absolute amount of LOP in muscles and skin after roasting was a result of initial concentrations of LOP in raw samples and the type of roasted broiler parts.
Bacterial Growth and Histamine Production on Vacuum Packaged Tuna
Authors: WEI C.I. , CHEN C.‐M. , KOBURGER J. A. , OTWELL W. S. , MARSHALL M. R.
Published: August 2006

Vacuum and nonvacuum packaged samples of tuna or tuna spiked with Klebsiella oxytoca T2, Morganella morganii JM or Hafnia alvei T8 were stored at 2°C and 10°C and examined for bacterial growth and histamine production on day 3, 6, 10 and 15. Unlike those stored at 2°C, tuna samples stored at 100°C showed significant bacterial growth over time and had high levels of histamine (>200 mg/100g tuna on day 15). Vacuum packaging did not show any beneficial effect in controlling bacterial growth and histamine production on tuna samples at these two temperatures. Low temperature storage was more effective than vacuum packaging in controlling histamine production by the bacteria tested.
Effects of Vacuum Packaging, Glazing, and Erythorbic Acid on the Shelf‐Life of Frozen White Hake and Mackerel
Authors: SANTOS E.E.M. , REGENSTEIN J.M.
Published: August 2006

The quality changes during frozen storage of two underutilized species of fish: mackerel (Scomber scombrus), a fatty species, and white hake (Urophycis tenuis) a nonfatty, gadoid species, with or without a bag, vacuum, and/or erythorbic acid, were measured using the dimethy‐lamine (DMA) test for hake and the thiobarbituric acid (TBA) test for mackerel, and by Instron deformation, expressible moisture, thaw drip, cook loss, and sensory evaluation for both species. Texture deterioration and lipid oxidation limited the shelf‐life of hake and mackerel, respectively. Air (oxygen) prolonged the shelf‐life of hake but lessened that of mackerel. Erythorbic acid accelerated the rate of texture deterioration in hake but inhibited the rate of lipid oxidation in mackerel.
Omega‐3 Fatty Acids in Lake Superior Fish
Authors: WANG Y.J. , MILLER L.A. , PERREN M. , ADDIS P.B.
Published: August 2006

Proximate analysis and fatty acid composition of eight commercially important species of Lake Superior fish were determined. Palmitic acid (C16:0) was the predominant saturated fatty acid, accounting for 68–79% of total saturated acids. Oleic acid (C18:1) was the most abundant monounsaturated fatty acid. Linoleic acid (C18:2), linolenic acid (C18:3), eicosapentaenoic acid (C20:5) and docosahexaenoic acid (C22:6) were the predominant polyunsaturated fatty acids. Brining, smoking and refrigerated storage caused a reduction in total lipid, but only a small loss in n‐3 fatty acids. The data revealed that most Lake Superior fish examined were excellent sources of polyunsaturated fatty acids with very high levels of omega‐3 (n‐3) fatty acids, especially eicosapentaenoic and docosahexaenoic acids.
Simultaneous Determination by HPLC of Fat‐Soluble Vitamins in Albacore (Thunnus alalunga)
Authors: POZO R. G. , SAITUA E. S. , UNCILLA I. , MONTOYA J.A.
Published: August 2006

The fat‐soluble vitamins A, D and E were determined by a liquid chromatographic method. The vitamins were extracted from the tissues with chloroform and methanol, saponified and separated on a Lichrosorb normal phase column followed by UV detection. Recoveries of added vitamins in liver samples were 93.0% for vitamin A, 90.0% for vitamin D and 92.1% for vitamin E. The results from a study of fat‐soluble vitamins in samples of albacore showed that the vitamin A and D were found only in fish liver and vitamin E was found in the liver and the edible muscle.
Yield and Composition of Surimi from Pacific Whiting (Merluccius productus) and the Effect of Various Protein Additives on Gel Strength
Authors: CHANG‐LEE M.V. , LAMPILA L.E. , CRAWFORD D.L.
Published: August 2006

Based on round fish weight, the yields from processing Pacific whiting into surimi included 43.3% planks, 36.2% minced flesh, 23.8% washed and pressed flesh, 19.5% refined flesh and 21.4% surimi (91.7% refined flesh plus 8.3% cryoprotectants). After washing (3:1; watenminced flesh) and pressing twice, 40.6% of the original lipid and 77.4% of the original ash were removed from the minced flesh. Surimi contained 54% extractable myofibrillar protein. Egg white (EW), whey protein concentrate and soy protein isolate at 0 to 5.0% levels were evaluated as protein additives to heat‐set gels. EW, at the 3.0% level produced superior gel hardness and elasticity (P≤0.05).
Effect of Powdered Cellulose on the Texture and Freeze‐thaw Stability of Surimi‐based Shellfish Analog Products
Authors: YOON K.S. , LEE C.M.
Published: August 2006

The cryoprotective property in surimi and the texture‐modifying and freeze‐thaw stabilizing properties in molded (shrimp‐type) and fiberized (crab leg‐type) products of powdered cellulose were studied using Instron testing and sensory evaluation. Particle size, level and manner of incorporation of cellulose with varying combinations of modified starch of sorbitol/sucrose were the main parameters studied. In both molded and fiberized products, compressive force (cohesiveness) and penetration/shear force (firmness) decreased with an increased concentration of cellulose. Cellulose significantly modified texture at 2% by reducing the increase in firmness after freeze‐thaw cycles. Substitution of 2% cellulose for modified starch in surimi‐based products or for cryoprotectants in surimi did not alter freeze‐thaw stability.
Oxidative Stability of Cholesterol‐Free Egg Lipid Fractions
Authors: BLACKWELDER J.A. , PIKE O.A.
Published: August 2006

Lipids were extracted from fresh egg yolk using hexane:isopropanol (3:2.v/v) and separated on a silicic acid column into triacylglycerol (TG), phospholipid (PL), cholesteryl ester and cholesterol fractions using hexane, ethyl acetate and methanol. TG and PL fractions were cholesterol‐free. Oxidative stability at 35° C of crude lipids, TG, PL and combined TG + PL was evaluated over 12 days by measuring conjugated dienes, conjugated trienes and thiobarbituric acid reactive substances. PL and TG exhibited significantly higher oxidation than the crude lipids (alpha = 0.01). Combined TG + PL was not significantly different than the crude lipids (alpha = 0.01), showing much higher stability than individual TG or PL fractions.
Changes in Numbers and Kinds of Lactic Acid Bacteria During Ripening of Kefalotyri Cheese
Authors: LITOPOULOU‐TZANETAKI E.
Published: August 2006

Changes in lactic acid bacteria in ripening Kefalotyri cheese were studied. Throughout ripening lactobacilli and enterococci counts were high (lactobacilli 106‐109/g, enterococci 104‐107/g). Leuconostocs, lactic streptococci and betabacteria disappeared early in ripening. Leuconostoc lactis and Streptococcus thermophilus prevailed intitially (23% and 13%, respectively). Enterococcus faecium, Lactobacillus casei and L. plantarum became predominant with ripening. After 4 months ripening, E. faecium were dominant (35.5%) followed by L. plantarum (18.4%) and L. casei subsp. casei (15.8%). Results suggested that a starter consisting of both lactic acid bacteria that disappeared early and lactic acid bacteria that survived throughout ripening should be preferable for the production of Kefalotyri cheese.
Sensory Evaluation of Tempeh Produced by Fermentation of Common Beans
Authors: PAREDES‐LÓPEZ O. , HARRY G.I. , GONZALEZ‐CASTAÑEDA J.
Published: August 2006

A tempeh fermented product was prepared from fresh and hard‐to‐cook (HTC) common beans with the mold Rhizopus oligosporus. Fresh samples fermented for 0, 24 and 48 hr were used to prepare fried tempeh, atoles and cookies at various substitution levels. Atoles were also prepared with fermented hardened beans. A panel evaluated samples for the sensory variables: appearance, odor, color, flavor, texture, and acceptability. For fried tempeh, flavor and acceptability were the sensory variables most affected by fermentation. Atoles, supplemented with fermented fresh and HTC seeds, had significantly lower (P<0.05) flavor and color than controls, respectively. Interestingly, acceptability of atoles, from both fresh and HTC samples, and of cookies was not significantly different (P>0.05) from the controls.
Comparison of Four Different Methods for the Analysis of Dietary Fiber in Winged Bean Seeds
Authors: RAVINDRAN G. , PALMER J. K.
Published: August 2006

Two chemical and two enzymatic procedures were evaluated with respect to efficiency of protein removal and consistency in yield and composition of soluble and insoluble dietary fiber from winged bean seeds, (cultivar TPT‐2). Considerable variability was observed in the yield and composition of the fiber fractions, but the results became more consistent when contamination of the non‐carbohydrate components (protein, ash and lignin) were accounted for in the calculations. The constituent sugars of polysaccharides were found to be similar in all four methods. Results indicated the need to critically optimize conditions to achieve efficient deproteinization and the need to differentiate “inherent” and “contaminating” protein.
Influence of Indigenous Microflora on Some Chemical Properties of Cowpea Paste
Authors: Bulgarelli M. A. , BEUCHAT L. R.
Published: August 2006

Cowpea (vigna unguiculuta) paste, the principal ingredient in akara, was evaluated to determine the influence of indigenous microflora on chemical characteristics associated with akara quality. Six formulas (with and without onion, salt and pepper), consisting of inoculated (indigenous microflora) and uninoculated pastes, were incubated for 24 hr at 30°C. A strong relationship between time of incubation and increase in titratable acidity was evident for all treatments. Nitrogen solubility and protein degradation increased during incubation. Monosaccharide content increased with incubation for all pastes, while diand oligosaccharides decreased. No significant changes in thiamin content were observed; however, riboflavin increased for all formulations as incubation progressed.
Protein and Starch Digestibility and Flatulence Potential of Germinated Cowpeas (Vigna unguiculata)
Authors: NNANNA I. A. , PHILLIPS R. DIXON
Published: August 2006

In vivo and in vitro methods with experimental rats and commercial digestive enzymes, respectively, were used in assessing the protein and starch digestibility and flatulence potential of germinated cow‐peas. Germination (24 hr at 25° or 30°C) reduced the flatulence potential of seeds (52 to 77%). In vivo digestibility of starch and protein was also significantly increase by germination. Germination did not affect in vitro protein digestibility, but reduced in vitro digestibility of freeze‐dried and 70°C‐dried starch. Cooking in boiling water significantly increased in vitro protein and starch digestibility of both ungerminated and germinated seed.
Formation of 4‐Vinyl Guaiacol in Adversely Stored Orange Juice as Measured by an Improved HPLC Method
Authors: LEE H.S. , NAGY S.
Published: August 2006

4‐Vinyl guaiacol, a potent off‐flavor compound in orange juice, was isolated by using a C‐18 cartridge and analyzed by high performance liquid chromatography (HPLC) with fluorescence detection. The new HPLC method possessed a sensitivity of 10 ppb for 4‐vinyl guaiacol and was at least 5 to 10 times more sensitive than previously reported gas‐liquid chromatographic procedures. Storage of bottled orange juice for 18 wk yielded the following 4‐vinyl guaiacol levels: 42 μg/L (20°C), 223 μ/L (30°C), and 778 μg/L (40°C). Concentration of 4‐vinyl guaiacol increased with storage time at all storage temperatures; however, a noticeable decrease occurred after extended storage at 50°C.
Comparison of Two Methods of Estimation of the Effective Moisture Diffusivity from Drying Data
Authors: KARATHANOS V. T. , VILLALOBOS G. , SARAVACOS G.D.
Published: August 2006

The effective moisture diffusivity (D) in starch materials was estimated by the method of slopes of the drying curve and a computer simulation technique. Drying data (moisture vs time) were obtained on slabs and spherical samples of hydrated and gelatinized starches in an air‐dryer operated at 60–100°C and air velocity 2 m/sec. The two methods gave similar results in high‐amylopectin starch gels of low porosity, where liquid diffusion might predominate during drying. Considerable differences between the two methods were found in hydrated granular starches and in porous high‐amylose gels, where vapor diffusion might be the main water transport mechanism.
Effects of Salt, Sugar and Screw Speed on Processing and Product Variables of Corn Meal Extruded with a Twin‐Screw Extruder
Authors: HSIEH F. , PENG I.C. , HUFF H.E.
Published: August 2006

The effects of screw speed and additives (sugar and salt) on processing and product variables of corn meal extruded with a twin‐screw extruder were studied. Higher salt (0–3%) and sugar concentrations (0–4%) in the feed decreased the die pressure, % torque and specific energy. But at 6 and 8%, sugar increased the three processing parameters. Higher screw speed (250 vs 200 rpm) decreased die pressure and % torque, but increased specific energy. The addition of salt and sugar enhanced extrudate radial and axial expansions, but reduced product bulk density and breaking strength. An increase in screw speed decreased radial expansion and bulk density, but increased axial expansion and breaking strength.
Formulation of Corn‐Based Snacks with High Nutritive Value: Biological and Sensory Evaluation
Authors: ALMEIDA‐DOMINGUEZ N.G. , VALENCIA M.E. , HIGUERA‐CIAPARA I.
Published: August 2006

Three composite flours were formulated by linear‐programming using corn, chickpea, soybean‐meal and methionine to meet the FAO/WHO pattern for lysine and sulfur amino acids. Fried snack foods were manufactured with these flours. The experimental products showed higher protein contents (18.11, 15.69, 13.16%) than a commercial corn snack used as control (7.14%). PER values of experimental snacks (2.69, 2.65, 2.54) were not statistically different from that of casein (2.77) (p>0.05). Two of the formulated products (15.69% and 13.16% protein) showed no significant differences from the control with respect to typical odor and flavor, texture and acceptability (p>0.05). These nutritionally‐improved products represent a good alternative to commercially available corn‐based snacks.
Moisture Sorption Characteristics of Kudzu Starch and Sweet Potato Starch
Authors: BOKI K. , OHNO S. , SHINODA S.
Published: August 2006

Moisture sorption characteristics of kudzu starch and sweet potato starch were investigated based on the results of moisture sorption isotherms at 11°C, 20°C and 30°C, thermal analysis, isosteric heat of sorption and entropy of sorption. The water of crystallization in sweet potato starch was strongly retained compared with that in kudzu starch. Differences in amount of moisture sorbed between kudzu starch and sweet potato starch seemed to be attributable to the stability of the microscopic structure. The interaction of moisture‐sweet potato starch was stronger than that of moisture‐kudzu starch. Amount of moisture sorbed and strength of moisture‐starch binding of the starches, preheated to 110°C, decreased compared with those of the starches vacuum‐dried at 20°C because of release of water from the amorphous part of the starch granule.
Optimized Synthesis of Sucrose Polyesters: Comparison of Physical Properties of Sucrose Polyesters, Raffinose Polyesters and Salad Oils
Authors: AKOH CASIMIR C. , SWANSON BARRY G.
Published: August 2006

Synthesis and purification of sucrose polyesters (SPE) were optimized to obtain high yields of SPE. Sucrose octaacetate (SOAC) and fatty acid methyl esters (FAME) of salad oils or FAME blends of homogenous fatty acids and salad oils were interesterified in the presence of sodium metal. Yields 99.6–99.8% of purified SPE based on initial weight of SOAC were obtained. SPE structure was confirmed by infrared (IR) and C‐13 nuclear magnetic resonance (C‐13 NMR) spectroscopy. Physical properties of SPE and raffinose polyesters (RPE) were similar to physical properties of conventional salad oils. The hydrophile‐lipophile balance (HLB) of SPE and RPE were between 2–6 HLB units. Differential scanning calorimetry (DSC) was used to determine the melting properties of SPE and RPE. Neither SPE nor RPE was susceptible to in vitro lipolysis.
Characteristics of Bovine Plasma Gels as Affected by pH Sodium Chloride, and Sodium Tripolyphosphate
Authors: KNIPE C.L. , FRYE C.B.
Published: August 2006

A model system, which simulated the pH, sodium chloride (NaCl), and alkaline phosphate (STP) levels of typical processed meat products, was used to determine the effect of NaCl, STP and pH on firmness and percent cooked yield of bovine plasma gels. Bovine plasma gel firmness increased with increasing plasma pH, whereas percent cooked yield was not affected. In contrast, when the pH, of the plasma solutions, was adjusted to a constant 5.6 to simulate the pH and buffering of meat, percent cooked yield was affected; gel firmness was not affected. With increased levels of NaCl and STP, the percent cooked plasma gel yield increased.
Association of Zinc with Soy Proteins as Affected by Heat and pH
Authors: KHAN A. , WEAVER C.M. , SATHE S.
Published: August 2006

The effect of heat on the chemical association of 65Zn with proteins and of pH on the solubility of proteins, phytic acid, zinc, and their complex formation were studied in soybeans grown hydroponically and intrinsically labeled with 65Zn. 65Zn association with soy proteins was not affected by autoclaving. Zinc was not covalently associated with the major soy proteins, 11S and 7S. Protein, phytic acid and zinc content of the raw soyflour was determined at pH range 3.5–12 before and after dialysis. pH had only a slight effect on zinc solubility. Protein‐zinc‐phytate complex formation was maximum in the pH range 7.5–10.5.
Plant Sterols in Soybean Hulls
Authors: IBRAHIM N. , PURI R.K. , KAPILA S. , UNKLESBAY N.
Published: August 2006

Using gas chromatography techniques after lipid extraction, soybean hulls were analyzed for their plant sterol components. Soybean hulls contained 7.46% and 2.02% moisture and lipid components, respectively. Three plant sterols, campestrol, stigmasterol, and β‐sitosterol, were quantified in the ratios of 1: 1.5: 2. The use of soybean hulls as food ingredients was discussed for their potential serum cholesterol reducing effects.
Effects of Heating Bacon and Sausage in Nonwoven, Melt‐blown Material
Authors: COSTELLO C.A. , MORRIS W.C. , BARWICK J.R.
Published: August 2006

Bacon and precooked sausage patties were heated in a microwave oven using a melt‐blown polypropylene pad or on paper towels. Cooking losses, percentage fat and moisture, and fatty acid profiles were determined. Sensory panelists evaluated appearance, greasiness, moistness, and chewiness. Less fat and more moisture were present in the high‐fat meats cooked in the melt‐blown pad. Higher percentages of myristic and stearic acid were found in bacon heated in paper towels. Panelists scored bacon heated in the pad as less greasy and chewy. Sausage patties heated in the pad also were scored less greasy. The use of melt‐blown material to reduce dietary fat should be explored further.
Palatability of Chilled and Frozen Beef Steaks
Authors: WHEELER T.L. , MILLER R.K. , SAVELL J.W. , CROSS H.R.
Published: August 2006

The effects of a split, split plot design, with marbling degree within USDA Choice quality grade as the whole plot, and storage system (chilled with 13 or 20 days postmortem aging or frozen with 7 or 14 days postmortem aging) and blade tenderization (once or twice) as the split plots on palatability and cooking characteristics of beef top loin (TL) and center‐cut, top sirloin (TS) steaks were determined. Marbling degree within the Choice quality grade had no effect on sensory or cooking characteristics of either steak. Storing TL steaks frozen rather than chilled adversely affected flavor intensity and cooking losses. Palatability of TS steaks was much lower than for TL steaks. These data will provide the foodservice industry with more specific guidelines for product processing specifications.
Thermal Denaturation of Perimysial Collagen in Meat Measured by Polarized Light Microscopy
Authors: SWATLAND H.J.
Published: August 2006

The feasibility of using the de Sénarmont method to study the loss of birefringence in septa of perimysium as transverse sections of meat were heated with a hot stage was shown. Samples were from beef, pork and turkey from 1 to 5 days postmortem. Although there were considerable differences between different types of samples, from 20°C to 67°C, there was generally only a slight decrease in path difference (overall mean, − 0.04 nm/°C). From 67°C to about 85°C all samples had a sharp and largely irreversible decrease in path difference (overall mean, −0.58 nm/°C) concurrent with thermal denaturation.
Effect of Breed, Sex and Tissues on Concentrations of Macrominerals in Goat Meat
Authors: PARK YOUNG W.
Published: August 2006

Macromineral concentrations in liver, Longissimus dorsi (LD) and Biceps femoris (BF) muscles of doelings and bucks from 2 breeds of goat were determined to study effects of breed, sex, tissue and their interactions on the levels of P, S, K, Ca, Mg and Na in caprine meat. Effects of breed and sex were minimal, but breed x sex interaction had significant influence on levels of K and Mg. Tissue effect was most prominant except for S content. Liver had significantly greater P, Ca and Na contents than skeletal muscles, whereas the former had slightly lower S and significantly lower K and Mg than the latter. Correlations among the levels of the minerals for the liver were different from those for the skeletal muscles.
Enzyme Activity Levels in Beef: Effect of Postmortem Aging and End‐point Cooking Temperature
Authors: SPANIER A.M. , McMILLIN K.W. , MILLER J.A.
Published: August 2006

While it is known that meat flavor varies as a function of end‐point cooking temperature, storage time, and activity of endogenous hydrolytic enzymes, little is known about the interrelationship of these three factors with flavor. Several endogenous enzymes and proteins with potential involvement in meat flavor were investigated. The data indicate two main observations: (1) enzymes are redistributed to new intracellular compartments during postmortem aging. (2) enzyme activity is temperature dependent over the range examined (20‐80°C) with some enzymes such as cathepsins B & L retaining a high level of activity (>20% of that at 20°C) at temperatures above 70°C. Thus, the combined effect of postmortem aging and cooking, via enzyme redistribution and enzyme activity, respectively, influence the production of flavor compounds and precursors.
Effects of Rigor Mortis on Gel‐forming Properties of Surimi and Unwashed Mince Prepared from Tilapia
Authors: PARK JAE W. , KORHONEN REINO W. , LANIER TYRE C.
Published: August 2006

Quality of surimi and unwashed fish (tilapia, Areochromis aureus) mince was investigated as affected by development of rigor mortis in fish prior to processing. Significantly higher protein content and yield, reduced cook loss, and enhanced gel‐forming ability and protein ex‐tractability were associated with surimi produced from pre‐rigor fish. Gels prepared from unwashed minced muscle exhibited less cook‐loss pre‐rigor, but stage of rigor had little effect on gel Theological properties and protein extractability. Thermal rigidity scanning and differential scanning calorimetry showed substantially higher rigidity values and enthalpies of denaturation, respectively, for surimi prepared from pre‐rigor fish, but no effect on transition temperatures due to stage of rigor.
Cryoprotective Effects of Lactitol, Palatinit and Polydextrose® on Cod Surimi Proteins during Frozen Storage
Authors: SYCH J. , LACROIX C. , ADAMBOUNOU L.T. , CASTAIGNE F.
Published: August 2006

The cryoprotective effects of lactitol dihydrate, Polydextrose® and Palatinit (Isomalt) at 8% w/w in codsurimi were compared to an industrial control containing a sucrose/sorbitol 1:1 mixture and a control without additive. Surimi was stored at −20°C for 12 wk and examined for freeze‐induced protein changes every 2 wk by salt extractable protein and differential scanning calorimetry analyses: Palatinit®, lactitol and Polydextrose® stabilized surimi proteins equally well as did the sucrose/sorbitol mixture. Salt extractable protein and myosin peak enthalpy for surimi were maintained at the same level as the industrial control. Confirming earlier results, initial Tmax‐myosin yielded information regarding surimi protein stability over extended periods of frozen storage.
Developing a Color Card for Raw Flesh of Astaxanthin‐fed Salmon
Authors: SKREDE GRETE , RISVIK EINAR , HUBER MARCEL , ENERSEN GRETHE , BLÜMLEIN LAURA
Published: August 2006

Color standards from the Natural Color System (NCS) were selected by a sensory panel to match color of raw flesh of astaxanthin‐fed Atlantic salmon (Salmo salar L.). The NCS notations, blackness, chromaticity and hue, of the most frequently selected standards are given. A linear relationship between average NCS hue and NCS chromaticity values of each salmon was obtained, the hue being more reddish at high color intensities. NCS chromaticity and hue were both significantly correlated with carotenoid concentration and with instrumentally obtained CIE (1976) a*, b* and hue values. Procedures for the selection of NCS standards and for the practical use of a color card in the evaluation of salmon color, were developed.
Continuous Hydrolysis of Milk Protein in a Membrane Reactor
Authors: MANNHEIM A. , CHERYAN M.
Published: August 2006

Casein was hydrolyzed using Alcalase in a continuous stirred tank membrane reactor (CSTMR) using a hollow fiber ultrafiltration membrane. A design of experiments methodology was used to optimize the four performance variables: enzyme concentration, substrate concentration, permeate flux and reactor volume. High conversion (>90%) of the casein could be achieved after one hour at 50°C and pH 8. Reactor activity was most affected by the enzyme‐to‐substrate ratio. The stability of the reactor (i.e., decay of activity with time) was a function of enzyme leakage through the membrane, thermal inactivation and enzyme‐membrane interactions.
Rennet Effects and Partitioning of Bacterial Cultures During Quarg Cheese Manufacture
Authors: SHAH N. , JELEN P. , UJVAROSY S.
Published: August 2006

Quarg was prepared with or without milk heating or rennet addition using yogurt, acidophilus, and buttermilk cultures. Total solids and protein contents in the quarg cheeses were 17.4‐34.7% and 7.4‐15.0%, respectively, depending on process conditions. Rennet addition increased the total solids content, especially when unheated milk was used; however, the corrected (18% T.S.) yield was unaffected. Yogurt culture resulted in the shortest incubation time (3.8‐4.6 hr), while the acidophilus culture alone was unsuitable. After whey separation, the concentration of bacteria from all three cultures were higher in the quarg (8.48‐9.05 log CFU/g) than in the whey (5.92‐7.90 log CFU/ g) using either centrifuge or gravity filtration methods.
Sensory Analysis of Dairy Products irradiated with Cobalt‐60 at −78°C
Authors: HASHISAKA A.E. , EINSTEIN M.A. , RASCO B.A. , HUNGATE F.P. , DONG F.M.
Published: August 2006

Sensory evaluations by healthy individuals were conducted on cobalt‐60 irradiated retail dairy products which were to be incorporated into the low microbial diets of immunosuppressed patients. Irradiation (40 kGy at ‐78°C) caused little change in product color or texture, but generally there was a decrease in overall acceptability and an increase in off‐flavor and aftertaste. Modified atmosphere packaging (nitrogen, helium, or air) or antioxidant addition (ascorbyl palmitate or a combination of butylated hydroxyanisole and butylated hydroxytoluene) prior to irradiation were effective in preserving specific sensory attributes, which in some cases resulted in improved overall acceptability (helium packed peppermint ice cream; ascorbyl palmitate treated strawberry yogurt bars) when compared to untreated irradiated products.
Effect of Carbon Dioxide Atmosphere on Staling and Water Relations in Bread
Authors: AVITAL Y. , MANNHEIM C. H. , MILTZ J.
Published: August 2006

The effect of Modified Atmosphere Packaging (MAP on staling and on water relations in bread was evaluated. Application of CO2 in MAP delayed staling of bread. Water sorption of bread packed in CO2 was reduced compared to fresh bread and to bread packed in air. A water activity of 0.75 was found to be the boundary between the multilayer and the free water range of the isotherm. Spoilage of bread (microbial growth and staling) took place only above this water activity. Inverse Gas Chromatography was found to be unsuitable for investigating the effect of CO2 on bread at the higher water activities because equilibrium conditions could not be achieved at these water activities.
Baking Properties of Bread and Cookies Incorporating Distillers' or Brewer's Grain from Wheat or Barley
Authors: RASCO B.A. , RUBENTHALER G. , BORHAN M. , DONG F.M.
Published: August 2006

The effect of granulation, level of soluble solids, and drying method on the mixing properties and baking performance of distillers’grain products from wheat in yeast‐raised breads and cookies were evaluated and compared with products containing barley spent grains (BSG). Grinding had a variable effect on baking properties. Breads containing 8% wheat distillers' grains (WDG) (no solubles) had the lowest loaf volume. Breads made with WDG and BSG had the poorest crumb grain. There were few differences observed in the mixing and baking properties of wheat distillers’grains (DDGS or DDG) regardless of whether the materials were dried by harsh (steam tube, tunnel) or milder (atmospheric drum) drying treatments.
Composition of Fermented Grape Juice Continuously Produced by Immobilized Lactobacillus casei
Authors: TAKAGI KAYOKO , TOYODA MASATAKE , SAITO YUKIO , NIWA MOTOHIRO , MORIMOTO HIDEO
Published: August 2006

Continuous fermentation of grape juice was carried out in a packed bed column system using Lactobacillus casei adsorbed onto ceramic beads. Chemical components in the reaction vessel of this system were compared with those of a free‐cell fermentation. No major differences were noted in the principal components. Diacetyl and methionine levels decreased, however, whereas aspartic acid and cysteine increased. Silica levels increased immediately after initiation of the immobilized cell culture due to elution from the ceramic carrier beads. In two of the five trials the reactor was contaminated with Bacillus megaterium.
Hydration Studies of Maltodextrins by Proton, Deuterium and Oxygen‐17 Nuclear Magnetic Resonance
Authors: MORA‐GUTIERREZ ADELA , BAIANU ION C.
Published: August 2006

Comparative studies of the hydration of maltodextrins were undertaken by proton, deuterium and oxygen‐17 NMR. The 1H and 2H‐NMR transverse relaxation rates of hydrated maltodextrins were sensitive to both chemical exchange with the solvent and hydrogen bonding involving hydroxyl groups. The short average correlation time of water “bound” to maltodextrins (∼ 47 ps) derived from our 17O‐NMR data shows that water is highly mobile and that maltodextrins–at high moisture contents–contribute little to the stability of food products. The onset of aggregation is monitored by all three nuclei. The mechanism of this aggregation process involves hydrogen bonding in un‐heated polysaccharide mixtures and waxy maize starch samples, and is markedly affected by heating to 60°C.
Effect of Temperature on Properties of Extrudates from High Starch Fractions of Navy, Pinto and Garbanzo Beans
Authors: GUJSKA ELZBIETA , KHAN KHALIL
Published: August 2006

High starch fraction (HSF) isolated from three legumes were extruded at different temperatures. Extruded products were evaluated for expansion, density, color and some functional properties. The highest value of expansion was noted for pinto bean, and the lowest for garbanzo, extruded at 132°C. Extrudates from HSF expanded significantly (P < 0.05) less than corn extrudates. Oil absorption capacity increased slightly with increasing temperature and values were lower for navy and garbanzo beans than for pinto HSF and corn. Oil emul‐sification capacity of‐ bean samples was about two times higher compared to corn. Water absorption index (WAI) of pinto and navy beans significantly increased (P < 0.05) from 110°C to 132°C.
Estimating Heat Transfer Coefficients in Liquid/Particulate Canned Foods using Only Liquid Temperature Data
Authors: STOFOROS NIKOLAOS G. , MERSON RICHARD L.
Published: August 2006

A mathematical procedure was developed to estimate heat transfer coefficients for heated rotating cans of food comprised of a liquid and spherical particles. The method uses experimental data for only the fluid temperature, and heat transfer coefficients are obtained by comparing predicted with experimental fluid temperature data in the Laplace transform plane. Results obtained using the procedure were compared with experimentally obtained heat transfer coefficients from the literature for three cases: potato spheres in deionized water, Teflon spheres in deionized water, and aluminum spheres in silicone fluid. Agreement between predicted and experimental results depended upon the agreement of the experimental conditions and the assumptions associated with the model.
Kinetic Parameters for Inactivation of Bacillus stearothermophilus at High Temperatures
Authors: DAVID JAIRUS R.D. , MERSON R.L.
Published: August 2006

High temperature thermal death parameters for Bacillus stearothermophilus TH24 (NCDO 1096) spores in water were determined using a computer‐controlled reactor. The equipment produced and recorded accurate, reproducible square‐wave temperature transients during very short heating times (−0.1 sec). Survivor curves and the phantom thermal death time (TDT) curve between 130°C and 155°C from reactor data were compared to results from oilbath‐heated capillary tubes between 115°C and 135°C. The TDT curve was nonlinear in the high temperature range but could be described by two lines with z = 9.3C° for temperatures between 115°C and 145°C and z = 16.9C° for temperatures above 145°C. An Arrhenius plot did not represent the data better.
Kinetic Model of Lipid Oxidation in Foods
Authors: ÖZILGEN S. , ÖZILGEN M.
Published: August 2006

A general mathematical model in the same form with the logistic equation simulated lipid oxidation in food systems. Almost perfect agreement was found between the model and seventeen sets of data from the literature, obtained with egg yolk, restructured beef and pork nuggets, cooked pork meat, iced gutted dogfish, frozen mackerel fillets and ground raw poultry meat. A simple method was described for the evaluation of the numerical values of the model parameters. Variations of these numerical values were also associated with varying pretreatment and storage conditions.
Kinetics of Methylmethionine Sulfonium Salt Destruction in a Model Particulate System
Authors: BERRY MARTIN F. , SINGH RAKESH K. , NELSON PHILIP E.
Published: August 2006

The kinetics of methylmethionine sulfonium salt (MMS) degradation in a model food system during simulated aseptic thermal processing was investigated under controlled conditions for 1.27 cm side and 2.54 cm side sodium alginate cubes. To determine if concentration of MMS affected the kinetics as influenced by the cube geometry or composition, three concentration levels of MMS were investigated. The initial concentration of MMS in the particles, the particle size and particle shrinkage did not affect the reaction kinetics. The first order reaction rate constant for MMS destruction at 126.7°C was 0.15 min−1 and the activation energy was 28.95 kcal/mole.
Survival of Lactic Acid Bacteria and Their Lactases under Acidic Conditions
Authors: SHAH N. , JELEN P.
Published: August 2006

Effects of sonication, survival, and β‐galactosidase activity of four lactic cultures were investigated in pH 1.5‐3.5 range. Lactobacillus delbruekii subsp. bulgaricus and Streptococcus thermophilus exhibited the highest β‐galactosidase activity in skim milk and broth systems, respectively. The β‐galactosidases from L. delbruekii subsp. bulgaricus, S. thermophilus, and L. acidophilus showed optimum activity in the neutral pH range and 55°C. Viable count of all four cultures decreased most rapidly at pH 1.5, but L. acidophilus and L. delbruekii subsp. bulgaricus survived better than the other organisms. The decrease of enzyme activity of unsonicated cultures with pH was slight, especially at pH 3.5. However, acidification of sonicated cultures to pH 3.5 or lower resulted in rapid and permanent loss of enzyme activity.