bluuebunny/crossref_metadata_2025 huggingface dataset:
Stability of Purified Melon Seed Oil Obtained by Solvent Extraction
Authors: OGUNSUA A.O. , BADIFU G.I.O.
Published: August 2006

The stability of crude or purified melon oil extracted from unroastcd and roasted seeds of Citrullus vulgaris Schrad under selected storage conditions was investigated. Purification did not affect the fatty acid composition of the oil. There were no differences in the levels of alpha‐tocopherol and beta‐carotene in the crude oil from roasted and unroasted seeds. Purification and bleaching of the oil led to losses in both alpha‐tocopherol and beta‐carotene. Purification lowered the stability of the oil even in the presence of added butylated hydroxyanisole. The stability was lowest in the purified and bleached oil.
Flavor Evaluation and Volatile Flavor Constituents of Stored Aseptically Packaged Orange Juice
Authors: MOSHONAS MANUEL G. , SHAW PHILIP E.
Published: August 2006

Samples of commercial orange juice packaged aseptically and stored at 21°C and 26°C were evaluated weekly by a sensory panel using hedonic ratings. Flavor scores were significantly lower than control juice and unacceptable after 1 wk at 26°C and 2 wk at 21°C. The flavor score decreased to 50–60% of the starting value during 6 wk storage. The volatile components, α‐terpineol and ethyl acetate, increased during storage. A component not identified earlier as a volatile citrus component was identified as 2‐(2‐butoxyethoxy)ethanol. This and the observed increase in ethyl acetate during storage might have come from the laminated multilayered package liner. Limonene in juice decreased about 40% during storage. Other major volatile components did not change markedly.
Softening of Canned Apricots: A Chelation Hypothesis
Authors: FRENCH DAVID A. , KADER ADEL A. , LABAVITCH JOHN M.
Published: August 2006

Infiltration of apricot (Prunus armeniaca L.), Patterson cultivar fruits, which are susceptible to rapid softening, with calcium chloride before processing resulted in definite firming of the canned apricots. Non‐susceptible fruits treated with citrate buffers (pH 3.7) showed dramatic post‐process softening. In individual, untreated, early, green fruit, firmness after processing was directly correlated with the bound calcium:citrate ratio. Based on a chelation hypothesis, it was proposed that softening was accelerated when chelators such as organic acid anions removed structural calcium from the cell wall once cell membranes were lysed by heating.
Directly‐Acidified Carrot Slices for Ingredients in Refrigerated Vegetable Salads
Authors: JULIOT K.N. , LINDSAY R.C. , RIDLEY S.C.
Published: August 2006

Several food grade acidulants were evaluated for direct‐acidification of blanched carrot slices for use in salads. Fumaric acid, acetic acid, and a citric/acetic acid combination applied by a non‐buffered immersion‐equilibrium system provided excellent microbial control and satisfactory flavor quality for carrots in salads. Acidified blanched carrots prepared with buffered, potassium sorbate supplemented, fumaric acid solutions ranging in pH from 3.5–4.2 also provided acceptable salads. Dry application of a fumaric/citric acid combination containing potassium sorbate resulted in good retention of fresh‐like properties when carrot slices were stored in carbon dioxide atmospheres. Storing acidified carrots in air caused rapid formation of ionone‐like floral aromas from the autoxidation of beta‐carotene.
Changes in Texture of Green Peas during Freezing and Frozen Storage
Authors: HUNG Y.‐C. , THOMPSON D. R.
Published: August 2006

The effects of freezing (still‐air, air‐blast, and Freon immersion freezing) and frozen storage (−5°, −10° and −15°C for 0 to 48 wk) on texture of cooked frozen peas were examined. Peas frozen by a Freon‐12 immersion method with no appreciable damage to cell structure had firmer and more chewy sensory textural quality compared to those peas frozen by a slower freezing method. Sensory tenderness decreased initially and then increased with storage time to the maximum storage times of 6 wk in −5°C storage, 16 wk in −10°C storage, and 48 wk in −15°C storage. Sensory chewiness increased initially, then remained constant with storage time except in −15°C storage. Generally, the lower storage temperature resulted in less sensory chewiness. The correlation coefficients (r) between sensory and objective measurements for tenderness and chewiness were 0.76 and 0.88 (P < 0.05), respectively.
Chemical and Nutritional Characterization of Lupine Tempeh
Authors: AGOSIN EDUARDO , DIAZ DANIEL , ARAVENA RICARDO , YAÑEZ ENRIQUE
Published: August 2006

Chemical composition and protein value of a tempeh‐related food using lupine as substrate was determined. Bitter lupine grits were slowly degraded as compared to sweet lupine, pointing out the inhibitory action of lupine alkaloids. Any fungal degradation of the latter could be determined. Sweet lupine tempeh was further characterized. Water‐soluble substances increased during the first 17 hr and then only slight changes occurred. The lipid fraction was preferentially metabolized by the fungus, reaching almost 50% loss after 45 hr fermentation. Linolenic and erucic acids were particularly degraded. No significant increase of the NPR values or protein digestibility of fermented lupine were observed. Preliminary results of sensory evaluation of deep‐fat fried lupine tempeh were promising.
Structure‐Digestibility Relationship of Legume 7S Proteins
Authors: DESHPANDE S. S. , DAMODARAN SRINIVASAN
Published: August 2006

Structure‐digestibility relationship was investigated in in vitro model systems for phaseolin and vicilin, the major 7S storage proteins of dry bean and green peas, respectively. Native phaseolin was more resistant to trypsinolysis than vicilin, while heating caused a reversal of proteolysis rates. Conformational studies using far‐uv and near‐uv CD spcctroscopy suggested the native conformatin of vicilin to be far more flexible to thermal treatment and SDS‐induced environmental changes; however, neither the thermal treatment nor the anionic detergent caused a complete randomization of structure in either proteins studied. Ironically, the flexible native conformation of vicilin seemed to induce greater undesirable changes upon heating so as to confer resistance to proteolysis. The possible role of secondary and quarternary structures of these two proteins is descussed in relation to their digestibility.
Reduction of Glucose Content in Potatoes with Glucose Oxidase
Authors: LOW N. , JIANG Z. , OORAIKUL B. , DOKHANI S. , PALCIC M. M.
Published: August 2006

Two commercial glucose oxidase preparations, DeeO 1500 and Fermcozyme CBB‐750, were investigated for their activities and use in decreasing glucose levels in Norland and Shepody potatoes. When DeeO was added at 0.01% by weight of peeled potatoes, glucose of potato extracts of both cultivars was decreased by about 22% when the extracts were first blanched, and about 15% if not blanched, indicating the presence of some inhibitors in raw potatoes. When applied to steam‐blanched potato strips, 0.10% (v/v) solution of Fermcozymc reduced glucose by 25–35%. These experiments showed a potential use of glucose oxidase as a processing aid to reduce nonenzymatic browning in potato products.
Tyrosinase Activity and Isoenzymes in Developing Mushrooms
Authors: INGEBRIGTSEN JANIS , KANG BYOUNG , FLURKEY WILLIAM H.
Published: August 2006

Tyrosinase activities and isoenzymes were monitored in developing mushrooms from small pins to the mature stage. Catechol oxidase activity varied but dihydroxy‐o‐phenylalanine (dopa) oxidase and tyrosinase activities decreased during development. Latent dopa oxidase activity, detected by including sodium dodecyl sulfate in the assay, increased with development of the mushrooms. The electrophoretic profile of dopa oxidase isoenzymes indicated that three forms were present in each developmental stage and that the amount of these three forms decreased with maturation of the fruiting body. The use of phenolic adsorbents to prevent discoloration of crude extracts resulted in decreased enzyme activities and the loss of specific isoenzyme forms.
Effect of Heat Processing of Dried Egg White on In Vitro Iron Bioavailability
Authors: LEAHEY J. M. , THOMPSON D. B.
Published: August 2006

Egg white (EW) was desugared, adjusted to either pH 7 or pH 9, and freeze‐dried. Portions were held at 25°, 50°, 60°, 70° or 80°C for 1 wk. In vitro iron bioavailability (IVIB) was estimated by the method of Kane and Miller (1984) and no differences in IVIB were observed due to EW pH. IVIB of EW held at 50°, 60°, or 70°C was not different (P>0.05) than that of EW held at 25°C [9.87% dialyzable iron (DI)]; only the 80°C treatment led to IVIB lower (6.76% DI, P<0.05) than the 25°C control. Differential scanning calorimetry and nondissociating electrophoresis showed that native protein structure, including that of the iron‐binding protein ovotransferrin, was maintained after the 70°C treatment but not after the 80°C treatment.
Effects of Inositol Tri‐, Tetra‐, Penta‐, and Hexaphosphates on In Vitro Estimation of Iron Availability
Authors: SANDBERG A.‐S. , CARLSSON N.‐G. , SVANBERG U.
Published: August 2006

The effects of inositol tri‐, tetra‐, penta‐, and hexaphosphates on iron solubility were studied in vitro. Pure inositol phosphates (0.125–10 μmol) were added to 1g of freeze‐dried wheat roll and digestion was performed simulating physiological conditions. Soluble iron was used as an index of iron bioavailability. The pure inositol phosphate fractions were prepared by hydrolysis of sodium phytate and separation on anion exchange resin. The inositol phosphates were identified and quantified by HPLC. Addition of 10 μmol inositol hexa‐ and pentaphpsphate reduced iron solubility from 39% (reference) to 0.2% and 6%, respectively, while the same amount of inositol tetra‐ and tri‐phosphate slightly increased the iron solubility. Thus, degradation of inositol hexa‐ and pentaphosphates seemed to significantly reduce the inhibiting effect on iron availability.
An Improvement of the Cell Diffusion Method for the Rapid Determination of Diffusion Constants in Gels or Foods
Authors: DJELVEH G. , GROS J. B. , BORIES B.
Published: August 2006

A diffusion cell was designed to study the apparent diffusion coefficient of solutes through foodstuffs. The mathematical model corresponding to the experimental setup did not assume quasi‐steady state diffusion within the slice of food. It was used to obtain the effective diffusion coefficient of NaCl through 3% Agar gels. The results were compared to those obtained by using two agar gel cylinders at different concentrations. The diffusion coefficient of Cl− in gel at 25°C was obtained with at least the same precision (D = 1.30 × 10−9 m2/sec, SD= 0.03 × 10−9 m2/sec) within less than 110 min compared to a few hours with the two cylinder technique. With the mathematical model used to determine diffusion coefficients, the equilibrium ratio between solute concentration in solution and at the interface of foodstuff can be determined.
A Comparison of Creep Phenomena in Food Protein Gels
Authors: KAMATA Y. , KINSELLA J.E.
Published: August 2006

Rheological properties of gels made by heating (90°C for 20 min) and subsequent cooling (5°C) dispersions of gelatin, soy protein isolate, and a mixture of whey protein and casein were determined by creep measurements at various temperatures. The elastic component of soy protein isolate gels became soft with increasing temperature but did not fully melt even at 90°C. Whey protein concentrate gels deformed continuously upon compression above 70°C, reflecting viscous flow. The gel obtained from a mixture of casein and whey protein concentrate following acidification with glucono‐δ‐lactone and heating revealed significant plastic deformation, indicating the network was formed by packing of small size particles.
Production of Peanut Flour from Microwave Vacuum‐Dried Peanuts
Authors: POMINSKI J. , VINNETT CAROLYN H.
Published: August 2006

Defatted peanut flours with significantly reduced raw peanut taste and nitrogen solubility of 85+% were produced from field Runner peanuts that had been microwave‐vacuum‐dried to maximum temperatures of 80°C and 96°C. The flours were prepared from 4.54 kg of peanuts, dried from 25.5% to less than 10% moisture, at 375 Torr absolute pressure and at 1400 and 813 watts microwave power (2450 MHZ). Peanut temperature at end of drying significantly affected the intensity of the raw peanut flavor. Storage at 23.9°C for 14 months had no significant effects on intensity of the raw peanut flavor. Hexane extraction of blanched peanut kernels showed that mass velocity percolation rates increased with increase in final drying temperature of peanuts.
Processing Yields and Proximate Composition of Cultured White Sturgeon (Acipenser transmontanus)
Authors: PRICE R. J. , HUNG S. S. O. , CONTE F. S. , STRANGE E. M.
Published: August 2006

Cultured white sturgeon, 10–43 months old, were processed into dressed fish, fillets, and steaks. Edible portions from four age classes were analyzed for proximate composition. Round weight yields were: eviscerated, 85–96%; dressed, 53–65%; steaked, 61–74%; skin‐on fillets, 54–61%; and skinless fillets, 32–50%. The proximate composition of the sturgeon averaged 77.3% moisture, 18.2% protein, 3.4% lipid, and 1.2% ash. Protein levels in 10–13‐month‐old fish were significantly lower than in 32–34‐ and 43‐month‐old sturgeon. Lipid levels in 10–13‐month‐old fish, and ash levels in 32–34‐month‐old sturgeon, were significantly higher than in other age classes.
Ascorbic Acid and Protein Content of Potatoes in Relation to Tuber Anatomy
Authors: MUNSHI CYRUS B. , MONDY NELL I.
Published: August 2006

Localization of the nutrients ascorbic acid and protein in the tuber was investigated. Katahdin, Norking Russet, and Shepody potato cultivars were used in this study. Cortex and pith areas were compared for ascorbic acid and protein content. Ascorbic acid of all the three cultivars was significantly higher (p<0.01) in the pith than in the outer cortex region and the protein content was significantly higher (p<0.01) in the cortex than the pith area. The pith region was significantly (p<0.05) higher in nonprotein nitrogen than the cortex area. Since only 2% of the protein content of the entire tuber was located in the peel, peeling the tuber did not cause a significant loss of protein.
On Surface Characterization of Materials Targeted for Food Contact
Authors: McGUIRE JOSEPH , KIRTLEY SIDNEY A.
Published: August 2006

A measurable parameter related to solid surface energy has recently been suggested to provide an index of contact material interactability with components of fluid food. Employing contact angle methods, two series of aqueous solutions were used to evaluate this parameter for a variety of food contact surfaces. Results were independent of which series of diagnostic liquid was used. This supports the identity of the parameter as a true surface property, unique for a given material, and related to the polar character of its surface. Direction is provided toward a means for contact surface characterization which may aid the development and use of models describing food particle behavior at interfaces.
Effect of Ultrasonic Vibration on Fluid‐to‐Particle Convective Heat Transfer Coefficients
Authors: Sastry S. K. , Shen G. Q. , Blaisdell J. L.
Published: August 2006

Studies were conducted to determine the potential of ultrasonic energy as a heat transfer enhancing agent in sterilization applications. Metal transducer particles were immersed in warm liquids with and without sonic agitation, and temperature histories were recorded. Convective heat transfer coefficients were calculated from the solution to the lumped convective heat transfer equation. Results indicate that fluid‐to‐particle heat transfer was significantly enhanced by the use of sonic energy, and that within the range of variables investigated, the amount of enhancement was dependent more on natural convection and standing wave patterns than particle size and energy input per unit mass.
Protein Quality of Selected Muscle Foods as Affected by the Exchange of Dietary Wheat Bran for Cellulose
Authors: MIGUEL R.I. SAN , KUNKEL M.E. , BRIDGES W.C. , DICK R.L. , ACTON J.C.
Published: August 2006

The exchange of 8.4% neutral detergent fiber (NDF) of wheat bran for 8.3% NDF of cellulose in diets containing either beef, chicken, fish or casein as protein sources did not (P>0.05) alter feed consumption, weight gain or energy intake in the protein efficiency ratio (PER) bioassay with weanling rats. Higher (P<0.05) fecal nitrogen (N) excretions and lower (P<0.05) N digestibilities occurred for each protein source when wheat bran was exchanged for cellulose. The exchange also had no effect (P>0.05) on PER or net protein ratio (NPR) of casein or fish protein or on NPR of chicken protein. However, PER and NPR of beef and PER for chicken were reduced (P<0.05) when the dietary fiber was exchanged.
Reducing Microbial Populations on Beef Tissues: Concentration and Temperature of an Acid Mixture
Authors: ANDERSON M. E. , MARSHALL R. T.
Published: August 2006

A mixture of 2% acetic, 1% lactic, 0.25% citric and 0.1% ascorbic acid was applied to beef core samples of muscle inoculated with bacteria. Experimental variables were concentration and temperature of mixed acids and type of microorganism. Overall, an increase in either mixed acids concentration (0 to 3%) or temperature (20 to 70°C) resulted in reductions in counts of about one logi0 for aerobic bacteria and S. ryphimurium, less than one log10 for Enterobacteriaceae, and about one‐half log10 for E. coli. Initial meat surface pH dropped to 4.3 after treatment with 3% mixed acids solution but rose to 5.2 after 24 hr. Overall, this mixture of acids performed about the same as acetic acid or lactic acid under the same conditions.
Effects of Algin/Calcium and Adipic Acid Concentration on Muscle‐Juncture Formation
Authors: JOHNSON R.C. , MULLER T.S. , ROMANS J.R. , COSTELLO W.J. , JONES K.W.
Published: August 2006

Efficacy of a binding gel, containing various concentrations of algin/ calcium (ALG/Ca) and adipic acid (AD), between large meat pieces in both raw, refrigerated and cooked forms was examined. Functionality of the binding gel was based upon the ability to uniformly apply the gel solution and the binding capabilities of the gel. Optimum ALG/ Ca concentration for easy application and production of maximum juncture success and binding strength in both the raw and cooked states was determined. Juncture success and binding strength in both states were maximized and surface discoloration minimized with the theoretically ideal AD to Ca ion ratio (0.5:1.0). These results indicated that large muscle pieces might be adhesively bound by ALG/Ca/AD gels to produce structured products.
Gelation of Bovine Serum Albumin by Glutathione
Authors: HIROSE MASAAKI , NISHIZAWA YURIKO , LEE JIN YOUNG
Published: August 2006

Bovine serum albumin (BSA) formed an opaque gel when incubated at 37°C with reduced glutathione (GSH). Gelation was highly dependent on concentration of GSH and pH, at 70 mM GSH and pH 8.2 BSA showed maximum gel hardness. Sodium dodecyl sulfate polyacrylamide gel electrophoresis and the number of protein sulfhydryls revealed that gelation involves reduction of intramolecular disulfides in BSA and subsequent cross‐links through intermolecular protein disulfides. Gelation was strongly inhibited by high concentrations of salts; inhibitory effects were highly dependent on species of anions, but not cations.
Development of a Test to Predict Gelation Properties of Raw Turkey Muscle Proteins
Authors: FOEGEDING E. ALLEN
Published: August 2006

A method for extraction and fractionation of muscle proteins into five fractions based on salt (NaCl) solubility was developed. The influence of protein extractability, solubility, muscle pH and total protein on gelation was investigated. Shear stress (gel strength) and shear strain (gel deformability) at failure of cooked (70°C) comminuted turkey breast gels were correlated with the 10 min protein extract and proteins soluble in 0.30–0.35M NaCl. Shear strain was correlated with muscle pH and shear stress was sensitive to total protein. Meat pH and the extraction/fraction method can be used on raw meat to indicate functional properties related to texture of cooked meat.
Restructuring of Mechanically Deboned Chicken and Nonmeat Binders in a Twin‐screw Extruder
Authors: ALVAREZ V.B. , SMITH D.M. , MORGAN R.G. , BOOREN A.M.
Published: August 2006

A twin‐screw cooking extruder was used to restructure mechanically deboned chicken (MDC) in combination with three nonmeat binders, corn starch (CS), soy protein isolate (SPI) and wheat gluten (WG), at concentrations of 10–30%. Extrudates were evaluated by apparent tensile stress (ATS), Warner Bratzler shear stress (WBSS), proximate composition and reheat yield. SPI and WG were less effective than starch for increasing the ATS and WBSS of extruded MDC. The effects of die temperatures between 71–115°C on chemical and textural properties of extrudates containing 10% and 15% starch were investigated. The ATS and WBSS increased as a function of temperature up to 104°C. Fat content and lipid oxidation decreased as extrusion temperatures increased.
Factors Influencing Catalysis of Lipid Oxidation by the Soluble Fraction of Mackerel Muscle
Authors: DECKER ERIC A. , HULTIN HERBERT O.
Published: August 2006

Analysis of a soluble fraction (press juice) from mackerel muscle indicated 8% of the iron and 7 to 38% of the copper was associated with fractions with molecular weights of < 10 kilodaltons (KD). Storage of mackerel muscle resulted in an increase in < 10 KD iron but not copper. Storing frozen‐thawed muscle resulted in increases in both the < 10 KD iron and copper. Storing mackerel resulted in decreased ascorbate and increased hemin in the press juice. Separation of the press juice into <5 KD and >5 KD fractions indicated both low and high molecular weight components are required for maximal lipid oxidation in mackerel muscle.
Nutrients and Chemical Residues in One‐ to Two‐Pound Mississippi Farm‐raised Channel Catfish (Ictalurus punctatus)
Authors: NETTLETON JOYCE A. , ALLEN WILLIAM H. , KLATT LORI V. , RATNAYAKE W.M.N. , ACKMAN ROBERT G.
Published: August 2006

Composite samples of Mississippi farm‐raised channel catfish (FRCC) fillets were analyzed at four different seasons for the following: proximate composition, cholesterol, fatty acids, eight vitamins, eleven minerals, four heavy metals and eight chemical residues. Nutrients and other compounds did not vary appreciably with season. Mississippi FRCC were higher in fat, calories and thiamin compared with USDA and wild catfish data and had much less cholesterol than previously reported. Monounsaturates comprised over half the fatty acids in FRCC and omega‐3 fatty acid content was low. Chemical residues were not detectable or present in extremely small amounts.
Relationships Between Physicochemical Properties of Nonfish Protein and Textural Properties of Protein‐incorporated Surimi Gel
Authors: CHUNG K. H. , LEE C. M.
Published: August 2006

The physicochemical properties of nonfish proteins were correlated with textural properties of nonfish protein gels and nonfish protein‐incorporated surimi gels. Both cold and thermal hydration ability (by centrifugation) of nonfish proteins strongly correlated with compressive force (cohesiveness) of nonfish protein‐incorporated surimi gel (r = 0.94 for cold; r = 0.95 for thermal). Hydrophobic amino acid groups in nonfish protein inversely correlated with compressive force (r =−0.88) and penetration force (r =−0.78) of nonfish protein‐incorporated surimi gel. Thermal behavior of nonfish protein affected the gel characteristics of nonfish protein and surimi with nonfish protein‐incorporated.
Strength of Gels Prepared from Washed and Unwashed Minces of Hoki (Macruronus novaezelandiae) Stored in Ice
Authors: MACDONALD G. A. , LELIEVRE J. , WILSON N. D. C.
Published: August 2006

Washed and unwashed fish minces were prepared from hoki that had been stored in ice. Gels were formed from the minces, cooked at both 60°C and 90°C and assessed by puncture, torsion and a folding test method. The strength of the gels decreased as the fish were stored. However, after 10 days, the strength of gels made from hoki minces still compared favorably with gels made from other commercial fish species without storage. This suggests that manufacture of hoki surimi on‐shore may be practical. Fish freshness as evaluated by sensory methods was closely related to the K value and gel strength. Hence K values might provide the basis of a raw material quality control system for an on‐shore surimi plant.
Simulation of the Vacuum Infusion Process using Idealized Components: Effects of Pore Size and Suspension Concentration
Authors: BARRETT ANN H. , ROSS EDWARD W. , TAUB IRWIN A.
Published: August 2006

Vacuum infusion of porous food matrices (i.e., extruded starch crackers) with calorically dense suspensions of food powders in fat was investigated in an ideal system. Experiments involved infusion of model matrices with lipid suspensions consisting of milled, size‐characterized sucrose in corn oil. The influences of pore size/particle size ratio and suspension concentration on the penetration of liquid and particles were determined. A mathematical model that allows prediction of future behavior was fitted to the test results. The model indicates that dry‐weight particle penetration is strongly correlated with pore size and independent of initial particle concentration. Infusion of liquid plus particles was increased by raising porosity and lowering particle concentration.
Heating Milk: A Study on Mutagenicity
Authors: BERG H.E. , VAN BOEKEL M.A.J.S. , JONGEN W.M.F.
Published: August 2006

The mutagenicity of heated milk and model systems was investigated by the Ames mutagenicity assay. Heating varied from pasteurization to in‐bottle sterilization to ultra‐high‐temperature (UHT) heat‐treatment. No mutagenic response was found in heated milk or model systems. Early Maillard reaction products formed in heated milk or milk‐resembling model systems apparently did not show mutagenic activity in the Ames‐test. Milk that was burnt to the pan was also investigated. Chloroform and ethanol extracts of this milk showed mutagenic activity. Evidence showed this was due to Maillard reaction products. The antimutagenic activity of casein, reported in earlier studies, was confirmed.
Viability of Lactobacillus plantarum in Orange Juice under Low pH and Temperature Conditions
Authors: PARISH M.E. , SADLER G.D. , WICKER L.
Published: August 2006

A strain of Lactobacillus plantarum, isolated from fermenting orange juice (OJ), was inoculated into unpasteurized or reconstituted OJ and held under low pH/low temperature conditions. Viability decreased more rapidly at subfreezing temperatures near – 5°C than at lower or higher temperatures. Viability decreased 0.37 log CFU/mL/hr at ‐ 6.6°C and 0.05 log CFU/mL/hr at ‐ 18°C. Rates of population decrease in frozen samples at ‐ 5°C were about three times greater than in unfrozen samples at the same temperature. An inverse linear relationship existed between rate of population decrease (log CFU/mL/day) at ‐ 7°C and OJ pH, with the rate of decrease at pH 4.1, about 1 log cycle lower than at pH 3.5 (0.024 and 0.60, respectively).
Antimutagenic Effects of Apple Juices: Interference with Heat Load Measurement by Microbiological Methods
Authors: EKASARI INDRIATI , JONGEN W.M.F. , PILNIK W.
Published: August 2006

Whole heated clear apple juice subjected to a modified Salmonella mutagenicity assay did not show any mutagenic response. However, when fractionated, one fraction obtained from gel filtration did show a dose‐related mutagenic response. This suggested the presence of antimutagenic factors. The Ames standard mutagenicity test was used to investigate the antimutagenic activity of apple juice samples against the direct acting mutagens nitroquinoline‐N‐oxide (NQO) and N‐methyl‐N′‐nitro‐N‐nitrosoguanidine (MNNG). There was a dose and heat load dependent reduction in the mutagenicity of both mutagens, indicating the presence of antimutagenic factors.
Chemical and Physical Changes in Beet (Beta vulgaris L.) Root Tissue During Simulated Processing–Relevance to the “Black Ring” Defect in Canned Beets
Authors: PARKIN KIRK L. , IM JI‐SOON
Published: August 2006

Preheating slices of beet root tissue at 40 to 60°C led to a loss in tissue integrity indicated by higher leakage of electrolytes and endogenous pigments, and increases in water soluble pectin content. When tissue slices were incubated at 25°C for 1 hr after preheating at 50 to 60°C, reducing sugar increased. Incubation after preheating at 40 to 60°C resulted in decreased phenolic acid content. Endogenous poly‐phenoloxidase and peroxidase retained about 50% of their original activity after preheating for 5 min at 70 and 60°C, respectively. These results bear relevance on the occurrence of the “black ring” defect in canned beets.
Application of Browning Inhibitors to Cut Apple and Potato by Vacuum and Pressure Infiltration
Authors: SAPERS G.M. , GARZARELLA L. , PILIZOTA V.
Published: August 2006

Vacuum and pressure infiltration were investigated as means of applying ascorbatc‐ or erythorbate‐based enzymatic browning inhibitors to apple and potato cut surfaces. Apple plugs infiltrated at 34 kPa pressure showed more uniform uptake of treatment solution and less extensive water‐logging than plugs vacuum‐infiltrated at 169–980 mB. Delicious and Winesap plugs and dice gained 3–7 days of storage life at 4°C when treated by pressure infiltration, compared to dipping. However, infiltrated dice required dewatering by centrifugation or partial dehydration to prevent water‐logging. Pressure infiltration at 108 kPa extended the life of potato plugs by 2–4 days, compared to dipping, but was ineffective with potato dice.
Low Temperature Sweetening in Susceptible and Resistant Potatoes: Starch Structure and Composition
Authors: BARICHELLO VALERIE , YADA RICKEY Y. , COFFIN ROBERT H. , STANLEY DAVID W.
Published: August 2006

Starch isolated from ND 860–2 potatoes, which were resistant to chillsweetening, had higher amylose and lower amylopectin as well as a higher crystallinity as compared to starch isolated from Norchip potatoes, which were susceptible to low temperature sweetening. ND 860–2 starch exhibited greater resistance to α‐amylase attack and amorphous swelling as well as higher gelatinization temperatures and onset swelling temperatures than starch isolated from Norchip. Examination of starch granule structure using bright field light microscopy indicated crystalline concentric rings in ND 860–2 not seen in Norchip. Scanning electron microscopy of granules incubated with a‐amylase indicated more intact ND 860–2 starch granules compared to Norchip. These data strongly suggest that starch granule composition is a factor differentiating the low‐temperature sweetening sensitive cultivar from the resistant potato seedling.
Calcium Oxalate Crystals: The Irritant Factor in Kiwifruit
Authors: PERERA CONRAD O. , HALLETT IAN C. , NGUYEN TUAN T. , CHARLES JUDITH C.
Published: August 2006

The cause of irritation in the mouth, when kiwifruit nectars and dried kiwifruit products are ingested, was investigated. Idioblast cells that contain raphide crystals of calcium oxalate were isolated from inner pericarp tissue of the fruit and studied by light and electron microscopy. An experienced panel of 9 judges detected an irritation from sweetened apple puree when isolated raphide crystals were incorporated at the rate of 30 mg oxalate/100g of puree. Sensory and microscopic studies showed evidence that the irritation was caused by sharp calcium oxalate crystals exposed during processing.
Spray Drying of Roselle (Hibiscus sabdariffa L.) Extract
Authors: AL‐KAHTANI HASSAN A. , HASSAN BAKRI H.
Published: August 2006

Hibiscus sabdariffa (Roselle) powder was produced by pilot scale spray drying using single strength and vacuum concentrated water extract of its calyces. Powders were analyzed for moisture, protein, vitamin C, total soluble solids (TSS), pH, particle size, bulk density, solubility, dispersibility, hygroscopicity, and microbiological status. The lowest inlet air temperature (198.5°C) resulted in the product with best protein content (12.43%), retention of vitamin C (82.76 mg/ 100g), and solubility (dissolving in 97 sec); as well as the highest moisture content (3.78%) in the product. The powder showed a noticeable tendency to stick to internal surfaces of the drying chamber particularly with concentrated solutions at higher temperatures.
Thermal Destruction of Cysteine and Cystine Residues of Soy Protein under Conditions of Gelation
Authors: WANG C.H. , DAMODARAN SRINIVASAN
Published: August 2006

Thermal destruction of cysteine and cystine residues of soy proteins was investigated under gelation conditions. Significant cysteine and cystine were lost as a function of heating time. The rate and extent of loss was affected by heating temperature, pH, salt concentration and viscosity of the protein solution. Greatest effects were from heating temperature, pH and viscosity. A significant amount was lost even at pH 7.0 at 100°C. Amino acid analysis revealed that thermal destruction of cysteine and cystine at high protein concentration and near neutral pH did not result in formation of lysinoalanine. The results can be useful to preserve nutritional quality in thermal processing of soy proteins.
Development of Wash and Cook‐proof Methods for Vitamin Enrichment of Rice Grains
Authors: JOSEPH E.W. , LIUZZO J.A. , RAO R.M.
Published: August 2006

Rice grains were simultaneously enriched with vitamin (niacin, thiamin, riboflavin, and pyridoxine) mixes and cross‐linked under acidic and alkaline conditions using acetaldehyde and epichlorohydrin, respectively. Results indicated that acidic cross‐linked grains absorbed more vitamins than corresponding alkaline cross‐linked rice (P<0.05). The acidic‐linked rice retained the vitamins even after severe washing. Cooking and canning reduced vitamin levels in the unenriched rice below those in the unprocessed (raw) samples (P<0.05); conversely, enriched samples retained significantly (P<0.05) higher levels than the untreated control. Data from the cooking/canning processes suggested that the acidic cross‐linking/enrichment treatments allowed the vitamins to penetrate the surface of the rice grains.
Extraction and High Performance Liquid Chromatographic Enrichment of Polyphenol Oxidase from Theobroma cacao Seeds
Authors: WONG MICHAEL K. , DIMICK PAUL S. , HAMMERSTEDT ROY H.
Published: August 2006

Polyphenol oxidase (PPO) was extracted from cocoa beans and subsequently purified using ammonium sulfate precipitation followed by high performance liquid chromatography (HPLC) for enrichment. HPLC analysis was performed using hydrophobic interaction chromatography which resulted in a 6.5‐fold enrichment and a 24.6% recovery of the enzyme. Enrichment was confirmed using polyacrylamide gel electrophoresis under nondenaturing conditions. Comparison of enzyme‐ and protein‐stained electrophoretic gels revealed the presence of possible multiple molecular forms of PPO and the absence of non‐enzymic contaminating protein, indicating a rapid procedure of enzyme extraction and enrichment.
Pyrylium Betaines as Reactive Intermediates in Maillard Reaction
Authors: YAYLAYAN V.A. , LACHAMBRE S.
Published: August 2006

Evidence that pyrylium betaines (1,3‐dipoles) were one of the precursors of early Maillard polymers was obtained by following the formation of brown polymers at 450 nm in the presence and absence of norbornene (a dipolarophile) in a model system consisting of glucose and glycine; the results indicated that trapping the pyrylium betaines with norbornene by a 1,3‐cycloaddition reaction, supressed the absorption at 450 nm. In addition, other model systems were studied consisting of glucose and each of arabinose, acetaldehyde and glyceraldehyde in the presence of maleic anhydride (also in the presence of norbornene) to distinguish between 1,3‐dipolar cycloaddition reactions and Diels‐Alder type cyclizations. All the results indicated the possibility of pyrylium betaine formation in Maillard model systems.
Effect of Antioxidant and Conditions on Solubility of Irradiated Food Proteins in Aqueous Solutions
Authors: KRUMHAR K.C. , BERRY J.W.
Published: August 2006

Food proteins were examined after irradiation. Effects of exposure, headspace gas, buffer, pH, antioxidant, total protein and type, and storage were tested. Decreases in solubility of native protein and formation of high MW polymers were observed. Destruction was greatest at low protein concentrations, high radiation dose (10 kGy) and pH 7. High protein concentration (5‐10%), glucose, pH 5–6 and propyl gallate were protective. Ascorbic acid effects were concentration dependent. Nitrogen headspace effect was influenced by antioxidant and was smaller than expected. Propyl gallate plus glucose or SDS helped maintain protein solubility and size at high radiation rates. Marked declines in isoelectric pH consistent with lysine destruction were revealed.
Production of Ascorbate Free Radicals in Infant Formulas and Other Media
Authors: CHAMPAGNE E.T. , HINOJOSA O. , CLEMETSON C.A.B.
Published: August 2006

The effects of pH on ascorbate free radical production in ascorbic acid‐supplemented cow's milk, soy‐ and milk‐based infant formulas and in aqueous ascorbic acid solutions were examined. Formula and milk components decreased ascorbate free radical concentrations. Ascorbate free radical levels in pepsin‐hydrolyzed soy and milk formulas were no different from those of unhydrolyzed formulas. At the phytate: iron molar ratio in the formulas, phytate decreased ascorbate free radical levels in pH 2.0 and 7.0 ascorbic acid solutions containing iron by about 35% and 50%, respectively. This antioxidant effect of phytate was not observed in soy‐based and phytate‐spiked milk‐based formulas.
Lack of Vitamin B6 Activity of 6‐Hydroxypyridoxine
Authors: III J.F. GREGORY , LEATHAM K.
Published: August 2006

Hydroxylation of the C‐6 position of pyridoxine has been described recently as a mechanism for the degradation of vitamin B6 in foods. The nutritional properties of the resulting 6‐hydroxypyridoxine in mammals have not been previously evaluated. 6‐Hydroxypyridoxine was synthesized and its structure confirmed by UV and NMR spectroscopy. A rat bioassay with multiple dose levels was conducted to compare the vitamin B6 activity of pyridoxine and 6‐hydroxypyridoxine with respect to a variety of indices of vitamin B6 metabolism. By all criteria employed, 6‐hydroxypyridoxine exhibited neither vitamin B6 nor antivitamin B6 activity and, thus, is nutritionally inert.
Use of a Flow Cell Apparatus to Determine the Emulsifying Properties of Casein
Authors: BRITTEN MICHEL , GIROUX HÉLÈNE J.
Published: August 2006

A newly designed flow cell apparatus was used to investigate the effect of protein concentration and oil fraction on casein stabilized emulsions. Emulsifying capacity showed an exponential decrease with increasing casein concentration. The microstructure of the emulsion suggested that insufficient surface coverage and mechanical stress on oil droplets' membranes were factors responsible for its collapse. Protein load and membrane thickness calculations, showed that the minimal surface coverage, or the minimal membrane thickness required to prevent emulsion collapse, increased with the oil fraction. This last relationship is suggested as a membrane resistance indicator for film forming proteins.
Enzymatic Production of High‐Protein Amaranth Flour and Carbohydrate Rich Fraction
Authors: PAREDES‐LÓPEZ O. , BARBA DE LA ROSA A.P. , CÁRABEZ‐TREJO A.
Published: August 2006

The basic conditions of an enzymatic process to produce high‐protein amaranth flour (HPAF) and carbohydrate rich fraction (CRF) from raw flour were determined. Commercial preparations of α‐amylase and glucoamylase were used. Conditions for both enzymes were: 20% (w/v) slurries of gelatinized whole flour and 0.10% (v/w) enzyme; for amylase, pH 6.5, 70°C and 30 min liquefaction time; for glucoamylase, pH 4.5, 60°C and 60 min. The yield of HPAF was 38–39%. HPAF from both enzymes had 26–28% protein, 10–16% fat and 40–52% starch. Protein digestibility (76%) and reactive lysine (6.6–7.1 g/100g protein) of HPAF were comparable to raw flour. CRF had a 17–21 dextrose equivalent.
Microfiltration and Ultrafiltration Comparison for Apple Juice Clarification
Authors: WU M. L. , ZALL R. R. , TZENG W. C.
Published: August 2006

Unpasteurized raw apple juice processed by microfiltration (MF) or ultrafiltration (UF) was evaluated for quality and the methods compared for process efficiency. Juice permeate was analyzed for total solids, soluble solids, color, turbidity, pH and acidity. Apple juice processed by MF was significantly (p < 0.05) darker, more turbid, contained higher total and soluble solids than juice processed with UF, and was preferred by a taste panel. MF processed more permeate per unit time than UF under similar operating conditions with no noticeable difference in power consumption (watt‐hr/L).
Diacetyl Measurement in Orange Juice Using Differential Pulse Polarography
Authors: SADLER G. , PARISH M. , DAVIS J.
Published: August 2006

Reconstituted single strength orange juice was distilled to recover diacetyl. 0.5 mL of 1N LiOH was added to 4.5 mL of distillate. Using a static mercury drop electrode, a current vs potential scan was performed between −0.7 and −1.10 vs an Ag/AgCl reference electrode. The reduction potential for diacetyl was −0.83 V. Peak heights were proportional to concentration throughout the test range (8.3 ppb to 1 ppm). Diacetyl recoveries were approximately 85%.
Multiple Comparisons for Ranked Data
Authors: BEST D.J.
Published: August 2006

Multiple comparisons for ranked data should be carried out in the same manner as they would be for continuous, normally distributed data rather than by use of published tables. A simple example and computer simulations support this approach.
Effect of Heating and Elevated Temperature Storage on Cheese Whey
Authors: MORR C.V.
Published: August 2006

The effect of heating and storage of sweet (pH 6.1–6.3) and acid (pH 4.75) cheese whey for up to 10 hr at 62.8°C (145°F) on pH, titratable acidity, total bacteria count and protein denaturation was investigated. Heating and elevated temperature storage reduced the total bacteria counts of both types of whey to ≤ 100 mL−1 and stabilized their titratable acidity at 1.60–1.65%. These treatments resulted in up to 13.4% and 6.7% protein denaturation in sweet and acid whey, respectively, as measured by the pH 4.6 solubility method. SE‐ HPLC data confirmed that these elevated temperature treatments resulted in slight losses of major proteins.
Determination of Safrole and Isosafrole in Ham by HPLC with UV Detection
Authors: ZUBILLAGA M.P. , MAERKER G.
Published: August 2006

An improved method has been developed for the determination of safrole and isosafrole in meat. To ham were added known amounts (5–100 ppm) of either compound or mixtures of both. The samples were extracted with hexane/ethyl acetate (95/5, v/v) by a dry column procedure, and the eluate was analyzed by HPLC with UV detection. Recoveries ranged from 91–102% for the individual components and from 93–100% for mixtures. The improved method requires less analysis time and instrumentation and is more sensitive than a previous method.
Temperature Effects on Food Contact Surface Properties
Authors: McGUIRE JOSEPH , SPROULL ROBERT D.
Published: August 2006

Measurable contact surface properties related to surface energy have been suggested to provide direction for prediction and control of fluid food behavior at interfaces. With respect to fouling of heat exchangers, such properties may be useful for development of mathematical models which incorporate surface‐related terms. Surface energy parameters for a variety of contact surfaces were recorded at temperatures from 7 to 80°C. A linear dependence was observed between surface energy properties and temperature. This suggests a need to account for temperature influences on surface energy in further development of models which describe surface interactions undergone by food components at temperatures outside of the ambient range.
Effects of Feeding Elevated Levels of Monounsaturated Fats to Growing‐finishing Swine on Acceptability of Boneless Hams
Authors: SHACKELFORD S. D. , REAGAN J. O. , HAYDON K. D. , MILLER M. F.
Published: August 2006

The processing and sensory characteristics were investigated on boneless, fully‐cooked hams produced from swine fed diets high in mon‐unsaturated fat. First impression and overall tenderness scores were higher for hams from the animal fat, safflower oil and sunflower oil treatments than from the control and canola oil treatments (P < 0.05). No differences were noted across treatments for juiciness, saltiness, flavor intensity or overall palatability; however, off‐flavors were (P < 0.05) most frequently in samples from the canola oil treatment. Hams from swine fed 10% safflower oil or sunflower oil were acceptable in sensory, physical and chemical characteristics.
Effect of Moisture Content on Density, Heat Capacity and Conductivity of Restructured Pork/Soy Hull Mixtures
Authors: MUZILLA M. , UNKLESBAY N. , UNKLESBAY K. , HELSEL Z.
Published: August 2006

Sixteen restructured pork/soy hull mixtures were studied. Incorporation of unprocessed and processed and two particle sizes of hydrated soy hulls in the mixture resulted in moisture contents ranging from 74% to 85%. Standard laboratory procedures were used to measure density, heat capacity and thermal conductivity. Thermal diffusivity was calculated as a mathematical function of these three properties. Thermal diffusivity values were affected the most (1.14–2.01 × 10‐7 m2/sec) by moisture, followed by heat capacity (2.75–4.18 J/g°C), and thermal conductivity (4.80–5.72 x 10‐3W/cm°C). No significant changes in density occurred (1.02–1.06 g/cm3).
Characteristics of Beef Batters as Influenced by Electrical Stimulation and Postmortem Salting Time
Authors: SEMAN D. L. , MOODY W. G.
Published: August 2006

Changes were evaluated in functional and textural properties of beef batters altered by mincing, postmortem salting time and electrical stimulation. Histological examinations showed raw batters from non‐stimulated (NS) meat exhibited uniform fat dispersal throughout the protein matrix regardless of salting time; however, fat channeling, increased fat and gel‐water release, lower hardness and gel strength along with reduced apparent viscosity were observed in electrically stimulated (ES) meat when salting was delayed. Changes in amounts of salt‐soluble protein were not consistent. Effects of pH on water‐holding capacity and myofibrillar swelling accounted for most changes observed in batters from ES muscles. However, increases in apparent viscosity and hardness may have been a consequence of rigor onset.
Influence of Enzymatic Hydrolysis on Structure and Emulsifying Properties of Sardine (Sardina pilchardus) Protein Hydrolysates
Authors: QUAGLIA G.B. , ORBAN E.
Published: August 2006

The influence of enzymatic modification with Alcalase was studied on surface hydrophobicity, molecular weight distribution and emulsifying properties of ten hydrolysates from sardine differing in degree of hydrolysis. Surface hydrophobicity was evaluated fluorometrically using 1 anilino‐8‐naphthalenesulfonate (ANS); molecular weight distribution was determined by gel chromatography on a Superfine Sephadex G50. Emulsifying capacity and stability were evaluated as functions of pH values and product concentration, in comparison with sodium caseinate. Results showed emulsifying properties, surface hydrophobicity and the high molecular weight fraction decreased as degree of hydrolysis increased. Thus production of hydrolysates with desired molecular structures and emulsifying properties is possible.