bluuebunny/crossref_metadata_2025 huggingface dataset:
Starch Gelatinization in Chemically Leavened Bread Baking
Authors: ZANONI B. , SMALDONE D. , SCHIRALDI A.
Published: August 2006

Differential scanning calorimetry was employed to assess the kinetics of the starch gelatinization in bread doughs. The process of gelatinization, which depended on the depth from the surface of the sample, followed the same first order kinetics in the baking treatment and in the calorimetric scan. Its progress was predictable when the local temperature could be suitably recorded. Accordingly, thorough temperature control allowed monitoring starch gelatinization and bread baking.
Monitoring Freeze‐Drying by Low Resolution Pulse NMR: Determination of Sublimation Endpoint
Authors: MARQUES J.P. MONTEIRO , LE LOCH C. , WOLFF E. , RUTLEDGE D.N.
Published: August 2006

An NMR method was developed for detection of the sublimation period endpoint during the freeze‐drying of potato pieces. Longitudinal (T1 and transverse (T2) relaxation times were estimated using rapid NMR methods. Samples were immediately examined to determine presence of a frozen core. The plot of T1 vs T2 showed an abrupt increase at a point corresponding to the complete elimination of the frozen core. Similar Tj vs T2 curves were observed when monitoring freeze‐drying of a single potato piece inside the NMR probe‐head. The detection of an anomalous freeze‐drying is possible by monitoring the T1 the T2 or the free induction decay signal.
Rheology of Sol‐Gel Thermal Transition in Cowpea Flour and Starch Slurry
Authors: OKECHUKWU P.E. , RAO M.A. , NGODDY P.O. , McWATTERS K.H.
Published: August 2006

A thermal scanning rigidity monitor was used to follow rheological changes during heating of cowpea flour and starch slurries. The gelantinization temperature of cowpea starch was in the range 67–78°C. For cowpea flour, in addition to starch gelatinization, a shallow plateau was observed. The starch gelatinization onset temperature shifted from 67°C for starch to 72C for 25% cowpea flour that contained 12–15% starch. The modulus (G′) of cowpea gels increased with flour concentration according to a power relationship. Rigidity of the cowpea starch and flour gels decreased at temperatures higher than 78 and 87°C, respectively.
Lactate Dehydrogenase Activity in Bovine Muscle as a Means of Determining Heating Endpoint
Authors: STALDER J.W. , SMITH G.L. , KEETON J.T. , SMITH S.B.
Published: August 2006

Influence of pH, salt, phosphate, cooking temperature, muscle variation, carcass sex and maturity on lactate dehydrogenase (LDH, E.C. 1.1.1.27) activity in bovine tissue slurries was investigated. LDH activity declined sharply as temperature neared 63°C at pH 5.6 and 6.4, but no activity was detected at pH 4.8. As salt and phosphate concentrations increased, LDH activity decreased. LDH activity varied greatly from muscle to muscle. Carcasses did not differ in LDH activity by sex, but showed a decrease in activity as maturity increased. LDH has potential as a determinant of the minimum heating endpoint in precooked beef and a rapid analytical test could be developed.
Flavor and Oxidative Stability of Ground Beef Patties as Affected by Source and Storage
Authors: McMILLIN K.W. , BIDNER T.D. , FELCHLE S.E. , DUGAS S.M. , KOH K.C.
Published: August 2006

Chuck muscles and fat from silage plus grain‐ and forage‐fed steers were stored 7 days at 4°C before patty manufacture or processed into patties and stored at 4°C or −32°C. The thiobarbituric acid values were constant from 0 to 4 days for frozen patties but decreased (P<0.05) for refrigerated patties. Evaluated by an 11‐member trained sensory panel, frozen patties had lower (P<0.05) rancid flavor intensity than refrigerated patties; rancid flavor increased from 0 to 2 or 4 days storage in refrigerated patties. Frozen patties from silage plus grain‐fed steers had higher (P<0.05) beefy flavor intensity scores than those from forage beef. However, diet source had no effect (P>0.05) on refrigerated patties.
Storage and Bacterial Contamination Effects on Myofibrillar Proteins and Shear Force of Beef
Authors: CROUSE J.D. , KOOHMARAIE M. , DICKSON J.S.
Published: August 2006

Thirty‐two steaks from the longissimus muscle, fifth rib to third lumbar vertebra, were obtained from youthful carcass beef. Half were sterilized by ultraviolet light and all vacuum packaged and stored for 1, 14, 28 or 57 days at 2°C. After storage, steaks were examined for microbial populations, myofibril fragmentation index (MFI), cooking characteristics and shear force (SF). Aerobic and anaerobic counts decreased during storage. Psychrotrophic counts were low throughout. Sterilization had no effect on SF or MFI. Cooking loss tended (P < 0.09) to increase with time of storage. SF values decreased and MFI values increased through day 14, but remained relatively constant after that. Results of SDS‐PAGE, SF and MFI indicate major changes in proteolysis of myofibrils and tenderness were completed by day 14.
Starter Culture and Time/Temperature of Storage Influences on Quality of Fermented Mutton Sausage
Authors: WU W.H. , RULE D.C. , BUSBOOM J.R. , FIELD R.A. , RAY B.
Published: August 2006

Rate of acid production and ability to produce antimicrobial activity were tested on P. acidilactici H and L. plantarum 27 during growth in a sausage formula mixture. Lactacel 75 was used as control. Starter culture did not affect water activity, pH, ash or protein content, fatty acid composition (except for nonadecanoate), cholesterol content or retention of moisture, protein, fat, ash or fatty acids. Sausages made with P. acidilactici H had the lowest (P<0.05) retention (89.6%) of cholesterol during processing and storage. Sensory evaluation of fermented sausage and bologna prepared from the two starter cultures or from Lactacel 75 indicated both products were acceptable after 50–60 days storage at 4°C.
Isolation of Low‐Molecular‐Weight Taste Peptides from Vacherin Mont ?Or Cheese
Authors: MOJARRO‐GUERRA SANDRA H. , AMADÒ RENATO , ARRIGONI EVI , SOLMS JUERG
Published: August 2006

Vacherin cheese samples weie extracted with water and the extracts fractionated by ultrafiltration excluding compounds with a molecular weight less than 1,000. Extract aliquots were fractionated by ligand exchange chromatography on a Sephadex derivative containing N‐(2‐pyridylmethyl)glycine‐groups in Cu2+ form, permitting a specific group separation of peptides. Five peptide sub‐groups were then chromato‐graphed on Aminex A6 and Durrum DC 4 resin. Nine fractions from these separations were characterized by manual gas‐phase isofhiocy‐anate degradation and HPLC of the amino acid derivatives. Seven peptides could be identified: H‐Leu‐Pro‐OH, H‐Val‐Pro‐OH, H‐Phe‐Pro‐OH, H‐Lys‐Pro‐OH, H‐Gly‐Pro‐Val‐Arg‐OH, H‐Tyr‐Pro‐OH, and H‐Arg‐Pro‐OH. A partial elucidation of the structure was possible for peptides containing Asp/Pro/Val/Leu, Glu/Leu, and Ala/Pro.
Preprocessing Ice Storage Effects on Functional Properties of Fish Mince Protein
Authors: REDDY G. VIDYA SAGAR , SRIKAR L.N.
Published: August 2006

Holding in ice before mincing and freezing pink perch, Nemipterus japonicus, resulted in significant differences in protein solubility (PS), emulsifying capacity (EC), water binding capacity (WBC), cook loss, thaw drip and texture scores. Functional properties correlated with protein solubility. Significant variations in PS, EC, WBC, texture scores, and thaw drip values during frozen storage suggested these properties may be valuable indicators for determining alterations in functional characteristics of fish proteins.
Texture of Raw and Canned Jicama (Pachyrrhizus tuberosus) and Chinese Water Chestnut (Eleocharis dulcis)
Authors: MUDAHAR GURMAIL S. , JEN JOSEPH J.
Published: August 2006

Analyses showed raw jicama had a texture profile between white potato and Chinese water chestnut. Histological examination showed Chinese water chestnut had uniform cell sizes and intercellular spaces with relatively thick cell walls. Jicama had varied cell sizes, irregular intercellular spaces and thin cell walls. Canning reduced crispness of jicama by 65% and that of water chestnut by 20% of that of raw produce. Jicama had endogenous pectin methyl esterase activity. A thermal processing method was developed to produce canned jicama with 70% of the crispness of raw jicama.
Improving Acid Production in Soy‐Based Yogurt by Adding Cheese Whey Proteins and Mineral Salts
Authors: KARLESKIND D. , LAYE I. , HALPIN E. , MORR C.V.
Published: August 2006

Studies were conducted to further elucidate factors responsible for inability of S. thermophilus and L. bulgaricus yogurt culture to produce lactic acid and flavor in soy‐based yogurt made with isolated soy protein and soymilk. Partial replacement of ISP with fresh cheese whey or whey protein isolate, or addition of phosphate and citrate ions resulted in physical stability defects in soy‐based yogurt. They also failed to improve acid and flavor development or provide a 1:1 number concentration ratio of the two culture bacteria types. SM‐based yogurt had lower acid development than ISP‐based yogurt. Addition of commercial sodium caseinate stimulated acid development in SM‐based yogurt.
Gel‐Forming Characteristics and Rheological Properties of Kefiran
Authors: MUKAI TAKAO , WATANABE NAOFUMI , TOBA TAKAHIRO , ITOH TAKATOSHI , ADACHI SUSUMU
Published: August 2006

A water soluble polysaccharide “kefiran” produced by Lactobacillus kefiranofaciens was examined for its gel‐forming and rheological properties. Kefiran (3%) formed gel in the presence of ethanol (4–10%). The gel strength in 8% ethanol was comparable to that of 3% gelatin gel in water. Addition of casein (3%) increased gel strength 1.5–2.0 fold. The unique properties of kefiran may make it a useful food additive.
Maltotetraose Production Using Pseudomonas stutzeri Exo‐α‐Amylase in a Membrane Recycle Bioreactor
Authors: WOO GUN‐JO , McCORD J. D.
Published: August 2006

For a continuous process using maltotetraose (G4)‐forming amylase in a membrane recycle bioreactor (MRB), the enzyme was partially purified to specific activity 21.5 IU/mg protein. The enzyme was stable enough to convert starch into G4 in batch and MRB systems. Optimum conditions in the MRB using hollow fiber with 1,000 molecular weight cut‐off were: substrate concentration 1.0% (w/v), enzyme concentration 70 IU/L reactant, and residence time 83 min. Productivity at steady state under optimized conditions was 0.99 g/L/hr. Excessive residence time decreased product purity by further conversion of G4 to lower molecular weight compounds due to endo‐acting activity of the enzyme.
Turbidity of Beverages with Citrus Oil Clouding Agent
Authors: HERNANDEZ E. , BAKER R.A.
Published: August 2006

Basic principles of light scattering were used to predict turbidity in cloudy beverages for monodisperse and polydisperse systems of suspended citrus oil globules. Predicted values for specific turbidity agreed well with experimental values for diluted citrus oil‐in‐water beverage cloud emulsions. Citrus oil‐in‐water cloud emulsions were prepared with a pressure homogenizer at different pressures (4.1–27.56 kPa). Size distributions obtained for the emulsions fit the long‐normal distribution and the distribution curves became more narrow as pressure of homogenization increased.
Fate of Listeria monocytogenes During Freezing and Frozen Storage
Authors: EL‐KEST SOUZAN E. , YOUSEF AHMED E. , MARTH ELMER H.
Published: August 2006

A cell suspension of Listeria monocytogenes was frozen 30 min at −18°C, or 10 min in liquid nitrogen (LN) at −198°C. Solidification required 15 min at −18°C and ca. 1 min at −198°C. Freezing and storage 1 month in phosphate buffer (PB) at −18°C caused 87% death and 79% injury. These were 54 and 45%, respectively, for cells in Tryptose Broth (TB) at −18°C. Freezing and storage 1 month in LN caused no death or injury of cells suspended in PB, whereas some injury and death occurred in TB. Freezing at −198°C followed by storage 1 month at −18°C resulted in 60% death and 36% injury in PB, and 61 and 44.2%, in TB. Repeated freezing and thawing caused more death/injury than did a single freeze‐thaw cycle.
Total Sulfite in Cellulosics by Ion Exclusion Chromatography with Electrochemical Detection
Authors: REIM ROBERT E.
Published: August 2006

Total sulfite at concentrations ≦ 50 ppm was determined in commercially available thixotropic materials based on methylcellulose (MC) and hydroxypropylmethylcellulose (HPMC) by extraction into an alkaline solution of 5% (w/v) Na2SO4 and subsequent separation by anion exclusion chromatography and electrochemical detection. Results were compared to those obtained by Monier‐Williams distillation which was shown to suffer from low recovery, poor reproducibility and false positive response. Mean sulfite recovery, added at concentrations of 10–50 ppm SO2 was 91 ± 11% based on 12 determinations. Analysis time for the chromatographic method was < 25 min/determination. Aldehydes did not interfere at concentrations < 100‐fold excess.
Chemiluminescent Assay for Glycerol in Wine Using Flow‐Injection
Authors: PUCHADES R. , LEMIEUX L. , SIMARD R.E.
Published: August 2006

A flow‐injection method was developed for the enzymatic determination of glycerol in wines using a reactor containing immobilized glycerokinase and glycerol‐3′‐phosphate oxidase. Hydrogen peroxide from the reaction was monitored by chemiluminescence after reaction with an alkaline reagent containing luminol and hexacyanoferrate (III). Calibration curves were linear between 25 mg/L and 250 mg/L of glycerol for injected volume 29 μL. The method gave satisfactory results compared with a gas‐chromatographic method. No sample pre‐treatment was necessary and a sampling frequency of 30/hr could be achieved.
Nutritional Evaluation of Lipids in Fish from Temperate Australian Waters
Authors: ARMSTRONG SHARYN G. , LEACH DAVID N. , WYLLIE S. GRANT
Published: August 2006

Fatty acid compositions and lipid levels of five common table varieties of marine fish from temperate Australian waters were determined. Nutritionally important values were calculated and compared with those of species from similar waters in the northern hemisphere. P/S and n‐3/n‐6 ratios, and the levels of arachidonic (AA) and docosahexaenoic (DHA) acids in the lipids were comparable for the two, but the Australian species had lower eicosapentaenoic acid (EPA) levels. Oils from Australian fish were shown to have nutritional properties as beneficial as their northern hemisphere counterparts.
Rheological Properties and Adhesion Characteristics of Flour‐Based Batters for Chicken Nuggets as affected by Three Hydrocolloids
Authors: HSIA H. Y. , SMITH D. M. , STEFFE J. F.
Published: August 2006

Time‐dependency, apparent viscosity, shear‐thinning behavior, recovery and adhesion characteristics were determined on 30% solids flour‐based batters containing hydrocolloids (guar, xanthan and carboxymethylcellulose, CMC) at 0.25, 0.5, and 1.0%. Most batters were thixotropic. Batters containing xanthan gum had the greatest apparent viscosity followed in decreasing order by guar gum, CMC and control batters. Apparent viscosity correlated highly positively with batter adhesion characteristics measured on chicken nuggets as coating pickup, overall yield, and cooked yield. Mixer viscometry techniques were useful to follow changes in rheological properties caused by mixing speed and time.
Vitamin A, Electrical Stimulation, and Chilling Rate Effects on Lysosomal Enzyme Activity in Aging Bovine Muscle
Authors: POMMIER S. A.
Published: August 2006

Means of enhancing the rate of aging of bovine meat were investigated to provide some understanding of the tenderization process. Vitamin A was administered to finishing steers, carcasses were electrically stimulated, and longissimus dorsi muscle samples chilled at 2 different rates. Liver cathepsin D, beta‐glucuronidase and hexosaminidase were increased (P < 0.05) with vitamin A supplementation but muscle enzymes were not affected. Chilling rate, electrical stimulation and time significantly (P < 0.05) affected cathepsin D distribution patterns, meat color, Warner‐Bratzler, myofibrillar fragmentation index and collagen data. Troponin‐T degradation was enhanced by aging. Thus, vitamin A can modify liver catheptic enzyme activity but does not affect muscle enzymes at these levels.
Microporous Ultrafiltration of Skim Milk
Authors: WOYCHIK J.H. , COOKE P. , LU D.
Published: August 2006

Membranes with porosities of 100 and 200 nm were used to obtain a 4:1 milk volume reduction. Average micelle diameters determined from electron micrographs were 46 nm (permeate) and 52 nm (permeate) for the 100‐nm‐pore fractions and 46 and 55 nm for the 200‐nm‐pore fractions. The calculated average micellar volumes of the retentate fractions were about twice those of the corresponding permeate fractions. Casein‐whey ratios were 0.7‐0.9 in the permeates and 5.0‐7.7 in the retentates. Higher αs2‐ and lower β‐casein contents were found in the permeate micelles than in the retentates.
Factors Affecting Fat, Cholesterol, and Omega‐3 Fatty Acids in Maine Sardines
Authors: KRZYNOWEK JUDITH , ULJUA DANIEL S. , PANUNZIO LAURIE J. , MANEY RICHARD S.
Published: August 2006

Maine sardines harvested June, July, October, and November were analyzed for moisture, ash, fat, cholesterol, and fatty acids either as whole fish, raw dressed, steam precooked, and after canning in soy oil, menhaden oil, or in the liquid exuded after steam precooking (cookout liquid). Fat content ranged from 5% for juvenile herring sampled June and October to 11% in maturing herring harvested prior to the spawning season in July. All canning liquids contributed to elevated fat content in the finished product. Herring packed in soy oil or cookout liquid had about 90 mg cholesterol/lOOg samples. Herring packed in menhaden oil had 100–115 mg cholesterol/100g. Herring packed in either of the two fish oil solutions contained significantly more ω3 fatty acids and had a greater ratio of ω3:ω6 than those packed in soy oil.
ATPase and Lactate Dehydrogenase Activities in Frozen Stored Fish Muscle as Indices of Cold Storage Deterioration
Authors: NAMBUDIRI D. DAMODARAN , GOPAKUMAR K.
Published: August 2006

The effect of prolonged cold storage on muscle adenosine triphosphatase (ATPase) and lactate dehydrogenase (LDH) activities was studied in a variety of fresh water and brackish water fish. Decrease in enzyme activity was observed in all samples stored frozen (‐ 20°C) over a period of 180 days. Highly significant negative correlation was observed between enzyme activity and frozen storage period with mullet, pearlspot, milk fish and tilapia. Significant linear correlations were observed between decrease in enzyme activities and other biochemical indices and sensory scores. The results indicated that loss of activities of ATPase and LDH in fish muscle was significantly related to early changes in quality of frozen stored fish.
Formation of Transparent Gels of Sesame 13S Globulin: Effects of Fatty Acid Salts
Authors: YUNO‐OHTA NAOKO , MAEDA HIDEO , OKADA MITSUKO , HASEGAWA KIYOZO
Published: August 2006

The physicochemical properties of sesame 13S globulin gels containing fatty acid salts (FAS) were investigated. The softness, water‐holding ability and transparency of the gels markedly increased in the presence of sodium oleate (NaCl18:1) or sodium linoleate (NaC18:2) at a 75 molar ratio to a molecule of the 13S globulin. The effect was not observed by the addition of sodium caprylate (NaC8:0). Scanning electron microscopy showed that a very fine network structure was formed in the gel with 75 molar ratio of NaC18:2. The addition of a suitable amount of FAS having a moderate length and an unsaturated carbon chain could improve the water‐holding ability and transparency of the 13S globulin gel.
Hydrocolloid/Milk Gel Formation and Properties
Authors: XU S.Y. , STANLEY D.W. , GOFF H.D. , DAVIDSON V.J. , LE MAGUER M.
Published: August 2006

Three rheological measurements, as well as cryo‐scanning electron microscopy, were used to study the mechanism of gel formation and structure of a hydrocolloid‐based milk gel. Processing conditions included combinations of pH level and total solids concentration as well as fat content. The first two variables and their interaction influenced gel point, gel strength, viscoelasticity and syneresis; while fat served primarily as a filler of the gel matrix, it also influenced those properties. In model studies of carrageenan and kappa‐casein, calcium ions promoted gelation. Gel microstructure was dictated by processing variables and governed physical properties. The cold‐setting mechanism occurred in three stages, hypothesized to include increased viscosity and molecular alignment, molecular interaction, and aggregation.
Cellulose Derivatives Effects on Gelatinization and Retrogradation of Sweet Potato Starch
Authors: KOHYAMA KAORU , NISHINARI KATSUYOSHI
Published: August 2006

Effects of physically or chemically modified celluloses on gelatinization and retrogradation of sweet potato starch were examined by Theological measurements and differential scanning calorimetry. The mixture of sweet potato starch and four modified celluloses (powdered microcrystalline cellulose, alkaline soluble fibrous cellulose, carboxymethylcellulose and methylcellulose) in the ratio of 9 to 1 was used as a model, because that ratio of starch to cellulose is about the same for sweet potato root. Cellulose derivatives generally did not show important effects on gelatinization temperature and enthalpy of gelatinization. Cellulose derivatives which are not water‐soluble increased starch retrogradation, while water‐soluble methylcellulose unexpectedly prevented retrogradation.
Physicochemical Characteristics of Brown Rice as Influenced by Gamma Irradiation
Authors: SABULARSE V.C. , LIUZZO J.A. , RAO R.M. , GRODNER R.M.
Published: August 2006

Brown rice samples prepared from medium grain (Mars) and long grain (Lemont and Tebonnet) varieties were irradiated at 0, 1.0, 2.0 and 3.0 kGy and analyzed. The amount of solids leached upon cooking increased with increased dose levels indicating the degradation of the rice grain structure. Damaged starch for Mars decreased to the 1.0 kGy level and increased thereafter. Moisture content remained constant between 13% and 14%. Amylose content was not greatly affected by irradiation. Peak viscosity, setback values, final viscosity, viscosity at 50°C, and consistency all decreased with increasing levels of irradiation. As radiation increased, an increase in the yellow color of the rice samples was noted.
Preparation of Starch Phosphates by Extrusion
Authors: CHANG YUNG‐HO , LII CHENG‐YI
Published: August 2006

Physicochemical properties were compared on starch phosphates of cassava and corn, prepared by an extrusion process and by the conventional method, as well as their native starches. Results indicated that for preparing starch phosphates with similar degrees of substitution, the extrusion process required less reagent than the conventional method. The starch phosphates showed similar responses to heat treatment and pH changes. However, the starch phosphates made by extrusion had lower gelatinization temperatures, lower enthalpies and lower paste viscosities than those prepared by the conventional method. This result could be attributed to the high degree of damaged starch in the extruded products.
Isolation of α‐Terpineol Dehydratase from Pseudomonas gladioli
Authors: CADWALLADER K.R. , BRADDOCK R.J. , PARISH M.E.
Published: August 2006

An enzyme which converts the citrus by‐product limonene to α‐terpineol was purified 13‐fold. After cell disruption of P. gladioli, α‐terpineol dehydratase (α‐TD) remained associated with a heterogeneous group of particulate material. α‐TD was partially solubilized by extraction with 10 mM HEPES buffer, pH 7.0 containing 2.0% (w/v) Triton X‐100 and 0.5M sodium trichloroacetate. Two soluble forms existed in 1.0% (w/v) Triton X‐100 with apparent molecular weights of 94,500 and 206,500 daltons.
Restructured Reindeer Steaks: Effects of Flake Size, Phosphate, and Salt on Sensory Properties
Authors: PENFIELD M.P. , SWANSON R.B. , MITCHELL D.S. , RIEMANN M.J. , DORKO C.L.
Published: August 2006

Steaks, fabricated from forequarters from field‐slaughtered Alaskan reindeer, were prepared from meat flaked to two sizes (1.295 and 1.905 cm), with (0.5%) and without phosphate, and with (0.5%) and without salt. Phosphate did not appreciably affect sensory properties. Larger flakes and salt improved quality and acceptability, therefore, additional steaks were fabricated from meat flaked with a larger cutting head (4.064‐cm) and with three levels of salt (0.0, 0.5 and 0.75%). Steaks containing 0.75% salt were less chewy, softer, juicier, and more acceptable than those made with 0.5% salt but did not differ from those containing no salt. Feasibility of producing restructured steaks from reindeer forequarters was demonstrated.
Inhibition of Listeria monocytogenes on Beef Tissue by Application of Organic Acids Immobilized in a Calcium Alginate Gel
Authors: SIRAGUSA GREGORY R. , DICKSON JAMES S.
Published: August 2006

Organic acids added to calcium alginate gels and immobilized on lean beef tissue inoculated with Listeria monocytogenes (Lm) reduced the population significantly more than did acid treatment alone. Lactic acid (1.7% v/v) immobilized in alginate reduced counts by 1.3 log10 units vs 0.03 log unit decrease from the acid treatment alone. Acetic acid (2% v/v) reduced counts 1.5 and 0.25 log units, respectively. Over 7 days, Lm proliferated in samples without acid and/or alginate treatment. Differential counts on selective and non‐selective agars indicated sublethal cellular injury occurred. Alginate coatings did not enhance acid inhibition on fat tissue. Immobilized agents may have potential for raw meat decontamination.
Acetic Acid Action on Beef Tissue Surfaces Contaminated with Salmonella typhimurium
Authors: DICKSON JAMES S.
Published: August 2006

Beef tissue surfaces (lean and fat) were artificially contaminated with Salmonella typhimurium and then sanitized with 2% acetic acid. The reduction in bacterial population by the acid treatment was consistently proportional to the initial inoculum level for both tissue types. Increasing the amount of organic material in the inoculating menstra reduced the bactericidal effects of acetic acid on Salmonella typhimurium on fat tissue, although there was no change in effectiveness on lean tissue. Acid treatment sublethally injured about 65% of the population on both lean and fat tissue, and the residual effects of the acid resulted in a 1 log cycle reduction in bacterial population on fat tissue over 4 hr.
Porcine Somatotropin (PST) Administration to Growing Pigs: Effects on Adipose Tissue Composition and Processed Product Characteristics
Authors: LONERGAN S. M. , SEBRANEK J. G. , PRUSA K. J. , MILLER L. F.
Published: August 2006

Fatty acid profiles and proximate composition were determined at seven carcass locations from 64 pigs. Fatty acid composition was not altered by PST treatment (P > 0.05). The more unsaturated outer layer of subcutaneous fat was present in a greater proportion in the PST‐treated pigs. Adipose tissue fat content was decreased (P < 0.01), whereas percentage moisture and protein was increased (P < 0.01), by PST. Boneless ham characteristics did not differ among treatment groups (P < 0.05). Pepperoni from PST pigs dried more efficiently and was harder than control pepperoni. Bacon from PST pigs contained less fat and was softer than control bacon. Difference in texture of products, particularly bellies for bacon from PST‐treated pigs, seemed to be a result of an altered proximate composition.
Selected Washing Processes Affect Thermal Gelation Properties and Microstructure of Mechanically Deboned Chicken Meat
Authors: YANG T. S. , FRONING G.W.
Published: August 2006

Cooked mechanically deboned chicken meat (MDCM), washed with tap water, 0.5% sodium bicarbonate, sodium phosphate buffer (pH 7.2; ionic strength, 0.1), or 0.1M sodium chloride had increased (P lt;0.05) gel strength compared to unwashed MDCM. The selected washing solutions affected (P lt;0.05) lightness (HunterLab L values) of washed meat, and also had a slight (Plt;0.05) influence on water‐holding capacity and textural properties. These differences were attributed to pH and washing solvent residue in the washed MDCM. Scanning electron microscopy revealed distinct differences between the washed and unwashed MDCM. The washed meat showed a fibrous protein network structure resulting from protein gelation.
Bacteriological Quality of Freshly Processed Broiler Chickens as Affected by Carcass Pretreatment and Gamma Irradiation
Authors: LAMUKA P.O. , SUNKI G.R. , CHAWAN C.B. , RAO D.R. , SHACKELFORD L.A.
Published: August 2006

Chicken carcasses dipped in whey fermented by Streptococcus thermophilus, lactic acid solution or water and irradiated at 2.5 kGy by 60Co were evaluated for bacteriological quality on day‐1, day‐3 and at 3‐day intervals for an 18‐day storage (4°C) period. Unirradiated carcasses treated similarly were used as control. Gram negative bacteria, Yersinia and Campylobacter counts were significantly (p<0.01) lower in irradiated samples, but no significant (p>0.05) differences were observed among the dipping solutions. Salmonellae were completely eliminated in irradiated samples. Whey fermented by 5. thermophilus reduced the proportion of Salmonella contaminated carcasses from 67% to 20%. As evidenced by the bacterial counts the shelf‐life was found to be 15 days for irradiated carcasses compared to about 6 days for the unirradiated samples.
Yield, Lipid, Cholesterol and Fatty Acid Composition of Spent Hens Fed Full‐Fat Oil Seeds and Fish Meal Diets
Authors: AJUYAH A. O. , HARDIN R. T. , CHEUNG K. , SIM J.S.
Published: August 2006

Yield, proximate and fatty acids composition of white and dark meats and whole carcasses were determined in spent hens fed flax or canola seeds, fish meal and a control diet. Live weights and percent carcass cut‐up yield were not affected by the diets fed. However, hens fed flax seed diets contained significantly (P< 0.05) lower levels of cholesterol in the dark meat than the control group. The inclusion of oil seeds, in particular flax seeds in the hens diet, enriched the meats with omega‐3 fatty acids (C18:3ω>3; C20:5ω3; C22:5ω3). Omega‐3 fatty acids enriched poultry meats from spent hens could be useful in the development of “health oriented” further processed poultry products.
Influence of Dairy Proteins on Aspartame Stability in the pH 6–7 Range
Authors: TSOUBELI MENEXIA N. , LABUZA THEODORE P.
Published: August 2006

The effect of three commercial milk protein products on aspartame degradation was studied as a function of temperature (4, 30, 70, 80°C), pH (6 and 7), phosphate buffer concentration (0.01 M/L, 0.1 M/L) and protein (0–3%). Caseinates significantly decreased the pseudo‐first order loss rate at low buffer concentration and higher temperature (70–80°C), whereas the rate was faster in the presence of a casein/ whey mixture. At high buffer concentration, the loss rate was not affected by protein. The protective effect may have been due to either a buffering capacity decrease caused by a protein/aspartame interaction that lowered pH or some unknown protein interaction. At 4 and 30°C, the loss rate was not affected by calcium caseinate.
Formation and Coalescence Stability of Emulsions Stabilized by Different Milk Proteins
Authors: KLEMASZEWSKI J.L. , DAS K.P. , KINSELLA J.E.
Published: August 2006

The volume fraction of oil emulsified, surface area, droplet diameter, and coalescence rates of emulsions stabilized by different milk proteins were studied at protein concentrations of 0.25, 0.5, 1.0, and 2.0% (w/w); pH 4, 5, and 7; and ionic strengths 0.1 and 0.2. The emulsion activity index (EAI) and coalescence stability generally increased with increasing protein solubility and hydrophobicity. The volume fraction of oil emulsified decreased with increasing ionic strength. Coalescence stability correlated with droplet diameter for emulsions stabilized by α‐lactalbumin, β‐lactoglobulin, and sodium caseinate (r2=0.96). With the exception of β‐lactoglobulin‐stabilized emulsions, coalescence stability was largely unaffected by pH.
Isoflavone Aglucones and Volatile Organic Compounds in Soybeans; Effects of Soaking Treatments
Authors: HA EWAN Y. W. , MORR CHARLES V. , SEO AIKO
Published: August 2006

The effect of three different soaking treatments (6 hr in 50°C water; 6 hr in 50°C 0.25% NaHCO3 solution; or 30 min in boiling 0.25% NaHCO3 solution) was studied on the production of the major isoflavone aglucones, daidzein and genistein, and headspace volatile organic compounds including aldehydes, alcohols and furans in soybeans. Both 50° treatments resulted in production of substantial amounts of isoflavone aglucones and headspace volatile organic compounds. The boiling NAHCO3 treatment inhibited production of isoflavone aglucones and lowered total headspace volatile organic compounds.
Molecular Forces in Thermal Association‐Dissociation and Gelation of Legumin from Broad Beans
Authors: ZHENG BAI‐AN , MATSUMURA YASUKI , MORI TOMOHIKO
Published: August 2006

A 0.5% legumin solution when heated showed neither dissociation into constituent subunits of the legumin nor gel formation, but association of the legumin molecules to form soluble aggregates and network‐like structures occurred. Sulfhydryl content of the protein were shown to possibly be responsible for the depression of dissociation. In the 12.5% legumin solution, gelling process and gel properties were affected by reagents such as NaSCN, N‐ethylmaleimide and 2‐mercaptoethanol. Results indicated that hydrophobic interactions and disulfide bonding helped to enhance the gelling process, where contributions of those forces to the rate of soluble aggregate formation and their junctures were notable.
Stability of Ethanol‐Extracted Brown Rice to Hydrolytic and Oxidative Deterioration
Authors: CHAMPAGNE E.T. , HRON R.J.
Published: August 2006

Brown rice kernels extracted with EtOH at 7°C for 60 min were the most stable to lipolytic hydrolysis; free fatty acids (FFA) level in these kernels increased from 1.0–1.4% during 6 mo storage at 36°C. At lower extraction temperatures and times, kernels were less stable to lipolytic hydrolysis. The higher the temperature of extraction, the more susceptible kernels were to oxidative deterioration during storage; extraction time was not a factor. Kernels extracted with recycled EtOH were no more susceptible to oxidation than those extracted with fresh EtOH.
Stabilization of Vitamin A in a Synthetic Rice Premix
Authors: MURPHY PATRICIA A. , SMITH BRENT , HAUCK CATHERINE , O'CONNOR KATE
Published: August 2006

Vitamin A (VA) fortification of rice for developing countries has been attempted by formulating a synthetic rice grain containing VA (called UltrariceR) to be used as a premix with ordinary rice. VA was stabilized with a combination of tocopherol, ascorbic acid and saturated lipids in the formulation. Washing stability of VA was 100%. Cooking stability was greater than 80% retention of VA. ΔH‡ of VA degradation ranged from 4 to 34 kcal/mole depending on Aw and formulation. Entropies ranged from 11 to −79 cal/mol‐deg. ΔH‡ was unchanged averaging 29 kcal/mol. The best t1/2 s for VA were >1 year. Successful stabilization of VA has enabled this premix to be used in clinical and pilot field fortification studies in the Philippines.
Rheological Properties of High‐Methoxyl Pectin and Locust Bean Gum Solutions in Steady Shear
Authors: DA SILVA J.A. LOPES , GONÇALVES M.P. , RAO M.A.
Published: August 2006

The Cross and Carreau flow models described well the shear rate‐apparent viscosity data. The coil overlap parameter, c[η], correlated well with the zero‐shear rate specific viscosities of these mixtures. Experimental values of intrinsic viscosities of the mixtures were in good agreement with the prediction based on an additive model of the individual contributions of the gums. From the results obtained for the mixtures of both polysaccharide solutions at similar viscosity, pH and ionic strength, no significant interactions were detected. Hypotheses for this lack of polymer interaction were developed. Results with such model systems are useful in understanding the relation of composition to the properties of complex food systems.
Validation of Predicted Baking Performance of Muffins Containing Mixtures of Wheat, Cowpea, Peanut, Sorghum, and Cassava Flours
Authors: HOLT SHONA D. , MCWATTERS KAY H. , RESURRECCION ANNA V. A.
Published: August 2006

The performance of seven muffin formulations predicted by computer models to perform similarly to a 100% wheat flour control was studied. An additional formula close to but not within the predicted optimum ranges was included. The nonwheat flours tested were cowpea, peanut, sorghum, and cassava. No significant differences were observed between the formulations for 22 of 31 sensory, physical and compositional characteristics. Two formulations, one containing 25% each of wheat, peanut, sorghum and cassava flours, and the other containing 66.7% wheat and 16.6% each of cowpea and peanut flours differed most from the control. Significant correlations between some sensory attributes and physical and compositional measurements were observed.
Comparative Absorption of Low Molecular Aroma Compounds into Commonly Used Food Packaging Polymer Films
Authors: NIELSEN TIM. J. , JÄGERSTAD I. MARGARETHA , ÖSTE RICKARD E. , WESSLÉN BENGT O.
Published: August 2006

Five polymer films commonly used in food packages were stored in an aqueous solution of 10 apple aroma compounds. Substances absorbed by the polymers were determined by a supercritical fluid extraction/gas chromatography method. Polypropylene absorbed most aromas, more than 2× amounts absorbed by low density polyethylene. Polyamide and polyester absorbed very small amounts of the aromas. Esters and aldehydes were absorbed much more than alcohols. Molecular size also affected absorption, larger molecules being absorbed to a greater extent than smaller ones. For most materials the absorption equilibrium was reached within a week.
Sorption Behavior of Mechanically Mixed and Freeze‐Dried NaCl/Casein Mixtures
Authors: BAKHIT R. M. , SCHMIDT S. J.
Published: August 2006

Adsorption isotherms of mechanically mixed and freeze‐dried mixtures of NaCl/casein at solute percentages of 1, 5, 10, 15, and 20 (wet basis) were obtained over the aw range 0.23–0.927 at 20°C. Experimental isotherm values were compared to those calculated by a mass balance equation. The mechanically mixed samples sorbed additively as predicted by the mass balance equation below 0.755 aw, whereas the freeze‐dried mixtures sorbed more water than predicted (positive interaction) below 0.755 aw, Both types of mixtures sorbed less water than predicted by the mass balance equation (negative interaction) above the saturation aw of the NaCl, 0.755.
Flavor of Cooked, Ground Turkey Patties with Added Sodium Tripolyphosphate as Perceived by Sensory Panels with Differing Phosphate Sensitivity
Authors: CHAMBERS EDGAR , BOWERS JANE R. , SMITH ELIZABETH A.
Published: August 2006

The flavor of cooked, ground turkey patties, with and without sodium tripolyphosphate, was profiled by two panels. One panel had a lower threshold for STP in ground turkey. Flavor profiles indicated that turkey patties without phosphate had more intense protein, serumy, brothy, and metallic character and less intense turkey and soapy character than the samples with phosphate. Both panels found similar characteristics for turkey with added phosphate, although the characteristics had a slightly different order of appearance. The panel with a lower threshold for STP found a more intense soapy character that tended to linger in the phosphate‐treated samples.
Time‐Intensity Study of Prolonged Sweet Stimuli
Authors: LEE WILLIAM E. , BARRICK DENISE M. , WELLING EDWARD S.
Published: August 2006

Prolonged intensity and hedonic (like/dislike) temporal responses and any associated adaptive behavior toward various sweet solutions (sucrose in water) were investigated with specific focus on factors that influenced the transition from “like” to “dislike”. Subjects evaluated the samples using computerized time‐intensity (T‐I) methods to produce sweetness intensity‐time and like/dislike‐time response curves. The higher concentration solutions resulted in adaptive behavior. Also, like‐to‐dislike transition times correlated with sucrose concentration, as did other defined parameters which characterized aspects of the responses, several of which displayed significant cross correlations.
Temperature and NaCl Affect Growth and Survival of Escherichia coli 0157:H7 in Poultry‐Based and Laboratory Media
Authors: CONNER D. E.
Published: August 2006

In tryptic soy broth (TSB) and a poultry extract broth (PB) with 0 to 10% (w/v) NaCl incubated at 37°C, growth of E. coli 0157:H7 was inhibited at 28% NaCl whereas at 10°C, growth was inhibited at 24% NaCl in TSB and at 26% NaCl in PB. The bacterium did not grow at 4°C. Increased NaCl‐sensitivity observed at 10°C was a bacteriostatic effect that was ineffective with increasing incubation temperature. At 10°C, E. coli 0157:H7 was more salt‐tolerant in PB than in TSB, although PB growth rates were lower. Findings suggest that PB may be a more suitable medium for testing E. coli 0157:H7 in poultry products. Cells of E. coli 0157:H7 that were exposed to refrigeration (4°C) and/or NaCl for 24 days did not grow on MacConkey agar with 1% sorbitol.
Moisture Retention and Textural Properties of Ground Chicken Meat as Affected by Sodium Tripolyphosphate, Ionic Strength and pH
Authors: L LOUIS , PAPA C. M. , LYON C. E. , WILSON R. L.
Published: August 2006

Batches of ground chicken meat were mixed with 10% solutions containing 0.0–5.0% sodium tripolyphosphate and sufficient NaCl to adjust the ionic strength (IS) of the solutions from <0.7 to 6.0 at pH 6.5 to 9.5 in a 6 × 4 × 7 factorial experimental design. Patties prepared from the mixtures were evaluated for pH, cooking loss, and objective texture characteristics. Most effects of STPP were attributable to the direct effect of STPP on IS. However the ability of the phosphate to alter textural properties was greater at a pH value near the pKa of the phosphate.
Physical and Sensory Characteristics of Fresh Pork Leg Roasts Cooked at Low Temperatures
Authors: LARSON E.M. , HOLM E.T. , MARCHELLO M.J. , SLANGER W.D.
Published: August 2006

The effects of oven temperatures of 82, 93, 121 and 163°C were studied using 31 fresh pork leg roasts cooked to 74°C in oven bags. Warmed‐over‐flavor (WOF) was measured by sensory analysis after holding 3 hr at 68°C and after holding 24 hr at 2°C and then reheating to 68°C prior to serving. Roasts cooked at 82 and 93°C tended to have less WOF after refrigeration and reheating than roasts cooked at 121 and 163°C. Roasts cooked at 93°C had fewer aerobic mesophilic bacteria than those cooked at 121 and 163°C. In general, objective and sensory perception measurements indicated that roasts cooked at 82 and 93°C were of higher quality.
Detection of Proteolytic Activity in Microorganisms Isolated from Dry‐Cured Ham
Authors: MOLINA IRENE , TOLDRA FIDEL
Published: August 2006

Different assays were tested for the detection of proteolytic activity in both Pediococcus pentosaceus and Staphylococcus xylosus, two major microorganisms isolated from dry‐cured ham. Absence of endopeptidase activity was found even when using raw sarcoplasmic and myofibrillar proteins. However, P. pentosaceus showed strong leucine and valine arylamidase activities while St. xylosus showed a very weak leucine arylamidase activity.
Post‐exsanguination Infusion of Ovine Carcasses: Effect on Tenderness Indicators and Muscle Microstructure
Authors: FAROUK M. M. , PRICE J. F. , SALIH A. M.
Published: August 2006

Lambs were assigned to 3 treatment groups: control (Ctr), infused with 10% volume (by wt) of a tenderizing blend (NCa), and NCa plus 0.015M CaCl2 (WCa). Compared to Ctr and WCa, NCa‐treated samples had lower shear force values (P < 0.05) and higher percent change in myofibrillar fragmentation index (P < 0.05). SDS‐PAGE of infused samples revealed the appearance at 24 hr postmortem of 22‐30 kd protein components. Scanning electron micrographs of NCa myofibrils showed they were more fragmented, fractured, or split and had wider interfibrillar spaces compared to Ctr and WCa. The fracture plane of muscles immediately postmortem was along the endomysial‐sarcolemmal sheath, while at 24 hr postmortem the sheath was weakened enough for the fracture to occur along the surface of the myofibrils.
Mineral Cations Affect Microstructure of Egg Yolk Granules
Authors: CAUSERET D. , MATRINGE E. , LORIENT D.
Published: August 2006

Granule dialysis caused partial release of calcium and breakage of the granular structure. In the presence of sodium chloride, sodium replaced calcium bound to the proteins and destabilized the structure of granules. By contrast, iron binding was not modified by the presence of sodium. EDTA bound all the cations, broke the phosphocalcic bridges and destabilized the structure. On the other hand, the addition of bivalent or trivalent cations at low concentration strengthened the structure which resisted changes in pH or ionic strength. All data showed the importance of ionic bridges (especially phosphocalcic bridges) in the association of LDL, lipovitellin and phosvitin in the form of spherical structures.
Sodium Asocorbate Affects Surimi Gel‐forming Properties
Authors: LEE H.G. , LEE C.M. , CHUNG K.H. , LAVERY S.A.
Published: August 2006

Effect of sodium‐L‐ascorbate (SA) on the gel‐forming properties of Alaska pollock surimi was studied with respect to optimum level, surimi quality, gel setting, vacuum chopping, freeze‐thaw and thermal stabilities, and salt and moisture levels. SA significantly improved gel cohesiveness and sensory firmness of fiberized products with maximum strengthening effect at a 0.2% level. Its effectiveness was directly related to surimi quality regardless of vacuum treatment indicating the unimportance of airborne oxygen. Freeze‐syneresis promoted by ascorbatc during frozen storage was moderated by the use of hydrox‐ypropylatcd‐modified starch.
Semi‐continuous Hydrolysis of Sweet Potato Raw Starch by Chalara paradoxa Glucoamylase
Authors: NODA TAKAHIRO , OHTANI TOSHIO , SHIINA TAKEO , NAWA YOSHIHIKO
Published: August 2006

Effect of preservatives was investigated on semi‐continuous digestion of sweet potato raw starch by Chalara paradoxa glucoamylase which digests both raw and gelatinized starch. Potassium metabisulfite strongly inhibited raw starch digesting activity (RDA) although gelatinized starch digesting activity was only slightly inhibited. Potassium sorbate, among the preservatives examined, showed the weakest inhibition (below 10%) on RDA. In the presence of potassium sorbate, semi‐continuous digestion of sweet potato raw starch in a 20L scale hollow fiber UF membrane pilot reactor proceeded efficiently at 30% (w/v) initial concentration of raw starch at pH 5.0 and 40°C. Glucose production was 5.7 to 6.0 g/hr/L.
Stipe Trimming at Harvest Increases Shelf Life of Fresh Mushrooms (Agaricus bisporus)
Authors: AJLOUNI SAID O. , BEELMAN ROBERT B. , THOMPSON DONALD B. , MAU JENG‐LEUN
Published: August 2006

Trimming the stipe of cultivated mushrooms, Agaricus bisporus, from 35 mm to 5 mm from the cap immediately after harvest resulted in improved shelf life as indicated by reduced browning and slower cap opening. This effect was evident after 3 days storage at 12°C, and became more pronounced after 6 days. Trimming the stipes had no significant effect on postharvest respiration rate or bacterial growth; thus, the shelf life improvement was due to other factors. Stipe trimming reduced the weight (yield) of saleable mushrooms by about 10%; thus, shelf life improvement would need to offset any economic loss to growers to make this practice commercially feasible.