bluuebunny/crossref_metadata_2025 huggingface dataset:
Interactions of Tannic Acid and Catechin with Legume Starches
Authors: DESHPANDE S. S. , SALUNKHE D. K.
Published: August 2006

Model system interactions between five different legume starches (azuki red bean, split yellow pea, small red bean, bush bean, and California kidney bean), potato starch, amylose, and amylopectin and two phenolic compounds ‐ tannic acid and catechin ‐ were investigated. The amounts of tannic acid and catechin associated with different starches and starch fractions at room temperature (21°C) ranged, respectively, from 261‐652 and 123‐586 Mg catechin equivalents/100 mg starch. Heating the systems at 95°C for 30 min decreased the quantities of tannic acid and catechin associated with different starches (151‐417 and 147‐378 μg catechin equivalents/100 mg starch of tannic acid and catechin, respectively). Bound tannic acid and catechin decreased the in vitro digestibility of the starches.
Pectin‐Protein Interaction in Tomato Products
Authors: TAKADA NORIHISA , NELSON PHILIP E.
Published: August 2006

The pH influenced the viscosity of a model system of tomato product which consisted of citrus pectin and bovine serum albumin. The viscosity change was completely reversible depending on the pH. The same pH effect was observed in tomato products. Since the amino acid compositions of proteins suggest that the electrostatic property of water‐soluble protein fraction from tomato juice can be similar to that of bovine serum albumin, the comparison of pH effects indicates that pectin‐protein interaction may be involved in consistency of tomato products. Denaturation of protein may result in a decrease in the serum viscosity during processing.
Characterization of Soluble and Bound Peroxidases in Green Asparagus
Authors: WANG Z. , LUH B. S.
Published: August 2006

Soluble and ionically bound peroxidases were extracted from green asparagus with 0.05M sodium phosphate (pH 7.0) and the same buffer containing 1.0M NaCl, respectively. The two forms of peroxidase have been purified 237 and 53 fold, respectively, through ammonium sulphate fractionation, and successive chromatography on Sephacryl S‐200 and ConA Sepharose 4B columns. Eleven isoenzymes with different pI values were detected from the soluble form using isoelectric focusing and eight from the ionically bound form. The two forms of perooxidase showed a similar optimum pH range of 4.2–5.0 using three kinds of hydrogen donor with different buffers. The optimum temperature of the two peroxidase forms at pH 4.5 was around 50°C. Heat inactivation of both forms at 70° and 90°C was observed to be biphasic.
Comparison of Four Methods for Determining Protease Activity in Milk
Authors: KWAN K. K. H. , NAKAI S. , SKURA B. J.
Published: August 2006

Four methods (absorbance at 280 nm; the Lowry method; the fluor‐escamine method, and the trinitrobenzenesulfonic acid method) for determining hydrolysis of milk proteins were compared. Each method was applied to the trichloracetic acid soluble fraction of milk protein, which had been digested with trypsin for various periods of time. Detectability was measured as the ratio between standard error of estimate and slope calculated from the linear regression analysis of Deming for cases when both variables were subject to error. Although it was nondimensional, the detectability thus calculated was simple and reliable for comparing assay methods which were based on different analytical principles. Detectability as well as the detection limit measured according to Schwerdtfeger showed that, of the methods compared, the fluorescamine method was most reliable and sensitive.
Measurement of Glycosylated Vitamin B6 in Foods
Authors: KABIR HOSSEIN , LEKLEM JAMES , MILLER LORRAINE T.
Published: August 2006

To examine the levels of glycosylated vitamin B6 in 22 foods, each food was stirred for 2 hr at pH 6.8 and then incubated for 2 hr at pH 5.0 and 37°C with β‐glucosidase (60 units per g food). Vitamin B6 content of foods was measured microbiologically before and after enzyme treatment as well as with acid hydrolysis. Animal products contained no measurable amount of glycosylated B6. Grains and legumes generally had a high level of this bound form (6–57% of the total vitamin B6). Of the fruits analyzed, orange juice had the highest level of glycosylated vitamin B6 (47%). Among fresh vegetables studied, raw carrots had the highest level (51%). For broccoli and cauliflower, the glycosylated value was higher for the processed food as compared to the raw food.
Iron‐Enriched Bread: Interaction Effect of Protein Quality and Copper on Iron Bioavailability
Authors: RANHOTRA GUR , GELROTH JANETTE , NOVAK FRANCES , BOCK ANN , BOHANNON FAUSTINA
Published: August 2006

These studies examined the bioavailability of iron in iron‐enriched breads. The test breads also contained added protein in the form of gluten, soy or nonfat dry milk. Bioavailability was assessed based on net hemoglobin synthesis in rats initially made iron deficient and then fed bread‐based diets containing 38.5 ppm iron (NRC requirement for rat, 35 ppm) and 3.75, 5.00, or 6.25 ppm copper (NRC requirement for rat, 5 ppm). More hemoglobin was synthesized on milk‐supplemented (83 mg/mg iron) and on soy‐supplemented (85 mg/mg iron) bread diets than on gluten‐supplemented (59 mg/mg iron) bread diets. Copper appeared to have no influence on hemoglobin regeneration or on hepatic iron accumulation under the conditions of this experiment.
Sunflower Hull Flour as a Potential Dietary Fiber Supplement
Authors: DREHER M. L. , PADMANABAN G.
Published: August 2006

Confectionery hull flour (CHF) and oilseed hull flour (OHF) were evaluated as potential dietary fiber supplements. Analyses included: proximate analyses, neutral detergent fiber, acid detergent fiber, acid detergent ligrdn and buffered acid detergent fiber, water‐ and oil‐holding capacity, pH, cation exchange capacity, emulsifying activity (EA), Gardner color values, and sensory evaluation. CHF (90.7% NDF) was slightly higher in dietary fiber than OHF (83.4%). Sunflower hull flours had a relatively high cation exchange capacity, equivalent to lettuce. Sunflower hull flours were highly variable in color and EA. There was no significant difference in aroma of muffins made with hull flour or wheat bran but differences did exist in appearance, flavor and texture. Sunflower hull flour showed potential as a dietary fiber supplement but its exact physiological effects have not yet been established.
Textural and Rheological Properties of Cooked Potatoes
Authors: LEUNG H. K. , BARRON F. H. , DAVIS D. C.
Published: August 2006

Cooked potato samples of different cultivars and specific gravities were analyzed for textural and rheological properties by sensory evaluation, texture profile analysis (TPA) and stress relaxation tests. Mealiness was correlated with the product of cohesiveness and adhesiveness, but not with other TPA parameters. Stress relaxation tests of cooked potatoes yielded a Maxwell model consisting of two viscous and three elastic elements. One of the elastic moduli was correlated with mealiness. Hardness by sensory evaluation correlated well with hardness and fracturability by TPA, and with the three elastic moduli in the relaxation model.
Effects of Rennet Treatment and Water Content on Thermal Conductivity of Skim Milk
Authors: HORI TOMOSHIGE
Published: August 2006

Effective thermal conductivities of skim milk and skim milk curd over a moisture range of 60–95% were measured by the hot wire method. The measured thermal conductivity of skim milk decreased significantly with change in structure through rennet treatment at 30.0°C; the intrinsic thermal conductivity of solids content was determined on the basis of the series model to be 0.346 W/mK for skim milk and 0.338 W/mK for skim milk curd. The relationship between the water content and effective thermal conductivity of the specimens was described by using a single parabolic formula. The deviations of empirical values based on this formula related to the experimental ones were 0.31 ± 0.30%.
Antibotulinal Activity of Methyl and Ethyl Fumarates in Comminuted Nitrite‐Free Bacon
Authors: HUHTANEN C. N.
Published: August 2006

Mono‐ and dimethyl and ethyl esters of fumaric acid were evaluated for their antibotulinal efficacy in cans of comminuted nitrite‐free bacon. At 0.125%, all were equal or superior to 120 ppm nitrite in preventing toxin formation in cans incubated at 30°C for 8 wk. No cans swelled or became toxic when mono‐ or dimethyl fumarate was added. With monoethyl fumarate, two cans out of twenty swelled but were nontoxic. The least effective ester was diethyl fumarate but its activity was equal to that of 120 ppm nitrite.
Shear Force Values for Steaks from the Semitendinosus Muscle of Pre‐Rigor Leg‐Twisted Beef Carcasses
Authors: ODUSANYA S. O. , OKUBANJO A. O.
Published: August 2006

The imposition of leg‐twist treatment to intact beef carcass sides increased the mean, mode and median of the shear values of cooked semitendinosus muscle. Steaks from treated sides were uniformly tougher than steaks from nontreated sides. In both treated and nontreated sides, the anterior end of the muscle was tougher than the posterior end.
Effect of Chitin as Coagulating Aid on Protein Yield, Composition and Functionality of Tomato Seed Protein Concentrates
Authors: LATLIEF SARA J. , KNORR DIETRICH
Published: August 2006

The effectiveness of chitin as coagulating aid, protein coagulants and coagulation temperatures in recovering tomato seed proteins, and their effect on composition and emulsion properties of tomato seed protein concentrates (TSPC) were investigated. Citric acid, hydrochloric acid, or a mixture of citric acid and hydrochloric acid were used and chitin addition ranged from 0 to 1.0% (protein basis). Coagulation temperatures employed were 25°C, 60°C or 95°C. Samples with no chitin added resulted in significantly (P < 0.05) lower protein yields than samples with chitin addition. Ash content of the TSPC was significantly (P < 0.05) affected by chitin addition and coagulation temperature. Lowest crude fat content was obtained with citric acid at 25°C. Lowry protein and total nitrogen was highest without chitin addition. Samples coagulated at 25°C showed highest emulsion ability and emulsion stability. The least stable emulsions were produced with hydrochloric acid. Chitin addition did not affect emulsion properties.
Inherent Variability in the Efficacy of the USDA Raw‐Pack Process for Home‐Canned Tomatoes
Authors: MONTVILLE THOMAS J. , CONWAY LUCILLE K. , SAPERS GERALD M.
Published: August 2006

Studies of the USDA raw‐pack process for home‐canned tomatoes, using Bacillus licheniformis spores as the target organisms, revealed that water bath size and canning load did not affect heat penetxation rates in pint jars of tomatoes. However, because decreases in the water bath size and canning load shortened the come‐up time and, as a result, lowered the maximum cold‐spot temperature; the calculated process lethalities were lessened. Properly executed canning runs which varied in water bath size, amount of water in the bath, and load size produced calculated lethalities ranging between 1 and 7 log reduction.
Quality Improvement of Canned Mung Bean (Vigna radiafa) Sprouts
Authors: BUESCHER R. W. , CHANG J. S.
Published: August 2006

The effect of calcium, ascorbic acid, citric acid and EDTA on texture, color and flavor of mung bean sprouts canned as a low‐acid food (pH > 4.6) and the effect of acidification by acetic, citric, gluconic, lactic and malic acids on quality of mung bean sprouts canned as an acid‐food (pH < 4.6) were examined. Either the addition of calcium or acidification enhanced texture. Texture of products canned as low‐acid food increased with decreasing pH. Color was markedly improved by either EDTA combined with ascorbic acid or acidification. Processing in plain (uncoated) cans or treatment with acetic acid was detrimental to flavor. Overall, the best low‐acid food product was obtained by the combination of calcium, ascorbic acid, citric acid and EDTA while the best acid‐food product was obtained by acidification with gluconic acid.
Studies on Expanded Rice. Optimum Processing Conditions
Authors: CHINNASWAMY R. , BHATTACHARYA K. R.
Published: August 2006

Optimum conditions of parboiling, milling and puffing for making expanded rice were studied on a small laboratory scale. Optimum puffing was obtained by heating milled parboiled rice at a moisture content of 10.5–11% with 15 times its weight of fme sand at 250°C for 10–11 sec. Raw and mildly parboiled rice gave minimal expansion, which increased with increasing severity of parboiling up to a steam pressure of 1.5 kg/cm2. However, rice parboiled by heating with sand (250°C, 2.5 min) expanded best. Starch retrogradation after parboiling reduced expansion, as did cracked and broken grains and insufficient milling of the rice. Addition of salt increased expansion. Expansion initially increased and then decreased with increasing age of paddy after harvest.
Dynamic Optimization of Dehydration Processes: Minimizing Browning in Dehydration of Potatoes
Authors: MISHKIN MARTIN , SAGUY ISRAEL , KAREL MARCUS
Published: August 2006

A simulation‐optimization procedure based on the complex method was used to determine optimal drying schemes for minimizing browning during dehydration of white potatoes. Browning kinetics were obtained from the literature, and the heat and mass transfer characteristics of the potatoes were based on experimental data obtained previously. The optimal dryer temperature control path reduced the temperature while the sample disk moisture content was in the range 0.1–0.2 g/g‐solids, where the browning rate is maximal. Excellent agreement was obtained between optimal dryer temperatures based on local moisture and those based on average moisture contents.
Sensory Evaluation of High Vacuum Flame Sterilized Clingstone Peaches, Using Ranking and Signal Detection Measures with Minimal Cross‐Sensory Interference
Authors: O'MAHONY M. , BUTEAU L. , KLAPMAN‐BAKER K. , STAVROS I. , ALFORD J. , LEONARD S. J. , HEIL J. R. , WOLCOTT T. K.
Published: August 2006

Seven peach varieties were canned conventionally with added syrup or added water and using high vacuum flame sterilization (HVFS) with and without added syrup. The treatments were assessed for sweetness, sourness, odor intensity, darkness of color, firmness by bite and firmness by visual appearance, using ranking and R‐index measures. Cross‐sensory interference was minimized by the excluding or reducing of the effects of inappropriate senses. Conventionally canned peaches were less firm to the bite but this did not correspond with visual appearance of firmness. Peaches canned with added syrup tended to be sweeter and less sour. Color and odor differences were less clear cut. Comparisons were also made with fresh peaches.
Hydrolysis and Ultrafiltration Treatment to Improve the Nutritive Value of Rapeseed Proteins
Authors: LACROIX MONIQUE , AMIOT JEAN , BRISSON GERMAIN J.
Published: August 2006

In order to improve their nutritive value, rapeseed proteins were hydrolyzed with pepsin (60 min) and trypsin (120 min). The hydrolysate was centrifuged at 10,000 ×g for 10 mln and the soluble fraction was ultrafiltered with a Romicon cartridge having a molecular weight cut‐off of 10,000 daltons. Nutritional experiments with rats demonstrated that the net protein ratios obtained with rapeseed hydrolysate and ultrafdtrate (4.68 and 4.55 respectively) were higher (P < 0.05) than that of casein (4.40). The protein digestibility of the ultrafiltrate (90.3) was not different from that of casein (91.1) but higher than that of raw rapeseed flour (81.9). These hydrolysis and ultrafiltration treatments improved the nutritive value of rapeseed proteins by permitting the isolation of by‐products of a molecular weight lower than 5000 daltons.
Effect of Soda Leavening on Phytic Acid Content and Physical Characteristics of Middle Eastern Breads
Authors: FARIDI H. A. , FINNEY P. L. , RUBENTHALER G. L.
Published: August 2006

The effect of soda (sodium bicarbonate) as a leavening agent on pH, phytic acid hydrolysis and physical quality of a fermentation model system and two popular Middle Eastern breads, Iranian taftoon and Pakistani naan (Arabic) were studied. Supplementing 0.2 and 0.4% soda invariably decreased phytic acid hydrolysis. In sour starter supplemented dough, phytic acid was reduced by 82% after 3 hr. However, when 0.4% soda and sour starter were added loss of phytic acid did not exceed 29%. Supplementing soda in taftoon and naan bread formula significantly lowered phytic acid hydrolysis during fermentation. Soda had no apparent improvement on physical quality of breads but increased the dough water absorption and lengthened the mixing time.
Effect of Potassium Sorbate and Vacuum Packaging on the Quality and Microflora of Dry‐Cured Intact and Boneless Hams
Authors: KEMP J. D. , LANGLOIS B. E. , FOX J. D.
Published: August 2006

Intact and boneless hams were dry‐cured and aged with and without potassium sorbate or vacuum packaging. Sorbate had no effect on yield but dry sorbate generally improved panel scores in boneless hams. Vacuum packaging eliminated further weight loss, decreased visual appraisal scores in intact hams but had little effect on sensory scores. After 3 months of aging, aerobic and staphylococci counts were as much as 7 logs lower in nonvacuum packaged controls than in either nonvacuum or vacuum packaged sorbate treated intact hams. Counts within all vacuum packaged groups were similar. Yeast and mold counts were lower in sorbate treated than in non‐sorbate treated vacuum packaged hams. After aging, coagulasenegative staphylocci were the predominant species.
Continuous Lactose Hydrolysis in Fixed‐Bed and Expanded‐Bed Reactors Containing Catalytic Resins
Authors: CHEN H. C. , ZALL R.R.
Published: August 2006

Kinetics studies of lactose hydrolysis in a continuous fixed‐bed column reactor containing catalytic resins showed that the reaction was first order. The Q10 value between 85 and 95°C was 4.08 and estimated activation energy was 36.9 Kcal/mole. Operational difficulties occurred when deproteinated whey was used as the substrate for the above process. Therefore, an expanded‐bed process was developed to hydrolyze deproteinated whey. Acid was also added to the deproteinated whey to enhance the functionality of catalytic resin. The modified process improved reaction rate and facilitated process operation. At 95°C, 99% of the lactose in whey was hydrolyzed within 3 hr of residence time when the substrate was acidified with concentrated nitric acid to a final acid concentration of 0.6N.
Impedimetric Determinaton of Total, Mesophilic and Psychrotrophic Zounts in Raw Milk
Authors: FIRSTENBERG‐EDEN R. , TRICARICO M. K.
Published: August 2006

A rapid impedimetric determination for total, mesophilic and psychrotrophic counts in raw milk showed correlations (between impedance detection times and standard plate counts) of ‐0.96, ‐0.95, and 0.96, respectively. Mesophiles were most often seen as the predominant population, the impedimetric method allowed for these samples containing above 1.0 × 105 CFU/ml to be screened out within 4 hr. Psychrotrophic levels of 1 × 105 CFU/ml and above were screened within 21 hr, while total concentration of samples containing above 1 × 105 CFU/ml were screened within 16 hr.
Collagen as the Major Edible Component of Jellyfish (Stomolophus nomural)
Authors: KIMURA S. , MIURA S. , PARK Y‐H.
Published: August 2006

The mesogloea and skin of a common edible jellyfish, Stomolophus nomurai, were characterized with respect to amino acid composition and compared with a commercially salted jellyfish. Then the mesogloea was digested with pepsin at 3°C for 48 hr and its solubilized protein was isolated and subjected to biochemical analyses. These composite results have shown that the major edible component of jellyfish was the connective tissue protein, collagen, characterized by its high content of hydroxylysine and its glycosides.
Effect of Locust Bean Gum and Selected Sweetening Agents on Ice Recrystallization Rates
Authors: HARPER E. K. , SHOEMAKER C. F.
Published: August 2006

A methodology has been devised to study the effects of sweeteners and a stabilizer on the rate of ice recrystallization. Aqueous solutions of sucrose, corn syrup (62 DE), and high fructose corn syrup with locust bean gum, and solutions of corn syrup with varying levels of locust bean gum were also studied. Microprocessor controlled time‐temperature experiments were performed with each sample. Average ice crystal size was measured after each heating/ cooling cycle. Effect of viscosity on ice recrystallization growth rates was also studied. This methodology is an improved technique for providing temperature control during fluctuating temperature studies. Concentration of locust bean gum showed no correlation to ice recrystallization rates. The choice of sweetener used in the aqueous solution was found to affect the rate of ice recrystallization.
Volatile Constituents of the Essential Oil of Kumquat
Authors: KOYASAKO A. , BERNHARD R. A.
Published: August 2006

In this study 120 compounds were found and 71 volatile compounds were identified in the essential oil of kumquat. A simultaneous distillation/extraction technique was used to obtain the essential oil from the fruit. Individual compounds were identified by means of Kovats retention indices on polar and nonpolar columns and mass spectral data. Some 13 sesquiterpenes, 8 terpenes, 11 alcohols, 1 ketone, 8 aldehydes and 13 esters were identified in kumquat oil for the fist time. Limonene was the most abundant compound comprising 93% of the whole oil.
Two Dimensional Heat Conduction in Food Undergoing Freezing: Predicting Freezing Time of Rectangular or Finitely Cylindrical Food
Authors: HAYAKAWA KAN‐ICHI , NONINO CARLO , SUCCAR JORGE
Published: August 2006

Since there was no procedure available for estimating freezing time of rectangular or finitely cylindrical food through manual calculations, the present study was initiated to develop such a procedure. For this development, our computerized model was used together with statistical techniques. A design for screening tests was used to identify eight dimensionless groups, which influences significantly the freezing rate, out of 22 independent groups. Among the eight groups, only two were related to the thermophysical properties of food. Through the joint application of a central composite design of experiments and of the computerized model, algebraic formulae containing the eight significant groups were derived for the freezing time estimation. Their validity was verified through experimental freezing processes.
Sensory Evaluation of Lamb After Growth of Yeasts at −5°C
Authors: WINGER R. J. , LOWRY P. D.
Published: August 2006

Cryptococcus laurentii var laurentii was inoculated at various densities onto lamb loins, which were then frozen and stored at 5°C for 10 wk. During storage, yeast numbers increased by two log cycles. Loin samples that included yeast‐bearing surfaces were prepared for evaluation by a trained taste panel. No foreign flavors associated with high yeast numbers could be discriminated by the panel.
Effect of Irradiation on the Inhibition of Clostridium botulinum Toxin Production and the Microbial Flora in Bacon
Authors: ROWLEY DURWOOD B. , FIRSTENBERG‐EDEN RUTH , POWERS EDMUND M. , SHATTUCK G. EDGAR , WASSERMAN AARON E. , WIERBICKI EUGEN
Published: August 2006

The effect of irradiation (0.5, 1.0, 1.5 Mrad) on the microbiological safety and stability of temperature‐abused (27°C, 60 days) bacon cured with' 1.5% NaCl, 0.25% sucrose, 0.3% Na5P3O10 0.055% Na‐erythorbate, with or without NaNO2 (40 μg/g) was determined. Unioculated bacon (120 μG/g NaNO2/g) had a sour odor within 13 days, and, if inoculated with ca. 2 C. botulinum spores/g, 73% of the samples became toxic within 60 days. Irradiation with 0.5 Mrad prevented spoilage of uninoculated bacon by virtue of reducing the aerobic plate count to <1.0/g; irradiation with 1.0 Mrad sterilized bacon. Pouches of bacon, inoculated with C. botulinum spores (2 spores/g), swelled and became toxic; development of swelling and toxicity was delayed by incorporation of NaNO2 (40 μg/g) or by irradiation with 0.5 Mrad. Irradiation with 1.0 Mrad decreased the number of swollen and toxic pouches. Irradiation with 1.5 Mrad prevented swelling and toxicity of bacon inoculated with 2 spores/g.
Use of Vacuum During Formation of Meat Emulsions
Authors: TANTIKARNJATHEP KAMCHORN , SEBRANEK JOSEPH G. , TOPEL DAVID G. , RUST ROBERT E.
Published: August 2006

Meat emulsion formation under vacuum was studied in a model system and in a sausage emulsion. Sarcoplasmic and myofibrillar extracts from beef and pork infraspinatus muscle were used to compare emulsification of vegetable oil with or without vacuum. Vacuum treatment permitted more oil to be emulsified by all protein extracts. The proportional increase was greater for water‐soluble than for salt‐soluble extracts. Sausage emulsion was evaluated using frankfurters prepared in a vacuum chopper with or without vacuum. Product stability was improved by application of vacuum only for the entire chopping procedure. Cured color development was more rapid and more complete in the vacuum treatment. Without vacuum chopping, frankfurters showed more obvious cavitation and less density, confirming presence of air within the emulsion.
Effect of Soy Flour, Soy Protein Concentrate and Sodium Alginate on the Textural Attributes of Minced Fish Patties
Authors: ROCKOWER R. K. , DENG J. C. , OTWELL W. S. , CORNELL J. A.
Published: August 2006

A mixture response statistical design was used to investigate the textural attributes of minced fish patties. Patties formulated with pollock were significantly firmer than those made from turbot and pollock blends or from turbot alone. Breakpoint values and firmness scores were negatively correlated with flavor and acceptability scores indicating that as patty firmness increased general acceptability declined. Higher acceptability for softer patties formulated with more turbot were attributable to the higher fat content. Increasing the soy protein levels and decreasing alginate content increased patty firmness regardless of fish composition. The patty formulation with maximum predicted acceptability was 78% turbot, 11% soy flour, and 11% soy protein concentrate.
Bisulfite Suppression of Fish Aromas
Authors: JOSEPHSON D. B. , LINDSAY R. C. , STUIBER D. A.
Published: August 2006

ADDITION of sodium bisulfite (100–500 ppm) to water extracts of slime from fresh and oxidized whitefish (Coregonus clupeaformis) caused immediate and nearly complete suppression of fishy aromas. Chromatograms of headspace volatiles revealed the selective removal of influential carbonyl compounds through the formation of bisulfite addition products. Poaching whitefish fillets in bisulfite solutions (200 ppm) also yielded significantly suppressed oxidized and fishy flavors compared to similar untreated samples when evaluated by sensory analysis. Odor assessments of pH‐adjusted (3—12) water extracts of fish slime showed that bisulfite was active over the entire pH range, but was most effective in suppressing aromas over the mid‐ranges (5.5–8.5).
Starch‐Sugar Transformation During Banana Ripening: The Behavior of UDP Glucose Pyrophosphorylase, Sucrose Synthetase and Invertase
Authors: TERRA N. N. , GARCIA E. , LAJOLO F. M.
Published: August 2006

Starch concentration, sequence of appearance of sucrose, glucose and fructose and activity of some enzymes of sucrose synthesis were followed during ripening of preclimacteric bananas (Musa acuminatd). As starch was degraded sucrose content increased and preceded formation of glucose and fructose. At the same time, while UDP‐glucose pyrophosphorylase activity remained constant, activity of sucrose synthetase and invertase increased. The observed sugar and enzyme changes indicated that starch to sucrose transformation via glucose‐1‐phosphate‐UDP‐glucose may be an important mechanism for starch disappearance during ripening. The hypothesis was confirmed with thin banana slices infiltrated with [14C(U)]glucose‐1‐phosphate: the label was incorporated into sucrose three times faster for climacteric than for preclimacteric fruits. Pyrophosphorylase activity and climacteric induced activation of sucrose synthetase could be inhibited by protein and nucleic acids synthesis inhibitors.
Computerized Image Analysis of Surface Browning of Pizza Shells
Authors: UNKLESBAY K. , UNKLESBAY N. , KELLER J. , GRANDCOLAS J.
Published: August 2006

An objective measurement using computerized image analysis techniques was developed for determining the level of brownness on the bottom surface of pizzas. Infrared heat processing (327/332°C) was investigated for both wheat and soy‐fortified, wheat pizza shells. Moisture, fat, total and unavailable lysine were determined by chemical analysis. A linear function was developed which shows promise for predicting the available lysine content for soy‐fortified shells. This function utilizes information taken from the image of the bottom of the pizza. This technique could be useful in cases where a rapid, nondestructive test for available lysine in baked dough is needed.
Sensory Attributes of Corn Tortillas with Substitutions of Potato, Rice, and Pinto Beans
Authors: FERIA‐MORALES ALEJANDRO M. , PANGBORN ROSE MARIE
Published: August 2006

Corn tortillas were prepared with substitutions of 12, 24, and 36% of two varieties of potato, 10, 20, and 30% of rice, and 5, 10, and 15% of pinto beans. Trained judges developed descriptors for appearance, aroma, manual and oral texture, flavor, and aftereffects, to quantify differences from the all‐corn reference. Up to 24% of either variety of potato, 30% of rice, and 15% beans could be substituted before undesirable sensory differences were detected. Potato improved texture, producing a softer, more flexible tortilla. Beans produced a less yellow, harder tortilla, and rice caused few sensory changes. Sensory texture compared well with Instron hardness and elongation measurements. Protein and lysine were unchanged by potato, increased by bean, and slightly decreased by rice substitution.
Some Functional and Utilization Characteristics of Sesame Flour and Proteins
Authors: DE PADUA M. RIVERO
Published: August 2006

Sesame defatted flour was prepared from dehulled seeds and the proteins extracted by isoelectric precipitation from an alkaline suspension of the flour. Temperature and pH effects on viscosity of a protein dispersion were measured using a Brookfield viscometer. Emulsifying capacity and emulsion stability were measured in mayonnaise and meat‐type emulsions, respectively. Sesame flour was texturized by a simple method to produce a ground meat‐like product with a hydration capacity of 380–440%. Sensory evaluation of meat loaves with 0–40% meat replaced by hydrated textured defatted sesame flour indicated no significant difference between samples. Viscosity of sesame protein dispersions at 90°C increased with increasing pH. The proteins did not form a self‐supporting gel. Their emulsifying capacity proved to be relatively high when compared with traditional proteins.
Effect of Nitrogen Flushing on the Production of Proteinase by Psychrotrophic Bacteria in Raw Milk
Authors: MURRAY S.K. , KWAN K.K.H. , SKURA B.J. , McKELLAR R.C.
Published: August 2006

Raw milk was flushed with 100 ml N2 min ‐1 during storage at 4°C. Microflora (total psychrotrophs, proteolytic psychrotrophs, lactic acid bacteria) in nitrogen‐flushed milk exhibited a longer lag phase and slower growth rates than those in milk stored aerobically at 4°C. Although proteolytic psychrotrophs grew in nitrogen‐flushed milk, proteinases could not be detected in these milk samples. Proteinase assays and electrophoresis showed extensive proteolytic activity and hydrolysis of β‐casein in control milk but no detectable casein degradation in nitrogen‐flushed milk, even after storage for 18 days at 4°C. This study shows the potential of controlled atmosphere storage of raw milk for inhibition of the accumulation of proteolytic enzymes from psychrotrophic bacteria.
Lability and Reactivity of Nonheme Protein‐Bound Nitrite
Authors: ITO T. , CASSENS R. G. , GREASER M. L. , LEE M. , IZUMI K.
Published: August 2006

Nitrite treated nonheme protein was separated from the free nitrite of the reaction mixture by Sephadex G‐15 column chromatography. Spectral analysis (absorbance at 330 nm) indicated that tryptophyl residues of the protein had been modified with the NO group. The protein‐nitrite complex was not stable, decomposing faster at lower pH and higher temperature. As the extent of the decomposition increased with time, an increasing amount of nitrite was detected by the AOAC method, indicating that the Griess reagent reacted with nitrite after it was regenerated from the NO group. When myoglobin was incubated with the nitrosated protein, nitrosyl hemochrome could be extracted from the reaction mixture in the presence of ascorbic acid. The results indicate the potential reversibility of the protein‐nitrite reaction.
The Behavior and Stability of Iron‐Ascorbate Complexes in Solution
Authors: GORMAN J. E. , CLYDESDALE F. M.
Published: August 2006

The thermodynamic stability constants for ferric and ferrous ascorbate complexes, change in net redox potential with pH, and efficacy of bathophenanthroline as an iron reagent in the presence of ascorbate were determined. The stability constants for the ferric and ferrous ascorbate complexes were found to be in the range 1.90 × 103to 2.61 × 104and 7.69 × 10‐3to 6.95 × 10‐2, respectively. The stability of ferric ascorbate over a wide range of pH values suggests its potential use as an iron additive in foods. Redox potential decreased with an increase in pH. Bathophenanthroline analysis of these solutions for free iron proved to have limitations in the presence of ascorbate.
Predicting the Texture of Liquid and Melting Semi‐Solid Foods
Authors: KOKINI JOZEF L. , CUSSLER E. L.
Published: August 2006

Magnitude estimations of a variety of dairy foods show that sensory assessments scores of “creaminess” can be predicted from scores of “smoothness” and “thickness”. The empirical equation found for these predictions is very close to that found earlier for model solutions. Assessments of “smoothness” can be related to instrumental measurements of contact friction. Assessments of “thickness” for melting foods are related to estimates of shear stresses in the mouth generated during the melting of foods.
A Deviant Heat Process Applied to Canned or Packaged Liquid Food
Authors: HUANG FUNAN , HAYAKAWA KAN‐ICHI
Published: August 2006

A new procedure was developed for predicting the correction factor of a deviant thermal process applied to canned or packaged convection heating food. This development was accomplished through a combined application of a mathematical model for estimating process lethality and statistical procedures. Through a dimensional analysis of the mathematical model it was found that there were nine independent dimensionless parameters required to define uniquely correction factors. The influence of each parameter was determined by applying a statistical design of screening tests. Of the nine dimensionless parameters, only two parameters, which contained a magnitude of drop in heating medium temperature, duration of this drop, the slope index of thermal death time curve, and the slope index of heating curve influenced significantly the correction factor. Those of no significant influence included initial food temperature, retort temperature, cooling water temperature, drop location, and normal processing time. A simple polynomial equation was obtained for predicting the correction factor by applying a central composite design of experiments and a statistical regression analysis. The reliability of this equation was verified through heat transfer experiments by using canned distilled water, 0.1% bean gum aqueous solution, and tomato juice.
Ascorbic Acid and Folic Acid Content and Sensory Characteristics of Dehydrated Green Peppers
Authors: KUZNIAR ANNA , BOWERS JANE A. , CRAIG JEAN
Published: August 2006

Moisture content, water activity, ascorbic and folic acid content, and color of blanched and unblanched green peppers, dried for 8 or 9 hr at 60°C or 12 hr at 49°C, were determined before and after 8 wk storage at room temperature. Sensory characteristics of the peppers were evaluated after storage. Blanching influenced ascorbic acid content, color, firmness, and intensity of green pepper, sweet and bitter flavor. Time and temperature of drying influenced water activity and some texture attributes.
Nutrient Contents of Raw and Cooked Cowpea Leaves
Authors: IMUNGI JASPER K. , POTTER NORMAN N.
Published: August 2006

SEEDS OF COWPEA (Vigna unguicullata) cultivar MM4 obtained from Kenya were grown for their leaves as a vegetable. The mean crude protein contents of the leaves from the 1981 and 1982 seasons were 32.8 and 34.3% of total solids, respectively, and leaves were a particularly good source of minerals, including iron, calcium, phosphorus and zinc. Levels of vitamin C, total carotene, and free and total folacin were 410 mg, 57 mg, 334 meg and 2012 meg, respectively, per 100g of solids. Freshly harvested leaves cooked by a traditional Kenyan technique retained 88% of their crude protein and substantial quantities of minerals. Losses in vitamin C and free and total folacin were 87%, 49% and 66% while their recoveries in the cooking water were 5.6%, 20% and 12%, respectively. Carotene in the cooked leaf solids increased slightly. Comparisons with other leafy vegetables indicate good potential for processing.
Biochemical Study on the Nonprotein Trypsin and Chymotrypsin Inhibitors in the Soybean
Authors: HAFEZ YOUSSEF S. , MOHAMED ALI I.
Published: August 2006

The chemical properties of nonprotein trypsin inhibitor (NPTI) and nonprotein chymotrypsin inhibitor (NPCTI) in the soybean were studied. NPTI was extracted with 50% methanol and treated with TCA to a final concentration of 16% (W/V). Two dimensional thin‐layer chromatography was used to make a peptide map of the methanol extract; 14 spots were observed. To distinguish the active peptides, the sample was mixed with trypsin or chymotrypsin; some peptides disappeared which formed complexes with the enzyme. The relative rate of inhibition indicated that inhibition was stoichiometric for trypsin and chymotrypsin. Dissociation constants of complexes (enzyme and inhibitor) showed that inhibition of chymotrypsin and trypsin were competitive and uncompetitive, respectively.
Calorimetric Studies on Whey Freeze Concentration
Authors: BAKSHI A. S. , JOHNSON R. M.
Published: August 2006

The freezing point of whey was determined at 3,5, 10,15, and 20% solids content in an automatic Osmometer, and effective molecular weight of the solute was determined to be 235 using freezing point depression equations. Differential Scanning Calorimetery was used to estimate the specific heat of whey in the temperature range ‐40 to 20°C. The frozen water fraction and refrigeration requirements are predicted as a function of temperature. Correlations of enthalpy and the freezing point of whey are presented. With these correlations, energy required for freezing whey can be computed. The application of therm odynamic data to whey freeze concentration is demonstrated.
Nutritional Effects of Fresh, Laboratory Heated, and Pressure Deep‐Fry Fats
Authors: ALEXANDER J. C. , CHANIN B. E. , MORAN E. T.
Published: August 2006

Cooking fats from a pressure deep‐fat frying operation producing fried chicken, were compared with laboratory heated and fresh fats in the diets of animals. Included were corn oil (CO), peanut oil (PO), and partially hydrogenated soybean oil (HSBO). Weanling rats were fed diets containing 15% fat for 28 days. Laboratory heating reduced absorption of CO and PO, but not that of HSBO. Pressure deep‐frying increased absorption of HSBO. Animals derived less metabolizable energy from diets containing heated or hydrogenated fats relative to fresh oil. Polar lipid fractions of liver changed due to heating. Pressure deep‐frying with fats resulted in less deterioration than with laboratory heating, as shown by chemical analyses, coefficient of digestibility, and metabolizable energy studies.
Kinetics of Chlorophyll Degradation to Pyropheophytin in Vegetables
Authors: SCHWARTZ S. J. , VON ELBE J. H.
Published: August 2006

Pyropheophytins a and b were determined as predominant chlorophyll derivatives in heat processed spinach. Chlorophylls a, b, pheophytins a, b and pyropheophytins a, b were quantitated in fresh, blanched and heat processed spinach at 116, 121 and 126°C. First order degradation rate constants were determined to calculate activation energies of 25.2 and 22.5 Kcal/mole for chlorophylls a and b and 20.7 and 15.7 Kcal/mole for pheophytins a and b, respectively. Based on the results, the suggested mechanism for the decomposition of chlorophyll during heat processing of vegetables is: Chlorophyll Pheophytin Pyropheophytin. Pyropheophytins a and b were major chlorophyll degradation products found in all commercially canned vegetable products surveyed.
Proteolytic Activity in the Sarcoplasmic Fluids of Parasitized Pacific Whiting (Merluccius productus) and Unparasitized True Cod (Gadus macrocephalus)
Authors: ERICKSON M. C. , GORDON D. T. , ANGLEMIER A. F.
Published: August 2006

Proteolytic enzymes in the sarcoplasmic fluid of Pacific whiting (Merluccius productus) were studied to determine which proteases might be involved in the severe textural defect associated with this species. The results were compared to those obtained for true cod (Gadus macrocephalus), a fish having firm texture. Two pH optima of enzymic activity were noted for whiting, pH 3.5–3.9 and 7.1–7.2. Two pH optima were also observed for cod, pH 3.2–3.6 and 7.8–8.0. Whiting but not true cod contained enzymic activity similar to cathepsin B. Cathepsin C activity was greater in whiting than in cod.
Heat Treatment and Drying of Capelin Mince. Effect on Water Binding and Soluble Protein
Authors: RUSTAD T. , NESSE N.
Published: August 2006

Capelin mince was heated and dried and the two functional properties, water holding and soluble protein, were measured as functions of time, temperature, moisture content in the mince, and rate of drying. Heating and drying reduced water holding and soluble protein. Loss of water holding started between 30 and 35°C while soluble protein was first reduced between 40 and 50°C. The effects increased with increasing time and temperature but were almost independent of moisture content in the range 30–70% water. Heat stability increased at low moisture contents. Water holding and soluble protein in dried samples were generally a little higher than in samples which were heat treated at corresponding times and temperatures.
Interference of Plant Polysaccharides and Tannin in the Coomassie Blue G250 Test for Protein
Authors: GODSHALL M.A.
Published: August 2006

Coomassie Blue G‐250, a quantitative color reagent used for protein analysis, reacts with tannin and polysaccharides found in cane juice and raw cane sugar. For this reason, the dye could not be used as a reagent for protein in these products. However, spectroscopic data showed that the complex formed with phenolic compounds possessed a different maximum than the protein complex. The spectrum of the complex between the dye and the nondialyzable fraction from raw sugar indicated the presence of phenolic moieties attached to this high‐molecular weight fraction. The reaction of several common plant polysaccharides and tannins with the dye could constitute a serious source of error in its use to determine protein in plant extracts.
Psychrotrophic Bacteria in Prerigor Ground Pork
Authors: JUDGE M. D. , COUSIN M. A.
Published: August 2006

The numbers of psychrotrophic bacteria in prerigor ground pork were slightly greater than in postrigor ground pork throughout an 11‐day storage period at 2°C. Freezing both types of samples and subsequent thawing before storage at 2°C reduced the initial psychrotrophic counts but the freezing effects did not persist beyond 8 days of storage. Differences in psychrotrophic counts between prerigor and postrigor ground pork were not sufficiently great in any comparison to limit the use of prerigor grinding of pork.
Moisture Losses During Chilling from the Skin Surface of Scalded Pork Carcasses
Authors: SCHAEFER‐ZEIDLER C. E. , JUDGE M. D. , ABERLE E. D.
Published: August 2006

The proportion of cooler shrinkage attributable to moisture loss from the skin of scalded, dehaired pork carcasses was estimated. Mean carcass cooler shrinkage was 1.91% during a 24 hr chill at —2°C. Approximately 80% of the cooler shrinkage was moisture endogenous to the skin. Thus, only 20% of total cooler shrinkage originated from the muscle and adipose tissue. Moisture was not absorbed in significant quantities by the skin during the scalding, dehairing and carcass washing process. Greater cooler shrinkage reported for scalded than for skinned pork carcasses was mostly a consequence of the widely different moisture content of the skin surface of scalded carcasses versus that of the adipose tissue surface of skinned carcasses.
Nucleic Acid, Purine and Proximate Analyses of Mechanically Separated Beef and Veal
Authors: SAVAIANO DENNIS A. , SALATI LISA M. , ROSAMOND WAYNE D. , SALINSKY JOEL , WILLIS B. WELLS
Published: August 2006

Deoxyribonucleic acid (DNA), ribonucleic acid (RNA), purine (adenine, guanine, hypoxanthine and xanthine) and proximate analyses of mechanically separated (MS) beef and veal were conducted to verify and evaluate changes in nucleic acid content which may result from mechanical separation. DNA and total nucleic acid levels were higher in both MS beef and veal whereas RNA levels were higher only in MS beef compared to hand deboned (HD) counterparts. Adenine, guanine and xanthine levels were higher in MS beef and veal, and hypoxanthine levels were lower compared to HD counterparts. Total purine content of MS beef did not differ from HD beef, whereas the purine content of MS veal was slightly higher than HD veal. It would appear that the addition of MS products to the diet would not significantly alter total purine consumption and hence should pose no risk to hyperuricemic individuals.
Storage Study of a Gas‐Packaged Bakery Product
Authors: SMITH J. P. , JACKSON E. D. , OORAIKUL B.
Published: August 2006

English style crumpets were packaged in the atmosphere of CO2 and N2 (3:2) and stored at 20°, 22°, 24° and 30°C. In all cases, package volume and headspace CO2 concentration decreased during the first week of storage. At 30°C, the volume started to increase after 12 days due to production of CO2 and other metabolites by microorganisms. At 24°C, the volume did not start to increase until after 25 days, while at 22° and 20°C it remained stable or gradually decreasing. Aerobic plate counts and metabolites were higher in the product stored at 30°C for 19 days than those stored at 20°C for 1 month. Product pH after 1 month at 20°C was lower (5.9) than that at 30°C for 19 days (6.5) due, essentially, to the absorption of CO2.
Antibacterial Activity of Selected Hydroxycinnamic Acids
Authors: HERALD P. J. , DAVIDSON P. M.
Published: August 2006

The objective of this study was to determine the antibacterial effectiveness of selected hydroxycinnamic acids (caffeic, ferulic, pcoumaric) against Escherichia coli and Staphylococcus aureus at pH 5.0, 6.0 and 7.0 and Bacillus cereus at pH 6.0, 6.5 and 7.0. p‐Coumaric acid was generally the most effective inhibitor tested causing <99.9% inhibition of E. coli at 1000 μg/ml (pH 5.0, 48 hr), S. aureus at 500 μg/ml (pH 5.0, 48 hr), and B. cereus at 500 μg/ml (pH 7.0, 9 hr). Inhibition increased as pH decreased with E. coli and S. aureus but not B. cereus. Bacillus cereus appeared to be the most susceptible strain with 1000 μg/ml of the compounds tested causing <99% inhibition at all three pH's.