R. T. TOLEDO

University of Georgia

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John A. Carpenter

University of Pittsburgh

M. K. Hamdy

National Research Centre

Cindy M. Lee

Clemson University

P.J. Milly

University of Georgia

D. A. Lillard

University of Georgia

R. R. EITENMILLER

University of Georgia

Jie Deng

Second Affiliated Hospital of Xi'an Jiaotong University

Harmeet S. Guraya

Agricultural Research Service

William L. Kerr

University of Georgia

Sui‐Yuan Chang

National Taiwan University

Cooperative Institutions

University of Georgia

Agricultural Research Service

United States Department of Agriculture

North Carolina State University

United States Food and Drug Administration

University of California, Davis

Iowa State University

Georgia College & State University

Arkansas Agricultural Experiment Station

Rutgers, The State University of New Jersey

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DEGRADATION OF FISH MUSCLE DURING MECHANICAL DEBONING AND STORAGE WITH EMPHASIS ON LIPID OXIDATION

Journal of Food Science (1977)

Cindy M. Lee R. T. TOLEDO

ABSTRACT Deterioration of mechanically separated fish flesh as measured by extent of lipid oxidation and color change was studied using fresh mullet (Mugil spp.). The parameters studied included contact with iron surfaces, mechanical stress applied to the muscle during deboning, temperature of deboning drum, washing of deboned fish flesh, and postdeboning treatments including addition of antibiotic, sparging with nitrogen gas, cooking, freezing and thawing. TBA value was used as an index of lipid oxidation and the reflectance ratio of metmyoglobin to oxymyoglobin as an index of color change was determined using reflectance spectrophotometry. The degree of stress applied during deboning did not cause any significant variations in TBA value, whereas increased temperature of the deboning drum showed an adverse effect which became significant with prolonged storage. Contact of flesh with iron parts of the deboner resulted in a pronounced increase in TBA value of the flesh within the short span of time involved in the deboning process. Washing improved significantly product quality when the product was frozen for an extended period, but appeared to have no major advantage when stored under refrigeration and immediately processed. A marked rise in TBA value occurred during thawing with the effect being more pronounced with increased thawing time. The effect of thawing also became more pronounced with extended frozen storage. Ambient oxygen and microbial activity appear to have an insignificant role in lipid oxidation during storage. The lateral tissue (red muscle), tissue along the visceral cavity, and bone marrow exudate appeared to be the most susceptible to the development of oxidative rancidity. Rate of TBA value change was very rapid when these muscles had contact with iron surfaces.

Flesh

Lipid Oxidation

Metmyoglobin

10.1111/j.1365-2621.1977.tb08447.x

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Citations (34)

Effect of Heat Treatment for Trypsin Inhibitor Inactivation on Physical and Functional Properties of Peanut Protein

Journal of Food Science (1982)

D.J. Perkins R. T. TOLEDO

ABSTRACT Trypsin inhibitor (TI) inactivation in whole peanut kernels exposed to moist heat had a decimal reduction time (D) of 91 min at 100°C and 9.3 min at 120°C. When all processing times were converted to process time at 120°C using Z of 20°C, the composite D at 120°C was 10 min. Solubility decreased with heating to reach a minimum with 98% TI inactivation. Capacities to spontaneously absorb water and to gel were retained better on heating at 120°C than at 100°C for equal TI inactivation. The most functional protein was in kernels heated at 120°C for 10 min. When 20 or 30% meat protein in a meat loaf formulation was replaced with the latter peanut protein, the resulting loaf retained more fat and water and exhibited higher shearing strengths than all meat formulations.

Trypsin inhibitor

10.1111/j.1365-2621.1982.tb12745.x

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Citations (17)

Descriptors for Texture Profile Analysis of Frankfurter‐Type Products from Minced Fish

Journal of Food Science (1982)

P. M. AROCHA R. T. TOLEDO

ABSTRACT The texture profile of frankfurter‐type products prepared from minced Spanish mackerel ( Scomberomorus maculatus ) was evaluated. Twelve character notes were identified: springiness, hardness, cohesiveness, moisture release, crumbliness, coarseness, graininess, juiciness, adhesiveness, lumpiness, chewiness, and mouthfeel‐oiliness. Overall texture acceptability was also evaluated. Differences in juiciness and mouthfeel‐oiliness were not detected. Springiness, hardness, cohesiveness, and lumpiness had the highest correlation with the overall texture acceptability. Products with 10% soy protein fiber (SPF) were better accepted than those having 20% or no SPF. Egg white (to 20%) improved the texture; however, its flavor was detectable when 10% or more was added. The most acceptable texture was exhibited by products containing 5–10% ground drumdried fish.

Chewiness

Mouthfeel

Texture (cosmology)

10.1111/j.1365-2621.1982.tb12693.x

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Citations (11)

Heat Transfer and Simulated Sterilization of Particulate Solids in a Continuously Flowing System

Journal of Food Science (1989)

Shih‐Ying Chang R. T. TOLEDO

ABSTRACT The heat transfer coefficients (h) between a cube and water were 239 and 303 W/m 2 K at 0 and 0.86 cm/s relative velocity. In 35% sucrose and 0 cm/sec, h was 146 W/m 2 K. A model for heat lethality in cubes during continuous sterilization which used finite difference equations for heat conduction and above values of h, revealed that hold times for 6D inactivation of PA 3679 (F 0 = 7.2 min) in an isothermal fluid at 132.2°C were 1.78 and 5.2 min for 1 and 2 cm cubes when h was 303 W/m 2 K and 1.23 and 4.13 min when h was 2500 or higher. When h was 239 W/m 2 K, hold times were 2.36 and 6.02 min for 1 and 2 cm cubes. When fluid entered the hold tube at 132.2°C and particle to fluid ratio was 0.56, fluid‐particle heat exchange increased hold time to 12.2 and 119 min for 1 and 2 cm cubes.

Isothermal process

Sterilization

10.1111/j.1365-2621.1989.tb07935.x

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Citations (63)

Vacuum or Modified Atmosphere Packaging and EDTA-Nisin Treatment to Increase Poultry Product Shelf Life

The Journal of Applied Poultry Research (1999)

D.E. Cosby Mark A. Harrison R. T. TOLEDO S.E. Craven

These experiments sought to increase the shelf life of poultry by treatment with a disodium ethylenediametetra-acetate (EDTA) and nisin (NIS) combination and storage under modified atmosphere packaging (MAP) or vacuum packaging (VP). Chicken drummettes were soaked with various combinations of EDTA and NIS for 30 min at 15°C and stored at 4°C. Parts treated with EDTA-NIS stored under VP had significantly lower (P≤.01) total aerobic plate counts than untreated controls stored under aerobic conditions. EDTA-NIS increased shelf life by a minimum of 4 days when packaged in aerobic conditions and a maximum of 9 days when vacuum packed. A second experiment evaluated the VP and EDTA-NIS combinations in more detail. Parts treated with EDTA-NIS stored under VP had significantly different (P≤.01) aerobic counts from parts treated with EDTA-NIS stored under aerobic conditions or untreated control parts. EDTA-NIS treatment increased shelf life 4 to 7 days in the second experiment. The results indicate that a combination of EDTA-NIS treatment and vacuum packaging has the potential to significantly increase the shelf life of raw processed poultry.

Modified atmosphere

Vacuum packing

10.1093/japr/8.2.185

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Citations (34)

FILTRATE FLOW THROUGH FILTER CAKES WHICH EXHIBIT TIME DEPENDENT RESISTANCE

Journal of Food Processing and Preservation (1989)

Sui‐Yuan Chang R. T. TOLEDO H. S. LILLARD

Filtrate flow through filter cakes which exhibits time dependent resistance was studied by measuring filtration rates through four types of perlite filter aids using a laboratory test system. Poultry chiller overflow water which has the potential for significant savings if recycled was used as the test suspension. Assumption of constant specific cake resistance and determination of its value from a plot of filtration rate against cummulative filtrate volume resulted in negative values for the medium resistance and large deviation between predicted and experimental values of filtrate volume particularly in the early stages of the filtration cycle. Equations were derived for independent determination of filtration medium resistance, which enabled determination of time dependent cake resistance factor. An equation which considered a time dependent cake resistance predicted values for filtrate volume which agreed well with experimental data. Data show that batch filtration of chiller overflow water will require very short cycle times for optimum filtrate flow.

Filtration (mathematics)

Flow resistance

Specific resistance

Perlite

10.1111/j.1745-4549.1989.tb00085.x

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Citations (3)

Heat transfer during thermal processing of a temperature dependent non-Newtonian fluid in a tubular heat exchanger

Chemical Engineering and Processing - Process Intensification (2006)

Cynthia Ditchfield Carmen C. Tadini Rakesh K. Singh R. T. TOLEDO

NTU method

Volumetric heat capacity

10.1016/j.cep.2006.05.018

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Citations (5)

Inactivation of Food Spoilage Microorganisms by Hydrodynamic Cavitation to Achieve Pasteurization and Sterilization of Fluid Foods

Journal of Food Science (2007)

P.J. Milly R. T. TOLEDO Mark A. Harrison D. Armstead

Hydrodynamic cavitation is the formation of gas bubbles in a fluid due to pressure fluctuations induced by mechanical means. Various high-acid (pH < [corrected]/= 4.6) fluid foods were processed in a hydrodynamic cavitation reactor to determine if commercial sterility can be achieved at reduced processing temperatures. Sporicidal properties of the process were also tested on a low-acid (pH > [corrected] 4.6) fluid food. Fluid foods were pumped under pressure into a hydrodynamic cavitation reactor and subjected to 2 rotor speeds and flow rates to achieve 2 designated exit temperatures. Thermal inactivation kinetics were used to determine heat-induced lethality for all organisms. Calcium-fortified apple juice processed at 3000 and 3600 rpm rotor speeds on the reactor went through a transient temperature change from 20 to 65.6 or 76.7 degrees C and the total process lethality exceeded 5-log reduction of Lactobacillus plantarum and Lactobacillus sakei cells, and Zygosaccharomyces bailii cells and ascospores. Tomato juice inoculated with Bacillus coagulans spores and processed at 3000 and 3600 rpm rotor speeds endured a transient temperature from 37.8 to 93.3 or 104.4 degrees C with viable CFU reductions of 0.88 and 3.10 log cycles, respectively. Skim milk inoculated with Clostridium sporogenes putrefactive anaerobe 3679 spores and processed at 3000 or 3600 rpm rotor speeds endured a transient temperature from 48.9 to 104.4 or 115.6 degrees C with CFU reductions of 0.69 and 2.84 log cycles, respectively. Utilizing hydrodynamic cavitation to obtain minimally processed pasteurized low-acid and commercially sterilized high-acid fluid foods is possible with appropriate process considerations for different products.

Clostridium sporogenes

Pasteurization

Sterilization

Bacillus coagulans

10.1111/j.1750-3841.2007.00543.x

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Citations (90)

Protein‐Protein Interaction and Fat and Water Binding in Comminuted Flesh Products

Journal of Food Science (1981)

Janice Ng R. T. TOLEDO D. A. Lillard

ABSTRACT The possible role of protein‐protein interaction in influencing the water and fat binding capacity of comminuted flesh products was studied. Water and fat binding by meat batters diminish when temperatures exceed 16°C during comminution. The loss of binding capacity was partially reversible, and cooling the batters to 0°C by addition of dry ice and rechopping allowed a partial recovery of the fat and water binding capacity. A cause and effect relationship between the change in fat and water binding by meat batters on chopping and protein‐protein interaction in actomyosin solutions was demonstrated. Protein‐protein interaction results in molecular aggregation and when measured as an increase in light scattering absorbance at 320 nm by a protein solution, the reaction was shown to be reversible between 4 and 30°C. When actomyosin solutions extracted from meat samples showed reduced protein‐protein interaction in the temperature range used in chopping, the batters made from these meats also showed the least loss in fat and water binding capacity with prolonged chopping. Controlling temperatures during chopping within a range where protein‐protein interaction in actomyosin solutions was found to be minimal, allowed prolonged chopping without loss in fat and water binding.

Flesh

Water-Holding Capacity

Absorbance

10.1111/j.1365-2621.1981.tb03004.x

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Citations (21)

EFFECT OF SMOKEHOUSE TEMPERATURE, HUMIDITY AND AIR VELOCITY ON RATE OF HEATING AND QUALITY OF FRANKFURTERS

Journal of Food Science (1974)

C. W. MONAGLE R. T. TOLEDO R. L. Saffle

The effects of air velocity, relative humidity, temperature and presence of glucono delta lactone (GDL) on the quality of frankfurters, were evaluated. Rate of heating was inversely proportional to rate of weight loss during processing. High humidity processes at slow air flows had the fastest heating rates; however, quality was unacceptable because of fat separation and pale color. A process where the smokehouse temperature was slowly increased by 6°C increments, and where a low relative humidity and high air flow were used, gave the best quality. Color and texture was more desirable on products having higher shrink. The presence of GDL had no effect on the final color of products processed under the same conditions; however, maximum color appeared to develop earlier in samples containing GDL.

Air velocity

10.1111/j.1365-2621.1974.tb02958.x

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Citations (20)