Project Number: WVA00405
CRIS Number: 0180504
DEGREE OF MYOFIBRILLAR PROTEIN HYDRATION AND RAW MATERIAL FUNCTIONALITY IN PROCESSED MUSCLE FOODS
Investigators: Kenney, P. B.
Performing Department: Animal & Veterinary Science -- 1877
Start Date: 10/01/1998
Termination Date: 09/30/2003
Reporting period: 01/01/2001 to 12/31/2001
Progress Report:
Functional differences between beef and trout as extremes reveal that ingredient and environmental factors during processing should be carefully modified as a function of raw material characteristics. The objective was to determine the relationship between degree of myofibrillar hydration and protein functionality in further processed muscle of 3 species: trout, beef and chicken. Peeled beef knuckles, chicken breast, boneless trout fillets, and beef fat trim (80:20) were collected, ground, and formulated to contain 10% fat, 30% added water, 2% NaCl, 550-ppm sodium erythorbate, 120 ppm NaNO2, 0 or 0.4% STPP, and preblended with the NaCl for 0 or 12 h. The experimental design was a 3 x 2 x 2 factorial, randomized complete block design with 3 replications. Raw batter was used to measure pH, total protein solubility (TPS), soluble myosin, total myosin, hydrophobicity, and free SH. Cooked gels were used to measure pH, cook yield (CY), hardness and cohesiveness, and proximate composition. STPP did not affect raw pH, free sulfhydryl content, CY, gel hardness and cohesiveness in trout (P > 0.05). STPP increased raw pH, CY and gel hardness in beef and chicken (P < 0.05). STPP decreased free sulfhydryl content for beef and chicken. Surface hydrophobicity was highest in trout followed by chicken then beef (P < 0.05). STPP did not affect surface hydrophobicity of either beef or chicken. Preblending did not affect protein solubility (P > 0.05). STPP increased protein solubility (4.37 vs. 5.50 mg/ml; P < 0.05). Beef gels were firmer than chicken and trout. Trout had more soluble myosin than beef and chicken and STPP increased myosin three-fold. Total myosin was not different between species. Ionic strength, pH, and muscle source contribute to protein behavior throughout formulation and processing. Peeled beef knuckle, boneless trout fillets, and beef fat trim were collected and ground. Two NaCl levels (2 and 4%), two STPP levels (0 and 0.4%), two species (beef and rainbow trout), and 3 holding times prior to thermal processing times were replicated 3 times as a balanced incomplete block design with treatments nested in specie. Trout batter protein solubility (PS) and raw and cooked pH were higher (P0.05). Time did not affect (P>0.05) PS of treatments without STPP; however, extending the holding time to 48 h reduced (P0.05) cook yield for trout minces; whereas both ingredients increased (P0.05) hardness of trout minces, but it increased (P0.05), and at 48 h, STPP increased (P
Publications:
Jittinandana, S., P. B. Kenney, S. Slider, and R. Kiser. 2001. Cryoprotection of rainbow trout, Oncorhynchus mykiss, fillets for smoked trout production. Institute of Food Technologists Annual Meeting and Food Expo. New Orleans, LA.
Jittinandana, S., P. B. Kenney, S. Slider, and R. Kiser. 2001. Effects of cryoprotectants on physicochemical attributes of intact rainbow trout, Oncorhynchus mykiss, fillets. Institute of Food Technologists Annual Meeting and Food Expo. New Orleans, LA.
Jittinandana, S. J. 2001. Effect of brine concentration and brining time on quality of smoked rainbow trout fillets. J. Food Sci. Accepted.
Mathias, J. S. 2001. Effect of vacuum tumbling with direct salting or brining on smoked trout fillets. MS Thesis Report, West Virginia University, Morgantown.
Impact:
Defining mechanisms that dictate myosin hydration in an environment unique to processed meat systems will form the basis for increasing efficiency of raw material use and thus profitability of muscle-food production. This work shows that time increases raw material functionality by allowing solubilization followed by some degree of insolubilization. These two changes increased muscle food functionality.