Browsing by Author "Bittel, Ralph J."

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    The characterization and utilization of mechanically separated bovine spleen
    Bittel, Ralph J. (Virginia Polytechnic Institute and State University, 1979)
    Studies were conducted to provide information about bovine spleen and its potential uses in comminuted meat products. Scientific data may generate interest and lead to the better utilization of this valuable source of iron and protein in human nutrition. An effective, economical means of removing capsular and internal connective tissue from splenic pulp was found. Beef spleens were passed through a Beehive deboner with a desinewing head. The process yielded 79.1 percent mechanically separated spleen (MSS) containing 17.0 percent protein, 2.9 percent fat and 762 ppm iron. The effect of mechanical separation on protein quality was determined by protein efficiency ratio (PER). Rats fed MSS and whole spleen diets exhibited significantly greater weight gains than those fed casein. PER values for whole spleen (2.4) and MSS {2.3) were not significantly. different. The PER value of casein (2.5) was significantly higher than that of MSS but not whole spleen. Beef and pork frankfurters were produced with 0, 5, 10 and 15 percent of the meat block being MSS. Substitutions of MSS were made at the expense of the pork portion of the formula. There were no major differences in proximate composition among the treatments. No fatting or peelability problems were experienced. Vacuum packaged frankfurters were held at 2°C and evaluated at 2 week intervals for 6 weeks. Initial frankfurter color, as indicated by internal and external Hunter L values and total and nitroso-heme pigments, intensified linearly with increased MSS. Each product showed significant fading of the external surface and loss of total pigment concentration. Rate and degree of change increased with increased MSS. Internal color of all except the 15 percent product was stable. Significant losses in nitroso pigment occurred in the 5 and 15 percent products. A physical attributes panel noted intensified cured meat color and decreased resilience, binding and overall physical acceptability with increased MSS. Consumer panelists rated all products acceptable for flavor, texture and color. A bi-monthly laboratory taste panel evaluated all frankfurters, except those containing 15 percent MSS, acceptable in flavor, texture, color and overall acceptability during storage. Allo-Kramer shear values verified the trend toward softer frankfurters with increased MSS indicated by the sensory panels. Frankfurters with 5, 10 and 15 percent MSS had 2.2, 3.9 and 4.9 times more iron than the control, respectively. Level of MSS did not influence bacterial numbers in the emulsions or cooked frankfurters. During storage, mesophiles increased whereas psychrophiles and coliforms decreased. No signs of spoilage were observed after 6 weeks storage. Meat patties containing 0, 5 and 10 percent MSS yielded 69 percent after oven broiling. Taste panelists rated all patties acceptable for juiciness, flavor, mouth-feel and overall acceptability. Cooked patties with 5 and 10 percent MSS contained 2.6 and 3.8 times the iron of the all-beef control, respectively. MSS is a valuable source of protein capable of elevating the iron value of comminuted meat products while maintaining consumer acceptability.
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    Methods to detect and quantitate spleen added to ground beef
    Bittel, Ralph J. (Virginia Polytechnic Institute and State University, 1975)
    Experiments were conducted to explore the feasibility of employing the storage iron compounds, hemosiderin and ferritin, as indicators for the detection and quantitation of spleen added to ground beef. Weighed amounts of ground beef and a composite spleen homogenate were combined to yield products with 0, 2.5, 5 and 10 percent spleen. A graded series was prepared at each of three fat levels. A quantitative procedure based on the organ specificity and insolubility of hemosiderin was tested. The soluble iron forms were removed by saline extraction and centrifugation. Any iron remaining in the residue was assumed to be hemosiderin iron. The retained iron was extracted by acid hydrolysis and quantitated colorimetrically with ferrozine and by atomic absorption. The residues from unadulterated samples held less than 4 μg Fe/g original sample. Insoluble iron increased linearly (Slope = 4.83) as the level of spleen in the product increased. The fat content of the products had little effect on the quantitation of added spleen. A qualitative spot test based on the solubility and heat stability of ferritin was investigated. Protein pellets prepared from unadulterated samples maintained a white to grey-white color after Prussian blue iron staining. Pellets from spleen-added samples developed a blue color. The amount and intensity of blue increased as the amount of spleen in the product increased. A presumptive test was performed by applying Prussian blue directly to the raw products. The spleen-added products developed a blue color.