Relationship Between Marbling Scores Of Pork And Sensory Attributes And Processing Functionalities

Marbling related with sensory attributes is an important factor of sensory attributes and processing functionalities. At present, research on pork classification according to marbling distribution is not found in our country, but found in America, Canada and Japan. In these countries, the researches were grouped mainly in the effect of marbling on eating qualities and sensory evaluation. No report was found on the relation between marbling and sensory attributes and processing functionalities. In this study, sensory scores were conducted on marbling of 180 longissimus lumborum (LD) from pig. Sensory attributes and processing functionalities of marbling pork was studied to elucidate internal relation between marbling and sensory attributes and processing functionalities which provided technical support for improving quality of pork and meat products.Chapter 1:The sensory attributes of pig LD with marbling scores were investigated, and further to elucidate internal relation between marbling and pork sensory attributes. Sensory scores were conducted on marbling of cut surface of the loin eye muscle between 5th and 6th rib. Pig LD with similar color and different marbling were used. Meat color, intramuscular fat content, cooked meat shear force, collagen content, juiciness and flavor of 10 strips LD in every marbling grade were investigated. The marbling was divided into 3 grades, and the range of intramuscular fat content of every marbling grades:Grade 1 (IMF: <2%), Grade 2 (IMF:2%-4%) and Grade 3 (IMF:>4%). With marbling grades increased, L*-value,b*-value and the intramuscular fat content increased significantly (P<0.01), cooked meat shear force and collagen content decreased significantly (P<0.01). Significant difference were found in flavor and juiciness between grade 3 and grade 1, grade 2(P<0.05).Chapter 2:The relationship between marbling scores and gel properties of pig LD at different ionic strength (0.45M,0.60M NaCl) and cooling methods(0℃,10℃). Results showed that gel properties of pork with marbling grades at 0.60M NaCl were better than 0.45M NaCl (P<0.05). Significant difference were found in gel WHC (P<0.01) and gel strength (P<0.05) among marbling grades under 0.60M NaCl and the same cooling method. But. no significant difference was found in gel elasticity (P>0.05). Gel properties of grade 3 was best under 0.60M NaCl and 10℃cooling. In addition, marbling grades were correlated with gel WHC (P<0.05), and were significantly correlated with protein solubility (P<0.01) and gel strength (P<0.01).Chapter 3:The relationship between marbling scores and emulsion properties of LD salt-soluble protein at different ionic strength (0.10M,0.30M,0.60M NaCl). Results showed that emulsifying capacity, emulsifying stability, emulsion pH of pork with marbling grades at 0.30M NaCl were higher than 0.10M and 0.60M NaCl (P<0.05). Emulsifying capacity of grade 1 and grade 2 at 0.30M NaCl were best. No significant difference were found in emulsifying stability among marbling grades (P>0.05). There were significant effects between marbling grades and emulsifying capacity, emulsion pH (P<0.01). Emulsifying capacity, emulsifying stability, emulsion pH and protein solubility were significantly effected by ionic strength (P<0.01). Protein solubility was significantly effected by interaction effect between sensory scores and ionic strength (P<0.01).