Studies on Physical and Biochemical Properties of Hot-boned Pork Loin Chops Injected with Different Brines

• Main Authors: Yi-Hsien Chen, 陳義弦
• Other Authors: Ying-Yu Tseng , Ph. D.
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/72940083974891898781

碩士 === 國立屏東科技大學 === 畜產系 === 92 === Abstract The purpose of this study was to investigate the influence of hot-boned pork loin injection with different brines, on the improvment of eating quality, and the changes on biochemical of pork chops. Hot-boned M. longissimus dorsi were purchased from local market, divided into four treatments, each treatment had 12 repeate loin was injected with 10% (w/w) of 5% sodium chloride solution (SC), 5% sodium lactate (SL), combined solution (combined 3.5% sodium chloride, 5% sodium lactate and 1% sodium tripolyphosphate, COM), and the deionized water (DW) injection was as control. Biochemical properties on glycogen, and R-value within 48hr, salt soluble protein (SSP), ATPase activity and myofibrillar fragmentation index (MFI) within 120hr were measured. Physical properties of loin chops were detected on purge, cooking loss, and shear forces during storage at 2℃for 5 days, pH value, color, thiobarbituric acid reactive substance (TBARS), volatile basic nitrogen (VBN) and total plate counts (TPC) were detected within 10 days, and cooked pork loin chops were also evaluated at the third day by panelist. The results showed that during the first 6, 24 and 48 hr after injection, the glycogen concentration and pH value of COM and SC chops were significantly higher than those of DW and SL chops (P<0.05). The rate of ATP hydrolysis was also decreased at the first 3 hr of COM chops, and the R-value was the lower than others, but at the 24 hr the R-value of brines injection treatment significantly higher than DW chops (P<0.05). During storage time, the chops injection with brines were significantly lower in SSP but higher in MFI than DW chops (P<0.05), after 72hr injected, the ATPase activity of SC and COM chops were higher than COM chops, but SL was lower than DW chops. The loin chops injected with SC and COM brines deceased significantly on purge, cooking loss and shear forces also significantly lower than DW and SL chops (P<0.05). The pH value of four treatments chops decreased with increasing storage time at the first 10 days, whereas the DW showed the lowest, and the COM injection was the highest (P<0.05). Chops injection with COM brine had the most effect for extended redness (a value) and oxidation stability, but lower lightness (L value) than DW, SC and SL chops. The VBN value of chops injected with brine were lower than DW injection within the first 10 days storage time (P<0.05), the chops injection with SL and COM brines had the lowest total plate counts. Sensory evaluation showed that the chops injection with COM brine, which juiciness, tenderness and freshness was the highest (P<0.05), and SC was second. Although chops injected with COM brine higher score in saltiness, but the acceptability was also the most (P<0.05). In conclusion, hot-boned pork loin with 5% brine 10% (w/w) injection, and the best brine for injection was the COM, the SC brine was the second. Both eating quality and storage stability of chops were significantly improvement during 2℃storage for up to 10 days.