องค์ประกอบทางเคมี โครงสร้าง และคุณสมบัติของกล้ามเนื้อที่มีผลต่อลักษณะเนื้อสัมผัสของเนื้อไก่พื้นเมืองไทยและไก่กระทง

Thesis (Ph.D., Food Technology)--Prince of Songkla University, 200

Imaging Analysis by Digital Camera for Separating Broiler Breast Meat with Low Water-Holding Capacity

Separating breast meat with low water-holding capacity, conformation parameters (thickness, volume, bottom sarea, and perimeter), and color of chicken breast meat were measured by direct measurement and by imaging analysis with a digital camera. Samples were obtained from a production line. The L* value was used to separate the samples by three characteristics designating the quality of the meat: dark-colored samples (L*<50), normal-colored samples (50≤L*≤56), and light-colored samples (L*>56). Light-colored samples had higher moisture content, thawing loss, drip loss, and lower pH compared with those of normal- and dark-colored samples. Lower thickness was observed in the light-colored samples compared with those of normal- and dark-colored samples. Light- and normal-colored samples had a greater volume of meat than did the dark-colored samples. Imaging analysis showed that light-colored samples had a greater bottom area and perimeter compared with those of normal- and dark-colored samples. However, these conformation parameters showed low correlation with water-holding capacity, which was determined as thawing and drip loss of the samples. Therefore, the conformation parameters, determined by direct measurement or imaging analysis, could not be used to predict the water-holding capacity of breast meat. Nevertheless, water-holding capacity showed high correlation with the L* value of breast meat. Imaging analysis could be used to separate light-colored breast meat with mostly low water-holding capacity. The accuracy of determining the characteristics of light-, normal-, and dark-colored samples by imaging analysis was evaluated. The characteristics of light-colored samples were determined with higher accuracy by imaging analysis than were the characteristics of normal- and dark-colored samples. This result indicated that imaging analysis using a digital camera could be used to separate light-colored breast meat with mostly low water-holding capacity from normal- and dark-colored meat

Quality characteristics of raw and canned goat meat in water, brine, oil and Thai curry during storage

The quality characteristics of three groups of goat meat obtained from one year and three years old Anglonubian crossed native, and culled Saanen crossed native were investigated. Significant differences in fat, ash and total collagen content, were observed among groups of goat meat (P0.05) during storage. The influence of groups of goat meat on TBARS value was significantly observed (P<0.05) when processed in water and brine. Massaman curry could reduce the change in TBARS value of canned goat meat during storage. The results based on texture, color and lipid oxidation suggested that there were no significant differences between the groups of goat meat from 3 years Anglonubian crossed native and 7 years Saanen crossed native for being processed in canned goat meat curry products

Suitability of sago starch as a base for dual-modification

The quality and physicochemical properties of native sago starch were studied in order to evaluate the suitability of sago starch as a base for dual-modification, hydroxypropylation and crosslinking. The properties of starch derivatives obtained from dual-modification are different depending upon the kind of starch bases used and their basic properties. Therefore, the properties of several starches including waxy maize, waxy barley, tapioca, wheat, corn and rice and properties of their derivatives were investigated comparatively. The data obtained elucidates that the swelling power of a starch base is the most important factor which influences the dual-modification. The native sago starch had higher swelling power and bigger average granule size when compared to that of other starch bases. Its gelatinization temperature was in the same range as that of waxy maize while its pasting characteristic was similar to that of tapioca starch. It can be inferred that sago starch is suitable as a starch base for hydroxypropylation and crosslinking

Characterisation of hydroxypropylated crosslinked sago starch as compared to commercial modified starches

The characteristics of hydroxypropylated crosslinked sago starch (HPST) were determined and compared with five types of commercial modified starches (CMST) in order to evaluate its quality for further applications. The HPST was prepared on a large scale having molar substitution (MS) and degree substitution (DS) values in the range of 0.038 to 0.045 and 0.004 to 0.005, respectively. The properties of HPST in terms of sediment volume, swelling power, solubility and paste clarity were 15.75%, 16.7, 8.62% and 5.18%T650 , respectively. The MS value, phosphorus content, paste clarity, swelling power and syneresis after six freeze-thaw cycles of HPST when compared to that of commercially available modified starches which are normally used or incorporated in acidic, frozen and canned foods did not differ significantly. The pasting characteristic of HPST exhibited thin to thick viscosity which was similar (P>0.05) to that of commercial hydroxypropylated crosslinked tapioca starch (NAT 8). The acid stability, solubility and freeze-thaw stability of both starches were also similar (P>0.05) but the swelling power of HPST was slightly lower (P<0.05) than that of NAT 8

Changes in the Quality of Chicken Breast Meat due to Superchilling and Temperature Fluctuations during Storage

The aim of this study was to determine the changes in chicken breast meat quality (water-holding capacity, color, texture, myofibrillar fragmentation index (MFI), total protein solubility, thiobarbituric acid reactive substances (TBARS), total viable count (TVC), and lactic acid bacteria (LAB) count) due to storage under superchilling conditions (−1.3°C) and fluctuating temperatures (ranging from −20°C to −5°C) as compared to the quality of meat stored at chilled (2–4°C) and frozen (−20°C) temperatures, respectively. Results indicated that the TVC and LAB count of the chilled and superchilled breast meat increased with storage time. TVC of the chilled and superchilled breast meat reached the safety level of 7 log cfu/g at approximately day 8 and18, respectively. This suggested that the superchilling method extended the storage duration by 10 days. Weight loss and TBARS of the chilled and superchilled samples tended to increase with increasing storage time. The color, texture, protein solubility, and MFI were stable throughout the entire storage period of the chilled (9 days) and superchilled (28 days) samples. Results indicated that while three cycles of storage temperature fluctuation influenced the weight loss and dry matter of the meat, they did not affect the TVC, LAB count, texture, color, pH, MFI, and protein solubility. The superchilling technique (−1.3°C) could extend the shelf-life of meat and maintain the quality of chicken breast meat. Fluctuations in temperature during frozen storage decreased the water-holding capacity of chicken breast meat, indicating that temperature stability should be maintained during frozen storage