1. Within a large flock of turkey toms (2000 BUT9 conventionally reared and slaughtered), early muscle pH measurements were randomly done to distinguish two groups of birds presenting low (fast glycolysing, GR) or normal (normal glycolysing, GN) values. 2. Subsequently, ultimate pH values and meat quality parameters were also recorded. Meat quality parameters from GR or GN samples differ more or less indicating more or less severe PSE conditions. Proteins extracted from the samples at 20 min post mortem were similar while they differed greatly at 24 h post mortem. Moreover, among the GR birds, a subgroup of animals (called AB) presented SDS-PAGE profiles largely different from other GR or GN birds. 3. All the subsequent analysis developed on meat quality parameters as well as for protein extractabilities also differed between AB and other animals indicating that they must be considered differently in term of PSE syndrome development. 4. Western blots against Myosin Heavy Chain and actin at 24 h post mortem indicate that myofibrillar protein alterations are different in AB and GR or GN samples. 5. At 20 min post mortem, glycogen content was lowest in AB samples while the glycolytic potential was similar in all samples at the time of death. Measurements of PFK enzyme specific activity did not indicate a different regulation of post mortem glycolysis in AB samples. 6. Our results suggest that a unique pH measurement at 20 min post is insufficient to detect animals more prone to developing a severe PSE syndrome in turkeys. In consequence, it is suggested that a more precise evaluation of the kinetics of pH and temperature decrease has to be conducted to understand the aetiology of meat quality parameter alterations in poultry.

This study was aimed to develop an albumen pudding by application and optimization of gelatin and carrageenan as food additives using response surface methodology (RSM). Albumen pudding was produced from 55% (v/v) albumen concentration. Effect of concentrations of gelatin (2, 4 and 6% (w/v)) and carrageenan (0.3, 0.5 and 0.7% (w/v)) on pudding’s physical and sensorial properties was investigated. Results revealed that a concentration of food additives correlated with syneresis, springiness, hardness, firmness and overall liking scores (R2= 0.932, 0.821, 0.956, 0.854 and 0.864, respectively). The higher gelatin and carrageenan concentrations added, the lower syneresis, springiness, hardness, firmness and overall liking scores were observed. The overall liking score ranged from 5.9-6.7 (slightly-liked to moderately-liked) compare to 7.5 (moderately-liked) of the control sample. From RSM analysis, the suitable concentrations of gelatin and carrageenan were 1.5-5.6% (w/v) and 0.25-0.61% (w/v), respectively.

Protein alterations of turkey breast muscles (Pectoralis major) were investigated at 20 min and 24 h post mortem. Specific activities, quantities and kinetic parameters of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and aldolase A were also determined at 20 min post mortem. Based on the pH values at 20 min post mortem, two groups of samples were classified as rapid glycolysis group (RG; pH 20 min 5 5.80 6 0.07, n 5 20) and normal glycolysis group (NG; pH 20 min 5 6.21 6 0.01, n 5 20). RG had lower specific activities of GAPDH and aldolase A than NG while V m and K m values of both enzymes were not different between groups. RG showed lower high ionic strength (HIS) and pellet protein extractabilities at 20 min post mortem. It also had lower low ionic strength (LIS) and HIS protein extractabilities at 24 h post mortem. Besides pellet protein, muscular protein extractabilities at 24 h post mortem were higher than at 20 min post mortem. From SDS-PAGE of samples at 24 h post mortem, RG exhibited lower band intensities at 45 and 200 kDa, which were further identified as actin and myosin heavy chain (MHC), respectively. Western blots revealed that relative amounts of actin and MHC at 20 min post mortem were not different between groups. However, RG muscles had less relative amount of actin at 24 h post mortem. It also indicated that amounts of actin and MHC increased with regard to post mortem time.

The food process generates certain amounts of agricultural wastes and by-products. These materials are considerably non-valuable and normally sold for livestock feed. Coconut residue is one of the by-products obtained from coconut milk extraction. Thus, this study was aimed to valorise coconut residue powder (CRP) by partial substitution of wheat flour in deep fried donut and butter cookies and to investigate how different CRP substitution levels affect the physical and sensorial qualities of these bakery products. CRP was prepared by drying coconut residues at 55oC for 9 hrs, size reducing with a blender at 24,000 rpm for 40 s and sieving through a 35-mesh sifter. Protein, ash, fat and carbohydrate contents of coconut flour were 3.82, 0.72, 39.83 and 55.64% on dry basis, respectively. After the utilization of CRP by partial substitution wheat flour in deep fried donut (5%, 10% and 15%) and butter cookies (10%, 15% and 20%), it was found that CRP can substitute wheat flour in the donut and cookies productions by 10% and 15%, respectively. Donuts with higher substitution levels had lower specific volume but higher L*, a*, ∆E*-values, hardness and chewiness. For butter cookies, an increase in CRP substitution level led to higher hardness but it did not significantly affect the fracturability and the ∆E*-value. An increase in CRP substitution level also reduced the overall-liking score. The overall-liking scores of fried donuts with 10% CRP substitution level and butter cookies with 15% CRP substitution level were 6.43 (slightly like) and 7.00 (moderately like), respectively. This study showed the value-adding of agricultural waste such as coconut residue by its application in food production.