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Effects of different setting temperatures (40–70 °C) on properties of goat meat gels after heating at 90 °C were investigated. Setting at 60 °C with subsequent heating at 90 °C yielded the gel with the highest breaking force along with coincidentally lowest expressible moisture content (p < 0.05). The highest TCA-soluble peptide content was found in gel set at 70 °C (p < 0.05). Slight decrease in myosin heavy chain band intensity was noticeable when setting temperature increased. As setting temperatures increased, a∗ and b∗- values of gels generally increased, while L∗- values decreased (p < 0.05). Gel set at 60 °C had highest hardness, gumminess and chewiness (p < 0.05). Gel set at 60 °C had the most compact network with immense connectivity of protein strands. Gels set at 40–60 °C had higher texture and overall likeness scores, compared to the control (p < 0.05). Prior setting at 60 °C was recommended for making the good quality goat meat gel. [ABSTRACT FROM AUTHOR]

Biochemical characteristics of Cu,Zn-SOD derived from hen egg white and egg yolk were determined, and compared with those of enzymes from erythrocytes of hens and SOD standard. The presence of dimer with a molecular weight of 33.38 ± 0.34 kDa, and pI of 6.30 ± 0.15 was confirmed in samples of SOD extracted from egg yolk. Cu,Zn-SOD isolated from egg yolk had an optimum at pH 6. Average SOD activity in egg yolk was 98.5 ± 19.5 U·g −1 while in egg white reached 6.1 ± 0.8 U·g −1 . Changes in SOD activity of the egg yolk during its storage for 200 days were also described. FTIR analysis confirmed that the enzymatic protein described in this study was SOD, while MALDI-TOF analysis confirmed only SOD from erythrocytes. Since eggs are a cheap and easily obtainable source of SOD, this enzymatic protein could be used in food, cosmetic or pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Abstract: The presence of a protease in Artocarpus integer leaves, which are traditionally used as a meat tenderiser, was verified by the presence of a band at 69kDa, using caseinolytic zymography. Purification by temperature phase partitioning with Triton X-114, ammonium sulphate precipitation and gel filtration chromatography yielded a preparation with a 12-fold increase in enzyme purity and a final specific activity of 76.67U/mg. The cysteinic nature of this enzyme was confirmed through inhibition of enzyme activity by E-64 and iodoacetamide and enhancement of activity by cysteine and 2-mercaptoethanol. The protease retained 70% of its activity over a broad pH range (pH 6–12), with optimal activity recorded at pH 10 and 40°C. The enzyme was stable at temperatures up to 70°C, with 80% of its activity intact. Addition of 5mM Ca2+ stimulated enzyme activity and a kinetic study of the enzyme yielded K m and V max values of 0.304mg/mL and 0.735mg/mL/min, respectively. [Copyright &y& Elsevier]

Abstract: Acid soluble collagen (ASC) and pepsin soluble collagen (PSC) were extracted from scale of spotted golden goatfish (Parupeneus heptacanthus) with the yields of 0.46% and 1.20% (based on dry weight basis), respectively. Both ASC and PSC were characterised as type I collagen, containing α1 and α2 chains. β and γ components were also found in both collagens. Based on FTIR spectra, the limited digestion by pepsin did not disrupt the triple helical structure of collagen. ASC and PSC contained glycine (336–340 residues/1000 residues) as the major amino acid and had imino acids of 186–189 residues/1000 residues. Maximal transition temperatures (T max) were 41.58 and 41.01°C for ASC and PSC, respectively. From zeta potential analysis, net charge of zero was found at pH 4.96 and 5.39 for ASC and PSC, respectively. Both collagens exhibited high solubility in acidic pH (2–4) and were soluble in the presence of NaCl at concentration up to 20 and 30g/l for ASC and PSC, respectively. [Copyright &y& Elsevier]

Abstract: Type I collagen from the skin of ornate threadfin bream (Nemipterus hexodon) was purified and characterised. Purified type I collagen contained [α1(I)]2α2(I) as the dominant component with the co-presence of α1(I)α2(I)α3(I). It was rich in glycine and alanine with high content of imino acids (188 residues/1000 residues). The maximum transition temperature (T m) and the total denaturation enthalpy (ΔH) of purified type I collagen was 33.35°C and 0.819J/g, respectively. The isoelectric point (pI) of purified type I collagen was estimated to be 6.40. After hydrolysis of purified type I collagen using pepsin, the band intensity ratios of α1/α2-chains were increased (P <0.05). The cross-linked components were effectively hydrolysed by pepsin 1 and 2 from skipjack tuna stomach and porcine pepsin at 4°C without the cleavage of β- and α-chains. At 50°C, they were more susceptible to porcine pepsin hydrolysis, followed by pepsin 2 and 1, respectively. [ABSTRACT FROM AUTHOR]