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The purpose of our study was to evaluate the effect of photodynamic therapy (PDT), using erythrosine as a photosensitizing agent and a dental halogen curing unit as a light source, on Streptococcus mutans in a biofilm phase. The S. mutans biofilms were formed in a 24-well cell culture cluster. Test groups consisted of biofilms divided into four groups: group 1: no photosensitizer or light irradiation treatment (control group); group 2: photosensitizer treatment alone; group 3: light irradiation alone; group 4: photosensitizer treatment and light irradiation. After treatments, the numbers of colony-forming unit (CFU) were counted and samples were examined by confocal laser scanning fluorescence microscopy (CLSM). Only group 4 (combined treatment) resulted in significant increases in cell death, with rates of 75% and 55% after 8 h of incubation, and 74% and 42% at 12 h, for biofilms formed in brain–heart infusion (BHI) broth supplemented with 0% or 0.1% sucrose, respectively. Therefore, PDT of S. mutans biofilms using a combination of erythrosine and a dental halogen curing unit, both widely used in dental clinics, resulted in a significant increase in cell death. The PDT effects are decreased in biofilms that form in the presence of sucrose.

One‐hundred‐twenty crossbred pigs finished at 175–185 days of age were used to investigate the effects of live weights at slaughter on the meat quality, volatile flavor compounds, and sensory attributes of pork meat. Based on the live weights at slaughter, three weight groups (n = 36 per group) were classified as follows: light weight (LW: 100 kg), medium weight (MW: 110 kg), and heavy weight (HW: 120 kg). After slaughter, longissimus dorsi muscle samples were taken and used for the analyses of aforementioned parameters. The HW group had higher fat content and water holding capacity compared to the LW or MW group (p < 0.05). The HW group also showed higher levels for majority of unsaturated fatty acids and total polyunsaturated fatty acids than the LW group (p < 0.05). The slaughter weight significantly affected the amounts of 11 among the 47 flavor compounds identified. Significantly higher amounts of fatty acids oxidation‐derived flavor compounds (aldehydes) were found in the HW group than in the other groups. Noticeably, increasing slaughter weight was associated with higher sensorial scores for flavor, juiciness, and acceptance scores (p < 0.05). Based on the obtained results, 120 kg body weight is recommended as the market weight for this commercial breed without compromising the meat quality.

Low-fat sausages with or without 10% hydrated rice flour were made from duck, chicken and pork and their physical and sensory properties were compared. Results showed that moisture content did not differ significantly among the sausage batters. However, crude protein, crude fat and total ash content were significantly lower in the group with added rice flour compared with the no flour group. Crude protein and crude fat were the highest in pork sausages without rice flour (p<0.05). Adding 10% rice flour reduced total expressible fluid in all meat type sausages. Cooking loss was also decreased when 10% rice flour was used in making sausages from chicken and pork. However, no changes in cooking loss were found in duck meat by adding rice flour. Again, the highest cooking loss was in pork sausages without rice flour and lowest in chicken sausages with 10% rice flour. The pH of the meat from different animal species differs significantly, although no significant difference was found within meat types with or without rice flour. Lightness (L*) increased, while redness (a*) decreased with adding rice flour in all meat type sausages. Results showed that hardness was significantly reduced when 10% rice flour was added to pork, chicken and duck meat (p<0.05). This may be due to increased water retention of rice flour after cooking. Sensory evaluation indicated that the overall acceptability of pork and chicken sausages with or without rice flour was the same, but duck sausages without rice flour had the highest off-flavor score among the sausages. Addition of rice flour increased the overall acceptability of duck sausage to that of pork and chicken sausages.