Film-forming ability of fish proteins

Characteristics of films obtained from fish myofibrillar proteins extracted from various solubilization methods were investigated. In this study, we utilized three agents to solubilize fish myofibrillar proteins from surimi, which are sodium chloride, sodium tripolyphosphate, and alkaline condition. The first part of this study focused on combination of sodium chloride and alkaline solubilization, while the second part discussed combination of sodium chloride and sodium tripolyphosphate solubilization. Surimi concentration (15 and 20%), sodium chloride concentration (0, 2, and 5%), pH (7, 9, and 11), and STP concentration (1.0, 1.5, and 2.0%) were varied. Our findings suggested that film with high flexibility, indicated by high puncture distance and elongation at break, were obtained from surimi slurries with 20% surimi-0% salt-pH 11, 15 and 20% surimi-0% salt-1% STP, and also from 20% surimi-2% salt-pH 9 and 11. Films with high puncture strength were produced from treatments with 20% surimi-0% salt-pH 11, 15% surimi-2% salt-pH 9, and 15 and 20% surimi-0% salt-1% STP. Increased tensile strength was found mainly on films produced from slurries with 5% salt. We predicted that high tensile strength was associated with salt crystallinity. Therefore, we disregarded this property in selection of fat blocking solution. Considering puncture strength, puncture distance, and elongation at break data together, we considered surimi slurries with 20% surimi-0% salt-pH 11, 15% surimi-0% salt-1% STP, and 20% surimi-0% salt-1% STP should be appropriate for our further study

Bulk and Compound-Specific Stable Isotope Analysis for the Authentication of Walnuts (Juglans regia) Origins.

Walnuts are grown in various countries, and as product origin information is becoming more important to consumers, new techniques to differentiate walnut geographical authenticity are needed. We conducted bulk stable isotope analysis (BSIA) and compound-specific stable isotope analysis (CSIA) on walnuts grown in seven countries. The BSIA consisted of δ13Cbulk, δ15Nbulk, and δ34Sbulk, and CSIA covered δ2Hfatty acid, δ13Cfatty acid, δ13Camino acid, δ15Namino acid, and δ2Hamino acid. Analysis of variance (ANOVA) and linear discriminant analysis (LDA) were used for statistical analysis to compare samples from the USA and China. Parameters that yielded significant variations are δ2HC18:1n-9, δ13CC18:2n-6, δ13CC18:3n-3, δ13CGly, δ13CLeu, δ13CVal, δ2HGlu, δ2HIle, δ2HLeu, and δ2HThr. Our findings suggested that CSIA of fatty acids and amino acids can be useful to differentiate the geographical provenance of walnuts

Impact of Gravity-Driven Membrane Filtration Water Treatment Systems on a Rural School in Indonesia

Improving access to safe drinking water in developing countries is still a challenge and Gravity-Driven Membrane (GDM) filtration systems may be a sustainable solution. Two rural schools in West Java Indonesia were studied, one as a control site and another having an installed GDM system. Chemical and microbiological water quality data were collected for an initial 3-month period at the GDM site and a final sampling at the study’s conclusion (6 months) at both sites. After the initial 3-month period, health surveys were conducted with students self-reporting incidences of diarrhea for 3 months at both school sites. An analysis of the chemical parameters indicated that both schools had good water quality. An average 2-log reduction of fecal indicator bacteria at the GDM site was observed, with the control site having numbers that exceeded the upper detection limits (>3.38 log CFU/100 mL). Student diarrhea incidence at the GDM site declined from 0.077 at the survey onset to 0.052 at the latter half of the survey period, while the control site had a diarrhea incidence of 0.077 throughout. The results indicate that GDM technology can serve as a practical water filtration technology, improving access to safe drinking water for rural populations

Impact of Gravity-Driven Membrane Filtration Water Treatment Systems on a Rural School in Indonesia

Improving access to safe drinking water in developing countries is still a challenge and Gravity-Driven Membrane (GDM) filtration systems may be a sustainable solution. Two rural schools in West Java Indonesia were studied, one as a control site and another having an installed GDM system. Chemical and microbiological water quality data were collected for an initial 3-month period at the GDM site and a final sampling at the study’s conclusion (6 months) at both sites. After the initial 3-month period, health surveys were conducted with students self-reporting incidences of diarrhea for 3 months at both school sites. An analysis of the chemical parameters indicated that both schools had good water quality. An average 2-log reduction of fecal indicator bacteria at the GDM site was observed, with the control site having numbers that exceeded the upper detection limits (>3.38 log CFU/100 mL). Student diarrhea incidence at the GDM site declined from 0.077 at the survey onset to 0.052 at the latter half of the survey period, while the control site had a diarrhea incidence of 0.077 throughout. The results indicate that GDM technology can serve as a practical water filtration technology, improving access to safe drinking water for rural populations