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Item Improving shelf life of commercial borate-glycol based wood preservatives(4th International Research Symposium on Pure and Applied Sciences, Faculty of Science, University of Kelaniya, Sri Lanka, 2019) Nandasiri, H. I. S. I.; De Silva, R. C. L.Borates as wood preservatives have played an ever increasing role in preservation of wood against wood destroying insects and made them particularly attractive in today’s environmentally conscious market. But the precipitation of borates on storage in borate-glycol wood preservatives has largely limited their demand in the current wood preservative market. The main objective of this study was focused on the possibility of reducing the borate precipitation in order to expand the shelf life of these wood preservatives. A number of strategies were employed to lessen the precipitation of borates such as changing the solvent, boron concentration and boric acid to borax ratio. Different wood preservative formulations were prepared using monoethylene glycol (MEG) and monopropylene glycol (MPG) with varying boron percentages (10% -20%) and boric acid to borax ratio. Boron percentage in each formulation was determined by the titration method over six weeks and FT-IR-ATR analyses were carried out to confirm the composition of precipitate formed. Effectiveness of each formulation was measured by chemical retention, chemical penetration and laboratory no-choice feeding test using dry-wood termites. Mortality rate and wood weight loss of the test blocks were observed in termite no-choice feeding test. Wood preservatives made by MPG showed an earlier precipitation than MEG and wood preservatives having 20% boron precipitated earlier than that of the ones having 15% and 10% boron. This indicates that both type of solvent and boron concentration have a direct influence for the precipitation of borates in wood preservative. There was a remarkable difference between penetration and retention of wood preservatives made by different solvents and boron concentration. Highest penetration and retention were observed in the formulation containing 20% B in MPG. According to the termite no-choice feeding test, all the formulations showed 100% mortality when applied them in 1:1 (by volume) aqueous dilution of borate/glycol. Termite mortality increased from about 83% to 100% with increasing boron percentage 15% to 20% when applied 1:2 aqueous dilution of borate/glycol. According to the results obtained, 15% B in MEG with 1:1.50 boric acid to borax ratio is the suitable formulation for borate-glycol wood preservative owing to its high effectiveness to wood destroying insects, long shelf life and cost effectivenessItem Effect of pretreatments on extending the shelf life of minimally processed “Ela Batu” (Solanum surattense)(Tropical Agricultural Research and Extension, 2007) Dharmabandu, P.T.S.; de Silva, D.S.M.; Wimalasena, S.; Wijesinghe, W.A.J.P.; Sarananda, S.Due to the cumbersome nature of the cleaning process and high time consumption for the preparation, most Sri Lankan housewives are reluctant to prepare Solunum surattense (Sinh. Elabatu) as a vegetable for their diet. If S. surattense is available in „ready to cook‟ form it would become a popular vegetable among Sri Lankan housewives. Studies were carried out to identify the best conditions for minimal processing of S. surattense. As pre-treatments 2% (w/v) calcium chloride solution, 0.6% (w/v) turmeric solution, 1% (w/v) vinegar solution, 2% (w/v) calcium chloride + 0.6% (w/v) turmeric solution and 2% (w/v) calcium chloride +1% (w/v) vinegar solution were used. Low density polyethylene (LDPE) pouches (gauge 150) were used to pack pre-treated samples and stored them at 8ºC. In all the pre-treated samples stored at 8ºC, Salmonella and E. coli were absent and coliform counts were at acceptable levels. Sensory evaluation of cooked pre-treated samples showed that the sample pre-treated with 2% (w/v) calcium chloride was the best. In addition to shelf life, colour, and degree of browning of the treatments were also acceptable. Treating S. surattense cut fruits with 2% (w/v) calcium chlo-ride solution before packing in LDPE pouches and storing in 8ºC found to be the best method for extending shelf-life of the fruit. The product could be kept for seven days.