Palm and Latex Technology and Value Addition Degree Programme ( PLT)

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    Antagonistic Effect of Some Native Trichoderma Isolates on Economically Important Foliar Pathogens of Rubber
    (Uva Wellassa University of Sri Lanka, 2015) Sandamali, P.K.N.N.
    Rubber foliar diseases play an important role in latex yield losses of rubber plantations in Sri Lanka. The frequent use of chemical fungicides to control causative pathogens leads to environmental pollution, hazardous to human and may lead to the development of new chemical resist pathogenic strains. Trichoderma species are the most widely studied bio control agent (BCAs) against many economically important plant pathogens. Hence, an attempt was made to investigate the antagonistic effect of some native Trichoderma strains on the plant pathogenic fungi; Colletotrichum spp., Corynespora cassiicola, Phytophthora spp. and Drechslera heveae. Foliar pathogens were isolated and identified based on the symptoms, cultural and reproductive characteristics. Five Trichoderma strains isolated from different rubber growing soils in Sri Lanka were tested in vitro for their antagonistic effects against the four foliar pathogens. The results obtained from dual culture tests showed that all the five Trichoderma isolates effectively checked the growth of the four foliar pathogens. The test antagonists grew faster than the pathogen limiting their growth. Trichoderma isolate A was the best antagonist against Drechslera heveae, Corynespora cassiicola and Colletotrichum spp. showing percentage inhibition of 75.63 %, 51.34 % and 74.46 % respectively. Isolate B showed the best inhibition rate (70.99 %) against Phytophthora spp. All antagonists showed their lowest inhibition rates against Drechslera heveae. In conclusion, all the tested Trichoderma isolates showed antagonistic effects against four foliar pathogens under investigation. Therefore, the fungal strains can be used for further greenhouse and field studies to confirm the feasibility of using for the management of rubber foliar pathogens. Key Words: Trichoderma spp., Drechslera heveae, Corynespora cassiicola, Colletotrichum spp., Phytophthora spp., Bio Control Agents
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    Assessing the Impact of Addition of Mica Filler to the Neoprene Glove Manufacturing Process
    (Uva Wellassa University of Sri Lanka, 2013) Weerasekara, R.A.K.S.
    The synthetic rubber based supported glove industry plays the major role in rubber industry. In terms of economic advantage, the chemical handling gloves are more dominant compared to others. The chemical resistant Neoprene gloves are high cost products. In the current study, I examined the Mica is a cost reduction filler as well as reinforcement of the product. The incorporation of 5phr of filler was significantly improved the properties of glove. The glove weight is a critical parameter in terms of quality of the glove. There are number of factors are affecting to the variation of glove weight. The viscosity of the compounded latex is most crucial in determining the glove weight. The P value = 0.00 at 95% and 99% confidence interval. The weight is increased at the high viscosity levels and vise versa. Key words: Neoprene latex, Mica filler, Viscosity, Cost reduction, Glove Weight
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    Assessment on the Incidence of Tapping Panel Dryness and Yield Parameters of Different Rubber (Hevea Brasiliensis) Clones
    (Uva Wellassa University of Sri Lanka, 2013) Deshapriya, H.A.U.
    Tapping Panel Dryness (TPD) is a common disorder which is a complex physiological syndrome that causes severe reduction in yield and but does not lead to death of trees. TPD is one of the major problems in rubber industry which reduces the productivity of rubber. Until now, exact reasons for TPD have not been found. Generally high yielding clones are often considered susceptible to this physiological disorder. This study was carried out to find out clonal susceptibility to TPD and to find out correlations among yield parameters, yield and bark consumption rate of healthy and TPD trees of different clones. Four popular clones in the rubber estate at Kuruwita substation of the Rubber Research Institute were selected for the study. The clones were RRIC 100, RRIC 121, RRISL 201, and RRISL 202. The experimental blocks were selected from each field based on the availability of clones and on stage of tapping of those clones. Survey was begun early in the morning at the time of tapping, observing each tree with latex harvesters. For the analysis of latex parameters, thirty trees were selected from each block selecting 10 trees per each category, healthy, partial dry and fully dry trees. There is a significant association (p<0.05) between the genotype and panel dryness. Incidence of panel dryness appears to be low in clone RRIC 121. Clone RRISL 201 and RRISL 202 have shown a high incidence of fully dry trees than other two clones. Nevertheless, partial dryness was lowest in RRISL 201 (8%). It was found that the influence of the tree type (healthy or partial dry) significantly correlated with flow rate, latex volume and individual tree yield (g/t/t). Those parameters are significantly higher in healthy trees than partial dry trees. Bark consumption and plugging index did not correlate with the tree type. However, bark consumption rate, plugging index, flow rate and latex volume were significantly different among clones. Key words- Healthy trees, Partial dry trees, Physiological Syndrome, tapping panel dryness (TPD), yield parameters
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    Bioethanol Production from Palmyrah Molasses Using Saccharomyces Spp.omyces Spp.
    (Uva Wellassa University of Sri Lanka, 2014) Sinnarasa, S.
    Molasses is the waste material obtained from the production of palmyrah sugar candy could be used for alcohol production through fermentation process there by it reduces the production cost of sugar candy. The aim of the study was to select the suitable yeast species and optimize the fermentation conditions to produce ethanol from molasses. The best yeast strain for fermentation was selected according to their alcohol tolerance and growth on molasses using cell density. Molasses was undergone for the chemical analysis (brix, total sugar, reducing sugar, pH, total acidity and alcohol) which was used as fermentation medium .Optimization of fermentation was carried out with different initial brix (5, 10, 20, 30, 40 °Brix), inoculum size (1, 2, 3, 4 ml), pH (4, 4.5, 5, 5.5, 6, 6.5) and temperature (30, 35, 45, 55 °C), Each treatments were conducted with triplicate under controlled environment. The absorbance 1.016 and 1.576 were obtained as highest cell density per ml for 8.5 % of alcohol and growth on molasses respectively, the selected best yeast strain was used for the fermentation study. The initial brix, pH, total sugar and reducing sugar of the raw molasses was 58.73. °Brix 4.5, 62.39 and 8.06 % respectively while the alcohol content was nil. Significantly Brix 10° and inoculum size of 3 ml were selected as optimum at 3rd and 6th day of fermentation with mean value of alcohol percentage 2.6 and 4.4 respectively among the different treatment. Significantly highest alcohol percentage of 4.6, 4.8 was obtained at 5th 4th day of fermentation at optimum pH 4.5 and temperature 35 °C respectively. There were significant decreases in total solids during the fermentation of all the treatments. Bioethanol production from palmyrah molasses could be enhanced by the optimization of fermentation condition using the selected yeast strain. Key Words: Ethanol, Molasses, Palmyrah, Yeast, Fermentation
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    Bioethanol Production Using Palmyrah Wastes
    (Uva Wellassa University of Sri Lanka, 2016) Christy, E.J.S.B.A.
    Ethanol is now the most important renewable fuel in terms of market value. Nowadays it is produced from sugar and starch based materials such as sugarcane and corn. However, the second generation of alcohol production also derived from lignocellulosic materials is now being tested in some plants. In this study palmyrah waste material such as molasses, expired pulp and coir dust was selected. Among them molasses and expire pulp used for the primary alcohol production and coir dust used for the secondary alcohol production. Pretreatment of coir duct was carried out with different alkaline and acid solutionat 121 °C for 15 min and H2SO4 was selected as best hydrolysis agent and used for further study. For the H2SO4 pretreatment two factors such as concentration (3%, 5% and 7%) and times (15min, 30min and 45min) were optimized. Among the nine treatments 3% of concentration and 45min were selected as optimum condition for hydrolysis. Coir dust hydrolyzed solution; molasses (°15 initial brix) and expired palmyrah fruit pulp (°15 initial brix) were used for the fermentation. Fermentation was carried out with bakery yeast inoculated with Peptone, yeast extract and nutrient (PIN) medium at room temperature and pH 5.0.The highest significant alcohol production was observed for coir dust H2SO4 hydrolyzed medium (0.4%), molasses (8.6%) and pulp (5.5%) at 4, 6 and 4th day of fermentation respectively. During the fermentation there were significant different in acidity, pH, reducing sugar and total sugar between tested days. Total sugar content was significantly decreased during the fermentation for all waste materials. Bioethanol production could be enhanced by developing enzymatic pretreatment technologies for coir dust and optimization of fermentation medium Keywords: bioethanol, Fermentation, palmyrah, Acid hydrolysis
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    Canning of Palmyrah Young Fruit Kernal (Ice Apple) Using in Palmyrah Sweet Toddy (SAP)
    (Uva Wellassa University of Sri Lanka, 2013) Rinas, U.
    Palmyrah palm (Borassus flbaellifer) is one of the natural vegetative resources of Sri Lanka with significant economic potential and grows extensively in the dried region, predominantly Northern, Eastern provinces. Palmyrah has been called the tree of life as it has contributed in a major manner to the poor classes of people shelter. This study was carried out to develop a cost effective canned Palmyrah fruit (ice apple) product using Palmyrah sweet toddy (palmyrah sap) as the packing medium. The other main objective was investigated the suitable sugar concentration to be used in the medium. Three treatment were tested (1- Brix level -15°, 2- Brix condition-25°, 3- Brix level-35°).Glass jars/bottles were used as the containers and standard canning procedure (filling, exhausting, sealing, retorting) was carried out. All three treatments were treated under the specific temperature (sterilization and pasteurization). Then each heat treatments were compared to find the best temperature in applied in canning process. All treatments shelf stable chemically and microbiologically during the period of study. Sensory evaluation by a trained panel was carried out to select the best treatments in terms of sensory attributes and by statististical analysis of sensory data (Minitab 15). Therefore brix level 25° and sterilization heat treatment were selected. Therefore it was concluded that Brix level 25° best for the product developed. Treatments were determined by sensory analysis method determined. Brix condition 15° and 35° were rejected mainly due to the softening of the texture. Key word- Brix, sterilization and pasteurization, statististical analysis, packing medium
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    Case Study on Waste Water Management Systems Adopted by Different Industries
    (Uva Wellassa University of Sri Lanka, 2015) Jathunge, S.N.
    Different industries discharge waste water with different contaminants in the production process. The heavy metals and other inert materials present in waste water will contaminate the environment by causing normal drainage systems and natural water resources polluted. Therefore, it is a timely need to study detail on potential industries that generate waste water and their adoption measures at present to treat the waste water. With that objective twenty companies that represents eight different industries were identified using secondary data and a structured questionnaire was used to collect data in this study. Data were analyzed by descriptive analysis method using Minitab 17 software. The findings of this study emphasized that different industries have adopted to different waste water management system and analysis methods, however their waste water treatment methods at present are of very expensive. Further cost for water consumption by eight different industries are significantly different in monthly basis and recorded an average of Rs. 4,700,000.00 per month. Among eight different industries and the highest cost recorded in glove industry that costs about Rs. 5,000,000.00 per month. Moreover, 98% of industries prefer to implement a cost effective waste water treatment method in which each industry would be able to reuse the water and enhance the efficiency of water usage in a sustainable way. Key words: Waste water treatments, Heavy metals, Industries, Water reuse
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    Cellulose Whiskers Extracted from Banana Pseudo-Stem as Reinforcing Filler for Natural Rubber Tyre Treads Using Latex Intercalation Method
    (Uva Wellassa University of Sri Lanka, 2014) Bandara, T.A.R.W.M.M.C.G.
    Reinforcing the rubber compounds using cellulose fibre is an emerging trend in rubber industry because of unique physical properties of cellulose fibre. In this study cellulose fibres were extracted from pseudo-stem of banana using alkali treatments and converted into cellulose whiskers (CW) with high pressure defibrillation followed by acid treatment and bleaching. The CW was characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffractometry (XRD) and Particle Size Analyzer. Both FTIR and XRD conforms the cellulose structure. XRD studies showed that the percent crystallinity of bleached fibres is about 69%. The particle size shows a bimodal distribution where approximately 21% of the sample has average size of 110 nm and the rest has the size of 795 nm. The purified CW was intercalated in diluted natural rubber (NR) centrifuged latex in order to prepare CW/NR composites and converted into rubber sheets. Mooney viscosity and stress relaxation coefficient of CW/NR composites were measured. The lowest Mooney viscosity and the highest stress relaxation coefficient were observed in CW/NR composites ensuring higher processability. The compounds were prepared in an internal mixture according to a tyre tread formulation keeping the sample without CW as the control. Cure characteristics were evaluated at 120°C and physical properties were evaluated on par with the ASTM standards. The highest cure rate and better scorch time were observed in CW/NR composite. The density, hardness, resilience, cut & chip and tensile strength of the composite were superior while tear strength and abrasion volume loss were inferior to the control. In overall, it reveals that cellulose whiskers have a great potential to use as reinforcing material for natural rubber tyre tread compounds. Keywords: natural rubber, banana fibre, cellulose nano-whiskers, latex intercalation
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    Cellulose Whiskers Extracted from Banana Pseudo-Stem as Reinforcing Filler for Natural Rubber Tyre Treads Using Latex Intercalation Method
    (Uva Wellassa University of Sri Lanka, 2017) Bandara, T.A.R.W.M.M.C.G.
    Reinforcing the rubber compounds using cellulose fibre is an emerging trend in rubber industry because of unique physical properties of cellulose fibre. In this study cellulose fibres were extracted from pseudo-stem of banana using alkali treatments and converted into cellulose whiskers (CW) with high pressure defibrillation followed by acid treatment and bleaching. The CW was characterized using Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffractometry (XRD) and Particle Size Analyzer. Both FTIR and XRD conforms the cellulose structure. XRD studies showed that the percent crystallinity of bleached fibres is about 69%. The particle size shows a bimodal distribution where approximately 21% of the sample has average size of 110 nm and the rest has the size of 795 nm. The purified CW was intercalated in diluted natural rubber (NR) centrifuged latex in order to prepare CW/NR composites and converted into rubber sheets. Mooney viscosity and stress relaxation coefficient of CW/NR composites were measured. The lowest Mooney viscosity and the highest stress relaxation coefficient were observed in CW/NR composites ensuring higher processability. The compounds were prepared in an internal mixture according to a tyre tread formulation keeping the sample without CW as the control. Cure characteristics were evaluated at 120°C and physical properties were evaluated on par with the ASTM standards. The highest cure rate and better scorch time were observed in CW/NR composite. The density, hardness, resilience, cut & chip and tensile strength of the composite were superior while tear strength and abrasion volume loss were inferior to the control. In overall, it reveals that cellulose whiskers have a great potential to use as reinforcing material for natural rubber tyre tread compounds. Keywords: natural rubber, banana fibre, cellulose nano-whiskers, latex intercalation
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    Coir Fibre Waste as Effective Raw Material for Fibre Boards Reinforced with Natural Rubber Latex Compounds and Phenol-Formaldehyde Resin
    (Uva Wellassa University of Sri Lanka, 2013) Liyanage, W.L.A.M.
    Coir pith is a by-product resulted in extraction of coir from coconut husks. Small fibre particles namely "Kcitu" (-5 mm) are accumulated during coir pith extraction process as a waste material, which has been an issue in the production process. There is a potential to utilize "Kiitu" as an economically viable raw material to manufacture coir boards (CBs). CBs can be used as alternative source for Hard & Particle Boards and other synthetic boards. An effort was made to develop a CB as an alternative to the above boards evaluating the basic parameters. Processing was undertaken using a coir cutter machine and then it was developed in to CB. Each CB (15 x 15 x 0.5 cm) was prepared using 35g of "Kc7tu" changing the mass of Natural Rubber Latex Compounds (NRLC) and Phenol-Formaldehyde Resin (PFR). Mass of NRLC in CBs varied as 30, 40 and 50 g and the PFR as 5, 10, 15 and 20 g. Having moulded, vulcanization was carried out at 120 'C for 20 min. For the CBs, moisture content (%), density (kg m-3), water absorption (%), swelling and physico-mechanical properties such as maximum force at break (N) and maximum elongation (%) were evaluated according to the ASTM and IS standards. Tests were carried out at 27 °C temperature. CBs were prepared successfully by optimizing the composition. The density of CBs was within the acceptabl&'range: 465.8 - 653.61 kg M-3, which is close to the density of 'Hard Boards' and 'Particle Boards'. Moisture content, water absorption and swelling properties were up to the standards. The force at break and maximum elongation showed an increase when the amount of NRLC and PFR was increased. In conclusion, "Katu" can be used as an effective raw material for manufacture of CBs reinfording with NRCL and PFR for the use of other boards given above. Keywords: Coir fibre board, natural rubber, phenol-formaldehyde
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    Compararive Study on Quality Characteristics of Different Palm Treacle and Its Antioxidant Activity
    (Uva Wellassa University of Sri Lanka, 2016) Balasuriyan, A.
    Treacle is any uncrystalised syrup made during the production of sugar. The most common forms of treacle are golden syrup, a pale variety, and a darker variety known as black treacle. Black treacle or molasses has a typically strong, slightly bitter flavour, and a richer colour than golden syrup. Black treacle is obtained from palm such as palmyrah, coconut and kithul, which are available from Jaffna market used as the main sweetening agents for cake, curd, tea and coffee. There is a competition for the selection of nutritionally best treacle for the customers. Therefore this research was design to evaluate the best treacle this contained good physico- chemical and nutritional characteristics. Triplicate treacle samples were obtained from one batch of respective production centers and used for the analysis. All the treacle was obeys SLS specifications while there were significant different among the tested parameters between the treacle. Significantly highest(p<0.05) total sugar (63.90%) and ash content [0.075(+0.002)] was obtained for palmyrah treacle, while protein content was significantly highest for coconut [0.410 (+0.0040] than kithul [0.570(+0.0120] and palmyrah [0.028 (+0.0070)]%.Total phenolic content was significantly highest for coconut [0.807 (+0.004)]while there were no significant different between palmyrah [0.547 (+0.001)] and kithul [0.545 (+0.002)] mg/100g. DPPH scavenging ability with the IC50 values of palmyrah, coconut and kithul were 0.0169 (+0.003), 0.029 (+0.004) and 0.021(+0.004) respectively. Total phenolic contents exhibited significantly positive correlation (0.79, p=0.011) with the IC 50 values of different treacle. The results of this study showed that palmyrah treacle showed highest amount of minerals and antioxidant activity when compared with other palm treacle. Key words: Antioxidant activity, IC 50 Value, Total phenolic content,
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    Comparative Nutrient Analysis of Palmyrah Fruit Pulp with and Without Artificial Preservative
    (Uva Wellassa University of Sri Lanka, 2016) Sivaji, M.
    The study presents the results of a small scale laboratory research carried out to examine the effect of the chemical preservative, sodium metabisulphite (SMS) on the nutritional characteristics of the pulp with time. Palmyrah fruits of same maturity and size from the same palm were subjected to manual extraction of pulp. pH of the pulp was measured and it was adjusted to 3.8 using food grade citric acid. The pH adjusted pulp was then heated to 90° C for 30 minutes using open pan heating and was allowed to cool down to 60° C. Food grade SMS was added to one portion of the pulp in the ratio of 0.4 gram per litre and the other portion of the pulp was not mixed with SMS. Both pulp portions were hot filled into sterilized glass bottles and stored at 4° C in a refrigerator. Continuous nutrient analysis was carried out and the results were subjected to two way ANOVA using Minitab 16 software. Results of the study exhibits that within two months there is a decline in titrable acidity, Na level, moisture level and there is a rise in pH in the pulp with SMS. Furthermore, the abundance of the sugars, protein, fat and K level remained stable throughout the study which lasted for two months. In the pulp without SMS, there is an increase of reducing sugars and titrable acidity and a decline in pH, and total soluble solids levels with time and the differences between the values obtained periodically were significant. Moreover, the microbial colony count shows that the chemical preservation treatment is effective since the colony count is zero in the pulp with SMS at the end of 2nd month, whereas pulp without SMS shows prominent growth of microorganisms and the total plate count here is 55 CFU/ ml at the end of 2nd month. Based on the results of this study there is no adverse effect of SMS on the nutritional composition of the pulp. Addition of SMS shows a strong preservation activity when combined with refrigeration whereas refrigeration alone can be employed to preserve the pulp for up to one month. Key words: preservation, physicochemical properties
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    Comparative Nutritional Analysis of Fresh and Preserved Palmyrah Young Fruit (Ice Apple)
    (Uva Wellassa University of Sri Lanka, 2016) Tharmaratnam, V.
    The study aims to determine the nutritional characteristics of fresh and preserved young fruit kernel of palmyrah and to compare the changes of nutritional characteristics of preserved young fruit kernel with the time. Young fruits of palmyrah which are similar in size and at the same maturity were selected and divided in to two potions. Moisture, total ash, protein, total fat, vitamin C, total sugar, reducing sugar, non reducing sugar, dietary fiber, total phenol content phosphorous, calcium, sodium and potassium content were analyzed for fresh and preserved young fruit kernel. The nutrient analysis was done for one portion as a control. The other portion was immersed in palmyrah sweet sap of which the pH and brix values were adjusted to 4 and 25 respectively. The nutrient analysis was conducted for a period of two months consecutively. The results were analyzed by one way ANOVA at 5 % level of significance using MINITAP 17. Preserved young fruit kernel showed significantly a high fat content [0.083(±0.002)] g/100g and total ash content [0.4250(±0.006)] g/100g compared to those in fresh young fruit kernel. Moisture [89.270(±0.241)] g/100g, protein [0.8375(±0.007)] g/100g and vitamin C [4.9382 (±0.0905)] mg/100g content were significantly high in fresh young fruit kernel compare to those in preserved young fruit kernel. Total sugar [13.8438(±0.054)] g/100g, reducing sugar [3.4632(±0.191)] g/100g and minerals of Ca, Na, K and P were significantly high in preserved young fruit kernel compared to those values of fresh young fruit kernel. There were no significant differences in dietary fiber [0.8709 (±0.010)] g/100g and total phenol content [0.0578 (±0.0006)] g/100g of the fresh and preserved young fruit kernel. Furthermore, the abundance of the moisture, total ash, protein, total fat, vitamin C, total sugar, reducing sugar, non reducing sugar, dietary fiber, total phenol content, and minerals remained stable throughout for two months. Based on the result, it can be concluded that the sweet sap preservation method significantly changed the nutrient characteristics it is compared with fresh young fruit kernel. Therefore further studies are required to identify a better preservation technique. Keywords: Palmyrah young fruit kernel, Palmyrah sweet sap, Preservation
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    Comparative Study of Physico-Chemical Properties of Pb 86 and Rric 121 Clones of Hevea Brasiliensis
    (Uva Wellassa University of Sri Lanka, 2015) Ariyarathna, T.M.S.
    Natural rubber (NR) is a widely used biopolymer, but the variability of its properties is a great disadvantage. The purpose of this study was to investigate the characteristics of physico-chemical properties of latex and coagulated rubbers (unfractionated unbleached crape rubber) prepared from selected rubber clones planted in Sri Lanka. The clone, PB 86 was selected for this study and RRIC 121 clone was used as the control. Properties of NR latex, raw rubber, latex film and gum rubber compound were determined accordance with International Organization of Standards (ISO) specifications. Concentrated latex and unfractionated-unbleached crape rubber from these clones were obtained and latex films and gum rubber compound were prepared respectively. Significant variations (p<0.05) of latex, raw rubber, latex film and gum rubber compound properties among clones were found. Dry rubber content, total solid content and non-rubber content were high in control latex samples. A correlation between Mooney viscosity and Wallace plasticity index (Po) was also found. They were high in PB 86 clone. The increase in Mooney viscosity values was consistent with the increase in Po values. The Plasticity retention index (PRI) value was also high in PB 86 clone. Physico-mechanical properties of the samples: compression set and hardness values were high in RRIC 121 and rebound resilience was high in PB 86 gum rubber compound. It can be concluded that satisfactory physico-mechanical properties were obtained in PB 86 clone that was chosen in the study. Further, the tensile properties PB 86 fulfills the specification for ISO 37: 2011 whereas those of clone RRIC 121 were found to be lower. Keywords: gum rubber compound, Natural rubber, raw rubber properties, physico- mechanical properties, rubber clone
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    Comparative Study of Quality and Nutritional Parameters of Palmyrah Jaggery Produced from Fresh Sweet Sap and Preserved Treacle
    (Uva Wellassa University of Sri Lanka, 2015) Robert, R.
    Palmyrah jaggery is a traditional sweetener and indigenous medicine which is produced by concentrating the unfermented inflorescence sap of palmyrah palm. The palmyrah jaggery obtained after processing is darker and richer in color solid blocks. Palmyrah jaggery has a high demand exists among locally and internationally. Jaggery is produced by sweet sap, is seasonal. To make available throughout the year to consumers, jaggery is produced from preserved treacle to overcome the limitation in the off seasons. This study aims to evaluate whether palmyrah jaggery produced from preserved treacle could deliver quality and nutrient levels comparable to jaggery produced from fresh sweet sap. Palmyrah sweet sap and treacle were collected and two types of jaggery were produced at production unit of palmyrah development board for the analysis. The quality analysis revealed that both type of jaggery were in compliance with SLS 521:1981 specifications while there were significant different (p <0.05) among the tested parameters. The Comparative analysis of macro and micro nutrient composition showed that jaggery produced from fresh sweet sap has (373.83±3.2400) Kcal Energy, (0.8367±0.0252)g/100 g protein and (88.4600±0.4390)g/100 g Total sugar, (18.5000±1.1230) mg/100g Vitamin C content, (0.0440±0.0045) g/100g total phenol significantly higher (p <0.05) than jaggery produced from preserved treacle while there were no significant different (p >0.05) in fat content. The minerals analysis revealed that there were significant differences in all the parameters except sodium content. It can be conclude that jaggery produce from preserved treacle significantly change the nutritional characters it is compared with jaggery produce from sweet sap but as it is comply with SLS 521:1981, preserved treacle could be used to produce the jaggery in the off season instead of jaggery produced from fresh sweet sap. Key Words: Palmyrah Jaggeiy
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    A Comparative Study on Degradability of Nbr And Nr Latex Gloves
    (Uva Wellassa University of Sri Lanka, 2016) Manukularathne, W.G.P.D.
    Natural rubber (NR) and Nitrile rubber (NBR) gloves are two main types of latex gloves used in the personal protective equipment market. In the face of abrupt increase in the demand and usage of these gloves due to the present Covid-19 pandemic, degradation of these gloves after usage may create an environmental threat. Therefore, a study was conducted to compare the degradation behavior of these products. Both glove types were treated under thermal and hydrothermal and UV radiation environments. Untreated samples were used as the control. Under thermal, hydrothermal and photo oxidative treatments, increase of the swelling index of untreated NR gloves (65.2%) increased by 38.23%, 14.69% and 7.17%, respectively while NBR gloves showed an percentage swelling index increment by 14.52%, 15.56% and 12.12% with compered to the percentage of swelling index of the untreated sample (28.77%) in the same order of treatments. The average tensile strength of NR was decreased from 16.89 to 15.67, 11.19, and 15.63 MPa while for NBR it decreased from 28.06 to 24.35, 23.93 and 20.56 MPa after the thermal, hydrothermal and UV exposure, respectively. Hydrothermally treated NR gloves showed new peaks suspected as hydroxyl groups and carbon-carbon triple bonds. Spectra of thermally and hydrothermally treated NBR showed identical loss of the peak responsible for the cyanide group. TGA analysis showed that the initial decomposition temperature of NR has reduced from 365.42 °C to 364.95 °C, 360.63 °C and 365.27 °C, respectively after the thermal, hydrothermal and UV treatments. NBR gloves also showed the same trend except for hydrothermal treatment where an increase in initial decomposition temperature was recorded. Overall, hydrothermal treatment was the best degradation method for NR gloves among candidated systems while exposure to UV radiation exhibited the highest degradation potential for NBR gloves. It was also found that removal of cyanide group when NBR gloves were subjected to hydrothermal degradation. Key words: Fourier transform infrared. spectroscopy; Natural Rubber; Nitrile Butadiene Rubber; Thermo Gravimetric Analysis; Ultraviolet
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    Consumer Preference and Buying Behavior of Branded Coconut Milk Products: a Case in Western Province of Sri Lanka
    (Uva Wellassa University of Sri Lanka, 2014) Dias, M.P.S.H.
    Coconut milk which is obtained from mature coconut kernel is an essential ingredient in Sri Lankans' diet. Since earlier days coconut milk is obtained from fresh coconut nuts and recently different types of readily available coconut milk products have been introduced to the local markets. Study on consumer preference and buying behavior on those coconut milk products is important for consumers as well as production companies. Therefore this study was conducted to identify the factors influence on consumers' preference and buying behavior of coconut milk products. Western province was selected purposively for the study. A questionnaire survey was conducted to gather primary data to analyze the influence of different factors on consumers' preference and buying behavior. Using multistage simple random sampling method 240 individual consumers were selected. Descriptive statistics and binary logistic regression model were used to analyze the data. Main purchase decision maker in food buying process is house wife. According to the results, majority used fresh coconut nuts as a source of coconut milk. Main reason for not consuming coconut milk product is the availability of coconut trees within home gardens. Main reason for use of coconut milk products is its easiness to prepare with short time period. Majority of the respondents aware about the coconut milk products in market and production company, taste of the product, quality of the product, easiness to prepare and availability to purchase are the major factors influencing on consumer buying behavior of coconut milk products. Respondents suggested that increasing the quality of the coconut milk products that will be useful to increase the use of coconut milk products by local consumers. Key words: Coconut milk products, consumer preference, consumer buying behavior
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    Controlling the Maturity of Pre- Vulcanized Natural Rubber Latex Used for Supported Glove Manufacturing
    (Uva Wellassa University of Sri Lanka, 2014) Jayawardhana, H.M.N.H.K.
    Pre-vulcanized natural rubber latex is the major raw material used for production of industrial supported gloves. A process by which crosslinking of the rubber takes place inside particles dispersed in the aqueous serum of the latex can be defined as the latex pre-vulcanization. This latex is subsequently used for dipping to make latex dipped products. Desired crosslinking density of maturation level is needed for manufacturing relevant product. In Industry level when supported glove manufacturing, time taken for the maturation is additional cost and also need to wait until it gets required maturity level for the production. Use of latex compound too early or too late would result in under- curing and over-curing respectively. Due to over maturation of compounds there is high wastage of old compound. In order to overcome that problems inhibition of vulcanization at required level is important. Pre-vulcanization inhibitors (PVI) was used in this study to inhibit the maturity. Even though the salicylic acid and the benzoic acid are tamed as PVI they did not inhibit the maturity of NR pre-vulcanized latex. CTP (N- (cyclohexylthio) phthalimide) which is commonly used in dry rubber industry, has successfully inhibited the maturity maximally for 5 days at the 0.8, 0.9 and 1.0 phr. After 5 days, the pre-vulcanized latex was started to mature gradually. A type of liquid dithiocarbamate accelerator (DTC730) was used as the accelerator in this study. Glove samples were dipped and the abrasion was tested after 156, 204 and 252 hours after adding CTP at 0.8, 0.9 and 1.0phr level. According to the results, best abrasion resistance among dipped gloves were recorded after 156 hours at 0.8 phr level of CTP. Key Words: Pre-vulcanized natural rubber latex, maturation, pre-vulcanization inhibitors.
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    Decrease the Loose Skin Percentage of Natural Rubber Latex Foam Pillow by Using Calcium Carbonate Incorporated Latex Foam
    (Uva Wellassa University of Sri Lanka, 2014) Somarathne, K.E.H.
    The NR latex in Hevea brasiliensis is a colloidal system in which rubber particles are dispersed water. Some rubber products (foam rubber, gloves, condoms, glues, for example) are made directly in latex. The latex is modified for these reasons in order to have higher DRC values (minimum from 60 to 65% of rubber). When producing natural rubber latex foam products, especially in pillow production, there are so many problems happened like defects which are associated with final products such as heat marks, loose skin, rat holes, black marks and etc. In this research study, basically defect of loose skin is consider. Because of temperature, pH like properties and gelling rate become slow. As a result of this problem there is a major defect associated with natural rubber latex foam pillow which is named as Loose Skin. It is a kind of layer separation of top of the pillow. When gelling reaction is occurred, it released hydrofluoride acid and it can react with calcium carbonate and produced carbon dioxide. Therefore, a study was conducted to develop a calcium carbonate included natural rubber latex pillow to find out the maximum calcium carbonate level that can be incorporated into natural rubber latex pillow without affecting its physical properties. By using two separated experiments under the laboratory condition and production condition, I fulfilled my objectives. Under the first experiment, practiced with eight treatment levels having Ophr to 8phr calcium carbonate levels with other compounding ingredients. The most desirable 1, 2 & 3 phr calcium carbonate levels were selected via four common physical properties (hardness, density, air bubble distribution and compression set). Then, they were„used for the second experiment together with the control which has 0% calcium carbonate. In that, most suitable 1 phr calcium carbonate level was selected via four common physical properties (hardness, compression set, mass and defect percentage associated with each phr level). Key words: Calcium Carbonate, Loose Skin, Cushioning Effect, Natural Rubber Latex Foam Pillow, Gelling Agents
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    Defining Suitable Compounding and Processing Parameters to Control Cracks and Splitting in Natural Rubber Coating Supported Gloves
    (Uva Wellassa University of Sri Lanka, 2014) Abeysinghe, M.T.C.
    Latex is defined as a stable dispersion of a polymeric substance in an essentially aqueous medium. Latex compounds can be prepared by adding compounding ingredients. Latex compound maturation is one of the most important aspects and it causes to this cracking and splitting problems. Left over compound-newly pre- vulcanized latex, blend gives the best results. Because blend optimizes the old latex compound aging properties and provide the acceptable levels for the production. Therefore the blend not affecting to the properties of gloves. This research aimed to define the specification for Dry Swelling Index. Dry Swelling Index measures the maturity level of old compound. Through that can be found proper blending ratio to prevent crack and splitting defects formation and also check how many days old compound can used for the sampling. To find out the specification for Dry Swelling Index, dry films were prepared by using unloaded compound sample, dry films were put in to toluene solution and diameter measurements were taken. To find out suitable blending ratio and how many days to keep the sample, Left over compound was taken and mixed with newly pre- vulcanized latex. ) It was found that specification for Dry Swelling Index is in between 72%-96% range. In practice with the time mixing amount of the newly pre-vulcartized latex increases. From those ratios newly pre-vulcanized latex: matured latex compound 20:80, 35:65 and 50:50 ratios were selected. For the company 35:65 ratio is most preferable. Each ratio gives the maximum benefits within 4 days. According to Result of mechanical test (EN: 388). for the company with the 88% Toluene Swelling Index was the most acceptable property for the glove production. By adding newly Prevucanized or immature latex to the old compounds, that can prevent the cracking and splitting defects formation up to some extent. Key Words: Latex compound, Blends, Dry Swelling Index, Toluene Swelling Index, Blending ratio, Defects (cracking, splitting).