http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/5699 2026-04-04T09:58:32Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/1443 Determination of Quality of Parboiled Rice by Adapting Different Processing Practices in Jaffna Peninsula Prabhaharan, M.; Alvaappillai, P. Parboiling is a hydrothermal treatment applied before milling in order to increase milling recovery by minimizing broken rice percentage in the end product. Parboiling has three stages namely soaking, steaming and drying. Soaking and steaming play a key role to harden paddy grains by changing physical properties. Therefore, quality determination of end product is important. Effect of soaking and steaming duration on rice quality was investigated with respect to parboiling process. One kilogram of paddy was taken as sample. There were five treatments assigned with three replicates such as un-soaking and un-steaming, soaking and un-steaming, soaking and steaming an hour, soaking and steaming 2 hours soaking and steaming 3 hours. Soaking duration 12 hours at 30 oC was kept constant for all treatments. Machines were used on husking, milling and polishing of rice for analytical grade to evaluate the percentages of de-husked yield, head rice yield and broken rice yield, respectively. Lab scale detectors were used to count the quality attributes of white belly, heat damaged grains and whiteness value, which reflected the appearance of final processed product in local markets. Among the treatments, higher yield of dehusking rice, milling rice recovery and less percentage of broken rice were 78.4 %, 65.18 % and 11.9 %, respectively and obtained from the treatment of soaking 12 hours at 30 oC and steaming 2 hours of duration. The results revealed that steamed with two hours duration had given very less white belly, whereas un-soaked steamed rice kernel had highest percentage of white belly. The percentage of damaged grains by heat increased with the increasing the duration of steaming. There was significant difference on degree of de-husking, milling and broken percentage at 5% alpha level among treatments in un-soaked, un-steamed, soaked-un-steamed and soaked-steamed. Sample of Un-soaked with un-steamed had highest whiteness value while soaked with steamed samples yielded lowest whiteness values From these results, it can be concluded that the parboiling process has to be designed with soaking and steaming strategies to minimize the percentage of broken rice at the end product. 2016-01-01T00:00:00Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/1440 Impact of Alternative Wetting and Drying on the Soil Surface Organic Matter in a Lowland Paddy Field Sellathurai, T.; Kamaleswaran, S; Galagedara, L.W.; Mowjood, M.I.M. Ponded water in lowland paddy cultivation has a role on soil biomass accumulation, decomposition, and nutrient availability. However, alternative wetting and drying (AWD) is a common phenomenon under minor irrigation systems due to scarcity of water. The AWD process may have an effect on the soil organic matter (SOM). Therefore, the effect of several cycles of varying length of AWD conditions on SOM content at the soil surface was investigated by using Lysimeter for a period of 98 days. The experiment design was complete randomized design with 4 treatments; i.e. 4 days dry spell (T1 ), 12 days dry spell (T2 ), 20 days dry spell (T3 ) and 4 days dry spell with paddy (T4 ). Soil samples from the surface were collected at 14 days interval and the SOM contents were measured. Results show significant differences among the treatment combinations. The accumulation of SOM after AWD water management practices is higher for T1 followed by T2 , T3 and T4 . The surface SOM content has reduced by 19 %, 53 %, 86 % and 49 % of the initial SOM content for T1 , T2 , T3 and T4 , respectively. Shorter dry spells enhance the organic matter accumulation compared to longer dry spells by creating anaerobic condition. On the other hand, organic matter degradation is higher in longer dry spells due to aerobic condition. This finding may help to take decisions on correct water management practices to optimize organic matter dynamics in lowland paddy fields. 2016-01-01T00:00:00Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/1438 In-vitro Assessment of Antifungal Activity of Aloe vera Leaf Powder Extracts Against Banana Pseudostem Rot Fungi, Marasmiellus spp Nivethika, A.; Mikunthan, G. Being an important medicinal plant, Aloe vera is important in industrial perspective as well as traditional usage. The antifungal activity of A. vera leaf powder extracts were assessed against banana pseudostem rot fungi, Marasmiellus spp. Leaf powder with acetone and ethanol extracts of 20, 200, 400, 1000 and 2000 μL were administered to assess the inhibition of colony growth of Marasmiellus spp. The experiment was conducted in a CSompletely Randomized Design. In A. vera acetone extract, first day after inoculation, inhibition percentage of the Marasmiellus spp was higher (74.53 %) in 2000 μL and the lowest percentage (23.53 %) of inhibition was obtained in 20 μL of A. vera acetone extract. The similar highest and lowest percentage of inhibition were observed in second, third and fourth day after inoculation. In A. vera ethanol extract, complete (100 %) inhibition was observed in 1000 μL and 2000 μL extracts. The lowest inhibition (2.26 %) was recorded in 20 μL of A. vera ethanol extract. Among the 1000 μl and 2000 μL leaf extracts, ethanol extract had the highest inhibition percentage compared to A. vera acetone extract. These findings are useful to prepare the extracts of A. vera leaf powder for the management of Marasmiellus spp. 2016-01-01T00:00:00Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/1435 Development of Bilimbi (Averrhoa bilimbi L.) Powder: Physicochemical, Microbial and Organoleptic Qualities Nilugin, S. E.; Mahendran, T. Underutilized plant species are defined by their unexploited economic potential, making them an appropriate focus for commercialization. Fruits of these plants are an important supplement to human diet as they provide the essential minerals, vitamins and fibre required for maintaining health. A research was conducted to develop bilimbi fruit powder with good nutritional qualities and to assess the shelf life. Unripe mature bilimbi fruits were collected, washed and cut into 12 mm thick slices. The slices were dipped into potassium metabisulphite solution of 0.05 % (w/v) for 5 minutes. These slices were placed in a single layer on trays, dried in sun for 18 hours and in dehumidifier at 40 °C, 50 °C, 60 °C and 70 °C for 16, 14, 12 and 10 hours, respectively and ground into powder. The developed powders were assessed for physico-chemical, microbiological, sensory qualities and shelf life. Physico-chemical analyses revealed that among the tested treatments the powder developed from the unripe bilimbi dried at 50 °C had 3.4 % of moisture content, 1.4 % of fibre, 10.9 % of tritratable acidity (as % oxalic acid), 20.8 mg/100 g of ascorbic acid and 11.3 % of total sugar content. Microbiological analysis indicated that there was no total plate count observed in the tested treatments. Sensory attributes showed that powder developed from the unripe. bilimbi dried at 50 °C was most preferred based on the organoleptic characteristics. Among the treatments, the bilimbi powder obtained from the unripe bilimbi dried at 50 °C for 14 hours had the highest shelf life which could be preserved minimum of six months without any significant changes in the quality characteristics. 2016-01-01T00:00:00Z