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ThesisItem Open Access Investigations on high rate anaerobic bioreactor for energy production from rubber latex processing effluent(Department of Farm Machinery and Power Engineering, Kelappaji College of Agricultural Engineering and Technology,Tavanur, 2020) Megha, A S; KAU; Shaji James, PAgro-processing industries often contribute significantly in pollution due to discharge of untreated effluents. By anaerobic digestion of these organic effluents, methane rich gas can be produced which is suitable to generate electricity and process heat. But conventional biogas plants are slow in operation with long hydraulic retention times of 35 to 40 days which necessitates large digester volumes. So, anaerobic digestion of high volume agro-processing effluents is feasible only through high rate bioreactors which can reduce hydraulic retention time to few hours. Rubber latex processing effluent (RLPE) is a dilute waste water for which high rate anaerobic treatment can be an affordable technology. Hence, an investigation was taken up to study the performance of Up-flow Anaerobic Hybrid Bioreactor for energy conversion of rubber latex processing effluent (RLPE). Physico-chemical characteristics of RLPE samples were tested and found that RLPE was a dilute waste water with pH in the acidic range. BOD: COD ratio of 0.44 obtained in this study showed good biodegradability of RLPE. A batch anaerobic digestion study was conducted as a preliminary experiment to investigate the biomethanation characteristics of RLPE. The experiment consisted of four treatments having different composition of RLPE with inoculums replicated thrice. This study could prove that RLPE could be subjected to biomethanation and cow dung slurry can be used as inoculum. Even at a lower inoculum: substrate ratio of 1:2, the system could be started up yielding substantial amount of biogas coupled with good TS reduction. Performance of field scale Up-flow Anaerobic Hybrid Bioreactors (UAHBR) was assessed by operating them at different HRTs of 10, 7, 5, 3 and 2 day. During the study an interruption of 2 months in operation occurred due to shut down of the processing unit due to Covid 19. After interruption of 2 months reactor recovered within one month and it proved that hybrid bioreactor could be restarted easily after a shutdown for few months. Reactor was stable in operation during 10, 7, 5, 3 and 2 day HRTs and exhibited good process efficiency with better pollutant reduction and biogas production. Performance was seen deteriorated beyond 5 day HRT. The bioreactors were operated successively at reduced loading rates corresponding to the longer HRTs after reaching the shortest HRT of 2 day. It was observed that there was no considerable difference in daily biogas production with the earlier values obtained during the progressive decrease in HRT. This revealed that the bioreactors would have achieved the maximum possible microbial population already and there was no further improvement in performance on further passage of time. The performance parameters obtained in the investigations with field scale reactors were used for evolving guidelines to design a full scale anaerobic bioreactor. The UAHBR performance was quite satisfactory at 5 day HRT with respect to pollutant reduction as well as energy production. Hence as criteria, full scale plant was proposed to be operated at 5 day and the corresponding reactor volume was 27 m 3 with 7.2 m 3 gas holder volume. The biogas expected to be produced from the full scale plant can be used in a biogas fired rubber sheet dryer which can save about 500 kg of fire wood per day currently used for drying rubber sheets.ThesisItem Open Access Tank mix application of cyhalofop-butyl with selected herbicides for weed control in wet seeded rice(College of Horticulture, Vellanikkara, 2016) Atheena, A; KAU; Prameela, PHerbicidal weed control is very common in rice cultivation. Application of pre- emergence and post emergence herbicides or two post emergence herbicides as follow up sprays is usually recommended to take care of diverse weed flora in rice. As this increases the cost incurred in spraying, farmers prefer single spray of a mixture of herbicides or a broad spectrum herbicide. Cyhalofop-butyl is a common cost effective post emergence selective herbicide that controls grass weeds, especially the rice associated weed Echinochloa spp. and Leptochloa chinensis. The present study was carried out to study the efficacy and economics of tank mix application of cyhalofop-butyl with selected herbicides (pre emergence, post emergence and early post emergence) and to study the response of weed flora to tank mix application. A field experiment was conducted in Alappad kole lands from September 2015 to January 2016, using the rice variety Uma (MO-16). There were a total of 16 treatments replicated thrice. Almix® [chlorimuron-ethyl (10%) + metsulfuron-methyl (10%)], ethoxysulfuron, carfentrazone-ethyl, pyrazosulfuron-ethyl, pretilachlor, pendimethalin were tank mixed with cyhalofop-butyl and were also applied as follow up sprays, two days after cyhalofop-butyl application. For better comparison, sole application of cyhalofop-butyl, as well as a broad spectrum post emergence herbicide, bispyribac sodium, were also included apart from hand weeded and unweeded controls. Pre emergence herbicides were sprayed at six days after sowing (DAS), and early post emergence herbicide at 10 DAS. All tank mix herbicide applications were done at 18 DAS and follow up post emergence herbicide applications at 20 DAS (i.e., two days after the application of cyhalofop-butyl). Hand weeding was carried out at 20 DAS and 40 DAS. The data on weed spectrum revealed that broad leaf weeds and grasses were dominant and at 30 DAS they constituted 47 per cent and 46 per cent of the population respectively, whereas sedges constituted only 7 per cent. Echinochloa stagnina was the dominant grass and Monochoria vaginalis, the dominant broad leaf weed. Among tank mix applications of herbicides, cyhalofop-butyl + pyrazosulfuron-ethyl recorded the least weed dry matter production while among various sequential application of herbicides, the lowest weed dry matter accumulation was noted in cyhalofop-butyl followed by (f.b.) Almix® and both were statistically comparable. Among various herbicides and herbicide mixtures, both tank mix and sequential applications of carfentrazone-ethyl caused severe phytotoxicity in rice. However, the crop recovered by seven days after spraying and plant growth parameters were not affected with all the treatments registering comparable plant height at all stages. At both 30 DAS and 60 DAS, hand weeded treatment registered the highest tiller count. However, this was on par with bispyribac sodium, pyrazosulfuron-ethyl + cyhalofop-butyl and cyhalofop-butyl f.b. Almix®. Highest and statistically superior grain yield was registered in hand weeded treatment. Application of cyhalofop-butyl + pyrazosulfuron-ethyl and bispyribac sodium were the next best treatments with respect to grain yield and were superior to all other treatments. Except for pyrazosulfuron-ethyl all other herbicides resulted in lower grain yields when tank mixed with cyhalofop-butyl with weed index in the range of 13to 18 per cent and weed control efficiency in the range of 61 to 76 per cent (at 30 DAS). Application of follow up sprays of herbicides for control of broad leaf weeds after cyhalofop-butyl resulted in grain and straw yields comparable to that of single application of bispyribac sodium, which recorded a higher B:C ratio of 2.4. From this study it can be concluded that tank mix application of cyhalofopbutyl with pyrazosulfuron-ethyl at 18 DAS can be recommended for effective control of mixed weed flora in wet seeded rice as this treatment resulted in the highest B:C ratio (2.5) as well as net returns. It is not advisable to go for tank mixing of cyhalofop-butyl with Almix® as it will lead to complete loss of activity of cyhalofopbutyl. Tank mixing of pre emergence herbicides with cyhalofop-butyl was found to be less effective than their sequential application.ThesisItem Open Access Development of an extruded product from raw jackfruit(College of Agriculture, Vellayani, 2015) Veena, Kumari; KAU; Suma, DivakarThe study, entitled “Development of an extruded product from raw jackfruit was carried out at the Department of Home Science, College of Agriculture, Vellayani, during the period 2013-15. The main objective of the study was to develop an extruded product viz. noodles from raw jackfruit and ascertain its physical, chemical, nutritional, cooking and shelflife qualities. The preliminary processing methods for development of the product were standardised. Thus, dimensions of bulbs and seeds, blanching and boiling time and immersion in various pre-treatment media for different durations of time were identified. Raw jackfruit bulbs and seeds were processed into flour and their quality was evaluated. Analysis of nutritional and chemical quality revealed that seed flour had higher levels of nutrients than bulb flour; energy (353 kcal), protein (10.48g), carbohydrate (81.46 g), magnesium (338.04 mg), calcium (308.56 mg), sodium (60.63 mg) and potassium (1478.37 mg). The nutrient composition of bulb flour was analysed for energy (329 kcal), carbohydrate (74.12g), protein (1.53 g), calcium (30 mg), sodium (35.06 mg), magnesium (0.13 mg) and potassium (328.11 mg) in hundred grams (dry weight basis). Shelf life quality revealed that bulb flour is more stable with respect to moisture, insect and microbial infestation. Six treatments comprising of different combinations and proportions of refined flour, jackfruit bulb and seed flour were tried out for processing of noodles. These composite flour combinations formed the base material for noodles. Noodles were extruded with the Barbender single screw extruder at CTCRI Sreekaryam, Thiruvananthapuram. The physical characteristics ascertained for the products were- colour, bulk density, true density, swelling index. Extrusion behaviour was evaluated with respect to three parameters namely residence time, appearance and uniformity of strands. Whiteness index (an indicator of colour) ranged from 66.20 to 85.36. Treatment T3 (5:3:2) had revealed higher bulk density (0.91g/cm3) while treatment T6 (5:2:3) showed the least value (0.78g/cm3). The lowest value for swelling index (1.05) was obtained for the treatment T5 (5:1:4) while T4 (5:4:1) was seen to have the highest value for swelling index (1.46). No significant difference for true density was observed among the treatments. Cooking characteristics analysed were cooking time, cooking loss, cooked weight and water absorption. When T6 recorded lowest time for cooking (8.26 min), T4 took the highest time (9.36 min). Cooking loss ranged from 9.13 to 15.37%. T4 was observed to have the highest cooked weight (24.62g) and T7 (commercial noodles) had the lowest (19.87g). There was variation with respect to nutrients in all treatments. Among the developed noodles calorie (380 kcal), carbohydrate (70.91) and protein (13.49) content was highest in T5. On organoleptic analysis, T5 obtained the highest values with respect to appearance (4.59), colour (4.77), texture (4.89), and taste (4.87) and over all acceptability (4.78). These values were seen to be lower than the values of control but this difference was not statistically significant. When the products were packed and kept for storage for 3 months in HDPE and laminated pouches, it was observed that moisture, microbial contamination, sensory qualities did not show significant change irrespective of packaging material. Physical characteristics, shelf-life parameters, nutrient and chemical profile, were seen to be on par among the treatments. However T5 and T6 can be recommended with respect to better sensory qualities. (Refined flour, jackfruit bulb flour and jackfruit seed flour in the ratio of 5: 1: 4 and 5: 2: 3). From the above study, it can be concluded that noodles with high consumer acceptability can be developed from this underexploited fruit, which has good nutritional, organoleptic and shelf life qualities.ThesisItem Open Access Process standardisation for banana wine(College of Horticulture, Vellanikkara, 2011) Saritha, E V; KAU; Usha, VThe study on “Process standardisation for banana wine” was undertaken to evaluate the physico chemical and sensory qualities of banana (Palayankodan) wines with pure strains of wine yeast Saccharomyces cerevisiae and commercial baker’s yeast. Since, composition and quality of a wine was closely related to the yeast strain used, standardisation of banana wines with yeast strains was an objective of the study. In the present study, three pure strains of Saccharomyces cerevisiae viz MTCC 172, MTCC 174 and MTCC180 were obtained from IMTECH and the commercial baker’s yeast were used each in two different dilutions (106 and 107) for fermentation of banana pulp. Inoculum concentration was standardised by standard procedures before fermentation. Wine yield was significantly high with baker’s yeast in both 106 dilution (68.36%) and 107 dilution (67.76%). Among pure strains, wine yield was high with MTCC 172 in both dilutions (59.53 and 57.57% respectively). MTCC 172 (106) also produced wines with significantly high TSS (13.93° brix) and high pH (4.25). Among wines with baker’s yeast, T7 (106 dilution) showed highest wine yield (68.36%), alcohol content (8.23%) and TSS (12.46° brix) with a corresponding high titrable acidity of 0.89 per cent and low pH (3.74). Clarity of wine was maximum (T8) with baker’s yeast (78.75% light transmittance) in 107 dilution. Sensory qualities of the wines with yeast strains revealed that the panelists were in agreement only with the high flavour profile of the wines. Among pure strain, MTCC 172 (106) dilution had the maximum score for colour and appearance (8.1), flavour (8.1), taste (7.9) and overall acceptability (7.8). Among wines with baker’s yeast, T7 (106 dilution) showed the best score for colour and appearance (8.4), flavour (8.2) and overall acceptability (7.6). Based on the overall acceptability score of the wines, pure strain MTCC 172 (106 dilution) and baker’s yeast in 106 dilutions were selected for wine development. Another objective of the study was to evaluate the effect of various treatments on the quality attributes of wines developed by the selected yeast strains. Treatments with pectinase enzyme, potassium metabisulphite (KMS) and pressure cooking of banana pulp as a pretreatment were done to evaluate the quality aspects of wines. Among treatments with MTCC 172, T2 (pulp + sugar + PS + enzyme) and T8 (pressure cooked pulp + sugar + PS + enzyme + KMS) were selected with maximum overall acceptability score (7.9). Among treatments with baker’s yeast, the selected treatments with acceptable quality parameters were T2 (pulp + sugar + BY + enzyme) and T4 (pulp + sugar + BY + enzyme + KMS) with the highest overall acceptability score of 7.8 and 7.7 respectively. All the four selected wines were treated with pectinase (0.3%). The selected wines after initial quality evaluation were pasteurised and bottled in amber coloured bottles with cork caps and were stored in ambient temperature for three months for storage studies. The physico chemical characteristics of the wines showed a significant increase in clarity, titrable acidity, tannin and a significant reduction in reducing sugar. Maximum wine clarity, titrable acidity and maximum reduction in reducing sugar were found in T2PS. With respect to organoleptic qualities, there was no significant change with regard to colour and appearance, taste and overall acceptability of the wines in storage. A significant increase in flavour, desirable level of astringency and acceptable level of alcohol were observed in T2PS (pulp + sugar + PS + enzyme) after storage. Organoleptic qualities after storage revealed a high score for T2PS in attributes like desirable level of astringency (7.9), sugar acid blend (8.1), taste (8.2), acceptable level of alcohol strength (8.0) and overall acceptability (8.1). After storage there was no microbial population (yeast, bacteria and fungi) in the wines. The cost of production of the selected wine treatment T2PS (pulp + sugar + PS + enzyme) was worked out and was compared with the cost of 750 ml of grape wine locally available made by wine makers. Grape wine (750 ml) costs Rs.150/- whereas the banana wine costs Rs. 96/-. The cost can be reduced further in large scale production of banana (Palayankodan) wines