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ThesisItem Open Access Development of functional jackfruit pasta(Department of Post Harvest Technology, College of Agriculture,Vellayani, 2019) Swathi, B S; KAU; Geetha lekshmi, P RThe present study entitled “Development of functional jackfruit pasta” was carried out at Department of Post Harvest Technology, College of Agriculture, Vellayani during the period 2017-2019 with the objective to develop functional pasta from jackfruit bulb and seed flour enriched with vegetables and to study the storage stability. Jackfruit bulb and seed flour were used for the development of jackfruit pasta in different combinations along with cassava flour replacing a portion of refined flour contributing to 65% of total ingredients. The remaining 35% of total ingredients were kept as constant with refined flour, soy flour and starch. Jackfruit pasta developed were subjected to analysis for cooking quality, nutritional, textural and sensory parameters. Cooking quality characters viz. cooking loss, water absorption, swelling index and cooking time were analyzed for jackfruit pasta and cooking loss ranged from 14.16% to 21.97%. The lowest cooking loss (14.16%) was recorded for jackfruit pasta developed with 15% jackfruit bulb flour, 15% jackfruit seed flour and 35% cassava flour. Water absorption and swelling index of jackfruit pasta increased with increase in seed flour concentration and the highest water absorption (1.34 g g-1) and swelling index (2.86%) was observed for 50% jackfruit seed flour and 15% cassava flour combination. Cooking time of developed jackfruit pasta ranged from 6.12 min to 7.14 min with no significant difference among the treatments. Nutritional parameters viz. starch, total sugar, reducing sugar, protein, carotenoids, crude fibre and antioxidant activity were analyzed for raw as well as cooked jackfruit pasta which varied with jackfruit bulb and seed flour concentration. Starch and protein content of jackfruit pasta increased with increase in seed flour and cassava flour concentration and total sugar, reducing sugar and carotenoids increased with bulb flour concentration. Sensory evaluation of developed jackfruit pasta exhibited significant difference in consumer acceptance for the treatment combinations. Based on cooking quality, nutritional, textural and sensory parameters the three best treatments viz. jackfruit bulb flour (10%) + jackfruit seed flour (30%) + cassava flour (25%), jackfruit bulb flour (25%) + jackfruit seed flour (25%) + cassava flour (15%) and jackfruit bulb flour (20%) + jackfruit seed flour (20%) + cassava flour (25%) were selected for further studies. The best three jackfruit pasta combinations selected were incorporated with three vegetables viz. carrot, beetroot and red amaranthus @ 5 and 10 % and the developed functional jackfruit pasta were subjected to cooking quality, nutritional, textural and sensory analyses. Cooking loss, swelling index and cooking time did not show significant difference among the combinations. Water absorption of vegetable incorporated jackfruit pasta @ 10% recorded the highest value of 1.49 g g-1 and 1.68g g-1 for the combination of 10% jackfruit bulb flour, 30% jackfruit seed flour and 25% cassava flour with 10% amaranthus and beetroot respectively while it was 1.53g g-1 for the combination of jackfruit bulb flour (25%) + jackfruit seed flour (25%) + cassava flour (15%) with 10% carrot. Carrot incorporated functional jackfruit pasta with 25% jackfruit bulb and seed flour, 15% cassava flour and 10% carrot recorded the highest consumer acceptance followed by beetroot and amaranthus based functional jackfruit pasta with 10% jackfruit bulb flour, 30% jackfruit seed flour, 25% cassava flour and 10% respective vegetables. The selected vegetable based functional jackfruit pasta were stored at room temperature and storage stability studies on cooking quality, nutritional and sensory attributes revealed that there was no significant change in qualities during storage and no microbial load was found till the end of storage period of four months. In the present study, combinations for development of vegetable based functional jackfruit pasta were standardized as 25% jackfruit bulb flour, 25% jackfruit seed flour, 15% cassava flour and 10% carrot for carrot based functional jackfruit pasta and the combination of jackfruit bulb flour (10%) + jackfruit seed flour (30%) + cassava flour (25%) and 10% beetroot or amaranthus for beetroot and amaranthus based functional jackfruit pasta. Storage stability studies on cooking quality, nutritional and sensory attributes revealed that there was no significant change in qualities during storage and no microbial load was found till the end of storage period of four months.ThesisItem Open Access Characterization and value addition of male buds of banana cultivars(Department of Post Harvest Technology, College of Horticulture, Vellanikkara, 2019) Thanzeela Hoorlin, K A; KAU; Meagle Joseph, PIndia is the largest producer of banana in the world and Kerala is rich with wide array of banana varieties. The banana plant in whole is useful for its fruits, peel, fibre, corm, male bud and pseudo stem. Banana inflorescence also known as navels is removed in commercial banana cultivation, by a practice called denavelling, for quality assurance of fruits. These male buds loaded with lots of nutrients are used as vegetable and also for the preparation of nutraceuticals. The stages of harvest after bunch emergence influence the quality of the male bud. Hence the study was carried out in the Department of Post-Harvest Technology, during 2017-2019,with the objectives to characterize the male buds of banana cultivars and to standardize their harvesting stage, packaging and storage methods and minimal processing techniques . Palayankodan, Grand naine, Njalipoovan and Nendran varieties of banana were selected for the first experiment. They were harvested at 15, 20 and 25 days after full bunch emergence (DAB) and characterized based on physico-morphological and biochemical parameters. Palayankodan and Grand naine had the highest bud weight, length and diameter when harvested at 20 DAB and Nendran at 25 DAB. The recovery and firmness was found to be highest when harvested at 25 DAB in Palayankodan and at 15 DAB in Grand naine and Nendran. However, Njalipoovan had the highest value for all the four parameters (275 g weight, 19.8 cm length, 20.4 cm diameter, 87.2 % recovery) when harvested at 15 DAB. Considering the biochemical parameters, in all the four varieties the desirable constituents like carbohydrate, protein, dietary fibre, potassium etc. were found to be highest when harvested at 15 DAB. When subjected to organoleptic evaluation, Palayankodan had the overall consumer acceptance and highest total score under all the three stages of harvest. Also due to its popularity and easy availability, Palayankodan variety was selected for the packaging and storage studies. In the second experiment, banana male buds were given different packaging treatments (wrapping in shrink film, cling film and perforated polyethylene cover) and stored under ambient, cold storage and refrigerated conditions. Physico chemical changes and organoleptic quality were observed. The studies revealed that banana male buds packed in polyethylene cover of 150 gauge and stored under refrigerated condition had the highest shelf life (43 days) and lower physiological loss in weight along with biochemical parameters like ascorbic acid (11.9 mg/ 100g) and total phenols (0.648 mg/ 100 g). Also it had scored highest in organoleptic evaluation with a total of 36.07. Third experiment consisted of standardizing minimal processing techniques for banana male bud. An attempt was made by adopting different pre-treatments (0.2 % ascorbic acid, 0.2 % citric acid, 0.2 % turmeric + salt) and packaging methods ( paper plate overwrapped with cling film, polystyrene trays overwrapped with cling film, polyethylene punnets) to enhance the shelf life and to improve the market value of sliced banana buds. Minimal processed buds with 0.2 % citric acid pretreatment packed in polystyrene trays had a shelf life of one week and microbial load within the permissible limit along with better retention of ascorbic acid (6.81 mg/ 100g) and total phenols (0.276 mg/ 100 g). The present study found that the harvesting stage of buds in Palayankodan and Grand naine was 20 days after full bunch emergence and in Njalipoovan and Nendran it was 15 and 25 days after full bunch emergence respectively. The buds of all four varieties are nutrient rich and organoleptically acceptable with mean rank scores above 6. Packaging in perforated polyethylene cover and storage under refrigerated condition increases the shelf life of whole male bud with retention of desirable qualities. Also 0.2% citric acid pretreatment and packaging in polystyrene trays enhance the market value of minimal processed buds.ThesisItem Open Access Standardization of quality wine production from selected underexploited fruits(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2019) Keerthana Das; KAU; Mini, CThe study entitled “Standardization of quality wine production from selected underexploited fruits” was conducted at Department of Post Harvest Technology, College of Agriculture, Vellayani, Thiruvananthapuram, during the year 2017-2019 with the objective to standardize quality wine production technology from selected underexploited fruits of Kerala. Fruit wines were prepared from four different underexploited fruits viz., carambola, papaya, jamun and rose apple independently by varying three process parameters viz., fruit: water ratio, yeast concentration and clarification methods. Fruit: water ratio was tried at 1:0.75, 1:1 and 1:2; yeast concentration at 0.5, 0.75 and 1% and clarification by pectinase enzyme and by settling, thus formed 18 different wines in each fruit. The experiment was conducted as four continuous steps viz., production of fruit wines, quality evaluation, selection of the best wine and studying the storage potential of wines. Among the four underexploited fruits, carambola, papaya and rose apple produced wines of acceptable quality. No significant difference was noticed in the TSS content of different wines. All the prepared wines were “dry” due to absence of residual sugar content. Carambola wines were golden yellow, brilliant to cloudy with a predominant astringent taste and 7.2 to 12.3% alcohol content. Papaya wines were light yellowish with a characteristic papaya odour and their alcohol content ranged from 6.15 to 17.28%, whereas rose apple wines were light pinkish, brilliant with 5.27% to 12.01% alcohol. The wine with high antioxidant potential and high overall acceptability was selected from each fruit for conducting storage trials. The highest mean overall acceptability score (6.1) was obtained for the carambola wine prepared using 1:2 fruit: water ratio, 0.75% yeast and clarified by pectinase. This wine was brilliant, had 4.60 TSS, 0.5% acidity, 8.9% alcohol, 183.63 mgg-1 polyphenol and the highest antioxidant activity (64.9 %). Papaya wine prepared using 1:2 fruit: water ratio, 1% yeast and clarified by pectinase had the highest antioxidant activity and high polyphenol content with an overall acceptability score of 4.6. This brilliant wine had 30 TSS, 0.46% acidity, 6.15% alcohol, 201.57 mgg-1 polyphenol and 79.46 % antioxidant activity. The highest mean overall acceptability score (5.4) was obtained for the rose apple wine prepared using 1:2 fruit: water ratio, 0.75% yeast and clarified by settling. It was brilliant, with 5.60 B, 0.44% acidity, 9.08% alcohol, 97.79 mgg-1 polyphenol and the highest antioxidant activity (91.56 %). The processing variables tried in the present experiment resulted in a dark purple attractive but unacceptable beverage from jamun with high alcohol (6.44 to 24 %) and acidity (0.69 to 5.42%), pungent smell and vinegary taste; hence could not be subjected to sensory analysis and further storage studies. In general, wines prepared from 1: 2 fruit: water ratio had superior quality, acceptability and highest antioxidant activity. Addition of 0.5% yeast was not sufficient for producing quality wines. When yeast concentration was increased to 0.75%, the brilliancy and acceptability of the wines increased and at 1%, cloudiness enhanced resulting in reduced acceptability. Use of pectinase enzyme was essential for clarifying papaya and carambola wines where as clarification by settling could give a brilliant quality wine from rose apple. The best wine selected from each fruit was stored under ambient condition for a period of three months in plain and amber coloured glass bottles for analysing their storage stability. The polyphenol content of the wines decreased during storage in both the containers and the percentage reduction was less in amber containers indicating better retention of quality parameters. The alcohol content increased during storage and the percentage increase was more in amber containers. There was no significant difference in the microbial load of wines stored in different bottles or different storage periods. The present study highlighted the fermentation capabilities of three underutilized fruits of Kerala and standardized quality wine production from them. It was proved that the wine processing parameters should be formulated for different raw materials based on their initial characteristics for production of acceptable quality wines.ThesisItem Open Access Development of osmo dehydrated red banana(musa spp)(Department of post harvest technology, college of agriculture, Vellayani, 2019) Archana, A K; KAU; Geetha lekshmi, P RThe present study entitled “Development of osmo dehydrated Red Banana (Musa spp.)” was carried out at the Department of Post Harvest Technology, College of Agriculture, Vellayani during the period 2017-2019 with the objectives to standardize different process variables viz., fruit slice shape, osmotic concentration and immersion time for osmo dehydration of red banana and to assess the storage stability of osmo dehydrated product. Good quality uniform sized, fully ripe red banana were sliced into three shapes viz., ring, round and chunks of thickness 5 mm and osmosed in sugar syrup of 40oBrix, 60oBrix and 80oBrix concentration with an immersion time of 60, 120 and 180 minutes. After the osmotic treatments, the samples were analysed for different mass transfer characters. The osmosed red banana slices were finally dehydrated in a cabinet drier at 50oC till the product attained a moisture content of 17(+1)% and analysed for biochemical, physical and sensory quality parameters. Mass transfer characters viz., solid gain, water loss and percentage weight reduction increased with increase in osmotic concentration and immersion time irrespective of fruit shapes. Maximum solid gain (8.90%), water loss (9.59%) and weight reduction (10.00%) with a water loss to solid gain ratio of 1.07 was observed in osmo dehydrated red banana chunks at an osmotic concentration of 80oBrix with 180 minutes immersion time. Biochemical characters viz., TSS, total sugar and reducing sugar increased with increase in osmotic concentration and immersion time whereas acidity, vitamin C, antioxidant activity and carotenoid content decreased. Osmo dehydrated red banana rings recorded a TSS of 59.49oBrix, total sugar of 52.27%, reducing sugar of 36.63%, 8.33 mg 100g-1 vitamin C, 0.68% acidity, 94.54% antioxidant activity and 6.00 µg 100g-1 carotenoids and it varied with shapes. Physical characters viz., yield, rehydration ratio, textural quality and colour were analysed. The highest yield (31.75%) was observed for osmo dehydrated red banana chunks at 80oBrix and 180 minutes immersion time and it was 30.37% and 29.58% for ring and round slices respectively. The lowest hardness (1.24 kg) and cutting energy (0.72 kg s) was noticed in osmo dehydrated red banana chunks at 80oBrix and 180 minutes immersion time. Sensory evaluation of osmo dehydrated ring, round and chunk shaped slices were conducted and kruskal wallis test confirmed significant difference among the treatments for sensory attributes. Osmo dehydrated red banana rings, rounds and chunks recorded the highest acceptance for all the sensory attributes at 80oBrix for an immersion time of 180 min. Based on the mass transfer, biochemical, physical and sensory analysis, three best treatments; one from each shape were selected (ring, 80oBrix, 180 min; round, 80oBrix, 180 min and chunks, 80oBrix, 180 min). The best treatments selected were subjected to 2% and 4% corn starch treatment and sensory analysis revealed that corn starch treated samples were not acceptable when compared with untreated samples. The three selected osmo dehydrated red banana were packed in 200 gauge polypropylene and stored at room temperature were analysed for biochemical, microbial and sensory qualities at monthly interval for four months. During storage, 3.26% increase in TSS (53.73oBrix to 55.48oBrix), 4.62% increase in total sugar (53.72% to 56.20%) and 6.70% increase in reducing sugar (37.30% to 39.80%) were observed whereas a decrease of 51.61% in acidity (0.62% to 0.30%), 10.11% in vitamin C (9.59 mg 100g-1 to 8.62 mg 100g-1), 2.86% in antioxidant activity (93.85% to 91.17%) and 28.59% reduction in carotenoid content (7.52 µg 100g-1 to 5.37 µg 100g-1) was observed. Sensory qualities of the product decreased slightly with the advancement of storage period and osmo dehydrated red banana rings recorded the highest consumer acceptance followed by chunks and round shaped slices. No microbial growth was found till the end of storage. In the present study, process variables were standardised for the development of osmo dehydrated red banana. Sugar syrup as osmotic solution at a concentration of 80oBrix with an immersion time of 180 min was recorded as the best treatment for osmo dehydration for all the three shapes of red banana slices viz., ring, round and chunks. Better consumer acceptability was recorded for osmo dehydrated red banana rings followed by chunks and round slices. Storage stability studies revealed that osmo dehydrated red banana packed in 200 gauge polypropylene could be stored for four months at room temperature without loss in quality.ThesisItem Open Access Feasibility of puza zero energy cool chamber as low cost on-farm storage structure under Kerala condition(Department of post harvest technology, college of agriculture, Vellayani, 2019) Lekshmi, S G; KAU; Mini, CThe experiment entitled “Feasibility of Pusa Zero Energy Cool Chamber as low cost on-farm storage structure under Kerala condition” was undertaken at Department of Post Harvest Technology from 2017-2019 with the objective to evaluate the feasibility of Pusa Zero Energy Cool Chamber as a low cost on-farm storage structure for horticultural perishables during different seasons under humid tropical climate of Kerala. Six different fruits and vegetables, viz., papaya, snake gourd, cucumber, bitter gourd, amaranth and cowpea were stored in perforated plastic crates under Pusa zero energy cool chambers (PZECC) each of 165cm length, 115 cm breadth and 75 cm height during three seasons viz., June - September, October - February and March – May by maintaining 85-95% relative humidity inside the chamber with same set of commodities kept under ambient storage conditions as control. The study was conducted as six separate experiments for different commodities and possibility of storage of each commodity during different seasons was assessed based on physical, physiological, chemical and sensory quality parameters. Papaya, snake gourd and bitter gourd stored in PZECC during March- May and October- February had high shelf life, marketability and colour, where as cucumber had high shelf life and marketability when stored in PZECC only during March - May. Though the treatment combinations had no significant effect, amaranth and cowpea kept inside the PZECC had high shelf life, marketability and colour with low physiological loss in weight. The enhanced shelf life received for papaya fruits kept in ZECC was only 1.55 and 1.66 days during Oct- Feb and March- May respectively compared to their corresponding ambient storage, where as it was 0.89 and 0.66 days for bitter gourd and 0.78 and 1.55 days for cucumber. Amaranth had two days additional shelf life when kept under PZECC. Papaya, bitter gourd, cucumber and snake gourd had least shelf life when stored in PZECC during June- September. Storage under the chamber during June – September had resulted in poor colour development in bitter gourd and snake gourd, poor texture in snake gourd and lowest marketability in cucumber. All the sensory parameters were affected by the treatments in cucumber, amaranth, and cowpea. In other commodities, majority of the sensory parameters were not influenced by season and storage conditions Microbial load of papaya and snake gourd, cowpea, amaranth were not affected by the treatments; But bacterial load in bitter gourd and fungal load in cucumber were high when stored under PZECC during June – September. Carotene content in snake gourd and cowpea, vitamin C of bitter gourd, cucumber and cowpea and oxalate content in amaranth were not influenced by the treatments indicating that majority of the nutritional parameters were unaffected by storage conditions. PZECC is a low cost on-farm storage structure which could be constructed at a cost of Rs.5000/- per unit. But the structure helped only in marginal enhancement in shelf life of horticultural perishables that too only during March- May and October- February and was not at all suitable during the rainy season (June-September). The result of the present study showed that the PZECC, designed for the Rural North India as such cannot be recommended as an efficient on farm storage structure for Kerala. It has to be suitably modified for tropical humid climate and proper post harvest management practices are to be adopted before storing a commodity in the storage structure, so that it would be a better option for temporary storage of commodities awaiting marketing and short term maintenance of quality horticultural perishables, reducing the wastage of perishable commodities.ThesisItem Open Access Evaluation and utilisation of edible lichen parmotrema tinctorum (Nyl.) hale for food preservation(Department of Post Harvest Technology, College of Horticulture, Vellanikkara, 2018) Anupama, T V; KAU; Sheela, K BInvestigation on “Evaluation and utilisation of edible lichen Parmotrema tinctorum (Nyl.) Hale for food preservation” was carried out in the Department of Post Harvest Technology, College of Horticulture ,Vellanikkara during 2014-2017. The main objectives of the study were to evaluate the biochemical constituents, proximate composition, antimicrobial activity, feasibility for food preservation and to study the toxicological effect of the lichen Parmotrema tinctorum. The lichen samples were collected from Chembra, Meppadi, Moolankavu and Ambalavayal areas in Wayanad district, and they were identified as Parmotrema tinctorum by colour spot tests. The samples read K-, C+, KC+ and Pd- for the lichen Parmotrema tinctorum. The habitat of lichen was found to be the shady places of the evergreen forests at 736m -2100m above MSL. Parmotrema tinctorum is found to be corticolous (growing on the surface of trees) in habit. Thallus of the lichen is foliose, loosely attached, lobes irregular, margins entire, upper surface grey, smooth, shining; lower surface black and marginal area brown. Proximate analysis of Parmotrema tinctorum revealed a high content of total protein (15.70 %), crude fibre (14.16%), ash (10.50%) and total phenols (322 mg/100g). Parmotrema tinctorum also contained total carbohydrate (20.03 g/100g), crude fat (1.28%), ascorbic acid (4.66 mg/100g) and total free amino acids (8.25 mg/g). High content of calcium, magnesium, potassium and iron were found in the mineral analysis of Parmotrema tinctorum. Methanol, ethyl acetate and acetone extracts of Parmotrema tinctorum were analysed for antioxidant activity by DPPH and ABTS assays, and the highest scavenging action was detected in the methanol extract against the DPPH free radicals (IC50-1.47 mg/ml) and the ABTS radicals (IC50-1.27 mg/ml). Preliminary phytochemical screening of Parmotrema tinctorum revealed maximum phytochemicals in methanol extract viz. carbohydrates, phenols, flavonoids, tannins, terpenoids, fixed oils and coumarins. The TLC profiling of lichen extracts (hexane, methanol and acetone) showed maximum compounds in acetone extract, and the spots indicated the presence of phenols and terpenoids. A range of volatile compounds were observed when the lichen extracts (methanol, hexane, acetone, chloroform and ethanol) were subjected to GC-MS analysis.Volatile compounds with antimicrobial properties identified were orcinol, methyl orsellinate, atraric acid, atranorin, methyl haematommate, glyceryl trilaurate, lauric acid vinyl ester and gamma-sitosterol. In vitro testing of antimicrobial activity of acetone, ethanol and chloroform extracts of Parmotrema tinctorum using disc and well diffusion methods revealed their inhibitory action against the selected food spoilage organisms. Ethanol extract (EE) of Parmotrema tinctorum produced maximum inhibition of Aspergillus niger, while chloroform extract (CE) produced maximum inhibition of Aspergillus oryzae. The growth of both yeast species, Saccharomyces cerevisiae and Zygosaccharomyces bailii, was found to be inhibited maximum by the ethanol extract followed by the chloroform extract of the lichen Parmotrema tinctorum. In both disc diffusion and well diffusion methods, the growth of Bacillus subtilis and Staphylococcus aureus were remarkably inhibited by the acetone extract (AE) followed by chloroform extract (CE) forming zones of inhibition at all the concentrations tested. Feasibility of utilizing Parmotrema tinctorum for food preservation was evaluated by adding in powder and in ethanol extract form in two processed products viz. lime pickle and tomato sauce. In lime pickle, bacterial count was least in treatments T8 and T7 (added with 0.3% and 0.2% ethanol extracts respectively). Product preserved with 250 ppm sodium benzoate (T2) revealed least fungal count (0.6x103 CFU/g), which was on par with that containing 0.3% ethanol extract (1.0x103 CFU/g). Lowest yeast count was observed in T8, followed by T2 (0.3 x103 CFU/g). The shelf life of lime pickle treated with T2 (product preserved with 250 ppm sodium benzoate) was estimated to be six months, while that of T8 (product treated with 0.3% ethanol extract) was found to be five months. Unpasteurised tomato sauce in which 0.1% ethanol extract was added had significantly lower bacterial count (5.2X106 CFU/g). The tomato sauce preserved with 750 ppm sodium benzoate recorded lowest fungal and yeast count. The products added with 0.05% and 0.1% ethanol extract of lichen also recorded lower fungal and yeast counts. Microbial analysis of products showed the relevance of ethanol extract as an alternative to sodium benzoate in preventing the microbial spoilage of foods. Sensory analysis revealed that lichen extract added products were acceptable for consumption. Acute oral toxicity study of the ethanol extract of Parmotrema tinctorum conducted in Wistar rats revealed the absence of clinical signs of toxicity and mortalities. There were no treatment related changes in body weight and gross pathological changes in the test animals. Single dosing of ethanol extract of Parmotrema tinctorum upto a dose of 2000 mg/kg body weight orally was found to be safe in Wistar rats.ThesisItem Open Access Aloe vera based edible film coating for shelf life extension in tomato (solanum iycopersicum)(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2018) Thushara, T Chandran; KAU; Mini, CThe present investigation on “Aloe vera based edible film coating for shelf life extension in tomato (Solanum lycopersicum)” was carried out at the Department of Post Harvest Technology, College of Agriculture, Vellayani during the period of 2014-2017, with the objective to standardise an Aloe vera gel based edible film coating for tomato fruits to withstand storage and transportation losses and thereby formulate a viable and efficient post harvest management practice for extending shelf life of tomato. A preliminary trial was conducted for standardization of Aloe vera gel based edible film using four different gelling agents (INS 401, 402, 440 and 508), seven concentrations (1, 2, 5, 10, 15, 25 and 35%) and five durations (1, 2, 5,10 and 15 minutes) for extending shelf life of tomatoes. Based on the physiological loss in weight and shelf life obtained, 12 superior treatment combinations including INS 401 and 402 at 1 and 2% concentrations dipped for 1, 2 and 5 minutes were selected for further study of the experiment. Further experiments were carried out as four different steps using tomato variety Akshaya, harvested independently at two different maturity stages viz., mature green and firm ripe which were meant for distant and local market transportation respectively. Evaluation of the selected 12 aloe gel based edible films on quality parameters revealed the superiority of aloe gel based treatments over untreated fruits harvested in both the maturity stages. Shelf life of aloe gel based edible film coated mature green and firm ripe tomatoes were 36 and 24 days respectively. On the 36th day of storage all the aloe gel based treatments were equally effective in maintaining chemical and microbial quality parameters of the mature green tomato fruits, but fruits dipped in 2% aloe gel + INS 402 for two minutes recorded least PLW and percent leakage and hence had higher scores for sensory parameters. Firm ripe fruits dipped in aloe gel +INS 402 (1%) for one minute had superior physical and physiological parameters on 24th day of storage. The possibility of increasing the efficiency of aloe gel based formulation by incorporation of natural and cheap plant leaf extracts from papaya, guava and ocimum in 1:1 and 1:2 ratios for shelf life extension in tomato was assessed. Considering the economics and efficiency in maintaining better physiological quality parameters, 2% papaya leaf incorporated aloe gel (1:2) + INS 402 for two minutes was selected as the best plant leaf extract incorporated aloe gel (PLEAG) treatment for mature green fruits and 1% papaya leaf incorporated aloe gel (1:2) + INS 402 for one minute for firm ripe tomatoes. Quality evaluation of edible coatings revealed better efficiency of papaya leaf incorporated aloe gel (1:2) in reducing the activity of texture affecting enzymes viz., pectin methyl esterase and polygalactouronase and increasing total pectin content resulting in higher fruit firmness in both mature green and firm ripe tomatoes. Even though no antimicrobial activity against Erwinia and Rhizopus was noticed when tested under in vitro condition, the aloe based extracts had suppressed the post harvest infection by these pathogens in vivo. Efficiency of the selected papaya leaf incorporated aloe gel (1:2) in reducing post harvest loss during storage and transportation was compared with that of a commercial wax formulation independently for mature green and firm ripe tomato fruits after packaging in 5% ventilated corrugated fiber board (CFB) boxes with and without moulded tray. When packaged fruits were stored under optimum low temperature (12- 200C for mature green and 10-150C for firm ripe) and ambient temperature (28-300), low temperature storage was superior in maintaining the quality parameters for both the maturity stages of tomato. Packaging in 5% ventilated CFB boxes with moulded tray was effective in maintaining the physical and physiological parameters of mature green tomato during storage. Papaya leaf incorporated aloe gel (1:2) was equally effective as the commercial bee wax formulation in maintaining the physiological, chemical, and microbial parameters. Fruits coated with commercial bee wax had reduced lycopene content and a non- uniform fruit colour development and hence recorded poor sensory scores. Though both the packaging systems were equally effective in maintaining all the quality parameters during storage of firm ripe tomatoes, overall acceptability was higher for fruits kept in 5 % ventilated CFB box with molded trays. Papaya leaf incorporated aloe gel (1:2) was equally effective as the commercial wax formulation for the stored firm ripe tomatoes too. Studies to analyze the efficiency of aloe gel based coatings to withstand transportation losses revealed the superiority of 5% ventilated CFB box with moulded tray and effectiveness of papaya leaf extract incorporated aloe gel (1:2) in maintaining all the quality parameters in fruits of both maturity stages. Cost of production for coating the standardized papaya leaf incorporated aloe gel was Rs. 45.87/- for 100 Kg mature green tomatoes and Rs.23.65/- for 100 Kg firm ripe tomatoes. Based on the study, an efficient postharvest management practice for shelf life extension in tomato fruits of both maturity stages could be formulated. Mature green tomato fruits cv. Akshaya after washing and surface sanitization using 2ppm ozonized water for five minutes followed by coating with papaya leaf incorporated aloe gel (1:2) + INS 402, (2%) for two minutes, air drying and packaging in 5% ventilated CFB boxes with moulded tray had a storage life of 60 days under optimum low temperature (12-200C) or could be transported to distant markets without transportation hazards. Firm ripe tomato fruits cv. Akshaya could be stored for 36 days using the same protocol except coating with papaya leaf incorporated aloe gel (1:2) + INS 402, (1%) for one minute and storing at an optimum low temperature of 10-150C or could be transported to local markets without any hazards.ThesisItem Open Access Portion packaging and storage of jackfruit (Artocarpus heterophyllus Lam.)(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2018) Gana, K R; KAU; Mini, CThe investigation entitled “Portion packaging and storage of jackfruit (Artocarpus heterophyllus Lam.)” was conducted at the Department of Post Harvest Technology, College of Agriculture, Vellayani, during the year 2016-2018, with the objective to standardize portion packaging and storage techniques for extending shelf life of jackfruit types. Experiment was carried out independently for mature varikka, ripe varikka and mature koozha jack fruit types. Good quality jackfruit types were harvested, cleaned, outer spiny rind removed, cut in to portions of 200-250 g weight, pre-treated using 0.5% potassium meta bisulphite (KMS) and citric acid, surface drained and subjected to seven different packaging conditions, and stored under ambient and refrigerated storage conditions. The seven different packaging systems included use of polypropylene film with 5% ventilation, cling film wrapping, shrink wrapping, vacuum packaging in laminated pouches, modified atmospheric packaging (MAP) in laminated pouches with KMnO4, MAP with silica gel and unwrapped portions. Based on efficiency in maintaining physiological parameters, organoletic quality and marketability, portions under vacuum packaging in laminated pouches of PP/LDPE under refrigeration was selected as best treatment for further quality evaluation. MAP in laminated pouches with silica gel sachet was considered as the second best packaging treatment. Jackfruit portions stored under ambient condition were spoilt within a day in all types. Quality evaluation of jackfruit portions stored under refrigeration after vacuum packaging in laminated pouches of PP/LDPE revealed that mature varikka portions had 21 days shelf life with 2.34% physiological loss in weight and 80% marketability. Vacuum packed mature koozha portions under refrigeration exhibited 15.71 days shelf life with 2.89% PLW and 75% marketability. Ripe varikka portions had 12.28 days shelf life with 3.42% PLW and 70% marketability under similar packaging and storage. Unwrapped jack fruit portions under refrigeration were spoilt within 3 days after storage. Oxygen concentration gradually decreased and CO2 concentration gradually increased in all the vacuum packaged jackfruit portions, indicating high respiration rate of the fresh cut commodity. TSS, reducing sugars and total sugars increased during storage, where as vitamin C and acidity showed a decrease during storage. Vacuum packed refrigerated jackfruit portions had good sensory acceptability even at the end of shelf life, though there was reduction in firmness. Despite an increase in the carotenoid content, vacuum packed refrigerated jack fruit bulbs retained their natural colour, which stayed even during the storage period. The mature varikka bulbs held a cream colour while the ripe varikka ones were a deep yellow, and the mature koozha bulbs remained yellow even at the end of storage. Cost of production of vacuum packed jack fruit portion was calculated and the BC ratio was found to be 1.37. Vacuum packaging in laminated pouches of PP/LDPE and storage under refrigeration was standardized as the best packaging and storage treatment for all jack fruit portions. Adoption of the standardized technology may help to transform the current trend of total unhygienic marketing system into a totally different style, where hygienically packed quality jackfruit portions with sufficient prolonged shelf life can be marketed through the current retail outlets having refrigerated storage facility. The system has to be properly modified in future to suit the ambient storage system so as to reduce the cost of production.ThesisItem Open Access Postharvest treatments for delayed ripening in nendran banana (Musa spp.)(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2018) Athira, M Nair; KAU; Geetha Lekshmi, P RThe investigation entitled “Postharvest treatments for delayed ripening in Nendran banana (Musa spp.)” was conducted at the Department of Post Harvest Technology, College of Agriculture, Vellayani, during 2016-2018. The objective of the programme was to study the effect of postharvest application of different ethylene inhibitors and to standardize the optimum concentration for delayed ripening and extended shelf life of Nendran banana. Nendran banana bunches of uniform maturity were selected from Instructional Farm, College of Agriculture, Vellayani. De-handed banana fruits were treated with different ethylene inhibitors at various concentration viz. Benzyl Adenine (BA) (30 ppm, 50 ppm, 80 ppm - dipping for 10 minutes), Hexanal (0.5%, 1.0%, 1.5% - dipping for 10 minutes), Nitric Oxide (NO) (0.25 mM, 0.5 mM, 0.75 mM - dipping for 5 minutes), Salicylic Acid (SA) (1 mM, 1.5 mM, 2 mM - dipping for 10 minutes) along with distilled water, ethanol and absolute control (without any treatment). Treated banana fruits were air dried and stored under room temperature (30+20C, RH 80-85%) in Corrugated Fiber Board boxes till the end of shelf life. Effectiveness of different ethylene inhibitors for delayed ripening of Nendran banana was evaluated by analyzing physiological, biochemical, physical and sensory qualities. Nendran banana fruits treated with 50 ppm BA recorded a pulp percentage of 69.38%, peel percentage of 30.62% and pulp to peel ratio of 2.26 with the lowest physiological loss in weight (PLW) (13.01%) and respiration rate (97.55 mL CO2 kg-1 h-1) after 15 days of storage. Total sugar (20.82%), reducing sugar (17.55%), TSS (24.25 0B) and acidity (0.45%) increased with storage and highest retention of vitamin C (10.74 mg 100g-1) content and antioxidant activity (78.46%) were also observed at the end of storage. When fruit firmness, colour and sensory parameters were analyzed, BA 50 ppm treated banana fruits exhibited maximum fruit firmness of 10.55 N after 15 days of storage with optimum ripening (Stage VI). It also exhibited maximum mean score for sensory parameters viz. appearance, colour, flavour, taste, texture and overall acceptability and recorded a shelf life of 16.75 days. Nendran banana fruits treated with SA (2 mM) recorded a shelf life of 15.75 days next to BA (50 ppm) with 13.82 % PLW and respiration rate of 106.23 mL CO2 kg-1 h-1. When biochemical parameters were analyzed, SA 2 mM recorded a total sugar content of 21.50%, reducing sugar (18.05%), TSS (25.45 0B), acidity (0.48%), carotenoid (0.30 mg 100g-1), ascorbic acid content (9.84 mg 100g-1) and antioxidant activity (76.55%) after 15 days of storage with good fruit firmness, colour and sensory qualities. Nendran banana fruits without any postharvest treatment (absolute control) had a shelf life of 11.58 days with higher rate of physiological, biochemical and physical changes. They also exhibited the highest PLW of 19.94% and high rate of respiration (128.11 mL kg-1 h-1) which lead to short shelf life and lowest mean score for sensory attributes after 12 days of storage. Application of ethylene inhibitors as postharvest treatments reduced the rate of physiological activities and extended the shelf life of Nendran banana. Based on physiological, biochemical, physical and sensory analysis, dipping of Nendran banana hands in 50 ppm Benzyl Adenine for 10 minutes was standardized as the best postharvest treatment for delayed ripening and extended shelf life up to 16.75 days whereas Nendran banana without any treatment (absolute control) recorded a shelf life of 11.58 days under room temperature storage. Dipping of Nendran banana in 2 mM Salicylic Acid for 10 minutes recorded a shelf life of 15.75 days and was found cost effective as compared to BA (50 ppm).