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ThesisItem Open Access Protocol development for minimally processed jackfruit (Artocarpus heterophyllus L.) bulbs(Department of Post Harvest Technology, College of Agriculture,vellayani, 2020) Gayathri, G S.; KAU; Mini, CThe study entitled “Protocol development for minimally processed jackfruit (Artocarpus heterophyllus L.) bulbs” was carried out in Department of Post-Harvest Technology, College of Agriculture, Vellayani with the objective to standardize an efficient and economic protocol for development of minimally processed jackfruit bulbs with extended shelf life. The work was carried out as four different continuous experiments, viz., evaluation of sanitizing agents, evaluation of pre-storage treatments, development of packaging system and assessment of acceptability. Fresh, good quality optimum mature fruits of the jackfruit cultivar Muttom varikka were harvested, allowed to ripe and were subjected to four different sanitization treatments viz., immersion in water (400C), 100 ppm sodium hypochlorite solution, 120 ppm sodium hypochlorite solution and 2 ppm ozonized water for 15 minutes each. Untreated fruits were kept as absolute control to evaluate the efficacy of sanitization treatments in controlling total microbial load on the fruit surface. All the sanitization treatments resulted in reduction in microbial load on the fruit surface. Sodium hypochlorite at both concentrations, 120 and 100 ppm, were equally effective in reducing both the bacterial and fungal load. Untreated fruits had the maximum microbial count, which was comparable with the fruits treated with water at 400C. Considering the efficiency and economics, the lower concentration of sodium hypochlorite, 100 ppm, was selected as the best surface sanitizing treatment and used for the second part of the experiment. In the second part of the study, after surface sanitization of the fruits with 100 ppm sodium hypochlorite solution, bulbs were extracted and after removal of the seeds, dipped in three different pre-treatment solutions viz, 0.1% ascorbic acid, 0.1% citric acid, 1% calcium chloride for 10 minutes. Untreated bulbs were kept as absolute control and both treated and untreated bulbs were stored under refrigerated conditions in aluminium foil trays wrapped with cling film to analyse the efficacy of pre-storage treatment solutions. All the pre-storage treatments resulted in better physiological, chemical and sensory quality parameters of the bulbs compared to the untreated ones. However, all the bulbs except the ones treated with 1% calcium chloride solution had to be discarded by 5th day of storage owing to deterioration. Pre-storage treatment of the bulbs with calcium chloride (1%) resulted in maximum shelf life (5.00 days), TSS (20.200B), ascorbic acid (23.69) and total carotenoid content (0.83), lowest physiological loss in weight (2.03), percent leakage (79.24), acidity (0.36%) and total phenol content (39.77), after three days of storage, with best sensory scores and hence selected as the best pre-treatment for minimally processed jackfruit bulbs. In the third part of the study, fruits and bulbs that received the best treatments mentioned above were kept under four different packaging systems viz., laminated pouch, shrink wrapping, cling film wrapping and aluminium tray wrapped with cling film were compared under refrigerated (5-70C) conditions. Jackfruit bulbs packaged in laminated pouches recorded the maximum shelf life (7 days), TSS (18.920B), total sugar (37.28%), reducing sugar (16.75%), non-reducing sugar (20.53%), vitamin C (27.43 mg100g-1), total carotenoid (0.83) content with maximum sensory scores. They also had least PLW (1.17), percent leakage (65.90), acidity (0.31%) and phenol content (39.50). Shrink wrapping was the second best in maintaining quality with 6 days shelf life, and bulbs wrapped in cling film showed the least quality parameters with a shelf life of 4 days only. All jackfruit bulbs except those packed in laminated pouch and shrink wrap were found to be spoiled and had to be discarded by 6th day of storage. Minimally processed ripe jackfruit bulbs of cv. Muttom varikka can have a shelf life of seven days if surface sanitization of fruit are done using 100 ppm sodium hypochlorite for 15 minutes, followed by pretreating de-seeded bulbs with 1% calcium chloride for 10 minutes and stored under refrigerated conditions after packaging in laminated pouch of PP/LDPE. Minimally processed jackfruit bulbs prepared as per the standardized technology above had acceptable sensory scores for appearance (7.10), colour (6.96), texture (7.26), taste (6.90), flavour (6.60) and overall acceptability (7.43) even at the end of shelf life period. Cost of production of 1 kg minimally processed jackfruit bulbs was estimated to be Rs. 206.89/-.ThesisItem Open Access Post harvest management practices in pineapple (Ananas comosus (L.) Merr.)(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2020) Elso Remya, Rajan.; KAU; Mini, CThe experiment entitled “Postharvest management practices in pineapple (Ananas comosus (L.) Merr.)” was conducted at the Department of Post Harvest Technology, College of Agriculture, Vellayani, during the year 2018-2020, with the objective to standardize the post-harvest management practices in pineapple for improved fruit quality. The experiment was conducted separately for two maturity stages viz., stage1 (0- 25% eyes predominantly yellow) and stage 2 (25-50% eyes predominantly yellow) meant for distant and local markets respectively. The study was conducted as two continuous experiments. In the first part, harvested pineapple fruits were subjected to four different pre-treatments viz., dipping in hot water of 50±20C for 1 minute, hydro cooling for 5 minutes, sanitization with 30 ppm sodium hypochlorite solution for 10 minutes and ozonisation with 2 ppm ozone for 15 minutes. The treated fruits along with untreated fruits were evaluated for the effects of pre-treatments on shelf life, physiological loss in weight and microbial load of pineapple fruits for selection of the best pre-treatment. All the pre-treatments resulted in enhanced shelf life, reduced physiological loss in weight and low microbial load on pineapple fruit surface. Pineapple fruits of stage1 and stage 2 maturity, when subjected to hot water dip at 50±20C for one minute had maximum mean shelf life of 15.2 and 12.6 days respectively, with least physiological loss in weight and microbial count. Sanitization using 30 ppm sodium hypochlorite solution for 10 minutes was equally effective as hot water dip at 50±20C, whereas ozonization was effective as hot water treatment in stage 2 pineapple alone. Based on efficiency and economics in maintaining the extended shelf life with least PLW and microbial load, hot water dip at 50± 20C for one minute was selected as the best pre-treatment for both maturity stages and was selected for the second part of the experiment. In the second part of the experiment, harvested pineapple fruits of two maturity stages were independently subjected to hot water dip at 50± 20C for one minute and stored under low (240C) and ambient (320C) temperature conditions along with untreated fruits and the stored fruits were subjected to evaluation of physiological, chemical and sensory quality parameters. Untreated pineapple fruits of stage 1 maturity stored under ambient temperature had least shelf life (12 days), highest physiological loss in weight (12.29 %) and had to be discarded after 12 days due to spoilage. Fruits treated with hot water and stored under low temperature conditions had maximum shelf life (21.25 days), least PLW (4.53%), minimum TSS (14.26 °B), total sugar (10.45%) and reducing sugar (4.36%), highest acidity (0.91%), non-reducing sugar (6.09%) and vitamin C (22.85%) after 12 days of storage. In case of fruits of stage 2 maturity, untreated pineapple fruits stored under ambient temperature had least shelf life (10.5 days) and highest physiological loss in weight (8.40%). Fruits treated with hot water and stored under low temperature had maximum shelf life (18.25 days), least PLW (2.48%), minimum TSS (15.78°B), total sugar (11.15%) and reducing sugar (4.13%), highest acidity (0.81%), non-reducing sugar (7.02%) and vitamin C (22.91%) after 9 days of storage. All the treatments were effective in maintaining high sensory quality parameters viz., appearance, flavour, texture, taste, flesh colour and over all acceptability, of which hot water dip treatment followed by low temperature storage had the highest mean score while untreated fruits stored under ambient temperature recorded the lowest scores in both maturity stages. In general, fruits treated with hot water when stored under low temperature conditions had better physiological and chemical quality parameters and the same were reflected in acceptability scores of the commodities. Hot water treatment alone gave better quality pineapple fruits compared to untreated ones, and a combination of hot water treatment and low temperature storage further improved the quality and shelf life of fruits of both maturity. It can be concluded that pineapple fruits (var. Mauritius) harvested with crown and two cm stalk at stage1 maturity when subjected to hot water treatment at 50±20C for 1 minute followed by low temperature storage (240C) could extend the shelf life of pineapple meant for distant markets up to 21.25 days. Same management practice resulted in extension of shelf life to18.25 days for stage 2 maturity stage pineapple fruits meant for the local market.ThesisItem Open Access Product development from tender cashew nut(Department of post harvest Technology ,College of Horticulture, Vellanikkara, 2020) Sharon, Jacob; KAU; Sobhana, ACashew, an important horticultural crop of India, has great socioeconomic significance in our country. Cashew seed is often considered a nut in the culinary sense and this nut is either eaten on its own or used in different recipes of food preparation. Substantial quantities of cashew nuts are produced during rainy season in Kerala, especially in the late season flowering types, which are inferior in quality and are being wasted. To avoid this loss, harvesting could be carried out in the immature stage and could make value added products. Hence, the present research work was carried out to study the utilisation of immature cashew kernels, its storage methods and potential of value addition. Six different varieties viz., Madakkathara-2, Sulabha, Dhana, Priyanka, Poornima and Kanaka were selected to study the physical and biochemical parameters of the immature cashew kernels. Among the physical characteristics, shelling percentage was highest for Madakkathara-2 (17.88%), the highest kernel weight was for Poornima (2.76g) and the highest kernel size, shell weight and testa weight was observed for the variety Priyanka. Other physical parameters like colour, external appearance and shape of kernel differed with varieties. The estimated range of composition of immature cashew kernels was 0.19-0.23% tannins, 4.88-9.63% carbohydrates, 5.08-9.08% fat and 7.29- 12.45% protein, which varied with varieties. Storage studies of immature kernel were carried out by preserving in different concentrations of brine solution (5%, 10% and 15%), sugar syrup (50°B, 60°B and 70°B) and after drying (2-3% moisture content). Storage period was for four months and the best storage method was preserving in 10% brine and 70°B sugar syrup, which had high organoleptic scoring and acceptable limit of microbial count. Pre-treatments like washing and steam blanching could reduce the tannin content in kernels. Various value added products were prepared from the stored kernels viz., salted bits and pickle from kernels preserved in brine; dried bits and preserve from kernels preserved in sugar syrup; and cashew ball, cookies, jaggery coated cashew bits and honey coated cashew bits from kernels preserved after drying. Most of the value added products showed high acceptability during organoleptic evaluation and was comparable with those from fresh kernels. Even some of the products like honey coated and jaggery coated cashew bits showed higher acceptability than those from fresh kernels. The immature cashew kernels are potential raw materials for preparing value added products especially during rainy season to avoid the loss of matured nuts. Also these kernels were observed to contain enough nutrients which makes it a healthy food item.ThesisItem Open Access Post harvest management practices in mango(Mangifera indica L.)(Department of Post Harvest Technology, College of Agriculture, Vellanikkara, 2020) Harya Krishna, V; KAU; Meagle Joseph, PMango (Mangifera indica L.), the king of fruits, relished by majority, occupies first position in production in India and world. The problems featured in the journey of the fruits from field to market are numerous. Burondkar et al. (2018) estimated that about 20 - 30 per cent of harvested mango fruits became sub-standard due to rough handling, pathogenic infestations, improper packaging, unhygienic storage and indecorous mode of transportation. This shows the necessity of improving post harvest management practices to enhance shelf life without deteriorating its quality. The investigation on the “Post harvest management practices in mango (Mangifera indica L.)” was carried out at the Department of Post Harvest Technology, College of Horticulture, Vellanikkara, Thrissur, Kerala during 2018-2020. The objectives were to standardise post harvest and ripening treatments for important commercial mango varieties of Muthalamada, Palakkad, from where the mango fruits reach Indian markets in early season. The effect of different post harvest treatments on mango fruits during storage were studied in four mango varieties such as Alphonso, Bennet Alphonso, Banganapalli and Bangalora. The physical and biochemical changes of treated fruits, stored under both ambient and cold storage conditions were studied. The postharvest treatments given were hot water dip, hydro cooling, sanitization with sodium hypo chlorite solution, ozonisation, waxing and dipping in sodium bicarbonate solution. Among the different treatments, 1 per cent Nipro fresh (carnauba wax) coated fruits stored under cold storage at 12±20C recorded good quality attributes in both Alphonso and Bangalora varieties. Coated fruits of Alphonso maintained quality evidenced by reduction in PLW (6.52 %), delayed colour change (16 days), firmness (0.09 N), acidity (0.21%), ascorbic acid (49.50mg/ 100g), total carotenoid (7.80mg/100g), total sugar (13.90 %), non reducing sugar (12.10 %) and TSS (170 brix) even after a storage period of 23 days. Fruits of Bangalora coated with wax had extended the shelf life up to 26.50 days against control fruits (17.50days) with lowest PLW (7.80 %), delayed colour change (26 days), acidity (0.10%), firmness (0.32 N ), ascorbic acid (9.95 mg/100g), total sugar (7.86%) and a TSS of 110 brix. In Bennet Alphonso, dip in sodium hypochlorite solution (100ppm) for five minutes was suitable for getting a lowest PLW (9.63 %), firmness (0.07 N), acidity (0.17 %), higher TSS (18.50 brix), ascorbic acid (23.32 mg/ 100g), total sugar (12.60 %), reducing sugar (3.18 %), total carotenoid (6 mg/ 100g) and a storage period of 28.50 days. In Banganapalli, the fruits treated with ozone were good in quality attributes like TSS (18.200 brix), total sugar (15.20 %), non reducing sugar (8.84 %), ascorbic acid (6.76 mg/ 100g), delayed colour change (15 days), firmness (0.28 N), acidity (0.13 %), total carotenoid (1.72 mg/ 100g) and PLW of 14.10 per cent with a storage life of 23 days in cold storage. Standardization of ripening techniques was done in the variety Bennet Alphonso at their full mature stage. The fruits were subjected to different ripening treatments and kept for storage under ambient condition. Among various treatments, ethrel (200 ppm) sprayed fruits induced uniform ripening within four days followed by hot water dipped (50±20C, for one minute) fruits which ripened in five days as against eight days in control. Spraying ethrel (200 ppm) had a longer keeping quality of 11 days with good quality attributes like TSS (18.170brix), total carotenoids (16.10mg/100g), ascorbic acid (12.86), firmness (0.20 N), total sugar (12.56%) and a highest score (7.20) in overall acceptability in sensory evaluation. Hot water treated fruits were fully ripened in five days and exhibited longer keeping time of 12 days with good quality parameters like TSS (150brix), acidity (0.37%), total carotenoids (33.98mg/100g), ascorbic acid (22.50mg/100g), firmness (0.49 N), total sugar (11.19%) and non reducing sugar (7.12%) with a score of 6.55 in overall acceptability in sensory evaluation.ThesisItem Open Access Postharvest quality management of papaya (Carica papaya L.)cv. red lady(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2020) Menaka, M; KAU; Geetha Lekshmi, P RThe present study entitled ―Postharvest quality management of papaya (Carica papaya L.) cv. Red Lady‖ was conducted at the Department of Post Harvest Technology, College of Agriculture, Vellayani, Thiruvananthapuram during the year 2018-2020. The objective of the experiment was to standardize postharvest treatments for delayed ripening and to extend the shelf life of papaya cv. Red Lady with minimum nutritional loss through postharvest handling practices. Papaya fruits (cv. Red Lady) of uniform size, shape and maturity at colour break stage were procured from the field of progressive farmers of Farmer Producer Organisation, at Pallichal, Thiruvananthapuram. Harvested fruits were sanitized (ozonisaton 2 ppm) and subjected to hot water treatment (500C for 20 minutes) followed by postharvest dipping of fruits for 5 minutes using different treatments viz., Naphthalene Acetic Acid (NAA 250 ppm), Edible coating (Papaya Leaf Extract Aloe Gel), Gibberellic Acid (GA3 100 ppm), Calcium chloride (CaCl2 2%), Salicylic Acid (SA 2 mM), hot water treatment alone and fruits without any postharvest treatment as absolute control. Treated fruits, after removal of surface moisture, were stored in corrugated fibre board boxes at room temperature (30±2 ⁰C, RH 80-85%) till the end of shelf life. Superiority of postharvest treatments on papaya cv. Red Lady was assessed based on physiological, biochemical, physical, and sensory attributes during storage at an interval of 3 days. Papaya fruits treated with Salicylic Acid (2 mM) recorded the lowest percentage of physiological loss in weight (6.55%), and respiration rate (74.99 mL CO2 kg-1 h-1) after 9th day of storage where as fruits without any postharvest treatment recorded a weight loss of 16.65% with a respiration rate of 101.92 mL CO2 kg-1 h-1. Fruits with salicylic acid treatment recorded 8.72% total sugars, 6.39% reducing sugars, 7.66 ˚Brix of total soluble solids with a carotenoid content of 2.09 mg 100g-1, and antioxidant activity of 48.35% after 9 days of storage which increased with the storage period and the values were significantly lower than the untreated fruits indicating the delayed ripening of treated fruits. Red Lady papaya fruits without any postharvest treatment (control) recorded the lowest storage life of 7.38 days due 147 to high rate of physiological, biochemical and physical changes which indicated faster ripening and senescence. The treatment of fruits with salicylic acid (SA) recorded the lowest respiration rate of 95.63 mL CO2 kg-1 h-1 and physiological loss in weight (13.10%) after 14 days of storage at room temperature with the highest fruit firmness (19.89 N) and 8.26% reducing sugar, 12.73% total sugar, 11.52 ˚Brix of total soluble solids, 0.14% titratable acidity, 2.55 mg 100g-1 of carotenoid content, and 64.53% of antioxidant activity. The salicylic acid treatment recorded the highest shelf life of 14.56 days with acceptable sensory parameters where as fruits without any treatment (control) recorded a shelf life of 7.38 days. Papaya fruits cv. Red Lady, harvested at colour break stage were sanitized using ozonation (2 ppm) and subjected to hot water treatment (50 ˚C for 20 minutes) followed by dipping for 5 minutes in postharvest treatment with salicylic acid at 2 mM was standardised as the best postharvest treatment for delayed ripening which recorded the longest shelf life of 14.56 days at room temperature as compared to 7.38 days for fruits without any postharvest treatment.ThesisItem Open Access Postharvest quality management in banana CV nendran (Musa spp.)(Department of Post Harvest Technology, College of Agriculture, Vellayani, 2020) Aparna Nath, S S; KAU; Geetha Lekshmi, P RThe study entitled “Postharvest quality management in banana cv. Nendran (Musa spp.)” was conducted in the Department of Post Harvest Technology, College of Agriculture, Vellayani, Thiruvananthapuram during the year 2018-2020. The objective of the experiment was to standardize the postharvest management for delayed ripening and extended shelf life of banana cv. Nendran with minimum nutritional loss through postharvest handling practices. Good quality banana fruits (cv. Nendran) of uniform size and maturity, procured from progressive farmers of Farmer Producer Organization, Kalliyoor, Thiruvananthapuram were used for the study. The fruits were de-handed and sanitized with ozonation at 2ppm. The sanitized fruits were subjected to different postharvest treatments viz., Calcium chloride (CaCl2 4%), Gibberellic Acid (GA3 150 ppm), Oxalic Acid (OA 20 mM), Salicylic acid (SA 2 mM) as against fruits without any treatment as control. The treated fruits after the removal of excess moisture were stored in Corrugated Fibre Board boxes under room temperature conditions (30 ± 2 0C, RH 85- 90 %). Effectiveness of the treatments was analysed based on physiological, biochemical, physical and sensory parameters at an interval of 3 days till the end of shelf life. After 15 days of storage, Nendran banana fruits treated with Salicylic Acid (SA 2 mM) recorded the least Physiological Loss in Weight (PLW) of 13.43 % and respiration rate of 102.70 mL CO2 kg-1h-1 with a pulp percentage of 70.61 %, 29.39 % peel percentage and pulp to peel ratio of 2.40 with a fruit firmness of 10.13 N. The stored fruits also recorded an increase in the moisture content (61.27 %), Total Soluble Solids (24.60 o Brix), reducing sugar (17.34 %), total sugar (20.21 %), and acidity (0.45 %) with 10.19 % of starch content, 75.52%antioxidant activity and 9.30 mg 100g-1 ascorbic acid content after 15 days of storage. The fruits had acceptable sensory attributes viz., appearance, colour, flavor, taste, texture and overall acceptability and resulted in a shelf life of 15.67 days. 139 Nendran banana fruits treated with Gibberellic Acid (GA3 150 ppm) recorded a shelf life of 14.3 days next to SA (2 mM) with a respiration rate of 112.38 mL CO2 kg- 1h-1, Physiological Loss in Weight of 14.3 %, pulp percentage of 73.32 %, 26.68 % peel, pulp to peel ratio as 2.75, 17.80 % reducing sugar, 21.05 % total sugar, 74.31% antioxidant activity, and 8.59 mg 100g-1ascorbic acid content after 15 days of storage. The untreated Nendran banana fruits recorded a shelf life of 11.13 days with the highest rate of physiological, biochemical, and physical changes and the lowest mean scores for organoleptic qualities. Application of postharvest treatments significantly reduced the rate of physiological activities which contributed to the delay in ripening and extension of shelf life of Nendran banana. Nendran banana fruits harvested at uniform maturity, sanitized with ozonation (2 ppm) and subjected to postharvest treatment with salicylic acid (2 mM) for 10 minutes as dipping was standardized as the best postharvest treatment based on physiological, biochemical, physical and sensory analysis which recorded a shelf life of 15.67 days under room temperature storage as against 11.13 days in fruits without any postharvest treatments.