"Studies on the development and shelf life of litchi juice concentrate* Ranote PS , ShelkeA, BhartiThe litchi (Litchi chinensis sonn) is a subtropical fruit and is always held in high esteem dueto its deliciously flavoured sweet, juicy aril. It seems to have cultivated since 1500 BC in China by thepeople of Malayan descent before the Chinese had moved that far south (Chandler 1958). Litchi ranksnext to citrus and avocado in importance in subtropics (Ochse et al 1961). The litchi fruit contains fairamount of protein, fat, minerals and vitamins (A, B and C). It contains protein (0.8-0.95 percent), fat(0.3 percent), pectin (0.42 percent) and minerals specially calcium, phosphorus and iron (0.7 percent)as observed by Wenkan and Moller (1965) and Fong (1966). At national level, area under litchi was56.4 thousand hectares with total production of 433.2 thousand metric tonnes (Anonymous 2001). Theaverage productivity in the country is reported to be 7.6 tonnes per hectare. It occupies the share of1.4 percent and 0.9 percent in total area and production, respectively (Kumar et al 2001). Shahi, Rosescented, Early seedless late, Early large red, Calcuttia, Dehradun, Seedless late, Muzaffarpur,Saharnpur are some of the popular varieties of litchi. Litchi is mostly liked as a table fruit as it is very delicious, juicy and refreshing. Thoughmajor part of the litchi produced is marketed as fresh fruit. However, litchi can be utilized forpreservation and processing into different products such as canned litchi, squash, cordial, syrups,ready to serve drinks, jam, jelly, juice, concentrates and it can also be dehydrated to get a very popularproduct “litchi nut” as called in China. In addition, litchi juice can also be fermented to produce wine.Since litchi fruit mature in hot season, the fruit deteriorate rapidly after harvest due to pericarpbrowning i.e. loss of red colour and fruit decay. The postharvest life of litchi fruit at ambienttemperature is less than 3 days. This short postharvest period limits its long-distance transportation,marketing and consumption. Therefore postharvest research becomes a key problem in thedevelopment of litchi production (Lin et al 2003). Low temperature storage, sulphur dioxide fumigation, dipping in wax emulsions etc. are usedto extend the shelf life of litchi fruit in commercial situations. However, there is increasing consumerand regulatory resistance to the use of chemicals (Jiang et al 2003). So, the concentration of fruitjuices to thick viscous liquid or powders for subsequent reconstitution as fruit juice or for use inpreparation of beverages, baked products, frozen dairy products and jellies etc. has attracted muchattention. The juice concentration permits the economy in packing, transportation, storage and and thereadiness with which they can be used are responsible for the early interest in fruit juice concentrates. Materials and methodsTwo varieties of litchi viz. Dehradun and Seedless late were procured from the Regional FruitResearch Station, Gangian (Distt. Hoshiarpur) and processed at the pilot-plant of the Department ofFood Science and Technology, Punjab Agricultural University, Ludhiana, Punjab. The defective andinjured fruits were sorted out and fully mature and healthy fruits were retained for processing. Thefruits were peeled and destoned manually. The juice was extracted with the help of screw type juiceextractor with subsequent filtration through muslin cloth. The filtered juice was divided into two lots.One lot of freshly extracted juice was subjected to concentration while the other one was preservedwith 2000ppm potassium metabisulphite in glass bottles for later on concentration.Litchi juice concentrate was prepared from freshly extracted juice, as well as chemicallypreserved juice with the help of laboratory scale single effect single stage, batch type vacuum glasso evaporator. The concentration was done at 50-55 C temperature and a vacuum of 27-30 inches ofo mercury. Final concentration of juice was maintained at 80 Brix in all the cases. Product was packedo in pearl pet jars and was stored at ambient room temperature (12-38 C) and low temperature i.e.o refrigeration (0-4 C) for a period of 6 months for periodic evaluation of quality and physico-chemicalchanges during storage. Stored product was analyzed at 0, 2, 4 and 6 months interval for variousphysico-chemical changes occurring during storage like TSS, pH, acidity, ascorbic acid, sugars,browning, pectin, viscosity, tannins and sensory quality.Physical characteristics: Flow characteristics of litchi juice concentrates were determinedusing Rheostat 2 viscometer (VEB MLW Prufgerate-werk, Medingen, Germany) with coaxial-1 cylinder attachment. The torque data were obtained at shear rates between 0.6 and 145.8 s using Hsystem (bob to cup ratio of 0.81). A measured amount of concentrates (17ml) was introduced into thecup as slowly as possible. The samples were maintained at rest for 15 minutes to equilibrate to theo experimental temperatures of 20, 30, 40 and 50 C before measurements. Temperatures of theconcentrates were controlled with a thermostatic-circulating water bath. Shear stress data wererecorded first in the ascending order, followed by a rest of 5 minutes and then in the descending order.n The values for flow behaviour index “n” (dimensionless) and consistency index “K” (Pa.s ) wereobtained from plots of log shear stress versus log shear rate as slope and intercept.The stored samples of concentrate were evaluated for sensory quality on the basis of colour,flavour, taste, body and overall acceptability by semi-trained panel of judges using 9-point Hedonicscale (Amerine et al 1965) to find out the acceptability of the product. The samples of juiceconcentrate were reconstituted to original strength and chilled before sensory evaluation.Chemical characteristics: TSS contents were determined using a hand refractometer (Erma,o o Japan) with solid scale in the range 0-50 and 40-90 percent. The TSS were expressed as Brix at 20 C using reference tables. Total solids were calculated by subtracting the moisture percent from 100 andexpressed as percent total solids. Moisture content (AOAC 1985), pH (AOAC 1985), titrable acidity(AOAC 1985), sugars (AOAC 1985), reducing sugars (AOAC 1985), total sugars (AOAC 1985),ascorbic acid (AOAC 1985), tannins (AOAC 1985) and browning (Ranganna 1994) were determined.Statistical analysis: The data of fresh and preserved samples of two varieties evaluated at 0, 24, 6 months interval was analyzed with the help of factorial design in CRD (Cochran and Cox 1957)to find out the effect of varieties, treatments, storage temperature and storage period on the overallacceptability of the stored product.Results and discussionPhysical characteristics of litchi fruit: The data regarding percentage of different components viz.peel, pulp and seed on prepared fruit basis are given in Table 1. The peel percentage, pulp percentage,seed percentage and juice recovery of Seedless late variety was 18.0, 76.0, 4.0 and 62.5 percent,respectively where as for Dehradun variety, it was 14.0, 66.5, 16.5 and 47.5 per cent, respectively.Physico-chemical composition of litchi juice: The physico-chemical composition of juice of two litchio varieties viz. Seedless late and Dehradun are presented in Table 2. Moisture (%), TSS ( Brix), Acidity(%), pH, Ascorbic acid (mg/100gm), Reducing sugars (%), Total sugars (%) and Tannins (mg/100gm)content of Seedless late variety was 80.2, 18.0, 0.32, 4.40, 28.9, 13.1, 16.5 and 217.0 respectively,where as for Dehradun variety, it was 80.9, 17.0, 0.48, 5.07, 19.6, 10.2, 13.9 and 179.0 respectively.Physico-chemical analysis of litchi juice concentrate during storage: The effect of treatment andstorage on the physico-chemical parameters of litchi juice concentrate of two varieties viz. Seedlesslate and Dehradun are presented in Table 3. TSS: The total soluble solids followed an increasing trend during storage. Total soluble solidsincreased by 0.39 and 0.36 percent in treated concentrate of seedless late and Dehradun variety storedat low temperature. The increase in total soluble solids was mainly attributed to loss of moisture fromthe product during storage. Similar observations were reported by Sharma (1996) in grape, lime ando lemon juice concentrates stored at refrigerated temperatures (2-5 C) and Dharam pal (1995) inkinnow juice concentrate during storage. The effect of varieties, treatments and storage temperaturewas found non-significant (P>0.05) but storage period had significant effect (P<0.05) on total solublesolids of both varieties stored at low and ambient room temperature. Total solids: The overall mean value of total solids increased from 81.6 to 84.8 duringstorage. The percent increase in total solids was more at low temperature as compared to ambientroom temperature in both the varieties. Total solids increased by 4.6 and 4.3 percent in treatedconcentrates of Seedless late and Dehradun variety stored at low temperature. The slight increase in total solids seemed to be due to loss of moisture from the product during storage. Similar observationswere reported by Sharma et al (2001) in galgal juice concentrate stored in HDPE bottles at roomo o temperature (13.3-26.3 C) and low temperature (3-7 C) while Sharma (1996) in grape, lime ando lemon juice concentrates stored at refrigerated temperature (2-5 C). The varieties, treatments andstorage temperature had non-significant (P>0.05) effect on per cent total solids in the concentrateduring storage, while storage period had significant effect (P<0.05) on total solids of litchi juiceconcentrate. Moisture: The moisture content decreased in both treated and untreated concentrates of bothvarieties stored at low and ambient room temperature during storage. The moisture content decreasedby 20.4 and 19.9 per cent in treated concentrates of Seedless late and Dehradun variety, respectivelystored at low temperature. The decrease in moisture content was more at low temperature ascompared to ambient room temperature. Similar type of observations were reported by Singh et al(2002) in sugarcane juice concentrate stored at ambient room temperature and Sharma et al (2001) ino galgal juice concentrate stored in HDPE bottles at room temperature (13.3-26.3 C) and at lowo temperature (3-7 C) during storage. Acidity: The percent acidity decreased in both the varieties during storage. The overall meandecreased value of percent acidity ranged between 2.1 to 1.73 in both varieties. The decrease inacidity was more in untreated concentrates stored at ambient temperature whereas, treatedconcentrates stored at low temperature exhibited minimum decrease in acidity in both varieties. Thedecrease in percent acidity was observed more in Seedless late variety as compared to Dehradunvariety. The decrease in acidity may be attributed to chemical interactions between organicconstituents during storage. Similar observations were reported by Buglione and Lozano (2002) ingrape juice concentrate, Sharma et al (2001) in galgal juice concentrate, Sandhu et al (1990) inkinnow mandarin juice concentrate during storage. pH: The initial value of pH was recorded as 5.02 and 4.39 in treated concentrates of Dehradunand Seedless late variety while, initial values of pH was 5.04 and 4.47 in untreated concentrates ofDehradun and Seedless late variety. The pH value showed an increasing trend during storage in bothvarieties at all the storage temperatures. The observations revealed that increase in pH was more atambient room temperature as compared to low temperature. The increase in pH was recorded as 1.82and 1.79 percent in treated concentrates of Seedless late and Dehradun variety stored at lowtemperature. Similar results were reported by Buglione and Lozano (2002) in grape juice concentrate,Singh et al (2002) in sugarcane juice concentrate and Thakur et al (2000) in debittered kinnow juiceconcentrate during storage. Ascorbic acid: The ascorbic acid was significantly lost during storage in both the varieties.The overall mean decreased value ranged between 104.5 to 52.9 mg/100gm in both varieties. Ascorbic acid losses were maximum in untreated concentrates stored at ambient room temperature inboth varieties. The ascorbic acid decreased by 26.6 and 37.6 percent in treated concentrates ofDehradun and Seedless late variety stored at low temperature. The loss in ascorbic acid might be dueto effect of light, metal ions, processing and high temperature during storage. Similar types ofobservations were reported by Sharma et al (2001) in galgal juice concentrate, Ramteke and Eipeson(1990) in coorg mandarin juice concentrate, Sandhu et al (1990) in kinnow mandarin orange juiceconcentrate during storage.Reducing sugars: The reducing sugars followed an increasing trend during storage. Theoverall mean increase in percent reducing sugars ranged between 24.7 to 24.9 in both varieties. Theincrease in reducing sugar was higher in untreated concentrates stored at ambient room temperature inboth varieties. The percent increase in reducing sugars was recorded at 0.4 and 0.6 in treatedconcentrate of Seedless late and Dehradun variety stored at low temperature respectively. Theincrease in reducing sugars might be attributed to the inversion or hydrolysis of non-reducing sugarsinto reducing sugars. Similar results were reported by Singh et al (2002) in sugarcane juiceconcentrate, Sharma et al (2001) in galgal juice concentrate, Sandhu et al (1990) in kinnow mandarinorange juice concentrate during storage.Total sugars: The total sugars decreased in all the concentrates during storage. The overallmean decreased value of percent total sugar ranged between 58.1 to 52.6 for both varieties. Thetreated concentrates stored at low temperature resulted in minimum decrease in percent total sugarsduring storage. The decrease in total sugars was recorded as 1.9 and 4.5 percent in treatedconcentrates of Seedless late and Dehradun variety stored at low temperature. The decline in totalsugars during storage could be attributed to the involvement of sugars in browning reactions,formation of hydroxymethyl furfural and conversion of sugars to monosaccharides by acid hydrolysis.Similar trend was reported by Sharma et al (2001) in galgal juice concentrate and Sandhu et al (1985)in kinnow orange juice concentrate during storage. Tannins: Decrease in tannins was more pronounced in untreated concentrates stored atambient room temperature. The decrease in tannins was recorded as 37.1 and 27.5 in treatedconcentrates of Seedless late and Dehradun variety stored at low temperature. The decrease in tanninscontent is attributed to losses during processing, concentration and storage period at varioustemperatures. These findings correspond to the one reported by Kucreja (1997) in grape and maltajuice concentrate and Sharma (1996) in grape, lime and lemon juice concentrate during storage. Browning: The optical density was observed at 440nm. The overall mean increased value ofoptical density ranged from 0.385 to 0.662. The browning was more pronounced at ambient roomtemperature as compared to low temperature storage in both varieties. The increase in browning ofconcentrates during storage was due to reactions of amino acids with sugar, degradation of ascorbic acid and reactions of amino acids with other juice constituents i.e. phenols etc. The treatedconcentrates stored at low temperature exhibited minimum increase in optical density. Significantreduction in browning in treated concentrate might be attributed to the absence of sufficient aminoacids to react with sugars, ascorbic acid and phenols to cause browning. The percent increase inoptical density was 1.82 and 1.79 in treated concentrates of Seedless late and Dehradun variety storedat low temperature. The minimum browning in Dehradun variety may be due to higher retention ofascorbic acid as compared to Seedless late variety. The similar type of results were reported bySharma et al (2001) in galgal juice concentrate, Ramteke and Eipeson (1990) in coorg mandarin juiceconcentrate and Pruthi et al (1984) in malta orange juice concentrate during storage.Rheological measurementsApplicability of power law model: To understand better the rheological behaviour as well asrelationship between the composition and flow characteristics, power law model was fitted to thetorque data of the concentrate. Starting with the lowest speed, the shear rate vs shear stress dataobtained for ascending and descending curves were close together, indicating time-independent flowof the juice concentrates.Flow behaviour index: The mean values for flow behaviour index of the litchi juiceconcentrates ranged from 0.65 to o.97, indicating their moderate to mildly non-Newtonian nature(Muller 1973). The flow behaviour index for the various concentrates prepared from Dehradun varietywere similar to those of Seedless late variety. The concentrates stored at ambient room temperatureo (12-38 C) for 6 months showed flow behaviour index value significantly different from the sampleso o stored at low temperature (0-4 C). Using experimental temperature from 20-50 C, the power lawo flow behaviour index values slightly decreased with increase in temperature. At 50 C the flowo behaviour index were found in the range of 0.66 to 0.89 as compared to those of 0.66 to 0.97 at 20 C.The flow behaviour index values for the concentrates were observed to be decreasing slightly withstorage period as compared to controls. However, considerable decrease in flow behaviour index wasobserved for the concentrates prepared from Dehradun variety stored at low temperature for 6 months.A similar type of results were reported by Rao et al (1981) in tomato concentrates, Speers and Tung(1986) in xanthan gum dispersions while Rani and Bains (1987) in tomato ketchups. oConsistency index: Increase in the temperature from 20-50 C considerably influencethe consistency index value. The lower values for consistency index for concentrates were observed ato o o 50 C as compared to 20 C temperature. At 50 C the consistency index values for concentrates wereo nearly 15 folds lower than those at 20 C temperature. The consistency index values for variouso concentrates determined at 30-50 C for the concentrates stored at room temperature were similar too those of corresponding concentrates stored at room temperature. At 20 C the concentrates stored atlow temperature showed higher consistency index values than those stored at room temperature. Similarly, the Seedless late fresh juice concentrates stored at both room and low temperature showedconsiderably higher values than those of the corresponding Dehradun concentrates. These values werealso considerably higher than those of the preserved juice concentrates. However, the concentratesprepared from preserved juice of Dehradun variety showed higher consistency index values than thoseo of the corresponding concentrates from Seedless late variety at 20 C. The values of consistency indexwere found to increase with increase in storage time especially for those concentrates stored at lowtemperature. Whereas, negligible changes were observed in concentrates stored at low temperatureo except for the Seedless late fresh juice concentrates at 20 C which increased from 35.2 to 89.0 uponstorage for 6 months.Table 1. Percentage recovery of the various portions of litchi fruit of two varieties. Dehradun Seedless latePortion Weight (Kg) Percentage Weight (Kg) PercentageTotal fruit 2.0 - 2.0 -Peel 0.287 14.35 0.364 18.2Pulp 1.371 66.55 1.539 76.9Seed 0.342 17.10 0.097 4.85Juice 0.955 47.75 1.250 62.5Table 2. Chemical composition of juice of different litchi varietiesCharacter Varieties Dehradun Seedless Lateo TSS ( Brix) 17.0 18.0Moisture (%) 80.9 80.2Total solids (%) 19.1 19.8Acidity as citric acid (%) 0.48 0.32Ascorbic acid (mg/100gm) 19.6 28.9pH 5.07 4.4Reducing sugars, dextrose (%) 10.2 13.1Total sugars, dextrose (%) 13.9 16.5Tannins (mg/100gm) 179 217Table 3. Effect of treatment and storage on the physico-chemical parameters of litchi juice concentratePhysico- Storage Varietychemical periodDehradun Seedless lateparameter (months)Fresh Preserved Fresh PreservedRT LT RT LT RT LT RT LTo TSS ( Brix) 0 80.00 80.00 80.00 80.00 80.00 80.00 80.00 80.002 80.11 80.12 80.09 80.21 80.13 80.21 80.17 80.224 80.14 80.16 80.12 80.27 80.17 80.23 80.19 80.296 80.20 80.21 80.17 80.29 80.22 80.27 80.21 80.31LSD (0.05) 0.24 0.24 0.24 0.24 0.24 0.24 0.24 0.24Total solids 0 81.8 81.8 81.5 81.5 81.6 81.6 81.4 81.4 (%) 2 82.4 83.6 82.6 83.8 82.2 83.1 82.1 82.74 84.7 84.2 83.2 84.1 83.1 83.6 82.9 83.46 85.4 85.8 84.3 85.1 84.2 84.8 83.2 85.2LSD (0.05) 3.27 3.27 3.27 3.27 3.27 3.27 3.27 3.27Moisture 0 18.2 18.2 18.5 18.5 18.4 18.4 18.6 18.6(%) 2 17.6 16.4 17.4 16.2 17.8 16.9 17.9 17.34 15.3 15.8 16.8 15.9 16.9 16.4 17.1 16.66 14.6 14.2 15.7 14.9 15.8 15.2 16.8 14.8LSD (0.05) 3.18 3.18 3.18 3.18 3.18 3.18 3.18 3.18Acidity (%) 0 2.11 2.11 2.14 2.14 2.07 2.07 2.08 2.082 1.92 2.03 1.98 2.07 1.82 1.99 1.98 2.014 1.71 1.89 1.83 2.04 1.67 1.87 1.83 1.976 1.58 1.73 1.64 1.96 1.54 1.76 1.72 1.89LSD (0.05) 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18pH 0 5.04 5.04 5.02 5.02 4.47 4.47 4.39 4.392 5.09 5.06 5.08 5.05 4.51 4.43 4.46 4.414 5.18 5.11 5.15 5.08 4.55 4.47 4.50 4.456 5.29 5.17 5.22 5.11 4.61 4.50 4.54 4.47LSD (0.05) 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02Ascorbic 0 87.5 87.5 93.2 93.2 114.8 114.8 122.6 122.6acid2 63.3 72.6 67.0 78.7 87.2 98.4 91.5 108.8(mg/100gm)4 49.1 63.5 55.1 71.2 68.3 83.4 68.5 89.16 33.7 51.1 39.3 68.4 39.5 72.3 43.2 76.5LSD (0.05) 2.82 2.82 2.82 2.82 2.82 2.82 2.82 2.82Reducing 0 23.87 23.87 23.89 23.89 25.59 25.59 25.63 25.63sugars (%)2 24.03 23.96 23.98 23.94 25.73 25.69 25.72 25.684 24.12 24.03 24.07 23.99 25.87 25.73 25.76 25.726 24.26 24.09 24.11 24.05 26.03 25.81 25.86 25.74LSD (0.05) 1.63 1.63 1.63 1.63 1.63 1.63 1.63 1.63Total sugars 0 55.9 55.9 56.7 56.7 59.8 59.8 59.9 59.9(%) 2 52.4 51.5 51.2 55.7 53.1 58.7 57.8 59.44 49.6 51.0 50.3 54.9 51.3 57.8 56.4 58.96 47.4 49.9 48.8 54.1 49.4 57.2 55.9 58.7LSD (0.05) 1.62 1.62 1.62 1.62 1.62 1.62 1.62 1.62Tannins 0 789.3 789.3 816.1 816.1 852.3 852.3 917.7 917.7 (mg/100gm) 2 541.7 697.9 701.4 749.7 517.1 644.9 781.2 803.14 416.1 513.8 571.5 683.4 408.7 561.1 634.3 746.46 397.4 446.6 498.7 591.6 362.3 418.2 487.6 576.9LSD (0.05) 3.73 3.73 3.73 3.73 3.73 3.73 3.73 3.73Browning 0 0.051 0.051 0.022 0.022 0.058 0.058 0.023 0.023(at 440 nm) 2 0.776 0.121 0.587 0.058 0.805 0.137 0.627 0.0694 1.121 0.179 0.763 0.099 1.142 0.196 0.891 0.1416 1.173 0.218 0.989 0.146 1.187 0.225 1.152 0.172LSD (0.05) 0.242 0.242 0.242 0.242 0.242 0.242 0.242 0.242Colour 0 7.3 7.3 8.3 8.3 7.3 7.3 8.2 8.2scores2 5.9 7.1 7.6 8.4 5.4 6.9 6.9 8.24 5.8 6.9 6.4 8.2 5.3 6.8 6.3 8.16 4.9 6.5 5.9 7.8 4.8 6.5 6.2 7.5LSD (0.05) 0.61 0.61 0.61 0.61 0.61 0.61 0.61 0.61Flavour 0 7.7 7.7 7.5 7.5 7.6 7.6 7.4 7.4scores 2 7.6 7.6 6.7 7.3 6.6 6.9 6.6 7.24 5.8 7.5 5.9 6.9 6.4 6.8 6.5 6.86 3.7 5.5 4.0 6.8 5.5 5.9 5.7 6.6LSD (0.05) 0.17 0.17 0.17 0.17 0.17 0.17 0.17 0.17Taste scores 0 7.7 7.7 7.8 7.8 7.5 7.5 7.6 7.62 6.7 7.5 6.7 7.6 6.3 6.4 7.3 7.54 5.8 7.4 5.9 7.6 5.8 6.4 5.9 6.86 5.6 6.6 5.6 6.9 5.6 5.9 5.6 6.7LSD (0.05) 0.18 0.18 0.18 0.18 0.18 0.18 0.18 0.18Body scores 0 7.6 7.6 8.3 8.3 7.7 7.7 8.4 8.42 6.7 7.5 6.9 8.3 6.2 7.6 6.5 8.34 6.7 7.5 6.7 7.8 6.1 7.4 6.4 7.66 6.1 7.4 6.3 7.5 5.9 7.3 6.2 7.5LSD (0.05) 0.19 0.19 0.19 0.19 0.19 0.19 0.19 0.19Overall 0 7.8 7.8 7.9 7.9 7.8 7.8 7.9 7.9acceptability 2 6.9 7.7 7.0 7.8 6.8 7.6 6.9 7.7scores4 6.1 7.3 5.5 7.7 5.8 6.6 5.9 7.66 5.2 6.4 4.9 7.6 4.9 6.3 5.1 7.4LSD (0.05) 0.16 0.16 0.16 0.16 0.16 0.16 0.16 0.16 ReferencesAOAC 1985. 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Hawaii Agricultural ExperimentStation Bulletin.135 Effect of treatment and storage on Coefficient of viscosity (n) Variety Storage fresh Preservedperiodo o o o Room temperature (12-38 C) Low temperature (0-4 C) Room temperature (12-38 C) Low temperature (0-4 C)(months)o o o o o o o o o o o o o o o o 20 C 30 C 40 C 50 C 20 C 30 C 40 C 50 C 20 C 30 C 40 C 50 C 20 C 30 C 40 C 50 CDehradun 0 0.93 0.89 0.90 0.84 0.93 0.89 0.90 0.84 0.96 0.92 0.90 0.86 0.96 0.91 0.90 0.862 0.89 0.88 0.88 0.84 0.87 0.84 0.86 0.82 0.91 0.89 0.87 0.87 0.85 0.81 0.80 0.774 0.86 0.86 0.87 0.83 0.84 0.80 0.83 0.80 0.87 0.87 0.85 0.87 0.73 0.70 0.71 0.696 0.82 0.79 0.86 0.83 0.80 0.84 0.80 0.80 0.87 0.89 0.86 0.83 0.66 0.65 0.67 0.65LSD 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04(0.05)Seedless 0 0.91 0.90 0.90 0.86 0.91 0.90 0.90 0.86 0.97 0.94 0.92 0.89 0.97 0.94 0.92 0.89late2 0.86 0.88 0.89 0.85 0.86 0.86 0.85 0.84 0.94 0.89 0.89 0.85 0.93 0.89 0.89 0.844 0.80 0.86 0.88 0.85 0.82 0.82 0.81 0.83 0.91 0.89 0.85 0.81 0.90 0.85 0.87 0.796 0.88 0.88 0.84 0.87 0.76 0.76 0.72 0.82 0.86 0.89 0.86 0.83 0.84 0.86 0.84 0.82LSD 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04 0.04(0.05)Effect of treatment and storage on Consistency index(K) Variety Storage fresh Preserved periodo o o o Room temperature (12-38 C) Low temperature (0-4 C) Room temperature (12-38 C) Low temperature (0-4 C)(months)o o o o o o o o o o o o o o o o 20 C 30 C 40 C 50 C 20 C 30 C 40 C 50 C 20 C 30 C 40 C 50 C 20 C 30 C 40 C 50 CDehradun 0 59.68 18.17 7.31 4.52 59.68 18.17 7.31 4.52 47.84 14.34 5.76 2.96 47.84 14.34 5.76 2.962 58.88 19.06 7.71 4.45 71.01 24.73 8.32 4.75 50.22 15.98 6.29 3.03 87.49 29.54 13.28 6.724 58.08 19.95 8.12 4.37 82.34 31.29 9.32 4.98 52.61 17.64 6.83 3.12 127.1 44.74 20.82 10.496 57.06 20.69 7.47 3.81 76.07 25.59 10.28 4.89 41.98 13.17 5.51 2.91 155.9 64.45 23.29 10.83LSD 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08 4.08(0.05)Seedless 0 35.29 11.19 4.83 2.65 35.29 11.19 4.83 2.65 27.24 8.87 3.70 1.89 27.24 8.87 3.70 1.89late2 61.39 18.25 7.22 3.36 70.84 27.33 9.03 4.05 27.93 5.97 3.88 2.02 39.68 10.13 4.87 2.534 87.48 25.31 8.93 4.08 106.4 36.27 13.23 5.45 28.62 11.08 4.05 2.15 52.12 19.37 6.03 3.166 78.09 23.65 11.14 4.56 321.8 115.3 27.72 7.44 27.26 10.03 4.14 2.46 72.92 23.49 6.79 3.04LSD 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48 7.48(0.05)"