Freshly mature papaya (Carica papaya L.) and gooseberry (Emblica officinalis) were purchased from the local market of Allahabad.
Sorting and grading is essential to get suitable quality of fruit which was done by hand. The fruits were first thoroughly washed under running tap water to reduce soil, plant and debris load. Grading of fruit was done based on cleanliness, firmness, soundness, maturity, weight, color, size, shape, freedom from foreign matters, insect damage and mechanical injury. Undamaged fruits were selected with no symptoms of visible discoloration and soaked in warm water at (80˚C) for 2 min to reduce surface microbial load.
a) Papaya (Carica papaya L.)
From the graded papaya the pulp was extracted manually. It was homogenized in a mixer to obtain fine pulp.
b) Gooseberry (Emblica officinalis)
The washed gooseberry were boiled for 5 min in equal amount of water (by weight) to soften the outer skin. The boiled gooseberry were deseeded and pulped in a mixer; and the crude mixture pulp was sieved through an 800-micron sieve.
The papaya-gooseberry jam was developed by incorporation of gooseberry pulp in different ratios as shown in
| Treatments | Papaya | Gooseberry |
|---|---|---|
| T0 | 100 | 0 |
| T1 | 95 | 5 |
| T2 | 90 | 10 |
| T3 | 85 | 15 |
| T4 | 80 | 20 |
| T5 | 75 | 25 |
| T6 | 70 | 30 |
Fruits are preserved in the form of jam by relying upon the high solids-high acid principle. For the preparation of Jam fruit pulp was boiled with sufficient quantity of sugar to a reasonably thick consistency, firm enough to hold fruit issues in position [
Flow Chart for Papaya-Gooseberry Jam Preparation
Selection and preparation of fruit (papaya and gooseberry)
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Weighing of 200 g pulp
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Addition of 127 g sugar
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Cooking the pulp (cooking slowly with occasional stirring for 12 - 15 min)
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Adding together citric acid (1.7 g) + salt (1/2 pinch) + 2 g pectin
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Judging the end point (TSS-68.5% using refractometer ABBE)
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Packing (filled the hot jam into clean, dry sterilized bottles)
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Cooling, Capping and Storage (at ambient temperature)
The total soluble solids (TSS) of the fruit pulp and jam were determined using a hand refractometer (0% to 30% Brix, Model DIGT 0-30ATC for the pulp and 0 to 68% Brix Model DIGT 0-68ATC (The Optical Instruments Co. Ltd, Japan) for jam.
The proximate composition was analyzed according to the standard methods outlined by AOAC (2005) [
1) Determination of Moisture
5 g of the sample was weighed and taken in a tare porcelain dish (W1 g).Then dish was shaken till the contents were evenly distributed and placed in hot air oven, maintained at 105˚C ± 2˚C and dried for at least 2 hours. It was then cooled in desiccators and lowest weight was noted (W2 g).
Calculation:
Tared weight of the dish (W g);
Weight of dish with samples (W1 g);
Weight of the dish + sample after drying in oven (W2 g).
2) Determination of Total Ash
Ash comprises of the mineral content which was present in the sample which can be determined by igniting unknown amount of dried material in a muffle furnace. The dried material obtained from determination of moisture in a crucible dish was ignited on a blue flame of a burner till the smoke was given off. The porcelain/ crucible dish was then heated in a muffle furnace maintained at 500˚C ± 5˚C for 1 - 2 hours. It was cooled in a desecrator and weight was taken.
Calculation:
Weight of the dish + weight of dried sample = (W2 g);
Weight of dish + weight of ash = (W3 g).
3) Determination of Protein
5.0 g of sample was accurately weighed in a cupped filter paper and transfer the contents of filter paper into the kjeldahl flask. 10 g of digestion mixture (CuSO4 + K2SO4 + Selenium oxide) and 25 ml of concentrated H2SO4 was added. It was slowly warmed to minimize frothing, and then boiled until the solution was clean. The solution was allowed to cool and transferred to a 100 ml volumetric flask and make up the volume using distilled water. In the receiver of distillation apparatus, 10 ml of aliquot and 10 ml of 40% sodium hydroxide was added. Released ammonia was collected in 25 ml of 4% boric acid solution containing few drops of mixed indicator (Mixed indicator gives pink on distillation) which was distilled for half an hour, afterwards condenser outlet was disconnected. The obtained boric acid solution was titrated with 0.01 N sulphuric acid or 0.01 N Hydrochloric acids and for the blank water or sucrose was used in place of sample.
Calculation: 1 ml of 0.01N H2SO4 for = 0.0014 g
Titre volume = A − B ml
% crude protein = N ×conversion factor (6.25);
Volume of 0.1 N H2SO4 for sample = A;
Volume of 0.1 N H2SO4 for blank = B;
Weight of sample = W = 2 gm;
Volume made (V) = 100 ml;
Aliquot distilled (V1) = 10 ml.
4) Determination of Crude Fat
The extraction flask was weighed accurately (W1 g) and 2 g of the sample was transferred into the extraction thimble and was carefully placed in the extractor so that it was within its siphon height. Weighed extraction flask was connected to the extractor carrying the thimble and sufficient amount of petroleum ether was poured into the extractor to start the siphon and then filled about half the extraction flask. Extractor was connected to the condenser and flask was heated on a water bath or electric mental for 3 hours. The heat vaporizes the solvent and condensed in the condenser. The condensed solvent falls drop-wise into the thimble. The solvent extracts the fat present in the food. When the level of the solvent reached the siphon height, the whole of the ether flowed down into the flask below taking along with the extracted fat behind and the process was repeated. At the end of 3 hours by which time, at least 10 - 15 siphoning was taken, flask was removed carefully. The extract was transferred in a tarred conical flask and solvent was evaporated. Cooled in desiccators and weighed (W1 g). Drying, cooling and weighing or successive weighing not diffixing by more than 0.0002 g were obtained. Finally the weight was recorded (W2 g). Percentage of ether extract was calculated by multiplying the increase in weight of the extraction flask by 100.
Calculation:
Weight of sample (W);
Weight of flask (W1);
Weight of flask + fat (W2);
(Weight of flask + fat) − (Weight of flask) = (W2 − W1).
5) Determination of Crude Fiber
2 g of dried, fat free residue obtained after crude fat determination was weighed accurately and transferred into the one-liter conical flask. In a beaker, brought to boil the 200 ml dilute sulphuric acid (1.25%) and pour the boiling acid into the flask. The contents of the flask were boiled exactly for 30 minutes with constant shaking and the liquid level was maintained during boiling. At the end of 30 minutes remove the flask and filter its contents through fine lined pad held in a funnel and wash with boiling water until the washing are no longer acid to litmus.The entire residues was transferred back to the original digestion flask or beaker with a spatula and wash the residue on the linen into the digestion flask with 200 ml of boiling dilute NaOH (1.25%). The digestion flask was again boiled for exactly 30 minutes with constant rotation and maintained the liquid level as before. At the end of the specified period, the residue was washed thoroughly with boiling water till free from alkali and transferred to the prepared gooch crucible dried to constant weigh at 105˚C in an hot air oven (W g). The residue was again washed with 15 ml of 95% ethyl alcohol. The content in gooch crucible was dried at 105˚C and cooled in desiccators and weighed to constant weight (W1 g). The gooch crucible and its contents were transferred in a muffle furnace and ignited at 600˚C ± 20˚C for 1 hour, until all carbonaceous matter is burnt. Finally, cooled the gooch crucible containing the ash in desiccators and weighed (W2 g).
Calculation:
Tare weight of Gooch crucible = (W g);
Weight of Gooch crucible + sample (ash) = (W2 g);
Weight of residue = (W2 − W)g.
6) Determination of Carbohydrate
Total carbohydrate by difference was calculated by subtracting the sum of percentage of protein, fat, ash and moisture. Carbohydrate was divided into two groups’ crude fiber and nitrogen free extract (NFE). Total carbohydrate include crude fiber also, but NFE was calculated by subtracting the sum of percentage of ash, crude fiber, fat, protein and moisture from hundred.
Calculation:
7) Determination of Caloric Value
Energy value of the sample was calculated by multiplying the figure for percentage of protein, fat and carbohydrate by 4, 9 and 4 respectively and adding the figures obtained.
Calculation:
The mineral composition was analyzed according to the standard methods as described in Ranganna [
1) Determination of Calcium
10 g of ash sample was taken and 5 ml of concentrated hydrochloric acid was added to rinse the upper part of dish and evaporated to dryness. The residue was dissolved by adding 2 ml of hydrochloric acid. Covered it with watch glass and filtered the ash solution into 100 ml volumetric flask and diluted to 100 ml volume. 50 ml of ash solution was taken in a 250 ml conical flask and 8 - 10 drops of bromocresol green indicator solution was added gradually. 20% of sodium acetate was added until the solution turns blue (pH at this point was 4.8 - 5.0) covered with watch glass and heated to boiling. Slowly add 3% of oxalic acid drop wise, until the color of solution was green (pH at this point should be 4.4 to 4.6 which is optimum for precipitation of calcium oxalate). Continue boiling for one minute and allow it to stand until clear or overnight. The supernatant solution was filtered and discarded through Whatman no. 42 filter paper. Wash the conical flask and precipitate, filter it with 50 ml of dilute ammonium hydroxide solution, using small portions at a time then again wash it with some hot distilled water. Lastly, the filter paper was washed with a mixture of 125 ml distilled water and 5 ml concentrated sulphuric acid breaking the tip of filter paper and collecting the washing in original empty conical flask. Heat the solution to 90˚C and titrated with 0.1N potassium permagnate solution until pink color was obtained.
Calculation: 1ml of 0.1N KMnO4 = 2 mg Calcium
Weight of the sample (W) = 5 g;
Volume of ash solution made (V) = 100 ml;
Volume of ash solution used (V1) = 50 ml;
Volume of 0.1N KMnO4 used for sample = A;
Volume of 0.1N KMnO4 used for blank = B.
2) Determination of Phosphorous
Phosphorus reacts with molybdic acid to form phosphomolybdate complex. It is then reduced with aminonaphthol-sulphuric acid to complex molybdenum blue, which is measured at 650nm.In 5 ml of ash solution, 5 ml of molybdate reagent and 2 ml of aminonaphthol-sulphonic acid solution was added and the volume make up with distilled water to 50 ml. The blank was similarly prepared by using distilled water in place of the sample. The solution was incubated for 10 minutes and the absorbance was measured at 650 nm setting blank at 100% transmission.
Calculation:
3) Determination of Ascorbic Acid (Vitamin C)
This method is based upon the reduction of the dye 2-6 dicholoro-phenol endophenol by an acid solution of ascorbic acid in the absence of interfering substance (Cu++, Fe++, and Sn++, etc.). The reduction capacity of the extract of the sample is directly proportional to the ascorbic acid content.
For the preparation of standard, 20 mg of pure ascorbic acid was accurately weighed on a tared black glazed paper and transferred to a clean 100 ml volumetric flask. Dissolve in 1% oxalic acid solution and make up the volume to the mark with the same acid. For the preparation of dye indicator, 50mg of sodium salt of 2,6 dicholorophenol-endophenol was dissolved in 150 ml of hot water containing 42mg of sodium carbonate. The solution was cooled and diluted with 200 ml of distill water and stored in a glass bottle and kept in a refrigerator or away from sunlight at 3˚C. For the standardization of dye solution, 5 ml of ascorbic acid was pipette out in a conical flask and 5 ml of 1% oxalic acid solution was added and titrated with the dye-indicator to a fame end point that persists beyond 15 seconds. The ascorbic acid equivalent of the dye was calculated in mg/ml.
1 gm of sample was weighed and dissolves in 10 ml distilled water and filtered through muslin cloth.10ml of the filtrate was taken in a 100 ml volumetric flask and diluted to the mark with 1% oxalic acid solution. Filter the diluted solution through dry filter paper if necessary. Pipette out 10ml or 25ml aliquot of the filtrate into a small flask and titrate immediately with the standardized dye indicator solution to a pink end point.
Calculation:
E = Ascorbic acid equivalent of the dye in mg/ml;
V = ml of the dye indicator used in the titration (VR);
V1 = Volume to which the fruit juice is diluted (500 ml);
V2 =Volume of filtrate taken for the titration (10 - 20 ml);
W= Weight or volume of fruit juice initially taken for the determination.
4) Determination of Beta-Carotene
Carotenoids are generally separated by chromatography. The method is based upon the separation of the biologically active carotenoid pigments from the total carotenoid pigment in an extract by using an adsorbent having varying affinities for the different pigments. 10 g of sample was in pastel mortar with 40 ml acetone and filtered. 0.1 g MgO2 diluted with 60 ml of hexane was added in the above sample and filtered. The filtrate was transferred in a separating funnel and two layers were separated. Lower layer was decanted and the upper transparent layer of hexane was taken for estimation. The upper layer was transferred into a 100 ml volumetric flask and volume make up with 100 ml hexane. For the preparation of column, aluminum and sodium sulphate was taken in 1:1 ratio (20 g + 20 g). The silica gel was poured into the column using a 10 ml beaker and the suction pump was used to force air into the column and pack the silica gel. A space of 4 - 5 cm was left on top of the adsorbent for the addition of solvent (hexanes and acetone).Hexanes and acetone solution was added to the top of the silica gel and when the bottom solvent level is at the bottom of the column, the pre-elution process is completed and the column is ready to load. The sample to be purified is dissolved in a small amount of solvent, such as hexanes or acetone and loaded into the column. The sample was collected in a beaker and the absorption was noted by using spectrophotometer at 436 nm.
Calculation:
5) Percent Anti Radical Activity
10 mg of sample is taken and 10 ml of acidified methanol is added in the sample. It was heated on a water bath at 40˚C for 20 minutes. It was filtered and the supernatant is centrifuged for two minutes. Finally the resulting supernatants were used as test samples. For the preparation of DPPH (2, 2-diphenyl-1-picrylhydrazyl) solution, 4.3 mg of DPPH was dissolved in 3.3 ml of methanol which was protected from light by covering the test tubes. Pure methanol was used as blank solution. 100 µl of sample extract was taken in a test tube and diluted with 200 µl of methanol. The volume make up with 2.7 ml methanol again up to 3 ml. Then 150 µl of DPPH solution was added and test tubes were covered with brown paper or aluminum foil and mixed properly. The solution was incubated for 15 minutes at room temperature and the absorbance was recorded at 515 nm by spectrophotometer [
The free radical scavenging activity (FRSA) (% antioxidant activity) was calculated by using the following equation:
The developed papaya-gooseberry jams were served to 30 semi trained panelists group for evaluating color, consistency, flavor, taste, and overall acceptability on a 9 point hedonic scale with a scores ranging from 9 to1 which represents like extremely and dislike extremely respectively. The quality parameters were quantified and the mean scores of the three evaluations were calculated.
The collected data was analyzed and tabulated statistically and expressed as percentage; mean scores, standard error of mean, critical difference, t-test and one-way analysis of variance (ANOVA) by using statistical software SPSS version 12.0. To indicate statistically significant difference P ≤ 0.05 values were considered.