Studies on Effect of Different Extraction Methods on The Quality of Pomegranate Juice And Preparation of Spiced Pomegranate Juice

Introduction

Pomegranate is an important crop for dry land areas in India. The two varieties i.e. Ganesh and Arakta were used for the present study. Kandhari/ Arakta which is large sized with deep red rind, arils dark blood red, hard seedsand slightly bitter juice. And Ganesh variety with Medium sized; soft seeds; pinkish flesh and juice with agreeable taste. Generally these fruits are used for table purpose; however they are also processed into varieties of products like juice, squash, syrup, wine, anarrub and anardana (La Rae, 1969). The special structure of fruit is one of main factors which limit its industrial processing. The fruits can be preserved and processed into different products like juice, squash, syrup, jelly, wine, anardana and canned beverages.

The juice from fresh pomegranate fruit is an excellent cooling beverage for alleviating thirst in cases of fever and sickness. It acts on liver, heart and kidneys and tones up their functions. It supplies the required minerals and helps the liver to preserve the vitamin from the food. It also increases the body resistance against infections. The juice is an excellent cooling beverage for alleviating thirst in cases of fevers and sickness. It also increases the body resistance against infections (Seeram et al., 2008). The juice particularly tannin fraction, reduces lipid peroxidation, cellular cholesterol, accumulation and development of atherosclerosis (Esmaillzadeh et al., 2004). Commercialization of process technology and pomegranates products in market is very important to improve economy. Knowing the importance of health benefits of pomegranate and all related aspects, the present investigation entitled “Studies on effect of different extraction methods on the quality of pomegranate juice and preparation of spiced Pomegranate juice” was carried out to standardize the recipe for preparation of spiced pomegranate juice by using selected processing techniques and explore the prepared product for commercial use. Further efforts were made to evaluate the chemical quality of prepared pomegranate juice enriched with spices for their nutritional and organoleptic quality. Techno-economic feasibility of spiced pomegranate juice was also assessed.

Materials And Methods

Pomegranate fruits of cultivars Ganesh and Arakta were selected from local market. The fruits of uniform size, colour and maturity were selected by visual observation and used as experimental material. Spices like cardamom, clove, fennel and other material required for preparation of spiced Pomegranate juice were procured from local market.

ProximateAnalysis of spiced pomegranate juice

Prepared pomegranate juice and spiced pomegranate juice were analyzed for its chemical quality by standard methods (AOAC, 1990).

Sensorial Analysis

Sensory analysis of prepared products was performed by using standard method (Amerine et al., 1987).

Statistical analysis

The analysis of variance of the data obtained was done by using Completely Randomized Design (CRD) for different treatments as per the methods given by Panse and Sukhatme (1967). The analysis of variance revealed at significance of P < 0.05 level, S.E. and C.D. at 5 % level is mentioned wherever required.

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Figure 1:

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Figure 1: Clarification of Pomegranate Juice

Extraction of Juice

Hand Press Method (M1)

Pomegranate juice arils were separated manually from fruit. The juice was extracted by crushing the arils followed by pressing through two to three layers of muslin cloth

Domestic Mixer Method (M2)

Pomegranate juice arils were separated manually from fruit. The sepa-rated arils were crushed in domestic mixer. The juice obtained is strained by using muslin cloth.

Clarification of juice

The filtered pomegranate juice was used for clarification using commercially available fining agent gelatin and bentonite. Firstly juice was filtered through muslin cloth. To this juice bentonite at 0.5% of juice was added and juice was held for 4 hrs. Then the treated juice was filtered through muslin cloth. This juice was pasteurized at 820C for 15 min. to get clarified juice.

Storage Studies of Pomegranate Juice and spiced Pomegranate juice

Pomegranate spiced juice was analyzed for various attributes on every 15th,30th,45th,60thday and shelf life studies were carried out for a period of 2 months. The pomegranate juice samples were stored at ambient temperature (27-280C) and at refrigerated temperature (4-50C).

Assessment of Energy Value of value added products

Theoretical energy value of the spiced juice was calculated on the basis of proximate chemical compo-sition.

Assessment of Techno-Economical Feasibility

The production cost of spiced juice prepared from pomegranate was calculated by considering the cost of raw material, processing and packaging cost.

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Table1:

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Table 1: Effect of extraction method on yield of pomegranate juice

Results And Discussion

It is observed from Table1 that on the basis of whole fruit, percent juice yield by hand press method (M1) and domestic mixer method (M2) in Ganesh cultivar was 50.25 and 55.50 percent while in Arakta cultivar 50.20 and 55.00 percent respectively. It was noted that higher juice yield was obtained for both cultivars using mixer due to crushing of whole seeds. The juice obtained by using mixer had higher turbidity and increases the load of clarification of juice. Comeroglu et al (1992) showed that juice yield of pomegranate was 50 percent of its whole fruit and 60 percent of arils.

Effect of different extraction methods on chemi-cal parameters of Pomegranate juice

The TSS, acidity, pH, total sugar, reducing sugar and non-reducing sugar in juice extracted by method M1 for Ganesh cultivar were 150Bx, 0.3 percent, 3.2, 13.00 percent, 12.30 percent and 1.7 percent. Whereas juice extracted by method M2 showed values were 15.500Bx,0.32 percent, 3.1, 13.50 percent, 12.00 percent and 1.5 percent respectively. It was observed that there was slight increase in TSS in method M2 due to crushing of seeds. In case of Arakta cultivar there is slight change in values of chemical parameters like Ganesh variety.

Miguel et al (2004) reported that there is no significant difference in content of sugars, acidity in juices obtained through application of different extraction methods.

Polyphenols are most prominent antioxidants in our diet. Among polyphenols, anthocyanins are predominant group of polyphenol with high colouring potential (Wrolostad et al 2005). Ascorbic acid is also well known for its antioxidant properties. It was found that the concentration of exreacted anthocyanins and ascorbic acid were found to be more by domestic mixer extraction method.

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Table2:

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Table 2: Effect of different extraction methods on chemical parameters of Pomegranate juice

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Table3:

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Table 3: Effect of Extraction Methods on Antioxidant Properties of Pomegranate Juice

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Table4:

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Table 4: Effect of Extraction Methods on Mineral Content of Pomegranate Juice

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Table5:

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Table 5: Sensory evaluation of spiced pomegranate juice

Effect of storage temperature on quality of juice

It is observed from values in Table 6 that values of TSS, Total sugars, reducing sugars and non-reducing sugar of pomegranate juice increased during storage. It was noted that TSS of juice was initially 150Bx and after 60 days it was 15.50Bx at ambient temperature and 160Bx at refrigeration temperature. Increase in TSS was found to be associated with increase in sugars.

These results were in agreement with those reported by Palaniswamy and Muthukrishnan (1974).

It was found that total sugar, reducing sugars and nonreducing sugar content was increased during storage at both room and refrigeration temperature. The pH of juice showed not much change during storage. Acidity and ascorbic acid content of juice showed decreasing trend during storage period. This decrease in acidity could be due to chemical interactions between organic constituents of the juice particularly organic acids and anthocyanins Palaniswamy and Muthukrishnan (1974). Similar results were reported by Khurdiya and Anand (1981). At room temperature juice when stored for two months decrease in ascorbic acid from 8.5mg/100g to 6.5mg/100g was observed. While at refrigeration temperature ascorbic acid was found to be reduced upto 6.8 mg/100g.

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Table6:

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Table 6: Effect of storage temperature on quality of juiceriety

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Table7:

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Table 7: Energy value of prepared products

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Table8:

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Table 8: Cost of spiced pomegranate juice

Conclusion

It can be concluded that a good quality spiced pomegranate juice can be prepared from pomegranate fruits. In case of extraction methods for juice extraction, the domestic mixer method was found in relation to yield and other quality characteristics like TSS.Pomegranate cultivar Arakta is suitable for preparation of highly nutritive and palatable spiced Pomegranate juice with its attractive colour Hence this product could be recommended for commercial exploitation..Nevertheless, the pomegranate has commercial potential for production of health related food products. But the systematic and organized approach should be followed with other sophisticated methods for retention of other bio-active components, storage life, clinical studies and packaging requirements.