Comparative evaluation of Pakistani Ber varieties for development of jam

Ber fruit possess antioxidant properties, which may exert higher health promoting effects than apply and other common fruits.

Comparative evaluation of Pakistani Ber varieties for development of jamHerbs:

Herbs as medicine have been using for more than 5000 years ago. Plant materials like leaves, stem, fruit, flower, roots, seeds and barks are used for their herbal perspective. There are 250,000 plant species and upto 80,000 of them are identified as medicinal plants. These traditional medicinal herbs provide curative and preventive effects in fighting diseases that may be due to those minute amounts of essential trace elements which are present in it. The local herbs native of Pakistan consisted of fruits commonly named as Anardana (dried pomegranate), Ber (jujube) and Kabab chini (cubeb).

Therapeutic potential of fruits:

Fruits may be sour or sweet fleshy product of plants which are edible in raw state. They are good sources of bio active compounds (which include phenolic contents and fiber) and vitamins along with sugars. Fruits have been strongly linked with reduction of major chronic degenerative diseases risk.  Individual should have 400 g of fruits per day according to the World Health Organization (WHO).

Fruits are mostly categorized as high perishable food commodity due to higher moisture contents in it. Fruits can be preserved for long time with least deterioration by reducing its moisture contents (dehydration process). There is a series of therapeutic and nutritional effects of fruits on human health mainly due to the presence of phyto-chemicals that have anti oxidant properties. The fact helps to increase the consumption of fruits from last few years. Recent studies showed that often consumption of fruits may lead to decrease signs of aging and help in prevention of certain illness including cardiovascular and cancer like diseases which are due to cell oxidative stress caused by free radicals.  However these phyto-chemical compounds present in fruits are strongly affected by genetic as well as environmental factors which involve fruit maturity stage at time of harvest, harvesting time, geographic region of production and post harvest conditions including handling, processing and storage.

Jujube:

 Jujube is multipurpose fruit tree primarily grown for the sake of delicious fruit and have been used for more than 4000 years for consumption and medicional purposes. Ziziphus belongs to family Rhamnacea which have 170 species e.g. jujube, lotus, spina christi, mucronata, florid Ziziphus, vulgaris, nummularia, spinosa, oenoplia Mill and many others. They are commonly found in sub-tropicaland tropical regions. Local name Ber English name Jujube Botanical name Ziziphus jujuba.  

Fruit shape varied from obviate, oval, round, oblate to ovate, whereas length of fruit ranged from 1.1 – 4.7 cm. Now a day these are grown in southern Europe, North Africa, Russia and the Middle East. In China more than 70 species of Ziziphus have been found. Two major cultivated jujubes in world are chines jujube (Z. jujube mill) and Z. mauritiana Lam other name Indian jujube. While number of other jujubes are also produced in local areas. Because of its growth in arid and semiarid zones the fruit is known as “apple of desert”.

As ber tree has very low requirement of water so production of fruit will get even in low rain fall. Depending upon climatic conditions and age per tree yield can be between 80 to 200 kg. China produces 90% of total ber fruit worldwide. 60 lac quintals of ber fruit were produced by China from 30,000 ha area. While in Pakistan annual production of ber is 27950 tones over an area of 5425 hectares. During last decades many varieties were import in Sub continent to mix with Thai varieties in result to get new varieties with high nutritional values.  

In Pakistan major areas regarding ber production are Multan, Sargodha, Bahawalpur, Jhang, Faisalabad (Punjab province) and Hyderabad, Nawabshah, Malair area of Karachi, Tandojam and Mirpurkhas (sindh province) where well known ber varieties are Bhawalpur selection 1, Allu Bukhara, Bhawalpur selection 2, karela, Umran, Khobani, Fauladi, Suffon, Anokhi, Mehmood wali, Ajooba, Yazman local, Saddqia, Pak white, Gorh, Dilbhar, Dehli white. Z. Mauritiana Lamk. is most abundantly present in various areas of Sindh province ( Pakistan).

Many ber varieties are grown in Pakistan but no serious research has done to classify our available varieties.   China is the only country who made serious attempts on jujube researches. Ber fruit contain a number of bio active phyto-chemicals, amino acids, calcium, iron, phenolic acids, phosphorous, vitamin A and ascorbic acid. Nutritional value of Z. Mauritiana was found higher than other common fruits like orange, mango, strawberry and guava.  Fully ripe fruits have higher values of carotene, vitamin C, phosphorous, protein and calcium as compare to apple. Due to its nutritional value this multipurpose tree need to exploit on large scale. As compare to other edible fruits per day one jujube fruit fulfill adult’s diet requirements of vitamin B and C as per WHO/FAO recommendation.

Antioxidants:

Phenolic compounds group include phenolic acids that are secondary metabolites. Within cells these are present in conjugated and free forms. Nine different phenolic acids namely ferulic acid, protocatechuic acid, chlorogenic acid, p-hydroxybenzoic acid, ortho-paracoumaric acids, caffeic acid, vanillic acid and vanillin were identified in pakistani ber varieteies.  Secondary metabolites present in jujube are the basic chemicals regarding health benefits and to cure diseases e.g. urinary troubles, liver diseases, allergies, depression.

As for as flavonoids concerned  twelve flavoinds present in ber fruit including galactoside, rutinoside, quercetin glucoside, quercetin robinobioside, quercetin rhamnoside, luteolin malonylglucoside and naringenin. It has bioflavonoid which perform antioxidant, antibacterial and anti-inflammatory properties. It regulates blood circulation and promotes bile production. It is well known from Arabia to China with great potential for ethnomedicinal use. To maintain population health in developing countries there is urgent need of finding new and cheaper sources of dietary fiber. Dietary fiber (DF) exists in two forms soluble and insoluble. Whereas the food obtained from plant sources have combination of both. The crude mucilage isolated from Ziziphus Mauritiana Lamk. have neutracutical potential. Crude Ziziphus Mauritiana mucilage helps to control the postprandial serum glucose level and its mechanism consist of 3 steps. Firstly increase viscosity of small  intestine content and reduce diffusion of glucose. Secondly glucose molecules may bind with Ziziphus Mauritiana mucilage in this way availability of glucose in small intestine decreases. Lastly it retards amylase action and postponesthe the release of glucose because of fiber associated total polyphenols presence.

Jujube products:

Dried jujubes are used as sweetened tea syrup, snacks, soups, pickles, jam, paste and dried fruit candies. Keeping in view the need of the time, the present project is design to evaluate the physicochemical and nutritional characteristics of selected ber varieties of Pakistan. To extend the use of this miracle fruit ber jam was prepared, that will prove a step towards the value addition of this fruits.

Conclusion:

Vegetables and fruits are rich in antioxidant and can be experimented with, to yield generally recognized as safe and economically feasible amounts of antioxidant to be utilized in such food products. Many plant polyphenols, such as ellagic acid, catechins, chlorogenic caffeic and ferulic acid, as well as their dietary sources, have been shown to act as potent anti-mutagenic and anti-carcinogenic agents.

Ber fruit contain substantial amount of phenolic contents such as nine phenolic acids, protocatechuic acid, p-hydroxybenzoic acid, ferulic acid, chlorogenic acid, vanillic acid, caffeic acid, vanillin, ortho- and paracoumaric acids, were identified in pakistani ber varieteies. Ziziphus jujube belongs to Rhamnacea family locally known as ber and widely in the sub-tropical and tropical areas worldwide. It is consumed fresh and in commercially processed products such as marmalade juices pickles and wins.

This research was performed to study physic-chemical attributes of 3 local varieties of Ber in Faisalabad namely Anokhi(T3), Mehmood wali (T2) and Dehli White (T1). To made a high shelf life product which can be available in off season and decrease the post harvest losses of this useful fruit was another objective of the study. Jam  of these 3 varities was made individually and mixture of all three. Fruits were subjected to the physic-chemical analysis before and after product formation and storage study of jams was also performed during 1 month.

Flavor changes may occur during jam preparation of fruits. For better jam quality storage conditions are key factor. Generally fruit jam stored at high temperature which ultimately lead towards a significant loss in sensorial and nutritional properties. Incomplete association of pectin molecules formed gel network which embedded water molecules of system. Flavor of spreads and jams strongly depend upon maturity or ripeness of fruit, as far as jam preparation concerned fully ripen fruits should be used. Over ripe fruits are highly vulnerable to texture degradation and microbial spoilage so such fruits are not acceptable at industrial level for the sake of jam preparation. Product development considers a valuable operation in jam industry as it majorly involves consumer’s choice. By changing pulp concentration and other ingredients gel structure of jam can modify often detected as mouth feel or texture. Mouth feel is influenced by the texture.

The results obtained from different parameters were statistically analyzed in order to find the best ber variety regarding ber jam production. Highest Total Phenolic content was reported in (T3) 3.79%,. Where as  values for  Total Flavonoid content 1.53%, 1.13% and 0.74% ; fiber content 1.760%, 1.730% and 1.690% ; vitamin C content 39.82%, 38.03% and 36.10% were found respectively. In case of antioxidant activity and all other quality and sensory parameters of ber jam T3 exhibited highest Total soluble solids 74.77%, flavor 8.37, vitamin C 41.22% and overall acceptability 8.02 where T4 (mixed jam) have more Total phenolic contents 5.95% and fiber 3.85%. Lowest antioxidant activity was found in T0 (control) indicated that by incorporating ber fruit with other fruits it is possible to enhance the nutritional quality and improved antioxidant properties of jams and other similar products. 

It is concluded by this study that best ber jam according to its quality parameters and sensory attributes was T3. Substantial quantities of antioxidant compounds were reported which exhibited strong inhibition against the free radicals. The measured quality attributes of three local ber varieties prepared by adding 45% ber fruit pulp were comparable or even better than those of commercial jam products (apple, mango).  The data showed that jujube fruit jam is not only a good source of phenolic contents but its sensory attributes were also appreciable.

The stability of product and kinetics of the changes occurred in quality attributes were minute. So ber fruit can utilized as an economically feasible as well as natural source of good nutrition in food products in order to minimize the post harvest losses of this fruit. In raw ber fruit variety Anokhi has maximum sweetness, where Dehli white has a sweet and sour kind of flavor so for further studies pickles can be made from it. Drying of jujube is another option, powder can be used for flavor enhancer in drinks and soups (may be as a soup thickener).

aysha saleem

Food Technologist, Quality Assurance Manager, Free lancer,

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