PDF《American Journal of Applied》

American Journal of Applied Sciences

6 (7): 1341-1346,

2009 ISSN 1546-9239 ?

2009 Science Publications Corresponding Author: Ruzainah Ali Jaafar, Department of Bioengineering, Section of Biosystem and Bioprocess Engineering Technology, University Kuala Lumpur-Malaysian, Institute of Chemical and Bioengineering Technology, Taboh Naning, Alor Gajah, Melaka, Malaysia Tel: 06-5512022 Fax: 06-5512005

1341 Proximate Analysis of Dragon Fruit (Hylecereus polyhizus)

1 Ruzainah Ali Jaafar,

1 Ahmad Ridhwan Bin Abdul Rahman,

1 Nor Zaini Che Mahmod and

2 R.

Vasudevan

1 Department of Bioengineering, Section of Biosystem and Bioprocess Engineering Technology, University Kuala Lumpur-Malaysian, Institute of Chemical and Bioengineering Technology, Taboh Naning, Alor Gajah, Melaka, Malaysia

2 Molecular Biology Lab, Department of Biomedical Science, Faculty of Medicine and Health Sciences, University Putra Malaysia, Selangor, Malaysia Abstract: Problem statement: Dragon fruit (Hylecereus polyhizus) is well known for the rich nutrient contents and it is commercially available worldwide for improving many health problems. Several studies show the proximity value of red pitaya fruits but the nutrient composition of the stem has not been extensively studied. Approach: This study was carried out to measure the proximate analysis of moisture content, water activity, ash, crude protein, crude fat, crude fiber, glucose and ascorbic acids content in premature and mature of dragon fruit. The dried powder was produced from the stem of dragon fruit and the proximate analysis of dragon fruit stem was compared between freeze drying process and drying oven process. Results: Results of this study showed that 96% moisture;

0.270 g of protein;

0.552 g L?1 glucose and 132.95 mg L?1 ascorbic acid of dragon fruit stem found higher than the fruit flesh of the dragon fruit. Conclusion: The premature stem had higher values than the mature stem of the dragon fruit which may helpful in preventing the risk factors of certain diseases. Key words: Red pitaya, proximate analysis, Malaysia INTRODUCTION Dragon fruit or red pitaya belongs to the Cactaceae family from the subfamily Cactoidea of the tribe Cactea[1] . In Malaysia, the red pitaya or dragon fruit is commonly called as buah naga . Among the red pitaya species Hylocereus polyrhizus (Red flesh) fruits are edible and it has a great source of vitamin C and water soluble fiber[2] . Hylocereus polyrhizus is a small fruit climbing cactus that has received world-wide recognition as an ornamental plant for its large, scented, night-blooming flowers. The red skin fruit weighed up to 1kg has translucent dark-red flesh considered as a rich source of nutrients and minerals such as vitamin B1, vitamin B2, vitamin B3 and vitamin C, protein, fat, carbohydrate, crude fiber, flavonoid, thiamin, niacin, pyridoxine, kobalamin, glucose, phenolic, betacyanins, polyphenol, carotene, phosphorus, iron and phytoalbumin[3] . It is also rich in phytoalbumins which are highly valued for their antioxidant properties[4] . Hylocereus polyrhizus is rich in fibers, vitamin C, minerals and phytoalbumins which are highly valued for their antioxidant properties. The dragon fruit helps the digestive process, prevent colon cancer and diabetes, neutralize toxic substances such as heavy metal, reduce cholesterol levels and high blood pressure and consumed regularly the dragon fruit can help against asthma and cough. It is also rich with potassium, protein, fiber, sodium and calcium which goods for health than other fruits[5] . There are three techniques for foods drying are commonly used such as sun drying, drying oven and freeze drying. First, the drying process is heated high to force out the moisture from food. Secondly, dry air to absorb the released moisture and finally the air movement to carried out the moisture away from the food. The freeze dried product should be passing through all the three stages which are freezing process, primary and secondary drying process. Freeze-drying is a technique that results in high-quality dehydrated products due to the absence of liquid water and the low temperatures required in the process. The solid state of water during freeze-drying protects the primary structure and minimizes changes in the shape of the product, with minimal reduction of volume[6] . The drying process may alter these properties, resulting in products with modified texture, Am. J. Applied Sci.,