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Proximate Analysis of Dragon Fruit (Hylecereus polyhizus)

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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.
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... The fruit is edible, weighs up to one kilogram and is 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, cobalamin, glucose, phenolic, betacyanins, polyphenol, carotene, phosphorus, iron and phytoalbumins. It is also abundant in phytoalbumins which are rich in antioxidant properties (Jaafar, et al., 2009). ...
... The moisture content of the peel of 6.66 percent is lower than the moisture content acceptable for useful storage for rice flour (9.6%), wheat flour (10.7%) and corn flour (10.5%) (Abdullah et al., 2000). The low moisture content suggests that it will increase the keeping quality of the powder (Jaafar et al., (2009). The result has a significant impact on its shelf life and microbial activity of the powder. ...
... Ether extract (fat) values of 0.72 ± 0.04 and 0.41 ± 0.08 g.100 g -1 were found for red and yellow pitahaya, respectively, which were higher than those reported by Mercado-Silva (2018), for pitahaya fruits from Brazil (of 0.1 g.100 g-1). On the other hand, Jaafar et al. (2009), studied the proximal composition of red pulp pitahaya of Hylocereus spp. species from Malaysia, finding fat values in the range of 0.21 to 0.61 g.100 g -1 , slightly lower than those obtained in the present study (0.72 ± 0.04 g. 100 g -1 ). ...
... These values are within the range of 4.0 -25.8 mg.100 g -1 , in pitahaya grown in tropical areas, reported by Mercado-Silva (2018), Obregón-La Rosa et al. (2021), Cañar et al. (2014), Menezes-Cordeiro et al. (2015), Morales de León et al. (2015) and Gunasena et al. (2006). Jaafar et al. (2009), analyzed fruits of Hylocereus polyrhizus with red peel and pulp, finding vitamin C values (8 -9 mg.100 g -1 ) lower than those found in the present study. ...
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Pitahaya, known as "dragon fruit", is an exotic fruit with excellent nutritional properties; however, the species from the Peruvian coast have been little studied. The objective of the present study was to determine the physicochemical and nutritional composition of two species of pitahaya Hylocereus undatus (Haw.) Britt and Rose (red pitahaya) and Hylocereus megalanthus (yellow pitahaya), cultivated in the central coast of Peru. Proximal analysis, physicochemical and mineral contents were determined by standardized methods. From the results found, the fiber content of red pitahaya (4.30 ± 0.75 g.100 g-1) and vitamin C (14.74 ± 0.53 mg.100 g-1) stand out. The macroelement with the highest proportion corresponded to potassium (215.83 ± 11.72 and 98.41 ± 5.54 mg.100 g-1, for red and yellow pitahaya, respectively). This was followed by phosphorus (28.70 ± 0.28 and 17.99 ± 1.48 mg.100 g-1, for red and yellow pitahaya, respectively) and magnesium (29.88 ± 0.53 and 16.09 ± 2.80 mg.100 g-1, for red and yellow pitahaya, respectively). Regarding the content of microelements, the contents of manganese (5.48 ± 0.1 mg.kg-1) and zinc (5.39 ± 0.25 mg.kg-1) for red pitahaya stood out; and in the case of yellow pitahaya, the highest values corresponded to iron (21.07 ± 0.18 mg.kg-1) and manganese (7.49 ± 1.12 mg.kg-1). The study concluded that red and yellow pitahaya fruits represent an important source of fiber, minerals and vitamin C and they can be used for the benefit of human health and nutrition.
... Hasil analisis senyawa yang dilakukan Tanore et al. (2012) menemukan bahwa buah naga mengandung senyawa fenolik yang potensial digunakan sebagai antioksidan. Selain itu, kulit buah naga juga mengandung vitamin C, vitamin E, vitamin A, alkaloid, terpenoid, flavonoid, tiamin, niasin, piridoksin, kobalamin, fenolik, karoten, dan fitoalbumin yang diduga juga memiliki manfaat sebagai antioksidan (Jaafar et al., 2009). menghambat penyakit degeneratif seperti penyakit jantung, arteriosklerosis, kanker, dan gejala penuaan. ...
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ABSTRAK Penyakit degeneratif dapat timbul karena adanya kerusakan sel atau jaringan yang disebabkan oleh radikal bebas. Hal ini dapat dicegah dengan antioksidan alami seperti buah dan sayuran. Penelitian ini bertujuan untuk mengetahui potensi buah naga merah (Hylocereus polyrhizus) sebagai antioksidan. Melalui penelitian ini diharapkan dapat diketahui gambaran aktivitas antioksidan dan kondisi optimum reaksinya terhadap radikal bebas. Penelitian ini diawali dengan melakukan ekstraksi kulit buah menggunakan etanol. Selanjutnya dilakukan identifikasi senyawa melalui uji fitokimia untuk mengetahui kandungan senyawa aktif yang terdapat dalam ekstrak etanol. Uji antioksidan, dilakukan menggunakan DPPH (2,2-difenil-1-pikrilhidrazil) sebagai radikal bebas. Hasil uji fitokimia meunjukkan bahwa ekstrak kulit buah naga mengandung komponen fenolik yang potensial sebagai antioksidan. Dari pengujian menggunakan DPPH (2,2-difenil-1-pikrilhidrazil) menunjukkan bahwa ekstrak kulit buah naga memiliki aktivitas antioksidan dengan nilai IC50 sebesar 0,583 mg/mL. Kata kunci: buah naga merah (Hylocereus polyrhizus), antioksidan, DPPH (2,2-difenil-1-pikrilhidrazil) ABSTRACT Oxidative stress can cause oxidative damage from the level of cells, tissue, and organs. Oxidative stress can be overcome with natural antioxidants such as fruits and vegetables. The aim of this study was to identify active compounds by phytochemical screening and to further investigate the antioxidant properties on the peel of red dragon fruit (Hylocereus polyrhizus). Antioxidant activity was determined using DPPH (2,2-difenil-1-pikrilhidrazil) as radical. The result of phytochemical screening showed that the peel of dragon fruit extract has phenolic compounds. The DPPH radical scavenging antivity determination showed that the IC50 for the peel of dragon fruit extract was 0,583 mg/mL. The result suggested that the peel of dragon fruit extract has good activities as antioxidant.
... Since pitaya fruits are rich in vitamins, minerals, and an excellent source of antioxidants, their consumption has become widespread in different ways. The fruits of pitaya varieties with red flesh color contain betacyanin, which is known as an essential antioxidant pigment [7,8,9]. In addition to betacyanin, the flesh of red pitaya contains high amounts of vegetable albumin, vitamins, and water-soluble fiber [10]. ...
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Providing a thorough introduction to the core areas of food science specified by the Institute of Food Technologists, Introduction to Food Chemistry focuses on principles rather than commodities and balances facts with explanations. The text covers the major areas of food science, including food chemistry, food analysis and methods for quality assurance, nutrition, diet and health, food microbiology, food material science, biochemical changes in fresh foods, food enzymology, and food processing. Within each chapter, more complex ideas appear near the end. This provides beginning students and those new to the food industry with a complete spectrum of information, while assisting advanced students with specialized papers and research articles. This multi-level text presents a wealth of information in a clear and accessible style. It serves as an ideal introduction or supplementary textbook for undergraduate and graduate students in food science courses.
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Summary We tested the hypothesis that an optimum method of drying fruit could be designed. The effect of the method used for drying on colour of apple, banana, potato and carrot was investigated for five different methods of drying: conventional, vacuum, microwave, freeze and osmotic drying. Colour characteristics were studied by measuring lightness (L), redness (a) and yellowness (b) using a Hunter Lab chromatometer. The method used to dry the material was found to significantly affect the three colour parameters. The changes in redness (a) and yellowness (b) were found to follow a first order kinetic model. Air-, vacuum- and microwave-dried materials caused extensive browning in the fruits and vegetables, this was manifested by a significant drop of the L parameter and an increase of the a and b parameters. Osmotically pretreated samples did not brown as much as the untreated samples and the value for lightness (L) decreased only slightly while a and b increased slightly. Freeze drying seems to prevent colour changes, resulting in products with improved colour characteristics.
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The peel of Hylocereus polyrhizus is often regarded as a waste hence this study was aimed at exploring the feasibility of using the peel as a natural colorant using simple water extraction method. Samples were subjected to a series of temperatures: Room temperature (RT), 50, 80 and 100 degrees C; varied length of heating time from 1, 2, 3, 4, 5 and 10 min and a varied range of pH using 1 M of citric acid solution. The best condition to obtain highest betacyanin content was heating samples at 100 degrees C for 5 min in a pH 5 citric acid solution. The next part of this study involved the stability test of the pigments obtained through the best method determined earlier. The pigments were dried and resuspended in distilled water. The samples were then exposed to light to monitor pigment changes. Initial resuspension of the dried pigments yielded a comparable high content of betacyanins to its juice counterpart. The results showed that resuspended pigments had high pigment retention and were stable up to 7 days. These initial findings must be further studied in more controlled conditions to understand the stability of betacyanin. Nevertheless, the results show that betacyanin obtained from the peel of dragon fruit has a high potential to be used as a natural dye.