Effect of Storage Temperatures on Physico-Chemicals, Phytochemicals and Antioxidant Properties of Watermelon Juice (Citrullus lanatus)

Watermelon (Citrullus lanatus) consists of high moisture content and is favoured for its juice products. The popular fruit has a tempting taste, sweet aroma and attractive flesh colour. It is enriched with phytochemicals and antioxidant properties that are beneficial to human health. Due to convenience, the majority of individuals are likely to consume watermelon juice. However, little is known about the fruit juice storage and temperatures that may affect its beneficial properties. This study investigated the effect of storage temperature at room temperature, refrigerator cold, refrigerator freeze and freeze-dried, and analyzed the juice physico-chemicals (weight loss, pH, ash, moisture, total soluble solid, browning and turbidity), phytochemicals (total phenolic, total flavonoid, lycopene and β-carotene) and antioxidant scavenging activities during 9 days of storage. The results showed that watermelon juice was affected by storage temperatures and conditions with significant changes in physico-chemical appearance and decrease in total phytochemical content, thus consequently affecting their antioxidant activities during 9 days of storage. Although fresh watermelon juice can be consumed for its high nutritional values, freeze-drying is the preferable technique to retain its benefits and to delay juice degradation.

ANALISIS KADAR POLIFENOL DAN AKTIVITAS ANTIOKSIDAN YANG TERDAPAT PADA EKSTRAK BUAH : STUDI KEPUSTAKAAN

ABSTRACTPolyphenols are one of the largest categories of phytochemicals and are the most widely distributed among various types of plants and fruits. Polyphenols can also inhibit, prevent, and reduce oxidation by free radicals, which are good for health. Analysis of polyphenol content starts from the sample preparation process which includes the extraction of solid and liquid samples. The types of solvents commonly used for extraction are ethanol, methanol, and acetone. Furthermore, the analysis of polyphenol levels uses the Folin-Ciocalteau analysis method. The results of the review show that ripe bisbul fruit extract (Diospyros blancoi A. DC.) which was extracted using ethanol as a solvent had the highest polyphenol content and yield of several fruit extracts reported in this review. Meanwhile, the extract of green grapes (Vitis vinifera Linn. Var. Chinsiang) which was extracted using ethanol as a solvent had the lowest levels and yields of polyphenols. The highest antioxidant activity was shown by samples of red dragon fruit extract (Hylocereus polyrhizus (f.a.c weber) britton & rose). Meanwhile, the lowest antioxidant activity was shown by samples of Watermelon (Citrullus lanatus) fruit extract.Keywords: Pholyphenol, Extracts, Solvents, Folin CiocalteauABSTRAKPolifenol adalah salah satu kategori terbesar dari fitokimia yang paling banyak penyebarannya diantara berbagai jenis tanaman dan buah-buahan. Polifenol juga dapat menghambat, mencegah, mengurangi oksidasi oleh radikal bebas sehingga baik untuk kesehatan. Analisis kadar polifenol dimulai dari proses preparasi sampel yang meliputi ekstrasi sampel padat dan ekstraksi sampel cair. Jenis pelarut yang umum digunakan saat pengekstrakan yaitu etanol, metanol, dan aseton. Selanjutnya analisis kadar polifenol menggunakan metode analisis folin ciocalteau. Hasil review menunjukkan Ekstrak buah bisbul matang (Diospyros blancoi A. DC.) yang diekstrak menggunakan pelarut etanol memiliki kadar dan rendemen polifenol yang tertinggi dari beberapa ekstrak buah yang dilaporkan dalam review ini. Sedangkan ekstrak buah anggur hijau (Vitis vinifera Linn. Var. Chinsiang) yang diekstrak menggunakan pelarut etanol memiliki kadar dan rendemen polifenol yang terendah. Aktivitas antioksidan yang tertinggi ditunjukkan oleh sampel ekstrak buah naga Merah (Hylocereus polyrhizus (f.a.c weber) britton & rose) dibandingkan sampel lain dalam review ini. Sedangkan aktivitas antioksidan yang terendah ditunjukkan oleh sampel ekstrak buah Semangka (Citrullus lanatus) dibandingkan sampel lain dalam review ini.Kata kunci: Polifenol, ekstraksi, pelarut, folin ciocalteau

Dietary Inclusion of Citrullus lanatus Seed in Fish Feed: Proximate Analysis, Growth Performance and Feed Utilization in Clarias gariepinus Fingerlings

One of the factors militating against fish farming in Nigeria have been lack of adequate feed that are formulated to meet the nutrient requirement of culturable fish species. To this end, the study on dietary inclusion of Citrullus lanatus (watermelon) seed in fish feed: the proximate analysis, determination of growth performance and feed utilization in Clarias gariepinus fingerlings was carried out between August and October 2019. The proximate analysis and economic viability were determined according to standard methods. The experimental diet was set up across varying proportions: 0% as the control, 15%, 20%, 25% and 36% inclusion levels respectively. The result of the proximate analysis for the experimental diets showed that diet 3 (20.00% inclusion) had the highest crude protein content; lipid level was highest in diet 4 (25% inclusion); while diet 1 (control) had the highest dry matter, ash and nitrogen free extract contents. The result of the experiment showed that 36% watermelon seed inclusion yielded the highest growth performance and feed utilization in Clarias gariepinus fingerlings. However, there was no significant difference (P > 0.05) in relation to inclusion percentages of watermelon seed on growth performance in Clarias gariepinus fingerlings. In conclusion, relatively high proportion of watermelon seed inclusion in fish feed formulation is hereby recommended in order to improve growth performance and feed utilization in Clarias gariepinus fingerlings.

IDENTIFICATION OF SOME ROOTSTOCKS FOR WATERMELON CULTURES FROM ROMANIA

Among the grafting aims are (1) to enhance plant growth, fruit yield and quality; (2) to control wilt caused by pathogens; (3) to reduce viral, fungal and bacterial infection; (4) to strengthen tolerance to thermal or saline stress; (5) to increase nutrient and mineral uptake to the shoot. The cultivars used to obtain of grafted seedlings were from the Baronesa F1 (Citrullus lanatus) hybrid scion and the Pelops F1 (Lagenaria siceraria), Kiwano (Cucumis metuliferus) and Zefir (Benicasa hispida) rootstocks. The rootstock has influenced the number of fruits per plant, weight/fruit and production/plant; the Pelops rootstock has had a positive influence and the Kiwano and Zefir rootstocks have had a negative influence compared to the non-grafted variant. The Pelops rootstock (105.84 t/ha) has had a positive influence and the Kiwano rootstock (53.45 t/ha) and Zefir rootstock (51.38 t/ha) have had have a negative influence compared to the non-grafted variant (95.5 t/ha). The biometric measurements on watermelon fruit yield were made in 2020 year. The experience aimed the identification of some rootstocks for the watermelon cultures from Romania. The research shows that the rootstocks has influenced fruit yield and some grafting combinations researched may be recommended for cropping in Romania.

Effects of addition of Sodium Benzoate of the Physicochemical Characteristic of Watermelon rind (Citrullus lanatus)

Watermelon rind is a food product that utilize wasted albedo waste. Generally, jam is gel or semi-dense so it has short shelf life. To make the jam more imperishable in storage, preservatives can be added in manufactured progress, one of the preservatives that can be used is sodium benzoate. This research aims to determine the effects of the addition of sodium benzoate on the physicochemical characteristics of watermelon rind jam. The results reveals that the formula of watermelon rind jam with the addition of sodium benzoate has physicochemical content that not much different apart from the one that isn’t added by sodium benzoate. The characteristics that were significantly different were only in viscosity, the jam with the addition of sodium benzoate (6400 cP) was greater than the jam without the addition of sodium benzoate (2900 cP). The selected formula will be tested by organoleptic (hedonic quality) with texture, taste, and aroma attributes with the results that the jam formula was well received by 30 panelists. The quality of watermelon rind jam is identified by color aspect with average score of 5.10 with good category that has brownish yellow color, by texture with average score of 5.10 with good category that has soft and fibrous textured, and by the taste with average score of 5,20 with good category that has sweet acidity taste. Keywords: Watermelon rinds, sensorics analysis

INFLUENCIA DEL ACOLCHADO DE PLÁSTICO DE COLOR Y MANTA TÉRMICA EN SANDÍA CV. ‘SANTA AMELIA’ (Citrullus lanatus Thunb.)

El alcance del estudio se basó en analizar la productividad, calidad y precocidad del cultivo de sandía cv. ‘Santa Amelia’. El estudio se realizó en la costa central usando acolchado de polipropileno de diferentes tonalidades utilizando la manta térmica en ciertos tratamientos. Se estudió ocho tratamientos, acolchados de color blanco, negro y trasparente, en combinación con manta térmica, manta térmica sola y testigo. Se empleó el Diseño de Bloques Completamente Randomizado. Los resultados mostraron en una producción superior al usarse solamente acolchados y acolchados más manta térmica: Acolchado negro más manta térmica con 81,37; acolchado blanco con 75,95; acolchado trasparente 74,53 y acolchado negro 74,45 T*ha respectivamente muy superiores al testigo con 45,27 Tn*ha. Con respecto a la precocidad de la cosecha el tratamiento con acolchado negro en su primera cosecha logró el 34,75 %, resultado similar al a los que se les aplicó acolchado solo y en combinación con manta térmica, superando al tratamiento con solo manta térmica con 17,38% y testigo con 5,1% respectivamente. Respecto al factor del fruto largo sobre ancho, siendo el fruto más largo cuando el factor es mayor, los acolchados combinados con manta térmica obtuvieron el primer lugar estadísticamente que son el acolchado negro, blanco y trasparente en combinación con manta térmica con resultado de 1,36; 1,34 y 1,31 respectivamente. El uso de acolchado y manta térmica elevó la producción, calidad y concentración de cosecha por la elevación de la temperatura interna del suelo.

REVEALED COMPARATIVE ADVANTAGE OF WATERMELON TRADE IN ASEAN 5 COUNTRIES

Watermelon Citrullus Lanatus (Thunb) is an important commercial fruit crop in ASEAN. One way to improve economic growth is through trade and comparative advantage. There are very some researches regarding with comparative advantage of watermelon trade in ASEAN. The purpose of this article is to determine the comparative advantage of watermelon trade in five ASEAN member countries. This article uses secondary data only. Watermelon trade data covering the six years period 2014-2019 were obtained from the United Nations Commodity Trade Statistics Database. This article applies the original index of the revealed comparative advantage (RCA) and revealed symmetric comparative advantage (RSCA) to find out the level of comparative advantage of watermelon commodity. Results show that Lao Peoples Democratic Republic, Myanmar and Viet Nam have a comparative advantage of watermelon trade in the global market. This study suggests that ASEAN 5 member nations should try to maintain its comparative advantage of watermelon exports in the international market.