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.

PRELIMINARY STUDY ON THE EFFECT OF WATERMELON JUICE AND MILK SOLUTION ON DE-ADHESION, DEVELOPMENTAL STAGES AND HATCHING RATE OF EGGS AND SURVIVAL OF FRY OF CLARIAS GARIEPINUS

Sticky layer of Clarias gariepinus eggs cause the clumping of eggs immediately after fertilization, this create low oxygen, and increase pathogenic infection, thereby reducing fertilization and hatching rate hence reduces in mass production of C. gariepinus seed. Although various substances are use in the removal of the sticky layer, no information is available about the use of watermelon. Therefore, the present study, aim in exploring the potential of using watermelon in removing the sticky layer of C. gariepinus to enhance production. Fertilized eggs were treated with watermelon juice (T1) for comparison with 14 g L-1 milk solution (T2 as de-adhesion reference) and water as control (T0 as adhesion reference). The treatments were agitated with aeration for 30 minutes, rinsed with water, and poured on respective netted hatching trough, with water recirculation for incubation at 27 0C for 24 h period. Except for T0, no clumping of eggs was observed in the remaining groups. Slight variation in attaining a developmental stage among eggs was observed in eggs treated with watermelon. Hatching and survival rate in T2 are higher than T1 and T0 (P<0.05). However, watermelon indicated the potential, as it removed the sticky layer while maintaining hatching and survival rate as in the control (T0) (P>0.05), more should be explored before adoption of watermelon for de-adhesion and incubation of C. gariepinus eggs.

Effects of Blenderized Watermelon With the Rind on Satiety, Bowel Movement, and Postprandial Glucose

Objectives Many studies have examined the beneficial effects of watermelon flesh on metabolic diseases, yet fewer studies have investigated the effects of watermelon rind. While normally discarded, rind consumption not only reduces food waste but contains fiber (pectin) and healthful bioactive compounds such as citrulline. This study examined the effects of watermelon rind consumption on postprandial glucose, satiety and bowel movements. It was hypothesized that consumption of blenderized watermelon juice with rind would lower postprandial glucose, increase satiety and improve bowel movement habits. Methods In a double-blind randomized crossover study, 21 participants (age 26.3 ± 5.7 y, BMI 22.6 ± 2.8 kg/m2) consumed one cup (8 fl. oz) of blenderized watermelon juice with or without rind. A visual analogue scale was used to measure satiety at baseline, immediately after, 20, 40, 60 and 90 minutes post juice consumption. Blood glucose was measured at baseline, 20, 40, 60 and 90 minutes post juice consumption. Bowel movement questionnaires were administered two days before and after each trial. Results Both blenderized watermelon juices (with and without rind) increased satiety with more fullness in watermelon juice with rind (P &lt; 0.05). Watermelon juice with rind also stabilized blood glucose levels in comparison to watermelon juice (P &lt; 0.001). No significant differences between the two trials for bowel movements were found, but no evidence of constipation or discomfort was presented among the participants. Conclusions These results suggest that watermelon juice with rind has favorable effects on postprandial glucose and satiety levels but no effect on bowel movements. Therefore, further research into the benefits of watermelon rind is important and could offer potential clinical applications and disease prevention. Funding Sources NUTR 302L Advanced Nutrition Laboratory San Diego State University and National Watermelon Promotion Board (NWPB 19–20).

The Effectiveness of Young Coconut Water and Watermelon Juice in Reducing Blood Pressure

Background: Blood pressure is influenced by psychosocial (stress), genetic, age, gender, nutritional status, and lifestyle (diet, lack of fiber consumption, smoking, lack of physical activity). 30 ml of young coconut water contains 61 mg of potassium, 5.45 mg of sodium, and 1.3 mg of sugar, affecting blood pressure changes. Coconut water contains K minerals and is useful for lowering blood pressure. Whereaswatermelon contains anti-hypertensive content, namely sodium, beta carotene, and potassium. Watermelon is rich in water, amino acids, L-arginine, which can maintain healthy blood pressure. Aim: This study aims to determine the effect of young coconut water and watermelon juice on blood pressure in the 2013 nursing students of Respati University Yogyakarta. Methods: This type of research is a quasi-experimental design with a nonequivalent control group pre and post-test. The sample was taken by simple random sampling, namely the control group (18 respondents), the young coconut water group (18 respondents), and papaya juice (18 respondents). Data pre-posttest of each group was tested using Paired T-test. The comparison control-treatment group was tested using an independent-test. Results: The mean differences of systole and diastole pre-posttest blood pressure in the control group were -1.8 mmHg and -1.0 mmHg. The mean difference in systole blood pressure and the pre-posttest diastole of young coconut water groups were -3.1mmHg and -2.4 mmHg. The mean systole and diastole blood pressure in the pre-posttest watermelon juice group were -2.9 mmHg and -1.5 mmHg. The pre-posttest results of systole and diastole blood pressure analysis in the p-value control group were 0.100 and 0.450. The pre-post test results of systole and diastole blood pressure analysis of young coconut water groups gained p-value of 0.030 and 0.194. The pre-post test results of the juice watermelon group's systole and diastole blood pressure analysis gained p-value of 0.032 and 0.181. The posttest results of systole and diastole blood pressure analysis in the control group and young coconut water gained p-value of 0.014 and 0.157. The post-test results of the systole and diastole blood pressure analysis control group and juice watermelon gained p-value of 0.013 and 0.420. Conclusion: Consumption of young coconut water and watermelon juice affects systole blood pressure, but it does not affect diastole blood pressure in nursing students in 2013 in Respati University Yogyakarta. Keyword: Blood pressure, Coconut Water, Watermelon Juice