METHODS: This study compares the effects of spray drying, freeze drying, drum drying, vacuum oven drying, and convection oven drying on the physicochemical properties of Bintangor orange powder, including vitamin C and total carotenoid content. The physicochemical properties analyzed for the powders were color analysis, moisture content, water activity, hygroscopicity, degree of caking, wettability, flowability, water solubility index, and bulk density.
RESULTS: Our results showed that freeze dried and convection oven dried powders retained their color so that the powder was the same as the original puree. All powders used in this showed an acceptable moisture content level, with a range of 2.11–2.31%. Spray dried and drum dried powders had the lowest value of moisture content and water activity. Moreover, spray dried powders showed the lowest value in hygroscopicity and bulk density and took the shortest time to wet the powder. The highest solubility and flowability properties were 12.99%, 0.39 g/mL, 18.39 s, 96.08%, and 19.17°, respectively. However, the freeze drying method retained the highest value for both nutritional pigments of vitamin C and total carotenoid content, 18.31 mg/g and 91.32 μg/g, respectively.
CONCLUSIONS: Freeze drying is the most suitable drying method with favorable powder properties compared to spray drying, drum drying, vacuum oven drying and convection oven drying.
METHODS: The kedondong powder was dried using five methods: convection oven drying, vacuum drying, spray drying, drum drying and freeze drying. The physical properties, flowability and DPPH radical scavenging ability of dried kedondong powder were examined.
RESULTS: Spray-dried powder provided the significantly (p ≤ 0.05) highest process yield, which was 54.93%. All the powder produced had a low moisture content (3.03 to 5.66%) and water activity (0.19–0.37). Visually, whitish and fine powders were observed on spray-dried and freeze-dried samples, while convection oven-dried and vacuum-dried powder appeared yellowish and coarse. The pH of the reconstituted powders varied from 2.71 to 2.83, where drum-dried powder was the most acidic. Spray-dried powder showed the highest wettability and shortest dissolution time, which was 172.65 s and 10.55 s, respectively. With the exception of drum-dried powder, all the dried powders were classified as non-caking powders. The bulk and tapped density of the powders ranged from 0.32 to 0.70 g/mL and 0.38 to 0.86 g/mL, respectively. Vacuum-dried powder had very good flowability, convection oven-dried and drum-dried powder had good flowability, while spray-dried and drum-dried powder had fair flowability. Antioxidant assay showed that freeze-dried powder exhibited the highest free radical scavenging activity (IC50 = 701.29 μg/mL).
CONCLUSIONS: This study indicates that spray-dried kedondong powder has great potential in the food industry due to its high process yield and better powder quality. Meanwhile, freeze drying best preserved the antioxidant properties of the powder, which could potentially be used as a functional ingredient as a result. This study is important for the fruit processing industry as it offers an alternative for the farmer to produce kedondong fruit powder because the fruit has a short shelf life. Converting the fruit into powder can diversify the resulting produce into different applications, such as fruit juice, beverages, jam and other food products.
METHODS: The dengue infection in mouse model was established by inoculation of non-mouse adapted New Guinea C strain dengue virus (DEN-2) in AG129 mice. The freeze-dried CPLJ compounds were identified by Ultra-High Performance Liquid Chromatography High Resolution Accurate Mass Spectrometry analysis. The infected AG129 mice were orally treated with 500 mg/kg/day and 1000 mg/kg/day of freeze-dried CPLJ, starting on day 1 post infection for 3 consecutive days. The blood samples were collected from submandibular vein for plasma NS1 assay and quantitation of viral RNA level by quantitative reverse transcription PCR.
RESULTS: The AG129 mice infected with dengue virus showed marked increase in the production of plasma NS1, which was detectable on day 1 post infection, peaked on day 3 post-infection and started to decline from day 5 post infection. The infection also caused splenomegaly. Twenty-four compounds were identified in the freeze-dried CPLJ. Oral treatment with 500 mg/kg/day and 1000 mg/kg/day of freeze-dried CPLJ did not affect the plasma NS1 and dengue viral RNA levels. However, the morbidity level of infected AG129 mice were slightly decreased when treated with freeze-dried CPLJ.
CONCLUSION: Oral treatment of 500 mg/kg/day and 1000 mg/kg/day of freeze-dried CPLJ at the onset of viremia did not affect the plasma NS1 and viral RNA levels in AG129 mice infected with non-mouse adapted New Guinea C strain dengue virus.
METHODS: The AG129 mice were fed orally with FCPLJ for 3 consecutive days after 24 h of dengue virus inoculation. Plasma cytokines were screened by using ProcartaPlex immunoassay. The gene expression in the liver was analyzed by using RT2 Profiler PCR Array.
RESULTS: The results showed that FCPLJ treatment has increased the plasma CCL2/MCP-1 level during peak of viremia. Gene expression study has identified 8 inflammatory cytokine genes which were downregulated in the liver of infected AG129 mice treated with FCPLJ. The downregulated inflammatory cytokine genes were CCL6/MRP-1, CCL8/MCP-2, CCL12/MCP-5, CCL17/TARC, IL1R1, IL1RN/IL1Ra, NAMPT/PBEF1 and PF4/CXCL4.
CONCLUSION: The findings indicated the possible immunomodulatory role of FCPLJ during dengue virus infection in AG129 mice.
RESULTS: In most cases except for oven drying, the bulk density decreased, thus increasing the porosity. This might be attributed to the increase in the inter-particle voids of smaller sized particles with larger contact surface areas per unit volume. The current study revealed that oven-dried gum and freeze-dried gum had the highest and lowest compressibility index, thus indicating the weakest and strongest flowability among all samples. In the present work, the freeze-dried gum showed the lowest angle of repose, bulk, tapped and true density. This indicates the highest porosity degree of freeze dried gum among dried seed gums. It also exhibited the highest solubility, and foaming capacity thus providing the most desirable functional properties and flow characteristics among all drying techniques.
CONCLUSION: The present study revealed that freeze drying among all drying techniques provided the most desirable functional properties and flow characteristics for durian seed gum.