2,472 research outputs found

    Ultrasound increases the aqueous extraction of phenolic compounds with high antioxidant activity from olive pomace

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    Olive pomace is a waste produced by the olive oil industry in massive quantities each year. Disposal of olive pomace is difficult due to high concentrations of phenolic compounds, which is an environmental concern. However, phenolic compounds have applications in the health industry. Therefore, extraction of phenolic compounds from olive pomace has the potential to remove an environmentally hazardous portion of pomace while creating an additional source of income for farmers and producers. Using advanced technologies including Ultrasound Assisted Extraction (UAE), combined with water as an extraction solvent, has recently gained popularity. The present study outlines the optimal UAE conditions for the extraction of phenolic compounds with high antioxidant activity from olive pomace. Optimal conditions were developed using RSM for parameters power, time and sample-to-solvent ratio. Total phenolic compounds determined by Folin Ciocalteu method and total major bioactive compounds determined by HPLC as well as antioxidant capacity (DPPH and CUPRAC) were investigated. The optimal conditions for the extraction of phenolic compounds with high antioxidant activity were 2 g of dried pomace/100 mL of water at 250 W power for 75 min. UAE improved the extraction efficiency of water and yielded extracts with high levels of phenolic compounds and strong antioxidant activity

    System and method for transferring telemetry data between a ground station and a control center

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    Disclosed herein are systems, computer-implemented methods, and tangible computer-readable media for coordinating communications between a ground station, a control center, and a spacecraft. The method receives a call to a simple, unified application programmer interface implementing communications protocols related to outer space, when instruction relates to receiving a command at the control center for the ground station generate an abstract message by agreeing upon a format for each type of abstract message with the ground station and using a set of message definitions to configure the command in the agreed upon format, encode the abstract message to generate an encoded message, and transfer the encoded message to the ground station, and perform similar actions when the instruction relates to receiving a second command as a second encoded message at the ground station from the control center and when the determined instruction type relates to transmitting information to the control center

    Physical, barrier, and antioxidant properties of pea starch-guar gum biocomposite edible films by Incorporation of natural plant extracts

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    Active food packaging based on pea starch and guar gum (PSGG) films containing natural antioxidants (NAs) was developed. Four kinds of NAs (epigallocatechin gallate (EGCG), blueberry ash (BBA) fruit extract, macadamia (MAC) peel extract, and banana (BAN) peel extract) were added into the PSGG-based films as antioxidant additive. The effects of these compounds at different amounts on the physical and antioxidant characteristics of the PSGG film were investigated. The antioxidant activity was calculated with three analytical assays: DPPH radical scavenging ability assay, cupric reducing antioxidant capacity (CUPRAC), and ferric reducing activity power (FRAP). EGCG-PSGG films showed higher antioxidant activity, followed by BBA-PSGG, MAC-PSGG, and BAN-PSGG films, at all concentrations (0.75–3 mg/mL) and with all procedures tested. Additionally, the antioxidant activity of films showed a concentration dependency. The results revealed that addition of NAs made the PSGG film darker and less transparent. However, the moisture barrier was significantly improved when NAs were incorporated into the film. The FTIR spectra were examined to determine the interactions between polymers and NAs. The results suggested that incorporation of EGCG, BBA, MAC, and BAN into PSGG films have great potential for use as active food packaging for food preservation

    Development and application of rice starch based edible coating to improve the postharvest storage potential and quality of plum fruit (<i>Prunus salicina</i>)

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    The study investigated the possibility of enhancing the shelf life of plum fruit coated with rice starch-ι-carrageenan (RS-ι-car) composite coating blended with sucrose fatty acid esters (FAEs). Film solution (starch 3%, carrageenan 1.5% and FAEs 2%) was prepared by mixing the ingredients and properties of stand-alone films (physical, mechanical, barrier and surface morphology) were studied before applying the coating on fruit surface. Fruit were stored at 20 °C for 3 weeks and analyzed for weight loss, ethylene production, respiration rate, color change, firmness, and titratable acidity (TA) and soluble solid content (SSC). Surface morphology of stand-alone film and fruit surface (after applying on the plum fruit) was studied using scanning electron microscopy (SEM). Phytochemical analysis was performed during the storage period and total phenolic content (TPC), total antioxidant capacity (TAC), flavonoid content (FC) and free radical scavenging activity were determined. The rice starch composite coating was shown to be effective in reducing both weight loss (WL) and respiration rate and inhibiting the endogenous ethylene production when compared to the uncoated control fruit stored at room temperature (p &lt; 0.05). TPC, TAC, FC and free radical scavenging activity was unaffected in the coated fruit throughout the storage period (p &lt; 0.05). The findings reported in this study indicate that the RS-ι-car-FAEs coating prolongs the shelf life and maintains the overall quality of plum fruit during storage and could potentially be commercialized as a new edible coating for the plum fruit industry

    Effect of low-pressure storage on the quality of green capsicums (<i>Capsicum annum L.</i>)

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    Green capsicums (Capsicum annum L.) were stored under low pressure (4 kPa) at 10°C for 5 and 11 days with 100% RH. The results showed that the incidence of stem decay under low pressure storage for 5 and 11 days and storage at ambient atmosphere at 20°C for three days lower compared to fruits that were stored at regular atmosphere at 10°C. Fruit that had been stored at low pressure at 10°C had no symptoms of flesh rots for up to 11 days, whilst fruit which had been stored at regular atmosphere at 10°C had 6% flesh rots after 11 days storage at 10°C.There was no difference in flesh firmness and colour retention between fruits stored at low pressure and regular pressure at 10°C. Capsicums stored at low pressure had higher overall acceptability compared to fruit that were stored at regular atmosphere at 10°C. These results demonstrate the potential of low pressure storage as an effective technique to manage capsicum fruit quality, however there was no additional benefit when fruits were stored at low pressure for more than 5 days

    Encapsulation of citrus by-product extracts by spray-drying and freeze-drying using combinations of maltodextrin with soybean protein and ι-carrageenan

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    The effect of different combinations of maltodextrin (MD) coating agents (MD, MD + soybean protein, and MD + ι-carrageenan) on the encapsulation of lemon by-product aqueous extracts using freeze-drying and spray-drying were investigated. The total phenolic content (TPC), total flavonoid content (TFC), and ferric ion reducing antioxidant power (FRAP) of the microparticles were evaluated. Freeze-drying with the mixture of MD + soybean protein resulted in the highest retention of TPC, TFC, and FRAP (1.66 ± 0.02 mg GAE/g d.b., 0.43 ± 0.02 mg CE/g d.b., and 3.70 ± 0.05 mM TE/g, respectively). Freeze-drying resulted in microparticles with lower moisture content (MC) and water activity (aw) than those produced by spray-drying. Specifically, the MC and aw of the microparticles produced by freeze-drying ranged from 1.15 to 2.15% and 0.13 to 0.14, respectively, while the MC and aw of the microparticles produced by spray-drying ranged from 6.06% to 6.60% and 0.33 to 0.40, respectively. Scanning electron microscopy revealed that spray-drying resulted in the formation of spherical particles of different sizes regardless of the type of coating agent. Although freeze-drying resulted in microparticles with amorphous glassy shapes, the mixture of MD + soybean protein resulted in the formation of spherical porous particles. X-ray diffraction revealed a low degree of crystallinity for the samples produced by both techniques.</p
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