scholarly journals Comparative Study of the Effects of Drying Methods on Antioxidant Activity of Dried Strawberry (Fragaria Var. Camarosa)

2013 ◽  
Vol 2 (2) ◽  
pp. 92 ◽  
Author(s):  
Maritza Alonzo-Macías ◽  
Anaberta Cardador-Martínez ◽  
Sabah Mounir ◽  
Gerardo Montejano-Gaitán ◽  
Karim Allaf
Keyword(s):  
Antioxidant Activity ◽  
Steam Pressure ◽  
Saturated Steam ◽  
Drying Methods ◽  
Anthocyanin Content ◽  
Flavonoid Content ◽  
Hot Air Drying ◽  
Total Anthocyanin ◽  
Hot Air ◽  
Instant Controlled Pressure Drop

<p>Hot air drying (HAD), freeze-drying (FD), and swell-drying (SD, coupling instant controlled pressure drop, DIC, to standard hot air) were applied to strawberries (<em>Fragaria</em> var. Camarosa). The total phenol, total flavonoid, and total anthocyanin contentswere evaluated versusthe drying methods. The correlations between the bioactive compounds and antioxidant activity were investigated. The obtained results showed that the differences in phenol levels were no quite comparing the three drying techniques; however, great variations were reported for anthocyanin and flavonoid content.</p> A strong correlation between the antioxidant activity and anthocyanin content was found in SD strawberries. Also, it was observed that saturated steam pressure (P) of DIC texturing operation, had a significant effect on the studied parameters compared to the thermal holding time (t). The optimum conditions of DIC were P = 0.35 MPa for t = 10 s to obtain the highest levels of phenols, flavonoids, and anthocyanins, as well as antioxidant activity.

scholarly journals Effects of Drying Techniques on Murtilla Fruit Polyphenols and Antioxidant Activity

2014 ◽  
Vol 3 (5) ◽  
pp. 73 ◽  
Author(s):  
Susana Alfaro ◽  
Ana Mutis ◽  
Andres Quiroz ◽  
Ivette Seguel ◽  
Erick Scheuermann
Keyword(s):  
Antioxidant Activity ◽  
Freeze Drying ◽  
Anthocyanin Content ◽  
Hot Air Drying ◽  
Air Drying ◽  
Total Anthocyanin ◽  
Hot Air ◽  
Freeze Dried ◽  
Dried Fruit ◽  
Fruit Preservation

<p>‘Murtilla’ (<em>Ugni molinae</em> Turcz) is a native Chilean species that belongs to the Myrtaceae family. It produces a small, globular fruit with pleasant flavor and recognized antioxidant activity. Convective hot-air and freeze drying are important techniques for fruit preservation, but their effect on murtilla fruit polyphenols and antioxidant activity has not yet been studied simultaneously. The objective of this study was to compare the effect of convective hot-air drying at 65 and 80 ºC and freeze drying on total polyphenol content (TPC), total anthocyanin content (TAC), polyphenols and anthocyanins of the Red Pearl-INIA variety of fresh murtilla fruits as measured by HPLC and antioxidant activity (DPPH and ABTS). The freeze dried fruit retained higher values for TPC (2192.4 mg/100 g d.w.), TAC (13.4 mg/100 g d.w.), polyphenols (79.02 mg/100 g d.w. by HPLC) and anthocyanins (0.188 mg/100 g d.w. by HPLC) than the murtilla dried by convective hot-air at both 65 and 80 ºC. The application of all treatments showed a positive increase in the DPPH (2945.4 to 3677.6 ?mol TE/100 g d.w.) and ABTS (2664.8 to 3397.2 ?mol TE/100 g d.w.) antioxidant activity of the dried murtilla compared to the DPPH (2111.1 ?mol TE/100 g d.w.) and ABTS (2247.8 ?mol TE/100 g d.w.) of the fresh fruit. Freeze drying was the best technique for the retention of polyphenols and antioxidant activity from the fresh murtilla fruit. Therefore, freeze drying is recommended over convective hot-air drying at 65 and 80 ºC when these bioactive compounds need to be preserved.</p>

scholarly journals Effect of drying techniques on the retention of antioxidant activities of Saskatoon berries

2013 ◽  
Vol 2 (2) ◽  
Author(s):  
Pranabendu Mitra ◽  
Venkatesh Meda ◽  
Rick Green
Keyword(s):  
Antioxidant Activity ◽  
Radical Scavenging ◽  
Vacuum Drying ◽  
Anthocyanin Content ◽  
Dpph Radical ◽  
Total Anthocyanin ◽  
Hot Air ◽  
Total Anthocyanin Content ◽  
Dpph Radical Scavenging ◽  
Radical Scavenging Assay

The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.

scholarly journals Effect of drying techniques on the retention of antioxidant activities of Saskatoon berries

2013 ◽  
Vol 2 (2) ◽  
Author(s):  
Pranabendu Mitra ◽  
Venkatesh Meda ◽  
Rick Green
Keyword(s):  
Antioxidant Activity ◽  
Radical Scavenging ◽  
Vacuum Drying ◽  
Anthocyanin Content ◽  
Dpph Radical ◽  
Total Anthocyanin ◽  
Hot Air ◽  
Total Anthocyanin Content ◽  
Dpph Radical Scavenging ◽  
Radical Scavenging Assay

The main objective of this research was to compare the retention of antioxidant activity and total anthocyanin content of Saskatoon berries dried by freeze drying, microwave-vacuum drying, thin layer hot air drying and vacuum drying. Antioxidant activity of berry samples was determined by DPPH radical scavenging and ABTS radical scavenging, and the pH differential method was used to determine total anthocyanin content of the berry samples. The results showed that the freeze dried Saskatoon berries exhibited the highest retention of anthocyanin and antioxidant activity among the dried samples, followed by microwave-vacuum dried berries, thin layer hot air dried berries and vacuum dried berries. There were significant differences between the berry samples at P<0.05.  DPPH radical scavenging and ABTS radical scavenging were correlated linearly with an R2 value of 0.99 at P<0.05 showing their effectiveness for the determination of the antioxidant activity of the Saskatoon berries. However, the DPPH radical scavenging assay was more effective than the ABTS radical scavenging assay. The results also showed that antioxidant activity of the berries was highly correlated with the total anthocyanin content of the fruit. The reduction of anthocyanin in dried berry samples was linearly correlated with the reduction of DPPH radical scavenging with an R2 value of 0.97 at P<0.05 and, also, linearly correlated with the reduction of ABTS radical scavenging with an R2 value of 0.88 at P<0.05.

scholarly journals Impact of Instant Controlled Pressure Drop (DIC) Treatment on Drying Kinetics and Caffeine Extraction from Green Coffee Beans

2012 ◽  
Vol 1 (1) ◽  
pp. 24 ◽  
Author(s):  
I. Kamal ◽  
A. Gelicus ◽  
K. Allaf
Keyword(s):  
Pressure Drop ◽  
Initial Moisture Content ◽  
Effective Diffusivity ◽  
Steam Pressure ◽  
Raw Material ◽  
Saturated Steam ◽  
Drying Time ◽  
Hot Air ◽  
Instant Controlled Pressure Drop ◽  
The Impact

<p>The present work is directed towards the impacts of Détente InstantanéeContrôléeDIC (French, for instant controlled pressure-drop) in terms of decaffeination and drying of Ethiopian green coffee beans (GCBs).DICconsisted in subjecting the product to a high-pressure saturated steam during some seconds and ended with an abrupt pressure drop towards a vacuum. A conventional aqueous extraction and a hot air-drying took place after DIC treatment. Inthis study, Response Surface Method (RSM) was used withDIC saturated steam pressure P, thermal treatment time t, and initial moisture content W asthe independent variables. Both direct DICextract recovered from the vacuum tank and the aqueous extracts wereanalyzed and quantified using the reversed phase-HPLC. With decaffeination ratiosas dependent variables, P and Wwere the most significant operating parameters; whilet was much weaker.Total decaffeination ratio could reach 99.5% after DIC treatment at specificconditions of W=11.00% db, P=0.1 MPa, and t=35swhile it was only 58% when achieved with untreated raw material.</p> The effective diffusivity  and the starting accessibility  were calculated from the diffusion/surface interaction kinetic model of hotair drying after DIC treatment. They dramatically increased with P and t while W had a weak impact.Thus, at the optimized DICconditions, and  increased from 0.33 to 12.60 10<sup>-10</sup>m² s<sup>-1</sup>and from 0.75 to 11.53 g/100 g db, respectively. Drying time needed to reach 5% db became 60 min instead of 528 min for untreated raw material. <p>RSM analysis showed that the DIC saturated steam pressure P and the initial moisture content W were the most significant variables both affecting the decaffeination ratio; the impact of the total thermal processing time t was much weaker. Total decaffeination ratio could reach 99.5% after DIC treatment at specific conditions of W=11.00% db, P=0.1 MPa, and t=35 s while it was only 58% when achieved with untreated raw material.</p> <p>Using diffusion/surface interaction model of hot-air drying kinetics just after DIC treatment, we could observe that DIC expansion dramatically improved the drying kinetic parameters, with P and t as the most significant DIC operating parameters while the impact of W was much weaker. Thus, the optimized DIC treatment allowed the effective diffusivity  and the starting accessibility to increase from 0.33 10<sup>-10</sup> m² s<sup>-1</sup> and 0.75 g/100 g db to 12.60 10<sup>-10</sup> m² s<sup>-1</sup> and 11.53 g/100 g db, respectively. Drying time needed to reach 5% db became 60 min instead of 528 min for untreated raw material.</p>

scholarly journals Effect of Blanching on Enzyme Inactivation, Physicochemical Attributes and Antioxidant Capacity of Hot-Air Dried Pomegranate (Punica granatum L.) Arils (cv. Wonderful)

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 25
Author(s):  
Adegoke Olusesan Adetoro ◽  
Umezuruike Linus Opara ◽  
Olaniyi Amos Fawole
Keyword(s):  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Punica Granatum ◽  
Enzyme Inactivation ◽  
Soluble Solids ◽  
Anthocyanin Content ◽  
Hot Air Drying ◽  
Air Drying ◽  
Total Anthocyanin ◽  
Hot Air

Blanch-assisted hot-air drying of pomegranate arils with blanching treatments 90 °C for 30 s, 100 °C for 60 s, and unblanched (control) arils were investigated. Effects of blanching on enzyme inactivation (polyphenol oxidase and peroxidse), colour, texture, and other qualities of dried arils were discussed. The hot-air drying conditions were 60 °C, 19.6% relative humidity, and 1.0 m s−1 air velocity. Results showed that blanching reduced enzyme activity by 76% and 68% for blanched arils treated at 90 °C for 30 s and 100 °C for 60 s, respectively, compared to unblanched arils. With regard to the total colour difference (TCD), unblanched arils were 20.9% and 16.6% higher than blanched arils treated at 90 °C for 30 s and 100 °C for 60 s, respectively. Furthermore, the total soluble solids (TSS) for unblanched aril increased significantly from 16.1 to 24.9 °Brix after drying, followed by arils treated at 90 °C for 30 s and 100 °C for 60 s (21.4; 18.5 °Brix), respectively. Among the blanching treatments, dried arils treated at 90 °C for 30 s had the highest total anthocyanin content (28.6 mg C3gE/g DM), followed by 100 °C for 60 s (24.8 mg C3gE/g DM). Similarly, dried arils treated at 90 °C for 30 s had the highest radical scavenging activity (RSA) (32.1 mM TE/g DM) while the least was observed with unblanched arils (17.0 mM TE/g DM). Overall, the blanching treatment was more effective to maintain the quality attributes of pomegranate dried arils.

Improving Nutritional Value of Dried Blueberries (Vaccinium corymbosum L.) Combining Microwave-Vacuum, Hot-Air Drying and Freeze Drying Technologies

2008 ◽  
Vol 4 (5) ◽  
Author(s):  
Esteban I Mejia-Meza ◽  
Jaime A. Yanez ◽  
Neal M. Davies ◽  
Barbara Rasco ◽  
Frank Younce ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Nutritional Value ◽  
Freeze Drying ◽  
Vaccinium Corymbosum ◽  
Drying Methods ◽  
Hot Air Drying ◽  
Total Polyphenols ◽  
Air Drying ◽  
Hot Air ◽  
Freeze Dried

Blueberries (Vaccinium corymbosum L.) were dried combining microwave-vacuum, hot-air drying and freeze drying technologies to retain their nutritional value. Polyphenol retention, total polyphenols, anthocyanins, and antioxidant activity were evaluated in dried blueberries. Glycoside compounds for ellagic acid, quercetin, and kaempferol exhibited a higher retention than phloridzin, and R- and S-naringin in dried blueberries following dehydration. Freeze and HA-MIVAC® dried blueberries had a higher retention of total polyphenols and anthocyanins. Freeze dried blueberries had higher antioxidant activity, followed by the combination of HA-MIVAC®, MIVAC® and HA drying methods. FD, HA-MIVAC® and MIVAC® treated blueberries had a higher retention of individual polyphenols than HA treated blueberries, indicating that the nutritional properties of berries may be retained to a greater extent when these processes are employed.

scholarly journals Effect of Drying Methods on Bioactive Compounds and Antioxidant Capacity in Grape Skin Residues from the New Hybrid Variety “BRS Magna”

Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3701
Author(s):  
Gabriela Viana da Silva ◽  
Bruna Aparecida Souza Machado ◽  
Walkia Polliana de Oliveira ◽  
Camilla Fernanda Godinho da Silva ◽  
Cedenir Pereira de Quadros ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Bioactive Compounds ◽  
Radical Scavenging ◽  
Total Phenolic ◽  
Drying Methods ◽  
Anthocyanin Content ◽  
Drying Process ◽  
Total Anthocyanin ◽  
Antioxidant Power ◽  
Conventional Oven

The effects of the drying process using the conventional oven and freeze-drying on the thermogravimetric profile, proximate composition, color parameters, individual bioactive compounds, and antioxidant activity in the grape residue (skin) were evaluated. Twenty individual phenolic compounds were identified, where a variation in concentration was observed for flavonols, stilbenes, phenolic acids, flavonoids, procyanidins, and particularly anthocyanins (malvidin-3,5-di-O-glucoside of 253.2–536.9 mg/kg) due to the drying process. Drying in a conventional oven caused a decrease of 23% of the total polyphenols. The skin of the BRS magna grape has a high concentration of total phenolic content of 489.5–148.3 mg.GAE/100 g, total anthocyanin content of 124.9–260.1 mg.CE/100 g, and total flavonoid content of 12.7–26.0 mg.QE/100 g. The results of free radical scavenging activity (1.26–4.91 μg/mL, as EC50) and ferric reducing antioxidant power (82.93–184.10 μmol/g of skin as equivalent to Fe2SO4) indicate high antioxidant activity, independently of the drying process applied. It was concluded that, if the application is directed to anthocyanin compounds, the use of lyophilization is recommended. On the other hand, if the interest is in bioactive compounds that exert antioxidant activity, conventional oven-drying can be used.

scholarly journals Composition Changes in Lycium ruthenicum Fruit Dried by Different Methods

2021 ◽  
Vol 8 ◽  
Author(s):  
Youyuan Lu ◽  
Xiangfeng Kong ◽  
Juanhong Zhang ◽  
Chao Guo ◽  
Zhuo Qu ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Moisture Content ◽  
Shelf Life ◽  
Total Phenolic ◽  
Drying Methods ◽  
Hot Air Drying ◽  
Air Drying ◽  
Sun Drying ◽  
Hot Air ◽  
Lycium Ruthenicum

The fruit of Lycium ruthenicum (LRF), known as black wolfberry, is a medicinal and edible fruit. The fresh LRF is perishable and has only about 3 days of shelf life. Drying could prolong the shelf life of LRF. However, it could imply physical changes and chemical modification. This study evaluated the effect of sun drying (SD), hot air drying (HD), and freeze drying (FD) on the appearance characteristics, moisture content, bioactive compounds, amino acid composition, and antioxidant activity of LRF. The results showed that LRF dried by FD was round, expansive, fragile, and maintained the largest amount of appearance traits among the three drying methods. Drying methods had a significant effect on phytochemical content and antioxidant activity of LRF (P &lt; 0.05). Principal component analysis (PCA) showed that procyanidin content (PAC), asparagine (Asn), total phenolic content (TPC), total anthocyanin content (TAC), and moisture content were the main sources of the difference in LRF dried by different methods. The characteristic of LRF in FD was low moisture content, and high TPC, Asn, PAC, and TAC. Sun drying was opposite to FD. Hot air drying was high TPC and low TAC content. The quality of LRF was in the order of FD &gt; HD &gt; SD based on comprehensive evaluation of the phytochemical component content and antioxidant capacity. Additionally, the water temperature and soaking time had different antioxidant activity effect on LRF dried by different methods. These findings will provide useful information for production and utilization of LRF.

scholarly journals PEMANFAATAN LIMBAH KULIT BAWANG MERAH SEBAGAI KANDIDAT INGRIDIEN MINUMAN FUNGSIONAL ANTIOKSIDAN

2021 ◽  
Vol 12 (1) ◽  
pp. 39-52
Author(s):  
Rianita Pramitasari ◽  
Lidwina Krisna Chrysanti
Keyword(s):  
Antioxidant Activity ◽  
Citric Acid ◽  
Moisture Content ◽  
Water Activity ◽  
Total Phenolic ◽  
Drying Methods ◽  
Anthocyanin Content ◽  
Total Anthocyanin ◽  
Physical Test ◽  
Before And After

Shallot is widely used in culinary purpose. However, the use of shallot produces a lot of waste. Shallot skin contains anthocyanin, which has antioxidant activity. This study aimed to evaluate different solvents and extraction times for anthocyanin extraction from shallot skin, to evaluate different drying methods, and to evaluate the physicochemical properties of the anthocyanin powder. Chemical tests were conducted before and after drying, including total anthocyanin content, antioxidant activity using DPPH, total phenolic, and total flavonoid content. Physical tests were undertaken only after drying, including moisture content, water activity, viscosity, solubility, and colour. Extraction with citric acid solvent in 72h extract resulted in the highest total anthocyanin than water and acetic acid solvent. After drying, the highest total anthocyanin was obtained from foam mat drying method, which extracted using citric acid solvent. While antioxidant activity was not significantly differenced among samples. Physical test for the powders showed low moisture content and water activity, red colour index, as well as suitable viscosity and solubility results. In conclusion, anthocyanin powder from shallot skin has a potent as a functional antioxidant ingredient that can be applied in beverage products.

scholarly journals Effect of Processing Steps on Bioactive Compounds and Antioxidant Activities of High Anthocyanin Mulberry Fruit Powder

2021 ◽  
Vol 20 (2) ◽  
Author(s):  
Fuangfah Punthi ◽  
Somchai Jomduang
Keyword(s):  
Freeze Drying ◽  
Antioxidant Activities ◽  
Total Phenolic ◽  
Vacuum Drying ◽  
Drying Methods ◽  
Anthocyanin Content ◽  
Total Phenolic Compounds ◽  
Hot Air Drying ◽  
Hot Air ◽  
Mulberry Fruits

The objective of this research was to determine the amounts of bioactive compounds and antioxidant activities in each processing step in the production of high anthocyanin powder (HAP) from mulberry fruits to investigate suitable processing methods. For fresh mulberry fruits derived of Chiang Mai varieties, both in-season and off-season fruits had similar amounts of total anthocyanin content (TAC) and total phenolic compounds (TPC). In-season mulberry fruits had the highest potential to be used as a raw material for further study because of high antioxidant activities, large fruit size, and high productivity. Two methods of HAP production were tested. The first method used whole fruit drying with different drying methods included hot air drying (HAD), vacuum drying (VD), and freeze drying (FD). Hot air drying at 50, 60 and 70°C showed a decreased concentration of anthocyanins, which were 60% lower than that of fresh fruits. Vacuum drying at 55 and 75°C could provide high anthocyanin content and was similar to freeze drying, which had 87–97% anthocyanin retention. Vacuum drying at 75°C was most suitable for HAP production because of the short drying time (22.3 ± 0.4 hours), high anthocyanin retention (87.21%), high phenolic compound content, and high antioxidant activities. The second method used fermented and concentrated mulberry juice. This process used the following steps: yeast fermentation to decrease the sugar content, filtration to get rid of solid parts, evaporation to concentrate the solution, drying with different drying methods (vacuum drying and freeze drying), and crushing to powder. Throughout fermentation, filtration, and evaporation, high phenolic compound content and antioxidant activities were observed and 77.29% of anthocyanins were retained. However, these values decreased dramatically after the drying step. Therefore, drying the concentrated solution was not effective for HAP production. Of the processing methods tested, directly drying whole mulberry fruits with VD at 75°C was most suitable for HAP production. This method provided 13.06% ± 0.35 production yield of HAP, contained 13.51±0.08 mg/g DW of total anthocyanins, and 27.47 ± 0.50 mg GAE/g DW of total phenolic compounds. Additionally, the antioxidant activities by DPPH, TRAP, and TEAC assays were 2.91 ± 0.19, 16.22 ± 0.31, and 22.34 ± 0.29 mmol GAE/g DW, respectively.

Sign in / Sign up

Export Citation Format

Share Document