Determination of Antioxidant Activity of Edible Calendula Flowers by Hot-air Drying Time

2018 ◽  
Vol 26 (4) ◽  
pp. 202-208
Author(s):  
Sang Im Oh ◽  
Seo Young Kim ◽  
Ja Hee Lee ◽  
Ae Kyung Lee
Keyword(s):  
Antioxidant Activity ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Hot Air

Effects of drying methods on color retention and chlorophyll of celery (ApiumgraveolensL.), spinach (Spinacia oleraceaL.), Malabar spinach (Basella albaL.)

2020 ◽  
pp. 53-61
Author(s):  
Dat Q Tran
Keyword(s):  
Microwave Drying ◽  
Drying Methods ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Color Retention ◽  
Hot Air ◽  
Drying Techniques ◽  
Dried Vegetables

Dried vegetables are considered convenient for storage, transportation and preservation. The different drying techniques could influence the quality of resulting products. This study aimed to evaluate the effects of three distinguish drying methods as hot-air drying, foam-mat drying and microwave drying on the color retention and chlorophyll of green vegetables powder. Fresh spinach(Spinacia oleraceaL.), celery (Apium graveolensL.), Malabar spinach (Basella albaL.) were dried by different methods: hot air at 60oC, foam-mat at 60oC and microwave at 270 W until the samples reached approximately 9% of moisture content (wb). The drying time of the dried samples by microwave, foam-mat and hot-air method were 60, 210 and 240 min, respectively. Foam-mat dried vegetables were found to have the best quality in terms of color and the residual chlorophyll content. The findings suggest that foam-mat drying is promising in dried vegetable processing

scholarly journals Effects of Freeze Vacuum Drying Combined with Hot Air Drying on the Sensory Quality, Active Components, Moisture Mobility, Odors, and Microstructure of Kiwifruits

2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Lihui Zhang ◽  
Yu Qiao ◽  
Chao Wang ◽  
Li Liao ◽  
Lu Liu ◽  
...  
Keyword(s):  
Sensory Quality ◽  
Antioxidant Properties ◽  
Bound Water ◽  
Principal Component ◽  
Vacuum Drying ◽  
Active Components ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Hot Air

In this study, freeze vacuum drying (FVD), hot air drying (AD), and FVD combined with AD (FVD-AD) were used to dry kiwifruits. Dried products were analyzed comprehensively on their sensory quality, active components, moisture mobility, odors, and microstructure. Results showed that the FVD-AD saved time by 38.22% compared with FVD while maintaining an acceptable product quality. The antioxidant properties of FVD-AD were lower than those of FVD but significantly higher than those of AD. Moreover, compared with FVD products, FVD-AD products were moderately hard (5252.71 ± 33.53 g) and improved in color, bound water, and microstructure. Additionally, FVD-AD consumed lesser drying time and energy than FD. According to cluster analysis, the odors of FVD-AD products were similar to those of the fresh ones. Principal component analysis of physicochemical and drying cost indicated that FVD-AD was a promising processing technique for functional kiwifruit snacks.

Quality Characterization of Waste Olive Cake During Hot Air Drying: Nutritional Aspects and Antioxidant Activity

2012 ◽  
Vol 6 (5) ◽  
pp. 1207-1217 ◽  
Author(s):  
Elsa Uribe ◽  
Roberto Lemus-Mondaca ◽  
Antonio Vega-Gálvez ◽  
Lorena A. López ◽  
Karina Pereira ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Olive Cake ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air

scholarly journals The Effect of Different Extraction Protocols on Brassica oleracea var. acephala Antioxidant Activity, Bioactive Compounds, and Sugar Profile

Plants ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 1792
Author(s):  
Nikola Major ◽  
Bernard Prekalj ◽  
Josipa Perković ◽  
Dean Ban ◽  
Zoran Užila ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Freeze Drying ◽  
High Energy ◽  
Total Phenolic ◽  
Glucosinolate Content ◽  
Aqueous Methanol ◽  
Hot Air Drying ◽  
Air Drying ◽  
Hot Air ◽  
Sugar Profile

The extraction of glucosinolates in boiling aqueous methanol from freeze dried leaf tissues is the most common method for myrosinase inactivation but can be hazardous because of methanol toxicity. Although freeze drying is the best dehydration method in terms of nutritional quality preservation, the main drawbacks are a limited sample quantity that can be processed simultaneously, a long processing time, and high energy consumption. Therefore, the aim of this study is to evaluate the effects of applying high temperature for myrosinase inactivation via hot air drying prior to the extraction step, as well as the effects of cold aqueous methanol extraction on total antioxidant activity, total glucosinolates, total phenolic content, and sugar profile in 36 landraces of kale. The results from our study indicate that cold aqueous methanol can be used instead of boiling aqueous methanol with no adverse effects on total glucosinolate content. Our results also show that hot air drying, compared to freeze drying, followed by cold extraction has an adverse effect on antioxidant activity measured by DPPH radical scavenging, total glucosinolate content, as well as on the content of all investigated sugars.

scholarly journals Influence of Different Hot Air Drying Temperatures on Drying Kinetics, Shrinkage, and Colour of Persimmon Slices

Foods ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 101 ◽  
Author(s):  
Senadeera ◽  
Adiletta ◽  
Önal ◽  
Di Matteo ◽  
Russo
Keyword(s):  
Moisture Content ◽  
Quadratic Model ◽  
Drying Process ◽  
Air Velocity ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Drying Characteristics ◽  
Drying Temperature ◽  
Hot Air

Drying characteristics of persimmon, cv. “Rojo Brillante”, slabs were experimentally determined in a hot air convective drier at drying temperatures of 45, 50, 55, 60, and 65 °C at a fixed air velocity of 2.3 m/s. It was observed that the drying temperature affected the drying time, shrinkage, and colour. Four empirical mathematical models namely, Enderson and Pabis, Page, Logarithmic, and Two term, were evaluated in order to deeply understand the drying process (moisture ratio). The Page model described the best representation of the experimental drying data at all investigated temperatures (45, 50, 55, 60, 65 °C). According to the evaluation of the shrinkage models, the Quadratic model provided the best representation of the volumetric shrinkage of persimmons as a function of moisture content. Overall, higher drying temperature (65 °C) improved the colour retention of dried persimmon slabs.

A Comparative Study of Combined Microwave Techniques for Longan (Dimocarpus longan Lour.) Drying with Hot Air or Vacuum

2017 ◽  
Vol 13 (7) ◽  
Author(s):  
Krit Apinyavisit ◽  
Adisak Nathakaranakule ◽  
Somchart Soponronnarit ◽  
Gauri S. Mittal
Keyword(s):  
Energy Efficient ◽  
Preference Score ◽  
Drying Method ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Microwave Vacuum Drying ◽  
Hot Air ◽  
Drying Techniques ◽  
Microwave Techniques

AbstractThe aim of this study is to find a better drying method to replace conventional hot air drying (HAD) in terms of faster, energy efficient and better product quality. Two alternative drying techniques, microwave combined with hot air drying (MHD) and microwave vacuum drying (MVD), are compared in this study to dry peeled and destoned longan fruit. Both MHD and MVD reduced the drying time up to 48 % and energy consumption as compared to HAD. These techniques provided lower product redness, yellowness and shrinkage but higher lightness and porous structure as compared to HAD. MVD reduced hardness and toughness of the dried product. MHD provided the highest preference score in terms of colour and shape and was as acceptable as the commercial product dried by HAD. MHD is the most suitable method for longan drying.

scholarly journals Development of Hot-Air Dried Cut Persimmon

2011 ◽  
Vol 7 (5) ◽  
Author(s):  
Marta Igual ◽  
María Luisa Castelló ◽  
Eva Roda ◽  
María Dolores Ortolá
Keyword(s):  
Mechanical Properties ◽  
Kinetic Study ◽  
Osmotic Dehydration ◽  
Mass Variation ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Hot Air ◽  
Sensory Analyses ◽  
Optical And Mechanical Properties

In this work the authors have studied the effect of hot-air drying with or without a previous osmotic dehydration pretreatment to produce dried cut persimmon with a different geometry (slices and sectors). A kinetic study has been carried out analysing mass variation, colour and texture changes in samples. Two sensory analyses were also performed considering drying time and geometry. Furthermore, the influence of 35 days of storage on optical and mechanical properties was also determined. The results obtained showed that geometry did not affect the parameters analyzed. According to the results of the kinetic study, the selected drying times were 8 and 12 hours. Osmotic pretreatment does not imply improvements in the final product. Judges preferred slices dried for 8 hours without osmotic pretreatment. The time of storage did not influence the optical and mechanical properties.

scholarly journals Physico-chemical aspects of Thai fermented fish viscera, Tai-Pla, curry powder processed by hot air drying and hybrid microwave-infrared drying

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0253834
Author(s):  
Warongporn Choopan ◽  
Worawan Panpipat ◽  
Mudtorlep Nisoa ◽  
Ling-Zhi Cheong ◽  
Manat Chaijan
Keyword(s):  
Specific Energy Consumption ◽  
Infrared Heating ◽  
Hot Air Drying ◽  
Drying Time ◽  
Air Drying ◽  
Fermented Fish ◽  
Infrared Drying ◽  
Hot Air ◽  
Physico Chemical ◽  
Fish Viscera

The objective of this research was to comparatively investigate the effect of hot air drying (HA) and hybrid microwave-infrared drying (MI) on physico-chemical characteristics of Thai fermented fish viscera, Tai-Pla, curry powder (TCP). HA was carried out at 60°C, 70°C, and 80°C and MI was carried out at a microwave power of 740, 780, and 810 W with a constant infrared heating power (500 W) for different drying times to obtain the final moisture content ≤ 12.0% and the water activity (aw) ≤ 0.6. The quality characteristics of TCP were governed by HA temperature and MI output power. TCP dried using HA and MI at all conditions had similar contents of protein, lipid, ash, fiber, and carbohydrate (p>0.05). The fastest drying rate was detected when MI at 810 W for 40 min was applied (p<0.05). In this condition, TCP had the lowest browning index (A294 and A420) and the highest lightness (L* value) (p<0.05). TCP dried with MI at all powers had higher phenolic content and lower TBARS compared to HA (p<0.05). However, no significant differences in DPPH• scavenging activity were observed among TPC made by HA and MI (p>0.05). Similar Fourier transform infrared (FTIR) spectra with different peak intensities were observed in all samples, indicating the same functional groups with different contents were found. The bulk density of all TCP ranged from 0.51 g/mL to 0.61 g/mL and the wettability ranged from 24.02% to 26.70%. MI at 810 W for 40 min effectively reduced the drying time (5-fold faster) and lowered the specific energy consumption (18-fold lower) compared to the HA at 60°C for 210 min. Therefore, MI is a promising drying technique to reduce the drying time and improve the overall quality of TCP.

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