Assessment of Quality Attributes of Banana Slices Dried by Different Drying Methods

Abstract In the present study, banana slices were dried and compared using electrohydrodynamic (EHD) drying method at 4.5, 6.5, and 8.5 kV/cm; oven at 50, 60, and 70°C; and hot-air drying at 50, 60, and 70°C at a constant air velocity of 1.5 m/s. ANOVA showed that drying method had a significant effect on drying time, rehydration capacity, shrinkage, color features (L*, a*, b*, and ∆E), and consumed energy. The values of consuming energy for EHD at 8.5 kV/cm, oven, and hot-air drying at 70°C were 2.99, 20.9, and 81.7 kJ/g run on full capacity of each dryer, respectively. Oven drying led to a greater color change than did hot-air. No significant difference was observed between the color change feature ∆E for EHD and hot-air dried samples in the orthogonal contrast analysis. The falling rate period for EHD moisture movement showed that diffusion was describing the moisture gradients and the internal moisture transfer was dominant. EHD is not fast; however, its advantages like less energy needed, lower shrinkage, and great rehydration capacity make it a good choice for combining with other convection drying methods.

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

The Journal of Agriculture and Development ◽

10.52997/jad.6.06.2020 ◽

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

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

International Journal of Food Engineering ◽

10.1515/ijfe-2016-0263 ◽

2017 ◽

Vol 13 (7) ◽

Cited By ~ 5

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.

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Quality Characteristics of Semi-Dried Restructured Jerky Processed Using Super-Heated Steam

Foods ◽

10.3390/foods10040762 ◽

2021 ◽

Vol 10 (4) ◽

pp. 762

Author(s):

Se-Myung Kim ◽

Tae-Kyung Kim ◽

Hyun-Wook Kim ◽

Samooel Jung ◽

Hae In Yong ◽

...

Keyword(s):

Moisture Content ◽

Water Activity ◽

Control Sample ◽

Meat Products ◽

Quality Characteristics ◽

Drying Method ◽

Hot Air Drying ◽

Air Drying ◽

Hot Air ◽

Significant Difference

Moisture content and water activity play important roles in extending the shelf life of dried meat products, such as jerky. However, the commonly used hot air drying process is time-consuming, costly, and adversely affects the quality of dried meat products, warranting the development of an advanced and economical drying method. This study investigated the effect of super-heated steam (SHS) drying on the quality characteristics of semi-dried restructured jerky as a measure to prevent the excessive quality deterioration of meat products during drying. The control sample was dried using hot air, and the treatment samples were dried using SHS at different temperatures (200, 250, and 300 °C) and for different durations (90, 105, and 120 min). With increasing SHS temperature and duration, the moisture content, water activity, and residual nitrite content of the jerky were reduced. The shear force values for treatments at 200 and 250 °C were lower than those for the control. With a non-significant difference in lipid oxidation compared with the control, the overall acceptability score was the highest for the treatment at 250 °C for 120 min. In conclusion, SHS (250 °C for 120 min) drying has a potential industrial value to replace the hot air drying method.

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Kurutma Yöntemlerinin Deveci Armudunun Kurutma Kinetiği ve Renk Parametreleri Üzerine Etkisi

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v9i5.897-908.4170 ◽

2021 ◽

Vol 9 (5) ◽

pp. 897-908

Author(s):

Ilknur Alibas ◽

Aslıhan Yılmaz ◽

Seda Günaydın ◽

Begüm Arkain

Keyword(s):

Energy Consumption ◽

Specific Energy Consumption ◽

Initial Moisture Content ◽

Quality Parameters ◽

Drying Method ◽

Hot Air Drying ◽

Drying Time ◽

Air Drying ◽

Hot Air ◽

Thin Layer Drying

Deveci pear (Pyrus communis L. cv. Deveci) slices, whose initial moisture content is 5.24 ± 0.003 kgsu kgKM-1 (%83.95 ± 0.01 w.b), were dried by shade drying and hot-air drying at 60, 80 and 100°C until the final moisture reached 0.13 ± 0.001 kgsu kgKM-1 (%11.40 ± 0.06 w.b), and the drying processes of these methods were completed in 11150, 437, 252, and 148 minutes, respectively. In the study, experimentally obtained time-dependent moisture ratios were modeled using twenty different thin-layer drying equations. Accordingly, the model that gives the closest results to experimental data for 60°C and 100°C was the Modified Henderson & Pabis's equation. On the other hand, Alibas equation and Jena & Das equation were found to be the best models in shade drying and hot-air drying at 80°C, respectively. Despite no energy consumption in the shade drying method, some reasons such as this method being quite long and causing negative effects on the quality parameters of the product revealed that the shade drying method was not suitable for drying of Deveci pear. It was observed that total energy consumption increased with the increase of the drying temperature. Also, it was determined that the increase in temperature negatively affected the quality parameters. It was found to be a suitable method for drying the Deveci pear of the hot-air drying at 60°C due to the operating parameters such as drying time and specific energy consumption, as well as quality parameters such as brightness, redness, yellowness, chroma, hue angle, total color change and browning index were very close to the fresh product.

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Quality evaluation of different pre-treatments and combined convective-freeze drying of sour cherry (Prunus Cerasus L.)

Progress in Agricultural Engineering Sciences ◽

10.1556/progress.10.2014.2 ◽

2014 ◽

Vol 10 (1) ◽

pp. 17-33

Author(s):

T. Antal ◽

L. Sikolya ◽

B. Kerekes

Keyword(s):

Freeze Drying ◽

Sour Cherry ◽

Quality Parameters ◽

Boiling Water ◽

Drying Methods ◽

Sugar Solution ◽

Hot Air Drying ◽

Drying Time ◽

Air Drying ◽

Hot Air

In this study, the influences of various pre-treatments and combined drying (CD) on the drying kinetics and quality parameters of sour cherry were investigated. Prior to freeze drying (FD), sour cherry was pre-treated by blanching in boiling water (100 °C, 3 and 6 min), immersion in sugar solution (20% w/w, 10 and 20 min) and blanching (100 °C) in sugar solution (20% w/w, 3 and 6 min). Freeze-drying of raw samples was taken as a control. Combined drying (CD) can be accomplished in two distinct ways: freeze drying assisted with hot-air drying application (FD-HAD) and hot-air drying followed by freeze drying (HAD-FD). The quality of the dried sour cherry was evaluated in terms of water activity, color, texture and rehydration. Our research results have shown that all of the pre-treatments can effectively reduce the freeze drying time, the best treatment methods are FD-HAD, HAD-FD and blanching in boiling water (6 min). CD involves much less drying time and energy consumption than conventional freeze drying methods. The highest values of hardness and rehydration were found in blanching in sugar solution with water at 100 °C for 6 min. The better color retention was observed for samples pre-treated with blanching in boiling water (6 min).

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Influence of time-based hot air-drying method on total polyphenols, total antioxidants and tannins of Jatropha zeyheri tea leaves

Research on Crops ◽

10.31830/2348-7542.2019.027 ◽

2019 ◽

Vol 20 (1) ◽

Keyword(s):

Drying Method ◽

Tea Leaves ◽

Hot Air Drying ◽

Total Polyphenols ◽

Air Drying ◽

Hot Air

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Supercritical CO2 Extraction of Phytocompounds from Olive Pomace Subjected to Different Drying Methods

Molecules ◽

10.3390/molecules26030598 ◽

2021 ◽

Vol 26 (3) ◽

pp. 598

Author(s):

Graziana Difonzo ◽

Antonella Aresta ◽

Pietro Cotugno ◽

Roberta Ragni ◽

Giacomo Squeo ◽

...

Keyword(s):

Olive Oil ◽

Freeze Drying ◽

Oil Production ◽

Production Costs ◽

Drying Methods ◽

Olive Pomace ◽

Hot Air Drying ◽

Air Drying ◽

Hot Air ◽

Pharmaceutical Industries

Olive pomace is a semisolid by-product of olive oil production and represents a valuable source of functional phytocompounds. The valorization of agro-food chain by-products represents a key factor in reducing production costs, providing benefits related to their reuse. On this ground, we herein investigate extraction methods with supercritical carbon dioxide (SC-CO2) of functional phytocompounds from olive pomace samples subjected to two different drying methods, i.e., freeze drying and hot-air drying. Olive pomace was produced using the two most common industrial olive oil production processes, one based on the two-phase (2P) decanter and one based on the three-phase (3P) decanter. Our results show that freeze drying more efficiently preserves phytocompounds such as α-tocopherol, carotenoids, chlorophylls, and polyphenols, whereas hot-air drying does not compromise the β-sitosterol content and the extraction of squalene is not dependent on the drying method used. Moreover, higher amounts of α-tocopherol and polyphenols were extracted from 2P olive pomace, while β-sitosterol, chlorophylls, and carotenoids were more concentrated in 3P olive pomace. Finally, tocopherol and pigment/polyphenol fractions exerted antioxidant activity in vitro and in accelerated oxidative conditions. These results highlight the potential of olive pomace to be upcycled by extracting from it, with green methods, functional phytocompounds for reuse in food and pharmaceutical industries.

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