studies on hot air and microwave vacuum drying of wild

Drying of edamames by hot air and vacuum microwave

Edamame was subjected to 70 C hot air drying for 20 min and then microwave dried at power intensity 9 33 W/g for 15 min under -95 kPa (gauge pressure) The optimized combination drying process exhibited significantly shortened drying time as compared with conventional hot air drying and greatly decreased mass loads on the vacuum microwave

The Drying of Foods and Its Effect on the Physical

Figure 1 Solar Drying of pears B Hot Air Convective Drying The convective drying of porous media including foods has a pivotal role in several industrial applications Owing to its high availability and moisture saturation capacity the air is undoubtedly the most used drying fluid [10] The methods in which hot air is used for drying foods

Vol 38 (N 52) Year 2017 Page 35 A review of techniques

(80%) and for reutilization microwave-vacuum drying (1 33kPa for 40min) was suggested to be performed under temperature control by varying setting parameters of the microwave oven As a result an undamaged dried product (7 8% wet basis) of high organoleptic quality was

Effects of Freeze Vacuum Drying Combined with 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

Studies on combined hot

Orthogonal test was carried out to investigate the effects of hot air temperature conversed moisture content microwave intensity and pulse ratio on the L value of the dried litchi pulp specific energy consumption and sensory score respectively The results showed that the optimum conditions for drying of litchi pulp by hot air and vacuum microwave combination were found to be hot air

Influence of Various Drying Conditions on Phytochemical

study various drying conditions including hot-air (50 C and 100 C) vacuum (50 C and 100 C) microwave (600 W and 1200 W) and freeze dying ( 45 C) were applied and the phytochemical yield and antioxidant activity of carrot peel were then assessed

The impacts of vacuum microwave drying on osmosis

HAD = hot air drying VMD = vacuum microwave drying O‐MD = osmosis microwave osmosis vacuum microwave drying = O‐VMD The crude fat content following HAD (3 74 g/100 g) was significantly lower than those following other treatments (4 90–5 45 g/100 g) similar to the findings in another report (Wu Mao 2008 )


of the microwave assisted vacuum process (MAVP) with two other drying processes one using hot air convection and the other combining microwaves with hot air convection The results of such a study showed that the drying kinetics were not affected by the vacuum levels whereas the absorbed microwave power was higher for smaller vacuum levels

Effects of Combined Coating and Microwave Assisted Hot

The effect of coating hot-air and microwave drying on the texture microstructure and rehydration characteristics of Golden Deliciousapple slices (22mm diameter 4mm thickness) was investigated Blanching was carried out in hot water (80C 1 min) to prevent undesirable enzymatic reactions

Characterisation of the Convective Hot

The preservation of active constituents in Cassia alata through the removal of moisture is crucial in producing a final product with high antioxidant activity This study aims to determine the influences of various drying methods and drying conditions on the antioxidant activity volatiles and phytosterols content of C alata The drying methods used were convective drying (CD)

Critical review of radio

In RF drying the temperature increased rapidly when compared with vacuum or hot air drying because the moisture content plays an important role in the rise of treated food temperature by RF-H (9 8% dry basis) The RF-drying rate was faster than that of vacuum or hot air drying

Optimization of Microwave Vacuum Drying and Pretreatment

2 4 Mathematical Models The data on the drying of P cuspidatum slices in microwave vacuum dryer were used to study the drying kinetics and to analyze the fit of mathematical models on thin-layer drying including Newton Page logarithmic Wang and Singh Henderson and Pabis two-term and Midilli et al models (Table 2) In Table 2 the MR in (i)–(vii) is the moisture ratio

Vacuum Drying

Vacuum drying is a batch operation performed in an air-tight vessel Using vacuum pumps the pressure and humidity within the chamber are reduced By lowering the atmospheric pressure within the chamber the materials inside dry more quickly through contact with the indirectly heated walls In this sense vacuum drying is essentially contact

Flavor Volatiles and Physical Properties of Vacuum

Basil (Ocimum basilicum L ) was dried using conventional hot air or the recently developed vacuum-microwave dryers The effect of the drying method on the relative abundance of major flavor volatiles rehydration rate color and structural integrity of the plant was evaluated Dynamic headspace analysis of volatiles present in fresh or dried basil revealed that linalool and

Drying Technology: Trends and Applications in Postharvest

Apr 23 2010Thermal drying technologies have attracted significant RD efforts owing to the rising demand for improved product quality and reduced operating cost as well as diminished environmental impact Drying materials may appear in the form of wet solid liquid suspension or paste which require drying to extend the period of storage ease of transportation and for

Characterisation of the Convective Hot

Characterisation of the Convective Hot-Air Drying and Vacuum Microwave Drying of Cassia alata: Antioxidant Activity Essential Oil Volatile Composition and Quality Studies by Lisa Yen Wen Chua 1 Bee Lin Chua 1 * Adam Figiel 2 Chien Hwa Chong 3 Aneta Wojdyło 4 Antoni Szumny 5 and Krzysztof Lech 2

Dehydration of Garlic Slices by Combined Microwave

Combination of microwave-vacuum drying and air drying was investigated as a potential mean for drying garlic slices The sample was dried by microwave-vacuum until the moisture content reached 10% (wet basis) and then by conventional hot-air drying at the temperature of 45C to final moisture content less than 5% (wet basis)

Dehydration of Garlic Slices by Combined Microwave

Combination of microwave-vacuum drying and air drying was investigated as a potential mean for drying garlic slices The sample was dried by microwave-vacuum until the moisture content reached 10% (wet basis) and then by conventional hot-air drying at the temperature of 45C to final moisture content less than 5% (wet basis)

Effect of air

drying techniques such as hot-air drying (Dirim and Caliskan 2012) freeze drying (Que et al 2008) spray drying (Shavakhi et al 2012) vacuum drying (Arvalo-Pinedo and Murr 2006) and microwave vacuum drying (Rakcejeva et al 2011) have been studied Specifically the hot-air drying method

Microwave Vacuum and Air Drying Characteristics of

Collard leaves (Brassica oleracea L var acephala) with an initial moisture content of 6 65 on percentage dry basis (%db) were dried by three different drying methods: microwave air and vacuum Samples of fresh leaves 25 g each were dried until their moisture was down to 0 1 on a dry basis The following drying levels were used in each of the drying processes: 350 500

Drying of edamames by hot air and vacuum microwave

Dec 01 20062 3 Drying procedures Preparation of materials: Deep-frozen edamames were unfrozen at room temperature immersed in 3% salt solution for 1 h and then drained Hot air drying: The pretreated materials were spread uniformly as a single layer on the bed (mesh) of tray dryer Hot air was flowed perpendicularly through the bed at 1 5 m/s velocity and 20%


Jun 01 2017Three vacuum levels (200 400 600 mm Hg) and microwave power levels (100 200 300 W) were also used to dry green bell pepper samples in a vacuum assisted microwave (VAM) (2 45 GHz 0 8 kW) dryer VAM drying methods offered a maximum reduction by four to five times in drying time as compared to that in HAD

Application of Microwave in Food Drying

Feb 06 2015with hot air blast and the products were compared to those of traditional drying process i e freeze drying hot air blast and vacuum drying Test panel assessments of onion showed that freeze-dried product became softer than microwave dried one There were few differences in colours between different drying methods for carrots

Evaluation of seven different drying treatments in respect

Sep 17 2015Furthermore in comparison to hot air drying microwave drying techniques can greatly reduce the drying time of biological materials without quality degradation Recently microwave drying has gained popularity as an alternative drying method for a variety of food products such as fruits vegetables snack foods and dairy products (Hamrouni