Multipurpose Drying Device

DEHYTRAYTM Drying Capacity Table

 

Crop Type

Initial Moisture

Wet Weight in DEHYTRAYTM

Final Moisture

Dry Weight in DEHYTRAYTM

 

 (% Wet Basis)

kg

lb

 (% Wet Basis)

kg

lb

Apples

85.6

2.20

4.84

6.0

0.34

0.74

Blueberries

92.1

2.20

4.84

8.0

0.25

0.55

Chili Pepper

82.0

2.64

5.81

10.0

0.53

1.16

Garlic

66.3

1.41

3.10

8.0

0.52

1.13

Ginger

90.0

3.08

6.78

11.0

0.35

0.76

Mint

87.9

0.88

1.94

9.0

0.12

0.26

Mushrooms

85.8

2.20

4.84

8.0

0.34

0.75

Tomatoes

96.0

2.42

5.33

11.0

0.11

0.24

Papaya

88.7

3.48

7.65

5.5

0.53

1.17

Shelled corn

30.0

4.50

9.90

13.0

3.62

7.97

Okra

95.0

1.50

3.30

15.0

0.09

0.19

Note: 1 kg  = 1000 g = 2.2 lb

 

How to use the DEHYTRAYTM drying capacity table

  • The drying capacity for the DEHYTRAYTM used in drying these crops are estimates based on thin-layer drying studies and were extrapolated to the DEHYTRAYTM capacity. Note that crop variety could influence the final capacity and so treat these estimates as ballpark estimates.
  • Crops such as fresh fruit and vegetables should be dried in thin slices or chopped in chunks and spread to dry in thin-layer. The smaller or thinner the slice the faster the rate of drying of that crop.
  • The table should be used as follows: about 2.2 kg (4.84 lb) of fresh apples will obtain 0.34 kg (340 g or 0.74 lb) of dried apples.
  • To determine the number of DEHYTRAYTM’s that is needed to dry a batch of 100 kg (220 lb) of apples, this will be 100 kg/2.2 kg (or 220 lb/4.84 lb) equal to 45.5 ~ 46 DEHYTRAYTM’s (from the Table). The 100 kg batch of fresh apples would yield 15.5 kg (33.6 lb) dried apple slices.
  • While the final moisture content of the crop is indicated in the table, we advise that drying crops/foods to a water activity below 0.60 (aw< 0.60) or Equilibrium Relative Humidity, ERH < 60% should be used as the indicator to determine when crop or food has been dried to a safe moisture that would prevent deterioration by molds. A simple mini hygrometer device comes with every DEHYTRAYTM for use in determining when crop or foods has been sufficiently dried.
  • Drying duration is not indicated because they would vary depending on the weather and geographic location where the DEHYTRAYTM is used. Hot dry weather favor rapid solar drying than cold humid weather.
  • In general, the ambient temperature is doubled within the DEHYTRAYTM by the absorbed heat radiating from the tray walls. For example, if the ambient temperature is 25oC (77oF), the temperature inside the DEHYTRAY would be 50oC (154oF).
  • Because the temperature is double inside the DEHYTRAYTM, the humidity inside the tray decreases, thus creating a better drying environment than in open-air ambient sun drying.
  • The vents in the DEHYTRAYTM should be opened to release humid air and prevent condensation. Opening the vent will also cause the temperature to decrease slightly by about 5oC (41oF).

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