“INVESTIGATION OF INTERMITTENT MICROWAVE-

CONVECTIVE FRUIT DRYING FOR OPTIMIZING PRODUCT

QUALITY”BEB801-PROJECT 1

MD HASAN ZUBAIR(N8405221)

SUPERVISOR: DR AZHARUL KARIM

AIM OF THE PROJECT

• Investigate the drying condition of the intermittent microwave convective drying(IMCD) process and optimize the product quality by choosing the most suitable temperature, power level and time ,which will be taken into consideration, so that the maximum efficiency of the drying is achieved ,using Response surface methodology(RSM).

OBJECTIVE OF PROJECT 1

• To investigate power level, pulse ration and hot air temperature.

• To investigate the effect of porosity, colour changes during drying and rehydration ratio.

• To use computer software Design expert 10.0 for the 3D graph to analyse the effect of drying condition on response surface plot results from the experiment data.

EVOLUTION OF FOOD DRYING HISTORY OF FOOD DRYING (HAYASHI, 1989)

BC/AD Civilization Drying technique

12000 BC Middle east- Fruit : Hot sun

10000 BC Mesolithic Age-

southern France

Fish drying

630AD-1630AD Mongolia Sundried-powdered milk

1700 France dehydration

1800 France Hot air 40deg C

MODERN DAY DRYING TECHNIQUE

Convective hot air drying

Microwave Drying

Microwave convective Drying

Intermittent microwave convective Drying

Pneumatic conveyer drying

Belt-Trough drying

Fluidized bed drying

WHY INTERMITTENT MICROWAVE CONVECTIVE DRYING

• Continuous heating makes the food dehydrate quickly, which is a loss of nutrient on the other hand intermittent drying keep the moisture content to a minimum level which controls the quality of the fruit and texture.

• IMCD prevent overheating and redistribute temp and moisture, which is the problem microwave drying alone

MICROWAVE SELECTION AND MODIFICATION

• Panasonic NN-SD691S

• Genius series 1100s

• INVERTER technology

PANASONIC SO POPULAR, COMMERCIAL ADVERTISEMENT BY MASTERCHEFADAM LIEW

HOW IT WORKS (Chandan Kumar, 2013).

HOW IT WORKS

FURTHER MODIFICATION WITH FIBRE OPTICS SENSOR

MICROWAVE FRONT PANEL MODIFIED CONTROL SYSTEM USING ARDUINO SINGLE BOARD MICROCONTROLLER

INVESTIGATION TOPICS• Model for experiment: Box-Bhenken design for optimization

• Methodology: Response surface methodology (RSM)

• Investigation for Optimization: Bulk density

Porosity

Colour changes

Rehydration ratio

Energy consumption

• Computer software: Design expert 10.0 for 3D graph analysis

• Pycnometer to calculate the surface profile of the specimen.

• In project 1, the bulk density, porosity and colour changes will be investigate thoroughly and in Project 2 the investigation will continue on rehydration ratio and energy consumption.

FRUIT SELECTION AND SAMPLE PREPARATION

SELECTING FRUIT: GRANNY SMITH APPLE (AVAILABLE DURING SPRING) AND APRICOT FOR SUMMER• Granny smith apple (GSA) originated from Eastwood, New South

Wales, Australia.

• A cross hybrid of Malus domestica and M.sylvestriz. Named after the cultivator Maria Ann Smith (Martin, 2005).

• GSA can be found in Australia, New Zealand, France and United states. GSA high in antioxidant, low in calories, dietary fibre, rich in all kinds of vitamin such as thiamine, riboflavin, niacin, vitamins B6,folate, vitamin C.

• Lots of minerals like calcium, Iron, Magnesium, Phosphorus, Potassium, Zinc(Blanco-Cano et al., 2016). The availability of GSA is once a year, March-April is the only time to pick from the farm, which makes it ideal to preserve GSA as a dried fruit for the huge demand for the rest of the world (Martin, 2005).

SAMPLE PREPARATION

Washed and peeled

Sample slice thickness 7mm;

Hole diameter 2-3mm

EXPERIMENT AND RESULTS:FRESH SLICE VS 30MINUTES ‘IMCD’ AND COLOUR CHANGES

EXPERIMENT: AFTER 60 MIN AND 120MIN (COLOUR CHANGES )

DRIED SAMPLE OF 60,120,180,200,240,360,480,560 MINUTES

SAMPLE PREPARATION FOR THE PYCNOMETER DENSITY TEST TO CALCULATE POROSITY

EXPERIMENT : ZARCONIUM BALL VS SAMPLE

TRUE DENSITY PYCNOMETER RESULTS OF THE SAMPLE

THEORY BEHIND CALCULATING POROSITY

CALCULATING POROSITY USING BULK AND TRUE DENSITY OF THE SAMPLE

CALCULATING MOISTURE CONTENT

POROSITY VS MOISTURE CONTENT WITH TIME

MOISTURE CONTENT VS TIME

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Moisture content 86.9% 84.1% 80.6% 76.4% 71.2% 64.2% 60.4% 58.0% 55.2% 48.2% 41.6% 35.2% 32% 30% 28%

Time(s) 0 10 20 30 40 50 60 70 80 110 140 170 200 230 260

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Moisture content Vs Time

IMAGE ANALYSIS

SHOWING TEMPERATURE CHANGES DURING DRYING

METHODOLOGY AND OPTIMIZATION

“BULK DENSITY AND TEMPERATURE” AND “ TEMP. VS TIME”

IF TEMP IS 85 C… PREDICTION SHOWING HOW IT EFFECT OTHER FACTOR

OPTIMIZING TIME AND TEMPERATURE

LIMITATION

• Roof access(9pm-3pm)

• Three phase electrical cord not compatible with regular power cord for the system

• System exposed in the sun for long time and microwave malfunction

• Investigate the cause of digital control board broken down twice

• Front panel modification and insulation problem

• If weather is windy or raining : no experiment that day

RECOMMENDATION

• After hour lab access.

• More modification for insulation .

• Fibre optics sensor for measuring temperature inside microwave while cooking.

• Reduce temperature and expand cooking time for more quality product

REFERENCE LIST• Hayashi H. (1989) Drying Technologies of Foods -Their History and Future. Drying Technology 7: 315-

369.

• Chandan Kumar JD, MUH Joardder. (2013) Design and construction of a microwave aiisted convective dryer for food materials. Mechanical Engineering. Garden Point , Brisbane Queensland University Of Technology .

• Martin M. (2005) Smith, Maria Ann (1799–1870)Australian Dictionary of Biography. Sydney: National Centre of Biography , Australian National University.

• Blanco-Cano L, Soria-Verdugo A, Garcia-Gutierrez LM, et al. (2016) Modeling the thin-layer drying process of Granny Smith apples: Application in an indirect solar dryer. Applied Thermal Engineering 108: 1086-1094.

THANK YOU FOR YOUR PATIENCE AND SUPPORT IF YOU HAVE ANY QUESTION??