Design and development of centrifugal dewatering machine for vegetable
Research Type
Departmental Research
Experiment Background
An important factor for the stability of fresh-cut product is moisture control. After washing, the excess water should be removed from the fresh-cut product before packaging, to prevent rapid microbial development and enzymatic processes that lead to product quality deterioration. Various methods exist to remove washing water, including centrifugation, passing the produce over vibrating screens with air blasts, or blotting. Water remaining on the product is a critical issue. The most widely used method to dewater product in the fresh-cut industry is via centrifugation (spinning to force water to the outside of a perforated basket).There is a growing importance in the food industry about the use of low speed basket centrifuge to dewater or dry the surface water of washed fresh cut vegetables, especially salads greens, for later use in modified atmosphere packaging. The key factors while considering this system are duration and speed of centrifugation. Minimal centrifugation can leave residual water on the produce surface, thus favoring microbial growth, while excessive centrifugation can result incellular damage and cause cellular leakage, greatly reducing quality. Fresh-cut products are often left with toomuch moisture, which causes rapid deterioration.
The centrifuge can be loaded manually with the aim to gently and effectively remove the water from the surface of the product after washing. Even for this machine, attention must be paid in the construction phase of simplicity, heavy duty and hygiene. The centrifugal system should offer the possibility to select the correct rotational speed for each product. In the model’s operation, the cycle of centrifugation usually start with modest load, especially in the case of delicate products such as certain types of salads. These then undergoes increasing spinning speed (i.e., accentuated progressively) followed by decreasing spinning speed before the discharged of dewatered product. The basket must have the inner surface completely smooth without central axis or contact part that could directly damage the product. For hygiene reasons, contact part should be food grade plastic and SS304 along with branded drive with motor that could deliver at the same time an almost silent operation sequence cycle. The machine should lighter construction, batch type and have reusable rotating perforated baskets, to facilitate rapid loading and unloading of the centrifuge. The reusable perforated baskets should usually of light construction, often plastic to allow easy manual handling and economic replacement. Plastic have low tolerance for acceleration and deceleration forces but are well suited for undemanding application. In a view to develop a portable dewatering machine for vegetable, this study is taken with following objectives:
Experiment Group
Agricultural Engineering
Unit Type
(02)EDUCATION UNIT
Unit
(13)ASPEE COLLEGE OF HORTICULTURE (NAVSARI)
Department
(218)Post Harvest Technology,ACHF, Navsari
BudgetHead
(329/12935/00)329/01/REG/00285
Objective
1.Design of a centrifugal dewatering machine suited for fresh and cut- vegetables.
2. Development and fabrication of the machine.
3. Evaluation of effect of speed and operation duration on dewatering of vegetable.
Season
Annual
Location Unit Type
(02)EDUCATION UNIT
Location Unit
(13)ASPEE COLLEGE OF HORTICULTURE (NAVSARI)
Location Department
(218)Post Harvest Technology,ACHF, Navsari
Plot No
PHT Lab
PI Name
(NAU-EMP-2013-000924)FAKIR MOHAN SAHU
PI Email
fmsphtc@nau.in
PI Mobile
9879123286
Year of Approval
2017
Commencement Year
2018
Completion Year
2025
Design of Experiment (Other)
Design Variables
Dependent Variables
Independent Variables
Size and Shape of inner basket
Bulk density of crop
Power requirement of machine
Moisture content of crop before and after washing
Dimension and shape of outer bowl
Weight of crop before and after washing
Structure of machine
Material of basket
Opening diameter (perforation) of basket
Weight and dimensions of kinematics component of machine
Treatment details for performance evaluation and standardization: