The equipment, developed by scientists of Mechanical Engineering Research and Development Organisation (Merado) in Ludhiana, crushes 42 kg of mustard seeds per hour and leaves lesser residual oil content in mustard seeds cakes.

Moisture content in mustard seeds and the temperature range in which they are crushed are critical parameters for getting pungency in oil, scientist-in-charge of Merado said.

These conditions activate the enzyme myrosinase present in mustard seeds which converts the ``glucosinolates'' in the seeds into allyl iso-thiocyanate -- an essential oil responsible for pungency in mustard oil.

Due to high temperature (80 to 100 degree celsius) in the chambers of conventional oil expellers, the allyl iso-thiocyanate evaporates resulting in no pungency.The new expeller incorporates some additional features to maintain the pungency of traditional mustard oil, he said.

The technology, funded by the technology mission on oil seeds and pulses (TMO&P) of the agriculture ministry, has been transferred to four companies -- two in Ludhiana and one each in Kanpur and Calcutta.

Merado is a unit under the central mehanical engineering research institute (CMERI) in Durgapur.

The residual oil left in the mustard seed cakes is about nine per cent compared to 15 per cent in case of ``ghanis.''

The 12-quintal equipment costing Rs 45,000 has a water-cooled chamber for temperature-controlled crushing and helical gears specially treated for longer life. It also has an automatic cake recycling and conveying system.

The extraction process is hygienic and critical components of the machine have longer life, Merado scientists said.

TMO&P is actively considering to fund 75 per cent of installation costs of 10 such expellers in the country. Rest would be funded by therespective state governments.

The scheme will be implemented by the Council of Scientific and Industrial Research (CSIR) on behalf of TMO&P.

Two such expellers are already operating in the north-east and three more are due to start operation, according to head of Merado's business development group, MP Dhupar .

Merado would evaluate the feasibility of using the machine for extracting oil from other non-conventional seeds.