Eating cholent has long been seen thought of as the traditional, if not the most dietetic, Shabbat lunch.

However, new research, centring on the Ashkenazi slow-cooked mix of beef, potato, pulses and other ingredients, now points to the exciting possibility that cholent, if eaten in sufficient quantities, could be the key to a longer life.

Israeli scientists have long wrestled with the reasons why a disproportionate number of Ashkenazi Jews live past 100. Previous research has centred on their DNA - but now researchers believe the answer could be their lunch.

Mordecai Bedichah of the University of Ra'anana revealed this week that when beef and pulses are cooked together for an extended period of time, a little known enzyme, known as esterzine, is released.

When released into the body, this enzyme is known to slow down chemical reactions within cells and could be the key to elongating life. While scientists have long known about its theoretical benefits, this is the first time that it has been found to be delivered to the body in useable form. Mr Bedichah said: "Many people have experienced that feeling of tiredness after a large portion of cholent. Previously we have always put it down to the stodginess and high-fat content of the food. However, now we believe this sensation has more to do with the body's ageing process slowing down."

He added that the crucial component was the length of cooking - it has to be more than 12 hours. He also pointed out that the benefits do not seem to apply to the Sephardi version of the dish, hamin. This might have to do with the fact that hamin uses different ingredients - chicken instead of beef, and rice instead of barley and beans.

Mr Bedichah predicted that, given a diet rich in cholent, people might be expected to live to an average of 120 years. But there could be a problem. He said: "For the full effect you would have to eat cholent in large quantities – perhaps six or seven times a week. However, this could well cause an epidemic of obesity. We could end up with a world full of very old but very fat people. This is a snag we have yet to overcome."