When dairy farmers at the Straus Family Creamery set out to concoct an organic, low-fat, certified-kosher chocolate milk, they found the process more complicated than expected.

Creating the perfect chocolate milk, it turns out, is something of an art, requiring much more than dropping a few spoonfuls of sugar and cocoa into a bottle of milk and giving it a good shake.

The chocolate milk, which arose in response to customer requests, will join other certified-kosher products — milk, butter and yogurt — made at the Jewish-owned creamery. Only the cheese made there is not certified kosher.

When the development process first began, the creamery wanted to make a delicious, full-fat variety, according to Vivien Straus, marketing director of the Tamales Bay creamery.

But with no homogenization, it was decided that brown chocolate milk with a white layer of cream floating on top wouldn't look as appetizing as it might taste.

Then came an attempt to blend cocoa, sugar and non-fat milk. But without an emulsifier, the dairy farmers watched the syrup fall to the bottom of the bottles. No amount of coaxing could get the syrup to remix with the milk.

Emulsifiers such as guar gum, soy lecithin and carageenan would have rectified the problem. But the Strauses eschewed those additives, worried they would mar the taste of the milk and sabotage the simple product they had envisioned.

"We wanted something refreshing and clean," said Straus, daughter of creamery founders Bill and Ellen Straus. "We have always been a company that has tried very hard not to use additives."

Finally, the chocolate milk team hit upon a "native cornstarch" approved for use in organic products. Unlike modified cornstarch, native cornstarch is processed without the use of chemicals.

Now the chocolate syrup will fall to the bottom, creating a layer of milk and syrup, with occasional flecks of sweet cream floating on top. But the chocolate milk will easily shake up into a smooth liquid again.

Depending on their level of observance, some Jews like their milk products certified kosher, or made at a plant inspected by a rabbi who ascertains the plant is cleaned according to kosher standards and that milk and meat products do not mix.

For example, kosher yogurt cannot contain beef gelatin or animal protein enzymes.

Some Jews go a step further, preferring their milk be Chalav Yisrael, or processed from start to finish in the presence of a Jew who observes kosher laws. The Straus Family Creamery does not make such products.

The creamery, founded in 1941 by a German-born Jew who immigrated to America from Israel, is the first certified organic dairy farm in the Western United States. That means cows are not fed any hormones, and no herbicides or pesticides are used on the food they eat.

The new chocolate milk, packaged in quart-sized glass bottles and sold for about $2.39, can be found at Andronico's, Whole Foods and other stores.