The Callahan family do not buy sheep; all their sheep are born and raised on the farm. They eat the farm grass, which is supplemented with some alfalfa.

"Our sheep have access to the pasture year round" says Liam. Even when it is dry and there are only seed heads available, the sheep nibble on this."

In the last few years the Callahan's have started producing cheese from raw instead of pasteurized milk. The reason, Liam says, is that raw milk cheeses retain more of their distinctive flavor derived from the terroir.(Today, the majority of the world's cheeses are made from pasteurized or heat treated milk. Pasteurization means the milk is heated to a specific temperature and maintained to partly sterilize it and kill potentially bad bacteria, such as Listeria.

Some cheese makers believe the process destroys important enzymes that aid in the flavor and aging of the cheese.) With heat-treatment, the temperature of the milk is raised to a slightly lower temperature to kill bad bacteria. This method is 'said' to preserve more of the important enzymes, but opinions vary regarding this. Still other cheese makers insist on using unpasteurized milk. Raw milk cheeses or unpasteurized cheeses, are believed by many to retain more of their distinctive character.

The Callahans believed that using raw milk (unpasteurized) was a positive way to increase Bellwether's identity in the market place.

"The cheeses are also aged on 'wooden slats"' says Liam. "This also contributes to the taste of the cheese. The wood helps to inoculate the rind, allowing for a smear and mold growth on the cheese, which is eventually washed off. All of this factors into how the cheese ripens.
Bellwether Farms identity can also be attributed to the laws and regulations in the dairy industry with regards to bacteria. In California, the threshold for bacteria is much lower than that of Europe. This bacteria, in part, comes from the manure on the sheep's underbelly (the animal sleeps on the ground) or is simply sediment (dirt) which is imparted to the milk during milking. In California the inspection system is restrictive. The animals must be 'prepped' before milking to reduce the level of bacteria in the milk. This means the udder must be washed prior to milking. After milking, most farmer do a treatment that prevents a possible migration of bacteria, such as Mastitis (an infection of the udder), back into the udder. This in turn produces a 'cleaner' milk. And while this bacteria contributes toward the sharpness of European cheese, it gives California cheeses a sweeter flavor.

By embracing the concept of terroir, the Callahans started to feel confident in their cheese making abilities. Liam created his first cheese called Fresco. The public responded positively. They entered the cheese in the American Cheese Society Competition in I996 and won in two categories, the 'Best Farmstead Sheep Cheese' and the 'Best Aged Sheep Cheese'. This success encouraged them to continue developing their own style.

"Over the years I have played with the ripening conditions. Over time Fresco evolved into what is now our San Andreas," says Liam. "While this sounds like a European name for a cheese, it is actually named after the Earthquake fault that runs under our property. The recipe is clearly Italian, but the San Andreas is distinctively a Bellwether cheese.

The Callahans started making cheese in small batches in 1990. The family had been producing lamb since I986, which they sold to Bay Area restaurants. In I990 they rented space at a local farm on weekends and produced a fresh Fromage Blanc, which they sold at farmer's markets. In 1992, after travelling to Tuscany and spending a month touring various farms to learn about the Italian process, the family returned home and decided to produce aged cheeses. In thc fall of 1992 they obtained a license and began production of sheep's milk cheeses on the premises where the farm now sits, on Carmody Road near the town of Valley Ford.

"This was certainly not an economic decision' says Liam. "Something that you age for four months verses something that you, can make and sell in a week. It wasn't the smartest method. But we liked the cheeses, and we wanted to do something that was more exciting, something where we were more involved in making the cheese."