State officials are supporting a federal investigation into the outbreak.
Twenty-six states have been affected so far.
One Californian has died from the bacteria.
Dr. James Watt from the California Department of Public Health says this particular strain is resistant to many antibiotics.
WATT: Most people who are exposed to salmonella, have a mild gastrointestinal illness, but elderly people, people who are immune compromised can have a severe illness that results in hospitalization or even death.
Watt says the state is helping the Centers for Disease Control to identify cases and find the source of the salmonella.
WATT: Once we know what the source is, we can take appropriate steps to prevent that source from being in the food supply and infecting other people.
Cases have been reported in Sacramento, Los Angeles, San Diego and San Francisco.