A specialty chocolate company on Friday expanded its recall of pricey candy bars to include the entire product line over fears of possible contamination with salmonella. Spring & Mulberry – a Raleigh, N.C.-based company that sells date-sweetened chocolates for $10 a bar, or $95 for a variety pack – said an investigation by its manufacturers and the FDA identified “a single lot of date ingredient” as the likely contamination source. Spring & Mulberry expanded its recall to include the entire product line. Spring & Mulberry Salmonella can cause serious and potentially fatal infections in vulnerable populations, including children, elderly individuals or people with weakened immune systems.  In some rare cases, the bacteria can enter the bloodstream and cause serious infections, endocarditis or arthritis, according to food safety officials.…