Food samples. Fresh and frozen chicken and
minced meat were obtained from local retail outlets.
The unpasteurized liquid egg samples were supplied
by the Egg Marketing Board of New South Wales,
Lidcombe. The desiccated coconut samples, five naturally
contaminated with Salmonella, were obtained
from the Division of Analytical Laboratories, New
South Wales Health Commission, Lidcombe, and various
commerical sources. Samples of the meat, egg or
coconut (50 g) were transferred to 450 ml of peptone
water (9) and homogenized for 2 min in a Waring
blender. The chicken pieces or whole chickens were
washed in plastic bags with 100 or 400 ml of peptone
water, respectively. If the samples had been frozen
before examination, the homogenates or washings
were incubated for 6 h at 37°C to allow resuscitation
of sublethally damaged bacteria. Ten-milliliter samples
of the homogenates or washings were transferred
to 100 ml of selenite cystine broth plus 0.5% dulcitol
and tetrathionate broth plus 0.5% dulcitol and incubated
for 18 h at 41 or 370C, respectively. Dulcitol
(0.5%) was added to the enrichment culture media to
reduce the lag period for ['4C]dulcitol fermentation in
the reaction flasks. Selenite broth base with lactose,
not mannitol, must be used for the selenite cystine
broth medium. Tests showed that Salmonella will
metabolize mannitol in preference to dulcitol, and thus
no adaptation to dulcitol occurred during growth in
the enrichment medium containing mannitol
Food samples. Fresh and frozen chicken andminced meat were obtained from local retail outlets.The unpasteurized liquid egg samples were suppliedby the Egg Marketing Board of New South Wales,Lidcombe. The desiccated coconut samples, five naturallycontaminated with Salmonella, were obtainedfrom the Division of Analytical Laboratories, NewSouth Wales Health Commission, Lidcombe, and variouscommerical sources. Samples of the meat, egg orcoconut (50 g) were transferred to 450 ml of peptonewater (9) and homogenized for 2 min in a Waringblender. The chicken pieces or whole chickens werewashed in plastic bags with 100 or 400 ml of peptonewater, respectively. If the samples had been frozenbefore examination, the homogenates or washingswere incubated for 6 h at 37°C to allow resuscitationof sublethally damaged bacteria. Ten-milliliter samplesof the homogenates or washings were transferredto 100 ml of selenite cystine broth plus 0.5% dulcitoland tetrathionate broth plus 0.5% dulcitol and incubatedfor 18 h at 41 or 370C, respectively. Dulcitol(0.5%) was added to the enrichment culture media toreduce the lag period for ['4C]dulcitol fermentation inthe reaction flasks. Selenite broth base with lactose,not mannitol, must be used for the selenite cystinebroth medium. Tests showed that Salmonella willmetabolize mannitol in preference to dulcitol, and thusno adaptation to dulcitol occurred during growth inthe enrichment medium containing mannitol
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