Pre-decisional draft, do not distribute
Romaine Lettuce
85
Lactuca sativa longifolia
is a columnar heading-type lettuce with firm, spoon-shaped leaves
86
possessing a prominent mid-rib typical surrounding a compact set of elongated central leaves or
87
‘heart’. Typical maturation takes 65 to 80 days in main season and up to 125-130 days during winter
88
production.
89
90
Salmonella
91
Straight rods, 0.7 – 1.5 x 2-5 μm. Gram negative. Usually motile by peritrichous flagella. Facultative
92
anaerobic. Chemoorganotrophic, having both a respiratory and fermentative metabolism. D-
93
glucose and other carbohydrates are catabolized with the production of acid and usually gas.
94
Oxidase negative, catalase positive, indole and Voges-Proskauer negative, methyl red and Simmons
95
citrate positive. Lysine and ornithine decarboxylase positive, there is a variable arginine dihydrolase
96
reaction. H
2
S is produced, urea is not hydrolyzed, growth on KCN and utilization of malonate are
97
variable. Reduce nitrates. Carbohydrates usually fermented include L-arabinose, maltose, D-
98
mannitol, D-mannose, L-rhamnose, D-sorbitol, trehalose, and D-xylose. Occur in humans, warm and
99
cold blooded animals, food, and the environment. Pathogenic for humans and many animal species.
100
Causative agent of typhoid fever, enteric fevers, gastroenteritis, and septicemia
101
102
Test Portion
103
The test portion is the sample size used in most validation studies and is typically 25 grams. A
104
different test portion can be used in validation studies when appropriate. When combining several
105
test portion units into a composite sample, equivalency must be demonstrated in a validation study
106
relative to the test portion of the reference method. For this validation scheme, refer to Appendix J:
107
AOAC INTERNATIONAL Methods Committee Guidelines for Validation of Microbiological Methods for
108
Food and Environmental Surfaces
, or other acceptable international microbiology validation
109
guidelines.
110
111
UCL
112
Upper confidence limit.
113
114
4.
System suitability tests and/or analytical quality control:
115
Positive and negative controls shall be embedded in assays as appropriate. Inhibition controls
116
should be used for method verification for each new matrix.
117
118
Manufacturer must provide written justification if controls are not appropriate to an assay.
119
120
5.
Reference Material(s):
121
None
122
123
6.
Validation Guidance:
124
125
6.1 Appendix J:
AOAC INTERNATIONAL Methods Committee Guidelines for Validation of
126
Microbiological Methods for Food and Environmental Surfaces
(2012); or ISO 16140:2003.
127
128
6.2 Use pre-harvest materials for method evaluation. Do not use processed materials.
129
130
9
Bergey's Manual of Determinative Bacteriology Ninth edition edited by John G. Holt.
3
Draft
Salmonella
SMPR v12
