Standard incubation protocol for the Eijkman thermotolerant coliform test:
(A) The Eijkman test is the definitive confirmatory procedure designed to differentiate fecal coliforms (specifically thermotolerant Escherichia coli) of direct mammalian enteric origin from non-fecal environmental coliforms (like Enterobacter and Klebsiella). Inoculum from presumptive coliform tubes showing gas is transferred into tubes containing EC broth or MacConkey broth and placed into a precision circulating water bath maintained strictly at $44.5 \pm 0.2^\circ\text{C}$ for $24 \pm 2\text{ hours}$. Production of gas in the Durham vial confirms the presence of thermotolerant fecal coliforms.
(B), (C), and (D) deviate from the standard microbiological protocol.

FSSAI Process Hygiene Criteria for pasteurized milk:
Under the Food Safety and Standards (Food Products Standards and Food Additives) Regulations, 2011 (revised Appendix B, Table 2A - Microbiological Process Hygiene Criteria for Milk and Milk Products):
For Pasteurised milk / flavoured milk:

• Test parameter: Coliform count
• Number of sample units ($n$): $5$
• Maximum allowable number of sample units yielding marginal results between $m$ and $M$ ($c$): $0$
• Microbiological limit ($m$): $\lt 1\text{ cfu/ml}$ (or Absent in 1 ml)
  Because coliforms are sensitive to pasteurization and indicate post-pasteurization line contamination, all 5 sampled units must be compliant ($c = 0$), meaning zero samples are permitted to exceed the threshold.

Distinctive motility patterns in diagnostic bacteriology:

• Listeria monocytogenes exhibits characteristic end-over-end 'tumbling motility' when cultured at room temperature (20 to 25 deg C) in wet mount preparations, driven by temperature-dependent expression of peritrichous flagella (it becomes non-motile at 37 deg C).
• Mycobacterium tuberculosis is strictly non-motile.
• Escherichia coli typically displays darting/swimming peritrichous motility.
• Campylobacter jejuni displays characteristic rapid 'corkscrew' or darting motility via polar flagella.