Question

The tests employed when egg yolk is used as an emulsifying agent in ice cream :
A. Total count, coliforms, fungi and Salmonellae
B. Psychrophiles and yeasts
C. Lactic acid bacteria, yeasts, hyperthermophiles
D. Putrefactive anaerobes and \(\beta\)-haemolytic streptococci
E. Psychrotrophs, yeasts, coliforms and aerobic spore formers
Choose the correct answer from the options given below

• A. B and E only
• B. C and E only
• C. A and D only
• D. A and C only

Hint:

Egg Yolk Testing in Ice Cream: High risk of Salmonella enteritidis, Coliforms, and Putrefactive anaerobes $\rightarrow$ Battery A (Total count, coliforms, fungi, Salmonella) + Battery D (Putrefactive anaerobes, $\beta$-haemolytic streptococci).

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Seafood and dairy ingredient safety: egg yolk products carry high risk of Salmonella enteritidis and streptococcal cross-contamination, requiring stringent pathogenic profiling.

Step 2: Detailed Explanation:
In ice cream microbiology and egg ingredient safety testing:
- Fresh, frozen, or spray-dried egg yolk used as a natural emulsifier (lecithin source) is prone to contamination from poultry intestinal tracts and eggshells.
- Standard microbiological quality assurance requires testing for:
1. Standard Hygienic & Enteric Profile (A): Total aerobic plate count, Coliforms, Fungi (molds/yeasts), and Salmonella spp. (specifically Salmonella enterica serovar Enteritidis).
2. Sporeforming & Pyogenic Pathogens (D): Putrefactive anaerobes (Clostridium) and $\beta$-haemolytic streptococci (Streptococcus pyogenes).
- Thus, testing protocols employ battery A and D.

Step 3: Final Answer:
Hence, the tests employed are A and D only, matching option (C).