Question

The component of TWEEN 80 which gives improved stability to lactic cultures is

• A. Oleic acid
• B. Propionic acid
• C. Butyric acid
• D. Teichoic acid

Hint:

Starter Growth Factors: TWEEN 80 provides OLEIC ACID (Monooleate) for membrane phospholipid synthesis and acid/cryo-stability in MRS media for Lactobacilli.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Lactic starter culture membrane lipid biophysics: Tween 80 (polyoxyethylene sorbitan monooleate) incorporates exogenous cis-unsaturated oleic acid (18:1) and cyclopropane fatty acids (lactobacillic acid) into bacterial plasma membranes, maximizing membrane fluidity and acid/cryotolerance.
Key Formula or Approach:
\[ \text{Tween 80} = \text{Polyoxyethylene Sorbitan Mono}\mathbf{oleate} \xrightarrow{\text{Supplies}} \mathbf{Oleic \text{ } Acid (18:1)} \longrightarrow \text{Lactobacillic Acid (Membrane Stability)} \]

Step 2: Detailed Explanation:
In starter culture growth media formulation (MRS Broth Rogosa Media):
- Tween 80 (Polysorbate 80) is chemically Polyoxyethylene (20) Sorbitan Mono-Oleate.
- The active functional constituent is Oleic Acid (cis-9-octadecenoic acid, 18:1) (A).
- Fastidious lactic acid bacteria (such as Lactobacillus delbrueckii, Lactobacillus acidophilus, Lacticaseibacillus casei) lack desaturase enzymes to synthesize unsaturated fatty acids de novo.
- Incorporating Tween 80 directly provides oleic acid, which is rapidly taken up and converted into Cyclopropane Fatty Acids (Lactobacillic Acid 19:0-cyc) in the cell membrane phospholipids, imparting superior membrane structural integrity, extreme tolerance against lactic acid accumulation, and enhanced survival during freeze-drying and frozen storage.

Step 3: Final Answer:
Therefore, the component of TWEEN 80 is Oleic acid, matching option (A).