Step 1: Concept Overview:
The question requires distinguishing between stabilizers and emulsifiers within a list of ice cream food additives.
Step 2: Detailed Explanation:
Stabilizers are large molecules (polysaccharides or proteins) that bind water, increasing viscosity and preventing large ice crystal formation. Examples include gums (guar, locust bean), carboxymethyl cellulose (CMC), and alginates.
Emulsifiers are smaller molecules possessing both hydrophilic (water-loving) and lipophilic (fat-loving) properties, facilitating the mixing of fat and water. Examples include mono- and di-glycerides, and polysorbates.
Classifying the options:
(A) Mono - glycerides: An emulsifier.
(B) Sodium alginate: A polysaccharide salt from seaweed; a stabilizer.
(C) Di - glycerides: An emulsifier, often paired with mono-glycerides.
(D) Glycol esters: For example, Propylene Glycol Monostearate (PGMS), an emulsifier.
Step 3: Conclusion:
From the provided options, Sodium alginate is the only stabilizer. The remaining options are emulsifiers.