Regulatory thresholds for sodium content claims:

• Under FSSAI (Advertising and Claims) Regulations and Codex Alimentarius guidelines, a food can be claimed as 'Sodium Free' or 'Salt Free' only when it contains not more than $0.005\text{ g}$ ($5\text{ mg}$) of sodium per $100\text{ g}$ (for solids) or $100\text{ ml}$ (for liquids).
• $0.020\text{ g}$ ($20\text{ mg}$) exceeds the zero/free claim threshold.
• $0.030\text{ g}$ is not a standard regulatory claim threshold.
• 'Very Low Sodium' allows up to $0.040\text{ g}$ ($40\text{ mg}$), and 'Low Sodium' allows up to $0.120\text{ g}$ ($120\text{ mg}$) per $100\text{ g}$.

Microbiological safety standards for drinking water under IS 10500:

• $15\text{ ml}$ is not a standard analytical testing volume.
• $50\text{ ml}$ is not the regulatory membrane filtration aliquot.
• Under Bureau of Indian Standards specification IS 10500 (Drinking Water Specification), both total coliforms and thermotolerant coliform bacteria (or E. coli) shall be absent and non-detectable in any $100\text{ ml}$ sample of treated drinking water.
• $250\text{ ml}$ is used for mineral water packaged tests for Vibrio/Salmonella, but $100\text{ ml}$ is the fundamental coliform test standard.

Mechanism of antimicrobial chemical sanitizers:

• Cationic detergents (such as quaternary ammonium compounds / Quats) possess positively charged hydrophilic heads and hydrophobic hydrocarbon tails that integrate into negatively charged bacterial cell membranes, solubilizing lipid bilayers and causing intracellular leakage and lysis.
• Heavy metals (silver, copper, mercury) act by binding sulfhydryl (-SH) groups to precipitate and denature proteins.
• Halogens (chlorine, iodine) act by oxidizing essential cellular functional groups and enzymatic proteins.
• Aldehydes (formaldehyde, glutaraldehyde) act by cross-linking amino, carboxyl, and sulfhydryl groups.

Classification of market structures by buyers and sellers:

• Monopsony describes a market dominated by a single buyer facing many sellers.
• Oligopsony describes a market form in which the number of buyers is small (few buyers), while the number of sellers is large, typical in agricultural commodities where numerous farmers sell produce to a few large processing corporations.
• Monopolistic competition involves many sellers offering differentiated products to many buyers.
• Oligopoly describes a market dominated by a few sellers facing many buyers.