Agaric acid (agaricic acid, $\alpha$-cetylcitric acid) is a naturally occurring toxic organic tricarboxylic acid found in larch bracket fungi (Fomitopsis officinalis / Polyporus officinalis) historically used to flavor beverages. Under food safety standards (including Codex Alimentarius and FSSAI standards for naturally occurring contaminants), the maximum permitted limit for agaric acid in alcoholic beverages is $100\text{ ppm}$ ($100\text{ mg/kg}$).

Option analysis:

• $10\text{ ppm}$: Limit for some other toxins like thujone in certain foods, not agaric acid in beverages.
• $100\text{ ppm}$: Correct, statutory maximum permissible limit for agaric acid in alcoholic beverages.
• $500\text{ ppm}$: Exceeds maximum safe regulatory limits.
• $1000\text{ ppm}$: High toxic level, unacceptable in foodstuffs.

Silicon oils (specifically polydimethylsiloxane, PDMS, INS 900a) are widely used food-grade antifoaming (defoaming) agents in food processing operations such as frying, fermentation, juice concentration, and jam manufacture. They possess very low surface tension, spreading over foam lamellae to rupture gas bubbles.

Option analysis:

• Silicon oils: Correct, permitted defoamers/antifoaming agents in frying oils and fruit juices.
• Gums: Hydrocolloids used as thickeners, stabilizers, and emulsifiers, not defoamers.
• Cyclamates: Artificial non-nutritive intense sweeteners.
• Hydrocarbons: Petroleum waxes used for coating, not functional defoaming agents.