Coffee is extracted from coffee beans through the process of leaching using____________________?
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Answer: B. Hot water
Explanation
Hot water acts as an efficient polar solvent capable of dissolving soluble aromatic compounds from coffee beans. Elevated temperatures increase mass transfer rates and solubility coefficients during the leaching operation. Thermal energy softens cellular structures inside the coffee beans to facilitate rapid extraction of solubles. Leaching or solid-liquid extraction involves selectively dissolving soluble constituents from an inert solid matrix. Solvent selection depends upon solute solubility, boiling point, safety, and economic cost factors. Diffusion of soluble compounds out of porous solid structures limits the overall extraction rate.
Food processing industries utilize hot water leaching for manufacturing instant coffee powders on a massive scale. Optimizing extraction temperature and contact time ensures maximum recovery of desired flavor compounds. Similar leaching principles apply across various chemical engineering industries for extracting valuable natural products. Option A is incorrect because cold water provides extremely slow extraction rates and poor solubility yields. Option C is wrong since caustic solutions would severely degrade the flavor and chemical composition of coffee. Option D is incorrect because naphtha is a non-polar petroleum solvent unsuited for extracting water-soluble coffee compounds.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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