Syrups: Composition and Properties

Syrups: Composition, Preservation, and Properties

• Syrups are sweet, viscous aqueous liquids, categorized medically as either nonmedicated (flavoring) or medicated.
• Nonmedicated syrups are used as palatable carriers for medicinal ingredients (e.g., cherry, orange, simple).
• Medicated syrups contain ingredients for their therapeutic effect (e.g., antitussives, antihistamines).
• Syrups are classified pharmaceutically by their base: sugar-based or sugar-free.
• Sugar-based syrups use concentrated sugar solutions (e.g., sucrose, dextrose), and sucrose is preferred due to its purity, sweetness, lack of color, ease of handling, and inertness.
• Sugar-free syrups use artificial sweeteners (e.g., sorbitol).

Sucrose Degradation

• Sucrose, a disaccharide, is susceptible to two degradation pathways: fermentation and hydrolysis.
• Sucrose in dilute solution serves as a nutrient for microorganisms (molds, yeasts).
• Signs of microbial growth include turbidity (color change), fermentation (odor change), and taste alteration.
• Sucrose concentration is important; saturated solutions, properly stored, inhibit mold growth.
• This occurs because a saturated solution contains no free water, acting as an anhydrous medium, inhibiting microbial growth and leading to shrinkage and lysis of microorganisms.

Syrup Preservation

• Preservatives suitable for use in syrups include benzoates, parabens, sorbic acid, and mixtures of methyl and butyl parabens.
• Small amounts of alcohol (not exceeding 10%) can be added as a solubilizing agent for alcohol-soluble ingredients and to prevent surface mold growth; alcohol evaporates, leaving concentrated alcohol behind.

Hydrolysis of Sucrose

• Sucrose hydrolysis, catalyzed by acid, breaks down sucrose into monosaccharides: dextrose and fructose.
• This reaction, called inversion, produces invert sugars (dextrose and fructose).
• Invert sugars are more easily fermented and sweeter than sucrose.
• Degradation of fructose (a product of hydrolysis) leads to the browning (caramelization) of some colorless syrups, particularly when acids are present.

Syrup Storage

• Syrups are typically stored at room temperature in tightly stoppered, well-filled bottles.
• Both saturation and refrigeration inhibit mold growth and inversion.
• Storage below 4°C can cause crystallization (difficult to re-dissolve).

Explore the fascinating world of syrups, including their composition, preservation methods, and medicinal properties. This quiz covers both nonmedicated and medicated syrups, their classifications, and the degradation of sucrose in various conditions. Test your knowledge about sugar-based and sugar-free syrups in this informative quiz.