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Difficulty: MediumChemistry in Daily Life and Industrial Applications

In culinary and food chemistry, baking powder is prepared by mixing baking soda (NaHCO3\text{NaHCO}_3) with a mild edible organic acid such as tartaric acid. What is the primary purpose of incorporating this edible acid into the formulation?

  1. To neutralize the alkaline sodium carbonate formed upon heating and prevent a bitter tasteAnswer
  2. B
    To act as an oxidizing agent that bleaches flour pigments for a whiter baked product
  3. C
    To drastically lower the dough pH to act as a broad-spectrum antimicrobial preservative
  4. D
    To enzymatically catalyze the breakdown of complex starches into fermentable simple sugars

Answer

The primary purpose is to neutralize the alkaline sodium carbonate formed upon heating and prevent a bitter taste in the finished food product.
When baking soda (NaHCO3 \text{NaHCO}_3 ) is heated during baking, it undergoes thermal decomposition to release carbon dioxide gas along with sodium carbonate (Na2CO3 \text{Na}_2\text{CO}_3 ). Sodium carbonate is an alkaline compound that imparts an unpleasant bitter taste and yellowish hue to baked items. Adding an edible acid, such as tartaric acid or cream of tartar, supplies hydrogen ions that neutralize the basic sodium carbonate to form harmless, neutral sodium salts, thereby eliminating bitterness and facilitating smooth dough rising.

Step-by-Step Solution

1
Analyze the thermal decomposition reaction of pure baking soda (NaHCO3 \text{NaHCO}_3 )
Heating baking soda alone yields sodium carbonate, water, and carbon dioxide: 2NaHCO3→ΔNa2CO3+H2O+CO2↑2\text{NaHCO}_3 \xrightarrow{\Delta} \text{Na}_2\text{CO}_3 + \text{H}_2\text{O} + \text{CO}_2 \uparrow
Understanding the byproduct of unneutralized baking soda reveals the chemical challenge in baking.
2
Determine the chemical properties of the reaction byproduct (Na2CO3 \text{Na}_2\text{CO}_3 )
Sodium carbonate (Na2CO3 \text{Na}_2\text{CO}_3 ) is a basic/alkaline salt that imparts an unpalatable bitter taste and a yellowish tinge to bread and cakes.
Alkaline compounds possess an inherently bitter flavor and affect food texture and aesthetics.
3
Evaluate the neutralizing role of the added edible acid (tartaric acid / C4H6O6 \text{C}_4\text{H}_6\text{O}_6 )
The acid provides H+ \text{H}^+ ions that react with Na2CO3 \text{Na}_2\text{CO}_3 (or directly with NaHCO3 \text{NaHCO}_3 in the presence of moisture), producing sodium tartrate, water, and extra CO2 \text{CO}_2 gas: NaHCO3+H+→Na++H2O+CO2↑\text{NaHCO}_3 + \text{H}^+ \rightarrow \text{Na}^+ + \text{H}_2\text{O} + \text{CO}_2 \uparrow
Neutralization eliminates the alkaline residue, removing bitterness while ensuring maximum leavening action.

Key Concept

Chemical leavening mechanism of baking powder and neutralization of alkaline residues by edible acids
Estimated Time:1m 0s
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Topics

Chemistry in Daily Life and Industrial Applications

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