Food Chemistry Quiz

Which of the following is a functional property of carbohydrates in food chemistry?

• Retrogradation of starch

• Rancidity of lipids

• Enzymatic browning

• Gram-staining

Answer explanation

Retrogradation of starch is a functional property of carbohydrates, involving the reorganization of starch molecules upon cooling, affecting texture and digestibility. The other options relate to lipids or are unrelated.

What is the primary role of proteins in food post-mortem processes?

• Retrogradation of starch

• Tenderization of muscles

• Enzymatic browning

• Growth kinetics of microorganisms

Answer explanation

The primary role of proteins in post-mortem processes is the tenderization of muscles. Proteins break down during aging, leading to a more tender texture in meat, which is crucial for quality in food preparation.

Which pigment is responsible for the green color in plants?

• Carotenoids

• Anthocyanins

• Chlorophylls

• Tannins

Answer explanation

Chlorophylls are the pigments that give plants their green color, as they absorb light primarily in the blue and red wavelengths while reflecting green light. This is essential for photosynthesis.

Which of the following is an example of a fermented food or beverage?

• Milk

• Vinegar

• Egg

• Fish

Answer explanation

Vinegar is a fermented product made from the fermentation of ethanol by acetic acid bacteria. Unlike milk, eggs, and fish, which are not fermented, vinegar is a clear example of a fermented food.

What is the significance of gram-staining in microbiology?

• It identifies the nutritional value of food.

• It classifies microorganisms based on their cell wall properties.

• It measures the protein efficiency ratio.

• It determines enzymatic browning.

Answer explanation

Gram-staining is significant in microbiology as it classifies microorganisms based on their cell wall properties, distinguishing between Gram-positive and Gram-negative bacteria, which is crucial for diagnosis and treatment.

Which microorganism is commonly associated with food spoilage in milk products?

• Salmonella

• Bacillus

• Escherichia

• Aspergillus

Answer explanation

Aspergillus is a mold commonly found in dairy products, leading to spoilage. Unlike Salmonella and Escherichia, which are bacteria, or Bacillus, which can also spoil food but is less common in milk, Aspergillus is specifically associated with milk spoilage.

What is the role of coenzymes in enzymatic reactions?

• They inhibit enzymatic browning.

• They act as catalysts in biochemical reactions.

• They provide energy for microbial growth.

• They classify microorganisms.

Answer explanation

Coenzymes are essential for enzymatic reactions as they assist enzymes in catalyzing biochemical processes. They often act as carriers for chemical groups or electrons, facilitating the reaction without being consumed.

Which of the following is an essential fatty acid required in a balanced diet?

• Oleic acid

• Linoleic acid

• Palmitic acid

• Stearic acid

Answer explanation

Linoleic acid is an essential fatty acid that the body cannot synthesize and must be obtained through diet. It plays a crucial role in various bodily functions, unlike oleic, palmitic, and stearic acids, which are not essential.

Which of the following is NOT a principle of food processing?

• Thermal processing

• Irradiation

• Controlled atmosphere storage

• Fermentation

Answer explanation

Controlled atmosphere storage is a method of preserving food rather than a processing principle. The other options—thermal processing, irradiation, and fermentation—are all recognized methods of food processing.

What is the primary method used in oil processing?

• Milling

• Solvent extraction

• Pasteurization

• Drying

Answer explanation

The primary method used in oil processing is solvent extraction, which efficiently separates oil from seeds or other materials using solvents, making it the most common technique in the industry.