Fermentation efficiency can be negatively impacted by____________________?
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Answer: C. High concentration
Explanation
Excessively high sugar or reactant concentrations create severe osmotic pressure that dehydrates microbial cells. This profound osmotic stress damages cellular membranes and dramatically inhibits metabolic enzyme activity within yeast. Consequently, fermentation rates plummet when substrate concentrations exceed the optimal physiological threshold for microorganisms. Industrial fermentation relies on living microorganisms like yeast to convert sugars into alcohols and carbon dioxide. Microbial fermentation processes require carefully controlled environmental parameters including temperature, pH, and nutrient levels. High solute concentrations restrict water availability inside microbial cells, disrupting essential biological transport mechanisms.
Biofuel and beverage manufacturers carefully monitor initial mash sugar levels to prevent stalled fermentation batches. Optimizing nutrient feeding schedules maximizes overall ethanol yield and prevents premature yeast cell death. Industrial biotechnology engineers design fed-batch reactors to maintain ideal substrate concentrations throughout production cycles. The presence of air generally inhibits anaerobic ethanol fermentation pathways, forcing yeast into oxidative respiration instead. The absence of air is strictly required for alcoholic fermentation because oxygen promotes undesirable yeast biomass growth. Ammonium salts typically serve as beneficial nitrogen nutrients that actually enhance fermentation performance rather than hindering it.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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