FERMENTATION (BEER/CHEESE)

• Aerobic Fermentation


  Happens in the presence of oxygen, glucose is broken down into carbon dioxide, water, and ATP
• Anaerobic Fermentation


  Occurs without oxygen, involving the partial oxidation of glucose to generate energy, produces byproducts like ethanol, lactic acid, or other organics
• Saccharomyces cerevisiae


  • Predominant yeast strain in brewing, converting sugars into alcohol and carbon dioxide during fermentation
• Saccharomyces pastorianus


  • Utilized mainly in lagers, excels at fermenting at lower temperatures and yielding a cleaner, crisper flavor compared to Saccharomyces cerevisiae
• Lactobacillus and Pediococcus


  • Bacteria responsible for souring beer, producing off-flavors (diacetyl and lactic acid), and causing cloudiness
• Acetobacter spp.

  • Bacteria that turn beer into vinegar by converting alcohol to acetic acid
• Dekkera bruxellensis and Dekkera anomala

  • Yeasts that produce undesirable flavors (barnyard or fruity aromas), D. bruxellensis can be used in certain styles of beer, D. anomala is a spoilage organism
• Lactococcus lactis

  • Versatile bacterium responsible for acidifying the milk, lowering the pH, and separating the curds from the whey
• Streptococcus thermophilus


  • Heat-loving bacteria that works alongside L. lactis in many cheeses, especially those like mozzarella
• Lactobacillus helveticus


  • Bacterium responsible for the development of characteristic holes in Swiss and Emmental cheeses by producing gas bubbles during fermentation
• Lactobacillus casei


  • Bacterium that contributes to nutty and buttery flavors in cheese
• Lactobacillus plantarum


  • Bacterium that produces aroma compounds, contributing to the complex flavor profile of certain cheeses
• Penicillium roqueforti


  • Responsible for the blue veins and characteristic flavor of blue cheeses
• Geotrichum candidum

  • Contributes to the white rind and earthy flavor of Brie and Camembert
• Batch Fermentation

  All ingredients are added at the beginning, and the fermentation proceeds until completion. No further additions or removals occur during the process.
• Fed-Batch Fermentation


  Starts with an initial batch of ingredients, but additional nutrients are added throughout the process to extend the growth phase and increase product yield.
• Continuous Fermentation


  A steady-state process where fresh medium is continuously fed into the fermenter, and an equal volume of fermented product is removed simultaneously. This allows for continuous production with minimal downtime.
• Industrial Alcohol


  Refers to ethyl/ethanol (chemical formula C2H5OH), typically marketed by the gallon, weighing approximately 1.79 pounds, and comprised 95% C2H 6OH and 5% H 20 by volume, measured at 15.56°C.
• Making Industrial Alcohol


  1. Molasses, which has a high sugar concentration, needs to be diluted to around 10 to 14 percent sugar concentration, called the mash

  2. Mash serves as the carbohydrate substrate for yeast

  3. Ammonium salt and sulfuric acid are added to provide nutrients and maintain the optimal pH range for yeast activity, while magnesium sulfate may be added if deficient

  4. A portion of the selected yeast is cultivated separately
• Beer Making Process


  1. Malting: Barley grains are soaked in water for 2 days, then incubated for germination to activate enzymes and flavor components. Malt adjuncts are added to counteract darkening and destabilization.

  2. Kilning: Germinated barley seeds are heated slowly to 80°C to preserve amylase enzymes. Higher temperatures result in darker beer.

  3. Mashing: Grist (crushed barley grains) is mixed with warm water for 1 hour, allowing enzymes to hydrolyze starch into sugars. The resulting liquid, called wort, is obtained.

  4. Boiling of wort: Boiling extracts hop flavor, coagulates proteins, sterilizes the liquid, and concentrates the wort.

  5. Hops: Dried hop flowers are added for pungent aroma, coagulation of protein, bitter flavor, and preservation against bacteria.

  6. Fermentation: Yeast strains convert sugar into ethanol, CO2, glycerol, and acetic acid. Fermentation occurs at low temperatures for 14 days.

  7. Finishing, Ageing, Maturation, and Carbonation: Beer is stored at low temperatures for clarity and aging. Carbonation is achieved through cooling, clarification, filtration, and packaging.
• Cheese Making Process


  1. Milk Preparation: Milk is often pasteurized to eliminate harmful bacteria, ensuring food safety.

  2. Inoculation and Curdling: The milk is then inoculated with specific LAB cultures and rennet.

  3. Curd Cutting and Draining: The curd is cut into smaller pieces, allowing the whey to separate and drain.

  4. Salting and Pressing: Salt is added to the curd to inhibit unwanted bacteria, enhance flavor, and further influence the texture.

  5. Ripening: The cheese undergoes various biochemical and physical transformations under controlled temperature and humidity conditions.
• Significance of Lactic Acid Fermentation in Cheesemaking

  • Curd Formation: Lactic acid production by LAB lowers the pH.
  • Flavor Development: LAB contributes to the characteristic flavors and aromas of various cheeses.
  • Texture Formation: The type and amount of lactic acid produced by LAB, along with other factors, influence the texture of the final cheese.
  • Food Preservation: Lactic acid acts as a natural preservative.
• Contamination and Sterilization Issues in Industrial Fermentation
• Scaling Up Challenges and Considerations in Industrial Fermentation
• Control and Optimization of Fermentation Parameters in Industrial Fermentation
• Technological Advancements in Beer

  • Automation and Robotics, Genetic Engineering, Membrane Technology, Sensors and Monitoring Systems
• Technological Advancements in Cheese

  • Automation and Robotics, Genetic Engineering, Membrane Technology, Sensors and Monitoring Systems
• Importance of Quality Control in Industrial Fermentation
• Techniques and Methods for Monitoring and Ensuring Product Consistency in Industrial Fermentation
• Fermentation process


  • May now be observed in real-time
  • Leads to better control over the manufacturing process of cheese
• Sustainability and Environmental Impact
• Fermentation process optimization


  Minimizes waste and resource use, lowers energy consumption, and protects the environment
• Safety


  Ensuring contaminant-free products that meet regulations safeguards consumer health, avoids costly recalls and fines, and protects a company's reputation
• Continuous improvement through quality control data

  Refines the entire process for lasting efficiency and top-quality products
• Techniques and methods for monitoring and ensuring product consistency

  • Microbiological testing
  • Physicochemical analysis
  • Measuring product concentration, purity, and unwanted elements
  • SPC and GMP practices
• Comprehensive approach guarantees both safety and top-notch products
• Organizations that play a role in ensuring the safety, quality, and environmental impact of fermentative products

  • FDA
  • EMA
  • ISO
  • EPA
• Quality assurance in the beer industry


  • Assessing raw material quality
  • Rigorous sanitation
  • Ensuring healthy, pure yeast through proper storage, handling, and propagation
  • Process control and ongoing monitoring and adjustments
  • Training programs for proper handling, sanitation, and process control
• Quality control in the beer industry


  • Evaluating raw materials for quality
  • Maintaining strict sanitation standards
  • Ensuring precise yeast management for purity and health
  • Process control for optimizing yeast activity and product characteristics
  • Training programs for handling protocols, sanitation procedures, and process control techniques
• Quality control in the cheese industry

  • Preventive measures
  • Rigorous testing for freshness and composition of raw milk
  • Stringent hygiene practices for facilities and staff
  • Well-designed facilities
  • Training programs
  • HACCP system for identifying and managing potential hazards