• to preserve a raw food material that spoils easily (milk, meat, etc)
  • one of the oldest ways to preserve foods
• To produce new flavors and physical characteristics (color, texture, etc)
• Enhance nutritive value

Types of food fermentation

• grows fast, produces CO₂ and formic acid as well as lactic acid from lactose and galactose
• reduces the O₂ level, pH, and Eh
• more acid sensitive than lactobacilli
• unable to hydrolyze milk proteins

• grows in second
• needs CO₂/formic acid provided by ST
• hydrolyzes milk proteins, providing essential amino acids for ST
• produces lactic acid from lactose and galactose

• ST/LB produce exopolysaccharides (stabilizers)
• Acetaldehyde is produced (green apple flavor)
• Wheying-off due to acidification=common defect
• ST have been found that hydrolyze milk protein so LB may not be needed
• Bacteriophage to ST have increased

1. Malting
2. Mashing
3. Boiling worts and hops
4. Fermentation
5. Aging
6. Finishing

1. Barely grains are soaked in water and held at 16-21C for 5-7 days
2. Dry to stop sprout development
3. Can roast to generate color and flavor
4. Primary Role: a source of amylases and proteinases

1. Crushed Malt/malt adjuncts are added to water and the temp is slowly raised to 75C over a matter of hours-->produces worts
2. Primary Role: solubilize components of the malt and malt adjuncts; these provide nutrients from the yeast

1. Add hops to wort, boil for 2.5 hours, filter
2. Primary Role: Extract the hops, concentrate and sterilize the wort

1. Add SCe (ales) or SCa (lagers)
2. Incubate for 8-10 days at 18-21C (ales) or 4-7C (lagers)
3. Primary Role: Produce ethanol, CO₂, and flavor compounds

1. Stored at 0C for several months
2. Primary Role: precipitate yeast and protein=maturation of flavor

1. CO₂ produced during fermentation is added back and the beer is packaged
2. Primary Role: carbonate and package

1. Standardize the milk
2. Pasteurize it
3. Add starter culture (LL)
4. Add Chymosin
5. Cut the curd and drain the whey
6. Cheddar
7. Milk and Salt
8. Press into a block
9. Ripening

Lactococcus lactis

• Added as multiple strains
• Rate/extent of acidification=critical factor
• Converts lactose to L-lactic acid
• Control acid production by temp and salt
• bacteriophage is a concern

• A virus that infects bacteria
• Made up of DNA and protein
• Inactive-dormant but viable
• Survives pasteurization
• 1/1000 the size of bacterial cell
• pH tolerant
• Replicates very quickly

Non-Starter lactic acid bacteria (grow during ripening), usually Lactobacillus casei. Can have positive or negative impact on flavor

• a % of the mill/bill of metabolically active bacteria in every gram of ripening cheese are dying and releasing cell contents into the matrix
• these can allow other microbes to survive and produce bad flavors

1. Shred cabbage then mix in 2% salt solution
2. pack, cover seal
3. incubate (21-24C)
4. either refrigerate or can

• grow fast, pH limits its growth
• converts fructose to mannitol
• reduces O₂ level, pH and Eh
• produces acetic acid, and lactic acid from glucose

• grows second
• needs conditions provided by LM
• more acid-tolerant than LM
• produces lactic acid from glucose

1. soybeans (soaked and hulled) are boiled
2. Rhizopus oligosporus and the soybeans are mixed
3. Incubated 24-36 hr at 32C
4. Refrigerate

Tempeh

(the product and fermentation benefits)

• Product: soybean held together by mold myselium into white cake. nutty/mushroom flavor
• Benefits: destroys trypsin inhibitor, eliminates bean flavor, reduces cooking time from 6 hours to 10 min

general term for non-psychological adverse reactions to certain foods

• 2 types: immunological & non-immunological
• 30,000 ER visits each year
• 150-200 deaths each year

1. Metabolic:abnormal reaction from defect in metabolism of food component (lactose intolerance)
2. Idiosyncratic: adverse reactions due to unknown mechanisms (MSG, sulfites, aspartame)

• True food allergies
  • Antigen: protein in food
  • Production of specific antibodies by the body against the antigen
  • Antibodies cause a release of cellular chemicals which produce allergic reactions

• Cutaneous (hives, face swelling, eczema-like symptoms)
• Gastrointestinal (Nausea, vomiting, abdominal pain, diarrhea)
• Respiratory (runny nose, asthma, tightening/closing of throat
• Anaphylactic shock (shock reaction, drop/loss of blood pressure, organ failure, loss of consciousness, death)

Counts for 90% of allergies

Milk, eggs, wheat, soy, peanuts, tree nuts, fish, shellfish

• avoid commonly allergenic foods
• reading ingredient labels/asking at restuarants

• Allergens in foods retain allergenic potency even after heat processing
• if protein fraction is removed during processing, the product MAY be safe because allergen was removed

Food Allergen Labeling and Consumer Protection Act (FALCPA) of 2004

• FDA regulation effective January 1, 2006
• Regulations for all packaged food sold in US

• Dedication
• Separation
• Scheduling
• Clean-up or Sanitation