NUFS 363 Final

F = D_r(a-b)

• D_r = D at 121^oC
• a = initial population
• b = final population

• Microwaves
• UV
• Gamma Rays
• X-rays
• Cold Pasteurization
• PEF (Pulsed Electric Field technology)
• HHP (High Hydrostatic Pressure)

Radurization: low dose, quality enhancement, like pasteurization, reduction of spoilage organisms

Radicidation: equivalent to pasteurization, reduction of pathogens

Radappatization: equivalent to sterilization, high dose, medical equipment

• - Minimize health risk
• - Improve nutritional quality
• - Enhance storage quality
• - Improve sensory properties

Amount of undissociated acid

Propionibacterium shermanii

• Nitrous acid
• pKa 3.4

• Converted to nitrite
• Cell proteins react with nitrite to form iron-nitric oxide complexes
• Destruction of iron-sulfur enzymes
• Growth inhibited

Nitrosamines

Nitrite + free amino group = potential carcinogen

Cultured celery extract

Destroys vitamin B1

• Lantibiotics
• Small, heat stable peptides
• Extensive post-translational modifications
• Unusual AAs (lanthionine)
• Ribosomally synthesized

• Small, heat stable, hydrophobic peptides
• Limited post-translational modifications

Large, hydrophilic proteins

Circular bacteriocins

• Structural gene(s)
• Immunity gene

• Transport genes
• Modification genes
• Regulation genes

• Nicin
• Affects cell membrane = pores
• Inhibits C. botulinum outgrowth
• Reduces canning process & heating time

• Miocin
• Listeria monocytogenes

Cultured corn syrup

• Ferment carbs to lactic acid
• Gram (+), non-sporulating, nonmotile
• Grow anywhere with right pH and carbs

• Homofermentative (obligate)
• Heterofermentative (obligate and facultative)

• Lactobacillus delbrueckii subsp. bulgaricus
• - strong proteolytic activity, provides AAs for Staph

• Staphylococcus thermophiles
• - limited proteolytic activity, provides flavour

Propionic acid, CO₂, acetic acid

Nutty flavour, holes in Swiss cheese

• Rapid fermentation of lactose
• Proteinase activity
• Phage resistance
• Production of inhibitory compounds

• Conversion of biomass to fermentable sugars
• Fermentation
• Recovery of alcohol & product formation

• Unfortified: beers, wines
• Fortified: ports, sherry
• Distilled spirits: whiskey, gin, vodka, rum

• Humulus lupulus
• Flavour & preservation

Germinated barley, activates amylases

• Identification of strain (latin name/strain ID)
• Quantitative declaration (CFU/serving)
• Ingredient list (common name/bacterial culture)

• Antibiotic resistance
• Production of antibiotics
• Pathogenic potential
• Metabolic activities (D-lactate production, bile salt deconjugase activity)

BILE SALT DECONJUGASE, IT HAUNTS ME

• Resist gastric activity, hydrolysis
• Ferment by intestinal microflora
• Stimulate growth/activity of selected intestinal bacteria (ProB's and "good" microflora)

• Normalized intestinal microbiota
• Stimulate immune system
• Metabolic effects (eg. lactose hydrolysis)

• Microbial counts: next day results, more accurate
• Bioluminescence: same day results, measures ATP, less accurate

• Few particles needed
• Shed in stools of infected individuals
• Need living cells to replicate
• Stable outside of host/acid-resistant

• Projectile vomiting, abrupt onset of non-bloody diarrhea, abdominal cramps, headaches, etc. 
• Resolves within 24-48 hrs (24 hr flu)

• Jaundice, fever, nausea, anorexia, malaise, dark urine, abdominal discomfort.
• Lasts less than 2 months

• Vomiting, non-bloody diarrhea (watery, explosive), fever, dehydration, electrolyte imbalance
• Affects mostly children

• Prevent contamination
• Thermal processes
• Sanitation (hand sanitizers don't count)

• Giardia lamblia
• Cryptosporidium parvum
• Cyclospora cayetanensis
• Toxoplasma gondii
• Trichinella spiralis

• Protozoan
• Waterborne
• Livestock & foodborne (poor hygiene)
• Highly contagious
• 1 cyst dose
• Asymptomatic carriers
• Diarrhea 1-2 wks

• Contaminated drinking water
• Raw/undercooked food contaminated with oocysts
• Onset 5-21 d
• Severe diarrhea, cramps, headache, nausea, vomiting (fever, coughing)
• Long exposure in immunocompromised = death
• MUNICIPAL WATER

• Worldwide
• Transmitted through water, food, person
• Onset 2-11 d
• 1 cyst dose?
• Sever diarrhea
• Sometimes weight loss, bloating, stomach cramps, nausea, vomiting, etc.

• Obligate intracellular parasite
• From cat feces (only known host)
• Severe illness in fetus'

• Undercooked pork/wild game
• 1 larvae dose
• Freeze to control
• 1-2 d nausea, diarrhea, vomiting, fatigue, fever, discomfort
• 2-8 wk headaches, fever, chills, cough, eye swelling, muscle pain, constipation, diarrhea, etc.