Transcript Food and Microbes

Food and
Microbes
Test 6 Notes
CANNING
 is the process of heating the product
at a specified temperature for a
specific length of time (pasteurizing)
 vacuum sealing the pasteurized food
in special glass jars
 fruits, vegetables, meats, seafood,
and some prepared foods.
 Home Methods VS Industrial Methods
FREEZING
 is the process of chilling foods to
at least 0°F.
 It can be used with all foods
 True freezing is not possible in
the freezer compartment of your
refrigerator where the
temperature is typically much
warmer, between 10°F to 32°F.
 Easy method
DRYING
 is the process of dehydrating
foods until there is not enough
moisture to support microbial
activity.
 It can be used with most foods
 Several different techniques,
relatively easy to do and require
no special equipment.
 Meals-Ready-to-Eat (MRE)
FERMENTING
 is the process of encouraging the
growth of “good bugs” to inhibit
the “bad bugs” that can spoil food.
 It can be used with many types of
foods
 Produce a wide range of products
such as wine (from grapes),
sauerkraut (cabbage), cured
sausage (meat), and yogurt (milk).
 produced without any special
equipment.
PICKLING
 is the process of soaking food in a solution
containing salt, acid, or alcohol.
 It can be used with most foods
 Most methods require no special
equipment.
 However, pickled foods can be unsafe if
prepared carelessly or stored at room
temperature.
 Pickling is often combined
with another method, such as
fermenting, canning, or just
refrigerating
CURING
 is similar to pickling, and uses salt,
acid, and/or nitrites.
 It is used for meat and fish.
 Simple, modern curing methods often
reduce the amount of salt and
nitrites, which may require that you
refrigerate or freeze the final product.
 Some curing methods also
employ a secondary process
such as fermenting,
smoking, or sealing.
SMOKING
 is a complementary process to
curing that improves flavor and
appearance, and can also act as
a drying agent.
 Smoked meats are less likely
to turn rancid or grow mold
than unsmoked meats.
SEALING
 is a process of covering food to
keep out air, which delays (but
does not stop) the activity of
spoilage organisms.
 It is used primarily as a
complementary process to other
methods such as drying or
freezing.
 Both fat sealing and vacuum
sealing methods are relatively
easy.
Importance of Bacteria
 It would be impossible to make cheese without a starter
culture. As the culture grows in the milk, it converts the
sugar lactose into lactic acid, which ensures the correct
level of acidity and gives the cheese it
 In yogurt and other fermented milk products, the culture is
responsible for the taste and texture of the final product.
 Probiotic cultures have become popular in dairy products
because of their health benefits
 Meat starter cultures are used to make dried, fermented
products such as salami, pepperoni, chorizo and dried ham
 Yeasts are responsible for the fermentation process
which produces alcohol in wine.