$2 Download Home and Farm Food Preservation 1915 – 257

HOME AND FARM FOOD

PRESERVATION

CHAPTER I

WHY FOOD SPOILS

Food spoils because of the growth and destructive

action of microscopic living organisms. They are com monly

termed " germs." The various methods of food

preservation are practically all based upon processes

that destroy these organisms or prevent their growth

and activity. Because they are microscopic and because

they are living organisms, we shall for convenience call

them " microorganisms."

1. Molds. The molding of food is a common phenom enon.

In some cases the food is completely spoiled; in

others, the decomposition is not sufficient to make the

product inedible; and in a few products, the growth of

certain molds is desirable.

The most prevalent mold and the one causing the most

damage is the " biue mold," otherwise known as " Peni cillium

expansum." It first appears usually as a white

cottony growth on fruits, cheese, cured meats, vegetables,

jellies, wine tanks, leather left in dark closets, and on

other articles favorable to its growth. This cottony

growth of mold threads is known as a " mycelium."

Later, the mold becomes " powdery " in appearance

and green or blue in color. This change in color is due to

the formation of billions of microscopic cells or " spores."

The spores are very light and easily detached. They

are carried by the air or other agencies from place to . . .