er from heavy crop years to light crop years.

This report presents the results of experiments conducted at the Alabama
Agricultural Experiment Station on methods of preserving pecans.

+Storage Troubles+

Some of the common pecan storage troubles are staleness, rancidity,
color changes, molding, and insect injury. Molding occurs only when the
product is stored in a moist atmosphere at ordinary temperatures. Insect
infestation usually results when the shelled kernels are held in
unsealed containers under ordinary storage conditions. Rancidity
develops during the summer months when the product is stored by common,
methods at ordinary temperatures.

Rancidity is probably the most common of pecan storage troubles; it has
been considered the most difficult to control. Rancidity is usually
preceded by general loss of flavor followed by staleness of kernels.
Color gradually becomes darker as the typical rancid condition develops.
These changes are associated with and caused by certain chemical
reactions that progress at a slow rate. The oils and fats are slowly
oxidized to aldehydes, ketones, and other chemical compounds (10), which
cause the undesirable aromas and flavors characteristic of the rancid
condition.

+Review of Previous Work+

The period during which pecans will remain free of rancidity and other
forms of spoilage varies considerably with storage conditions and other
factors. Common storage periods ranging from 3 to 12 months have been
reported. Wright (10) placed the common storage life at 3 to 5 months.
Blackmon (1) suggested 6 months as the maximum period. Medlock (11) was
able to keep them in edible condition for periods up to 12 months. The
wide ranges of time as observed by the different investigators are due,
no doubt, to storage conditions, variety, quality of the nuts, and
seasonal variations.

Cold storage was effective in preserving pecans for periods up to 2-1/2
years. Wright (10) reported effective periods of 13 to 30 months, and
Medlock (11) was able to keep them for more than 2 years. Shelled pecans
did not keep as long either in common or cold storage as the unshelled
nuts.

+Methods and Procedures+

Results of preliminary tests made at the Alabama Station in 1937
indicated that pecans kernels might be kept at common temperatures by
drying them in an oven and storing in sealed containers, which prevents
absorption of moisture from the air. Since storage tests reported by
other wo