The flesh of the American olive consists of about 80 per cent of the fruit, and of this the solids average 38 per cent, oil 25 per cent, and protein 1.2 per cent.
In spite of the fact that olives have been used as a food from time immemorial, very little systematic analytic work seems to have been done on the whole fruit in the various stages of maturity and in determining the effect of the various treatments for the removal of the bitterness. Much of the analytic work has been devoted to analyses of the oil and to methods for determining adulteration. The methods followed in this country and abroad are not the same and the results are therefore not comparable. It seems strange that so old and so commercially important a fruit has not been investigated to the minutest detail.
It is stated that the olive on reaching full size increases in weight and oil content as it matures, the various stages being approximately determined by the change in color from green to yellow, red, and finally black. When, however, one finds analyses of typical fruit of one variety and from the same place which show the flesh of the green olive to contain 23.55 per cent; yellowish green, 20.37 per cent; red, 27.35 per cent; and purple to black, 24.89 per cent oil, it discounts the color value. Other available analyses show similar discrepancies between the chemical composition and the color test as indicative of maturity. Variation in composition occurs in the same variety of fruit grown in different places as well as in the different varieties and, as with other fruits, one is dependent upon the skill of the packer in selecting raw stock and in handling it in the process of manufacture, for the quality of the article received. It is only natural to expect that a product containing so much oil and subjected to the action of lye, might be greatly changed during its preparation. The data available, however, does not sustain this premise, but shows that very little change actually takes place.
LITERATURE
