Fats and Oils
Pages 1-14
DOI: https://doi.org/10.1094/9780913250907.001
ISBN: 0-913250-90-2
Abstract
Topics Covered
- Functions in Food Systems
- Functions in Processing
- Sensory Functions
- Nutrition
- Functional Properties
- Chemical Structure and Fat Properties
- Functional Characteristics
- Chemical Reactions
- Fat and Oil Sources and Compositions
Introduction to Chapter
Fats and oils have always been an integral part of the human diet. Of prime importance is their role as a calorie-dense food component—they have nine kilocalories per gram versus four kilocalories per gram for starch or protein. The present-day concern with obesity and high fat content is actually a historical and geographical anomaly. For the greater part of human existence, the search for adequate food energy sources occupied a large segment of time, and fat was a prized component of the diet.
The varied cultural preferences for traditional food fats spring, in part, from geographic roots. In colder climates (e.g., northern Europe) most fats were derived from animal sources, and lard, tallow, and butter were the main fats. Thus, plastic shortenings were used in most culinary recipes that were brought to North America by northern European immigrants. In warmer climates (e.g., Mediterranean countries), vegetable oils, such as olive and sesame seed oils, were the predominant available fats; the cuisine of these countries reflects this difference. More recent times have seen a cross-cultural interchange in this respect, but to some extent the traditional patterns still exist.
It is difficult to adequately condense many large tables of data on the availability and consumption of fats and oils, but one example can be instructive. The annual per capita (adult) consumption of fats and oils in the United States, as of the late 1980s, was approximately:
- 24 lb of salad and cooking oils
- 23 lb of bakery shortening and frying fats
- 20 lb of fat from meat, poultry, fish, and cheese
- 13 lb from butter, margarine, and other miscellaneous sources
This total of 80 lb per person per year represents about 38% of the calories in the diet. With the recent push to reduce this number to 30%, the above numbers will probably decrease, but the proportions will likely remain about the same.
Commercial (as opposed to home) use of fats and oils accounts for most of the shortening and frying fat category, some part of the salad oil category, fats for margarine production, and many of the miscellaneous items (confectionery coatings, oil-based whipped toppings, coffee whiteners, etc.). The specifications for these fats and oils are generally more stringent than for fats and oils used in the home. Commercial equipment and processes are more sensitive to variations in fat characteristics; the specified properties for the finished product are more narrowly defined; and compensating for ingredient variation takes longer than in home cooking. The people responsible for efficient operation of such a plant must understand how fat and oil properties affect production and product characteristics and how to write and enforce specifications for these raw ingredients, so that the outcome is satisfactory both to the consumer and to the owners of the plant.