For hundreds of years, Americans have used pecans in many foods, but use of the pecan has quickly spread throughout the world. Sue Taylor reports.
With a history tracing back to the 16th century, the pecan the only major tree nut that grows naturally in North America is considered to be highly desirable nut. Originating in central and eastern United States and the river valleys of Mexico, pecans were selected for many food uses because the trees were accessible to waterways and the nuts easier to shell than some other North American nut species. Some historians believe that Native Americans were the first to cultivate pecan trees (in fact, apecan' is a Native American word of Algonquin origin that was used to describe aall nuts requiring a stone to crack').
The first pecan trees in the United States are said to have been planted in Long Island, New York in 1772. The popularity of pecans quickly spread down the Atlantic Seaboard, as pecan trees were planted in the gardens of well-known Easterners such as George Washington (1775) and Thomas Jefferson (1779). Commercial production of pecans began in the early 1800s and pecans have thrived ever since. Today, there are several hundred varieties of pecans being grown, with the majority of the world's pecan production (about 80 per cent) coming from the United States. In the US alone, the pecan harvest has increased from 2.2 million pounds in 1920 to nearly 340 million pounds in 2001. Harvesting of pecans usually begins in October and can extend into the late winter of the following year.
Pecans have a distinctive flavour and nutritional benefits that make them an attractive nut for a variety of uses by the food processing industry.
Once the pecans are harvested using mechanical harvesting techniques, they are primarily destined for a shelling operation. In fact, since 1948, more than 80 per cent of pecans sold have been ashelled' (the shell has been removed), but this was not always the case. The pecan industry did not begin its rapid growth until the mid-1920s when commercial equipment used for washing, separating faulty meats and shells, cracking, drying and packaging pecans was developed.
Today, some shelling plants operate year-round, while others operate on a seasonal basis (most commonly the fall months). Large plants can have as many as 14 cracking machines with a capacity of 150000 pounds a day and 30 million pounds each season. Pecans are conditioned or moistened before cracking/shelling to protect the internal meats and increase the shell's stability. After cracking, the meats and shells are separated by a series of shaker screens and then sized. Shelled pecans are then dried slightly to reduce moisture and maintain quality.
Once shelled, the pecan meats are graded according to US Department of Agriculture (USDA) specifications. This includes an inspection for freedom from dust, dirt and other defects, uniformity of size and colour, firmness and amount of meat in proportion to size. There currently are five USDA grades for shelled pecans: p US No1 halves. p US Commercial halves. p US No1 pieces. p US Commercial pieces. p Unclassified.
Shelled pecans also can be purchased in several forms, including halves, pieces, granules and meal. Food processors should check with a pecan sheller/supplier to help determine the size most appropriate for a particular food product.
Pecan Halves
# Halves Per Pound
Mammoth (largest) 250 or less
Junior mammoth 251300
Jumbo 301350
Extra large 351450
Large 451550
Medium 551650
Topper (smallest) 651 or more
Pecan Pieces p Mammoth (largest). p Extra large. p Large. p Medium large. p Medium. p Medium small. p Small. p Midget. p Granules. p Meal (smallest).
Pecans are a natural, high-quality, high fibre, cholesterol-free food with significant nutritional value. Pecans contain more than 19 vitamins and minerals, including vitamin A, vitamin E, folic acid, calcium, magnesium, phosphorus, potassium, copper, manganese, several B vitamins and zinc. The fat in pecans is primarily unsaturated fat (nearly 60 per cent is monounsaturated and 30 per cent polyunsaturated) making about 90 per cent of the fats (oils) in pecans of the aheart-healthy', unsaturated variety. Pecans also contain a significant amount of linoleic acid, a polyunsaturated fatty acid that the body requires to function properly. In addition, most of the monounsaturated fat is oleic acid, the type found in olive oil. Beneficial plant sterols, which are widely touted for their cholesterol-lowering ability, have also been identified in pecans in concentrated amounts. Scientific research has shown that the consumption of pecans can play a positive role in maintaining good health, ranging from preventing heart disease and diabetes to being an aide in weight loss efforts.
As for the specific characteristics of pecans, their full flavour is compatible with that of most foods and can add a rich, meaty taste. The distinct sweet odour of pecans is found primarily in pecan oils, which enhances the appeal of many finished products.
The crunch of pecans can add a delicious contrast and makes them suitable for just about any processed food. Textures can vary, depending on the pecan product chosen (eg, pecan halves offer a crisp bite, while pecan meal offers no bite at all). Regarding colour, pecans are classified according to the predominant colour of their skin. Colour classifications range from alight' to alight amber' and adark' to adark amber', as specified by USDA standards.
Shelled pecans should be protected from moisture, light, heat and oxygen to preserve freshness. Using the appropriate containers, they can be stored under refrigeration for about nine months (below 35oF and 70 per cent relative humidity is preferable) or frozen at 0oF for up to two years. Airtight containers are best for storing pecans under refrigeration, while sealed plastic bags are best when freezing. If handled properly, pecans may be refrozen numerous times without any damage or quality deterioration provided they are properly tempered. Frozen pecans should be tempered by gradually raising the temperature in a humidity- and temperature-controlled environment to minimise condensation and the resulting risk of mold. (Significant air movement around the pecans can also speed up the tempering process and helps minimise the possibility of condensation problems.) After permanent removal from cold storage, the quality of pecans will remain good for about two months at normal room temperature.
Like other nuts, pecans can readily absorb moisture, gases and odours from the atmosphere, which come from surrounding goods, musty storage areas or petroleum-based products. For this reason, pecans should be stored separately or with non-odorous dry products whenever possible. Ammonia should also be eliminated from the storage area, as traces of ammonia can cause blackening of the seed coat over time. Packaging pecans in a sealed liner or gas-proof container can prevent changes caused by gases or odours.
In summary, pecans can awork magic' in a wide range of processed foods. Not only are pecans perceived as being a high-quality nut, they add exceptional nutritional value to foods in the form of unsaturated fat, fibre, protein and other key nutrients. A variety of pecan products are available to fit any food processor's individual need.
Sue Taylor, MS, RD, is with National Pecan Shellers Association, Atlanta, GA, USA. www.ilovepecans.org
