Spice Crops Processing of its Products and By-Products
The antiquity and uses of spices has long been established and could be traced back to ancient times when it was not only used as condiment but was widely employed as essences, perfume, cosmetic and medicine. The increasing demand for spices dates as far back as 1492 when Columbus was not only looking for gold but for a short cut to the Indies in search for spices.
Spices are natural products widely accepted by consumers. It covers a multiplicity of plant parts such as root, bark, stem, bud, seed or fruit which have a variety of fragrance, aromaticity and pungency. They are largely valued for the contents of their secretory tissues giving rise to essential oils, oleoresins, and oleogum resins, most of which are highly aromatic and which bequeaths an aroma and flavor to food with an undeniable psychological as well as physiological effect. It exerts peristalsis in the digestive system so that food is more utilized by the body. Foodstuffs are therefore made more acceptable and easily digestible.
Among the spices which are found or cultivated in the country are: pepper, onion, annatto, tumeric, bay leaf (laurel) cloves, cinnamon, nut meg (mace), capsicum, anise, dill, oregaano, coriander and mint. There is a dearth of information on research studies on this very popular commodity. Very little information too, is available on their local processing and in- use application.
Most spice processing usually take place in the primary growing areas between harvesting and marketing. It involves two basic operations: drying and cleaning. Additional operation may include storage period to allow for fermentation or other biological processes to take place. In developed countries, the term spice processing refers to further series of operations in which the flavor and aromatic substances are removed from the dried matric and incorporated as essential oils or oleoresins ending with whatever products maybe demanded by the food processing industry. These include essential oils, alcoholic extracts, oleoresins and blended concentrates made from these.
As these are usually necessary to prepare diluted versions for direct incorporation into food products. These may be done by:
- a. dissolving the concentrate in alcohol, propylene glycol or some other appropriate solvent to make an essence.
- b. dispersing the concentrate onto a dry carrier such as salt, dextrose or starch as appropriate to make a dry dispersed spice.
- c. emulsifying the concentrate with gum arabic or one of the modified starches followed by spray drying to give an encapsulated spice.
Spice processors are actively engaged in reappraising their products and processing methods with growing concern on problems of quality control.
Producers aware usually careful to avoid loss of essential oil in the drying and preparation of spices for the market, particularly where the essential oil is contained in cells near or in the epidermis, as for example in leaf spices. The highest concentration of essential oil is believed to be reached at the time when the plants come to bloom. It is at this time that harvesting is carried on.
Spices are grown in many parts of the world. It may be dried indoors or outdoors according to climatic condition. Care is essential in drying. Over exposure to air and sunlight can cause loss of essential oil, and so do too much artificial heat and too rapid drying. When artificial heat is employed, it must be carefully controlled and effectively circulated, beginning with a moderate degree of heat and gradually increasing the temperature to the permissible maximum.
When the whole spices reach the spice merchant, some are set aside for sale as such. Some will be reduced to powder to meet the needs of consumer. Some spices require being brought to suitable size for milling as in the daze of barks. Among the machines which could be used for grinding spices are hammer mills, roller mills, attrition mills, and shifting but employ a combined grinding and shifting machine.
Some essential oils are volatile and also, since grinding creates a large area of exposure, ground spices must therefore be kept tightly capped in their containers when not in use; or else quality and flavor will soon be dissipated. Whole spices naturally are less prime to loss of their volatile constituents, nevertheless, they should also be kept in closed containers for the same reason.
Spice Crops Problems Associated with Spices
The physical form of spice is normally a fine powder, although some may be obtained in a rather coarse “rubbed” form. With modern technological approaches to food seasoning aimed at consistent products of high quality, the many disadvantages associated with the use of good spice is now unquestionably accepted. Flavor is an important factor in saleability which in turn is independent upon appearance and keeping qualities of the meat products. Since spices can actually detract from fresh appearance and shorten shelf-life, this has been a subject of considerable research abroad.
Ground spices are carriers of considerable levels of bacteria. This results from low standards of hygiene associated with harvesting, open-air drying, storage and so on. Cleaning consists mainly of screening to remove larger foreign bodies (stones, wood, earth) followed by either airblowing or water washing to remove dust. When the spices are introduced into a meat product, high bacterial count can result in its rapid deterioration, especially in a fresh product such as sausage. The high bacterial and spore content of many pure and mixed spices is a technological and hygienic problem for food manufacturers.
Sterilization methods are often employed to reduce bacterial loading. The most effective method is exposure to ethylene oxide which denaturates the bacterial cell wall. Alternatives such as irradiation are not acceptable. Besides, at effective levels to achieve sterilization, the spice flavor is altered and other factors may lead to development of off-notes. If the technique of gas sterilization is correctly handled, then ethylene oxide residues are minimal and no change in the flavor of lathe spice can be observe.
Certain spices have been shown to contain lipases, which are enzymes capable of splitting fat molecules. These enzymes remain inactive which the cell structure within the spice is intact. The grinding process however, destroys much of the structure, thereby releasing the enzymes. When the spices are added to fat containing foods such as meat, the lipases react to form fatty acids giving a rancid odor and flavor to the product.
Quality Variations and Speckling
Being natural products, spices are subject to variations in flavor strength and quality. Factors such as climatic differences, methods of cultivation and drying methods make the task of minimizing variations difficult. Certain variations inherent in this materials must be accepted and this requires consideration in the establishing of a consistent finished product.
Ground spices present themselves as dark specks in the melat product which produces a dulling effect on the natural color.
For more information contact:
Dept. of Science and Technology
Rm. 303 DOST Bldg., DOST Complex,
Gen. Santos Ave., Bicutan, Taguig City 1631
Telephone Nos: (632) 837-20-71 to 82