Development Of Finger Millet Porridge Incorporated With Microencapsulated Ranawara (Cassia Auriculata) Corn Starch-Pectin Microparticles
Introduction
Diabetes is a prevailing chronic non communicable global public disease among the world. It is raising in to an epidemic level in both developed and even in developing countries. More than 180 million people are suffering from diabetes is estimated and it is predicted that this amount will be doubled in 2030. In the point of world scenario in the Middle East and North African regions diabetes has highest prevalence in adult (10. 9%) and in Western Pacific region has highest diagnosed adult population (37. 5%). In Sri Lanka the prevalence is in an early stage of epidemic. Reducing diabetes without any synthetic chemicals is a challenge and there is an increasing demand for formulated products by using natural herbal plants. Over 50% of all drugs are naturally originated.
To overcome this issue several varieties of plant extracts have been used in the traditional medicine. There are 400 number of plant species that has the anti-diabetic properties. One of the major plant that has the anti-diabetic properties is Cassia auriculata Cassia auriculata Linn (family: Fabaceae) commonly known as “Tanner’s Senna”, is a branched shrub contain bright yellow colour flowers appear in racemes at the end of the branches. Flowers are bisexual, Irregular, (nearly 5 cm across), the pedicels are glabrous and 2. 5 cm long. The racemes contain few-flowers short, erect, and flowers are gathered in upper leaves. This plant can be used to treat diabetes, eye troubles, rheumatism, leprosy and liver disorders. Flowers of crushed C. auriculata have been used to treat diabetes and white discharge in women. C. auriculata is a rich source of poorly soluble compounds and phenolic constituents such as Alkaloids, Phenols, Glycosides, Tannin, Saponins, flavonoids, flavonols.
C. auriculata flowers contain a bitter taste due to the presence of phytochemicals specially Tannins. Even though C. auriculata plant contain major beneficial properties people are reluctant to consume the flower extract due to its bitter taste. To mask the bitterness of C. auriculata flower extract microencapsulation technique can be used. It is the most promising technique that can be used along with spray drying as it can reduce the bitter taste of some chemical constituents and it can be incorporated in to functional foods.
Functional foods are foods that contain components that are nutrients or may not be nutrients but affects for the body functioning in a positive manner and affect positively for health. Finger millet (E. coracana) is a major source of nutrients that mainly provides Calcium, other minerals and fibre. Finger millet have low glycemic effect which is due to high fibre content. High fibre diets have high amount of complex carbohydrates that are slowly digested and release glucose slowly in to the blood stream. Therefore finger millet has a positive effect on health (finger millet).
Therefore finger millet can be taken as a functional food. There is a growing demand for plant extracted porridges such as herbal porridge of Asparagus falcatus L (Hathawaraiya), Soybean (Glycine max). These types of porridges are popular in traditional medicine in Sri Lanka. C. auriculata is commonly used plant for making porridges due to its strong therapeutic properties. In this research finger millet porridge was prepared by incorporating flower extract in to a matrix of corn starch and pectin through microencapsulation.
Corn starch and Pectin are Carbohydrates that are majorly used in food production systems. These polymers are ideal for making encapsulated micro particles due to the desired beneficial properties such as resistance to enzymes, making of stability in unstable molecules, strong gelling, film forming and binding ability. Starches contain amylose and amylopectin as major constituent. The relative composition of amylose and amylopectin are varying depending on the plant source. In corn starch it contain 28 wt % amylose. Depending on the amylose and amylopectin ratio starch exhibits binding, meshing abilities like mechanical properties and these properties can be used to make matrixes in microencapsulation. Even though starch-based matrix can be made, they are brittle, hydrophilic and have lack of processing and application abilities. To overcome these drawbacks starch can be mixed with different kind of natural polymers Pectin was used in order to make polymetric complex.
Pectin is a food-graded carbohydrate which is used as gelling and thickening agent in drug delivery systems. Pectin are used in pharmaceutical industry due to its biocompatibility, specific responses for specific pH. Pectin, with a degree of esterification (DE) greater than 50%, is known as high methoxyl (HM) pectin. HM pectin gels are stable at acidic (pH < 4. 0) pH, but dissolve at pH 7. 0 or above. HM pectin is ideal for pH-dependent delivery systems, due to its pH-sensitive behavior. Pectin can be also used as an emulsion stabilizer which is ideal for spray drying. Pectin is not digested immediately in the digestive tract, therefore it can used to increase transit time or can be used for targeted drug delivery.
Micro encapsulation is the process of coating or entrapping solid, liquid, or gaseous material in to another material or system. The encapsulating material may present as a wall, shell, matrix, membrane or it may be a carrier. The prepared microparticles may have single walled regular shaped core, irregular shaped core, multi layered core, they may have a matrix form. In matrixes core materials are dispersed throughout the micro particle. There are several microencapsulation techniques used in food industry such as spray-drying, spray-chilling, emulsion, coacervation, fluidized bed drying. But spray drying is the most popular microencapsulation technique than other techniques used in pharmaceutical industry due to the efficiency, low cost, continuous higher yield and one-step process.
