Extraction and Utilization of Pectin from Purple Star-Apple (Chrysophyllum cainito) and African Star-Apple (Chrysophyllum delevoyi) in Jam Production


Austin J Nutr Food Sci 2014;1(1): 1003.

Extraction and Utilization of Pectin from Purple Star-Apple (Chrysophyllum cainito) and African Star-Apple (Chrysophyllum delevoyi) in Jam Production

Nwosu JN, Udeozor LO, Ogueke CC, Onuegbu N, Omeire GC and Egbueri IS

Department of Food Science and Technology, Federal University of Technology, Owerri, Nigeria

*Corresponding author: : Nwosu JN, Department of Food Science and Technology, Federal University of Technology, Owerri, P.M.B 1526, Owerri, Imo State, Nigeria

Received: December 17, 2013; Accepted: December 27, 2013; Published: December 28, 2013


The pectin of African star apple (Chrysophyllum delevoyi) and purple star apple (Chrysophyllum cainito) were extracted using the alkaline hydrolysis method to produce pineapple jam. The jam so produced was used to compare with that of synthetic pectin which was used as a standard. From the analysis of both sensory evaluation and chemical analysis, the result showed that viscosity increased with addition of pectin to jam from 2.25– 3.01 Cp from peels of purple star apple and synthetic pectin respectively. The pH of the jam samples was generally acidic ranging from 3.58 to 3.81. The total dissolved sugar ranged from 55 to 78o Brix. The total titrable acidity varied from 27% to 34% and the ash content ranged from 3.8% to 4.2%; the ascorbic acid content varied from 8.2% to 9.2%mg/1 00g. Finally the total solid varied from 66% to 73%. Experimental result statistically, showed that there was significant difference (p≤0.05) on appearance, spread ability, mouth feel, taste and overall acceptability. However, no differences existed for texture and aroma at p≥0.05.Thus, these fruits could be successfully utilized in the production of fruit preserves.

Keywords: Purple star apple; African star apple; pectin; pineapple jam; extraction; performance.


Purple star apple (Chrysophyllum cainito), commonly called “Udara beke” in Anambra State, “Udara Oyigbo in Imo state, “agbulag” in the North, is one of the minor fruits of the family Sapotaceae meaning star apple or gold leaf tree [1]. It has acquired a moderate assortment of regional names. In Spain, it is usually called “caimitto” or “estruella”; in France, generally, “cainute” or “caimtier”. In Colombia, it is called “caimo” or “caimo morado” (purple variety). In Argentina, “aguay” or “olivoa” [1].

African star apple (Chrysophyllum delevoyi) popularly known as Agbalumo among the Yorubas, Agwaluma among the Hausas and Udari among the Efiks and Ibibios in southern Nigeria is a fruit that is commonly eaten raw in the study area. It is a large berry that contains up to five seeds that are flat in shape. The plant belongs to the family sapotaceae. The leaves of the plant are alternate and nearly evergreen elliptic, slightly leathery. The fruit could be ellipsoid, round or pear shaped. It has a milky sweet pulp that houses the seeds. When the fruit is cut transversely it appears like asterisks in the central core or like the pointed stars. This is the origin of the name of the fruit as “STAR APPLE”. The fleshy fruit is eaten raw by most people and relished by many others.

Purple star apple, when matured and ripe was found to contain 25.95% calories, Moisture content of 33.142%, 0.901% protein. It has carbohydrate content of 5.67%, fibre content of 1.276%, 0.278%Ash, 6.6%calcium, 8.5%phosphorus and 0.262% iron. It has a reasonable content of vitamins that is 0.015% carotene, 0.031% thiamine, 0.0154% Riboflavin, 0.52% Niacin, 0.58% Ascorbic Acid. The amino acid content includes 1.547% trypthophan, 0.77% methionine and 0.851% Lysine. It has some amount of saturated fat about 0.90%. The proximate composition of African star apple includes moisturecontent: 66.7%, crude fat: 9.38%, ash: 2.12%, protein: 5.66%, crude fibre: 4.5%, carbohydrate: 78.34%; ascorbic acid: 19.68%; total metabolisable energy: 420.42 kcal as reported by [2].

Based on its widespread nutritional composition, it could be used in many areas of food. The skin which constitutes about 33% of the entire fruit could be a source of pectin which is used as gelling agent, thickener and as a stabilizer in most food and drug industries [3], thus a means of managing waste. The ripe fruit, preferably, chilled, may be cut in halves and the flesh spooned out, leaving the seed cells and core, a combination of the chopped flesh with that of mango, citrus, pineapple, other fruits and coconut water, is frozen and served chilled as Jamaican fruit salad [4]. It could be blended and squeezed to extract juice and served with ice, orange juice or gelled to produce jam or jelly [5].

Despite its food benefits, Purple star apple is highly perishable due to its high moisture content which ranges from 32–33% [1]. It is susceptible to microbial action as it can harbour a wide range of microorganisms due to the high moisture content [6,7]. It is a very seasonal and semi–wild fruit that produces during the dry (Harmattan) season [1]; it is therefore not available all year round. It is very sugary i.e. high in glucose. Due to its high sugar content, non–sugar loving consumers and diabetic patients will not readily demand the fruit for health purposes.

Also the problems associated with African star apple include that of seasonability and perishability. Owing to the above mentioned problems, the fruits could be converted to other forms to meet thedemand of consumers of all types. These forms are preserves, concentrates, wines, extraction of pectin from the fruit, which is a stabilizer. This will go a long way to solve the problems of seasonal glut, rapid spoilage, and unavailability in regions of poor and unfavourablecondition for growth of the fruits, storage and transportation, thus making the fruit not to go into extinction and increasing its utilization in many food formulations.

Pectin refers to the water soluble pectic acids with various degree of methylation (methyl ester content) and degree of neutralization which are capable of forming gels with sugar and acid in a suitab le condition [8]. It is a purified carbohydrate generally obtained from the acid extraction of the inner portion of citrus fruit peels and apple pomance [9]. As a polysaccharide it is an adhesive/firming agent in many fruits and vegetables and therefore could be used as a gelling agent in Jam and jellies [10,11].The objective of this research worktherefore is to extract pectin from purple star apple and African star to compare its performance with commercial pectin on pineapple jam.

Materials and Methods

Matured, semi–ripe purple star apples, (Chrysophyllum cainito) used for this research work were obtained from St. Thomas Acquinas Catholic Church, FUTO. Matured ripe African star apples (Chrysophyllum delevoyi) and fresh pineapples were purchased from Ekeonuwa market in Owerri Town, Imo State, Nigeria. The chemicals used were of analytical grade and were obtained from the Department of Food science and Technology, Federal University of Technology Owerri. The equipment and other materials used were obtained from the Departments of Food science and Technology and Crop science and Technology, Federal University of Technology Owerri, Imo State, Nigeria.