Morphological characteristics, nutrient composition and carrageenan quality of red seaweed, kappaphycus alvarezii, from Sabah and East Kalimantan

• Main Author: Irman Irawan
• Format: Thesis
• Language: English; English
• Published: 2020
• Subjects: TX341-641 Nutrition. Foods and food supply
• Online Access: https://eprints.ums.edu.my/id/eprint/40892/1/24%20PAGES.pdf; https://eprints.ums.edu.my/id/eprint/40892/2/FULLTEXT.pdf; https://eprints.ums.edu.my/id/eprint/40892/
• Institution: Universiti Malaysia Sabah

This research aims to compare the waters condition in Sabah and East Kalimantan, to compare the different drying methods of Kappaphycus alvarezii , to analyse the physical and chemical properties of carrageenan which has been extracted from Kappaphycus alvarezii harvested from Sabah, Malaysia and Bontang, Sangatta, East Kalimantan, Indonesia and to examine the application of carrageenan in ice cream. This research employed two seaweed drying methods, namely direct sun-drying and the sauna or steam drying method. The carrageenan extraction process was carried out in a water bath equipped with a stirrer with a constant speed of 275 rpm. Furthermore, the extraction process was conducted with a constant ratio of seaweed weight to the volume of distilled water (20:500 g/ml) at 70oC for an hour. The extract was precipitated in 6% potassium hydroxide (KOH), 0.2% potassium chloride and ethanol which increased the speed of carrageenan formation. They were dried in an oven at 60oC for 24 hours. The results showed that the direct sun-drying method showed a faster drying rate of 60-70% decrease in water content after being dried for 6 (six) times, whereas the sauna drying method produced clean and white seaweed. The proximate carrageenan test results showed that the highest moisture content was seaweed from Bontang using sauna method B3 (10.35 ± 0.76), the highest fibre was B1 (15.67 ± 0.60), the highest viscosity was in treatment seaweed from UMS in Salakan Island using sauna method B2 (28.47±1.03), the highest ash content was seaweed from Sangatta using direct sun-drying A4 (33.80±0.30), the highest pH value was Seaweed from Bontang using direct sun-drying A3 (8.58 ± 0.04), the highest gel strength was seaweed from UMS in Salakan Island using direct sundrying A2 (433 ± 0.01 g/cm2). Based on ice cream test results, the hardness of the control showed a significant difference (p<0.05) from the treatment. The highest hardness was seaweed from community of Salakan Island using direct sun-drying A1 (372.04 ± 2.09 g/cm2), the highest overrun was seaweed from UMS in Salakan Island using sauna method B2 (74,44 ± 0,69%), the melting speed of seaweed from UMS in Salakan Island using sauna method B2 treatment showed a significant difference (p<0.05) from other treatments, the highest melting rate was seaweed from Sangatta using direct sun-drying A4 (1.22 ± 0.02 g/min). Kappaphycus alvarezii is a type of seaweed that is widely cultivated in waters of Sabah and East Kalimantan. Carrageenan derived from seaweed in Sabah waters had high fibre and gel strength compared to the carrageenan from Kalimantan waters. Carrageenan derived from seaweed of Salakan Island, which was directly sun-dried, showed the strength of ice cream dough. Carrageenan derived from seaweed which was dried using the direct sun-drying method showed a high melting rate of ice cream