The effect of temperature and time of extraction on the quality of Semi Refined Carrageenan (SRC)

Abstract

Euchema cottonii is a good source of kappa-carrageenan and can be found cultivated in the Indonesia coastal areas in which one of them is in Banten Province. Carrageenans have many applications and are utilized in human food and pet-food industry. Carrageenans are also utilized in non-food industry such as pharmaceuticals, cosmetics, printing and textile formulations. Hence, the present study features on the cooking process cooking time and cooking temperature. The effects of these parameters on carrageenan quality such as gel viscosity and gel strength were studied. The process of extraction of carrageenan was conducted with variations temperature: 60, 70, and 80 °C and the variation of time: 1, 2, and 3 hours. Alkaline substance used was KOH with 8% concentration and the ratio of solvent to dry seaweed 8:1. From the present investigation, it was observed that SRC extraction reached the best condition at temperature 70 °C for 2 hours with the value of yield 30.20%, 5.90% moisture content, 18.34% ash content, sulfate content of 6.94%, viscosity of 190 cP, and the gel strength 714.45 g / cm2. The treatment of temperature and extraction time significantly affected the quality of the SRC yield parameter, viscosity and gel strength.

Impact of elevated temperature on the physiological and biochemical responses of Kappaphycus alvarezii (Rhodophyta)

“…Temperature can affect the yield and quality of carrageenan, as observed in K . alvarezii (formerly known as Eucheuma cottonii ) [ 6 ]. Our present study, which showed that seaweeds incubated at 32, 36 and 40°C produced significantly lower carrageenan yield compared to seaweeds incubated at 28°C, corroborate with previous studies [ 53 – 55 ], which reported that incubation of seaweeds beyond conducive temperature lowers their gel strength and gel viscosity.…”

“…Carrageenan is a family of gel-forming, viscosifying polysaccharides [ 5 ] consisting of sulfated galactans with a backbone of alternating 4-linked α-D- galactopyranosyl and 3-linked β-D-galactopyranosyl monomers. In an effort to improve the economic value, seaweeds are made into Semi Refined Carrageenan (SRC), via a process to meet the quality standards of food (food grade) [ 6 ]. The price of seaweed could reach US$ 3.50 to US$ 5.50 per kg once processed into SRC and the value of seaweed carrageenan increases to US$ 9 per kg after Refined Carrageenan (RC) production [ 7 ].…”

KARAKTERISTIK KARAGENAN SEMI-MURNI DARI RUMPUT LAUT Kappaphycus striatum DAN Kappaphycus alvarezii

“…Persentase rendemen tertinggi masing-masing sampel didapatkan pada konsentrasi 6% dengan waktu ekstraksi 60. Menurut Heriyanto et al (2018) penggunaan suhu ekstraksi yang tinggi dengan waktu yang lama dapat meningkatkan rendemen karagenan. Semakin lama waktu ekstraksi menyebabkan pengikatan gugus sulfat pada rantai keenam semakin lama yang mengakibatkan pembentukan 3,6-anhidrogalaktosa semakin banyak, meskipun pada hasil penelitian ini lama waktu ekstraksi dan konsentrasi KOH tidak memberikan pengaruh signifikan pada rendemen SRC yang dihasilkan.…”

“…Semakin lama waktu ekstraksi semakin rendah viskositas yang dihasilkan. Heriyanto et al (2018) pada penelitiannya menemukan bahwa karagenan semi-murni yang diekstraksi dengan waktu ekstraksi yang lebih lama mengalami penurunan nilai viskositas yaitu 337,5 cP pada lama ekstraksi 1 jam dan 70 cP pada lama ekstraksi 3 jam. Kondisi tersebut disebabkan oleh penurunan jumlah gugus sulfat pada karagenan yang dihasilkan serta tingginya pembentukan 3,6-anhidrogalaktosa dapat menurunkan viskositas larutan karagenan.…”

“…Faktor-faktor seperti lama waktu ekstraksi, rasio air pengekstrak, konsentrasi alkali, jenis alkali dan suhu yang digunakan dilaporkan memberikan pengaruh terhadap karakteristik karagenan. Heriyanto et al (2018) melakukan ekstraksi karagenan semi-murni dari rumput laut K. alvarezii dengan karakteristik terbaik pada kondisi ekstraksi suhu 70°C selama 2 jam dengan rendemen sebesar 30,2%, viskositas 190 cP, kekuatan gel 714,45 g/cm 2 . Sormin et al (2018) juga melakukan ekstraksi karagenan semi-murni dengan konsentrasi KOH 0,5% pada suhu 75°C selama 30 menit menggunakan bahan baku rumput laut yang direndam dengan larutan CaCO 2 2% selama satu malam sebelum dilakukan proses ekstraksi.…”