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Karakteristik Fisiko-Kimia Karagenan Rumput Laut Merah Eucheuma Spinosum Dari Perairan Nusa Penida, Sumenep, Dan Takalar
No full textKaragenan hasil ekstrak rumput laut merah (Rhodopyceae) tersusun dari senyawa polisakarida berantai linier, galaktan sulfat, dan larut di dalam air. Berdasarkan kandungan sulfatnya, karagenan terdiri dari fraksi kapa, iota, dan lamda, yang dihasilkan dari spesies yang berbeda. Spesies rumput laut merah penghasil karagenan di Indoensia adalah Eucheuma cottonii (Kappaphycus alvarezii) dan Eucheuma spinosum (denticulatum).
Karagenan adalah salah satu ingredien pangan yang berfungsi sebagai penstabil, pengental, dan pembentuk gel. Sentra budidaya E. spinosum di Indonesia berada di perairan Nusa Penida, Sumenep, dan Takalar. Diperkirakan lokasi budidaya rumput laut berpengaruh terhadap kualitas karagenan yang dihasilkan.
Penelitian ini bertujuan untuk 1) menganalisis perbedaan komposisi kimia rumput laut E. spinosum, 2) menganalisis perbedaan karakteristik fisik dan kimia karagenan, 3) menganalisis perbedaan profil viskositas karagenan pada suhu 80–20C tanpa dan dengan kation K+ dan Ca2+, dan 4) mengkaji profil reologi larutan karagenan pada suhu 60, 65, dan 70C dari rumput E.spinosum yang berasal dari perairan Nusa Penida, Sumenep dan Takalar..
Rumput laut E. spinosum yang dianalisis adalah komposisi proksimat (kadar air, abu, lemak, protein, karbohidrat), dan serat kasar, sedangkan terhadap karagenan meliputi rendemen dan kadar air. Selanjutnya dilakukan analisis karakteristik kimia karagenan yang meliputi kadar abu, abu tidak larut asam, sulfat, kadar mineral, dan logam berat, identifikasi senyawa karagenan melalui profil spectrum senyawa karagenan menggunakan spektrofotometer Fourier Transform Infrared (FTIR), dan bobot molekul dengan GPC-HPLC. Analisis karakteristik fisik terdiri atas kekuatan gel, derajat putih, viskositas, profil viskositas dengan penambahan kation K+ dan Ca2+, serta analisis profil reologi larutan karagenan pada suhu 60, 65, dan 70C dari rumput laut E.spinosum yang berasal dari periaran Nusa Penida, Sumenep , dan Takalar.
Kadar air rumput laut E. spinosum kering dari ketiga perairan (Nusa Penida, Takalar, dan Sumenep) berkisar antara 19–20% (bb). Komposisi kimia rumput laut dari ketiga perairan adalah kadar abu 23.35–24.30% (bk), lemak 0.012–0.076% (bk), protein 6.30–7.30% (bk), karbohidrat 69.07 – 69.66 % (bk), dan serat total 15.14–19.27% (bk). Eucheuma spinosum yang berasal dari ketiga perairan memiliki kadar air, lemak, protein, lemak, dan karbohidrat yang tidak berbeda, hanya kadar serat kasar yang berbeda nyata.
Ekstrak E. spinosum dari ketiga perairan menghasilkan karagenan dengan rendemen 25–37% dan kadar air 9–11% bb. Rendemen karagenan tertinggi berasal dari perairan Takalar diikuti karagenan dari Sumenep dan Nusa Penida. Karagenan secara kimia memiliki kadar abu 28.26–29.57% (bk), kadar sulfat 30.74-32.27% (bk), dan kadar abu tidak larut asam 0.27– 0.33% (bk). Kadar mineral (kalsium, kalium, magnesium, dan natrium) dari perairan Nusa Penida, Sumenep, dan Takalar menunjukkan perbedaan. Rasio kalsium terhadap kalium karagenan Nusa Penida, Sumenep, dan Takalar berturut-turut 2.62, 2.92, dan 3.52. Hasil analisis terdeteksi kandungan logam berat menunjukkan bahwa karagenan ini tidak mengandung logam berat (Pb, Hg, Cd dan As).
Spektrum FTIR untuk ketiga jenis karagenan menunjukkan adanya gugus fungsi galaktosa-2-sulfat (G2S), anhidrogalaktosa-4-sulfat (DA4S), serta galaktosa, ikatan glikosidik, anhidro-galaktosa, dan ester sulfat pada bilangan gelombang yang hampir sama. Terdapatnya gugus G2S dan DA4S pada ketiga karagenan pada bilangan gelombang 806 dan 852 cm-1 menunjukkan bahwa karagenan E. spinosum dari ketiga perairan adalah tipe iota-karagenan. Analisis bobot molekul karagenan ketiga perairan menggunakan GPC-HPLC mengkonfirmasi bahwa ketiga karagenan adalah iota-karagenan dan mempunyai bobot molekul berkisar antara 8.40 – 9.01 x 105 Dalton.
Kekuatan gel karagenan tertinggi berasal dari perairan Takalar, diikuti Sumenep dan Nusa Penida. Nilai derajat putih tertinggi juga berasal dari karagenan Takalar. Profil viskositas ketiga karagenan pada suhu 80C di awal pengukuran berbeda, viskositas karagenan tertinggi berasal dari perairan Takalar, diikuti Sumenep dan Nusa Penida, dan ketika suhu diturunkan ketiga karagenan menghasilkan peningkatan nilai viskositas. Kekuatan gel dan profil viskositas berbanding lurus dengan rasio kalsium terhadap kalium. Penambahan ion K+ terlihat sangat berpengaruh lebih nyata pada viskositas karagenan Nusa Penida yang memiliki rasio kalsium terhadap kalium paling rendah, sedangkan penambahan ion Ca2+ berpengaruh nyata pada karagenan Takalar yang memilii rasio kalsium terhadap kalium paling tinggi. Kandungan kalsium dan kalium indigenus berpengaruh terhadap viskositas dengan penambahan ion eksogenus.
Profil reologi larutan karagenan Nusa Penida, Sumenep, dan Takalar pada suhu 70C memiliki pola ang serupa yaitu larutannya mudah dialirkan (Newtonian). Reologi karagenan Nusa Penidam Sumenep pada suhu 65C, memiliki profil yang serupa masih Newtonian, kecuali Takalar dan pada suhu 60C, profil reologi Sumenep dan Takalar serupa yaitu larutannya sukar untuk dialirkan (Non Newtonian) sedangkan Nusa Penida masih Newtonian
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Profil asam lemak abon ikan dengan penambahan buah nangka selama penyimpanan: Fatty acid profile of fish floss with the addition of jackfruits during storage
No full textAbon ikan merupakan produk yang terbuat dari daging ikan yang diberi bumbu sebagai penambah citarasa. Penambahan buah nangka pada abon diharapkan dapat menambah citarasa dan aroma, meningkatkan nilai gizi dan menambah variasi produk abon ikan. Penelitian ini bertujuan untuk menentukan karakteristik mutu abon ikan patin dengan penambahan nangka selama penyimpanan. Rasio antara ikan patin dan nangka adalah 2:1 (b/b). Parameter uji yang dilakukan antara lain kadar lemak, asam lemak bebas, bilangan peroksida dan asam lemak total. Penelitian menggunakan rancangan acak lengkap (RAL) dengan perlakuan lama penyimpanan berbeda, yaitu 15, 30 dan 45 hari dengan 3 kali ulangan. Lama penyimpanan berbeda menunjukkan kadar lemak 23,39-23,45%, asam lemak bebas 0,34-0,38% dan bilangan peroksida pada abon ikan nangka meningkat pada penyimpanan 45 hari dengan nilai 5,74-8,26 meq/Kg. Asam lemak total pada abon nangka selama penyimpanan mengalami peningkatan berkisar 80,58-88,48%. Kandungan asam lemak tertinggi, yaitu pada asam oleat 33,36-36,57%, sedangkan yang paling rendah, yaitu asam pentadekanoat 0,03-0,04% dan asam arakidonat 0,03-0,04%.Fish floss is a product made from seasoned fish meat to add flavor. The addition of jackfruit to fish floss is expected to add flavor and aroma, increase the nutritional value, and increase the variety of fish floss products. This study aimed to determine the quality characteristics of shredded catfish and jackfruit during storage. The catfish to jackfruit ratio was 2:1 (w/w). The test parameters included the fat content, free fatty acids, peroxide value, and total fatty acid content. The study used a completely randomized design (CRD) with different storage length treatments, namely 15, 30, and 45 days, with three replications. Different storage times showed that the fat content is 23.39–23.45%, the free fatty acids are 0.34–0.38%, and the peroxide value in jackfruit shredded fish increased after 45 days of storage, with a value of 5.74–8.26 meq/kg. The total fatty acid content in jackfruit shreds during storage increased by approximately 80.58–88.48%. The highest fatty acid content was oleic acid (33.36–36.57%), while the lowest was pentadecanoic acid (0.03–0.04%) and arachidonic acid (0.03–0.04%)
Characteristic of gelatin bone tilapia (Oreochromis nilaticus) extracted with acid and base
Get PDFThis study was aimed to determine chemical and physical characteristics of extracted tilapia fish bone gelatin using acid (HCl) and alkaline (NaOH) solutions. The research method was used comparative experimental with Paired t-test consisting of 2 treatments, namely 4% HCl and 4% NaOH with 3 replications. Analysis parameters was consisted of yield, gel strength, viscosity, pH, moisture content, and ash. Characteristics of gelatin extracted using acid solution was resulted in yield, gel strength and viscosity was 4.40, 182.65 g/bloom. and 9.90 cP. Characteristic of gelatin extracted with acid has moisture, ash and pH levels of 5.85%, 2.35%, and 4.25. Gelatin extracted with bases was produced physical characteristics of yield, gel strength, and viscosity of 4.67%, 150.41 g/bloom and 6.03 cP and chemical characteristics (moisture, ash, and pH) were 5.77%, 3.37%, and 10.24. The extraction process using acids and bases resulted in tilapia fish bone gelatin with significantly different characteristics on gel strength, viscosity, pH, and ash except yield and moisture content. Gelatin was produced from tilapia fish bones using acids has gel strength, pH, ash, and moisture content in accordance with SNI standards except for viscosity, while gelatin uses bases had gel strength, viscosity and moisture content, except for pH and ash.Keywords: characteristic physico-chemical; gel strength; pH; viscosity; yiel
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Karakteristik dan Profil Asam Lemak Kombinasi Minyak Ikan Patin dan Minyak Hati Ikan Hiu: Characteristics and Fatty Acid Profile of Catfish and Shark Liver Oil Mixture
No full textMinyak ikan patin mengandung kadar asam lemak omega-9, tetapi rendah asam lemak omega 3 Minyak hati ikan hiu memiliki kandungan asam lemak omega 3 relatif tinggi. Penelitian ini bertujuan untuk menentukan karakteristik dan sifat kimia minyak ikan patin dan profil asam lemak kombinasi minyak ikan patin dengan hati kan hiu. Metode penelitian eksperimen dengan melakukan ekstraksi lemak perut ikan patin secara dry rendering dihasilkan minyak kasar dan dimurnikan. Minyak ikan patin murni dilakukan pencampuran dengan minyak hati ikan hiu. dengan perbandingan 1:1, 2:1 dan 2:1. Parameter analisis terdiri atas karakteristik kimia (bilangan asam lemak bebas (ALB),bilangan asam, peroksida, iod, p-anisidin, penyabunan, total oksida/totox), dan profil asam lemak. Hasil penelitian menunjukkan bahwa kombinasi minyak patin dan hati ikan hiu dihasilkan karakteristik kimia terdiri atas asam lemak bebas sebesar 1,59-2,19%, bilangan asam 2,86-3,00 mg KOH/g, peroksida 15,50-18,32 meq/kg, iod 63,46-84,42 gI2/100g), p-anisidin 21,53-24,16, penyabunan 142,21-162,28 mg KOH/g dan TOTOX 53,33-69,43. Hasil analisis komposisi asam lemak jenuh (saturated fatty acid/SAFA) dihasilkan asam palmitat tertinggi, asam lemak tak jenuh tunggal (mono unsaturated fatty acid/MUFA) asam oleat, dan asam lemak tak jenuh ganda (polyunsaturated fatty acid/PUFA) asam linoleat. Hasil analisis karakteristik kimia kombinasi minyak ikan patin dan hati ikan hiu sesuai dengan standar IFOMA. Kombinasi minyak hati ikan hiu dan ikan patin dengan perbandingan (2:1) dihasilkan kandungan omega 3 dan omega 6 sebesar 2,59 % dan 29,75%.Catfish oil is rich in omega-9 fatty acids but low in omega-3 fatty acids. Meanwhile, shark liver oil has a relatively high omega 3 fatty acids content. This study was aimed to determine the characteristics and chemical properties of catfish oil and the fatty acid profile of the catfish oil and shark liver mixture. TBbelly fat of catfish was extracted by dry rendering resulting crude and purified oil. The refined catfish oil ismixed with shark liver oil with a ratio of 1: 1, 2: 1 and 2: 1. The analysis parameters consisted of chemical characteristics (free fatty acid, acid value, peroxide, iodine, p-anisidine, saponification, total oxidation/TOTOX), and fatty acid profile. The results showed that the combination of catfish oil and shark liver produced free fatty acids ranging from 1.59-2.19%, acid number 2.86-3.00 mg KOH/g peroxide value15.50-18.32 meq/kg, iodine number 63.46- 84.42 gI2/100g), p-anisidin value 21.53-24.16, saponification 142.21-162,28 mg KOH/g, and TOTOX 53.33-69.43. Palmitic acid, oleic acid, and linoleic acid were the most dominant saturated, monounsaturated and polyunsaturated fatty acid, respectively. The chemical properties meet the IFOMA\u27s standards. The combination of shark liver oil and catfish with a ratio (2:1) resulted in the highest content of omega-3 (0.65%) and omega-6 (29.75%)
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Effect of Light Intensity on the Photo-Oxidation Stability of Silver Catfish Oil (Pangasius hypophthalmus)
No full textTujuan penelitian ini untuk mengkaji pengaruh intensitas cahaya terhadap stabilitas foto-oksidasi minyak ikan patin. Minyak ikan patin murni sebanyak 30 ml disimpan dalam botol transparan bertutup selama 14 hari pada kondisi cahaya yang berbeda dan dilakukan penarikan setiap 2 hari. Perlakuan adalah MIP1 (dibungkus alufo), MIP2 (tanpa dibungkus,), MIP3 (5.000 lux), MIP4 (10.000 lux), dan MIP5 (15.000 lux). Perlakuan MP1 dan MP2 dilakukan dalam ruangan terbuka, sedangkan perlakuan MP3, MP4, dan MP5 dilakukan menggunakan kotak cahaya yang dapat dikontrol intensitas cahaya dan suhu. Mutu minyak yang dievaluasi selama penyimpanan adalah bilangan peroksida, bilangan TBA, waktu induksi, dan penilaian sensori terhadap aroma. Hasil penelitian menunjukkan bahwa paparan cahaya mempercepat kenaikan bilangan TBA, tetapi menurunkan waktu induksi dan penilaian sensori secara deksriptif dan hedonik terhadap aroma minyak. Minyak yang disimpan dalam paparan intensitas cahaya 15.000 lux memperlihatkan peningkatan bilangan TBA tertinggi dengan nilai k 0,240 mg malonadehid/kg (r2=0,86) dan waktu induksi terendah selama 0,81 jam. Aroma tengik terkuat dan tingkat kesukaan terendah terdapat pada minyak setelah disimpan selama 14 hari pada paparan intensitas cahaya 15.000 lux dengan skor 2,2 (tengik) dan 1,41 (sangat tidak suka). Di sisi lain, bilangan peroksida kurang sensitif mengindikasikan stabilitas foto-oksidasi minyak ikan patin, dimana peningkatan bilangan peroksida tertinggi ditunjukkan pada paparan intensitas cahaya 10.000 lux dengan nilai k 0,192 meq O2/kg (r2=0,96). The purpose of this research was to study the effect of light intensity on photo-oxidation stability of silver catfish oil. A pure of 30 ml catfish oil was stored in sealed transparent bottles for 14 days under different light conditions and withdrawal every 2 days. The treatments were MIP1 (wrapped with alufo), MIP2 (without wrapped), MIP3 (5,000 lux), MIP4 (10,000 lux), and MIP5 (15,000 lux). The MP1 and MP2 treatments were conducted in an open space, while MP3, MP4, and MP5 treatments were carried out using a lightbox that can be controlled for light intensity and temperature. The oil quality evaluated during storage was PV, TBA value, induction time, and sensory assessment of aroma. The results showed that light exposure accelerated an increase of TBA value, but decreased induction time and sensory descriptively and hedonically for the aroma of the oil. The oil which stored in light exposure of 15,000 lux showed the highest rate increase of TBA values with k value of, 0.240 mg malonaldehyde/kg (r2=0.86) and the lowest induction time of 0.81 hours. The strongest rancid aroma and the lowest hedonic score were found in the oil which stored in the light exposure of 15,000 lux with a score of 2.2 (rancid) and 1.41 (strongly disliked). On the other hand, PV was not sensitive to indicate the photo-oxidation stability of the oil, where the highest increase of the PV was shown in the light exposure of 10,000 lux with k value of 0.192 meq O2/kg (r2=0.96
Identification of bioactive compounds in extract fraction red seaweed (Eucheuma cottonii)
Get PDFSeaweed is a biological resource that is rich in nutrients and bioactive compounds. This study aims to determine qualitatively and quantitatively the bioactive compounds (flavonoids, alkaloids, steroids/terpenoids, saponins and phenols) from extracts and fractions of Eucheuma cottonii. The method used is an experiment by conducting a series of experiments by extracting and fractionating E. cottonii and the data were analyzed descriptively. The treatments used were organic solvents with different polarity levels (methanol, n-hexane, ethyl acetate, and butanol) for extraction and fractionation. Parameter analysis consisted of qualitative phytochemical tests (flavonoids, alkaloids, steroids/terpenoids, saponins and phenols) and quantitatively determined the total content of alkaloids, flavonoids, and saponins. The results of the phytochemical test of methanol extract qualitatively produced alkaloids, flavonoids, steroids/terpenoids, and saponins. The n-hexane fraction contains steroids/terpenoids and saponins. The ethyl acetate fraction contains alkaloids, flavonoids and steroids/terpenoids and the butanol fraction contains alkaloids. The results of quantitative analysis of the n-hexane extract fraction showed that the content of saponins was 0.23%, alkaloids and flavonoids were 0.16% and 0.09% in the ethyl acetate fraction, while the alkaloid content was 0.09% in the butanol fraction.Keywords: fractionation; organic solvent; phytocemical; quantitativ
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