KOVALEN: Jurnal Riset Kimia
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Penurunan Kadar Asam dalam Kopi Robusta (Coffea canephora) dari Desa Rantebua Kabupaten Toraja Utara dengan Teknik Pemanasan: Reduce Acid Levels in Robusta Coffee (Coffea canephora) from Rantebua Village, North Toraja District by Heating Techniques
Get PDFRobusta coffee (Coffea canephora) is the most widely produced coffee in Indonesia. The relatively high acid content causes robusta coffee to be less attractive to both local and international consumers. Acid levels in coffee can be reduced by heating techniques using water as a solvent because it is cheap and easy to obtain and water is also a safe solvent and has no side effects for health. Coffee bean water content was analyzed by heating to constant weight by the oven method, acid content by titration technique, and followed by organoleptic testing. The results of the analysis of water content for dry treatment of 10.02%, wet treatment of 10.35% and on heating for 15, 30, 45, 60, 75, and 90 minutes respectively at 9.99%; 10.34%; 9.70%; 10.40%; 11.65% and 11.36%. The results of the analysis of acid levels for the treatment of dry processing amounted to 3.65%, wet processing amounted to 3.42%, and for heating for 15, 30, 45, 60, 75, and 90 minutes respectively 3.03%; 2.76%; 2.51%; 2.39%; 2,32% and 2,28%. Organoleptic test results showed that the decline in the quality of coffee occurs when heating above 45 minutes. Based on research data it was concluded that the heating method can reduce acid levels in coffee beans with a maximum heating time of 45 minutes to maintain the quality of taste in coffee.
Keywords: Coffea canephora, organoleptic, warming up, titration
Uji Potensi Metabolit Sekunder Ekstrak Kulit Buah Petai (Parkia speciosa Hassk) terhadap Kadar Kreatinin dan Ureum Tikus Secara Spektrofotometri UV-Vis: Potential Test of Secondary Metabolites Extract of Petai Fruit Peel (Parkia speciosa Hassk) on Creatinine and Ureum Levels of Rats by UV-Vis Spectrophotometry
Get PDFThis study aims to determine the effectiveness of bitter beans peels (Parkia speciosa Hassk) extract on creatinine and urea levels, and the effective dose of the exctract on creatinine and urea levels. This research was a laboratory experiment using 25 rats which were divided into five treatment groups, each group consisting of 5 rats. Group 1 (normal control), group 2 (negative control) were given suspension of Na-CMC, groups 3, 4, and 5 respectively given petai rind ethanolic extract doses of 300, 400 and 500 mg/kg. The results showed that petai fruit (Parkia speciosa hassk) peels extract had an effect on creatinine and urea levels of diabetes hypercholesterolemia male rats by an effective dose of 300 mg/kg which has an effect on creatinine levels by an average of 0.38 mg/dL and ureum levels by an average of 12.9 mg/dL.
Keywords: petai fruit peels extract, secondary metabolite, creatinine, ureum, Streptozotoci
PENGARUH RASIO PELARUT TERHADAP EKSTRAKSI DARI KULIT BUAH NAGA MERAH (Hylocereus polyrhizus)
Get PDFThis study aims to determine the effect of the ratio of solvents to extract yield, phenolics total and IC50 values ​​of red dragon fruit peel and also get the optimal solvent ratio to obtain extract yield, phenolics total and the highest or best IC50 values ​​of red dragon fruit peel extracts. The solvent ratio used there are 6 levels of the ratio: 2:1; 3:1; 4:1; 5:1; 6:1 and 7:1 (v/w). The data obtained were analyzed using a Completely Randomized Design that was applied to observations of extract yield, phenolics total and IC50 values, if the treatment had a very significant or significant effect followed by continued Tukey HSD test at 1% or 5% level. The results showed that the solvent ratio very significantly affected the extract yield, phenolics total and IC50 value of red dragon fruit peel extract. The solvent ratio of 4:1 (v/w) produced extract yield, phenolics total and IC50 values the highest or best i.e 26.22%, 71.56 ppm, and 124.62 ppm.
Keywords : IC50, the red dragon fruit skin, solvent ratio, phenolics tota
FORMULASI MINUMAN EMULSI FUNGSIONAL MENGGUNAKAN KAROTEN KAPANG ONCOM MERAH
Get PDFTelah dilakukan penelitian tentang formulasi minuman emulsi fungsional menggunakan karoten kapang oncom merah.Penelitian ini bertujuan untuk mengetahui konsentrasi emulgator Tween 80 dalam memformulasi minuman fungsional dari karoten kapang oncom merah dalam bentuk emulsi yang stabil dan untuk mengetahui konsentrasi karoten yang digunakan untuk memformulasi minuman fungsional karoten kapang oncom merah dalam bentuk emulsi yang stabil.Penelitian dilakukan tiga tahap yaitu tahap isolasi karoten, tahap pembuatan minuman emulsi karoten dan evaluasi karoten.Kestabilan minuman emulsi ditentukan dengan terbentuknya misel yang dilihat menggunakan mikroskop dan perubahan fisik pada minuman emulsi. Hasil penelitian menunjukkan bahwa hingga penggunaan 1000 ppm karoten, minuman emulsi stabil sampai hari ke-15 dan mengalami kerusakan pada hari ke-21.Kata kunci : Kapang Oncom merah, karoten, emulsi, minuman fungsiona
PEMANFAATAN KARBON AKTIF BIJI KELOR (Moringa oleifera) SEBAGAI PENYERAP LOGAM TIMBAL DALAM OLI BEKAS
Get PDFTelah dilakukan penelitian tentang pemanfaatan karbon aktif biji kelor sebagai penyerap logam timbal dalam oli bekas.Penelitian ini bertujuan untuk menentukan kondisi terbaik dalam penurunan konsentrasi timbal (Pb) tertinggi yang terkandung dalam oli bekas. Adsorben yang digunakan adalah karbon biji kelor yang telah diaktivasi dengan asam klorida (HCl) 1 N. Pada penelitian ini menggunakan 2 variasi yaitu variasi berat adsorben dan variasi waktu kontak adsorben terhadap oli bekas. Hasil penelitian menunjukkan bahwa penurunan konsentrasi timbal tertinggi pada 5 ml oli bekas terdapat pada berat adsorben 15 gram, dan waktu kontak 3 jam. Konsentrasi timbal sebelum perlakuan adalah 2,5345 ppm dan konsentrasi sisa timbal yang didapatkan yaitu sebesar 0,3469 ppm dengan persentase penurunan konsentrasi timbal sebesar 86,31 % . Kata kunci: Adsorpsi, karbon aktif biji kelor, timba
EKSTRAKSI DAN KARAKTERISASI KARAGENAN KASAR RUMPUT LAUT Eucheuma cottoni
Get PDFResearch on extraction and characterization of crude carrageenan from seaweed (eucheuma cottoni) has been carried out. The research aims to determine the optimum extraction time and temperature of crude carrageenan extract from seaweed (eucheuma cottoni). Crude Carrageenan was extracted from seaweed (eucheuma cottoni) by dissolving crushed seaweed in 8% KOH with variation of extraction times are 1 hour, 1.5 hours, 2 hours, 2.5 hours and 3 hours, and temperatures are 50, 70, 90, 110 and 130oC. The results were analyzed using a Completely Randomized Design (CRD). The results show that the optimum extraction time in producing the best quality of crude carrageenan is 2 hours at 50oC with percentage is 78.4%, viscosity is 9.155 cP, sulphate content is 3.102% and gel strength is 7 g.
Keywords : eucheuma cottoni seaweed, crude carrageenan, characterizatio
KADAR PROTEIN TERLARUT DAN GULA TOTAL BISKUIT FUNGSIONAL BERAS JAGUNG (Zea mays l) FERMENTASI
Get PDFTelah dilakukan penelitian tentang kadar protein terlarut dan gula total biskuit fugsional beras jagung fermentasi. Penelitian ini bertujuan untuk mengetahui waktu fermentasi yang memiliki kadar protein terlarut dan gula total tertinggi terhadap biskuit fungsional. Variasi waktu fermentasi untuk        menentukan kadar protein terlarut dan gula total biskuit fungsional yaitu (12, 24, 36, 48 dan 60 jam). Diperoleh hasil analisis perlakuan yang terbaik terhadap biskuit fungsional adalah pada waktu      fermentasi selama 60 jam dengan kadar protein terlarut 2,274% dan kadar gula total 15,114%.      Sedangkan hasil analisis untuk uji organoleptik biskuit fungsional yaitu nilai kesukaan rasa tertinggi diperoleh pada waktu fermentasi selama 60 jam yaitu 5,4 (suka).Kata Kunci: beras jagung, fermentasi, biskuit, protein terlarut, gula tota
STABILITAS EKSTRAK WARNA BUNGA ASOKA (Ixora javanica) BERDASARKAN VARIASI pH SELAMA MASA PENYIMPANAN
Get PDFResearch on the potential of Ashoka (Ixora javanica) flower as a natural food and beverage coloring agent in terms of pH stability during the storage period. This study aims to determine the stability of Asoka flower extract on the effect of pH during the storage period. The time used was 10 days and the variation of pH of 2,3,4,5 and 6, respectively. The results show that Asoka flower extract was stable at pH 2 after a 10-day storage period with degradation presentation of 36.21%, while Ashoka flower extract dyes were unstable at pH 6 after a 10-day storage period with degradation percentage is 78.02%. This proves that the different acidic atmosphere influences the stability of Ashoka flower extract.
Keywords : Dyes, stability of Ashoka flowers, degradatio
AKTIVITAS ANTIBAKTERI FRAKSI n-HEKSAN, KLOROFORM, ETIL ASETAT BUNGA KAMBOJA (Plumeria alba) TERHADAP BAKTERI Staphylococcus aureus DAN Salmonella typhi
Get PDFTests on the inhibition extract of n-hexane fraction, extract of chloroform fraction and extract of ethyl acetate fraction of frangipani flower (Plumeria alba) on Staphylococcus aureus and Salmonella typhi has been done. This study aims to determine the activity of frangipani flower extract on the growth of S. aureus and S. typhi bacteria. Frangipani flowers was macerated using methanol solvents. The obtained methanol extract was partitioned with n-hexane, chloroform and ethyl acetate solvents, respectively. The three extracts were tested for antibacterial activity at a concentration of 10% using the diffusion well method. The test results showed that the n-hexane, chloroform and ethyl acetate fractions showed an inhibition zone of 9.77 mm, 20.89 mm and 19.44 against S. aureus whereas S. typhi showed an inhibition zone of 15.86 mm, 27.69 mm and 21.74 mm.
Keywords: Antibacterial, extract of frangipani flower, Staphylococcus aureus, Salmonella typhi
BIOSORBEN KITOSAN CANGKANG KEONG SAWAH TERHADAP PENYERAPAN ZAT WARNA METHYLENE BLUE
Get PDFBiosorbent studies on methylene blue absorption using chitosan from rice conch shell have been carried out. This research was carried out with variations in contact time of 1, 2, 3, 4, 5, and 6 hours with the aim to determine the contact time required to adsorb Methylene Blue dyes by chitosan from rice conch shell with the highest adsorption capacity. The results showed that the contact time required to adsorb Methylene Blue dye by a chitosan from rice conch shell was 6 hours with the highest adsorption capacity of 85.05%.
Keywords: Chitosan, adsorption, Methylene Blu