JURNAL TEKNIK KIMIA VOKASIONAL (JIMSI)

EFEKTIVITAS EKSTRAK DAUN KARAMUNTING (Rhodomyrtus tomentosa) SEBAGAI BAHAN PENGAWET ALAMI TOMAT (Solanum lycopersicum L)

Elis Diana Ulfa — 2025-04-21

Tomatoes are classified as a horticultural commodity that is very perishable which can cause shrinkage in quantity and quality. After harvesting tomatoes, there is still a metabolic process so that there is the potential for damage. Efforts are needed to maintain the quality of tomatoes by preserving them using natural preservatives from natural ingredients such as karamunting leaf extract. Positive karamunting leaves contain alkaloid compounds, flavonoids, saponins, tannins, triterpenoids, steroids and carbohydrates with potential antioxidant and antimicrobial compounds. This study aims to determine the effectiveness of karamunting leaf extract as a natural preservative of tomatoes. The tomato preservation process begins by washing them thoroughly and draining them. Then the tomatoes are dipped in a solution of karamunting leaf extract with concentration variations of 0%, 2%, 4%, 6%, and 8% in 100 mL of solution for 5 seconds and left for several days at room temperature until optimal storage. The results of the study showed that karamunting leaf extract as a natural preservative was effective for preserving tomatoes. The best tomato preservation was obtained in the use of 8% karamunting leaf extract with tomato durability for 19 days, weight loss of 3.74%, and vitamin C content of 29.883 mg.

Pengaruh Konsentrasi Aktivator Asam Klorida (HCl) pada Aktivasi Karbon Aktif dari Ampas Teh

Sesy Alvira Dwi Saskia — 2025-04-21

Tea dreg is a waste that is often wasted, the utilization of tea waste is still very limited and in a small scope. The field of animal husbandry uses tea as an addition in making compost, besides being used as organic fertilizer, tea dregs can also be used as activated carbon as an adsorbent. In making activated carbon, the content of tea pulp that is taken into account is holocellulose, which is 60.81%. Tea pulp consists of cellulose of 29.42%, and lignin of 36.94%. In making activated carbon, the carbonization process needs to be done. The purpose of this study was to determine the effect of hydrochloric acid (HCl) concentration on the activation of activated carbon from tea dregs on the quality characteristics of activated carbon produced referring to SNI standard No. 06-3730-1995. Tea dregs were carbonized using a furnace at 400 ℃ for 20 minutes with varying concentrations of HCl 0.5 M; 1 M; 1.5 M; 2 M and 2.5 M for 48 hours. The best results were found at 1 M HCl concentration with an iodine absorption value of 896.287 mg/g, moisture content of 8.26%, ash content of 2.91%, volatile matter of 24.33% and fixed carbon of 64.5%.

PENGARUH KECEPATAN SHAKER DALAM ADSORPSI ZAT WARNA (METHYL ORANGE) MENGGUNAKAN CANGKANG TELUR AYAM

Nurul Anggraeni Basri — 2025-04-21

The batik industry in Samarinda has been continuously developing from year to year. According to 2024 data, the batik industry generates wastewater amounting to 2,678,400 liters annually. This wastewater contains hazardous compounds, one of which is Methyl Orange, an aromatic azo compound characterized by a double bond (-N=N) and its carcinogenic properties. Therefore, it is necessary to treat the wastewater to eliminate the azo dye completely. One approach that can be applied is adsorption, due to its simplicity and widespread use in treating various types of pollutants. This study aims to investigate the effect of the presence or absence of a shaker on the effectiveness of eggshells as an adsorbent in reducing the dye concentration. The methods used in this research include adsorbent preparation, the adsorption process, and UV-Vis spectrophotometric analysis. Adsorption was carried out with variations in shaker speed at 120, 160, 200, 240, and 280 RPM. The results showed the highest adsorption efficiency of 57.80% at an adsorbent mass of 11 grams, pH 1, for 60 minutes, with a shaker speed of 120 RPM.

PENGARUH ASAM SEBAGAI MORDAN TERHADAP HASIL PEWARNAAN PADA KAIN KATUN MENGGUNAKAN ZAT WARNA DARI EKSTRAK KUNYIT

Juwita Lutfiah Wardani — 2025-04-21

The increasing demand for natural dyes as an alternative to synthetic dyes, which can pollute the environment, has gained significant attention. Turmeric (Curcuma domestica Val) is commonly used as a natural dye source due to its curcuminoid content, which produces a yellow color. However, natural dyes tend to be less stable and more prone to fading, necessitating the use of a mordant as a binding agent to improve color fastness on fabric fibers. This study aims to examine the effect of using acidic mordants, specifically alum, ferrous sulfate (tunjung), and citric acid, on the dyeing results of cotton fabric using turmeric dye. The methodology involved a pre-mordanting process using alum, followed by a combination of post-mordanting treatments with alum, ferrous sulfate, and citric acid. Cotton fabric samples treated with alum and citric acid produced a bright yellow color, while samples treated with ferrous sulfate resulted in a brownish-yellow hue. The parameters tested included color depth (R%), color fastness to soap washing, and color fastness to staining on white fabric. The results indicated that cotton fabric treated with pre-mordanting using alum and turmeric dye achieved a color fastness rating of 4 (good) for soap washing, with a color depth value of 2.98. The combination of pre-mordanting and post-mordanting using alum as a mordant produced the highest color depth value of 7.03, along with good color fastness performance.

PENGARUH KONSENTRASI ASAM ASETAT TERHADAP KARAKTERISTIK GELATIN DARI KULIT KAKI AYAM BROILER

mutliah muyasaroh — 2025-04-21

Chicken feet skin is a part of chicken feet that consists of collagen, fat, and connective tissue. Chicken feet skin has a potential of about 156,933 tons/year. This study was conducted to determine the effect of acetic acid concentration on the characteristics of gelatin from broiler leg skin. The first process was the deproteinization process using NaOH solution with a concentration of 0.15% and a soaking time of 2 x 40 minutes; the second process was the demineralization process using CH3COOH solution with a concentration variation of 0.5%, 1%, 1.5%, 2%, and 2.5% and a soaking time of 4 hours; the third process was the hydrolysis process with water using a waterbath at 60°C for 5 hours. The results showed that the best acetic acid concentration variation was obtained at 2.5% acetic acid concentration with a yield of 6.12%, 4.09% moisture content and 1.59% ash content and has met the SNI 06-3735 standard in 1995.