MATHEMATICAL ANALYSIS OF THE EFFECT OF VARIOUS PRE-TREATMENTS AND DRYING TIME ON THE QUALITY OF DEHYDRATED PERSIMMON

MILA FIKRI DESINTAMAYA, Dr. Ir. Nursigit Bintoro, M.Sc.

2019 | Skripsi | S1 TEKNIK PERTANIAN

Kesemek (Diospyros kaki) adalah buah yang dikonsumsi dalam kondisi segar dan juga kering. Kesemek kering merupakan produk dengan harga tinggi karena kandungan nutrisi yang tinggi. Pada penelitian ini, kami menerapkan beberapa pre- treatment yang terdiri atas 4 macam (pendinginan suhu 1 derajat celsius, ethanol, karbondioksida, dan buah control). Buah dikeringkan selama 4 hari menggunakan pengering kabinet pada suhu 35 derajat celsius. Kualitas buah selanjutnya dianalisis secara matematika meliputi, warna, kekerasan buah, kadar air, dan tanin terlarut. Analisis warna dibagi menjadi 2 yaitu, kroma dan hue angle. Setelah 4 hari pengeringan, Hue angle pada semua perlakuan menurun dan pre-tretament memberikan pengaruh tidak nyata terhadap perubahan hue angle. Kroma dari kesemek terdehidrasi dipengarui oleh pre-treatment dan waktu pengeringan. Perlakuan karbondioksida dan 1derajat celsius menghasilkan buah dengan nilai kroma yang tinggi. Interaksi antara pre-tretament dan waktu pengeringan juga berpengaruh pada kekerasan buah, kadar air, dan tanin terlarut. Buah yang diberi pelakuan karbondioksida memiliki kekerasan paling tinggi sebesar 20,23 N, sedangkan perlakuan dengan etanol menghasilkan buah yang lebih lunak dengan kekerasan 9,38 N. Kadar air setelah pengeringan 4 hari pada buah yang diberi perlakuan karbondioksida adalah paling rendah yaitu 41, 51 % daripada buah dengan perlakuan lain. Tanin terlarut yang menyebabkan rasa sepat pada kesmek juga mengalami penurunan setelah pre-treatment pada buah yang diberi perlakuan karbondioksida dan etanol, namun setelah 4 hari pengeringan semua buah memiliki kandungan tanin terlarut yang tidak berbeda nyata, yaitu 283,30- 314,68 mg/100g (dry weight), kecuali buah dengan perlakuan 1erajat celsius, yaitu 890,87 mg/100g (dry weight).

Persimmon (Diospyros kaki) was consumed at fresh and also dried condition. Dried persimmon became expensive and outstanding product due to the high nutrition. In this experiment we applied some pre-treatment on dehydrated persimmon to produce high quality fruit. Fresh persimmon fruits were treated with 4 different pre-treatments (cooling at 1 degree Celsius, ethanol, carbon dioxide and untreated fruit as control). Fruits were dried for 4 days using cabinet dryer at 35 degree Celsius. Quality of dried persimmon were analyzed mathematically, involved color, flesh firmness, moisture content and soluble tannin content. Analysis of color divided into two parameters, chroma and hue angle. After 4 days of drying, hue angle value on all treated fruit decreased and treatments were not significantly affected to hue angle value. Chroma of dehydrated persimmons were affected by pre-treatment and drying time. Carbon dioxide and 1 degree Celsius-treated fruit produced higher value of chroma. Same as chroma value, flesh firmness, moisture content and soluble tannin were also significantly affected by interaction between pre-treatment and drying time. Flesh firmness of CO2-treated fruit was higher than other treated fruit, about 20,23 N and ethanol treatment generated lower firmness, about 9,38 N. Moisture content on dehydrated persimmon decreased after 4 days and carbon dioxide- treated fruit had higher moisture content, about 41,51% than other treated fruit. Soluble tannin that responsible to astringent sense on persimmon also decreased after pre-treatment on carbon dioxide and ethanol treatment, however after 4 days of drying all treated fruit had similar content of soluble tannin about 283,30- 314,68 mg/100g (dry weight), except 1 degree Celsius - treated fruit that had higher content, about 890,87 mg/100g (dry weight).

Kata Kunci : chroma, dehydrated persimmon, flesh firmness, hue angle, moisture content, pre-treatment, soluble tannin