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PENGARUH LAMA BLANSIR DAN SUBSTITUSI TEPUNG UBI JALAR UNGU TERHADAP AKTIVITAS ANTIOKSIDAN, WARNA, WATER ABSORPTION, DAN COOKING LOSS MIE BASAH EFFECTS OF BLANCHING TIME AND SUBSTITUTION OF PURPLE SWEET POTATO FLOUR TO ANTIOXIDANT ACTIVITY, COLOUR, WATER ABSORPTION, AND COOKING LOSS OF BOILED NOODLES (xiii + 126 pages : 12 tables, 22 figures, and 23 appendix) Irene Raharjo1), A. Herry Cahyana 2), Tagor M. Siregar 3)
ABSTRACT Effects of blanching time were investigated to know total anthocyanins, total phenolic, and antioxidant activity of purple sweet potato flour and its effects on the boiled noodles resulted. Boiled noodles were made by substituting purple sweet potatoes that were blanched for 5, 10, and 15 minutes before drying process with three different levels substitution purple sweet potato flour (15%, 20%, and 25%). Blanching time for 15 minutes could inactivate peroxide enzyme and polyphenol oxidase enzyme of purple sweet potato. Drying process could decreased total anthocyanins, total phenolic, and antioxidant activity of purple sweet potato flour because of degradation compound by polyphenol oxidase enzyme. Blanching for 15 minutes had the highest total anthocyanins, total phenolic, and antioxidant activity. Substituting purple sweet potato flour for 25% in boiled noodles resulted the highest total anthocyanins and total phenolic, and moreover its antioxidant activity. However, substitution decreased the water absorption and increased their cooking loss. Furthermore, the substitution improved in colour, flavour, taste, texture, and acceptability of boiled noodles. Keywords : boiled noodles, blanching time, substitution, antioxidant activity, anthocyanins, phenolic, References : 47 (1990-2010)
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KATA PENGANTAR
Puji syukur kepada Tuhan Yesus Kristus atas rahmat dan penyertaanNya sehingga penulisan skripsi dengan judul “Pengaruh Lama Blansir dan Subtitusi Tepung Ubi Jalar Ungu terhadap Aktivitas Antioksidan, Warna, Water Absorption, dan Cooking Loss pada Mie Basah.” Selama proses pelaksanaan skripsi, Penulis mendapatkan banyak bantuan dari berbagai pihak. Oleh karena itu, Penulis ingin menyampaikan rasa terima kasih yang sebesar-besarnya kepada: 1.
Bapak Ir. A. Herry Cahyana, M.Sc, Ph.D selaku pembimbing utama yang banyak memberikan bimbingan dan masukan selama pelaksanaan skripsi.
2.
Bapak Tagor M. Siregar, M.Si selaku co-pembimbing yang banyak membantu dan memberikan bimbingan selama pelaksanaan skripsi.
3.
Ibu Nuri Arum Anugrahati sebagai Ketua Jurusan Teknologi Pangan dan Ibu Julia Ratna Wijaya sebagai Wakil Ketua Jurusan Teknologi Pangan yang banyak membantu pelaksanaan skripsi.
4.
Bapak Supriadi Raharjo, Ibu Helen Kwok, dan Catherine Raharjo selaku orang tua dan saudara yang banyak memberikan dukungan baik secara materi maupun moral selama pelaksanaan dan penulisan skripsi.
5.
Ibu Mery Tambaria Damanik, Ibu Ratna Handayani, Bapak Jeremia Manuel Halim, dan Bapak Adolf Parhusip sebagai kepala laboratorium yang mengizinkan penggunaan laboratorium kepada Penulis.
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6.
Bapak Rudy, Bapak Ade, Bapak Hendra, Bapak Yosafat, Bapak Donny, dan Bapak Fauzi sebagai laboran laboratorium yang banyak membantu peminjaman alat kepada Penulis.
7.
Seluruh dosen, asisten dosen, dan staf Jurusan Teknologi Pangan yang telah membantu pelaksanaan skripsi.
8.
William Halim, Livia Sagita Ruslim, Tracy Benn, dan Jessica Tania Hosen sebagai pendengar setia curahan hati, keluh kesah, pemberi semangat, dukungan, hiburan, dan motivasi selama proses pelaksanaan skripsi.
9.
Adeline, Sari, Mikhael, Andre, Angeline, Zenia, Lina, Teresa, Bernike, dan Clara sebagai teman satu bimbingan dan teman seperjuangan yang banyak memberikan masukan dan ide selama proses pelaksanaan skripsi.
10.
Nanik Wijaya, Sylvia, Evelin Natalia Kusno, Natalia Devina, Meliana Wijaya, dan Irene Velecia yang merupakan teman berbagi dan pemberi motivasi selama pelaksanaan skripsi. Pelaksanaan skripsi memberikan pengalaman dan pelajaran yang sangat
berharga bagi penulis. Penulis berusaha untuk melaksanakan skripsi dengan sebaik mungkin, namun Penulis menyadari adanya ketidaksempurnaan dalam penyusunan skripsi. Oleh karena itu, Penulis menerima masukan dan saran yang membangun guna memperbaiki kinerja Penulis. Semoga penulisan skripsi dapat bermanfaat bagi pihak yang membutuhkan.
Jakarta, Februari 2011
Penulis
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DAFTAR ISI Halaman PERNYATAAN KEASLIAN KARYA SKRIPSI ............................................... i PERSETUJUAN DOSEN PEMBIMBING SKRIPSI ........................................ ii PERSETUJUAN TIM PENGUJI SKRIPSI.......................................................iii ABSTRACT .......................................................................................................... iv KATA PENGANTAR ............................................................................................v DAFTAR ISI ........................................................................................................ vii DAFTAR TABEL ................................................................................................ xi DAFTAR GAMBAR ........................................................................................... xii DAFTAR LAMPIRAN ...................................................................................... xiii
BAB I
PENDAHULUAN 1.1 Latar Belakang .....................................................................................1 1.2 Rumusan Masalah ................................................................................3 1.3 Tujuan ..................................................................................................3 1.3.1 Tujuan Umum ............................................................................3 1.3.2 Tujuan Khusus ...........................................................................3
BAB II TINJAUAN PUSTAKA 2.1 Ubi Jalar Ungu .....................................................................................5 2.2 Antosianin ............................................................................................7 2.3 Antioksidan ........................................................................................10 2.3.1 Total Antosianin ......................................................................11 2.3.2 Total Fenolik ............................................................................12 2.3.3 Aktivitas Antioksidan ..............................................................12 2.4 Tepung Ubi Jalar Ungu ......................................................................12 2.5 Mie .....................................................................................................13 2.5.1 Jenis Mie ..................................................................................14 2.5.1.1 Mie Mentah .................................................................14 2.5.1.2 Mie Basah ....................................................................14
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Halaman 2.5.1.3 Mie Kering ..................................................................14 2.5.2 Bahan Baku Pembuatan Mie ....................................................15 2.5.2.1 Tepung Terigu .............................................................15 2.5.2.2 Air ................................................................................16 2.5.2.3 Garam ..........................................................................16 2.5.3 Cara Pembuatan Mie ................................................................16 2.6 Blansir ...............................................................................................17
BAB III METODE PENELITIAN 3.1 Alat dan Bahan ...................................................................................19 3.2 Prosedur Penelitian ............................................................................19 3.2.1 Penelitian Pendahuluan ............................................................19 3.2.2 Penelitian Utama ......................................................................21 3.3 Analisis ..............................................................................................22 3.3.1 Analisis Total Antosianin ........................................................22 3.3.2 Analisis Total Fenolik ..............................................................23 3.3.3 Analisis Aktivitas Antioksidan dengan DPPH ........................24 3.3.4 Uji Enzim Peroksidase .............................................................24 3.3.5 Warna .......................................................................................25 3.3.6 Kadar Air .................................................................................25 3.3.7 Water Absorption .....................................................................26 3.3.8 Cooking Loss............................................................................26 3.3.9 Sensori .....................................................................................27 3.3.9.1 Uji Skoring ..................................................................27 3.3.9.2 Uji Hedonik .................................................................27 3.4 Rancangan Percobaan ........................................................................27 3.4.1 Rancangan Percobaan Penelitian Pendahuluan .......................28 3.4.2 Rancangan Percobaan Penelitian Utama .................................29
BAB IV HASIL DAN PEMBAHASAN 4.1 Ubi Jalar Ungu .................................................................................31
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Halaman 4.1.1 Total Antosianin ......................................................................32 4.1.2 Total Fenolik ...........................................................................34 4.1.3 Aktivitas Antioksidan .............................................................35 4.1.4 Uji Enzim Peroksidase .............................................................37 4.2 Tepung Ubi Jalar Ungu .....................................................................37 4.2.1 Rendemen Tepung Ubi Jalar Ungu .........................................39 4.2.2 Total Antosianin ......................................................................40 4.2.3 Total Fenolik ...........................................................................41 4.2.4 Aktivitas Antioksidan .............................................................43 4.3 Mie Basah .........................................................................................44 4.3.1 Total Antosianin ......................................................................45 4.3.2 Total Fenolik ...........................................................................47 4.3.3 Aktivitas Antioksidan .............................................................48 4.3.3.1 Korelasi antara IC50 dengan Total Antosianin dan Total Fenolik ........................................................50 4.3.4 Warna ......................................................................................51 4.3.5 Kadar Air .................................................................................54 4.3.6 Water Absorption ....................................................................55 4.3.7 Cooking Loss ...........................................................................57 4.3.8 Sensori .....................................................................................59 4.3.8.1 Uji Skoring ..................................................................59 4.3.8.1.1 Warna............................................................59 4.3.8.1.2 Aroma ...........................................................61 4.3.8.1.3 Rasa ..............................................................62 4.3.8.1.4 Tekstur ..........................................................63 4.3.8.2 Uji Hedonik ................................................................64
BAB V KESIMPULAN DAN SARAN 5.1 Kesimpulan ........................................................................................66 5.2 Saran ..................................................................................................67
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Halaman DAFTAR PUSTAKA ...........................................................................................68
LAMPIRAN ..........................................................................................................72
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DAFTAR TABEL Halaman Tabel 2.1 Komposisi kimia ubi jalar ........................................................................5 Tabel 2.2 Komposisi kimia tepung ubi jalar ungu .................................................13 Tabel 2.3 Komposisi gizi mie basah dan mie kering per 100 gram bahan ............15 Tabel 3.1 Formulasi mie basah ..............................................................................21 Tabel 4.1 Hasil analisis total antosianin pada ubi jalar ungu .................................33 Tabel 4.2 Hasil analisis total fenolik pada ubi jalar ungu ......................................34 Tabel 4.3 Hasil analisis aktivitas antioksidan pada ubi jalar ungu .......................36 Tabel 4.4 Hasil uji enzim peroksidase pada ubi jalar ungu....................................37 Tabel 4.5 Rendemen tepung ubi jalar ungu ...........................................................40 Tabel 4.6 Hasil analisis total antosianin pada tepung ubi jalar ungu ....................40 Tabel 4.7 Hasil analisis total fenolik pada tepung ubi jalar ungu ..........................41 Tabel 4.8 Hasil analisis aktivitas antioksidan pada tepung ubi jalar ungu ............43
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DAFTAR GAMBAR Halaman Gambar 2.1 Ubi jalar ungu .....................................................................................6 Gambar 2.2 Struktur antosianin .............................................................................7 Gambar 2.3 Jenis antosianidin ...............................................................................7 Gambar 3.1 Prosedur pembuatan tepung ubi jalar ungu.......................................20 Gambar 3.2 Prosedur pembuatan mie basah.........................................................22 Gambar 4.1 Ubi jalar ungu Thailand “Bona Vista” ..............................................31 Gambar 4.2 Tepung ubi jalar ungu .......................................................................38 Gambar 4.3 Total antosianin mie basah pada berbagai komposisi tepung ubi jalar ungu ....................................................................................45 Gambar 4.4 Total fenolik mie basah pada berbagai komposisi tepung ubi jalar ungu ...................................................................................47 Gambar 4.5 Aktivitas antioksidan mie basah pada berbagai komposisi tepung ubi jalar ungu ...................................................................................49 Gambar 4.6 Korelasi antara IC50 dengan total antosianin ....................................50 Gambar 4.7 Korelasi antara IC50 dengan total fenolik.........................................50 Gambar 4.8 Intensitas kecerahan pada mie basah ................................................52 Gambar 4.9 Mie basah dengan berbagai subtitusi tepung ubi jalar ungu .............53 Gambar 4.10 Kadar air mie basah pada berbagai komposisi tepung ubi jalar ungu ...................................................................................54 Gambar 4.11Water absorption pada mie basah .....................................................55 Gambar 4.12 Cooking loss pada mie basah ............................................................58 Gambar 4.13 Penilaian warna ungu mie basah pada berbagai komposisi tepung ubi jalar ungu ...................................................................................60 Gambar 4.14 Penilaian aroma manis pada mie basah ............................................61 Gambar 4.15 Penilaian rasa manis pada mie basah ...............................................62 Gambar 4.16 Penilaian kekenyalan pada mie basah ..............................................63 Gambar 4.17 Penilaian tingkat kesukaan mie basah pada berbagai komposisi tepung ubi jalar ungu ......................................................................65
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DAFTAR LAMPIRAN Halaman Lampiran 1. Hasil Analisis Total Antosianin pada Ubi Jalar Ungu ......................73 Lampiran 2. Kurva Standar Asam Galat pada Ubi Jalar Ungu .............................75 Lampiran 3. Hasil Analisis Total Fenolik pada Ubi Jalar Ungu ..........................76 Lampiran 4. Analisis Aktivitas Antioksidan pada Ubi Jalar Ungu .......................78 Lampiran 5. Rendemen Tepung Ubi Jalar Ungu ..................................................81 Lampiran 6. Hasil Analisis Total Antosianin pada Tepung Ubi Jalar Ungu ........82 Lampiran 7. Hasil Analisis Total Fenolik pada Tepung Ubi Jalar Ungu .............83 Lampiran 8. Hasil Analisis Aktivitas Antioksidan pada Tepung Ubi Jalar Ungu 84 Lampiran 9. Hasil Analisis Total Antosianin pada Mie Basah ............................88 Lampiran 10.Kurva Standar Asam Galat pada Penelitian Utama .........................90 Lampiran 11. Hasil Analisis Total Fenolik pada Mie Basah ................................91 Lampiran 12. Hasil Analisis Aktivitas Antioksidan pada Mie Basah ....................93 Lampiran 13. Hasil Analisis Kromameter ...........................................................103 Lampiran 14. Hasil Analisis Kadar Air................................................................107 Lampiran 15. Hasil Analisis Water Absorption ...................................................109 Lampiran 16. Hasil Analisis Cooking Loss ..........................................................111 Lampiran 17. Lembar Kuisioner Uji Skoring ......................................................113 Lampiran 18. Hasil Uji Skoring terhadap Warna Ungu .......................................114 Lampiran 19. Hasil Uji Skoring terhadap Aroma Manis .....................................117 Lampiran 20. Hasil Uji Skoring terhadap Rasa Manis ........................................119 Lampiran 21. Hasil Uji Skoring terhadap Kekenyalan ........................................121 Lampiran 22. Lembar Kuisioner Uji Hedonik .....................................................123 Lampiran 23. Hasil Uji Hedonik ..........................................................................124
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