SUMMARY Enzyme Modified Cheese (EMC) Flavour Generation with Aspergillus niger Lipase and Lactobacillus casei

SUMMARY Enzyme Modified Cheese (EMC) Flavour Generation with Aspergillus niger Lipase and Lactobacillus casei Aminopeptidase and Application of EMC on Accelerating Gouda Cheese Ripening By: Abdul Manab, Manik E. Sawitri, Khothibul Umam Al A. Animal Product Technology Department Faculty of Animal Husbandry, Brawijaya University This research was conducted from March until November 2008 in the Laboratory of Animal Product Technology - Faculty of Animal Husbandry, Laboratory of Agricultural Product Technology - Faculty of Agriculture Technology, Central Laboratory of Food Science and Technology - Brawijaya University and Laboratory of Molecular Biology - Faculty of Mathematic and Science, Brawijaya University. Laboratory of Matematic and Science Faculty of Mathematic and Science - Gadjah Mada University. The objective of this research was gouda cheese ripening acceleration using EMC which emulsified with lechitine. The objective of this research was gouda cheese ripening acceleration using EMC which emulsified with lechitine. Materials used were whey protein, beef tallow sapi, curd gouda cheese, L. casei, A. niger, A. niger Lipase, L. casei protease, maltodextrin, arabic gum. Equipment used were analitic balance (Ohaus BC Series dan Mettler Instruments, Perancis), pH meter (Hanna Instruments, Perancis), dan spektrofotometer UV (Thermospectronic Genesysttm 10 UV), water bathr, vortexmixer, autoclave, incubator, pipetman, GC, GCMS, HPLC (Hitachi), CLSM. The research method on A. niger Lipase production with beef tallow addition (0, 4 and 8%) and L. casei protease production with whey protein addition (0, 4 and 8%) using Completely Randomised Design. The measured variables were cell production, enzyme production and activity. The research method on EMC production with lipase addition (0, 0,3 and 0,6%) was Completely Randomised Design. The measured variables were fat content, Free Fatty Acid, Amino acid Profile, Fatty Acid Profile and EMC Flavour. The research method on EMC encapsulation with Maltodextrin and Arabic Gum (0, 3 and 6% respectively) were Completely Randomised Design. The measured variables were Lipase and protease activity, water content, flavour retention and microencapsulation retention. The research method on EMC Stabilisation during storage was Completely Randomised Design. The measured variables were Lipase and protease activity, Free Fatty Acid, peroxide, flavour, amino acid and fatty acid profile. Result of variance analysis indicated that treatment of beef tallow addition did not gave a significant effect (P>0.05) on A. Niger production, gave very significant effect (P<0,01) on lipase production and activity. Treatment of whey protein addition did not gave significant effect (P>0,05) on L. casei protease activity, however gave very significant effect (P<0,01) on protease production. Addition of A. niger lipase gave significant (P<0,05) on water content,and EMC fat content, gave very significant effect (P<0,01) on EMC FFA, however didnot gave significant effect (P>0,05) on EMC soluble protein. Arabic gum addition as encapsulation agent gave very significant effect (P<0,01) on water content, activity of EMC powder lipase and protease, however did not gave significan (P>,0,05) on EMC powder microencapsulation efficiency. Maltodextrin addition as encapsulation agent gave very significant effect (P<0,01) on

water content, activity of EMC powder lipase and protease, however did not gave significan (P>,0,05) on EMC powder microencapsulation efficiency. Storage of EMC powder increase lipase activity FFA and peroxide, change flavour, amino acid and fatty acid profile. Research showed that lechitine did not gave significant effect (P>0,05) emulsion stability of gouda cheese. Using of EMC did not gave significant effect (P>0,05) on water content, lipid content, TPC, lightness and yellowness of gouda cheese, gave highly significant effect on (P<0,01) on protease, lipase activity, LAB, FFA and texture gouda cheese and gave significant effect (P<0,05) on redness gouda cheese. Ripening time on EMC gave highly significant effect (P< 0,01) on water content, lipid content, protein content, pH, protease activity, lipase activity, LAB, TPC, FFA, Lighness, redness, yellowness and texture of gouda cheese. EMC 2% gave more compact microstructure and better potein-lipid distribution; more branched amino acid, more aromatic amino acid and more methionine; more short chain fatty acid; more flavor produced among ripening. Based on research concluded that beef tallow addition (8%) increase lipase production and activity, whey powder addition (8%) increase protease production and activity. Addition of lipase 0,6% produce better EMC characteristic. Using Maltodextrin 6% and arabic gum 3% produce better EMC powder (lipase and protease activity, efficiency microencapsulation). Storage EMC powder during 15 and 30 days increase lipase and protease activity, peroxide and FFA. It was suggested So produce EMC powder using 0,3% lipase and encapsulant agent (maltodextrin 6% or arabic gum 3%), storage EMC powder no more than 15 days on room temperature. It was suggested to research about EMC powder emulsification and application EMC powder on accelerating gouda cheese ripening. It concluded that: lechitine improve emulsion stability EMC powder in gouda cheese EMC; 2% EMC improve chemical composition (water, lipid, protein), decrease pH, LAB, TPC; increase FFA, lipase and protease activity, texture; improve lightness, redness and yellowness, more compact microstructure. EMC 2% accelaraed gouda cheese ripening. It suggested using EMC powder 2% on acceleration gouda cheese ripening.

RINGKASAN Pembangkitan Flavour Enzyme Modified Cheese (EMC) dengan Lipase Aspergillus niger dan Aminopeptidase Lactobacillus casei Serta Aplikasinya terhadap Percepatan Pemeraman Keju Gouda Abdul Manab, Manik E. Sawitri, Khotibul Umam A. Program Studi Teknologi Hasil Ternak Fakultas Peternakan Universitas Brawijaya ■

Penelitian ini dilakukan mulai bulan Maret 2008 sampai Nopember 2009 di Laboratorium Teknologi Hasil Ternak Fakultas peternakan, Laboratorium Sentral Ilmu Hayati Universitas Brawijaya. Laboratorium Biologi molekuler Fakultas MIPA Universitas Brawijaya, dan Laboratorium MIPA universitas Gadjah Mada. Penelitian Tahun I ini bertujuan peningkatan produksi enzim lipase melalui penambahan lemak s pada media pertumbuhan A. Niger, Peningkatan produksi enzim protease melalui penambahan whey bubuk pada media pertumbuhan L. Casei, Pembangkitan flavour EMC menggunakan lipase A. niger dan protease L. asei, Enkapsulasi enzim dan flavour EMC menggunakan maltodekstrin dan gum arab selama proses pengeringan, Stabilitas enzim lipase dan aminopeptidase serta retensi flavour EMC bubuk selama penyimpanan. Penelitian Tahun II ditujukan untuk percepatan waktu pemeraman keju gouda dengan penambahan EMC yang diemulsifikasi menggunakan lesitin. Materi yang digunakan dalam penelitian ini adalah protein whey, lemak sapi, curd keju gouda, L. Casei, A. niger, Lipase A. niger, protease L. casei, maltodekstri, gum arab. Peralatan yang digunakan di antaranya adalah timbangan analitik {Ohaus BC Series dan Mettler Instruments, Perancis), pH meter (Hanna InstrumentsvPerancis), dan spektrofotometer UV (Thermospectronic Genesysttm 10 UV), penangas air, vortex-mixer, autoclave, inkubator, pipetman, GC, GCMS, HPLC (Hitachi), Chromameter dan CLSM. Penelitian Tahun I produksi lipase dari A. niger dengan perlakuan lemak sapi (0, 4 dan 8%) dan protease L. casei dengan perlakuan protein whey (0, 4 dan 8%) menggunakan Rancangan Acak Lengkap. Variabel diuji pada penelitian ini adalah produksi sel, produksi dan aktifitas enzim. Produksi EMC dengan perlakuan lipase A. niger (0, 0,3 dan 0,6%) menggunakan rancangan acak lengkap, variabel yang diamati: kadar lemak, protein terlarut, kadar FFA, profil asam lemak, profil asam amino dan flavour EMC. Enkapsulasi EMC menggunakan maltodekstrin dan gum arab dengan perlakuan masing-masing (0, 3 dan 6%) dengan suhu pengering semprot 130°C menggunakan rancangan acak kelompok dengan variabel yang diamati kadar air, aktifitas lipase serta protease, efisiensi enkapsulasi dan retensi flavour. Penyimpanan EMC pada suhu ruang dengan waktu penyimpanan 1, 15 dan 30 hari dengan variabel yang diamati adalah aktifitas lipase dan protease, kadar FFA, Peroksida, profil asam lemak, asam amino dan stabilitas flavor. Penelitian Tahun II penggunaan lesitin keju gouda dengan mikrostruktur yang lebih kompak dengan sebaran lemak dan protein yanglebih merata; asam amino lebih banyak mengandung asam amino rantai cabang, mengandung sulfur dan aromatic; lebih banyak mengandung asam lemak rantai pendek serta mengandung flavor yang lebih banyak lebih cepat pembentukannya. Berdasarkan hasil penelitian Tahun I disimpulkan bahwa Penggunaan lemak sapi sebanyak 8% menghasilkan produksi lipase dengan aktifita yang lebih tinggi, dan protein whey

sebanyak 8% menghasilkan protease lipase dengan aktifitas yang lebih tinggi. Penggunaan lipase sebanyak 0,6% menghasilkan karakteristik EMC yang lebih baik. Penggunaan Maltodekstrin sebanyak 6% dan gum arab sebanyak 3% menghasilkan EMC bubuk dengan efisisensi enkapsulasi, aktifitas lipase dan protease yang lebih baik. Penyimpanan EMC bubuk pada suhu ruang selama 15 dan 30 hari berakibat pada peningkatan aktifitas lipase dan protease dan perubahan peroksida, FFA, Flavour, profil asam lemak dan asam amino. Disarankan Produksi EMC bubuk menggunakan lipase 0,3% dan dibutuhkan enkapsulan berupa maltodekstrin 6% atau gum arab 3% dan penyimpanan pada suhu ruang sebaiknya tidak melibihi 15 hari. Perlu kajian lebih lanjut tentang emulsifikasi EMC bubuk pada keju dan aplikasi EMC bubuk untuk percepatan pematangan keju gouda. Kesimpulan dari penelitian tahun ke-2 ini adalah: Penambahan lesitin dapat meningkatkan stabilitas emulsi EMC bubuk dalam keju gouda, Penambahan EMC bubuk sebanyak 2% berpengaruh pada komposisi kimia keju (kadar air, kadar lemak, kadar protein), menurunkan pH, jumlah BAL dan TPC, meningkatkan FFA, aktifitas protease dan lipase, membentuk struktur keju menjadi lebih kompak, memperbaiki warna Kecerahan (L), kemerahan (a) dan kekuningan (b) serta menghasilkan senyawa flavor lebih banyak dan lebih cepat, Penambahan EMC bubuk sebanyak 2% dapat mempercepat pematangan keju gouda. Disarankan untuk Percepatan pematangan keju bisa menggunakan penambahan EMC bubuk sebanyak 2%, Diperlukan penelitian lebih lanjut tentang karakterisasi peptida, MAG, DAG dan senyawa flavour yang potensial bagi kesehatafi.

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