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PROTEIN WEEK-4. SBW. Cellular Protein Synthesis. DNA: in nucleus: acts as a template for mRNA mRNA moves out of nucleus to cytoplasm Carries instruction for an amino acid sequence for a specific protein to a ribosome Ribosome ‘reads’ the mRNA which dictates which amino acid is next
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PROTEIN WEEK-4 SBW
Cellular Protein Synthesis DNA: in nucleus: acts as a template for mRNA mRNA moves out of nucleus to cytoplasm Carries instruction for an amino acid sequence for a specific protein to a ribosome Ribosome ‘reads’ the mRNA which dictates which amino acid is next tRNA carries the correct amino acid to the mRNA
Cellular Protein Synthesis tRNA’s line up one after the other with amino acids Amino acids form peptide bonds to make the primary sequence of the protein Protein then coils to form the secondary and tertiary structure SHAPE DETERMINES FUNCTION
Protein Digestion Stomach Denaturation Pepsin induced breakdown into shorter ‘peptides’ Small Intestines duodenum: peptidases or proteases enter from pancreas thru the common bile duct breakdown proteins to aa’s, dipeptides and tripeptides
Protein Digestion Cells of small intestine complete digestion of proteins so that only amino acids remain cells of S.I. absorb amino acids and a few larger peptides and release them into the blood for circulation
Protein Function • Structure proteins • Muscle fiber protein • Connective proteins • others
Protein: Function Supporting Growth and Maintenance body needs amino acids to grow new cells and replace cells that are worn out
Protein: Function Building Enzymes, Hormones, and other Compounds amino acids used to make enzymes (e.g.. lipases for digestion) amino acids used to make some hormones(e.g.. insulin for glucose metabolism)
Protein: Function Building Antibodies antibodies are formed from amino acids to defend against foreign proteins and substances in the body Maintaining fluid and electrolyte balance Proteins act like magnets and hold water in the blood vessels and also electrolytes like sodium
Transport Proteins Cellular content differ from the contents of the surrounding environment: fluids and electrolytes Protein Membrane carriers provide a ‘pump’ to maintain this difference Sodium-Potassium Pump Animation of the Sodium-Potassium Pump
Vegetarian reduced risk obesity diabetes hypertension heart disease digestive disorders cancer Meat eaters growth support during critical times. Vegetarian vs Meat eaters
Protein Rich Foods Animal products also high in vitamin B12, iron, and zinc lacking in vitamins C and folate often high in fat Legumes soy protein almost “complete” high in fiber, many B vitamins, iron, calcium low in vitamins A, C and B12
Protein Needs 154# (70 kg) RDA = 70 x .8g/kg = 56 grams Athlete 1 to 1.5 g/kg (ADA)= 70 to 105 grams Protein/day
Too little Protein Kwashiorkor: Protein deficiency true definition: what happens to the first child when the second child is born symptoms: edema, ascites(swollen belly) immune system failure so many infections loss of pigmentation Phenylalanine to Tyrosine to Melanin is blocked Fatty Liver no lipoproteins to carry fats and accumulate in liver
SIFAT FISIKO-KIMIA GLUTEN • GLUTEN BASAH DIPEROLEH, BILA ADONAN TEPUNG GANDUM (MERK CAKRA BIRU DITAMBAHKAN AIR, MEMBENTUK ADONAN • ADONAN DICUCI DENGAN AIR MENGALIR, AKAN DIPEROLEH BENDA YANG MOLOR, DISEBUT GLUTEN • KOMPOSISI GLUTEN
GLUTEN BASAH • AIR 70%, PROTEIN 22%, LEMAK 2% DAN KARBO 6% • GLUTEN KERING: AIR 10%, PROTEIN 72%, LEMAK 4% DAN KARBO 14% • SIFAT FISIKO-KIMIA GLUTEN: LARUT AIR MEMBENTUK ADONAN YANG ELASTIS KUAT, KENYAL, KARENA MEMILIKI IKATAN DISULFIDA YANG BANYAK.
DAGING • KOMPOSISI KIMIA DAGING: • 1. MYOFIBRIL (OTOT KONTRAKSI): MYOSIN, ACTIN, TROPOMYOSIN, TROPONIN (9.5% bb) • 2. Stroma (OTOT PENGIKAT DAGING, 3% bb): COLAGEN • 3. SARCOPLASMA (CAIRAN DIANTARA SEL DAGING): ENSIM2, MYOGLOBIN, HEMOGLOBIN, CYTOCHROME DAN FLAVO-PROTEIN (6% bb)
SIFAT FISIKO-KIMIA DAGING • 1. DAGING TIDAK LARUT DALAM AIR: KARENA MEMILIKI COLAGEN, BILA DIPANASKAN DAN MENGERING, KOLAGEN AKAN MENGERAS DAN TIDAK TEMBUS AIR, KARENA ITU KOLAGEN SEBAGAI CASING SOSIS ALAMI. KOLAGEN SIFATNYA NON-POLAR. KOLAGEN DIGUNAKAN SEBAGAI PENGHASIL GELATIN, LENSA KONTAK MATA, CASING ALAMI SOSIS. JARINGAN IKAT DAGING BANYAK MENGANDUNG GLYSIN DAN HIDROKSIPROLIN (NON-POLAR, pH nya 7.2) • 2. DAGING MAMPU MENAHAN AIR, KARENA BANYAK MENGANDUNG SENYAWA POLAR SEPERTI: MYOSIN/ACTIN • 3. SARCOPLASMA, banyakmengandungensim, cairandarahdan aroma dagingterlarut di cairandaging. Aroma dagingakanberubahbilaterjadi proses hidrolisis protein akibataktifitas ensim-2 di cairandaging (Sarcoplasma protein)
Fresh meat: dagingsegar is ALIVE. • Menggunakan O2 danmenghasilkan CO2 UNTUK MENDAPATKAN ENERGI AGAR SUPAYA ENSIM TETAP BEKERJA DAN KEMAMPUAN MEREDUKSI SENYAWA SECARA ENSIMATIS TETAP BERJALAN. • NAMUN SUPPLY OKSIGEN BERHENTI, KETIKA TERNAK DIPOTONG.
REAKSI MAILLARD PROTEIN • Occurs between reducing sugars and amines at high temperatures • Produces flavor • Produces color • Produces antioxidant products • Produces toxic products • Destroys nutrients (lysine)
SIFAT FUNGSIONAL PROTEIN PROF SBW
Kelarutan • adalahkemampuansuatuzatuntukbisalarut. Suhumempengaruhikelarutankarenadipengaruhiolehwujudzat. • Semakinbesarsuhumakakemampuansenyawauntuklarutakansemakintinggi. • Namununtukmolekul protein bilasuhudinaikkanmaka protein akanterdenaturasi. Protein akanmengendap/terdenaturasi
Faktor yang mempengaruhikelarutan protein adalah: • pH, kekuatanionik (pemberiangaram), suhudantekanan.
SIFAT KELARUTAN PROTEIN Uji Kelarutan Protein Terhadap Pemanasan AIR MENDIDIH
Sifatpembuihan protein • BUIH CAIR • Buihterjadibila protein albumin/putihtelur di aduk/mixer/whipping. • Telurdengankadar albumin tinggidankentalmenhasilkanbuih yang lebihkakudanlebih lama waktumixernya • Bilaputihtelurdikeringkan, sifatbuihnyahilang
Stabilitasbuihtergantungpada • Viskositas • Resistensiterhadapgayageser • KEKUATAN IONIK
BUIH CAIR • Alatpemadamkebakaranmengandungcampuran air, natriumbikarbonat, aluminiumsulfat, sertasuatuzatpembuih. Karbondioksida yang dilepasakanmembentukbuihdenganbamtuamzatpembuihtersebut. • BUIH PADAT: ROTI
PENGEMULSI • MOLEKUL PROTEIN AKAN TERDISPERSI DALAM FASE PENDISPERSI DALAM BERBAGAI BENTUK, SEPERTI: • EMULSI CAIR: SUSU, MAYONES, KRIM • EMULSI PADAT: KEJU, GELATIN, • PERHATIKAN KESTABILAN KOLOID PROTEIN DALAM FASE PENDISPERSINYA, SISTEM KOLOID INI MEMERLUKAN SURFAKTAN/ZAT PENGEMULSI, AGAR STABIL pada SISTEM KOLOID O/W (hidrofilik) spt: Tween 20, atau Tween 80 • Sistem W/O (LIPOFILIK): GLISERIL MONOSTEARAT atau SPAN 20, SPAN 80 (SORBITAN MONOLAURAT).
PEMBENTUKAN GEL • MOLEKUL PROTEIN MEMBENTUK GEL, SESUDAH PENDINGINAN • MEKANISME GEL PROTEIN: • CONTOH: GELATIN • PENAMBAHAN KATION (Ca2+) akanmemperkuat gel, bisa pula ditambahkan Al3+
MEKANISME GEL PROTEIN • CONTOH: GELATIN • GELATIN TERSUSUN ATAS 300 - 4000 amino acids
GELATINE PRODUCTS Gelatin kuning & putih dari PIG SKIN Gelatin in spoon from PIG SKIN GELATINE HALAL FROM COW SKIN/BONE.