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PPT. MATKUL KIMPANG

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  • KOMPOSISI DAN SIFAT BAHAN PANGANWaterProteinCarbohydrateLipida Vitamin &Mineral Komponen Alami:Komponen Tambahan:Emulsifier Antioxidant Preservative Thickener Sweetener Etc. MUTU & KEAMANANPANGANEnzimAntioksidanAsamPigmenCitarasa

  • KARBOHIDRAT PENDAHULUAN KARBOHIDRAT DALAM BAHAN PANGAN KLASIFIKASI DAN STRUKTUR KIMIA REAKSI KIMIA KARBOHIDRAT SIFAT FUNGSIONAL KARBOHIDRAT

  • 1. PENDAHULUAN75 % of Biological World80 % of the Calorie Intake of humankind75 80 % starchIn USA : Composition of Calorie IntakeCarbohydrate : 46% 47 % Starch52% SucroseFats : 42%Protein : 12%Rumus Umum : Cx(H2O)yModifikasi struktur Sifat Fungsional

  • 2. KARBOHIDRAT DALAM BAHAN PANGANKarbohidrat utama dalam :animal : glucose, glycogenmilk: lactose plant : cellulose, starchseaweed: alginate, carrageenan, agar

  • 2. KARBOHIDRAT DALAM BAHAN PANGAN

    FoodSugar (%) Coke Crackers Ice Cream Orange Juice Cake (dry mix)912181036

  • Sugar in Fruits :

    FruitFree Sugar (%)GlucoseFructoseSucrose Apple Grape Peach Pear Strawberry1.176.860.910.952.096.047.841.186.772.403.782.256.921.611.03

  • Sugar in Vegetables:

    VegetablesFree Sugar (%)GlucFrucSuc Broccoli Carrot Cucumber Spinach Sweetcorn Tomato0.730.850.860.090.341.120.670.850.860.040.311.340.424.240.060.063.030.01

  • Sugar in Legumes :

    LegumesFree Sugar (%)GlucFrucSuc Snap bean Lima Bean Pea1.080.040.321.200.080.230.252.595.27

  • Sugar in Fruits (per 100 gram)Sumber : Food and Nutrition Encyclopedia (1994) *) Daftar Analisis Bahan Makanan (1992)

    Macam BuahJumlah Gula (%)Jenis Gula (g)Energi (kcal)GlucFrucSuc Kurma Pisang Kismis Apel Nanas Anggur Pear Jeruk Manis Mangga Blewah48.819.614.211.010.69.38.78.57.46.524.95.2-1.22.34.82.52.5-1.123.95.9-6.01.44.35.01.8-1.3-8.514.23.86.90.21.24.27.44.127198 *)28964 *)57 *)686151 *)73 *)30

  • 3. KLASIFIKASI DAN STRUKTUR KIMIAPhotosynthesisCarbohydrates are synthesised in green plants by photosynthesis. Solar energy is absorbed by the green pigment in plants, chlorophyll. This energy is used to drive many enzyme-catalysed processes. The overall effect is to reduce carbon dioxide to carbohydrates and oxidise water to oxygen:LingkunganTanamanLingkungan

  • Energi dan Analisis KH. Tiap molekul heksosa akan membebaskan 675 Kal dalam reaksi kebalikan dari fotosintesis. 1 mol Heksosa menjadi CO2 dan H2O menghasilkan energi 675/180 = 3,75 Kal per gram

    . Pembakaran sukrosa memberikan 3,95 Kal per gram. Efisiensi pencernaan sukrosa 98% shg kalori yg dihasilkan untuk tubuh dari 1 gr sukrosa : 3,95 x 0,98 = 3,87 Kal per gram

  • Energi dan Analisis KH. Bila tjd polymerisasi, bbrp molekul heksosa membentuk homoglikan (Exp. Pati (C6H6O5)x dihasilkan 4,18 Kal per gram. Efisiensi pencernaan pati 98-99% maka 1 gr KH : 0,98 x 4,18 = 4,0 Kal

    . Analisa KH dg proximate analysis : analisa dimana kandungan KH termasuk SK diketahui mll perhitungan% KH = 100% - % (Protein+Lemak+Abu+Air)

    . Analisa dg Carbohydrate by Difference : penentuan KH dlm makanan scr kasar dan hasilnya dicantumkan dlm Daftar Komposisi Bahan Makanan

  • CARBOHYDRATE Cx(H2O)yMonosaccharidesPOLYSACCHARIDESDisaccharidesHexose (C-6)Pentose (C-5)D-GlucoseD-GalactoseD-MannoseD-FructoseXyloseArabinoseRiboseSucrose (a+d)Lactose (a+b)Maltose (a+a) -> aCellobiose (a+a) ->bOligosaccharidesRafinose (b+a+d)Stachyose (b+b+a+d)VerbacoseCellulose (-> a)Starch (-> a)Chitin Agar (->b)Carrageenan (->b)Alginat

  • POLYSACCHARIDESSTARCHNON-STARCHPOLYSACCHARIDESAlginateCarrageenanAgarFurcellaranDaratan:CellulosePectinPerairan:ChitosanGumLainnyaLainnya

  • Struktur KimiaCOHHCCCCCHHHHOOHOHHHOHOH=OHHOOHOHOHHCH2OHHHa-D-Glukosa123456123456a-D-Glukosa(Aldosa)(Aldohexose)Gugus Karbonil (CO)Gugus Aldehid (CHO) = gugus reduksiAtom C asimetris terjauh dari karbonil (CO)Sebagai dasar penamaan D (OH dikanan) dan L (OH di kiri)HOH1bAtom C Chiral

  • Struktur Kimia

  • Struktur KimiaCOHHCCCCCHHHHOOHOHHHOHOH=OHHOOHOHOHHCH2OHHHa-D-GlukosaKonfigurasi Haworth123456123456Aldehydo-D-Glukose

    COHHCCCCCHHHHOOHOHHOHHOH123456a-D-Glucopyranosa

  • Struktur KimiaCOHHCCCCCHHHHOOHOHHHOHOH=123456a-D-Glukosa(Aldosa)Gugus Karbonil (CO)Gugus Aldehid (CHO) = gugus reduksiCOHHCCCCCHHHHOOHOHHHOHHOH123456HReduksiSorbitol Na-Amalgam Li-Al-hydride hydrogenation

  • Struktur KimiaCOHHCCCCCHHHHOOHOHHHOHOH=123456a-D-Glukosa(Aldosa)(Hexose)(C6H12O6)Gugus Karbonil (CO)Gugus Aldehid (CHO) = gugus reduksiCOHCCCCCHHHOOHOHHHOHHOH123456H=a-D-Fruktosa(Ketosa)(Hexulose)(C6H12O6)Gugus KetonROHCCHO=R = H AldehydeR = CH2OH KetonSaccharose group

  • Struktur KimiaCarbonyl group

    Keton Aldehid Aldehydes are readily oxidised to carboxylic acids:If copper (II) (blue Cu2+) is used as the oxidising agent it is converted into copper (I) which forms red copper oxide (Cu2O) as a precipitate. This is how Benedicts reagent and Fehlings solution are used to test for aldehydes and reducing sugars.

  • Struktur Kimia

  • OHHOOHOHOHHCH2OHOHHOOHOHOHHCH2OHOHOHOHOHOHHCH2OHHHHHHHa-D-Glukosaa-D-Manosaa-D-GalaktosaOOHCH2OHOHCH2HOHOHH123456123456a-D-FructoseHMONOSAKARIDAaaaa

  • OHHOOHOHOHCH2OHHHa-D-Maltosa(Glukosa-a-(14)-Glukosa)OHOHOHOHHCH2OHHHDISAKARIDAa-D-Glukosaa-D-Glukosa terdiri atas 2 molekul glukosa dari hydrolysis pati oleh b-amylase gula reduksi

  • OLactosaGalaktose-b-(14)-Glukosa)OHOHOHOHHCH2OHHHDISAKARIDAa-D-Glukosa terdiri atas Galaktosa dan Glukosa terdapat pada susu : Mamalia : 2 8.5% Cow and Goat : 4.5 4.8% Human : 7 % gula reduksiOHOHOHOHHCH2OHHHa-D-Galaktosa

  • SukrosaGlukosa-a-(12)-Fruktosa)DISAKARIDA terdiri atas Glukosa dan Fruktosa terdapat pada cane atau beet gula non-reduksi table sugarOHHOOHOHOHCH2OHHHa-D-GlukosaOOHCH2OHOHCH2OHOHH123456a-D-FructoseH

  • Jenis Oligosakarida yang banyak terdapat di AlamOligosakarida adl polimer dg derajat polimerisasi 2 10 dan biasanya larut dalam air

    Derajat PolimerisasiHomo-Reduktif (gugus OH)Homo-Non ReduktifHetero-ReduktifHetero-Non Reduktif2Selobiosa Isomaltosa GentibiosaTrehalosaLaktosa Laktulosa Maltulosa MelibiosaSukrosa3MaltotriosaRafinosa4MaltotetrosaStakiosa5MaltopentosaVerbakosa6 - 10MaltoheksaDekstrinSchardingerAjukosa

  • POLISAKARIDADalam bhn makanan berfungsi :sbg penguat tekstur (selulosa, hemiselulosa, pektin, lignin)-sbg sumber energi (pati, dekstrin, glikogen, fruktan)

  • PATI Homopolimer glukosa dg ikatan -glikosidikTdr dr fraksi yg dipisahkan dg air panas :a/ fraksi terlarut (AMILOSA)b/ fraksi tidak larut (AMILOPEKTIN)Semakin kecil amilosa / semakin tinggi amilopektin Nasi semakin lengketBeras ketan (amilosa 1-2%), Beras biasa (amilosa > 2%)Nasi /beras terbagi 4 gol : (1) amilosa tinggi (25-33%); (2) amilosa menengah (20-25%) ~ orang Indonesia, Mlaysia, Philipina, Thailand; (3) amilosa rendah (9-20%) ~ orang Jepang & Korea; (4) amilosa sangat rendah (
  • Granula pati dari beberapa komoditi (Martin, 1979)

  • GELATINASIBila pati mentah dimasukkan air dingin, granula pati menyerap air (makssimal 30%) & membengkak Peningkatan volume granula pati dalam air (suhu 55-65C. Granula pati dibuat membengkak tapi tdk bisa kembali pd kondisi semula : GELATINASISuhu gelatinasi (diukur dg viskosimeter & polarized microscope) pada jagung 62-70C, beras 68-78C, gandum 54,5-64C, kentang 58-66C, tapioka 52-64C

  • Granula pati mempunyai sifat merefleksikan chy terpolarisasi shg di bwh mikroskop terlihat kristal hitam putih : sifat BIREFRINGENT

    Kisaran suhu yg menyebabkan 90% butir pati dlm air panas membengkak shg tdk kembali lagi ke bentuk normal : BIREFRINGENT END POINT TEMPERATURE (BEPT)

    BEPT rendah 55-69CBEPT medium70-74CBEPT tinggi 75-77C

  • Proses kristalisasi kembali pati yang telah mengalami gelatinasi : RETROGRADASI

    Keluarnya atau merembesnya cairan dari suatu gel dari pati : SINERESIS

    Enzim yg dapat menghidrolisis pati : -amilase, -amilase & fosforilase

    Bagian pati yang tidak terurai menjadi residu karena -amilase tidak mampu menghidrolisis amilopektin di luar batas (hanya 60-70%) : -amilase limit dextrin

    Pati + PO43-fosforilase-D-glukosa-1-fosfat

  • OHOHOHCH2OHHOHOHOHHCH2OHHHCELLULOSEa-D-Glukosaa-D-GlukosanPOLISAKARIDAikatan-b-(14)-Glikosidik)OHOHOAABBO1421441

  • POLISAKARIDA

  • POLISAKARIDA

  • REAKSI-REAKSI KARBOHIDRAT HYDROLYSIS NON-ENZYMATIC BROWNINGAs shown in Table 4.29, the C1 and Cx factors, which were found to be endo- and exo-1,4--glucanases respectively, hydrolyze cellulose to cellobiose. Since the C1 factor is increasingly inhibited by its product, a cellobiase is needed sothat cellulose breakdown is not rapidly brought to a standstill. However, cellobiase is also subject to product inhibition. Therefore, complete cellulosedegradation is possible only if cellobiase is present in large excess or the glucose formed is quickly eliminated.

  • REAKSI-REAKSI KARBOHIDRAT HYDROLYSIS : Pembuatan HFCS (High Fructose Corn Syrup)POLYSACCHARIDESAcid TreatmentHeat TreatmentEnzyme Treatment123PRODUCTSHFCS

  • 4. REAKSI-REAKSI KARBOHIDRAT HYDROLYSIS : Fermentasi TapeBAHAN BAKUFermentation Jenis Mikrobia Suhu WaktuPRODUCTS Ketela Pohoh Ketan Tape singkong Tape KetanStarchGlucoseAlcoholAcid

  • BROWNING ENZIMATIS NON-ENZIMATIS Reaksi Enzimatis Dipengaruhi oleh : Substrat Enzim Suhu Waktu Reaksi Maillard Karamelisasi Reaksi Gula & Protein Dipengaruhi oleh : Jenis Gula Suhu Waktu Pemanasan Gula Dipengaruhi oleh : Suhu Waktu Ascorbic acid oxidation

  • BROWNING Reaksi Maillard Ilmuwan Perancis : Louis Maillard (1912) glucose + glycine Carbonyl Amine Reaction action of amino acids/protein on reducing sugars Related to aroma, taste and color Roasting of coffee and cacao beans, baking of bread and cakes, toasting of cereals, cooking of meats

  • BROWNING REDUCINGSUGARAMINOACIDCARBONYLAMINEMelanoidins (Brown Pigments) Dipengaruhi oleh : Jenis Gula Asam Amino pH Suhu Katalis Kadar Air5-Hydroxymethyl-2-Furfuraldehyde(HMF)

  • REAKSI MAILLARDReaksi antara gula pereduksi dan Protein (asam amino)Dipengaruhi oleh suhu, waktu dan jenis gulaMenghasilkan warna coklat Prosesnya berlangsung pada suasana basaProses yang terjadi pada reaksi maillard:Gugus karbonil pada gula menghasilkan N-glukosamin dan airGugus glukosamin yang tidak stabil mengalami pengaturan kembali membentuk ketosaminKetosamin mengalami proses lanjut:Memproduksi air dan reduktonMenghasilkan diasetil, aspirin, pyruvaldehid, dan ikatan hidrolitik lainMembentuk melanoidin.

  • MAILLARD REACTION (i) Initial stage (colourless)a. sugar-amine condensationb. Amadori rearrangement(ii) Intermediate stage (colourless to yellow)c. sugar dehydrationd. sugar fragmentatione. amino acid degradation(iii)Final stage (highly coloured)f. aldol condensationg. aldehyde-amine polymerisation, formation of heterocyclic nitrogen compounds.

  • Maillard Reaction Fig. 1. Effect Temperature on the reaction rate of D-Glucose with DL-Leucine

  • Maillard Reaction Fig. 1. Effect pH on the reaction rate of D-Glucose with DL-Leucine

  • BROWNING REACTIONSSUCROSESUCROSE +FRUCTOSESUCROSE +LACTOSEMaillard Reaction : (Lysine + Sugars)

  • BROWNING NON ENZIMATIS : MAILLARDProduk : Bakpia

  • CARAMELIZATIONCaramelization is defined as the thermal degradation of sugars leading to the formation of volatiles (caramel aroma) and brown-colored products (caramel colors). The process is acid or base catalyzed and generally requires temperatures > 120 oC at 9
  • TEKNOLOGI KARBOHIDRATSUMBERKARBOHIDRATTEKNOLOGIPROSESCARBOHYDRATE-BASEDPRODUCTKetela PohonBeras KetanJagungGandumTape Ketela PohonTape KetanHFCS (High Fructose Corn Syrup)4. Karamel5. Candy6. Modified (CMC)AsamBasaPanasEnzimatisMikrobiologis

  • SIFAT FUNGSIONALSWEETNESS & SWEETENERSHYGROSCOPICITYReduced Aw PreservativeAdsorbent Baby care productsMoisture Beauty care productsTEKSTURAL CONTRIBUTIONRigidity : RotiViscosity: Saus

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