analysis of food additives
DESCRIPTION
Analysis of Food additives. Abdul Rohman Bagian Kimia Farmasi, Fakultas Farmasi Universitas Gadjah Mada. Food additives are substances added to products to perform specific technological functions. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/1.jpg)
Analysis of Food additives
Abdul RohmanBagian Kimia Farmasi, Fakultas FarmasiUniversitas Gadjah Mada
![Page 2: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/2.jpg)
2
![Page 3: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/3.jpg)
• Food additives are substances added to products to perform specific technological functions.
• These functions include preserving, i.e. increasing shelf-life or inhibiting the growth of pathogens, or adding colouring and flavouring to food for interest and variety.
• There are over 300 permitted additives that can be used.
What are food additives?
![Page 4: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/4.jpg)
Types of additives
Additives may be:Natural – found naturally, such as curcumin, used as
a colouring agent;Manmade versions – synthetic such as benzoic acid
(E210), used as a preservative;
![Page 5: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/5.jpg)
5
Food additives
Preservatives Sweetener Colouring agents Antioxidants Flavor enhancer
![Page 6: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/6.jpg)
PreservativesPreservatives aim to:
Prevent the growth of micro-organisms which could cause food spoilage and lead to food poisoning;
Extend the shelf-life of products, so that they can be distributed and sold to the consumer with a longer shelf-life.
For example beef and other meats are often treated with nitrite and nitrate (E249 to E252) during the curing process.
![Page 7: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/7.jpg)
7
Pengawet Asam sorbat Asam benzoat Asam propionat Nitrit Sulfit
![Page 8: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/8.jpg)
8
Asam sorbat
tergolong asam lemak monokarboksilat yang berantai lurus dan mempunyai ikatan tidak jenuh (α-diena).
Bentuk yang digunakan umumnya garam Na- atau K-sorbat.
Asam sorbat digunakan sebagai pengawet dalam berbagai jenis makanan.
Asam sorbat menghambat pertumbuhan jamur dan pada umumnya ditambahkan ke bahan makanan dalam bentuk garamnya.
Asupan harian yang diterima (acceptable daily intake atau ADI) asam sorbat adalah 25 mg/kg berat badan.
H3C
O
OHasam sorbat
![Page 9: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/9.jpg)
9
Metode Analisis asam sorbatSpektrofotometri UvKromatografi GasKromatografi Cair Kinerja Tinggi
![Page 10: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/10.jpg)
10
Spektroskopi UV Asam sorbat mempunyai gugus kromofor (ikatan rangkap
terkonjugasi ) pada alfa-diena
Panjang gelombang maksimalnya kurang lebih 250 nm
![Page 11: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/11.jpg)
11Kromatografi Gas
![Page 12: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/12.jpg)
12
High Performance Liquid Chromatography
![Page 13: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/13.jpg)
13
Chromatographic conditionsColumn: a Supelco 516 C18 column (15 cm×4.6mm, 5µm)
at room temperature.
The detector used was UV-1570UV–vis spectrophotometer set at 254 nm
The mobile phase: methanol–acetate buffer (pH 4.4) (35:65, v/v) for 9min, after which it was changed to methanol–acetate buffer (pH 4.4) (50:50, v/v).
![Page 14: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/14.jpg)
14
![Page 15: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/15.jpg)
15
HPLC for analysis of sorbic acid
![Page 16: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/16.jpg)
16Asam benzoat
Asam benzoat digunakan sebagai pengawet pada berbagai macam makanan.
Asam benzoat menghambat pertumbuhan yeast dan jamur. Asupan harian yang diterima (acceptable daily intake atau
ADI) asam benzoat adalah 5 mg/kg berat badan
O
OH
asam benzoat
![Page 17: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/17.jpg)
17
Alkalimetri
O
OH
+ NaOHpp
O
ONa
+ H2O
O
ONa
HClO
OH
+ NaCl
![Page 18: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/18.jpg)
18
Spektrofotometri Benzoat dapat ditetapkan kadarnya secara
spektrofotometri karena benzoat mempunyai kromofor yang dapat menyerap sinar ultraviolet.
Dalam air, natrium benzoat akan mempunyai panjang gelombang maksimal 225 nm.
dalam air sebesar 665.%1cm1E
![Page 19: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/19.jpg)
19
Kromatografi Gas Dalam publikasi ilmiah biasanya dilakukan secara bersama-
sama dengan pengawet lain (seperti asam sorbat) Dilakukan ekstraksi dengan eter Derivatisasi kolom 1,8 m x 2 mm i.d yang dilapisi dengan OV-1 (100 –
120 mesh). Suhu operasional, oven: 80 – 2100C dengan kenaikan
80C/menit; Injektor 2000C; detekor ionisasi nyala (FID) 2800C. Gas pembawa: nitrogen dengan kecepatan alir 20 mL menit.
Waktu retensi asam kaproat, asam sorbat, asam benzoat, dan asam fenilasetat masing-masing kurang lebih 2,5; 4; 5; dan 6 menit.
![Page 20: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/20.jpg)
20HPLCHPLC method for benzoic acid applicable for foodstuffs containing benzoic acid in the range 50–2000 mg/kg.The following conditions have been shown to be satisfactory.
Elution order:benzoic acidsorbic acidmethyl 4-hydroxybenzoateethyl 4-hydroxybenzoatepropyl 4-hydroxybenzoate
![Page 21: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/21.jpg)
21Nitrit Garam nitrit umumnya digunakan untuk proses curing daging
untuk memperoleh warna yang baik dan mencegah pertumbuhan mikroba.
Penggunaan natrium nitrit dalam ikan dan daging ternyata menimbulkan efek yang membahayakan kesehatan.
Nitrit dapat berikatan dengan amino atau amida dengan membentuk turunan nitrosamin yang bersifat toksik (karsinogenik).
R2NH + N2O3 R2N.NO + HNO2
R3N + N2O3 R2N.NO + Ramin sekunder
amin tersier
nitrosamin
nitrosamin
![Page 22: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/22.jpg)
22
Metode Griess I Prinsip penetapan kadar nitrit dengan metode Griess I ini
adalah reaksi diazotasi antara asam nitrit (dari nitrit dalam suasana asam) dengan amin aromatis primer (asam sulfanilat).
Garam diazonium yang dihasilkan dari reaksi diazotasi ini selanjutnya direaksikan (dikopling) dengan alfa-naftilamin membentuk senyawa berwarna yang dapat diukur pada panjang gelombang 520 nm.
![Page 23: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/23.jpg)
23
Reaksi pada penentuan Griess I
NO2-
nitrit (dalam bahan makanan)
H+HNO2
asam nitrit
HNO2 + S
O
O
OHH2N
asam sulfanilat
S
O
O
OHN+
garam diazonium
N
S
O
O
OHN+
N + H2N
-naftilamin
N NS
OH
OO
senyawa kopling (520 nm)
H2N
![Page 24: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/24.jpg)
24Metode Griess II
Metode Griess II prinsipnya hampir sama dengan metode Griess I.
Sebagai amin aromatis primer, metode Griess II ini menggunakan sulfanilamid sementara agen pengkoplingnya adalah naftiletilendiamin (NED).
![Page 25: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/25.jpg)
25Reaksi pada analisis nitrit dengan Griess II
NO2-
nitrit (dalam bahan makanan)
H+HNO2
asam nitrit
HNO2 + S
O
O
NH2H2N
sulfanilamid
S
O
O
NH2N+
garam diazonium
N
S
O
O
OHN+
N +
naftiletilen diamin (NED)
N NS
OH
OO
senyawa kopling (545 nm)
NHCH2CH2NH2
H2NH2CH2CHN
![Page 26: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/26.jpg)
26Method development
![Page 27: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/27.jpg)
27
Summary for nitrite determination
![Page 28: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/28.jpg)
28ContohSebanyak 25,0 gram sampel daging ditimbang secara saksama, digerus, lalu ditambah dengan air bebas nitrit suhu 800C sampai volumenya ± 300 mL, dimasukkan dalam labu takar 500 mL lalu memanaskannya di atas penangas air 800C selama 2 jam sambil sesekali digoyang, dan ditambah air sampai batas tanda. Sebanyak 20,0 larutan hasil penyaringan dipipet lalu dimasukkan ke dalam labu takar 50 mL, ditambah 2 mL pereaksi Griess, dan diencerkan dengan air bebas nitrit sampai batas tanda. Larutan dibiarkan selama 1 jam supaya terbentuk warna. Larutan dibaca absorbansinya pada panjang gelombang 520 nm terhadap blanko, dan mempunyai nilai absorbansi sebesar 0,215 nm. Sebanyak 100,0 mg standar NaNO2 dilarutkan dengan air bebas nitrit sampai 100,0 ml. Sebanyak 1,0 mL larutan ini diambil, ditambah 2mL pereaksi Griess dan ditambah dengan air sampai 50,0 mL. Larutan ini dibaca absorbansinya di 520 nm dan mempunyai absorbansi sebesar 0,250. Berapakah kandungan nitrit dalam sampel daging diatas.
![Page 29: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/29.jpg)
29
Sulfit Sulfit digunakan sebagai pengawet dalam bentuk SO2,
garam Na- atau K-sulfit, danbisulfit.
Bentuk efektifnya sebagai pengawet adalah dalam bentuk tidak terdisosiasi pada pH di bawah 3.
The acceptable daily intake (ADI) for sulphites (expressed as sulphur dioxide) is 0.7 mg/kg body weight
![Page 30: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/30.jpg)
30
Analisis Sulfit
Titrimetric (Monier–Williams method) enzymatic
![Page 31: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/31.jpg)
31
Monier–Williams method The test portion is heated with a refluxing solution of
hydrochloric acid to convert sulphite to sulphur dioxide.
Sulphur dioxide is oxidized with hydrogen peroxide to sulphuric acid.
The generated sulphuric acid is titrated with standardized sodium hydroxide solution.
The sulphite content is directly related to the generated sulphuric acid
![Page 32: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/32.jpg)
32Enzimatis Sulphite was oxidized to sulphate in the presence of sulphite
oxidase with the liberation of hydrogen peroxide at the same time.
![Page 33: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/33.jpg)
33
![Page 34: Analysis of Food additives](https://reader033.vdocuments.net/reader033/viewer/2022061610/56816614550346895dd95f57/html5/thumbnails/34.jpg)
34