Pre Treatment of milk (before processing system become a product) Each of pruduct must a specific pretreatment. Can be improved of product quality

Transkripsi

1 Firman Jaya

2 Pre Treatment of milk (before processing system become a product) Each of pruduct must a specific pretreatment Can be improved of product quality 2

3 MILK PRE TREATMENT 1 CLARIFICATION 2 SEPARATION 3 HOMOGENIZATION 4 BACTOFUGATION 5 THERMIZATION 6 PASTEURIZATION

4 Raw milk still contains unwanted foreign substances, such as contaminants from the air and dirt from contact with the milking machines Milk should be clarified to improve milk quality or to ensure that milk and dairy products are brought into circulation only in perfect condition which will not harm health. 4

5 Raw Milk Milk Cleaning Clarifier Unwanted Solids Clarified Raw Milk 5

6 Alat yang digunakan: 1. Penyaring 2. Clarifier 3. Centrifugal Separation IPS - KLARIFIKASI : memindahkan kotoran padat dari susu - SKIMMING : pemisahan krim dari skim - PEMISAHAN WHEY : pemisahan lemak dari whey - BACTOFUGE TREATMENT: pemisahan bakteri dari susu - PEMISAHAN QUARG : pemisahan curd quarg dari whey - PEMURNIAN BUTTER OIL: pemisahan fase serum dari anhydrous milk fat 6

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8 Filtration used to clarify fluid foods and to remove microorganisms from either air or fluid foods and to separate solid from liquid phase Filtration involves passing a material through a filter medium that retains particles of a certain size ex: separation cheese curd from whey 8

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11 Centrifugation Separation of cream from milk Separation of the fat in milk is also accomplished using a centrifugal separator In this case, whole milk containing about 3.8 to 4.3% milk fat enters the centrifuge, where the fat phase is separated from the aqueous phase by centrifugal force based on their different densities. The fat phase is only concentrated, and not separated entirely, to produce cream with about 30% fat. The remainder of the cream is basically the same as the skim milk, which is the other product from the centrifuge. In a centrifuge, the fat content of milk may be reduced to less 0.1%. 11

12 Cream Separation by Centrifugation

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14 Pemisahan Krim Fat globules (lower density, spheres) Skim milk (higher density, fluid)

15 Krim Skim

16 Removal of non-milk constituents and somatic cells Removal of bacteria and spores, in particular Bacillus cereus Multiple use (for cheese-making milk and ESL milk) ESL milk has properties equivalent to those of traditional fresh milk 16

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18 Proses pemecahan globula lemak sehingga menjadi globula lemak yang berukuran kecil dan seragam Tujuan: 1. untuk memperlambat proses pemisahan krim pada saat susu disimpan 2. meningkatkan kekentalan susu 3. meningkatkan ketahanan terhadap terjadinya penggabungan partikel (coalescence) 18

19 Homogenisasi akan menaikkan viskositas dan memberikan kesan bahwa kandungan lemaknya lebih tinggi Menaikkan daya cerna Lemak susu yang telah mengalami homogenisasi memiliki globula yang lebih kecil, sehingga mudah menglami kerusakan karena hidrolisis (karena adanya enzim lipase) ataupun karena oksidasi. 19

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21 Homogenisasi dilakukan dengan menggunakan homogenizer 1. Tipe bertekanan tinggi (high-pressure type) Tekanan antara pon/inci persegi 2. Tipe bertekanan rendah (low-pressure- rotary type). Tekanan di bawah 500 pon/inci persegi 3. Tipe gelombang suara (sonic-vibrator atau ocillator)

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23 Tahapan proses homogenisasi dapat dilakukan dengan : 1.Single stage homogenization, digunakan untuk homogenisasi: - Produk dengan kandungan lemak rendah - Produk yang memerlukan homogenisasi berat (heavy) - Produk yang memerlukan viscositas tinggi 2.Two stage homogenization, digunakan untuk: - Produk dengan kandungan lemak tinggi -Produk dengan kandungan bahan kering (konsentrasi susu) tinggi - Produk dengan viscositas rendah.

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25 Bactofugation is a process of separation of spores and bacterial cell of cheese milk prior to heat treatment which can severely affect the quality of the cheese It has pricipally been used to remove spores from cheese milk that could cause latent fermentation in semi-hard cheeses Used most commonly in production of Swiss cheese 25

26 Now, it has been adapted for processing consumption milk, where it holds out the promise of prolonging the life of fresh, pasteurised milk (3-5 days) Bactofugation Bactofuge (is a centrifuge like machine to remove bacteria and spores from milk to a large extent prior to heat treatment in order to improve the thermal impact) Bactofugation process can removes 95% of spores of milk 26

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28 Thermization, also spelled thermisation, is a method of reducing microorganism of raw milk with heat. The process is not used on other food products, and is similar to pasteurization but uses lower temperatures, allowing the milk product to retain more of its original taste 28

29 Thermization involves heating milk at temperatures of around F (63 65 C) for 15 seconds, while pasteurization involves heating milk at 160 F (71 C) for 15 seconds or at 145 F (63 C) for 30 minutes.

30 Pasteurisasi susu adalah pemanasan susu di bawah temperatur didih dengan maksud membunuh semua mikroorganisme patogen, membunuh sebagian besar mikroorganisme pembusuk dan menginaktifkan enzim

31 Untuk membunuh bakteri patogen, yaitu bakteri yang berbahaya karena dapat menimbulkan penyakit pada manusia. Bakteri pada susu yang bersifat patogen misalnya Mycobacterium tuberculosis dan Coxiella bunetti dan mengurangi populasi bakteri. Untuk memperpanjang daya simpan bahan atau produk Dapat menimbulkan citarasa yang lebih baik pada produk Pada susu proses ini dapat menginaktifkan enzim fosfatase dan katalase yaitu enzim yang membuat susu cepat rusak.

32 Ada 2 cara pasteurisasi, yaitu: a. Pasteurisasi lama (Low Temperature Long Time - LTLT). Pemanasan susu dilakukan pada temperatur yang tidak begitu tinggi dengan waktu yang relatif lama (pada temperatur 65 o C selama 15 menit). b. Pasteurisasi singkat (High Temperature Short Time - HTST). Pemanasan susu dilakukan pada temperatur tinggi dengan waktu yang relatif singkat (pada temperatur 72 o C selama 15 detik).

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