Pengolahan (pengawetan) dilakukan untuk memperpanjang umur simpan (lamanya suatu produk dapat disimpan tanpa mengalami kerusakan) produk pangan. Proses pengolahan yang akan dilakukan, tergantung pada berapa lama umur simpan produk yang diinginkan, dan berapa banyak perubahan mutu produk yang dapat diterima.
Pinsip Pengawetan Pangan ada tiga, yaitu:
- Mencegah atau memperlambat kerusakan mikrobial.
- Mencegah atau memperlambat laju proses dekomposisi (autolisis).
- Mencegah kerusakan yang disebabkan oleh faktor lingkungan termasuj serangan hama.
Berdasarkan target waktu pengawetan, dapat bersifat jangka panjang atau pendek.
Pengawetan jangka pendek dilakukan dengan beberapa cara:
Penanganan aseptis, dilakukan dengan mencegah masuknya kontaminan kimiawi dan mikroorganisme ke dalam bahan pangan, atau mencegah terjadinya kontaminasi pada tingkat pertama. Penanganan produk dilakukan untuk mencegah kerusakan pruduksi yang bisa menyebabkan terjadinya pengeringan (layu), pemecahan enzim alami dan masuknya mikroorganisme.
Penggunaan suhu rendah (kurang dari 20 derajat celcius), untuk memperlambat laju reaksi kimia, reaksi enzimatis dan pertumbuhan mikroorganisme tanpa menyebabkan kerusakan produk.
Pengeluaran sebagian air bahan, beberapa perubahan kimia seperti terjadi pada tepung, sereal, biji-bijian, minyak disebabkan oleh keberadaan air. Air dibutuhkan mikroorganisme untuk mempertahankan hidupnya. Pengeluaran sebagian kandungan air bahan melalui proses pemekatan atau pengeringan akan menurunkan laju reksi kimiawi, enzimatis maupun mikrobial.
Perlakuan panas “ringan”, (pasteurisasi dan blansir) dilakukan pada suhu dibawah 100 derajat celcius. Proses blansir akan merusak sistem enzim dan membunuh sebagian mikroorganisme. Tetapi, sebagian besar mikroorganisme tidak dapat dihancurkan oleh proses blansir. Pasteurisasi menggunakan intensitas suhu dan waktu pemanasan yang lebih besar dari pada blansir. Pasteurisasi akan menginaktifkan enzim, membunuh mikroorganisme patogen (penyebab penyakit) dan sebagian mikroorganisme pembusuk.
Mengurangai keberadaan udara, Beberapa reaksi penyebab kerusakan pangan dipicu oleh oksigen. Reaksi kimiawi seperti oksidasi lemak (tengik) yang terjadi pada minyak sayur, biji – bijian, buah- buahan, sayuran , susu, daging dan reaksi pencoklatan pada buah dan sayur dapat diperlambat dengan mengurangi kehadiran oksigen.
FOOD PRESERVATION PRICIPLES
Preservation is done to extend the life savings (the length of a product can be stored without damage) of food product. Manufacturing processes that will be done depends on how long the old store the desired product and how many changes in product quality is acceptable.
There are three food preservation principles:
Preservation is done to extend the life savings (the length of a product can be stored without damage) of food product. Manufacturing processes that will be done depends on how long the old store the desired product and how many changes in product quality is acceptable.
There are three food preservation principles:
- Preventing microbial damage.
- Prevent or slow the decomposition process (autolisis).
- Prevent damage caused by environmental factors such as pest.
Based on the target date for preservation, it may be long or short.
Short-term preservation can be done in several ways:
Aseptic handling, is done by preventing the entry of chemical contaminants and microorganisms in food, or prevent contamination at the first level. Handling products is done to prevent damage production which can cause drying (wilting), a natural enzyme solution and the entry of microorganisms.
The use of low temperatures (below 20 degrees Celsius), to slow the chemical reaction rate, enzimatis reactions and the growth of microorganisms without causing damage to the product.
Taking out some water material some chemical changes can occur in the flour, cereals, grains, oil caused by the presence of water. Microorganisms need water to sustain life. Taking out some of the water content of the material through the drying process will reduce the rate of chemical, or microbial enzimatis.
Heat treatment "light", (pasteurization and blansir) performed at a temperature below 100 degrees Celsius. Blansir process will damage the enzyme systems and kill some microorganisms. However, most microorganisms can not be destroyed by blansir process. Pasteurization uses the intensity of the heating temperature and time greater than the blansir. Pasteurization will inactivate enzyme, killing pathogenic microorganisms (disease causing) and some microorganisms decay.
Reducing air Some food reactions which cause damage triggered by oxygen. Chemical reactions like oxidation of fat (rancidity) that occurs in vegetable oils, seeds - grains, fruits, vegetables, milk, meat and brownish-reaction to fruits and vegetables can be slowed by reducing the presence of oxygen.
( WM )
Short-term preservation can be done in several ways:
Aseptic handling, is done by preventing the entry of chemical contaminants and microorganisms in food, or prevent contamination at the first level. Handling products is done to prevent damage production which can cause drying (wilting), a natural enzyme solution and the entry of microorganisms.
The use of low temperatures (below 20 degrees Celsius), to slow the chemical reaction rate, enzimatis reactions and the growth of microorganisms without causing damage to the product.
Taking out some water material some chemical changes can occur in the flour, cereals, grains, oil caused by the presence of water. Microorganisms need water to sustain life. Taking out some of the water content of the material through the drying process will reduce the rate of chemical, or microbial enzimatis.
Heat treatment "light", (pasteurization and blansir) performed at a temperature below 100 degrees Celsius. Blansir process will damage the enzyme systems and kill some microorganisms. However, most microorganisms can not be destroyed by blansir process. Pasteurization uses the intensity of the heating temperature and time greater than the blansir. Pasteurization will inactivate enzyme, killing pathogenic microorganisms (disease causing) and some microorganisms decay.
Reducing air Some food reactions which cause damage triggered by oxygen. Chemical reactions like oxidation of fat (rancidity) that occurs in vegetable oils, seeds - grains, fruits, vegetables, milk, meat and brownish-reaction to fruits and vegetables can be slowed by reducing the presence of oxygen.
( WM )
