TOXIC COMPOUND IN FOOD PROCESSING

The main purpose food processing is to improve the quality of food, so worthy to be eaten. However, some processing would encourage a new compound that is toksik dangerous for people. Many of the new compound form due to interactions between food components and endogenus or eksogenus or semyawa-turunannya compound, or between the compound-compound with the component from the outside, such as oxygen. Chemical degradation that occurs due to heat exposure, light, enzyme, or the other can also produce toxic compound. In the summary of some of this toxic compound that during processing will be discussed.


CHEMICAL CHANGES AND SOME VALUES IN FOOD RESULTING PROCESS

1.Carbohydrate
Monosakarida quite stable in the pH range 3 - 7. However, outside the pH, and also depends on other conditions, can be extensive changes occur. Enolisasi followed by elimination of water molecules is the dominant reaction that occurred in the acid atmosphere. Basa on the atmosphere, can also occur enolisasi, fragmentation can occur even sugar molecule followed by a secondary reaction. This reaction will be faster with the heating and with the high temperature heating. Basa on the condition, especially when accompanied with heating, simple sugar molecule to fragmentation (break carbon-carbon bonds) through the reaction retroaldol produce various karbonil a reactive compound. This reaction results in addition to the compound compound volatil also play a role in flavor compound brown. In terms of nutrition reactions that occur on the sugar, especially during the heating will reduce the availability of sugar so that the calorie value of food to be decreased. In addition, although still controversial, brown compound, which is made of a polymer, is feared to give the impact of health
the less good. Unlike monosakarida, heating polisakarida such as starch, especially in the media a lot of water is beneficial because the starch molecules into akan terhidrolisa-a small molecule, oligo-, di-or monosakarida so that the starch terhidrolisa be more easily digested by the body.

2. Protein
Basically the Maillard reaction consists of the reactions of a very complex interconnected with each other form a network process. In the
Basically, Maillard reaction is divided into three phases namely: initial, intermediet
and end. All amino acids can participate in the Maillard reaction because they have a free amino group. However, most amino acids in food is in the form of a bound on the chain and only peptida alpha amino group or terminal amino group of the side chain that can react with the cluster karbonil (karbonil generally cluster in the sugar pereduksi). However, it is clear Maillard reaction can affect the biological availability of protein (bioavailability) of protein as amino acid residues in the divider peptida residues such as ALA, arg and his akan react with sugar pereduksi form Amadori products. Have known that from the Amadori product lisin either lisin free and the bound on peptida turns 70 persennya not absorbed by the baby so it does not bioavailable.

Maillard reaction can also produce toksik compound, compound is a compound including the group amin heterosiklik known by the name imodazaquinolin (IQ) and imidazaquinoxalin (IQx). Piridin or pirazin results Maillard reaction reacts with aldehida and kreatin to form IQ and IQx. IQ and IQx compound has been identified on the roast beef, grilled chicken, fried beef and grilled sardine. Measure this compound decreases with decreasing heating temperature.
Meat and fish are heated (cooked with the heating) can contain the value heterosiklik amin ppb (part per billion). However, the new measure on the ppm (part per million) per kg body weight amin heterosiklik able to trigger tumor terbentuknya in rodents and monkeys, a rate far higher degree of aminheterosiklik of the food.

3.Lipid
Reactions that occur in the general lipid during processing include hydrolysis, oxidation and pirolisis. Lipid oxidation is usually through the formation of free radical process that consists of three basic processes, namely: initiation, propagasi, and termination can Hidroperoksida in various positions where the double bond are, for example in the acid oleat there are 4 hidroperoksida be the top position of the peroxide can be in a position 8, 9, 10 or 11. Hidroperoksida saturated fatty acid not made because the oxidation is very stable and not easy to rupture and form a variety of flavor compound and also nonvolatil product. Decomposition hidroperoksida involving termination of cluster-OOH alkosi so radical form and radical hidroksi. Alkoksi radical termination and the beta chain in the form so that the CC aldehid and radical alkil or vinil.Oksidasi lipid addition can decrease the amount of lipid that can be digested and is available as a source of energy can also produce compound-compound radical. Compound-radical compound in food can be merged into the body and can trigger terbentuknya radical compound in the body. Compound radicals in the body to be a role in determining the process penuaan (aging), aterosklerosis and the occurrence of coronary heart disease (CHD, coronary heart disease).

SOME TOXIC COMPOUND

1. Heterocyclic Aromatic Amines (Haas)
Haas produced from protein-rich foods processed in the normal temperature of concoction. Nagao et al (1977) is a researcher who first reported the existence of compound mutagenik against Salmonella sp / mikrosom mammals in kondensat smoke extract and burn on the meat and fish are grilled. Based on the results of observation will be further testing of the product pirolisis (> 300oC) of various protein, carbohydrate, nukleat acid, and fat using Salmonella sp. The results show that pirolisat a mutagen only come from protein. Two types of mutagen, the TRP-P-1 and TRP-P-2 has been diisolasi in the form of pure pirolisis D, L-triptopan. This compound is a compound that was first identified as a compound from the Haas pirolisis amino acid, protein and protein-rich food

Haas used in most research mutagen is grouped into two categories based on prekusor temperature and its establishment. Group 2-aminoimidazole (aminoimidaoazarens) form in the moderate temperature (optimum temperature of 190o-200oC), suspected to originate from the Maillard reaction products (pyridines and Pyrazines) and kreatinin. Example of this compound include IQ, MeIQ, MeIQx, 4.8-DiMeIQx, 7.8-DiMeIQx, and PhIP. Compound-compound is further classified into groups quinolines, quinoxalines, and pyridines. The second group, the group of 2-aminopyridine form at a temperature above 300oC from pirolisat protein. Compound of this group include a C ,  Me C, TRP-P-1, TRP-P-2, GLU-P-1 and LYS-P-2.

2. Premelanoidins from the Maillard Reaction

Various studies have been conducted indicate that the effect toksik from premelanoidin. Frange and Adrian (1973) found a decrease in power and Retention dissolved nitrogen in the diet of the premelanoidin. As a result, protein efficiency ratio (PER) and biological value (BV) is also decreased. About 35% nitrogen premelanoidin bated in the network. However, this data does not mean that the nitrogen premelanoidin have metabolik a useful function, because the growth rate decreased drastically experimental animals up to 20% -40%. The same researchers also found that hindered the work premelanoidin enzyme digestion.

Based on research using the spray-dried and roller-dried milk, premelanoidin also suspected to be hepatotoksik. Animal experiments that the treatment given the two types of susu in the death of each reach 40% and 60% due nekrosis heart. Maillar reaction products also cause certain allergic reactions. For example, alergenisitas solution laktoglobulin-laktosa tested reaktivitasnya on the skin shows an improvement from 1000 into 100  g / mg due to heating at a temperature of 50oC (pH 7) for 48 to 78 hours. Maillard reaction products also indicate the nature mutagenik and karsinogenik on some test toksisitas short term. N-nitroso compound that has been well recognized as karsinogen can during nitrosasi (nitrosation) Maillar specific reaction products, especially Amadori compound.


3. Hydrocarbons polisiklik aromatis (Polycyclic Aromatic Hydrocarbons = PAHs)

PAHs form of combustion is not perfect organic materials. There are two main source of PAHs for humans. Most important source is the air that terpolusi used food crops in the cereal, vegetables, fruits and nuts that are a source of dihasilkannya human PAHs. Second important source of food is in the process penyangraian, evaporation, and toaster. In the food in the process of formation of PAHs is significant only when using high temperatures. At temperatures below 400o C, only a few PAHs are formed, and the amount will increase if shunya be linear up to 1000o C. Benzo [a] pyrene has been known as the active compound found in the charred materials. Karsinogen other components that also have been identified is dibenzo [a, h] anthracene, dibenzo [a, h] pyrene, dibenzo [a, i] pyrene, and benzo [b] fluroanthene. Benzo [a] pyrene is a component of most karsinogen, so much attention.

The intensive terbentuknya cause PAH. On the food that is cooked, PAHs form pirolisis of fat at a temperature above 400oC. This can occur if food or fat is exposed to charcoal or a very hot surface. Only a few techniques concoction that can cause the formation of PAHs. Establishment mechanism based on the alleged pirolisis some food components can cause terbentunya this compound. However, in most cases, the formation of the compound than fat does not happen

Toaster meat or fish over a fire caused contamination PAHs through different ways. First, the high temperature causes the formation of PHAs endogenus on the surface of the food. Second, PAHs also form from the combustion of fuel used for the toaster. Third and most importantly, the PAHs form of fat that will surface over the heat source. PAHs that pirolisis from fat spreads into the atmosphere and some live on the surface of the meat.

4. Lysinoalanine

Use alkai treatment on the process of isolat and penngolahan protein and vegetable protein for animal food production has been increasing. Alkali conditions, as has been mentioned in the beginning, can trigger the occurrence of reaction Maillaard resulting residue lisin protein can not be used. This reaction also causes other changes that are not desired, such as a decrease in power dissolved, rasemisasi and destruksi some amino acids. The process also can produce alkali derivat amino acid that is toksik in humans. Derivat example amino acid during the process that includes alkali lysinoalanine (LAL), ornithoalanine (OAL), and lanthionine.

LAL attention because this compound is suspected bersifar toksik in the kidney (neprotoksik). LAL dehidroalanin form by condensation of the epsilon amino group lisin. LAL is not the only compound that is neprotoksik that the alkali treatment. Ornithoalanine, fructoselysine, and D-serine to give the same effect with LAL in animal experiments. LAL Toksisitas and amino acid derivat that during alkali treatment of vegetable protein in humans has not been diekstrapolasi mainly because of the effects toksik not observed in animal experiments than the mouse. In addition, on the condition that only a few normal LAL that, so do not be neprotoksik. However, the formation of LAL during alkali treatment of the lower protein quality gizinya.

REFERENCES
Desphande, S.S. 2002. Toxicants resulting From Food Processing. In Handbook of Food Toxicology. Marcel Dekker, Inc. New York. Pp 285-303.

Setiyani, Sri. Processing effects of toxic compound. 2009. Lecture material. THP UNILA.

Apriantono, Anton. 2002. Influence of Processing Cost of Food Safety and Nutrition. presented at the Seminar Online Kharisma to-2. Jakarta