Introduction

Otak-otak is made mainly from fish paste and it can be found throughout Malaysia, Singapore and Indonesia. Muar which is located southern part of Malaysia (Johor) is famous with otak-otak. The soft and squashy appearance of the otak-otak is quite similar to the brain. Thus, the dishes are called otak-otak where “otak” means brain in Malay. The otak-otak is usually wrapped with banana leaves and with toothpicks at the end of the leaves to prevent the otak-otak flow out.

It is usually cooked in 2 ways: grilling and steaming. The grilled otak-otak gives a reddish-orange, drier and with a more distinct smoky fish aroma. Whereas, the steamed otak-otak gives a pale reddish-orange fish cake and it is softer and tender to eat. These 2 ways of cooking are depends on individual’s preference.

Ingredient

Grilled otak-otak wrapped in banana leaf dipped with peanut sauce(5 servings):

-200 g Mackerel fish flesh
-1 egg
-50 ml coconut milk
-2 teaspoon salt
-50 g flour
-10 g shallot
-5 cloves garlic
-½ teaspoon pepper
-25 ml chicken stock
-50 g peanut
-5 g chili
-150 ml water
-20 g sugar
-½ teaspoon vinegar
-2 teaspoon oil

Methods

1. Firstly, ground the shallot, 3 cloves of garlic and pepper.
2. Then, it mixes well with Mackerel fish flesh, egg, coconut milk, 1 teaspoon of salt, flour and chicken stock.
3. Wrap the mixture in banana leaves. After that, soften it with steaming then grilled.
4. Fry chili, 2 cloves of garlic and water to make sauce. Then, ground and mix with sugar, vinegar, oil and 1 teaspoon of salt.
5. Serve the otak-otak with the peanut sauce.

(Koeniel, 2009)

Nutritional values:

(Koeniel, 2009)

Graph1: Calorie Breakdown of Otak-otak per Serving

Graph2: Daily Value of Nutrient

Metabolism involved:

Carbohydrates Metabolism

Glucose in the body undergoes one of three metabolic fates:

1. It is catabolised to produce energy in the form of ATP. This occurs in all peripheral tissues, particularly in brain, muscle and kidney.

Glycolysis is the oxidation of glucose into pyruvate and lactate by Emden-Meyerhof Pathway. This pathway cleaves the six carbon glucose molecule (C6H12O6) into two molecules of the three carbon compound pyruvate (C3H3O3-) and nett production of two molecules of ATP per glucose molecule

Diagram 1: Glycolysis by Emden-Meyerhof Pathway
Diagram sources: http://faculty.ksu.edu.sa/70917/Pictures%20Library/glycolysis%20pathway.gif

Aerobic metabolism of glucose transport pyruvate inside mitochondria and oxides to acetyl-Co-A. Then, Kreb cycle oxides acetyl-CoA to CO2. These reactions are coupled to a process known as the electron transport chain which has the role of harnessing chemical bond energy from a series of oxidation-reduction reactions to the synthesis of ATP and simultaneously re-oxidising NADH to NAD. Meanwhile, anaerobic glycolysis converts pyruvate into lactate. This reaction is important in the muscle when energy demands exceed oxygen supply.

Diagram 2: Aerobic glycolysis vs. Anaerobic glycolysis

2. It is stored as glycogen. This storage occurs in liver and muscle.
Glycogenesis is the process of synthesis of glycogen from glucose. It requires energy supplied by ATP and UTP.

3. It is converted to fatty acids. Once converted to fatty acids, these are stored in adipose tissue as triglycerides.
Sustained high glucose intake in the diet leads to increased fat synthesis. It is converted to a fuel storage form which has an unlimited capacity such as triglycerides stored in adipose tissue. (Adams, 2000).

Protein Metabolism

Digestion breaks protein down to amino acids. If amino acids are in excess of the body's biological requirements, they are metabolized to glycogen or fat and then used for energy metabolism. If amino acids are to be used for energy, their carbon skeletons are converted to acetyl-CoA which enters the Krebs cycle for oxidation, producing ATP. The final products of protein catabolism include carbon dioxide, water, ATP, urea, and ammonia.

Transamination converts amino acids to L-glutamate which undergoes oxidative deamination to form ammonia, used for the synthesis of urea. Urea is transferred through the blood to the kidneys and excreted in the urine.

The glucose-alanine cycle is the main pathway by which amino groups from muscle amino acids are transported to the liver for conversion to glucose. Body proteins are broken down when dietary supply of energy is inadequate during illness or prolonged starvation (Patel, 2008).

Lipid metabolism

Fatty acids come from the diet, included adipocytes (fat cells), carbohydrate, and some amino acids. After digestion, most of the fats are carried in the blood as chylomicrons. The main pathways of lipid metabolism are lipolysis, beta-oxidation, ketosis, and lipogenesis.

Lipolysis and beta-oxidation occurs in the mitochondria. It is a cyclical process in which two carbons are removed from the fatty acid per cycle in the form of acetyl CoA which proceeds through the Krebs cycle to produce ATP, CO₂, and water.

Ketosis occurs when the rate of formation of ketones by the liver is greater than the ability of tissues to oxidize them. It occurs during prolonged starvation and when large amounts of fat are eaten in the absence of carbohydrate.

Lipogenesis occurs in the cytosol. The main sites of triglyceride synthesis are the liver, adipose tissue and intestinal mucosa. The fatty acids are derived from the hydrolysis of fats or from the synthesis of acetyl-CoA through the oxidation of fats, glucose and some amino acids. Lipogenesis from acetyl CoA also occurs in steps of two carbon atoms. NADPH produced by the pentose-phosphate shunt is required for this process. Phospholipids form the interior and exterior cell membranes and are essential for cell regulatory signals (Patel, 2008).

Cholesterol metabolism

Cholesterol is an extremely important biological molecule that has roles in membrane structure as well as being a precursor for the synthesis of the steroid hormone and bile acids. Both dietary cholesterol and that synthesized de novo are transported through the circulation in lipoprotein particles. The same is true of cholesteryl esters, the form in which cholesterol is stored in cells. The synthesis and utilization of cholesterol must be tightly regulated in order to prevent over-accumulation and abnormal deposition within the body (King 2009).

Sodium metabolism

The Na+ pump is a form of active transport. ATP pumps ions uphill against their electrochemical gradients through the membrane by a special protein enzyme known as sodium potassium ATPase that serves as a pumping mechanism. Such processes must occur within living cells for optimal distribution of cellular chemicals. Sodium ions normally stay in the cell, due to its low levels of concentration. As such, sodium outside the cell naturally wants to continue to diffuse into the plasma membrane (Venom, n.d.).

Physiological Benefit of Otak-otak

Protein present in the fish helps defend body against diseases, source of energy, building material for enzymes and hormone in our body. The otak-otak is high in iron where eggs and fish (ingredient of otak-otak) are common source of iron. Physiological functions of iron in our body are hemoglobin formation; act as a cofactor for enzymes making amino acids, collagen, hormones, and transportation of oxygen in red blood cell to every parts of the body. Calcium present in otak-otak helps bone and tooth formation in our body. It also aids in blood clotting mechanism, muscle contraction and relaxation and lastly nerve transmission.

Vitamin A from egg promotes vision and also supports reproductive growth. Vitamin C acts as cofactor in collagen synthesis, help in iron absorption, amino acid metabolism and also as an antioxidant.

Some of the ingredients in the otak-otak are rich in phytochemicals. For examples, hot peppers contain capsaicin modulates blood clotting which may reduce the risk of clot in heart. Oragnosulfur compounds present in garlic may lower blood cholesterol and protect against stomach (Whitney & Rolfes, 2008, p.470-47).

Improvement on Otak-otak:

• Reduce salt content in the otak-otak. High intake of salt will produce physiological changes in the kidney, which contribute to high blood pressure. This can lead to heart disease and stroke. It is recommended that after consuming otak-otak, we should drink more water to balance of sodium and water in the body.
  


• For the salmon fish lover, the fish use for making otak-otak can be replaced with salmon fish. It is proven that salmon fish is rich in Omega-3 as it contributes protective effects against coronary heart disease by lowering the bad cholesterol (LDL), prevent blood clot, protect against irregular heartbeats (ASMI, 2009). In addition, it is suggested that use omega 3 rich egg in the otak-otak instead of normal egg, as it is more nutritious.

• The oil used for making otak-otak should be monounsaturated or polyunsaturated oil such as olive oil, sunflower oil, soybean oil, etc. Monounsaturated fats such as olive oil has phytochemical function to help protect against heart disease. Replacing saturated fats with the polyunsaturated fats of other vegetable oils help lower the blood cholesterol. Palm oil is not recommended as it is high in saturated fat. It is better to consume the otak-otak immediately as unsaturated oil is not very stable and easily be oxidized (Whitney & Rolfes, 2008, p.158).
  


• Recent research has found that grilled meat produces heterocyclic amines (HCAs) which are formed when the meat is cooked under high heat and long cooking time. Creatine (a specific amino acid found in muscle) and sugars contain naturally in meats will combine and form HCA, a cancer-causing compounds. Although grilled otak-otak in banana leaf gives a nice taste to the food, it is better to steam the otak-otak (PCRM, 2005).

• Fiber can decrease risk of intestinal inflammation, promotes bowel movement and relieves constipation. By including some vegetables such as cabbage into the otak-otak, the fibre content will increase. Besides, it is also recommended to eat along with whole grain bread to increase your fibre intake.
  

References:

1. Whitney, E. & Rolfes S.R., 2008. Understanding Nutrition. 11^th ed. USA: Thomson Wadsworth p. 158, 470-472;


2. Adams, D., 2000. Introductory Metabolism Module [Online]. University of South Australia, Australia. Available from: <http://www.unisanet.unisa.edu.au/08366/h&p2carb.htm > [Assessed 16 February 2009]


3. ASMI, 2009. Wild Salmon Health & Diet Information [Online]. Available from: [Accessed 21 February 2009]


4. Koeniel, 2009. Otak-otak Recipe [Online]. Available from: <http://caloriecount.about.com/otak-recipe-r15836 > [Assessed 10 February 2009]


5. Michael W. King, Ph.D, 2009. Introduction to Cholesterol Metabolism [Online]. IU School of Medicine, Indiana University, U.S. Available from: <http://themedicalbiochemistrypage.org/cholesterol.html#introduction > [Assessed 16 February 2009]


6. Patel, G., 2008. Metabolism [Online]. Available from: <http://www.faqs.org/nutrition/Met-Obe/Metabolism.html> [Assessed 16 February 2009]


7. PCRM, 2005. The Five Worst Food to Gill [Online]. Available from: <http://www.pcrm.org/health/reports/worst_grill.html> (Physicians Committee for Responsible Medicine) [Accessed 21 February 2009]


8. Venom, n.d. Sodium- A Comprehensive Analysis [Online]. Available from: <http://www.abcbodybuilding.com/magazine03/sodium.htm > [Assessed 16 February 2009]