If you get a chance to visit the food galore Penang, regardless you are a tourist or local tourism, you will never wanted to miss out one of the most tempting food in the island - Assam Laksa. The reason why Penang Assam Laksa could gain its popularity is due to the spicy and sour sensation of the fish broth. Tamarind or more commonly known as the assam is used generously in the soup base. Peeled tamarind, Assam keping is added to enhace the tartness of the soup. Another secret ingredient to make delicious assam laksa is the Polygonum leaf or daun kesom/daun laksa. Ginger flower (bunga kantan) gives aromatic flavour while belacan and prawn paste boost the flavour of the the broth. Wolf herring or Spanish mackerel is the type of fish which suits the soup best. Assam laksa will never be perfect without thick rice noodles. Served with crispy freshly sliced cucumber, onions, and pineapple and refresing mint leaves, Penang Assam Laksa will definitely satisfies your taste buds!
Table 1: Analysis for Penang Assam Laksa (Health Promotion Board, 2009)
*Per serving of 569.4 g
So, theoritically, Wey Lim's body is obtaining protein, fats, dietary fiber, carbohydrate, cholesterol, sodium, calcium and iron in significant amounts.
Table 2: Energy requirements for by life stages (MOH, 2005)
If Wey Lim practises normal active lifestyles (with Physical Activity Level = 1.75), the energy requirement recommended for Wey Lim is 2440 kcal/day.
The Recommended Nutrient Intake (RNI) for some macronutrients are:
- Protein: 62 g/day
- Fats: 54 - 82 g/day
- Dietary fiber: 38 g/day
(Source: Ministry of Health, 2005)
Most nutrients provided by a bowl of Assam Laksa fall within the acceptable range of the RNI recommended by Malaysia's Ministry of Health except sodium.
Physiological benefits:
First of all, let's pick out some typical ingredients serve in the Assam Laksa.
- Rice noodles
- Fish - wolf herring or Spanish mackerel
- Fresh vegetables and fruit
- Spices
Now, we are going to explore each's benefits:
Rice noodles: Obviously, rice noodles play the role as the main energy provider as they are made of rice.
Fish: A good source of first class protein, providing essentials amino acids to Wey Lim's body.
Fresh vegetables and fruit: Cucumber and leafy vegetables slices contain vital vitamins and minerals such as vitamin C, potassium, magnesium and iron. Whereas fresh pineapple is a known source of vitamins such as vitamin A and vitamin C (Health Promotion Board, 2009)and proteolytic enzyme, Bromelain (American Academy of Anti - Aging Medicine, 2005). Besides, these foods is a source of dietary fiber.
Herbs and Spices: Loads of herbs and spices are used in preparing the soup as well as freshly served. Ginger bud and garlic are high in anti - oxidant, which indirectly having anti - ageing effects (Imilia and Nordin, n.d.). Tamarind has been found to delay the progression of fluorosis by enhancing excretion of fluoride (Healthline, n.d.). In addition, turmeric root is a popular relief for inflammation, swelling and stomach problems (supplementnews.org, 2007).
***Please take note that eating these foods in small portions do not benefits our body significantly.Disadvantages:
Based on Health Promotion Board (2009), Assam Laksa contains high amount of sodium, 2287 mg in each serving of 569.4 g whereas the Upper Level (UL) for sodium for an adult is 2300mg/ day(Whitney and Rolfes, 2008). The high amount of sodium is contributed by shallots, prawn paste and belacan. High intake of sodium in a long term is usually associated with cardiovascular diseases and kidney problems.
Apart from that, preparing the soup with high amount of tamarind pulls down the pH of the soup making it very sour in taste and may not be suitable for consumption for certain group of individuals such as those with digestion problems.
Metabolisms involved:
Carbohydrate
Once rice noodles enter Wey Lim's mouth, salivary amylases convert complex carbohydrate - starch into small polysaccharides and maltose (Whitney and Rolfes, 2008). In his stomach, the acidic condition inactivates its digestion process (Whitney and Rolfes, 2008). When the food reaches small intestine and pancrease, starch is cleaved to smaller polysaccharides and maltose by pancreatic enzymes (Whitney and Rolfes, 2008). Small intestinal disaccharidase converts the disaccharides to monosaccharides (Whitney and Rolfes, 2008). Finally, the final product is adsorbed into the intestinal cells (Whitney and Rolfes, 2008).
Most simple sugars absorption occurs in the small intestine, whereby glucose and galactose are actively transported into the cell lining in the small intestine and fructose is through facilitated diffusion (Whitney and Rolfes, 2008). However, there is a small amount of glucose which enters the bloodstream through the lining of his mouth (Whitney and Rolfes, 2008).
As blood from the intestine reaches the liver, fructose and galactose are transformed into glucose and other compounds through a series of biochemical processes (Whitney and Rolfes, 2008). First of all, glucose functions as the the raw material for energy production especially his brain which relies solely on glucose as the source of energy (Whitney and Rolfes, 2008). Glucose undergoes oxidation to yield energy and carbon dioxide and water as the by-products (Whitney and Rolfes, 2008). After a bowl of Assam Laksa, his blood glucose shoots up, and liver cells automatically respond to this alteration by arranging and joining those excessive glucose into long, branching chains of glycogen via condensation (Whitney and Rolfes, 2008). Throughout his day, when the blood glucose started to drops, the liver cells replenish the sugar reservoir in the bloodstream by freeing simple molecules of glucose from the glycogen (Whitney and Rolfes, 2008). If Wey Lim continues to try out other delicious foods in Penang, excessive glycogen storage contributed by the foods will be stored in his liver (Whitney and Rolfes, 2008). As his liver will holds the high amount of glycogen for not more than a-day-period, the liver will store them in a more permanent means - fat (Whitney and Rolfes, 2008).
Lipids
Lingual lipase is secreted by Wey Lim's base of the tongue and plays a minor role in fat digestion (Whitney and Rolfes, 2008). However, this acid - stable enzyme acts as the key start for lipid digestion in his stomach (Whitney and Rolfes, 2008). It breaks down tryglycerides into diglycerides and free fatty acids (Whitney and Rolfes, 2008). The churning action in the stomach cuts down the size of the fat droplets, increasing the chances of the droplets being hydrolyzed by gastric lipase (Whitney and Rolfes, 2008). Nonetheless, only a small amount of fats is being digested (Whitney and Rolfes, 2008). Bile from gallbladder flows into the small intestine through bile duct to emulsify fat (Whitney and Rolfes, 2008). Pancreatic and intestinal lipases convert emulsified fat into simpler forms which can be easily absorbed by Wey Lim's body; the monoglycerides, glycerol and fatty acids (Whitney and Rolfes, 2008). Some fat and cholesterol are excreted out of the his body together with feces (Whitney and Rolfes, 2008).
Absorption takes part after a series of break down processes. Small fat molecules like glycerols, and short- and medium-chain fatty acids pass through the intestinal lining and enter the bloodstream (Whitney and Rolfes, 2008). Bile packs larger monoglycerides and fatty acids into spherical complexes micelles to improve the solubility of the molecules in hydrophilic environment and thus enable transportation into the intestinal cells (Whitney and Rolfes, 2008). When the fat molecules are assembled in the intestinal cells, the newly formed triglycerides and other lipids are incorporated with chylomicrons - the transport proteins (Whitney and Rolfes, 2008). From the intestinal cells, chylomicrons enters the lymphatic system, to the thoracic duct where they are finally released into the bloodstream and distributed throughout his body (Whitney and Rolfes, 2008).
Fat yields twice the energy of carbohydrate and protein (Whitney and Rolfes, 2008). For this reason, fat is an excellent storage form of energy for Wey Lim's body (Whitney and Rolfes, 2008). Specialized fat - storing tissue, the adipose tissue offers unlimited storage capacity (Whitney and Rolfes, 2008). When his body desires to store fat, the fat is chopped into several relatively smaller parts, absorbs the parts and then restructured into its original molecules again (Whitney and Rolfes, 2008).
Protein
Wey Lim's chewing actions crush the protein - rich food into smaller parts (Whitney and Rolfes, 2008). Chemical digestion of protein starts in his stomach where gastric juice consisting of hydrochloric acid (HCl) and pepsin is released (Whitney and Rolfes, 2008). HCl denatures protein and prepares an acidic environment for pepsin to work efficiently (Whitney and Rolfes, 2008). Protein is broken down into smaller polypeptides (Whitney and Rolfes, 2008). Digestion process continues in the small intestine where pancreatic and small intestinal proteases convert polypeptides into tripeptides, dipeptides and amino acids (Whitney and Rolfes, 2008). Intestinal tripeptidases and dipeptidases further break down peptides into amino acids which is then being absorbed into the intestinal cells (Whitney and Rolfes, 2008).
There are several carriers which transport amino acids into the intestinal cells (Whitney and Rolfes, 2008). Amino acids in the cells ended up in two fates; either being utilized by the intestinal cells to produce energy and needed compounds or being released into the surrounding fluid, enter the capillaries and heading to the liver (Whitney and Rolfes, 2008).
In every cell, amino acids are continuously being synthesized and broken down - the protein turnover process and form an "amino acid pool" when mixed with amino acids obtained from the fish in the Assam Laksa (Whitney and Rolfes, 2008). These amino acids become the ingredients to make proteins, nitrogen - containing compounds, other compounds such as neurotransmitters and melanine and energy when nitrogens in the molecules are removed (Whitney and Rolfes, 2008). Protein turnover works together with nitrogen balance (Whitney and Rolfes, 2008). In Wey Lim's body, protein synthesis balances with degradation and protein intake from the Laksa and other foods balances with nitrogen excretion in all ways (Whitney and Rolfes, 2008). If Wey Lim is consuming a lot of protein rich foods besides Laksa, and carbohydrate supply is sufficient, excessive amino acids are deaminated and turned into fat (Whitney and Rolfes, 2008).
Possible modifications:
Generally, Assam Laksa can be considered a healthy food given that some modifications are made to adjust some nutrient values to normal level and rising its nutritional values.
Certain amount of tamarind can be replaced by apple cider vinegar to give the acidity and tartness of the soup. Dr. D. C. Jarvis (1950) commented in his book titled "Folk Medicine: A New England almanac of natural health care from a noted Vermont country doctor" that apple cider vinegar is able restore alkaline acid balance in human's body. Besides, high intake of sodium might increase potassium demand (UMMC, 2008). This potassium-rich-vinegar is essential to satisfy the need.
Better options of salt such as Sal Kal (low sodium salt) and sea salt are recommended instead of table salt as they are lower in sodium content but rich in other minerals while saltier in taste with lesser application.
Prepared by: Ooi Hooi Leng & Goh Ee Vian
References:
American Academy of Anti - Aging Medicine, 2005. Bormelain (Pineapple enzyme) [Online]. Available from: http://www.worldhealth.net/news/bromelain_pineapple_enzyme [Accessed on: 21 February 2009]
Ellie Whitney and Sharon Rady Rolfes, 2008. Understanding Nutrition. Eleventh Edition. United States of America: Thomson Wadsworth, page 101 - 194.
Healthline, n.d. Tamarindus indica [Online]. Available from: http://www.healthline.com/natstandardcontent/tamarind [Accessed on: 21 February 2009]
Health Promotion Board, 2009. Energy and Nutrient Composition of Foods [Online]. Available from: http://www.hpb.gov.sg/hpb/default.asp?pg_id=1016 [Accesed on 21 February 2009]
MalaysianFood.net, 2008. Penang Laksa / Assam Laksa [Online]. Available from: http://www.malaysianfood.net/recipes/recipelaksaassam.htm [Accessed on: 20 February 2009]
Ministry of Health (MOH), 2005. 2 Energy [Online]. Available from: http://www.moh.gov.my/opencms/export/sites/default/moh/download/2_chat.pdf [Accessed on 21 February 2009]
Ministry of Health (MOH), 2005. 5 Protein [Online]. Available from: http://www.moh.gov.my/opencms/export/sites/default/moh/download/5_chat.pdf [Accessed on 21 February 2009]
Rasa Malaysia, 2008. Penang Assam Laksa Recipe (Nyonya Hot and Sour Noodles in Fish Soup) [Online]. Available from: http://www.rasamalaysia.com/2008/02/recipe-penang-assam-laksa.html [Accessed on: 20 February 2009]
