Contact: University of the Philippines-Office of the Vice Chancellor for Research and Development Institution: University of the Philippines Diliman
A study shows that the traditional fish/shrimp paste condiment, or bagoong, of the Philippines contains the beneficial omega-3 fatty acids. In its analysis, it was found that among the samples of bagoong, shrimp paste has the highest omega-3 content.
The famous Bagoong, also referred to as fish or shrimp paste, is one of the traditional flavor extenders used in the Philippines. It has several variations according to the type of fish used, color, and taste. Bagoong is prepared by fermenting the fish or shrimp in high concentrations of salt for several months. Consumed either as a complement of green mangoes or as a seasoning to some Filipino delicacies such as pinakbet, little is known about the nutritional content of these condiments since they are usually sold without labels in local markets.
Fish and other marine food resources are known to be good sources of long-chain ω-3 (omega-3) polyunsaturated fatty acids. One in particular is the all-cis-4,7,10,13,16,19-docosahexaenoic acid (DHA), a variant of the long-chain ω-3 fatty acid, which is essential to the neural development of growing infants especially in brain and retina development. Sufficient amount of DHA is required for an active brain function throughout a human’s lifespan. DHA has also been found to lower blood pressure and chances of occurrence of heart disease and mental illness. Though high levels of DHA are produced during pregnancy and during the first two months of infancy, the normal human body condition can only manufacture these fatty acids metabolically in small amounts. DHA must then be acquired from the diet or produced through the consumption of ω-3 precursors such as α-linolenic acid found in seeds and nuts.
The composition of bagoong suggests the possibility that the said condiment may be a dietary resource of long-chain ω-3 polyunsaturated fatty acids. In the study “Polyunsaturated fatty acid contents of some traditional fish and shrimp paste condiments of the Philippines,” scientists Nemesio Montaño, Grace Gavino and Victor C. Gavino assess the fatty acid composition of various types of fish and shrimp paste in reaction to the brine solution used for fermentation.
Montaño’s team gathered samples of six types of fish and shrimp paste condiments from a public market in Bolinao, Pangasinan located at Western Luzon of the Philippines. The vendors of these products were interviewed regarding their preparation process of bagoong. The general preparation of bagoong according to them is that fish or shrimp fry are deposited alternately in layers with salt in ratios of three to four parts of salt to one part of fish or shrimp fry. The mixture is then incubated at ambient temperature in a specific period of time depending on the fish type used. The fish types used in the collected samples were verified through visual investigation. The samples were found to be made from Dalagang bukid (Fusiliers, Caesio spp.), Dilis (Silver sprat, Spratelloides gracillis), Padas-1 (Fuscescens rabbitfish, Siganus fuscescens), Padas-2 (Forktail rabbitfish, Siganus argenteus), Terong (Fusiliers, Pterocaesio spp.) and Alamang (Shrimp fry, Acetes spp.). Samples were analyzed fresh or freeze-dried. The composition of fresh untreated alamang was also compared with the composition of salt-treated alamang.
Fatty acid composition, salt content, moisture and water activity of the fish/shrimp paste samples were measured to examine if the salinity of the paste condiments and the oxidation process significantly affect the fatty acid content of the fish and shrimp fry. Ash and fat content were also studied to look further into the composition of bagoong. The salt content of the samples was determined using the Mohr Method  while moisture was calculated from the sample’s weight loss when dried. Water activity was determined by equilibration with the salt solution. The dried samples were then reduced to ashes to measure the ash content. Fat content was measured by Soxhlet extraction  of the freeze-dried samples and the fatty acid composition was determined using an adaptation of a direct methylation procedure on the sample followed by gas chromatography.
Findings show that the salt content of the bagoong samples does not tally with the ratio of salt to fish/shrimp fry given by the vendors. Salinity was found to range from 19 to 24%, which greatly differs from the 60 to 80% accounted from the vendors’ statement. The alamang condiment was also found to contain the highest level of DHA ω-3 polyunsaturated fatty acids among the samples followed by Padas-1. The Dalagang bukid paste condiment, on the other hand, has the lowest. According to Dr. Montaño, this may be explained by the phytoplanktons and bacteria the shrimp fry consume which could have produced the high levels of long-chain polyunsaturated fatty acids.
1. Thomson Healthcare, PDRhealth. “Docahexaenoic Acid (DHA).” <http://www.pdrhealth.com/drug_info/nmdrugprofiles/nutsupdrugs/doc_0093.shtml>
2. DHA/EPA Omega-3 Institute. “DHA for Optimal Brain and Visual Functioning.“ <http://www.dhaomega3.org/Introduction/brain.htm>
3. The Kushi Institute of Europe, Encyclopedia. “Fats.” <http://www.macrobiotics.nl/encyclopedia/encyclopedia_f.html>
4. University of Canterbury, Christchurch New Zealand. “Determination of Chloride Ion Concentration by Titration (Mohr’s Method).”
 Mohr Method is the process of determining chlorides in bagoong sample using titration with silver nitrate and indicator potassium chromate. The pH level of the sample to be tested should be between 6.5 to 10 for more accurate readings.
 Soxhlet Extraction is the process of extracting fat from the freeze-dried bagoong sample using low-boiling petroleum ether as solvent.
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