Fish is classified harmonizing to origin such as saltwater fish, shellfish, oily and white fish and fresh water fish. Fish is a rich beginning of protein and it contains other foods such as indispensable fatty acids, fat soluble vitamins and Ca ( Barnett, 1998 ) . In fish, it contains fat soluble vitamin such as vitamin A, D and a figure of H2O soluble vitamin B group. Vitamin A and D are largely found in the splanchnic fat, though there are sums in the flesh for a few species such as lamper eel and some species of tuna ( Pirie and Swaninathan, 1975 ) . Fish is besides low in concentrated fatty acids and oily angle in peculiar is an first-class beginning of long-chain omega-3 fatty acids with I±- linolenic acid ( ALA ) , Eicosapentaenoic acid ( EPA ) and cocosahexaenoic acid ( DHA ) to assistance in forestalling cardiovascular disease ( Brunner, 2008 ) . Fish can be rich beginning of I and some Mg, Ca and Fe are besides present. However, fish are more perishable due to the surface sludge by a mass of bacteriums covering the fish organic structure and the bacteriums resides in the digestive piece of land. In Malaysia, fish is an of import nutrient in the Malayan diet and besides devouring it as a dish itself it can be used as a condiment in assorted traditional signifier such as dried, salted and fermented.
1.2 Agitation
Agitation is the most conventional method in nutrient processing. It is a desirable procedure of
biochemical alteration by micro-organisms that bring alterations to nutrient and enhance belongingss such as gustatory sensation, olfactory property, shelflife and alimentary value. Through agitation, the safety of nutrient can be enhanced by taking their natural toxin constituents or by suppressing the growing of disease-causing bugs ( Adams et. al. , 2001 ) . Food agitation can be classified in several groups which is drinks, cereal merchandises, dairy merchandises, fish merchandises, fruit and vegetable merchandises, leguminous plants and meat merchandises. Fermented nutrients were developed by many civilizations for two chief grounds, that is to continue harvested or slaughtered merchandises which were abundant during those times and are scarce and the other ground is to better the centripetal belongingss of merchandises that are unappealing.
In Southeast Asia, agitation of fish the most common as fish is a major constituent in the human diet. Freshwater shellfish, marine fish and crustaceans are processed with salt to bring forth assorted type of fermented fish merchandises. Fish agitation produces a type of savoury spirit from Marine merchandises by utilizing both endogenous enzymes in fish and salt tolerant micro-organisms in the environment. Fish agitation is besides a method of continuing perishable fish and Marine merchandises in a high salt concentration ( Lee et al. , 1993 ) . Lactic acerb agitation plays a major function in continuing perishable veggies and fishes, guaranting its safety. The organic acids, chiefly lactic acid and acetic acid, produced by lactic acid bacteriums are effectual antimicrobic agents, and they cut down the pH in the nutrients to forestall the growing of most risky nutrient micro-organisms ( Lee et al. , 1994 ) .
1.3 Nonsom
Nonsom or bosou is a traditional fermented fish-rice merchandise made among the among the KadazanDusun-Murut community in Sabah. It is served during festival occasions such as Pesta Keamatan. The ingredients used to do this dish includes fish rice, salt and grinded meats seed of the Pangium edule. The procedure of bring forthing nonsom is simple. First the fishes are cleaned exhaustively and salted. Rice is added into the conoction and assorted exhaustively. Dried seed of Pangium edule besides known as pangi, with the content that is scraped out are pounded into a pulverization signifier and is so sprinkled onto the conoction to be assorted. The mixture is so transferred into a tightly close jar and kept for one month period before ingestion. Nonsom can besides be cooked by steaming, Fry with onions and chili or be eaten merely as it is ( Vivienne, 2007 ) .
One of the ingredients in nonsom is the seeds of Pangium Edule that are said to be toxicant due to presence of hydrocyanic acid which is toxic Pangi seed can merely be consumed after interventions such as boiling and soakage in running H2O ( Davidson and Jaine, 2006 ) . These seeds are forte in Indonesia and have been used as spices. It is claimed that the add-on of these seeds into the fermented nutrients helps in commanding the agitation procedure and supply alone spirit to the merchandises. The KadazanDusun community eliminates the toxicant of pangi by soaking and boiling them in H2O. They use the powdery seed of pangi as nutrient ingredients in the fermented fish merchandise. This gives a nutlike olfactory property on the fermented fish. The spirit beginning for spices is due to the dominant amino acids that is present in the fermented seed, which is Glutamic acid ( Andarwulan et.al. , 1999 ) .
2.0 SIMILAR PRODUCTS WORLDWIDE
2.1 Burong dalag.
In the Philippines a fermented rice-fish merchandise which involves lactic acid bacterium is served as appetiser, sauce or chief dish ( Melchor,2007 ) . Burong isda is a traditional fermented fish merchandise in the phillipines that is similar to narezushi in Japan. Burong isda is produced in white and ruddy signifier. The ruddy is by add-on of angkak which is a civilization grown in rice. Burong isda is prepared utilizing freshwater fish that is cleaned exhaustively and assorted with salt nightlong before blending with cooled cooked rice. The mixture is left to ferment for 7 to 10 yearss in room temperature. There are other sorts of burong isda based on the type of fish used. An illustration is Burong dalag, a fermented rice-fish mixture utilizing mudfish, Phicephalus striatus ( Sanchez, 2008 ) .
2.2 Narezushi
Narezushi is a fermented fish merchandise by fermented salted mackerel with poached rice. It was suggested that narezushi was developed as a mean of fish saving. In the past half century, Marine fishes has been substituted with fresh water fishes due to the drastic lessening of crop. Aji-no-sushi is another signifier of Narezushi that is made from Equus caballus mackerel ( Trachurus japonicas ) . The mackerel is gutted and put in a barrel that has been salted. It is so drained off and placed in a VAT filled with vinegar rice. The salting takes 3 yearss to 2 months and the desalting stage varied. The fish are stuffed and covered with cooked rice, scattered with a little sum of Nipponese Piper nigrum leaves or ruddy Piper nigrum and pickled in a barrel with the palpebra that is held closed by rock weights. The agitation period last from 6 hebdomads to 1 twelvemonth, depending on the maker ( Kuda et. al. , 2009 ) .
2.3 Sikhae
Sikhae in Korea is the lactic acid agitation of saltwater fish with cooked millet. The procedure of bring forthing is similar to other fermented fish-rice merchandises but millet is used alternatively of rice as it is the common saccharide beginning in the northeasterly state. Other ingredients added include minced garlic and ruddy Piper nigrum pulverization. Garlic shows antimicrobic consequence on most micro-organisms in natural stuff and the merchandise. It besides functions as a selective agent which explains that why lactic acid bacterium is dominant in sikhae agitation ( Lee, 1997 ) . Garlic plays double function in fermented fish merchandises by suppressing Gram-negative bacteriums and barms and supplying LAB less sensitive to garlic with a saccharide beginning for growing ( Puladan-Muller et.al. , 1999 ) .
The agitation last for 2 to 3 hebdomads at 20A°C. The pH of Sikhae beads rapidly due to the organic acids formed from the millet that provide fermentable sugar for lactobacillus. The merchandise can be stored up to one month at 5A°C after agitation. The disgusting fish olfactory property disappears and an acceptable spirit is formed during the agitation procedure ( Lee et.al, 1993 ) . Leuconostoc mesenteroidesA and Lactobacillus plantarumA are the lactic acids involved in the agitation of Sikhae. The function of these acid organizing bacteriums for the saving of fish is evident, but a more of import factor is their ability to bring forth acceptable spirit during the agitation procedure.
2.4 Plaa-som.
Plaa-som is a Thai fermented fish produced harmonizing to household or local geographic penchants, particularly in the cardinal, northeasterly and northern parts of Thailand. The fermented fish merchandise is composed of fresh water salt, boiled rice or cooked rice and Allium sativum. In Southern Thailand, another local assortment of plaa-som is produced. Palm sirup are used to replace garlic and poached rice, and from clip to clip by roasted rice ensuing in the resembles of another type of fermented Thai fish known as plaa-uan ( Paludan Muller et. al. , 2002 ) . In processing of plaa-som, all ingredients are assorted and left to ferment at ambient temperature ( 25-30 A°C ) for 3-5 yearss in a covered-lid cookery pot. The agitation spontaneously occur due to the presence of microflora, chiefly lactic acid bacteriums that is found in natural stuffs. Appropriate conditions are of import in order for the complete agitation by lactic acid bacteriums. For illustration the presence of saccharide and antimicrobic substances incorporating ingredients like salt and Allium sativum ( Kopermsub and Yunchalard, 2008 ) . Garlic is believed to move as an antimicrobic agent against certain gram negative bacteriums and exciting the growing of lactic acid bacteriums ( Paludan-Muller et. Al, 1999 ) .
2.5 Pekasam
Another similar merchandise to nomsom is pekasam that is localized in the province of Kedah, Perak and Kelantan of Peninsular Malaysia. Pekasam is made from fermented fresh water fish that is assorted with ingredients such as roasted rice, Tamarindus indica and salt. It is prepard by thorough cleansing of the fish and salted nightlong with 20-50 per cent of salt. Then the fish are drained before blending 50 per cent of roasted rice pulverization and some Tamarindus indica. The mixture is packed into an earthenware container in beds and allowed to ferment for 2 to 4 hebdomads. After agitation, the fish is consumed deep fried or made into a side dish ( Lee et.al. , 1993 ) . The tabular array below shows the composing of pekasam and the composing may change somewhat depending on the type of fish usage and method practiced.
Table 1. Composition of pekasam.
Composition
A
Approximate scope
pH
A
A
4.5 – 6.1
Lactic acid ( % )
0.1-0.4
Salt ( % )
10.0-16.0
Moisture ( % )
57.0-73.0
Protein ( % )
15.0- 25.0
Fat ( % )
3.0-8.0
Ash ( % )
A
A
6.0-14.0
A
Souce Zaiton ( 1980 )
During agitation procedure, lactic acid bacterium lowers the pH and preserves the merchandise. The presence of the organic acid besides contribute to the spirit of the merchandise. The formation of acid combined with the add-on of salt eliminate proteolytic and putrefying micro-organisms. The saccharide beginning that supports the growing of lactobacilli comes from the roasted rice pulverization which besides aid in dissembling the fishy olfactory property and coloring material development of the concluding merchandise. There is besides some dislocation of the fish protein by self-digestion to peptides and aminoalkanes. These compounds together with acids and merchandises formed by microbic agitation give rise to typical spirit and olfactory property of the pekasam ( Lee et.al. , 1993 ; Kuda et.al. , 2009 ) .
3.0 WHAT WERE DONE IN THE PAST.
Presently there are barely any surveies on the local autochthonal fermented fish-rice merchandises of Malaysia such as nonsom. The lone surveies made so far are the consequence of Pangium edule seed in the production of fermented fish by Ajik ( 1999 ) and the nutritionary content and physiochemical analysis of fermented fish of different species from different countries in Sabah by Joanis ( 2002 ) . The survey done by Joanis ( 2002 ) found that nonsom from Tamparuli utilizing Tilapia mossambica contained the highest food and mineral content. Most of the surveies were carried out on the seed infusion of Pangium edule whereby antioxidant activity were associated with mobilisation of lipoids and phenolic compound during agitation ( Andarwulan et.al. , 1999 ) . Harmonizing to ( Chye and Sim, 2009 ) study, there is a strong relationship between the phenolic compound of the seed extracts with the antioxidative and antibacterial activities. It was concluded that the phenolic infusions possess good antioxidant and antimicrobic activities which could be a promising beginning of natural preservative and be used in pharmaceutical industry. On the other manus, pekasam which is a similar merchandise of nonsom has already been studied on the agitation procedure and fast agitation method has been introduced whereby the merchandise can be ready in 2 to 3 hebdomads ( Che Rohani Bt.Awang, 2001 ) .
In other old work, there were surveies done on the microflora and chemical alterations in fermented fish merchandises during agitation. It is found that lactic acid bacteriums are the dominant micro-organisms involved in the agitation of fish-rice merchandises such as Plaa-rom, Narezushi, Burong isda, sikhae and in our local autochthonal fermented nutrient of Pekasam and Nonsom. The lactic acid bacteriums involved for each type of fermented merchandises are listed in the tabular array below. The function of lactic acid bacterium is to ferment available saccharides which lead to a lessening in pH that inhibits infective and spoilage bacteriums. The combination of low pH and organic acids nowadays is the chief factors that preserve fermented fish merchandises ( Paludan-Muller et. al. , 2002 ) .
Table 2: Type of lactic acid bacteriums found in fermented fish-rice merchandise.
State
Name of fermented merchandise
Findingss
Journal resource
Siam
Plaa-som
Parallel growing of barm and LAB was found. Pediococcus pentosaceus and Zygosaccharomyces rouxii are the prevailing lactic acid bacteriums and yeast species severally.
Lactic acid bacteriums initiates agitation followed by alcoholic agitation by Zygosaccharomyces rouxii.
Paludan-Muller et.al. , 2002
Japan
Aji-no-susu
It is reported to be a typical traditional lactic acid fermented fish merchandise and the lactic acid concentration was really high as compared to other narezushi merchandises. The prevailing bacterial groups were lactobacilli and lactococci.
Kuda et.al. , 2009
Korea
Sikhae
Leuconostoc mesenteroidesA and Lactobacillus plantarumA are the lactic acids involved in the agitation of Sikhae
Lee et.al.,1997
Phillippines
Burong dalag
The agitation is initiated by Leuconostoc mesenteroids and Streptococcus faecalis so followed by Pediococcus cerevisiae and eventually Lactobacillus plantarum.
Orillo and Pederson, 1968
Besides that, studies on different salt concentrations, presence of aminic acids and organic acids and besides beginning of saccharides influenced the agitation procedure of fermented fish-rice merchandises. In agitation with salt, the high salt content idiots microbic growing, hydrolysis of the fish protein is thought to happen by natural tissue enzymes, cathepsins. For low salt merchandises, halotolerant populations dwelling of Gram-positive beings will predominate. “ I- sushi ” which is fermented by assorted strains of lactobacillus has been associated with nutrient poisoning eruptions from toxin production by C. botulinus type E. ( Downes and Ito, 2001 ) . However, different fermented fish merchandises have different salt concentration demand. The sufficient sum of salt in agitation is of import as it influence the microbic growing and the rate of agitation which besides affects the centripetal quality and safety of the merchandise. Padulan-Muller et. Al. ( 2002 ) studied on the growing of microflora with different concentration of salt in Plaa-som, a Thai fermented fish merchandise. It is found that in high salt concentration of plaa-som, the growing of lactic acid bacterium was inhibited and this delayed the agitation procedure. This addition the hazard of growing for salt-tolerant potentially infective bacteriums, illustration Staphylococcus aureus ( Paludan-Muller, 1999 ) .Thus, 6-7 % of salt concentration is recommended for Plaa-som to ease the growing of LAB and rapid lessening of pH to below 4.5. However, different fermented fish merchandises have different salt concentration demand.
Aside from salt, the gustatory sensation of fermented fish-rice merchandise is enhanced during agitation due to the presence of organic acids and aminic acids. Harmonizing to ( Itou et. al. , 2006 ) research, it is reported that the pronounced addition of the extractive constituents and organic acids is thought to lend to the umami gustatory sensation and the rancid gustatory sensation of narezushi. The extractive constituents such as free amino acids and peptides increased unusually because of the decomposition of proteins in fish. As for the organic acid, it increased quickly due to the agitation of rice and pervasion into the fish meat. Lapp goes the gustatory sensation of Aji-no-susu where the predominant amino acids of alanine, lysine, leucine, glutamic acid and theronince were found and are of import in supplying the gustatory sensation of fermented fish merchandises ( Kuda et.al. , 2009 ) .
Fish contains small saccharide and therefore rice or millet that is used chiefly maps as a saccharide beginning for agitation by LAB for the decrease of pH in merchandises without indigeneous starter civilization. Rice is an of import beginning of saccharide to supply fermentable sugar for lactic acid bacteriums in the decrease of pH. High buffering capacity of the fish is besides reduced by the rice in order to obtain a rapid lessening of pH.The lessening of pH inhibits infective and spoilage bacteriums therefore preserve the fermented fish. The amylum from rice are hydrolyzed by the amylolytic activity found in lactic acid bacteriums by which is reported ( Olympia et.al. , 1995. ) that lactic acid bacteriums strains isolated from burong isda hydrolyzes soluble amylum, amylopectin, animal starch and pullulan. Addition of salt and spices such as Allium sativum or Piper nigrum may add to the safety of the merchandise. In another survey ( Paludan-Muller, 1999 ) describes the function of garlic that serves as saccharide beginning for lactic acid bacteriums in fermented fish merchandise. In garlic, a garlic zymosis Lb. Plantarum strain was found. This indicated that Allium sativum may be more of import than rice amylum as a saccharide beginning for agitation. Furthermore, garlic play double function in fermented fish by suppressing gram negative bacteriums and barms and Acts of the Apostless as a saccharide beginning for growing of lactic acid bacteriums.
The traditional method of fermented fish merchandise was based on self-generated agitation or by the usage of autochthonal starter civilization. The starter civilization serves as a beginning of a assortment of enzyme including amylolytic enzymes. Based on a survey ( Olympia et. al. , 1995 ) it was found that in strains of L. plantarum contains the L137-amylase enzyme that hydrolyzes both I±-1,4 and I± -1,6-glucosidic linkages in polyoses. The enzyme degrades the amylum to fermentable saccharides for the growing of lactic acid bacteriums in the agitation procedure.
Recently there has been surveies that mentioned the agitation procedure could be improved by utilizing a assorted starter civilization. In the fish sauce agitation a study from Yongsawatdigul et Al. ( 2007 ) found that strain of Staphylococcus sp. SK1-1-5 from proteases and bacterial starting motor civilization has the possible to be utilized as it can speed up the agitation without holding great consequence on the centripetal qualities of the fish sauce. Another research by Saithong et.al ( 2010 ) examined the usage of lactic acid bacteriums as possible started civilizations of plaa-som. The scientists discovered that plaa-som inoculated with the assorted starter civilization were found to incorporate higher sums of lactic acid after 24 H than plaa-som inoculated with individual starter civilization. This indicated the possible advantage of increased merchandise safety and quality in add-on to decrease in agitation clip. Furthermore, the combination L. plantarum IFRPD P15 and L. reuteri IFRPD P17 starting motor civilizations could besides suppress the growing of clostridium during plaa-som. As a decision, L. plantarum and L. reuteri have great possible to be used as starter civilizations in plaa-som and may perchance cut down agitation clip.
4.0 CHALLENGES
The autochthonal fermented fish-rice merchandises are largely produced in family or little mill graduated table with limited procedures to command and guarantee the safety and quality of the merchandise. Like other fermented merchandises, it is easy contaminated due to the presence of other harmful micro-organisms. Contamination can happen due to exposure to microorganisms from the environment during harvest home, processing, storage and distribution. Besides that, improper nutrient handling and deficiency of good hygiene patterns increases the hazard of microbic taint. For illustration, fish that is non eviscerated prior to agitation procedure are prone to spoilage since the natural stuffs are non cooked.
About all fish bourne botulism eruptions are associated with the ingestion of salted-dried or fermented fish that is consumed without farther cookery. Clostridium sp has been reported to pollute izushi, a fermented preserved fish with rice in Japan ( Downes and Ito, 2001 ) . Likewise in the Philippines, Staphylococcus aureus and Clostridium sp. which has been isolated from bakasang indicated that pattern of hygiene during production was hapless ( Salampessy et.al.,2010 ) .The end point from infective microflora present in the nutrient include negative effects such as spoilage, where the nutrient is unfit for human ingestion or hazard of wellness by infective or toxigenic micro-organisms being present. Proteolytic bacteriums such as Staphylococcus aureus and Clostridium botulinus cause microbiological jeopardies in fermented fish as both of these micro-organisms are associated with salt and natural fish used in the processing. Insufficient degree of salt concentration besides leads to growing of infective micro-organisms in fermented fish merchandises. At higher salt concentration there is a hazard for growing of Staphylococcus aureus and Clostridium botulinus type A and B.
Besides that, the manufacturers of the fermented fish-rice merchandises are non good educated on importance of proper handling and keeping good hygiene pattern to avoid cross-contamination during agitation procedure of the merchandise. They are besides non good cognizant of the unwanted alterations on the fermented nutrient may happen during processing and repackaging of the merchandise. Knowledge on the microflora which are involved in the agitation procedure of the fermented fish-rice merchandises are limited.
5.0 THE EMERGING NEED OF RESEARCH
Presently there are no surveies done on the nutritionary composing of certain autochthonal fermented fish-rice merchandises such as nonsom. Furthermore, there is no standardisation in the add-on of salt concentration since nonsom made from different countries of Sabah are based on personal penchants. Therefore, the concluding merchandise of this fermented fish-rice based merchandise may incorporate inordinate add-on of salt. In add-on, higher per centum of salt concentration was found to hold a slow or no lessening in pH, whereas a rapid lessening of pH was found in low salt concentration ( Paludan-Muller et al. , 2002 ) . However, Pekasam which is a similar merchandise to nonsoom has already been standardized in Malayan Food Act 1985 whereby it must non incorporate less than 10 % salt. Because of this, more research on this autochthonal fermented merchandise demands to be carried out for the standardisation and safety of the merchandise produced.
Following is the demand of bettering cognition base. Other fermented nutrient such as cheese, staff of life, beer and vino are good known and good developed. However for autochthonal fermented fish-rice merchandises, the cognition is hapless. Therefore, to hold a broader spectrum of understanding these autochthonal fermented merchandises, microbiological, nutritionary and proficient probe should be carried out on each procedure. The isolation and word picture of each being should be determined and should non contract to merely the dominant beings as other beings in little Numberss may incorporate of import map in the procedure. Understanding the functions of the micro-organisms in these fermented merchandises is of import as they mostly control the qualities of the fermented merchandises.
Besides, more research needs to be done on assorted fermented fish-rice merchandises to speed up the agitation clip by utilizing assorted starter civilization alternatively of depending on traditional self-generated agitation to bring forth the fermented merchandises. Researchs on starting motor civilizations by lactic acid bacteriums or commercial protease with bacterial starting motor civilization showed that there are great possible for the usage of these starter civilizations in speed uping agitation of fish merchandises ( Yongsawatdigul et. al.,2007 ; Saithong et.al.,2010 ) . Therefore, more research has to be made on the usage of these starter civilizations to other fermented fish-rice merchandises to speed up the agitation clip and without adversely impacting the centripetal quality.
6.0 STRATEGIC FOR CONTINOUS IMPROVEMENT.
The production autochthonal fermented fish-rice merchandise of nonsom has the possible to spread out and commercialized as more people are devouring the fermented nutrient and the gustatory sensation is acceptable. However, the procedure of fermented fish-rice merchandises are done utilizing traditional method so a more organized and specific method is required to upgrade the manner of treating the fermented merchandise.
For little graduated table industries that produce fermented fish-rice merchandises, execution of quality control of the processing and distribution is required based on Hazard Analysis Critical Control Point rules. New patterns can be added for betterment in Good Fabrication Practices. Good patterns in certain stairss and placing the possible critical control points for illustration lactic acid bacterium counts, pH and the length of ripening phase, for better production and higher safety criterions. Food animal trainers should besides be educated in line with on ( HACCP ) for commanding safety of the merchandise.
Besides that, to battle issues on safety of fermented fish-rice merchandises reseraches on the microbial and chemical alterations in these autochthonal fermented fish-rice merchandises are necessary in order to guarantee the safety and better the quality of the fermented merchandise produced. Findingss from research can be used as an index for the manufacturers to understand different phases of agitation procedure and safeguards to be taken to minimise the hazard of taint and maintain choice consistence of the merchandise.
Furthermore, a more safe production can be resulted if starter civilization are used. The usage of starter civilization in the agitation of fermented fish-rice merchandise could increase merchandise safety and quality as there is a rapid growing of lactic acid bacteriums and lower pH to a safe degree. In add-on, agitation clip is besides shorten.
