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POTENTIAL NUTRACEUTICALS AND FUNCTIONAL FOODS FROM FISHERY BY-PRODUCTS IN THE PHILIPPINES: STATUS AND TRENDS

EMILIA S. YAP

College of Fisheries and Ocean Sciences University of the Philippines Visayas (UPV)

Philippines

ABSTRACT

The paper discusses the present status and trends of potential nutraceuticals and functional foods from fishery by-products in the Philippines. The discussion starts with a brief introduction on the present status of the industry wherein the different post harvest handling and processing methodologies that are presently being used in transforming fishery by-products into food and non food products are reported. Emphasis is given to the different sources of wastes in the production chain from the source of raw materials to distribution facilities.

All of these activities that are related to the utilization of fishery by-products in the Philippines are in line with the government’s plans and strategies for the fisheries industry. In particular, provisions on the research and development activities using fishery by-products and other related activities are included in the Philippine Comprehensive National Fishery Industry Development Plan (2006-2025).

Research and development activities on the utilization of fisheries by-products in the Philippines are still on-going. Results of a survey on post harvest research activities in the Philippines indicate extensive utilization of fisheries by-products in the development of value added products and their utilization as potential neutraceuticals and functional foods. Although research gaps in the utilization of fisheries by products in the Philippines still exist, a closer look at the present industry scenario reveals the availability of several commercially important food/non food products from fisheries by-products in the local market.

There are clear indications that research and development activities on this field would continue in the future. Hence, given the current and future trends on utilization of fisheries by-products in the Philippines, control and regulation of products in the market must be given more due emphasis by proper authorities in the country. Key words: Fishery by-products, industry status, post-harvest losses

BRIEF OVERVIEW OF FISH UTILIZATION IN THE PHILIPPINES

Post-Harvest Handling and Processing Methodologies: Industry Status In the Philippines, there are different post harvest handling and processing methodologies that are presently being used in transforming fishery by-products into food and non food products. These methodologies typically involve one, or a combination, of any of the following: (1) reduction of moisture (i.e. salting, drying, smoking and fermentation); and (3) other processing methodologies (e.g. mincing, surimi processing, marinating/pickling, etc.) Likewise, direct extractions of natural bioactive compounds are being done in an attempt to explore sources of potential nutraceuticals and functional foods. In most of these activities, attention is focused on the use of fishery by-products.

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Post-Harvest Losses: Facts and Figures The need for the utilization of fishery by-products is quite apparent. Approximately 25-30% of the total fish production in the Philippines and else where, is lost from the distribution chain and such lost has to be compensated with the use or transformation of some of the recoverable by products. These losses can be categorized as: (1) actual physical or material losses, due to improper post harvest handling practices; (2) nutritional losses, due to the decrease in the amount of nutrients a human body derives from eating fish that has lost its nutritional value; and (3) losses in market value due to spoilage, infestation, weight loss, and inferior finished products.

There is still limited information on the actual extent of post harvest losses in the entire fisheries sector in the Philippines. However, although it has not been quantified in the literature, these losses are generally described as follows. In aquaculture facilities, loss in market value of the produce exists due to some traditional handling practices. Discards of by catch in both commercial and municipal fishing vessels significantly contribute to physical losses. There are also cases of spoiled/inedible fish found in fish landing facilities For instance, in the Navotas Fish Port Complex alone, ca 30% of some of the fish on auction generally suffer some physical damage due to improper post harvest handling (Kamari and Sayers 1979). Poor transport facilities and infrastructure, such as the unavailability of proper transport facilities and access roads from aquaculture facilities and fish landing sites to fish handling/processing facilities lead to quality losses due to physical damage. There are also limited cases of physical losses and losses in value as a result of rejection of aquaculture products in the export market, most likely due to unsanitary processing techniques or due to detection of antibiotics (e.g. chloramphenicol, nitrofurans, etc.) in aquaculture products.

LEGAL FRAMEWORK FOR THE UTILIZATION

OF FISHERY BY-PRODUCTS The Philippine Comprehensive National Fishery Industry Development Plan (2006-2025) Republic Act 8435 (or RA 8435 - The Agriculture and Fisheries Modernization Act of 1997) and Republic Act 8550 (or RA 8550 - The Fisheries code of 1998) provide the legal basis for the conduct of relevant research and development activities in the Philippines. In particular, RA 8435 includes Title 3 (Research, Development and Extension), Chapter 1 (Research and Development) which recognizes the need to “promote science and technology as essential for national development and progress”, while RA 8550 has Chapter V (Fisheries Research and Development), Section 82, creates the National Fisheries Research and Development Institute as the government’s research arm on fisheries.

Pursuant to the provisions of the two Republic Acts, in 2006, the Bureau of Fisheries and Aquatic Resources, in partnership with the Fisheries Improved for Sustainable Harvest (FISH) Project, a USAID technical assistance project in the Philippines, orchestrated the development of the Philippine Comprehensive National Fishery Industry Development Plan, 2006-2025 (CNFIDP). This is the industry plan which aims to make an exhaustive assessment of the industry status and give direction to Philippine fisheries for the next twenty (20) years.

The Fisheries Sector Development Framework. The Philippines is endowed with rich fisheries and aquatic resources that supply a significant amount of animal food protein to most of the Filipinos. Hence, the fisheries sector provides employment opportunities and good economic returns because of their export earnings. However, the sector has been confronted with the following problems: (1) depleted fishery resources; (2) degraded fishery habitats; (3) strong resource use competition; (4) unrealized full potential of aquaculture; (5) post harvest losses; (6) uncompetitive fish and fishery products in the local and global

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markets; (7) inadequate fishery rules and regulations; and (8) limited institutional capabilities and partnerships between the private and public sectors (CNFIDP, 2006).

The Philippine Comprehensive National Fishery Industry Development Plan, 2006-2025 (CNFIDP) that was formulated in 2006 provides a comprehensive framework for advancing the optimal development and long term sustainability of Philippine fisheries based on internationally accepted philosophy on sustainable development of natural resources. The plan presents the strategic direction for the sector for the next 20 years and specifies mid-term and long-term projects that would contribute to the strategic development of the Philippine fisheries industry. Mid-Term Priority Plans and Projects, with focus on natural products. Among other things, the post harvest component of the CNFIDP under Chapter 4, Section 4.1.4, has a specific project dealing with natural products and their potential uses (Yap, 2006). This project specifically focuses on the characterization of marine natural products. Activities include the determination of the levels of both micro and macronutrients in aquatic organisms and the data from which would be used to further showcase the importance of both commercially and non-commercially important aquatic organisms as a good source of table food items. Likewise, this project aims to jumpstart the inventory of the existing aquatic resources in the country and later on, to develop a database of the different aquatic organisms that are potential sources of bioactive compounds.

Related Fisheries Administrative Orders in the Philippines To date, no related Fisheries Administrative Orders that specifically deals with the utilization of fish processing wastes has been issued by the Philippine authorities.

RESEARCHES ON UTILIZATION OF FISHERIES BY-PRODUCTS IN THE PHILIPPINES: A REVIEW

Post-Harvest Research Activities in the Philippines An inventory of the different post harvest research activities was conducted in 2006 to determine the research trend and needs of the industry (Yap 2006). A total of 216 researches were inventoried from eleven (11) research and academic institutions in the Philippines. These researchers were done in a span of thirty (30) years.

Results of the survey show ten (10) commodity groups were well-researched during the period. As shown in Fig. 1, top target commodities of researchers/funding institutions include milkfish (18%), tuna (16%), small pelagics (16%), shrimps (13%), and seaweeds (12%). The remaining commodity groups, namely mussel/oyster, tilapia, cephalopods, crabs, and carp, constitute the remaining 25% of the researches surveyed.

In terms of post harvest methodologies, as shown in Figure 2, 36 out of the 216 researches (or 17%) dealt with raw material characterization while 24 (or 11%) were on waste utilization. Other research topics included the use of the different post harvest handling and processing techniques, value addition, and marketing (Fig. 2).

The research period surveyed was grouped into the following time periods: 1975-1979; 1980-1984; 1985-1989; 1990-1994; 1995-1999; and 2000-2006, to determine the research trend. As shown in Fig. 3, the following salient observations were noted: (1) researches on post harvest handling and low temperature preservation were highest in 1985-1989; (2) researches on traditional processing methodologies were up in 1980-1984, dropped in 1985 until 1999, but went up again in 2000-2006; (3) researches on non-traditional processing methodologies (i.e. product development, value addition, mincing, surimi process technology and waste utilization exhibit a steady increase in number from 1975 until 2006; and (4) there has been a increase in the number of researches, from 1975 to 2006, on raw material / product characterization.

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Fig. 1. Researches conducted from 1975 to 2006, using different

fisheries commodities. Values expressed as percentages of the researches surveyed, n=216 (Yap, 2006).

Fig. 2. Researches conducted from 1975 to 2006, using different handling and processing methodologies . Values expressed as percentages of the researches surveyed, n=216 (Yap, 2006).

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Specific Research on Utilization of Fishery By-Products The results of the survey clearly indicate that researches in the Philippines for the past several years are slowly, but are increasingly focusing on utilization of fisheries by-products in product development and value addition. This can be explained by the increasing demand for waste management efforts, coupled with the refocusing of researches on characterization of raw materials for their potential as either animal food protein source or as functional foods.

Most of the recent research efforts are focused on the utilization and characterization of different fishery commodities, but a good number of these researches concentrate on utilization of fishery by products and processing wastes in the production of neutraceutical and functional foods. Utilization of different raw materials as potential neutraceuticals and functional foods. Several researches have been conducted in the Philippines in order to characterize different raw materials and fishery products as potential neutraceuticals and functional foods. For example, research on polyunsaturated fatty acid contents of some traditional fish shrimp paste condiments of the Philippines product reported that fish paste derived from small shrimp fry (Acetes spp.) had the highest content of dietary DHA (Montano et al. 2001). More recent researches have also been conducted on the antioxidative activities in fish sauce (Peralta 2008, Peralta et al. 2007).

Researches on the functional properties of hydrocolloids and some bioactive compounds from seaweeds have been extensive. For example, there had been a research on the structure and functional performance of gigartinacean kappa-iota hybrid carrageenan and solieriacean kappa-iota carrageenan blends (Villanueva et al. 2004). An interesting research on kappa carrageenan showed the sequestering ability of this hydrocolloid against paralytic shellfish poison (Canete and Montano 2002). A research on metabolic effects of high fiber algal polysaccharides on blood sugar levels showed that incorporation of at least 12 g total

1975-1979 1980-1984 1985-1989 1990-1994 1995-1999 2000 - 2006

Fig. 3. Researches conducted from 1975 to 2006, using different fisheries commodities, based on different time ranges. Values expressed as numbers of the researches surveyed, n=216 (Yap, 2006)

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dietary fiber from agar can cause significant decrease in post-prandial glucose rise in humans (Panlasigui et al. 1998).

In terms of the characterization of microalgae, biological and phytochemical screening of the extracts of Chaetoceros calcitrans had been conducted by Seraspe et al. (2007). Several uses of different microalgae are also noted: (1) as antibiotic, wherein extracts of Nannochloropsis sp. are used against Vibrio harveyi, the causative agent of luminous vibriosis in penaeid shrimps (Seraspe et al. 2007) and the use of green water technology with blooms of the beneficial microalgae Chlorella in shrimp ponds was found to suppress the growth of V. harveyi; and (2) as potential sources of biofuels (Toledo et al. 2010).

Researches on crabs aim to characterize the specific substances present in common toxic crabs species in the Philippines (e.g. Asakawa et al. 2007, Gomez-Delan et al. 2007, Quilantang and Azakawa 2007). Utilization of fishery by-products as potential nutraceuticals and functional foods. Use of fishery by-products as health promoting substance has been extensively studied in the Philippines. In particular, there have been several researches on characterization of polyunsaturated fatty acids in fish (Santos 1991), fishery products (Montano et al. 2001, Panggat 2000) and fishery by-products. In particular, fishery by-product sources of PUFAs, in addition to fish livers, reportedly include tuna heads and eyeballs (Panggat and Rivas 1997), pond-cultured milkfish eyeballs, heads and livers (Guirgen 2000), and sashimi processing wastes (Panggat and Shindo 2002).

Fishery by-products can also be used as dietary supplements – as a calcium source from the backbones, fins, and offals of several fish species. Milkfish processing wastes were reportedly useful as dietary supplements in making human food products (e.g. Calmorin 2000, 1999) and in making fish meal and silage (e.g. Mendoza and Taruc 2003, Santos et al. 1977). Tuna by products were found to be good sources of fish glue and calcium concentrate (e.g. Cerbo 2000, Ayon 1994). Fish protein concentrates from different fish species are likewise used as dietary supplements in human and animal foods (e.g. Orejana et al. 1985). Appreciable amounts of ascorbic acid were noted in the processing waste of Gracilaria heteroclada (Tejas and Yap 2003) while skipjack stickwater was reported as a potential source of flavoring ingredients (Obligar 1999) and sea shrimp heads as a source of shrimp flavor concentrate (Nunal 2001).

As a source of functional microorganisms, nata-producing microorganisms were isolated and characterized from pulps of Gracilaria sp. (Mamaril 1998).

A functional food additive in the form of fish protein hydrolysates reportedly increase the net weight and improve the appearance of canned skipjack tuna (Yap 1996). Chitosan, a widely used biomaterial with an established safety profile in humans, had been reportedly effective as a pharmaceutical excipient, a controversial weight loss supplement, an experimental mucosal adjuvant and in a hemostatic dressing (see Zaharoff et al. 2007). However, in the Philippines, researches are just on its infancy stage, for it is only at the level of extraction of chitin/chitosan on a laboratory scale (e.g. Finalla 2002, Quintos 1996, Nuqui et al. 1995, Malicdem 1995). Research gaps in the utilization of fishery by-products. A closer look at the present status of researches in the Philippines, the following aspects need attention in future researches: (1) There is a compelling need to focus on basic research, with emphasis on the exploration

of possible bioactive substances in water and solid wastes from fish processing plants. (2) The need of the aquaculture industry for more sources of probiotics could be answered by

looking at the application of microbial ecology in studies of fish gut microflora and the possible use of probiotics to improve resistance against fish diseases.

(3) Studies on the characteristics of seaweed processing wastes and their application as fertilizers or as neutraceutical and functional ingredients in human and animal foods could be done. This is not only to tap these waste materials as potential sources of neutraceutical and functional ingredients, but as a way to alleviate the present problem of waste disposal.

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(4) There has to be comprehensive studies on fish gelatin from waste materials from tuna processing plants and its potential uses.

(5) Functionality testings of the different ingredients must be conducted for possible commercial application of these research findings.

INDUSTRY SCENARIO: EXISTING FOOD/NON-FOOD PRODUCTS

FROM FISHERY BY-PRODUCTS Available Products in the Market Research activities, conducted both by the private sector and in research institutions in the Philippines, led to the production of several consumer products. For example, several non-food products from fishery by-products are now produced in the Philippines. These include fish meals from tuna canning wastes and leather from fish skin. Consumer food products are now commercially available in the market and these include fish crackers from skin of tuna and dried marinated fish bones. Protein concentrates from fish and shrimp processing wastes found their ways in feed manufacturing establishments. Likewise, encapsulated fish oils are widely marketed in the Philippines.

In 2007, a patent on the utility model for the “Seaweeds-based Air Freshener Gel” was awarded to two (2) researchers (Patent No. UM-15501: Dr. Marco Nemesio Montaño and Ms. Banaag A. Glorioso-Lajera of the Marine Science Institute, University of the Philippines). This utility model employs seaweeds as the base material in air freshener gels.

Control and Regulation of Products in the Market Despite the presence of several products in the market, no specific Fisheries Administrative Orders (FAOs) on their regulation is yet drafted. Table 1 provides a list of the existing FAOs, issued by the Bureau of Fisheries and Aquatic Research that are related to all post harvest activities in the Philippines.

Given the current and future trends on utilization of fisheries by-products in the Philippines, as noted above, control and regulation of products in the market must be given more due emphasis by proper authorities in the country.

Future Trends In the Philippines, the vast marine resources have long been exploited. However, these marine resources have not been commercially tapped as potential sources of natural products. Hence, the real potential of marine organisms in the Philippines has yet to be established.

However, there are clear indications that research and development activities on this field would continue in the future. The country’s efforts to characterize some marine organisms with no perceived commercial values – in terms of their potential as a good natural source of micro and macronutrients and bioactive substances – have to be sustained. While the nutritive and industrial values of important marine organisms in other countries are well-documented, recent researches in the country are trying to populate and fill in the gaps on the present limited information about the characteristics of the Philippine marine organisms that make them important sources of natural products.

Indeed, the future of Philippine aquatic species as important natural sources bioactive substances that may have a wide variety of industrial, food, pharmaceutical, neutraceuticals and biotechnological applications looks promising.

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Table 1. List of fishery post-harvest related Fisheries Administrative Orders (FAO) issued by the Bureau of Fisheries and Aquatic Resources (BFAR), pursuant to the provision of Republic Act No. 8550 (or the Philippine Fisheries Code of 1998).

FAO No. Year of

Implementation Title

FAO No. 195 1999 Rules and Regulations Governing Importation of Fresh Chilled / Frozen Fish and Fishery Aquatic Products

FAO No. 199 2000 Guidelines on Fish Transshipment FAO No. 209 2001 Guidelines on the Production, Harvesting, Handling,

and Transportation of Shellfish for Implementation of the Local Government

FAO No. 210 2001 Rules and Regulations on the Exportation of Fresh, Chilled, or Frozen Fish and Fishery/ Aquatic Products

FAO No. 211 2001 Requirements for Pre-Processing and Processing Plants the SSOP thereof and the Processing and Quality Requirements for Shellfish

FAO No. 212 2001 Guideline on the Implementation of HACCP System

FAO No. 213 2001 Establishment and Maintenance of BFAR’s Quality Control Laboratories and Collection of Fees and Charges for Examination Services

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