Tips and Guides

At the end of the nineteenth century, several plant species were introduced into the Philippines. These came from different parts of the world and included fruits, vegetables and medicinal plants. Some proved to be valuable and easily adapted to the Philippine conditions while others were less promising and did not gain a wide acceptance among the populace. One of the introductions which proved to be suitable to the Philippine soil and climatic conditions was the avocado.

Known as ‘aguacate’ in Spanish and ‘alligator pear’, ‘Palta pear’, ‘Midshipmans butter’ and ‘avocado’ in English, it is called as ‘abokado’ in the Philippine vernacular. It was introduced into the Philippines in 1890 by the Spaniards through seeds coming from Mexico. However, it was only from 1902 to 1907 that avocado was introduced successfully into the Philippines by the Americans. Through the Bureau of Agriculture (now the Bureau of Plant Industry which is under the Department of Agriculture), planting materials were received from Hawaii, Costa Rica and the United States. In 1913, the Bureau of Agriculture, together with the College of Agriculture of the University of the Philippines Los Baos, started the countrywide spreading of avocado trees. Now, avocados are found growing all over the country, most of which are cultivated in backyards.

Varieties

The avocado varieties in the country have been developed mainly through introduction and selection. Many varieties have been introduced since 1903 and most of them have been lost. Today, only a few varieties exist. Most of them are selections from local seedling trees, and they are confined to only a few nurseries and backyards. These are:

* Cardinal: The fruit bottlenecked with an average weight of 400 grams. The skin is reddish-purple and thick (1.3 mm). The seed is small (40 g) and is loose to tight in the cavity. The flesh is yellow, moderately fibrous and constitutes 80 per cent of the whole fruit by weight. Read more…

Gulaman Making

Procedure:

1. Select freshly harvested seaweeds gathered early in the morning or during low tide.
2. Wash the seaweeds with freshwater and drain thoroughly.
3. Spread the seaweeds into thin layers over wooden trays or in any clean container and dry under the sun for one week.
4. Resoak seaweeds in freshwater for 5-10 minutes. Dry again under the sun until the
seaweeds turns dirty yellow.
5. Once the seaweeds are dried, bleach them with weak acids like vinegar until the color turns olive green.

A one-tenth kilo of dried seaweeds is either soaked in a solution of 3.5 liters of water an 90 ml of 0.1N sulfuric acid or soaked in a solution of half a liter water and 2.5 grams of commercial sodium thiosulfate.

6. Drain the bleached seaweeds and sun-dry until sufficiently dried (light brown in color)
7. To the dried seaweeds, add 3-5 liters of water and a diluted solution of vinegar until slightly acidic to taste. Allow this to boil for 30 minutes to one hour while constantly stirring the solution. Boiling can be repeated until the solidification of the extracted agar is difficult to achieve.
8. After boiling, strain the seaweeds using ordinary cheesecloth. Separate the liquid portion from the plant residue.
9. After extraction, allow the filtered extract to cool and solidify. Once it is hard enough, cut into strips or to any desired form.
10. Pack the gulaman strips or bars into an ice box with dry ice or wrap them in cheesecloth with ice and salt, keep the bars intact for 2-3 days.
11. Thaw the gulaman bars by placing them on bamboo mattings or wire screen and allow them to dry at room temperature.
12. Finally, allow the extracted thawed agar to dry under the sun until the desired texture is obtained.
13. Cool the gulaman bars before packing and storing.

OTHER PRODUCTS FROM SEAWEEDS

New products from seaweeds were developed by the Marine Bio-Organic Group of the University of the Philippines Marine Science Institute. Three of products are now being patented, while other seaweed-based food, fertilizer and personal-use products are now ready for commercialization.

1. Seaweed-based air freshener gel (Seamoy). This is a low-cost air freshener with a gel-like texture. It makes use of sweet floral scents that give a clean, fresh smell to rooms, cars, lockers’ and cabinets. Whole seaweeds are used in its manufacture (instead of polysaccharide extracts) making production cost low. Since the base allows a slow release of the essence, shelf life is prolonged. Unlike crystal air fresheners in the market, Seamoy can easily be divided into desired shapes and sizes for easier packing and use.

2. Fruit-flavored candy-gels (fruity cubes). These are jelly candies that are gummy-textured and come in different colors. Their flavors can be enjoyed by people of all ages. These are easy to manufacture and production cost is low. The polysaccharide used enhances the gummy texture better than gelatin.

3. Pastilles (Euginto). These are made from polysaccharides derived from seaweeds and
local throat soothing substances. The manufacturing process is simple. The gummy texture is similar to that of imported pastilles. The materials used are locally available and the production cost is low.

4. Menthol ointment (Ginhawa). This is a non-greasy, soothing ointment that uses polysaccharides as a base for substances, such as menthol and camphor. The polysaccharides used can replace the greater percentage of the usual compounds used as ointment bases. Thus, the formulation not only reduces the adverse effects between excipients, it also reduces possible allergic reactions of the user to the compounds. Production cost is similarly low.

5. Seaweed-based fertilizer (Algro). These are fertilizers that use the by-products of seaweeds processing. These fertilizers contain growth-promoting hormones and are fortified with nitrogen (N), phosphorous (P) and potassium (K) needed by plants. The production process involves the use of pre-treatment wastes in agar/carrageenan production (or the slightly basic extract of old or enzyme-degraded brown seaweeds); waste that would otherwise be discarded. Water soluble, these fertilizers use only natural components that do not harm the soil.

6. Suppository base. This is a modification of the common suppository base formulations. It uses natural products, with carrageenan as the emulsifier and binder in place of gelatin. Once molded, it requires little refrigeration to retain its shape. It does not easily melt even at room temperature. Melting time at body temperature is comparable to that of gelatin suppositories.

7. Skinless longganisa (Longsarap/Carraniza). This is a high-fiber native sausage that contains refined and semi-refined carrageenan as a fat substitute. It allows the substitution of vegetable protein for an equal amount of pork meat. The product reduces the consumer’s calorie intake and it is highly recommended for people on a low-fat diet.

8. High-fiber pandesal (Pan de lusog/Pan de Carr). This pandesal contains refined and semi-refined carrageenans that has a higher fiber content and longer shelf-life than ordinary pandesal. Its high fiber content is an aid to diabetic who wants to maintain a blood glucose level.

9. Liquid soap/shampoo (Halimuyak/Humot). This is a shampoo base prepared from biodegradable substances and seaweed polysaccharides. The seaweed polysaccharide as a viscosity enhancer that gives better body to the finished product. By reducing the use of synthetic soap bases and using seaweeds instead, production cost is reduced. In addition, seaweed use poses no danger to the environment when disposed while providing the user with the usual cleansing effect of ordinary soap. The new products from seaweeds are the result of the transformation of research into useful, potentially profitable goods and commodities.

Source: da.gov.ph, photo courtesy of www2.bishopmuseum.org

by Junelyn S. de la Rosa

Today, more and more farmers are going into mud crab farming. Studies have shown that mud crab farming is a very lucrative business with a 1.54 return on investment in only 60 days. Scientists from the College of Fisheries and Ocean Sciences of the University of the Philippines in the Visayas (UPV) have prepared a guide in starting a mud crab hatchery.

Mud crab species:

There are four kinds of mud crabs in the Philippines: the king crab (Scylla serrata), the purple crab (S. tranquebarica), the orange or red crab (S. olivacea), and the rare green mud crab (S. paramamosain). Among the mud crabs, the king crab is the most popular for its fast growth and flavor and is called an “export winner” for its high demand in the international market.

Hatchery/nursery facilities

Tanks for broodstock maturation, rearing, spawning, nursing, and for holding water should be constructed. They can be made of concrete, fiberglass or wood with dimensions of 0.5 to 1 cubic meter. The number of tanks should depend on the number of larvae and crablets that you are planning to produce.

Food production

Mud crabs feed on phytoplankton and zooplankton. Thus, in any hatchery one must learn how to culture phytoplankton to ensure that there is enough food for the mud crab juveniles. The first step to phytoplankton culture is obtaining an algal starter from laboratories or institutions that are selling them.

Chlorella, Nannochloropsis, and Tetraselmis are the common algae. You can start culturing them in one-liter capacity bottles. When the phytoplankton has bloomed and the density is 3 to 5 x 105 cells/ml, transfer them to ten-liter carboys. Upon reaching the same density, they should be transferred to a 0.5 to 1 ton- tanks where they will be allowed to bloom more.

In culturing phytoplankton, maintain the water temperature from 20-25 °C for indoor culture and provide good aeration to give enough supply of carbon needed for plant growth. And use boiled or filtered seawater with a salinity of 25-30 ppt for the culture and sterilize all the containers before use.

Also, for bigger culture, use urea (21-0-0) and ammonium phosphate (16-20-0) to supply the essential nutrients needed by the algae.

Broodstock management and spawning

The major source of broodstock is the wild-caught post juveniles or half-grown crabs while adult or berried female crabs are used as spawners. A minimum weight of 200 to 300 grams for broodstock and 450 grams for spawners are desired.

The king crab is sexually matured when the width of its carapace reaches 14 cm and it weighs 450 grams while the other mud crabs can spawn even if its carapace is still below 10 cm and weigh 300 grams.

As soon as the broodstocks and spawners of the king crab arrive at the hatchery- they place them in the tanks at 300 spawners per tank and 1000 broodstocks per tank with a 10 cm sand substrate at the bottom. Feed them daily with mussel meat (Perna viridis) at 5% to 10% of their biomass. Change the water (at least 30%), scrub the sides of the tank and remove excess feed daily.

Mud crabs become mature and mate when they are 4 months old. In ponds or tanks, male and female crabs clasp for 5 to 7 days to fertilize the eggs.

There are two methods of spawning: the natural and the induced. In the natural method, the mud crab is left in the tanks until they become sexually mature and spawn. For induced spawning, the most common method used is ablation where one (unilateral ablation) or both (bilateral ablation) of the mud crab’s eye stalks are crushed or cut to induce spawning 7-13 days after fertilization.

The advantage of unilateral ablation is that the mud crab can spawn again while in bilateral ablation the mud crab dies after hatching the eggs. In both cases, observe the mud crabs closely until the eggs fill the abdominal flap.

Since ablation increases the appetite of the mud crabs, feed the mud crabs more until the eggs are hatched. Incubation ranges from 7 to 13 days. At this time, the berried (pregnant) crabs should be transferred to another tank without the substrate. Expect the eggs to hatch when the eggs turn from light orange to dark grey.

After the eggs are hatched, transfer the larvae into the large tanks filled with 5-10 tons of filtered seawater with 34 ppt salinity. Add algae and rotifer at a rate of 5 x 10 (3) cells per cubic meter and 25 ind/ml, respectively. Yeast-grown rotifer may also be added at 5 ind/ml. Give supplemental diet of 6 grams/ton/day and feed them at 6AM, 12 NN, 6 PM and 12 MN.

Rearing of larvae in nursery

Line the nursery tanks with soil (10 cm thick) inoculated with lab-lab. For large tanks, line them with mud substrate that has been seeded with lab-lab. Apply lime and chicken manure at 2 kg/ 10-ton tank and ammonium phosphate at 500 grams per tank. After fertilization, transfer the megalopae at a density of 20,000 to 30,000 per cubic meter. Apply organic fertilizer to encourage the lab-lab to bloom.

For those using hapa nets as nurseries, use hapa nets with a mesh size of 1 mm and a dimension of 1m x 1 mx 1.5 m. Install the nets in a canvass-lined earthen pond. Line the hapa net bottom with 3-5 cm thick mud substrate. Apply chicken manure and inorganic fertilizer (16-20-0) at a rate of 20 g to 500 g /cubic meter. Fill the pond with water until a depth of 20 cm to promote growth of microbenthic algae that will serve as food for the larvae. Other organisms such as bloodworms, oligochaetes could also serve as food for the larvae. Harvest by totally draining the pond.

Source: “A guide to hatchery and nursery production of mud crab (Scylla serrata) juveniles” by Romeo Fortes, Juliana Baylon, Evelyn Marasigan, Allan Failaman, Gerome Genodepaz, Sol Garibay and Gisela Ann Mamon of the College of Fisheries and Ocean Sciences at the University of the Philippines in the Visayas, Miag-ao, Ilo-ilo. Photo: www.todayaqua.com