Annex: The role of naphire in coordinating national post harvest research extension and training in the Philippines

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The National Post Harvest Institute for Research and Extension (NAPHIRE) was established on May 24, 1978 by virtue of Presidential Decree No. 1380. The creation was prompted by the enormous losses being incurred in the post harvest handling of grain, which had been estimated to be within the vicinity of 10-37% from harvesting to consumption. Additionally, improved post harvest systems and facilities should be developed to sustain the gains achieved in food production.

NAPHIRE's actual operation started two years later and in the same year (May 1980), it was attached to the National Food Authority (NFA) through Letter of Implementation No. 123 for better program coordination and for financial and logistical support.


NAPHIRE is charged with the function of accelerating grains post harvest technology improvement through the generation and application and application of appropriate post harvest technology, to reduce losses and improve food and feed quality.

Hence, NAPHIRE undertakes research and extension on post-harvest primarily covering the areas of food and feed protection; post harvest facilities design and development, and; post harvest systems and analysis and development. NAPHIRE's efforts are directed to alleviate these priority problems in the grains post production industry: wet grain handling: pest infestation in storage; inefficient and expensive storage and handling systems; lack of socio-economic studies on the use and non-use of post production equipment and facilities; and the need for extension activities to facilitate the adoption of post harvest technologies.

Local and international seminars, workshops and other training programs have been conducted for various sectors in the post harvest industry. Such activities are significant in continuously developing awareness of the need for action on post harvest loss reduction programs.

One of the most significant developments in NAPHIRE's effort to improve the country's grains post harvest industry is the establishment of the National Post Harvest Research and Training Center which now stands as the core of post harvest R & D programs in the country.

Therefore, NAPHIRE shall be to GRAINS post harvest technology what the National Rice Research Institute is to production.


The Institute is headed by an Executive Director who has overall responsibility for directly managing all the affairs of NAPHIRE.

NAPHIRE is governed by a Board of Trustees which provides direction and support to the Institute's programs and activities with the Administrator of the National Food Authority (NFA) as Chairman; and the following as members: the Secretary, Department of Science and Technology (DOST), the Chancellor, University of the Philippines at Los Banos (UPLB); the President, Central Luzon State University (CLSU); the President, Confederation of Filipino Rice and Corn Association, Inc. (CONFED); and the Executive Director of NAPHIRE.


1. To promote and establish scientific methods and techniques in grains handling storage and processing.

2. To initiate the development of low-cost post harvest facilities by tapping indigeneous resources.

3. To design and develop processing equipment/machineries necessary in promoting product/ byproduct utilization.

4. To conduct researches in the development of local capability in the area of support activities such as the manufacture/fabrication of graders, pest control equipment, testing instrument and the like.

5. To conduct basic and applied researches on all phases of grains post harvest distribution and utilization.

6. To establish definitive manpower training programs for effective post harvest operations.

7. To establish and disseminate research findings and recommend improvenents related to grain post production distribution and utilization.


From a program initially confined to research, NAPHIRE has expanded its activities. At present, its activities are classified into the following categories:

1. Research

2. Education and Training

3. Technology Dissemination and Utilization

4. Institutional Development and Technical Assistance (to alimited scale only)

To undertake all these activities, NAPHIRE has solicitied significant grants from international donors such as:

1. International Development Research Centre of Canada (IDRC)

2. The Royal Netherland Government (RNG)

3. Australian Centre for International Agricultural Research (ACIAR)

4. Asean-European Community Regional Collaborative Programme on Grain Post Harvest Technology (AECRCP)

5. Europen Economic Community (EEC)

6. Asean-Australian Economic Cooperative Programme (AAECP)

7. Asean-Grains Post Harvest Programme (AGPP)

8. World Bank (WB)

9. Asian Productivity Organization (APO)

10. Overseas Development Administration through TDRI (Tropical Development Research Institute) of U.K. Government, now Natural Resources Institute (NRI).

Other sources of funds come from the National Government and the National Food Authority (NFA).

Two possible fund sources are:

1. Japanese International Cooperation Agency (JICA)

2. French Government


NAPHIRE's research program is aimed at providing better understanding of the nature, causes, and magnitude of post harvest losses and developing appropriate solutions to minimize these losses. Th research program has covered the following areas:

1. Food and Feed Protection (FPD)

2. Post Harvest Facilities Design and Development (PHFDD)

3. Post Harvest Systems Analysis and Development (PHSAD)

4. Training and Extension Department (TED)


In its ten years of existence, NAPHIRE has continued its commitment to the food postharvest the development goals of the industry. It has conducted and - evaluated training programs designed to upgrade the knowledge and skills of the various sectors in the food industry.

The training courses being offered are:

1. General training course on grains postharvest technology.

2. Specialized training course on grains postharvest technology.

3. Local and international workshops, seminars and technical symposia.

4. Individual coaching or apprenticeship

5. On-site training courses

6. Staff development programs

A national postharvest training center was established through the joint effort of the national government and the EEC and serves as the venue for the above training activities. It is equipped with training laboratories, furnished with modern postharvest laboratory equipment and a dormitory for training participants.


In order that results of research could reach the intended users and be utilized effectively, NAPHIRE is conducting the following activities:

1. Pilot extension of developed technologies

This is true for the developed corn sheller; the recommended pest management strategies; and the proposed warehouse stock inventory control.

2. Communication and publication program


Considerable researh findings on rice and corn postproduction technology had been achieved by NAPHIRE. While the result of these researches have made some impact in terms of reducing postharvest losses, these available technologies have not been widely adopted by end-users, primarily the farmers and grain processors.

NAPHIRE fully recognizes this, hence, the Institute implements its research activities with a training and extension program which is equally significant.

These are primarily disseminated through intermediaries like the extension agents of related agencies which have direct linkage with farmers, and which have existing extension networks all over the country. Extension arms of these agencies serve as conduits of postharvest information.

The Institute conducts training courses which directly benefits end-users. It has for instance, conducted a series of seminars nationwide on efficient grain handling for NFA field personnel, grain postharvest technology for agricultural colleges and universities, special courses for MERALCOCORFARM personnel. Training courses shall also be packaged in the very near future for traders/millers. Information dissemination is likewise conveyed through mass media like newsletters, press releases, technical bulletins, slide sets and photo exhibits.

The message contained in these information materials are aimed at developing understanding and interest in the urgency of reducing postharvest losses.

Clearly, NAPHIRE's presence in the food industry lends strong support to the government and the private sector's sustained efforts in increasing food production.

Admittedly, we still have far to go, the need to arrest food wastage through proper and improved postharvest technology and facilities is NAPHIRE's pressing concern. Hopefully, however, we believe that the government, hand in hand with the private sector can work together to minimize food wastage in the grains industry.

Summing all these, NAPHIRE's vital role in the development o the grain industry cannot be over emphasized.


1.a Grain Quality Deterioration in On-Farm Level of operation

A two-phased study was conducted to determine the nature, causes and extent of paddy quality deterioration at the farm level. In Phase I (the field study), three systems of post-harvest practices served as the treatments: System 1 simulated the existing flow of on-farm post-harvest practices; System II, the delay in threshing that employed different types of field stacking of freshly harvested paddy and System lll, the delay in drying where threshed, undried grains were stored in the farmer's storehouse.

In Phase II, field conditions were simulated in the laboratory to determine the effect on yellowing and other discolorations of paddy and milled rice, brought about by fungi identified in the field study. These fungi were Aspergillus flavus, Fusarium sp., Curvularia sp., Helminthosporium sp., Rhizopus sp., A. terreus and A. Ochaceus.

Results showed that when freshly harvested paddy was immediately threshed and dried as in System I, the percentage of yellow kernels was negligible. However, when threshing and drying of paddy were delayed as in System II and lll respectively, the percentage of yellow kernels significantly increased. The high moisture content (m.c.) of paddy at harvest, the high relative humidity and the type of field stacking used greatly contributed to the rate of yellowing. Yellowing was also found to more prevalent during the wet season.

Yellowing was observed as being caused by heating within the field stacks brought about by the combined respiration of paddy and micro-organisms. It starts right in the farm and is more pronounced when wet, unthreshed paddy is stacked in conical shapes or "mandalas" in field.

Results also showed that the growth and activity of fungi caused the following discoloration in paddy and milled rice: yellowing of milled rice from paddy incoculated with Fusarium sp. and Aspergillus flavus; yellowish brown color in milled rice from paddy inoculated with Rhizopus sp. and black color in milled rice from paddy inoculated with Curvularia sp., Aspergillus flavus and A. ochraceus.

1.b Paddy Deterioration from Procurement to Storage (Yellowing)

The study was conducted to determine the nature, causes and extent of paddy deterioration from procurement to storage, involving two systems. System I simulated a delay in drying where newly procured high moisture paddy with 20-25% moisture content (m.c.) was stored for one month without drying. In System II, dried paddy with 14-18% m.c. was stored for one year and longer.

Yellow kernels increased when drying of wet paddy with 20-25% m.c. was delayed. The increase was higher and faster in paddy with 23-25% m.c. than in paddy with 20-22% m.c. The 2% NFA maximum yellowed kernels was reached after a one-week delay in drying for paddy with 23-25% m.c., and after a onemonth delay in drying for paddy with 20-23% m.c.

For System II, paddy with initial m.c. of 17-18% had more yellow kernels than paddy with 14% and 1516% m.c. The yellow kernels reached 2.3% during the 6th month of storage. No increase in yellow kemels was observed in paddy with 14% m.c. even after one year of storage. Furthermore, the number of damaged and chalky kernels in milled rice decreased as paddy was stored longer. The decrease is due to the reduced weight of the grains caused by breakage during milling.

Results indicate that yellowing is caused by the activities of microorganisms whose life is sustained by the high moisture content of paddy. Hence, the higher the moisture content, the faster is the yellowing process and the greater the number of yellow kernels.

Yellowing can be prevented by immediately drying the paddy to 14% m.c. before storage.

2. Maize Deterioration at On-Farm Level of Operation

The study aimed to determine and investigate the nature, causes and magnitude of maized deterioration on a time frame during farm level operations. It was conducted in South Cotabato and Isabela. In South Cotabato, the experiment was carried out by setting up four systems simulating the normal flow of operations in the area, shelling and drying delays and an ideal condition of handling maize after harvest. In Isabela, only the normal flow of operations was followed.

Results of the study showed that the existing farm practices in South Cotabato and Isabela greatly affect the quality of the grains produced in the two areas. The occurence of moldy and discolored grains and aflatoxin contamination was higher in South Cotabato while the mechanical damage grains was higher in Isabela.

Insect infestation was not much a problem at the farm as manifested by the minimal weight loss noted after two weeks.

The simulation experiment revealed varied quality and value losses. Drying delay yielded 5.69% and 6.56% moldy and discolored grains respectively, with a value loss of i, 0.36/kilo and aflatoxin contamination reaching the 20 ppb level on the second day of storage. Shelling delay, on the other hand, had 2.99% moldy grains, 3.8% discolored grains, a value loss of i, 0.19/kilo and the 20 ppb aflatoxin was reached 8 days after the harvest. With the normal flow of operations in the area, moldy grains was 3.5%, discolored grains was 4.0% value loss was P 0.23/ kilo and 20 ppb aflatoxin was reached 6 days after harvest. Immediate shelling and drying maize after harvest gave the highest quality grains and least losses.

3. Maize Deterioration at Off-Farm Level of Operation

The causes and magnitude of losses in maize at the off-farm level of operation were investigated. Maize loss assessment study was conducted in two premiere maize producing areas and two corn processing centers. Maize samples were taken from local traderassemblers, wholesalers, millers and other maize processors.

The highest mean percentage of weight loss caused by insects was noted on samples taken from storage warehouses of wholesalers with an average of 1.5%, and a range of 0.01% to 21%. Yellow maize was found to be more susceptible to insect infestation in storage than the white variety. Yellow maize stored for six months incurred an estimated weight loss of 9.04% and 69.10% insect lost 5.01% in weight, and 47.86% of its kernels were damaged by insects. The Economic Threshold Level (ETL) for yellow and white Maize were reached at 1.64 and 1.57 months respectively. On the other hand, the Economic Injury Level (EIL) were attained at 1.87 months for yellow maize and 1.93 months for white maize.

Generally, all maize reaching the trade channels were positive for aflatoxin. Regional differences on aflatoxin contamination existed. Maize with nontolerable level of aflatoxin was more prevalent in samples originating from Southern Mindanao (74%) than in Cagayhan Valley (51%). An inverse relationship between the price of maize grits and aflatoxin contamination was noted.

In ability of farmers and traders to promptly dry the grains to a safe level of moisture content (13% to 14%) was identified to be the root cause in speedy maized deterioration. Recommendations are outlined directed towards the solution of the major problems identified.

4. Rodents Losses in Commercial Grain Storage

The field survey revealed that the average population and consumption of rodents and 111. individuals and 3.16 kilograms of grains, respectively. Likewise, stomach contents of rodents in government warehouses were found to have 99.5 per cent grain while those collected from private warehouses contained 90 per cent grains. The Norway rat, Rattus norvegicus Berkenhaut and the Philippine ricefield rat, Rattus rattus mindanensis Mearns were the prevalent rodent species found in storage.

Laboratory experiments showed that rodents consume an amount equivalent to 10% of their body weight per day and, while feeding, spill 7.5 times as much as the amount they consume. it was also found that grains contaminated with rodent hairs, urine and faeces were infected with Aspergillus flavus and A ochraceus.

A -control program consisting of chronic poison baiting, in-warehouse reduced losses by 87%. A costbenefit ratio of 1.36 was achieved by implementing the control program for six months.

5. Bird Pests and their Control in Storage

The study aimed to determine the extent and nature of birds and develop a control strategy.

Results revealed that the most dominant bird species damaging grain in storage is the Phillippine weaver, Passer montanus. Warehouses visited were found to harbor 50 to 400 birds each, so daily losses range from 0.28 to 2.2 kg in each warehouse.

An integrated control program consisting of: a) providing physical barriers, to prevent easy access of the birds to the warehouses, b) maintenance of hygiene and sanitation inside and around the warehouse was developed.

6. Assessment of Paddy Loss in Storage

The study was conducted to determine the extent of grain quality deterioration due to the biological factors in storage and to pilot test the proposed warehouse stock inventory control system.

Quality of paddy from procurement to ten months storage were evaluated through physical analysis, microbial analysis, fat acidity value (FAV), and alkali test. Existing warehouse operations were simulated to assess quantity losses.

Results showed that the storage of paddy with 14% and 15% moisture content resulted in only slight changes in the quality of rice. Yellowing of grains can be slowed down by providing aeration in the pile.

Losses due to respiration of the grains, insects, birds, rodents, poor handling, moisture loss associated with dry matter loss and changes in moisture content were accounted in the proposed system of inventory. Results revealed that this system could provide a more realistic estimate of losses provided that all warehouse documents are complete, true and correct.

7. Insect and Mite Pests and Their Control in Commercial Storages

The study was conducted to identify insect and mite species, associated with grains and grain products in storage determine the extent of losses in rough rice and maize at various lengths of storage period, establish the Economic Insury Level (EIL) and Economic Threshold Level (ETL) in paddy and maize programming fumigation, and develop a control program to reduce losses in storage due to insect infestation.

A total of 31 species of insects and 13 species of mites were found in the survey. One species of insects and four species of mites are new records from the Philippines.

The lesser grain borer, Rhizopertha Dominica (F) has gained primary importance in the safe storage of rice. It has attained dominance over Sitophilus spp.. This new situation calls for the modification of present pest control strategies and relevant warehouse management practices.

Estimations of population density of insect pests inside the stacks can be obtained through direct sampling of stocks. Other monitoring techniques found to be a potential substitute to this method were visual inspection and the use of traps e.g. Iight traps, corrugated cardboard traps and Zoecon "pherecon" traps.

A direct association between the age of rough rice and maize stocks, and level of insect damaged kernels, and the age of stocks and percent weight loss were observed. The ETL and EIL for fumigating rough rice and corn were established based on the derived linear association between percent weight loss and number of insects. The ETL was determined at 2.02 months in rough rice and 0.35 months in maize. The EIL was attained after holding rough rice for 5.18 months in storage. In maize, the EIL was established at 0.9 months in storage. The benefit from every peso invested from fumigating rough rice and maize are P 3.62 and P 1.17, respectively.

Quality assessment of rice revealed that the fat content (FAV) and gelatinization temperature (BEPT) of brown rice and milled rice increased significantly with time. In rough rice and opposite trend was observed. The gel consistency of all form of rice decreased significantly as the storage period was prolonged. The effect of insect damage on the FAV, BEPT and gel consistency however, was found to be insignificant.

Recommendations have been outlined to serve as guideposts in the modification of insect control strategies in the light of the present findings and observations.

8. Integrated Use of Pesticides In Grain Storage in the Humid Tropics

Pests continue to be the major cause of losses incurred in storage and it is suggested that pesticides will continue to be of much use in aiming to reduce these losses. The emergence of malathion resistant strains in our storage indicates the need to regularly revise insecticide treatments to counter the development of insecticide resistance. An effective system of pesticide usage therefore is necessary for safe storage of grains.

Grain mixture technology has been succesfully carried out in Australia and other parts of the world. In the Philippines such technology was tested with, modification so as to fit NFA operations. Treatment of grains (corn and paddy) were done in the conveyor of bulk storages and was bagged for final storage. The most likely grain protectants previously screened by a series of laboratory tests were used. Tested were three synthetic pyrethroids (deltamethrin, permethrin and methacrifos) and one carbamate (carbaryl).

Methacrifos and deltamethrin were applied as single treatments. The others were applied as combination treatments, one having a broad spectrum effect while the other in low concentration was to combat insect resistant strains. They were also synergized with piperonyl butoxide (PB). Thus, combination treatments used were: permethrin + chlorpyrifos-methyl + PB; fenitrothion + fenvalerate + PB and pirmiphosmethyl + carbaryl. The dosage applied is the amount that will provide protection against infestation for a period of 8 months for maize and 12 months for paddy.

Results showed that combination treatments were better than single treatments although biological response of test insects was dependent upon the kind of test species used. Although insects were present in treated piles at the end of storage period, losses were reduced to 60%. At the maize experimental piles, it was further observed that while the control pile was already infested with Trogoderma granarium (khapra beetle), the treated piles remained free from infestation. Its absence in all treated piles was highly noticeable.

Benefit-cost analysis showed that all treatments were economically viable. It is also disclosed that combination treatments were better than single treatments since it has the effect of lowering residue contamination and reducing costs.

For maize, combination treatment of fenitrothion + fenvalerate + PB was the most effective with an incremental BCR of 14.07 while for padd, the best treatment was permethrin + chlorpyrifosmethyl + PB with an incremental BCR of 7.02.

9. Kinetics of Decay of Candidate Pesticides for Integrated Pest Control Program

The use of chemical pesticides is still the mainstay in large-scale control of most insects and other pests of economic and public health importance. Hence, demands and use of grain protectanis have increased significantly because these are are required to prevent subsequent infestation when mixed with the grain (Champ and Dyte, 1976). However, their extensive use has resulted in a number of serious problems including the development of insecticideresistant insects and presence of unwanted chemical residues which are toxic not only to target pests but also to humans.

The study aimed to understand the fate and distribution of insecticides during storage of tropical grains.

Incidentally, it compliments the previous project on the "Integrated Use of Pesticide" servicing its chemically oriented requirements.

Samples from the experimental stocks were assessed for residue level. Sampling was done during insecticide application (at five minutes interval) and at the start of storage and at a sixweek interval thereafter until the end of storage period which was eight months for maize and twelve months for paddy.

Significant losses of insecticides during application were measured after the assessment of residue level. The decline of residues from the initial sample was not due to rapid initial decay of pesticides as the interval between treatment and sampling was only five minutes, but is attributed to spraying where some of the aerosols drifted away from the grains being treated. Degradation of pesticide is also possible during transport of samples from treatment site to the laboratory.

The residues determined for both trials showed an exponential dependence of decay of pesticides with time of storage. The decline in concentration of insecticides was observed to be rapid at the start of the period followed by a relatively slow phase. This trend in degradation appears to follow first order kinetics, in which the rate of decay (rate of reaction) of pesticide at anytime is directly proportional to the concentration of the residue present which is expected.

Results for both trials also revealed that pyrethriods are more stable than the organophosphates. This is in agreement with published reports that organophosphates are generally unstable due to the high rate of volatization and susceptibility to photolytic decomposition. Volatization is one of the most important pathways responsible for the decay of insecticides from grains. It is favored by high vapour pressure of insecticides, presence of moisture, increased air movement and high temperature. It is therefore appropriate to note that the humid tropical climate of the country mobilizes the insecticide, thus making them easily degraded.

Likewise, the kinetic study show that the calculated half-life, t, (the time for the pesticide to decay half to its initial 1/2 value) and the rate constant, k, for each protectant were relatively close to the predicted values (Desmarchelier and Bengston) especially for paddy. There are some variation in the values, and one possible reason is that it is harder to establish the kinetic behaviour of pesticides in field trials. For maize, the result was not as satisfactory as that of paddy because of the gap in the time of analysis. Analysis of maize samples was stopped for one year.

Another result obtained which is of particular interest and importance, is that the residues determined for maize and paddy were very much below the maximum tolerance level recommended by the Codex Alimentarius Commission of the Food and Agriculture Organization (FAO) on food commodities for safe animal and human consumption.

10. Long Term Storage of Grain Under Plastic Covers

Insect infestation is a serious problem commonly encountered in large government and private trader warehouses, expecially when commodities are kept for a long time. Presently, the problem is alleviated by chemical control measures. However, the injudicious application of pesticides can lead to a rapid decline in their effectiveness, due to the development of insect resistance. Hence, other non-chemical control measures have to be explored.

NAPHIRE launched the project "Long Term Storage of Grain Under Plastic Covers" in collaboration with the Commonwealth Scientific and Industrial Research Organization (CSIRO), and the National Food Authority (NFA) with financial assistance from the Australian Center for International Agricultural Research (ACIAR). This project assessed the technical applicability and socio-economic feasibility of storing stacked, bagged rice and maize grains under sealed plastic enclosures, using carbon dioxide (CO2) to control insect infestations and preserve the grains quality under Philippine conditions.

Two trials with a duration of from 8-10 months and 14-15 months respectively, have been concluded. However, statistically tested information/ results are available only from the first trial. The analysis of samples gathered from the second trial is still in progress.

Among the significant observations are the following:

1. Per cent (%) weight loss is milled rice is significantly higher in the untreated or control piles (2.36%) compared to the treated pile (0.64%)

2. Per cent (%) insect damaged grain in paddy is slightly higher in the untreated piles (4-5%) compared to the treated piles (1.8-3.4%). Likewise, the % weight loss is higher in the untreated piles (0.62-2.26%) as against the treated piles (0.22-0.83%).

3. Per cent (%) insect damaged grain in maize is higher (5-9%) in the untreated piles and lower (4.3-6.0%) in the treated piles. However, the extent of weight lost did not significantly differ.

4. Comparison of the initial and final density of insects in the treated piles showed no significant increase. Moreover, the treated piles of milled rice and corn have significantly lower insect populations as against the control piles.

5. Significant reduction of microbial infection was observed in the treated piles of paddy and corn.

6. There was no significant difference observed in the milling recovery between the treated and control piles of paddy at the end of the experiment.

11. Effect of Controlled Atmospheres on Quality of Stored Grain

In the Philippines, rice and other food grains are commonly packed in bags and stored in stacks. This method predisposes the grains to insects and other agents of deferioration. As a result huge losses are incurred in storage, particularly in large commercial ones.

The sealed storage technique has known advantages over the traditional method of storing bag stacks. However, the dearth of information on the effect of this technique on grain quality inhibits its more widespread use. Hence, the determination of reliablility of sealed storage technique in terms of protection from insects must be supported by the determination of the effect of this technique on grain quality.

This project aims to determine the influence of atmosphere in combination with moisture and temperature on grain quality.

The development of sealed storage technique in the Philippines has involved several trials: In the first trial, stacks of milled rice, paddy and maize were sealed in PVC-membrane enclosures and disinfested with carbon dioxide, the stacks of paddy, milled rice and maize were stored unopened for nine (9), eight (8) and eight (8) months, respectively. Grain samples taken at the time of opening were unchanged by the storage procedure, there being no obvious nor significant quality changes. Moreover, the cooking characteristics of stored samples did not change.

The same commodities and storage technique but longer storage periods (over a year) were used in the second field trial. The quality of grain samples taken from this trial is now being assessed.

12. Mould and Aflatoxin Build-up in Maize

The project aims to control aflatoxin contamination in maize through the development of appropriate post production practices and facilities at the on and offfarm level at the maize assembly points of traders and government procurement agencies. This is being conducted in the three main maize producing areas in South Cotabato.

The existing post harvest operations in three areas are being closely monitored for the wet and dry season to determine the effect of different stages of operations at the on and off-farm level on mould and aflatoxin formation. A study on the storability of grains at moisture content level is being carried out. Piling of 100 bags each of maize at four moisture content levels, and breaking of piles at one three and six months of storage has been accomplished. Control and treated piles were set up to determine the effect of insect infestation in storage on aflatoxin formation.

A grading and screening study at traders level was carried out in 1988 to determine the most suitable screening and grading procedures that will include aflatoxin as important parameters during grain procurement.

13. Groundnut Industry: Philippines.

The biological aspect of the project intends to control aflatoxin contamination in groundnuts through the establishment of the required practices in the post production handling and primary processing phases. Field and storage experiments were conducted at the peanut farms and Madella Peanut Planters Cooperative Warehouse in Madella, Quirino, respectively.

In the field experiment, different treatments varying the types and duration of windrowing were established.

The storage study made use of 8 piles, 50 bags each, stored for 3 months. This determined the effect of the different moisture contents and unsound nuts combination on aflatoxin build up. The level of aflatoxin contamination and the mold infection was monitored from harvest to storage.

14. Aflatoxin Contamination in Peanuts at the Post Production Level of Operations

This study is part of the project on Groundnut Industry Economics; Phase 1. It determined the causes and extent of aflatoxin formation at each stage of the post production operation. It was carried out through a survey at the farmers, traders and processors level.

The results revealed that aflatoxin significantly increased from harvest to farm storage during the main cropping season. At harvest, peanuts contained, on the average, 3.16 ppb aflatoxin. The level continued to increase at the rate of 1.5 and 1.4 ppb per day during windowing and farm storage, respectively. Aflatoxin contamination was significantly higher during the main cropping season.

At the traders level, samples from the middlemen contained 35.00 ppb aflatoxin. Samples from the wholesalers had 188 and 275 ppb aflatoin for the newly procured peanuts, and peanuts stored for 3 months, respectvely.

At the processors' level, raw materials for table peanuts (roasted and fried peanuts) contained 7.73 ppb aflatoxin; peanuts intended for peanut butter contained 17.13 ppb aflatoxin and rejected peanuts contained 120.6 ppb aflatoxin.

Results of the survey indicated that aflatoxin contamination commerced at harvest. Aflatoxin reached level significant amounts at the traders and processor level. The continued increase in aflatoxin was attributed to insufficient drying of peanuts after harvest.


NAPHIRE has been closely investigating the inefficiencies in the post harvest systems in order to establish program priorities for practical and continuing improvement in the industry. Projects under this program thrust are being undertaken by the Post Harvest Systems Analysis and Development Department of the Institute.

15. Socio-economic Study on the Utilization of Mechanical Dryers

The socio-economic constraints in the use and non-use of mechanical dryers at farm and mill levels, and how these could be overcome to enhance mechanical dryers utilization, were determined through survey case studies and feasibility studies.

Surveys showed that the major constraints by previous users of mechanical dryers at farm and mill levels were: 1) high fuel cost; 2) lack of understanding on the mechanical drying technology resulting in poor quality of dried paddy and difficulty in operation; 3) compatibility of drying capacity with the volume of paddy to be dried.

Among the non-users, limited volumes of procurement and low production volumes were the reported constraints by millers and individual farmers, respectively. The unavailability of mechanical dryers in the area also prohibited individual farmers to use dryers.

Conversely, continued users recognized the benefits and advantages of mechanical dryers, such as increase in volume of procurement during the wet season, maintenance of paddy quality and better price for good quality milled rice.

An in-depth analysis of operating dryers in the case studies revealed that the successful use of mechanical dryers required the following: large volume of paddy, dryer operation integrated as support to existing milling and marketing operations, compatible dryer capacities with volume of paddy to be dried, and lastly, sufficient technical knowhow in operating of the dryer.

Feasibility studies of mechanical dryers also showed that profitbility of different types of dryers was dependent largely on the level of operations to which they were matched, and the proper integration of the drying operation in the overall operation of the system.

16. Socio-Economic Factors Affecting the Utilization of Post-Harvest Equipment in the Maize Industry

A survey was conducted in three major maize producing areas in the Philippiness: South Cotabato, Bukidnon and Isabela. The study determined the existing post harvest marketing flow of maize from production to consumption; identified the various socioeconomic and physical factors and the extent of their influence on the use and non-use of improved maize post harvest technologies and; determined the necessary requirements for the design development and sustained utilization of improved post harvest technologies for the maize industry.

Users and non-users of mechanical shellers and mechanical dryers were interviewed.

The study revealed that mechanical shellers were popularly used in South Cotabato and in Bukidnon, but not in Isabela. The farmers and millers in Isabela were still using manual shelling because of the following constraints: the type of sheller introduced to them was producing poor quality grain, and produces broken cobs which they use for household fuel. In addition, the design of the equipment was very complicated and required frequent replacement of parts resulting in additional costs.

Two types of mechanical shellers were found in South Cotabato and Bukidnon: stationary and mobile types. The mobile type was common in Bukidnon, due to the fact that the average farm size in that area (Bukidnon) was bigger, (24.7 ha.) compared to South Cotabato, (6.61 ha.).

The stationary type sheller is bigger in capacity ranging from 40 to 200 cavans (2-10 tons) per hour while the mobile type had a capacity ranging from 30 to 60 cavans (1.5-3.0 tons) per hour.'

Users of mechanical dryers were found in the trading and processing centers of maize; such as Cagayan de Oro (4 units), Cebu (5 units), South Cotabato (3 units), and Bukidnon (9 units). However, out of the total users (21), 50% stopped using mechanical dryers. Reasons given for the non-usage of mechanical dryers were as follows: high operating cost, poor pricing scheme/lack of incentive for dried maize. For non-users, the following reasons were given: high investment cost, lack of incentive for dried maize mixing the wet and dried maize, availability of alternative drying such as corn drib, and unavailability of the dryer itself.

Contributing factors in poor marketing structure which discouraged the producers and even the traders to produce and maintain good quality grains were as follows: presence of market for wet and poor quality grain and ineffective pricing scheme/ineffective grading system.

17. Paddy Loss Assessment at the Farm Level of Operation

The reduction of paddy losses brought about by the introduction of newly developed post-harvest practices and facilities were assessed. Paddy losses incurred by the new technology, both quantitative and qualitative were compared to the traditional methods of post-harvest operations prevailing at Isabela and lloilo provinces, Philippines. The on-farm post-harvest operations considered were harvesting, piling, threshing and drying.

The costs and benefits derived from the application of both traditional and improved postharvest practices and facilities were evaluated in a systems study so that an appropriate combination of traditional and improved methods of an on-farm post harvest system, that which is socially and economically acceptable and entails a minimum loss, could be established and recommended.

The assessment of losses revealed significant reduction of about 3.08% quantiative grain losses in the threshing and drying operations. Better paddy quality resulted when the new facilities were used.

In the experiment, simulating in threshing delay and drying, the Grade I initial quality of paddy deteriorated to Grade II and Grade II to Grade lll classifications in just 2 to 4 days of delay, respectively.

Economic indicators showed profitability and high returns of investment for the new improved facilities. Payback periods, breakeven points and benefit-to cost ratios showed favourability in the adoption of the improved post-harvest practices and facilities at the farm cooperatives level or for the custom service investor.

Eight combinations of traditional and improved methods were identified to comprise the general alternative post-harvest systems. Economic justification in the selection of the most appropriate combination of an on-farm post-harvest system was made using the benefit-to-cost analysis for all systems. Guidelines to test the post-harvest systems' social acceptability and usefullness were recommended.

18. Pilot Testing of an Improved Mobile Maize Sheller

Pilot testing of the improved mobile maize sheller developed by NAPHIRE was instituted to investigate its economic viability and social acceptability; to establish the most viable system of utilizing the sheller and; develop the most appropriate extension strategy for its wider adoption.

Isabela and South Cotabato were chosen as pilot sites, located in the northern and southern Philippines, respectively. System I, a scenario depicting a sheller deficit area, and System II, a scenario exemplifying an area where several existing mechanical sheller in commercial operations were typified, in the respective provinces. A cooperator in each site was chosen to manage the sheller. Daily records of its operation were gathered and used in the economic analysis.

Regular interviews were conducted to obtain the social acceptability of the sheller. Users and observers alike at the pilot site were randomly interviewed in the study.

Result of the study revealed that the developed sheller was economically viable and socially acceptable economic indicators showed that the sheller obtained a 54.20% return on investment, a benefit cost ratio of 1.73 and payback period of 1.84 years, in System 1.

The adoption of the developed mobile sheller in areas where existing mobile shellers abound was slow. An increase in capacity for the developed sheller was recomnended for it to be viable. Sensitivity analysis showed that the developed sheller (at 40 cavans per hour capacity) would incur a negative return investment. A 70 cavan per hour capacity would make the sheller more economically viable.

The wider adoption of he developed sheller was recommended in areas typical to conditions exemplified by System I and a modification on the capacity for the sheller to be competitive in areas typical to System II.


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