61. Document No. STAT/FOOD/7 “Assessment of Losses in Grain Post-Production Systems” was presented by Mr. Rosendo S. Rapusas.
62. The Experts were given an overview of the need to estimate post-harvest losses in grain post production system, the different types of losses, stages at which losses occurred and the several factors which were to be considered to obtain accurate results.
63. It was mentioned that increased grain yields brought about by the introduction of modern high yielding varieties coupled with advances in production technologies had put pressure on existing traditional post-production systems, particularly on harvesting, threshing, drying, storage and milling facilities. As a consequence, tremendous grain losses had been incurred that negated production gains.
64. In the 1970s, a lot of information and data on post-production losses had emerged and the seriousness of these losses had been recognised at the national and international levels. Inspite of these developments, information on the patterns, magnitudes and causes of post-production losses remained highly variable and the loss figures claimed were alarmingly large. The validity and relevance of these loss estimates were questionable as they were based either on expert opinions or on limited observation and/or poorly designed studies.
65. It was also made clear that statistical data on post-production losses were needed to evaluate whether or not the prevention of post-production losses as a policy for increasing food availability existed. In addition, the usefulness of accurate data was there to create awareness of the need to allocate resources to post-production programs and for identifying priority areas for action.
66. It was reported that there were five main types of food losses, namely, physical loss, reduced milling quality, poor observable quality characteristics, nutritive deterioration and development of toxins. But there was general consensus that major emphasis in loss assessment studies should be on physical loss and reduced milling quality as both have major economic implications.
67. It was mentioned that physical or quantitative losses did occur in the sequence of rice post-production operations. For harvesting, the loss components were shattering loss, lodging and standing crop loss, field stacking loss, and transportation loss. For threshing the potential losses comprised the unthreshed, scattered and loose straw and chaff losses. Drying loss was mainly due to scattering, improper or careless handling and consumption by birds, rodents and insects. Storage loss referred to weight reduction, which might be due to birds, rodents and insects. For milling, the loss was mainly the reduction in milling yield, which might be attributed to the type of milling machine, improper operation or poor quality of paddy.
68. In the measurement of post-production losses, several factors were to be considered to obtain results with reasonable accuracy. These included the selection of field plots and size, time of harvest, collection of grain samples for laboratory analysis, labeling of the grain samples and other related issues.
69. In order to evaluate the impact of alternative post-production technologies, all the samples collected during the field trials were to be analyzed in the laboratory against a set of standard criteria. Grain standards might vary from country to country and in the case of the Philippines, these criteria had been outlined in the paper.
70. In conclusion, it was mentioned that the loss assessment methods presented required sufficient time, energy and money to plan, organize and implement. The skill and training of field staff and their dedication to the loss assessment exercise determined the accuracy of results. Dependability of the measuring instruments and other laboratory equipment was also important. The continued support and cooperation from farmers participating in the field trials contributed to the success or failure, and the degree of accuracy of the different loss estimates made.
71. It was noted that assessment of losses in grain post-production systems was an integral part of the food policy issue and that there was paucity of information about crop losses. Recommendation was made to fill data gaps existing in post-production losses.
72. As there were various kinds of post-production losses and collecting information on each of them was not possible, it was recommended that type of post-production loss incurred be translated into monetary terms to keep track of those that were economically significant. In view of the importance of other cereals in contributing to food security, the assessment of losses should cover the other major crops, in addition to rice.
