EFFICIENCY ENHANCEMENT OF SILAGE MAKING FROM FISH WASTES

Abstract

The present study was to investigate the suitability of using fish wastes as raw material for silage making. To describe some of the major engineering and physical aspects of ensiling process, the following factors were considered as follows: four different mixing ratios of fish waste with rice bran, 1.5:1, 2.34:1,3.35:1 and 4:1; three different formic acid additions 2, 3 and 4%; four diverse pressing pressure 7.85, 12.75, 17.65 and 22.56kPa; two unlike packaging color white and black and three dissimilar ranges of temperature 25 – 35, 35 – 45 and 45 – 55oC during harvesting time. The experimental results showed that the best mixing ratio of fish waste with rice bran was 3.35:1 which gives moisture content of 62.3%wb. The shortest ensiling period of 25 days was achieved at pressing pressure of 22.56kPa, formic acid adding of 4% and black coverage color. However, the ensiling period tremendously decreased under controlled surrounding temperature at a range of 45 – 55oC at the 9th day; the pH of silage material was 3.25,total volatile fatty acid was of 1.95g/kg dry matter, Lactic acid bacteriawas 6.2g/kg dry matter, crude protein was of 36.12%, maximum temperatureobservedat the end of fermentation period at the 6th day was of 36.1oC, minimum temperature was at the 9th day was of 23.4oC at 9th day (harvesting day), the intensity of illumination value was of 44.5, 47.3, 53.3 and 58.3 lumen/m2 at material thickness of 4cm at fermentation time of 3rd, 6th, 9th and 12th day respectively.