Physico-Chemical and Biological Changes During Co-Composting of Model Kitchen Waste, Rice Bran and Dried Leaves With Different Microbial Inoculants

Abstract

Disposal of food waste either by land-filling or incineration will cause environmental pollution and engaged in high treatment cost. Composting can be a viable food waste management, however, less research works have focused on the degradation of small scale kitchen waste. In this study, co-composting of model kitchen waste, dried leaves and rice bran were inoculated with four different sources of microbial inoculants (MI) namely commercial Effective Microorganism (EM), Tempeh, Tapai, a mixture of Tempeh and Tapai and water as a control. It was found that the temperature of all four composting materials with MI can be heated up to a higher temperature (>50 o C) than the control and produced less offensive smells. All composts ended with a neutral or weakly alkaline pH value (pH 7 -8) and a C:N ratio of around 10 which indicating the maturation of composts. For enzymatic activities, the highest activity of amylase (73 -129 U/g) and cellulase (75 -148 U/g) occurred at the beginning of the composting process. The maximum activities of lipase (5 -10 U/g) and protease (46 -72 U/g) were at the middle stage of the composting process. The germination indexes of the five composts were larger than 100% indicating non-phytotoxic. Although the temperature profile and odour performance were outstanding in the presence of MI, most other parameters did not show significant differences when co-compositing of small scale model kitchen waste was carried out with an adequate initial C:N ratio and moisture content. Further study is needed to distinguish the potential beneficiary effects of MI for the composting of kitchen waste. Nevertheless, the comparable performance of Tempeh and Tapai with EM in composting suggested that Tempeh and Tapai can be used to substitute the function of EM as a cheaper and more available microbial source for the household.Keywords: composting, kitchen waste, effective microorganisms, tempeh, tapai Abstrak Pelupusan sisa makanan sama ada di tapak pelupusan atau pembakaran akan menyebabkan pencemaran alam sekitar dan menglibatkan kos rawatan yang tinggi. Pengkomposan merupakan cara pengurusan sisa makanan yang berpotensi tetapi kerja penyelidikan terkini kurang memberi tumpuan kepada degradasi sisa dapur yang berskala kecil. Melalui kajian ini, sisa model dapur, daun kering dan dedak padi telah dirawat dengan empat sumber mikrob yang berbeza iaitu komersial Mikroorganisma Efektif (EM), Tempeh, Tapai, campuran Tempeh dan Tapai dan air sebagai kawalan. Didapati bahawa suhu keempat -empat bahan kompos yang dirawat dengan inokulan mikrob boleh mencapai suhu yang lebih tinggi (>50 o C) berbanding kawalan dan menghasilkan bau yang kurang busuk. Semua kompos telah berakhir dengan nilai pH yang neutral atau beralkali lemah (pH 7-8) dengan nisbah C:N lebih kurang 10 yang menunjukkan kematangan kompos. Untuk aktiviti enzim, aktiviti tertinggi amilase (73 -129 U/g) dan selulase (75 -148 U/g) berlaku pada awal proses pengkomposan. Manakala, aktiviti maksimum lipase (5 -10 U/g) dan protease (46 -72 U/g) berad...

Biotransformation of food waste into biofertilisers through composting and anaerobic digestion: a review

“…The results suggested that the utilisation of fermented food has a comparable effect and can substitute the commercialised effective microorganisms (EM) as a biofertiliser. The microbial inoculants from tempeh and tapai can degrade the food wastes and increase the germination index of radish seeds (Fan et al 2016).…”

Experimental Evaluation of Industrial Mushroom Waste Substrate Using Hybrid Mechanism of Vermicomposting and Effective Microorganisms

“…Agaricus bisporus wheat straw residues and rice straw and hulls. [15,16] Pleurotus sp. soybean straw, coffee pulp, corn fibre, cottonseed hulls, groundnut shells, and maize straw.…”

“…It was then stored at room temperature for 8 to 10 days, away from direct sunlight, and absorbed actinomycetes during activation at the top of the surface with a pleasant smell and a pH below 3.3~3.5. [15].…”

“…6a, which shows that the EM maintained the minimum requirement of thermophilic stages in all the sets and due to aeration effects, higher biodegradation activity is possible during the loading period [8] in the feedstock via the heat generated by the microorganism population's respites, and substrate breakdown is possible [1][2][3]. Again, it was seen that the temperatures of all the sets began to drop at the beginning of the third week, suggesting the maturity of the organic matter as demonstrated by the mass reduction in compost volume and odour emission as well [15].…”

“…The FTIR analysis of the mushroom waste substrate compost samples was used to examine the existence or absence of a functional group, as well as the degradation or stabilization process. [15,28]. The presence of an aromatic region indicates that stable compounds are being formed.…”