Conservation and recycling of pomegranate seeds and shells for value addition

Anaerobic digestion of de-oiled cake of pomegranate seeds (10% SS) has been carried out at 35 C over 240 days. It indicated (i) stable pH profile (7.1-7.8), (ii) alkalinity: acidity ratio (6.1-6.8), (iii) healthy volatile fatty acid profile until organic loading rate 3.5, and (iv) biogas production (506 l/kg VS) with maximum 74% methane content. Its scale up to 85 m(3) has been successfully achieved to replace liquid petroleum gas cylinders for cooking breakfast, lunch, and dinner of about 350 individuals per day, besides use in street lighting. On the other hand, since pomegranate shells showed recalcitrance toward anaerobic digestion, it was composted successfully with and without mixing with banana peels under ambient conditions, 50 +/- 5% humidity in 15 days by transformation of C:N ratio from 22.5 to 17.0. It provided excellent germination, root ramification, shoot growth, and high chlorophyll content in leaves. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3078510]