Food waste processing biodiesel production

Animal fats (mainly lard, taUow, and chicken), insects, soapstocks, or microorganisms for oil production (eg, microbial oil from yeast, microalgae, molds, bacteria, and cyanobacteria) were compared as cheap sources of biomass for renewable biofuel production by the author and her coworkers in 2014 and can be consulted (Pinzi et al., 2014). Biodiesel production from microbial oil, food waste, or algae, among others, as well as challenging techniques for sustainable processing, is covered later in this book. 

The raw materials that wiU be used for the production of SCO-derived biodiesel do not compete with food production. In this way, cultivation of land for food production as well as industrial food processes could coincide with biodiesel production by utilizing residues and agro-industrial wastes. 

Bio-fuels should be not in competition vith food. Therefore, new technologies need to be developed to efficiently convert cellulosic, fiber or wood-based, waste biomass into fermentable sugars. Similarly, to make biodiesel competitive as a transport fuel, efforts should be directed to diversify the use of raw materials and to improve the processes while making them more economic by developing added-value uses for by-products such as glycerol. Catalysis plays a critical role in achieving these objectives [9]. 

The author and colleagues have already written a revision on the valorization processes for waste cooking or frying oils (WFO) (Pinzi et al., 2014). Nevertheless, they deserve a special mention in this section due to its high quantity (15 million tons per year), easy availability and low-cost transformation methods (Lopresto et al., 2015). The conversion of all available WFO into biodiesel would cover the world demand for biofuels, increasing production sustainability, eliminating a harmful waste from the environment and overcoming the competition with food markets. 

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