Honey and sugar as surrogate products: an emergy evaluation

Abstract

Exploitation of natural resources has reached an unsustainable level, due to the enormous growth of world population. Industrialized intensive agriculture, in particular, demands a great quantity of natural resources. White sugar is a widespread agricultural product. Its production from sugar beet or sugarcane is very expensive from the point of view of resource exploitation and sustainability. The aim of this paper is to compare white sugar and honey as sweeteners. We compared both processes of production in terms of emergy in order to establish the environmental costs and benefits of both. Transformities of honey and sugar were calculated per unit product and per unit area of land. Honey was found to have a better environmental performance than sugar production, due to the low quantity of non-renewable resources required. The environmental loading ratio indi- cated that honey production is more environmentally friendly than sugar production. Agriculture has changed dramatically in the last fifty years. We have seen great development in food and fibre production, due to new technologies, mechanization, use of chemicals, and specialization. On the other hand, the costs have been significant. The major environmental costs are topsoil deple - tion, groundwater contamination, and the effects of massive use of fertilizers. The direct and indirect costs necessary to support this kind of agriculture make exploitation of natural resources unsustain- able. Production of food and fibres implies degradation of natural resources: water (quality and quantity), soil erosion (accelerated by ploughing), and air pollution (e.g. greenhouse gas emissions from burning fossil fuels, nitrogen fertilizer production and use, excessive ploughing). Intensive and industrial agriculture depends on non-renewable energy sources, namely fossil fuels, which implies all the negative aspects related to the use of petroleum derivatives. Sugar is a major industrialized agricultural product due to great annual demand. This widespread product is invariably derived from sugarcane or sugar beet. These crops demand many inputs (1). Table 1 shows world sugar production and consumption in 2004-2005. Since most environmental problems caused by sugar are related to mass production and consump- tion, analysis of other natural products as surrogates of sugar can be interesting. Among the alternatives, that would also help to diversify the supply of agricultural products, in some cases safeguarding local production, honey is a possible substitute for sugar as sweetener. In this paper, we evaluate the sustainability and environmental performance of honey and sugar production by an accounting methodology known as emergy evaluation. This method measures the work that nature does to support these processes, comparing them from the point of view of use of resources. It involves calculating and comparing different specific emergies. Data on these production processes is available in the literature (2, 3), and a complete emergy assessment of honey and sugar production can be found in a Chinese study (4).