# Pallet Picking Strategy in Food Collecting Center
## 2 Literature Review  
As introduced in the prior paragraph, the sustainability is a wide concept that undoubtedly encompasses economic and environmental issues, such as polluting reduction and costs reduction, to say a few [17; 18]. These two facets are squarely interrelated each other, and reducing environmental impacts means reducing costs for the ecosystem where organizations survive, so in turn, for single enterprises [19]. According to [PERSON] et al. in [20] a considerable number of studies dealing with sustainability issues in logistics have been introduced, and several models have been developed in order to minimizing the impact under environmental and economic perspective. Indeed, scientific studies show that an improvement of environmental performances leads to an improvement of products and services quality which, in turn, improves cost performances. In this context, [PERSON] et al. in [21] provide a mathematical model to select the shortest path allowing to reduce environmental harmful emission in the field of food supply chain. A model based on Artificial Neural Network is developed in order to predict the emissions and evaluate how the cost related to green practices positively impacts on competitiveness in workplaces [22]. A very similar methodology is adopted by [PERSON] and [PERSON] in order to analysis and evaluate the relationship between the adoption of green supply chain practices and economic performance [23]. In search for solutions to the sustainability challenge, researcher and practitioners have explored and established the potential for managerial systems to drive sustainable organizational performance [24]. According to [PERSON] et al. in [25] a first class of models is based on the well-known Economic Order Quantity (EOQ) strategy that aims to minimize the inventory and ordering costs as developed in 1913. Later, [PERSON] and [PERSON] in [26] modified the EOQ model with the purpose of evaluating transportation and other logistic costs separately. Several models followed the work of [PERSON] and [PERSON] [27; 28], until a new inventory model that has been developed, namely the Sustainable Order Quantity (SOQ), which considers both economic and socio-environmental costs [29]. Models mainly differ in the function adopted for calculating transportation costs and the solutions thought lowering them. An increasing number of sustainable solutions make possible the minimization of logistic costs (inventory, transport costs) and environmental impact both, but most research is rather limited to studying the environmental impact of warehousing and inventory management from an outdoor perspective (outbound logistics) [18]. [PERSON] et al. in [30] identified five decisional areas within the warehouse design, as shown in Figure 1 and reported, as follows:  
1. Overall structure
2. Department layout
3. Operation Strategy Selection
4. Equipment Selection
5. Sizing and Dimensioning  
In particular, the Department layout (II) concerns the configuration of the aisles and the retrieval area. Instead, the Operation Selection Strategy (III) is related to the way the warehouse works in terms of layout and order picking. Under this study, both components play an important role in optimizing the material handling strategy, and in turn in affecting the returning value in terms of environmental and economic performance [19]. In the last decades, most researches have concentered on order picking strategy, in particular examining the energy usage in the forklift material handling, taking into account factors such as the  
Figure 1: Warehouse Design. pallet lift height and the routing of the non-road vehicles within the warehouse [31]. The choice of the Material Handling Equipment (MHE) characterized by low energy consumption is not the only strategy that allows for minimizing the environmental impact of the warehousing activities [32].