4 Presentations

• 
  02:00 PM - 02:25 PM

  Two-Echelon Capacitated Location-Routing Problem for the Organic Food Sector

  • Daniel Ocampo-Giraldo, presenter, ESG-UQÀM
  • Ana María Anaya Arenas, ESG - UQAM
  • Janosch Ortmann, UQAM
  • Walid Klibi, CESIT

  In this presentation we introduce the Collaborative Location-Routing Problem for organic food distribution within a nonprofit organization that coordinates multiple producers and food banks to transport small, perishable shipments under strict service-level agreements. We propose two mixed-integer formulations: one using continuous-time synchronization and the other leveraging a time-expanded network. Both formulations capture key decisions on choosing transfer hubs, assigning vehicles, and respecting capacity and time constraints. Due to the complexity of these formulations, a tailored matheuristic is introduced. First, an interval-based network relaxation generates lower bounds by reducing time granularity. Next, feasibility checks identify valid transfers and routing schedules. Finally, a constructive heuristic refines routes and assigns commodities, yielding high-quality upper bounds within feasible computation times. Extensive experiments, based on real data from an organic food cluster, demonstrate the benefits of resource pooling and enabling intermediate transfers, resulting in reduced routing distances, fewer vehicle requirements, and stricter adherence to freshness constraints. Beyond efficiency gains, the framework supports more sustainable food logistics by lowering emissions and costs, particularly relevant for nonprofits and small producers. Overall, this approach highlights the value of synchronized, hub-based solutions in regional perishable supply chains.

• 
  02:25 PM - 02:50 PM

  Meta-Heuristic Solution Algorithm for the Organic Food Collaborative Location and Routing Problem

  • Daniel Ocampo-Giraldo, presenter, ESG-UQÀM
  • Ana María Anaya Arenas, ESG - UQAM
  • Janosch Ortmann, UQAM

  In this presentation, we introduce a meta-heuristic algorithm to solve the Collaborative Location-Routing Problem for organic food distribution. This problem arises in the context of a nonprofit organization that coordinates multiple producers and food banks to transport perishable goods under strict service-level agreements. We propose a multi-phase algorithm to determine the location of transshipment points (hubs) and the design of vehicle routes while minimizing the total cost.

  The first phase addresses the location and transshipment decisions. We propose an auxiliary mixed-integer programming model that approximates the routing cost and determines the number of hubs and the commodities transshipped at each hub location. The second phase takes the location decisions as input and generates a feasible solution using a greedy construction heuristic. Finally, we apply an adaptive large neighborhood search, adapted from the pickup-and-delivery problem with transshipments, to further refine the solution.

• 
  02:50 PM - 03:15 PM

  A neighborhood search-based matheuristic for poultry production-distribution optimization.

  • Samuel Gbeya, presenter,
  • Maryam Darvish, Université Laval
  • Jacques Renaud, Université Laval, CIRRELT
  • Leandro C. Coelho, Université Laval

  This study describes models and solves a production and distribution planning problem in the poultry supply chain. Production planning comprises the number of chicks to be raised on each farm, the start time and the duration of their breeding. The delivery schedule focuses on the timing and the number of chickens to be delivered to each slaughterhouse in each period, considering the transportation cost and the allocations of the quota. This paper aims to develop efficient production and delivery schedules that reduce the total production and distribution costs while meeting the numerous constraints of the industry. We first model the problem as a mixed-integer linear programming formulation and propose a neighborhood search-based matheuristic to solve real-size instances of the problem. The computational results on instances generated based on a Qu{\'e}bec poultry producer prove the efficiency of the proposed algorithm.

• 
  03:15 PM - 03:40 PM

  Minimising food waste through harvest and side-stream valorisation - Optimisation for sustainable agri-food supply chains

  • Marloes Remijnse, Technical University of Eindhoven
  • Sonja Ursula Katharina Rohmer, presenter, HEC Montréal
  • Ahmadreza Marandi, Technical University of Eindhoven
  • Tom van Woensel, Technical University of Eindhoven

  The potential of reuse and valorisation in order to reduce waste streams and recover resources in the chain is increasingly recognised. Despite this recognition, the potential of (edible) side streams, such as unharvested crop parts and vegetable peels, often remains overlooked and under utilised within the food and agricultural sector. This research develops a mixed-integer optimisation model to support decision-makers in determining an optimal product portfolio and processing configuration focused on side-stream valorisation strategies within food processing facilities. Considering both economic and environmental impacts, the model is solved for two key performance indicators, namely total profit and exergy loss. Examining potential trade-offs between these two objectives, the research is applied to a real-life case study from a carrot processing company and explores several scenarios and case settings to investigate the impact of various factors on the potential of side-stream valorisation. The findings from this analysis show that side-stream valorisation seems to be generally well aligned with profit maximisation, while it is not always beneficial from an environmental impact perspective.