Evaluation of cradle to gate environmental impact of frozen green bean production by means of life cycle assessment

The main objective of this study is to assess the impact of frozen green bean production and processing. The analysis and relative information collected regards a medium industry located in the south of Marche region (Italy) and the whole production system, from field to industry, is in a range of about 100 km between Marche and Abruzzo regions. The aim of this study is to assess the impact of 1 kg of frozen green bean for two different cultivation protocols for herbicides and pesticides application in order to assess the possible advantages due to shifting to different field treatments. The baseline scenario (A) considers the application of two herbicides (Pendimethalin and Linuron) and two pesticides (Altacor and Azoxystrobin), the alternative scenario (B) considers one herbicides application (Clomazone) and two pesticides (Emamectine and Azoxystrobin). The analysis has been conducted following ISO 14040 and 14044 on Life Cycle Assessment (LCA) and Product Category Rules for arable crops v. 2.0. LCI (Life Cycle Inventory) and LCIA (Life Cycle Impact Assessment) phase have been performed using LCA software SimaPro® v. 8.2.3.0 with updated databases. The most used databases for this study are Ecoinvent 3 and Agri-footprint, LCI data have been collected through interviews, consulting official documents and company management programs. The system boundaries considered includes crop production, transport to industry plant and industry processing and all the data are referred to 2014 crop season. Crop production LCI considers seeds, fertilizers, pesticides, field activities, yield and relative emissions. Transportations covers distances and payload with empty return. Industry phase considers transformation efficiency, energy, fuels, water. The function of the production chain is to provide frozen green bean, no coproduct or by-product were produced. Residues and product losses from industry processing are managed by anaerobic digestion as waste. Plastics and other wastes from field and industry has been treated by landfill. Data regarding field phase were collected by interviews and consulting official management documents from 43 farms. Data regarding industrial phase have been gathered from automated management systems hardware/software AS/400 (IBM). The LCIA results for 1 kg of frozen green been show an impact of about 0.7 kg of CO2 eq for GWP, 1.9E-4 kg of C2H4 eq kg for PCOP, 3.5E-3 kg of SO2 eq for AP and 1.7E-3 kg of PO43- for EP. The analysis conducted comparing two different solutions of plant protection and herbicides application shows how solution A has a lower impact on ADP, ADP fossil, GWP 100yr, ODP, MEP, PCOP, AP and EP from 0.04% to 11% about. On the other hand, solution B has a lower impact on HTP, FEP, MEP and TEP between 4 and 40%. The analysis conducted shows the impact of frozen green been at industry level representative of medium size processing plant with average technology. The only information available in literature are limited to open field production impact assessment of raw green bean without any kind of industry transformation. . Simply replacing herbicide treatment and one pesticide application, for preventing weed and pest resistance, there is a consistent reduction of impact on different categories for ecotoxicity group without increasing too much the impact on other categories considered. The only exception can be found for ADP category in which the impact of alternative scenario (B) is higher than baseline (A). The reason lies in the lower active ingredient concentration and higher amount of commercial product used for solution B. From the analysis remains evident the contribution on ADP fossil, GWP and ODP due to energy used in industrial phase. On the other side field phase contributes more on ADP, HTP, FEP, AP and EP.