Vulnerable vegetables and efficient fishers: A study of primary production food losses and waste in Ireland.

From 2022, the European Union Waste Framework Directive (WFD) requires member states to report annual food waste from each food supply chain stage. Comprehensive food losses and waste (FLW) data can be challenging to obtain for the primary production stage, i.e., farming and fishing. However, this information is vital in developing FLW mitigation actions appropriate to each country. This study describes the nature and extent of FLW from primary production in Ireland, using methods approved for WFD reporting. Causes of FLW and FLW as a proportion of total production were determined through interviews with Irish primary production stakeholders and using national FLW data where available. The FLW was presented for each primary production sector - animal husbandry, horticulture, tillage, aquaculture, and fisheries. The total annual FLW from Irish primary production was 189,508 tonnes. The main FLW sources were vegetable production (122,398 tonnes), meat production (41,726 tonnes), and tillage (12,502 tonnes). The activities associated with high FLW did not reflect the quantity of food from those activities, e.g., dairy generated the greatest quantity of animal husbandry produce (89%) but only 7% of animal husbandry FLW. The main causes of FLW in Irish primary production were pests, disease, injuries, and production stress (37%), followed by un-harvestable or un-saleable produce, 24% and 21%, respectively. The majority of FLW described in this study (63%) is considered food loss, meaning mitigation efforts should focus on this rather than food waste. These results also clearly indicate priority areas for mitigation action, e.g., horticulture. This research suggests mitigation actions that improve long-term farm sustainability, e.g., improve soil health, reduce FLW and contribute to food production potential in fisheries and aquaculture.

Comparison of phosphorus recovery from incinerated sewage sludge ash (ISSA) and pyrolysed sewage sludge char (PSSC).

This research compares and contrasts the physical and chemical characteristics of incinerator sewage sludge ash (ISSA) and pyrolysis sewage sludge char (PSSC) for the purposes of recovering phosphorus as a P-rich fertiliser. Interest in P recovery from PSSC is likely to increase as pyrolysis is becoming viewed as a more economical method of sewage sludge thermal treatment compared to incineration. The P contents of ISSA and PSSC are 7.2-7.5% and 5.6%, respectively. Relative to the sludge, P concentrations are increased about 8-fold in ISSA, compared to roughly 3-fold in PSSC. Both PSSC and ISSA contain whitlockite, an unusual form of calcium phosphate, with PSSC containing more whitlockite than ISSA. Acid leaching experiments indicate that a liquid/solid ratio of 10 with 30min contact time is optimal to release PO4-P into leachate for both ISSA and PSSC. The proportion of P extracted from PSSC is higher due to its higher whitlockite content. Heavy metals are less soluble from PSSC because they are more strongly incorporated in the particles. The results suggest there is potential for the development of a process to recover P from PSSC.