*Article* **The Use of Life Cycle Assessment in the Support of the Development of Fungal Food Products from Surplus Bread**

**Pedro Brancoli \* , Rebecca Gmoser , Mohammad J. Taherzadeh and Kim Bolton**

Swedish Centre for Resource Recovery, University of Borås, 50190 Borås, Sweden; rebecca.gmoser@hb.se (R.G.); mohammad.taherzadeh@hb.se (M.J.T.); kim.bolton@hb.se (K.B.)

**\*** Correspondence: pedro.brancoli@hb.se

**Abstract:** The use of food waste as feedstock in the manufacture of high-value products is a promising avenue to contribute to circular economy. Considering that the majority of environmental impacts of products are determined in the early phases of product development, it is crucial to integrate life cycle assessment during these phases. This study integrates environmental considerations in the development of solid-state fermentation based on the cultivation of *N. intermedia* for the production of a fungal food product using surplus bread as a substrate. The product can be sold as a readyto-eat meal to reduce waste while generating additional income. Four inoculation scenarios were proposed, based on the use of bread, molasses, and glucose as substrate, and one scenario based on backslopping. The environmental performance was assessed, and the quality of the fungal product was evaluated in terms of morphology and protein content. The protein content of the fungal food product was similar in all scenarios, varying from 25% to 29%. The scenario based on backslopping showed the lowest environmental impacts while maintaining high protein content. The results show that the inoculum production and the solid-state fermentation are the two environmental hotspots and should be in focus when optimizing the process.

**Keywords:** life cycle assessment; *Neurospora intermedia*; bread; process development
