Poly(lactic acid) (PLA) has great potential in the plastic packaging industry due to its biodegradability, versatility, andgood performance. PLA compounding with different biobased materials to enhance the flexibility and biodegradability ofPLA-based packaging materials has attracted growing attention. Fungal biomass (FB), as a biological and eco-friendlyby-product stream from fermentation processes, can be a valuable blending component in PLA-based biocomposites.Therefore, in this study, 10 and 20 wt% of fungal biomass (FB), defatted fungal biomass (DFB), and fungal cell wall(FCW), as promising biobased materials, were added to PLA plasticised with 10 wt% triethyl citrate (TEC) to fabricatebiocomposites using the melt compounding technique. Our research focused on how the addition of fungal biomass andits fractions affected the mechanical and thermal properties, as well as the structure of PLA-based blends. These additionsdid not increase the strength of the biocomposites, but they did improve flexibility compared to regular plasticised PLA.The crystallisation of plasticised PLA samples blended with FB and DFB began at lower temperatures than neat PLA,plasticised PLA, and plasticised PLA blended with FCW. The addition of fungal biomass and its fractions, particularlyat 20 wt%, accelerated the biodegradation of PLA-based composites. Neat PLA and plasticised PLA degraded slowly insoil and retained most of their mass, whereas PLA-based blends containing FB and its fractions degraded significantlyfaster. It can be concluded that fungal biomass is a promising candidate for improving the flexibility of PLA blends andfacilitating their biodegradation in a natural soil environment.

The global demand for sustainable protein sources—driven by population growth, climate change, and increasing pressure on conventional agriculture—has intensified the search for innovative, eco-friendly production methods. Post-distillation wine lees (vinasse) remains a largely underutilized byproduct of the wine and distillery industries. For every liter of ethanol produced, approximately 9–14 liters of vinasse are generated, creating a pressing need to manage trillions of liters annually. Due to its composition—particularly its high polyphenolic content and chemical oxygen demand—vinasse poses significant environmental and public health risks if not properly treated. This study presents a novel bioconversion strategy to valorize vinasse by cultivating protein-rich fungal biomass through submerged fermentation, using edible Ascomycetes and Zygomycetes filamentous fungi. The proposed biorefinery approach not only mitigates waste management challenges but also offers a scalable and sustainable pathway for alternative protein production. By converting a problematic effluent into a valuable resource, this bioprocess contributes to the development of circular, climate-smart food.

The wine industry generates significant amounts of white grape pomace (WGP), a lignocellulosic byproduct with untapped potential for valorisation. This study presents an integrated biorefinery approach to maximize the utilization of WGP through a combination of hydrothermal and organosolv treatments, followed by solid state fermentation (SSF). Hydrothermal pretreatment was optimized to maximize sugar extraction, achieving up to 80.94 g L⁻¹ of reducing sugars, which can serve as a substrate for microalgae cultivation. Organosolv treatment enabled the selective recovery of polyphenols and lignin, with the highest polyphenol yield (2.27 g kg⁻¹ DW) obtained at 150 °C and a lignin yield of 34.72 % at 200 °C. The remaining solid fractions were subjected to SSF using Aspergillus oryzae, Neurospora intermedia, and Rhizopus oryzae, leading to a significant increase in protein content, with A. oryzae achieving a protein content of 17.6 % on dry weight basis. This multi-step integrated approach demonstrates a scalable and sustainable strategy for converting WGP into multiple high-value bioproducts, promoting circular economy principles in the food sector.

The increasing global population and rising environmental and nutritional demands require sustainable, alternative protein sources. This study explores the biovalorization of grape marc, a by-product of winery and distillery industries, as cultivation medium for edible filamentous fungi to produce protein-rich biomass for food applications. Three fungal strains, Neurospora intermedia, Aspergillus oryzae, and Rhizopus oryzae, were cultivated at three scales: shake flasks, bench-scale (4.5 L), and demo-scale (1300 L) bubble column reactors. Hydrothermal pretreatment (121 °C, 20 min) was applied to grape marc (GM) prior to fermentation under varying GM concentrations (2–8 % w/v), pH (3.88–6), cultivation times (48–72 h), and supplementation (vitamins, trace metals, yeast extract). The fungal biomass was analyzed for physicochemical properties, crude protein and fat, amino acid and fatty acid profiles, minerals, and polyphenols. The fungal biomass yields reached up to 4.4 g dry weight/L, with crude protein contents up to 60 % dry weight, notably with N. intermedia. Fungal biomass exhibited a complete essential amino acid profile, with high leucine and lysine levels, along with favorable fatty acid, minerals and polyphenols. This study demonstrates the feasibility of producing sustainable, protein-rich fungal biomass from GM, offering a valuable solution for food applications within a circular bioeconomy.

Filamentous fungi are an amazing group of microorganisms able to both degrade and produce a plethora of different compounds. Many fungi have rather modest nutritional requirements, making them very interesting for biotechnological applications, with applications in both submerged and solid-state fermentation. Applications include agriculture, food, and feed, pharmaceutical, pulp and paper, textile industries, as well as a potential for waste valorization. Some of the current and potential products include: ethanol, citric acid, gluconic acid, itaconic acid, lactic acid, fumaric acid, and the fungal biomass as a food or feed, as well as more specific compounds such as enzymes.

Fungal biomass (FB), a by-product of the fermentation processes produced in large volumes, is a promising biomaterial that can be incorporated into poly(lactic acid) (PLA) to develop enhanced biocomposites that fully comply with the biobased circular economy concept. The PLA/FB composites, with the addition of triethyl citrate (TEC) as a biobased plasticizer, were fabricated by a microcompounder at 150 °C followed by injection molding. The effects of FB (10 and 20 wt %) and TEC (5, 10, and 15 wt %) contents on the mechanical, thermal and surface properties of the biocomposites were analyzed by several techniques. The PLA/FB/TEC composites showed a rough surface in their fracture section. A progressive decrease in tensile strength and Young’s modulus was observed with increasing FB and TEC, while elongation at break and impact strength started to increase. The neat PLA and biocomposite containing 10% FB and 15% TEC exhibited the lowest (3.84%) and highest (224%) elongation at break, respectively. For all blends containing FB, the glass transition, crystallization and melting temperatures were shifted toward lower values compared to the neat PLA. The incorporation of FB to PLA thus offers the possibility to overcome one of the main drawbacks of PLA, which is brittleness.

Oyster mushroom (OM) cultivation generates residue that needs to be managed; otherwise, it will be converted into waste. One of the substrates for OM cultivation is the food industry by-product, e.g., a mixture of the brewer’s spent grain (BSG) and wheat bran. This study assesses the OM cultivation residue’s physical and nutritional characteristics as a potential upcycled food ingredient and also considers developing bread from this cultivation residue. The OM was cultivated in a mixture of 55% BSG and 45% wheat bran. After the OM harvest, the cultivation residue (mixture of BSG, wheat bran and mycelium) had a lighter colour and a pleasant aroma compared to the initial substrate. It contained protein (10.8%) and had high niacin (42.4 mg/100 g), fibre (59.2%) and beta-glucan (6.6%). Thiamine, riboflavin and pyridoxine were also present in the cultivation residue. The bread was developed from 50% cultivation residue and 50% wheat flour, and its scores for darkness, dryness, sponginess, sour taste, bitter aftertaste, and aromatic aroma differed from white bread (p-value < 0.05). However, its overall acceptability and liking scores were not significantly different from white bread (p-value > 0.05). Therefore, this OM cultivation residue can be used as a nutritious ingredient; nevertheless, product development should be further explored.

Bread residues represent a significant fraction of retail food wastes, becoming a severe environmental challenge and an economic loss for the food sector. They are, however, an attractive resource for bioconversion into value-added products. In this study, the edible filamentous fungi Neurospora intermedia and Aspergillus oryzae were employed for the production of bioethanol and high-protein biomass by cultivation on enzymatically liquefied bread-waste medium at 150 g/L solids. The fermentation of hydrolysate by N. intermedia resulted in the ethanol titer of 32.2 g/L and biomass yield of 19.2 g/L with ca. 45% protein. However, the fermentation ended with a considerable amount of residual fermentable sugars; therefore, the liquid medium after the first fermentation was distilled and fermented again by two fungal strains (N. intermedia and A. oryzae). The fermentations resulted in the production of additional ethanol and biomass. A. oryzae showed better performance in the production of biomass, while the other strain yielded more ethanol. The final products’ yield ranged 0.29–0.32 g EtOH/g and 0.20–0.22 g biomass/g bread waste depending on the strain used in the second fermentation. The study shows that valorization of bread residuals by fungi is a promising option for the production of biofuels and foodstuff within the circular bioeconomy approach. 

A novel approach of utilizing unsold bread at bakeries as a substrate for the fermentative production of a fungal food product have been developed. Techno-economic feasibility of implementing on-site solid-state fermentation in small-scale bakeries in Sweden to recover 10 kg/day surplus bread using the edible fungus Neurospora intermedia was investigated. Different inoculation to substrate ratios were compared, where 24% of fermented solids to inoculate the next batch presented the best fermentation-benefit ratio. Total capital cost was at its maximum €12,600 that can process 70 tons bread (10 kg/day) in its 20-years lifetime to produce 63 tons of product. Operational costs were dominated by labour cost (53%). Outcomes indicate that the process implementation is economically feasible with an annual net profit of €62,000, rate of return on investment of 18.5%, with a payback-period of 4 years at a discount rate of 7%. According to sensitivity analysis, product-selling price and process bread capacity were critical to the process's economics. Increasing the capacity to 100 kg/day resulted in a substantial increase in net profit value of €5,700,000 compared to the base case scenario. Implementation of this process cast insights on techno-economic performance of a sustainable treatment for surplus bread at bakery-level.