Loriana Casalino

Poultry feather waste, one of the major by-products of the poultry industry, represents an underutilized protein-rich biomass with significant potential for sustainable valorization within the circular bioeconomy. This narrative review examines recent advances in the use of poultry feathers as a renewable source of keratin for the development of keratin-based biomaterials. A structured literature search of original research articles published between 2015 and 2026 resulted in a final primary evidence map of 524 records, which was used to evaluate current knowledge on poultry feather management, keratin structure and properties, extraction technologies, and the development of feather-derived biomaterials. The reviewed literature indicates that keratin recovery can convert feather waste into higher-value materials, although its environmental performance depends on the extraction route, energy and chemical requirements, and comparison with established feather-management pathways. Recent advances highlight the potential of feather-derived keratin for biodegradable films, composites, hydrogels, coatings, packaging, biomedical, agricultural, and environmental applications. However, challenges remain regarding scalable extraction technologies, material performance, process standardization, and industrial implementation. This review provides a comprehensive overview of current research and identifies future directions for integrating poultry feather valorization into circular bioeconomy strategies, supporting resource efficiency and the development of sustainable bio-based materials.

Cilentana goat cheese is a traditional dairy product made from raw goat’s milk in the Cilento region (Southern Italy). This study investigated microbiological, physicochemical, and lipid changes occurring during cheese-making and 90 days of ripening. Four independent batches were produced from raw Cilentana goat milk and sampled as milk, curd, and cheeses at 0, 30, 60, and 90 days for microbiological, physicochemical, fatty acid, lipolysis, oxidative stability, and color analyses. Overall, ripening promoted the establishment of a dominant lactic acid bacteria population, with mesophilic lactococci and lactobacilli reaching approximately 8 and 7.5 Log CFU/g, respectively, while E. coli and coagulase-positive staphylococci progressively declined below detectable or regulatory levels by day 60. Salmonella spp. and Listeria monocytogenes were never detected, although coliforms persisted throughout ripening, highlighting the need for improved raw milk hygiene. From a chemical perspective, lipolysis progressed during ripening, with free fatty acids (FFAs) significantly increasing after 90 days, while malondialdehyde levels remained low and unchanged, indicating limited lipid oxidation. The fatty acid profile and nutritional quality indices remained stable throughout ripening. In conclusion, the data collected provided a better characterization of this traditional cheese and can be used for broadening knowledge of raw goat’s milk cheeses.

Aim. The aim of this study was to evaluate the effect of film consisting of poly (butylene succinate-co-adipate) (PBSA) with keratin extracted from chicken feathers on the shelf-life of refrigerated Atlantic salmon (Salmo salar).Methods. A total of three groups of salmon samples were compared: untreated salmon (ST, without film application), salmon in contact with PBSA film (CTR), and with a PBSA film containing 5% keratin (TRT) stored at 4°C for 7 days. The samples were analyzed at days 0, 2, 5, and 7 for microbiological (total viable count at 30°C and 7°C, Pseudomonas spp., Enterobacteriaceae, Brochothrix thermosphacta, Enterococci, E. coli, and coagulase-positive staphylococci) and physicochemical (pH; water activity; thiobarbituric acid reactive substances, TBA test; total volatile basic nitrogen, TVB-N; trimethylamine, TMA; colour parameters, CIEL*a*b*) characteristics. Additionally, instrumental sensory analysis using an electronic nose (PEN3) was performed to correlate the response of selected sensors with chemical spoilage indicators (Pearson’s correlation). Differences between samples and in the sampling time were evaluated by two-ways analysis of variance (ANOVA; p< 0.05 and p< 0.01). All analyses were performed in triplicate.Results. Overall, the salmon TRT showed better quality preservation compared with ST and CTR samples throughout the entire experimental period. In line with current literature, CTR displayed a mild, inherent antimicrobial effect compared to ST, notably slowing down microbial growth by day 5 across key indicators (total aerobic counts, Pseudomonas spp., Enterococci, and maintaining E. coli below detection limits). The TRT maintained a protective trend, achieving a ~0.5 Log (CFU/g) reduction at day 5 against both total viable counts and Pseudomonas spp. compared to the ST. During storage, pH decreased in all groups, with TRT showing the lowest values, whereas water activity remained high and stable across all samples. Color analysis also showed that TRT preserved redness and chroma compared with ST and CTR. Moreover, TRT exhibited the lowest TBARS (0.028), TVB-N (21.31) and TMA (2.21) values, compared with both the ST and CTR samples at the end of the storage. This suggests a protective effect of keratin against lipid oxidation and the accumulation of volatile nitrogen compounds, whose functional groups of keratin may interact with oxidation products, volatile compounds, and the protein matrix of salmon. The electronic nose showed an increase in spoilage-related volatile compounds during storage, with sensors S2, S6, S7, S8 and S9 responses showing a significant positive correlation with TVB-N (p < 0.05). At the end of storage, TRT samples exhibited lower sensor responses than ST and CTR, further supporting the protective effect of the keratin-containing film.Conclusions. The study showed that neat PBSA contributed to limiting microbial growth, whereas keratin incorporation enhanced the preservation of colour and reduced lipid oxidation and the accumulation of volatile nitrogen compounds. These complementary effects resulted in the keratin-containing PBSA film providing the best overall preservation of salmon quality during refrigerated storage, as also supported by the lower electronic-nose responses associated with spoilage. Further studies are required to confirm these findings and clarify the contribution of keratin to the overall preservative effect.

Phospholipids (PLs) are a group of biomolecules found in the milk fat globule membranes (MFGMs). Recently, MFGM phospholipids have attracted increasing amounts of attention due to their unique composition, stability, and potential health benefits, including protective effects against Alzheimer’s disease, hypercholesterolemia, and certain types of cancer. Although buffalo milk is the second most commonly produced milk and has high nutritional value, few studies have focused on the properties of buffalo MFGM. This study investigates the PLs composition of buffalo milk and related dairy by-products (whey and buttermilk). Milk and whey were collected from two dairy farms (A—small and B—big) to produce mozzarella buffalo cheese (high-pasteurization milk for GDO production and low for local); while buttermilk was obtained from a butter-making farm. Phospholipids were purified by a solid-phase extraction method and then identified by high-performance liquid chromatography with an evaporative light-scattering detector (HPLC/ELSD). Five classes of phospholipids [phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), phosphatidylserine (PS), and sphingomyelin (SM)] were identified. The thermal process of milk did not significantly affect the PLs milk. However, local whey showed a higher concentration of total PLs than GDO, which was mainly represented by PE followed by PC content. Farm A exhibited higher PL content than B, particularly with a greater concentration of SM. Buttermilk showed the lowest PLs content. These findings offer valuable insights for the dairy industry and related applications, contributing to the valorization of buffalo dairy products.