Agnieszka Nowak

Food losses and waste occur throughout the food production chain, creating an urgent need for their recovery and valorization into sustainable food products. Sensory acceptance is crucial for consumer interest and market success and can be enhanced using yeast extract. However, strategies that simultaneously valorize meat and vegetable by-products into nutritionally and functionally enriched products while ensuring sensory acceptability have been scarcely investigated. This study examined whether poultry carcasses after mechanical meat separation, combined with root vegetable processing residues, could be converted into a zero-waste broth with enhanced nutritional and bioactive-related properties. The developed broth was obtained by cooking for 3 h at 122 °C under 0.2 MPa, with 2% (v/v) yeast extract added to improve umami taste. The broth was analyzed for amino acids, protein and nucleoside content, turbidity, vitamins A, K, and B-group, and antioxidant activity. The yeast-extract-enriched broth showed high levels of these vitamins, supporting EU-compliant nutrition and health claims, and demonstrated strong antioxidant activity as measured by in vitro assays. Preliminary sensory testing indicated high acceptability of the broth, likely due to the addition of yeast extract. Overall, the study demonstrates that meat and vegetable by-products can be effectively valorized into a nutritionally enriched and compositionally promising product.

Sustainable food processing and zero-waste management of by-products require the search for natural functional ingredients that can be used in finished food products. Edible mushrooms are a rich source of non-volatile bioactive compounds, but their functionality in complex food matrices remains poorly understood. The aim of the study was to compare the profiles of bioactive non-volatile compounds in Pleurotus ostreatus and Agaricus bisporus extracts obtained by the ultrasonic and combined (shaking + ultrasound) methods and to assess the possibility of using the selected extract in zero-waste broths. The content of DNA, polyphenols, nucleosides and nucleotides, and low-molecular-weight metabolites, as well as the antioxidant activity of the extracts and broths, was assessed. Significant species and technological differences in extraction efficiency were demonstrated, with A. bisporus extracts obtained using the combined method characterized by the highest content of compounds with reducing potential. Adding 2% A. bisporus extract to the broth increased the reduction potential (FRAP) and selectively altered the nucleoside and polyphenol profile, without significantly affecting key umami nucleotides. The results provide preliminary evidence suggesting that mushroom extracts could be considered as functional ingredients in zero-waste products, with the potential to enhance their bioactive properties.

Food losses and waste occur throughout the food production chain, creating an urgent need for their recovery and valorisation into sustainable food products. Sensory acceptance is crucial for consumer interest and market success and can be enhanced using yeast extract. However, strategies that simultaneously valorise meat and vegetable by-products into nutritionally and functionally enriched products while ensuring sensory acceptability have been scarcely investigated. This study examined whether poultry carcasses from mechanical meat separation, combined with root vegetable processing residues, could be converted into a zero-waste broth with enhanced nutritional and health-promoting properties. The developed broth was obtained by cooking for 3 h at 122°C under 0.2 MPa, with 2% (v/v) yeast extract was added to improve umami taste and consumer acceptance. The broth was analyzed for amino acids, protein and nucleoside content, turbidity, vitamins A, K, and B-group, and antioxidant activity. The yeast extract-enriched broth showed high levels of these vitamins, supporting EU-compliant nutrition and health claims, and demonstrated strong antioxidant activity. Consumer testing rated the broth as highly desirable, likely due to increased 5′-adenosine monophosphate enhancing umami intensity. Overall, the broth demonstrates that meat and vegetable by-products can be effectively valorised into a health-promoting, consumer-accepted product.

Lytic bacteriophages, viruses that attack and kill bacteria cells, can be used in food as biocontrol agents to prevent the growth of pathogenic bacteria. Meat is highly susceptible to bacterial growth, including pathogenic species, the control of which is crucial. Antibiotic use by breeders has resulted in bacterial resistance, which remains a huge problem; bacteriophages have emerged as an interesting alternative. In the literature, the influence of bacteriophages on common foodborne pathogens, such as Salmonella sp., Listeria monocytogenes, Campylobacter jejuni, Yersinia enterocolitica, Escherichia coli, and Shigella sp., has been described. Some phage preparations can show synergistic effects when used with other antimicrobial agents. However, data on the use of bacteriophages to inhibit the growth of meat spoilage bacteria are limited. Bacteriophages can also synthesize endolysins, which possess antimicrobial properties. Contrary to bacteriophages, which are active against only a narrow range of microorganisms (usually one bacterial species), endolysins show a broad spectrum of activity.

Numerous studies have demonstrated the efficacy of selenium compounds in preventing and treating lifestyle-related diseases such as cancer and cardiovascular disorders. The formulation of selenium-enriched supplements for humans and animals, particularly those containing selenium yeast, is highly advantageous. These products are rich in organic selenium derivatives, showing significantly higher bioavailability than inorganic forms of selenium. A particularly promising selenium analogue of sulphur-containing compounds is selenobiotin. The literature indicates that Phycomyces blakesleeanus and Escherichia coli strains can synthesise this compound. This research aimed to evaluate the effect of selenium supplementation on the biosynthesis of biotin and selenobiotin in Trichosporon cutaneum and Meyerozyma guilliermondii. The results have the potential to advance biotechnological approaches for the production of selenobiotin for various applications. A method based on affinity chromatography was used to quantify selenobiotin. The results confirmed that both yeast strains could synthesise selenobiotin in addition to biotin. In M. guilliermondii cells, selenobiotin accounted for up to 17.3% of the total biotin vitamer fraction. In comparison, in T. cutaneum cells, it accounted for up to 28.4% of the sum of biotin and its analogues. The highest levels of selenobiotin were observed in cells cultured with selenomethionine.

Poland is one of the leading apple-producing countries, both in Europe and around the world. One of the main byproducts of apple processing is pomace, which can account for 20–35% of the harvested apples. Pomace is a potential source of many valuable bioactive components and can also serve as a food ingredient, either directly or indirectly (after bioconversion with fodder yeast). This study aimed to evaluate the possibility of converting polysaccharides contained in apple pomace to yeast biomass. Meyerozyma guilliermondii and Scheffersomyces stipitis yeasts were grown in a medium prepared by pretreatment of the raw material with water or 2% sulphuric acid at 120 °C. Subsequently, enzymatic hydrolysis was performed using a Cellic CTec2 preparation at 30 °C or 50 °C. The resulting hydrolysates were enriched with ammonium salts, and shaken yeast cultures were incubated at 30 °C for 72 h. Based on the results, it can be concluded that acid pretreatment of apple pomace is more effective than water pretreatment under the same time and temperature conditions. The Meyerozyma guilliermondii strain grows in apple pomace hydrolysates more efficiently (16.29 g/L) than Scheffersomyces stipitis cells do (14.63 g/L).

Phytoremediation is one of the effective technologies for removing pollutants from the aquatic environment. Toxic compounds such as chlorpyrifos can affect the physiological processes of aquatic plants, causing secondary oxidative stress in plant tissues. Macrophytes, like other organisms inhabiting the contaminated ecosystem, have developed a system of defense mechanisms, thanks to which plants can still exist in their natural ecosystem. Our research is a summary of the previously presented results of the effectiveness of purifying contaminated water with chlorpyrifos in the phytoremediation process and the second type of phytoremediation supported by microorganisms, which intensify the process of removing contaminants from the environment. This research concerned changes in nonenzymatic and enzymatic antioxidants in Canadian seaweed, needle spikerush and water mint caused by chlorpyrifos. The research determines changes in the total concentration of polyphenols, flavonoids and dyes (chlorophyll A, chlorophyll B, anthocyanins and carotenoids) as well as differences in the activity of guaiacol peroxidase and glutathione S-transferase. The analysis of the results showed an increase in the content of polyphenols and flavonoids. The reverse trend was observed in the case of the pigment content. The appearance of chlorpyrifos in the environment caused an increase in the activity of the examined enzymes. The process involving microorganisms that were obtained from places contaminated with pesticide proved to be more effective. This shows the cooperation of species living in an investigated ecosystem.

This study evaluates the effects of polyphenolic extract of Cistus incanus, lycopene dye from tomatoes, and betanin dye from red beet on selected parameters of model meat products with reduced nitrate contents. The polyphenolic composition and activity of the C. incanus extract was analyzed, revealing the presence of elagotannins, flavanols, and glycosylated flavanols. We studied the effects of the extract and dyes as well as of mixtures of the extract and dyes on the growth of bacteria characteristic of the meat environment: E. coli, S. enterica, P. fragi, L. monocytogenes, B. thermosphacta, and L. sakei. We studied the effects of the extract and dyes on the lipid oxidation, color, and microbiological quality of pork sausages with reduced nitrate content over 28 days of storage. During storage, the amounts of malon dialdehyde reduced, which indicates that the extract and dyes exhibited antioxidant activity and slowed lipid oxidation in the sausages. An increase in red color was also observed in the sausages with natural additives, despite their decreased nitrate content. It was found that the C. incanus extract combined with coloring agents positively influenced the selected parameters of the analyzed pork sausages.