Autochthonous single (Ent+) or multiple (m-Ent+) enterocin-producing strains of dairy enterococci show promise for use as bioprotective adjunct cultures in traditional cheese technologies, provided they possess no pathogenic traits. This study evaluated safety, decarboxylase activity, and enzymatic (API ZYM) activity profiles of nine Ent+ or m-Ent+ Greek cheese isolates previously assigned to four distinct E. faecium (represented by the isolates KE64 (entA), GL31 (entA), KE82 (entA-entB-entP) and KE77 (entA-entB-entP-bac31)) and two E. durans (represented by the isolates KE100 (entP) and KE108 (entP-bac31-cyl)) strain genotypes. No strain was β-hemolytic or harbored vanA and vanB or the virulence genes agg, ace, espA, IS16, hyl, or gelE. All strains were of moderate to high sensitivity to ampicillin, ciprofloxacin, chloramphenicol, erythromycin, gentamicin, penicillin, tetracycline, and vancomycin, except for the E. faecium KE64 and KE82 strains, which were resistant to erythromycin and penicillin. All cheese strains showed moderate to strong esterase-lipase and aminopeptidase activities and formed tyramine, but none formed histamine in vitro. In conclusion, all Ent+ or m-Ent+ strain genotypes of the E. faecium/durans group, except for the cyl-positive E. durans KE108, were safe for use as adjunct cultures in traditional Greek cheeses. Further in situ biotechnological evaluations of the strains in real cheese-making trials are required.

Τhe present study was carried out to evaluate wheat bread of three different flour compositions prepared by replacing water with untreated cheese whey (WCB). Bread prepared with water was taken as the control (CB). All breads were stored at 24 ± 1 °C for up to 6 days. Microbiological, physicochemical, and sensory analyses were determined as a function of storage time. WCB had lower total viable counts (TVC) (3.81 log cfu/g for CB and 2.78 log cfu/g for WCB on day 2 of storage) and showed delayed mold growth by 1 day (day 4 for CB and day 5 for WCB). WCB also had lower pH (5.91 for CB and 5.71 for WCB on day 0), higher titratable acidity values (TTA) (2.5–5.2 mL NaOH/10 g for CB and 4.5–6.8 mL NaOH/ 10 g for WCB), and higher protein content (PC) (PC 7.68% for CB and 8.88% for WCB). WCB was characterized by a more intense flavor, reduced hardness but similar cohesiveness, springiness, and adhesiveness compared to CB. Based primarily on sensory (appearance/mold formation) data, the shelf life of WCB was 4–5 days compared to 3–4 days for CB stored at 24 ± 1 °C. The proposed use of whey in bread preparation contributes decisively to the environmentally friendly management of whey.

The performance of a mixed thermophilic and mesophilic starter culture consisting of Streptococcus thermophilus ST1 and the Greek indigenous nisin-A-producing Lactococcus lactis subsp. cremoris M78 was evaluated in the absence (A: ST1+M78) or presence (B: ST1+M78+H25) of Lactiplantibacillus plantarum H25—another indigenous ripening strain—under real cheesemaking conditions. Three pilot-scale trials of fresh (6-day-old) Galotyri PDO cheese were made from boiled milk by an artisanal method using simple equipment, followed by cold ripening of the A1–A3 and B1–B3 cheeses at 4 °C for 30 days. All of the cheeses were analyzed microbiologically and for pH, gross composition, proteolysis, sugar and organic acid contents, and sensorial attributes before and after ripening. The artisanal (PDO) Galotyri manufacturing method did not ensure optimal growth of the ST1+M78 starter as regards the constant ability of the thermophilic strain ST1 to act as the primary milk acidifier under ambient (20–30 °C) fermentation conditions. Consequently, major trial-dependent microbial and biochemical differences between the Acheeses, and generally extended to the Bcheeses, were found. However, high-quality Galotyri was produced when either starter strain predominated in the fresh cheeses; only trial A1 had microbiological and sensory defects due to an outgrowth of post-thermal Gram-negative bacterial contaminants in the acidified curd. The H25 adjunct strain, which grew above 7 to 9 log CFU/g depending on the trial, had minor effects on the cheese’s pH, gross composition, and proteolysis, but it improved the texture, flavor, and the bacteriological quality of the Bcheeses during processing, and it exerted antifungal effects in the ripened cheeses.

The formation of biogenic amines (BAs) in artisan Galotyri PDO cheeses fermented with Sterptococcus thermophilus ST1 and the Greek indigenous nisin A-producing Lactococcus lactis spp. cremoris M78 (A1cheese), or with the A1 starter supplemented with either the enterocin A-B-P-producing Enterococcus faecium KE82 (A2cheese) or the multi-functional Lactiplantibacillus plantarum H25 (A4cheese) adjunct strains was evaluated. Three pilot-scale cheese trials, GL1, GL2, and GL3, made from boiled ewes’ milk, were analyzed for their BA contents before and after cold ripening at 4 °C for 30 days. Total BAs of the fresh GL1 and GL3 cheeses (pH 4.3–4.5) were below 50 mg/kg, except for the A1/GL1 and A1/GL3 cheeses, which contained ca. 300 mg/kg (81.2% histamine) and 1250 mg/kg (45.6% putrescine) BAs, respectively. Whereas due to an outgrowth (>7 log cfu/g) of post-thermal Gram-negative bacteria contaminants during fermentation, most fresh GL2 cheeses (pH 4.7–5.0) accumulated more than 1500 mg/kg of total BAs, which exceeded 3800 mg/kg in all GL2 cold-ripened cheeses due to major increases in cadaverine and putrescine. Tyramine and histamine exceeded 500 mg/kg in the fresh A1/GL2cheeses. Conversely, total BAs remained or declined below 50 mg/kg in all cold-ripened GL3 cheeses. None of the starter or adjunct cultures could be correlated with a specific BA increase, despite E. faecium KE82, which increased at 7.6–9.2 log cfu/g in the A2 cheeses is a strong tyramine producer in culture BA broth with 1% tyrosine in vitro. The adoption of strict hygienic measures during artisan Galotyri PDO cheese production (trial GL3) enabled the best performance of all starter LAB strain combinations and reduced BA formation, whereas the high presence of Gram-negative decarboxylating bacteria contaminants compromised cheese (trial GL2) safety.

Soft spread cheese is highly perishable, and conventional packaging offers limited protection against surface spoilage. Here, we present a sustainable, multifunctional solution: edible films made from whey protein concentrate (WPC), a valuable by-product of the cheese industry, incorporated with the probiotic Lactobacillus acidophilus LA5 (LA5). The objective of this study was to evaluate these films as active coatings for soft cheese, specifically assessing their physicochemical properties, probiotic viability during storage and simulated gastric transit, and their impact on cheese microbial stability and sensory quality over 60 days. Applied as active coatings on soft cheese stored at 4 °C for 60 days, these films were evaluated for their physicochemical properties, probiotic viability, microbial stability, and sensory acceptance. The incorporation of LA5 did not significantly alter film thickness (control: 0.20 ± 0.03 mm; test: 0.18 ± 0.02 mm), moisture content (control: 33.42 ± 0.54%; test: 32.34 ± 1.28%), or water solubility (control: 21.44 ± 1.14%; test: 22.89 ± 0.75%) (p > 0.05). However, mechanical properties were markedly modified: tensile strength decreased from 35.42 ± 5.38 MPa (control) to 6.04 ± 0.55 MPa (test), while elongation at break increased from 4.87 ± 0.93% to 68.23 ± 3.46% (p < 0.05), indicating a transition from rigidity to flexibility upon probiotic incorporation. The probiotic strain exhibited exceptional resilience, retaining 100% viability during simulated gastric exposure at both day 0 and day 30 of storage. During cheese storage, LA5 counts in test film-coated samples remained above the recommended therapeutic threshold (10⁶ cfu/g), starting at 7.44 ± 0.15 log(cfu/g) on day 0 and maintaining 6.56 ± 0.20 log(cfu/g) after 60 days. Critically, yeast and mold spoilage were delayed in probiotic-coated cheese, with detectable growth appearing only at day 60 (1.64 ± 1.34 log(cfu/g)), whereas uncoated cheese showed spoilage as early as day 28 (1.33 ± 1.62 log(cfu/g)). Sensory evaluation revealed no significant differences (p > 0.05) between the coated and uncoated samples for color, appearance, texture, flavor, or overall acceptability. By valorizing a dairy by-product into an active, probiotic-loaded edible film, this approach offers a sustainable, waste-reducing strategy that enhances cheese preservation while delivering added functional value—bridging the gap between food packaging and nutrition. Sensory evaluation (n = 8, preliminary) indicated no significant differences between coated and uncoated samples, but these results require confirmation with a larger, validated panel.

Sodium chloride (NaCl) is a multifunctional component of cheese manufacture that contributes to flavor, microbial control, moisture regulation, texture formation, product safety, and shelf stability. However, the association between excessive dietary sodium intake, elevated blood pressure, and cardiovascular disease has increased demand for reduced-sodium foods. Cheese reformulation is particularly challenging because reducing NaCl may simultaneously modify water activity, microbial ecology, acidification, proteolysis, lipolysis, texture, flavor development, and sensory acceptance. Accordingly, the purpose of this review is to critically evaluate the scientific evidence concerning direct NaCl reduction, partial replacement with mineral salts, flavor-enhancement approaches, modified salting and processing technologies, and complementary preservation strategies in cheese. Particular attention is given to the mechanisms through which these interventions affect microbial succession, ripening biochemistry, rheological properties, safety, shelf life, and consumer acceptance. The review also evaluates the limitations affecting industrial implementation, including process reproducibility, regulatory compliance, mineral accumulation in recirculated brines, ingredient costs, and environmental considerations. Current evidence indicates that no single strategy is universally applicable. Instead, safe and acceptable sodium reduction requires cheese-specific combinations of salt replacement, process control, microbial management, and sensory optimization.