Antibacterial and Antibiofilm Effects of Photodynamic Treatment with Curcuma L. and Trans-Cinnamaldehyde against Listeria monocytogenes.

Photodynamic inactivation (PDI) is a highly effective treatment that can eliminate harmful microorganisms in a variety of settings. This study explored the efficacy of a curcumin-rich extract, Curcuma L., (Cur)- and essential oil component, trans-cinnamaldehyde, (Ca)-mediated PDI against Listeria monocytogenes ATCC 15313 (Lm) including planktonic cells and established biofilms on silicone rubber (Si), polytetrafluoroethylene (PTFE), stainless steel 316 (SS), and polyethylene terephthalate (PET). Applying Ca- and Cur-mediated PDI resulted in planktonic cell reductions of 2.7 and 6.4 log CFU/cm2, respectively. Flow cytometric measurements (FCMs) coupled with CFDA/PI and TOTO®-1 staining evidenced that Ca- doubled and Cur-mediated PDI quadrupled the cell damage. Moreover, the enzymatic activity of Lm cells was considerably reduced by Cur-mediated PDI, indicating its superior efficacy. Photosensitization also affected Lm biofilms, but their reduction did not exceed 3.7 log CFU/cm2. Cur-mediated PDI effectively impaired cells on PET and PTFE, while Ca-mediated PDI caused no (TOTO®-1) or only slight (PI) cell damage, sparing the activity of cells. In turn, applying Ca-mediate PDI to Si largely diminished the enzymatic activity in Lm. SS contained 20% dead cells, suggesting that SS itself impacts Lm viability. In addition, the efficacy of Ca-mediated PDI was enhanced on the SS, leading to increased damage to the cells. The weakened viability of Lm on Si and SS could be linked to unfavorable interactions with the surfaces, resulting in a better effect of Ca against Lm. In conclusion, Cur demonstrated excellent photosensitizing properties against Lm in both planktonic and biofilm states. The efficacy of Ca was lower than that of Cur. However, Ca bears potent antibiofilm effects, which vary depending on the surface on which Lm resides. Therefore, this study may help identify more effective plant-based compounds to combat L. monocytogenes in an environmentally sustainable manner.

Levels of Contamination by Pesticide Residues, Polycyclic Aromatic Hydrocarbons (PAHs), and 5-Hydroxymethylfurfural (HMF) in Honeys Retailed in Europe.

Honey is consumed worldwide because of its nutritional, therapeutic and medicinal properties. Generally, honey should reach the consumer in a pure form, but it is often contaminated in various ways. Thus, this study was designed to check for the presence of pesticide residues, polycyclic aromatic hydrocarbon (PAH) levels, and the content of 5-hydroxymethylfurfural (HMF) in selected European honeys (26 samples) obtained from shops. The most frequently detected organochlorine pesticide (OCPs) was 4,4'-DDD, which was found in fourteen honey samples. Slovakian rapeseed honey was most polluted due to the presence of eight OCPs. The presence of organophosphorus pesticides (OPs) was detected in all the analysed samples, and at least one OP in each tested sample exceeded the acceptable limit. PAHs were detected in most of the analysed samples. As for PAH4s, benzo[a]pyrene was found in forest honey from Slovakia and in Polish lime tree honey, whereas wild flower honey from the UK contained the highest level of PAH4. The investigated honeys from Spain and France met the requirements for HMF content, while honeys of Slovak, Italian and Polish origin in most cases exceeded the established levels (40 mg/kg).

Folate Content and Yolk Color of Hen Eggs from Different Farming Systems.

This study aimed to compare folate contents in hen eggs from four different farming systems, namely organic, free range, barn, and cage one. Folate retention during egg boiling was studied as well. The contents of individual folate vitamers were determined using the high-performance liquid chromatography method (HPLC), following trienzyme treatment. Folate content in eggs differed significantly (p < 0.05) due to the rearing system, with the highest mean content determined in the eggs from organic farming (113.8 µg/100 g). According to this study, one egg (60 g) may provide 40-86 µg of folates, which corresponds to 10-22% of the recommended daily intake for adults, 400 µg according to the Nutrition Standards for the Polish Population. The predominant folate form found in egg was 5-methyltetrahydrofolate, which showed considerably greater stability under boiling compared to 10-formylfolic acid present in a lower amount. In most eggs tested, the losses in total folate content did not exceed 15%. The color of yolk of the most folate-abundant organic eggs, had the highest value of lightness (L*) and the lowest value of redness (a*). This, however, does not correspond to consumer preferences of intense golden yolk color.

Prevention of surface colonization and anti-biofilm effect of selected phytochemicals against Listeria innocua strain.

This work aimed to determine the ability of Listeria innocua (L.i.) to colonize eight materials found in food-processing and packaging settings and to evaluate the viability of the sessile cells. We also selected four commonly used phytochemicals (trans-cinnamaldehyde, eugenol, citronellol, and terpineol) to examine and compare their efficacies against L.i. on each surface. Biofilms were also deciphered in chamber slides using confocal laser scanning microscopy to learn more about how phytochemicals affect L.i. The materials tested were silicone rubber (Si), polyurethane (PU), polypropylene (PP), polytetrafluoroethylene (PTFE), stainless steel 316 L (SS), copper (Cu), polyethylene terephthalate (PET), and borosilicate glass (GL). L.i. colonized Si and SS abundantly, followed by PU, PP, Cu, PET, GL, and PTFE surfaces. The live/dead status ranged from 65/35% for Si to 20/80% for Cu, and the estimates of cells unable to grow on Cu were the highest, reaching even 43%. Cu was also characterized by the highest degree of hydrophobicity (ΔGTOT = -81.5 mJ/m2). Eventually, it was less prone to attachment, as we could not recover L.i. after treatments with control or phytochemical solutions. The PTFE surface demonstrated the least total cell densities and fewer live cells (31%) as compared to Si (65%) or SS (nearly 60%). It also scored high in hydrophobicity degree (ΔGTOT = -68.9 mJ/m2) and efficacy of phytochemical treatments (on average, biofilms were reduced by 2.1 log10 CFU/cm2). Thus, the hydrophobicity of surface materials plays a role in cell viability, biofilm formation, and then biofilm control and could be the prevailing parameter when designing preventive measures and interventions. As for phytochemical comparison, trans-cinnamaldehyde displayed greater efficacies, with the highest reductions seen on PET and Si (4.6 and 4.0 log10 CFU/cm2). The biofilms in chamber slides exposed to trans-cinnamaldehyde revealed the disrupted organization to a greater extent than other molecules. This may help establish better interventions via proper phytochemical selection for incorporation in environment-friendly disinfection approaches.

The Effect of Ginger Rhizome Addition and Storage Time on the Quality of Pork Meatloaf.

This study investigated the effect of ginger-rhizome addition and storage time on the physicochemical and sensory quality of pork meatloaf. Three types of pork meatloaf were evaluated: control and with 1% and 2% addition of ginger. All meatloaves were vacuum packaged and stored for 0, 7, 14, and 21 days at 4 °C. The addition of ginger rhizome significantly reduced lipid oxidation, and the higher inclusion rate was more effective in this regard. Ginger decreased red-colour saturation (a*) and increased colour brightness. The addition of ginger rhizome at 2% induced a greater decrease in meat hardness and improved chewiness in comparison with 1% addition. Products containing ginger differed from the control sample in aroma, texture, and taste, but no significant differences were found in the overall quality of the compared samples.

Effect of the Addition of Chia Seed Gel as Egg Replacer and Storage Time on the Quality of Pork Patties.

Two types of patties were prepared: control and with chia seeds gel instead of beaten egg. The patties were cooked in the steam-convection oven, vacuum packed and stored at 4 °C. The pork patties with chia addition were characterized by similar water activity and pH values to the control samples. They showed lower values of the b* colour parameter as well as colour saturation (C*) and hue angle values (h°) on the cross-section and lower values of colour parameters L*, a* and b* and C* on the surface than the controls. The addition of chia seeds improved the texture parameters of the tested products. Pork patties with chia seeds were softer and showed better chewiness than the control samples. Chia slowed down oxidative changes in pork patties during storage. The use of 8.0% addition of chia seeds was only slightly noticeable in taste of the pork patties and these samples received similar overall quality scores as control samples.

Effect of Different Cooking Methods on Folate Content in Chicken Liver.

Common liver sources in European countries include cow, chicken, duck, lamb and pig. Despite its decreasing popularity, liver is possibly one of the most nutrient-dense foods, being rich in high-quality protein and low in calories. In animals, the liver is the storage organ for folate. In this study, the effect of different cooking methods on folate vitamers content in chicken liver was investigated. Three folate derivatives, 5-CH3-H4PteGlu, H4PteGlu and 5-HCO-H4PteGlu, were identified in the analyzed samples using high performance liquid chromatography (HPLC). The folate content in liver after sous-vide (60 °C/75 min) and steaming (100 °C/30 min) did not differ significantly (p ≤ 0.05) from raw liver folate content (781 µg/100 g). Even liver cooked in a combi oven or grilled (which resulted in significant folate losses) showed much higher folate content, 455-631 µg/100 g and 612-715 µg/100 g, respectively, than the most folate-abundant plant foods. These findings are important as they demonstrate that processed liver has the potential to improve the supply of folate and meet the recommended daily requirements, particularly when folate deficiency is common worldwide.

The effect of ginger rhizome and refrigerated storage time on the quality of pasteurized canned meat.

The effect of ginger rhizome, in comparison with sodium ascorbate and butylated hydroxytoluene, and storage time at 5℃ on the quality of pasteurized canned meat was studied. Ginger rhizome was as effective as sodium ascorbate in inhibiting lipid oxidation. The canned meat with ginger rhizome was characterized by a lighter color and a lower contribution of redness than the remaining products. It was also characterized by the lowest hardness, springiness, and chewiness. In a sensory evaluation, meat with ginger rhizome was evaluated as juicier and softer than the remaining meat products. The results of this study indicate that ginger rhizome could be used in the place of synthetic antioxidants in pasteurized canned meat.

The effect of low-temperature thermal processing on the quality of chicken breast fillets.

The aim of this study was to evaluate the effect of the temperature and time of sous vide cooking on the quality of chicken breast fillets. Meat was thermally processed at six different combinations of temperature and time: 55℃ (260 min and 320 min), 58℃ (140 and 200 min) and 61℃ (90 and 150 min). Thermally processed chicken breasts were analysed for cooking loss, proximate composition, colour parameters, pH, texture parameters and sensory quality. Heat processing at a temperature of 58℃/200 min produced meat with the most desirable sensory quality. These fillets were characterized by the lowest moisture content, high protein content, lowest concentration of malondialdehyde, low shear force value, lowest hardness and chewiness, and the highest scores for tenderness and overall acceptance in sensory evaluation.

The effect of natural and synthetic antioxidants and packaging type on the quality of cooked poultry products during frozen storage.

The effect of oil-soluble rosemary extract, sodium erythorbate and their mixture, and the influence of packaging method (air and vacuum packaging) on the quality of cooked turkey meatballs stored at -20 ℃ was determined. The smallest changes in malondialdehyde content were observed in samples with the addition of the natural antioxidant regardless of the packaging method. The mixture of synthetic and natural antioxidants was more effective in retarding lipid oxidation than the synthetic antioxidant, and more desirable results were observed in vacuum-packaged samples than in air-packaged samples. The samples with the addition of oil-soluble rosemary extract were characterised by lower intensity of red colour, but this parameter was more stable during frozen storage. The results of a sensory analysis revealed that the application of oil-soluble rosemary extract with or without sodium erythorbate significantly inhibited the development of warmed-over flavour in cooked poultry products.

Influence of sous vide and steam cooking on mineral contents, fatty acid composition and tenderness of semimembranosus muscle from Holstein-Friesian bulls.

The effects of thermal processing method (sous vide and steam cooking) on Ca, Cu, Fe, Zn, Mg, Mn, K, Na contents, fatty acid composition, Warner-Bratzler shear force (WBSF) and eating quality in beef semimembranosus muscle from Holstein-Friesian bulls were evaluated in the study. Thermal processed meat was characterized by a higher content of Ca, Cu, and Zn and lower content of Na and K than raw meat. Steam-cooked beef showed higher retention values of Cu, Fe and Zn and lower for K and Na compared with sous vide samples. Steam-cooked beef was a good source of Fe and Zn and 100 g of the meat satisfied 118% for Zn recommendations for children. Steam cooking increased the proportion of C18:2, C18:3, C20:1, C20:4 and decreased the proportion of the sum of saturated fatty acids. Sous vide beef had a lower proportion of polyunsaturated fatty acids, including n-3, than steam-cooked beef, but a similar n-6/n-3 ratio. However, sous vide treatment caused lower cooking losses and produced meat products with lower WBSF values and better eating quality than steam cooking.

Addition of herbal extracts to the Holstein-Friesian bulls' diet changes the quality of beef.

Twenty four Holstein-Friesian bulls were randomly assigned to one of three dietary treatments: a control diet, diet O (supplemented with Optirum herbal extracts improving the functioning of the gastrointestinal tract of cattle), and diet OS (containing two herbal preparation: Optirum and Stresomix, used to reduce stress). The quality of longissimus lumborum (LL) and semimembranosus (SM) muscles were determined after 14 days of wet ageing. The diet influenced proximate composition, pH, water holding capacity, colour, shear force and some sensory quality attributes of beef, although the influence depended on the muscle type. The supplementation of the bulls' diet with two herbal preparations (OS diet) had a beneficial impact on technological properties and sensory tenderness of LL muscles. The herbal extracts O and OS had no negative effect on lipid oxidation or the sensory attributes of beef. Thus, it is recommended to use a combination of these two products in cattle feeding.