Effect of Morus alba leaf extract dose on lipid oxidation, microbiological stability, and sensory evaluation of functional liver pâtés during refrigerated storage.

Mulberry (Morus alba L.), and above all the extract from the leaves of this plant, is a natural medicine that has been used in traditional medicine for hundreds of years. Mulberry leaves contains polyphenol compounds: flavonoids, coumarins, numerous phenolic acids, as well as terpenes and steroids. The antioxidant effect of these compounds may be beneficial to the fat fraction of meat products, thereby increasing their functional qualities. The aim of the study was to evaluate the effectiveness of the use of mulberry water leaf extract, as an additive limiting adverse fat changes and affecting the functionality in model liver pâtés. Pork pâtés were prepared by replacing 20% of animal fat with rapeseed oil (RO), and water extract of mulberry leaves was added in the proportion of 0.2%, 0.6% and 1.0%. It has been shown that the addition of mulberry leaf extract delayed the appearance of primary and secondary fat oxidation products. The most effective antioxidant effect during 15-day storage was observed in the sample with the addition of 0.6% and 1.0% water mulberry leaf extract. These samples also showed inhibiting activity against angiotensin-converting enzymes and cholinesterase's. During storage, the tested pâtés had a high sensory quality with unchanged microbiological quality. Mulberry leaf extract can be an interesting addition to the production of fat meat products, delaying adverse changes in the lipid fraction and increasing the functionality of products.

Evaluation of antimicrobial activities of plant aqueous extracts against Salmonella Typhimurium and their application to improve safety of pork meat.

Nine odorless laboratory-collected hydro-distilled aqueous extracts (basil, calendula, centrifuged oregano, corn silk, laurel, oregano, rosemary, spearmint, thyme) and one industrial steam-distilled oregano hydrolate acquired as by-products of essential oils purification were screened for their in vitro antimicrobial activity against three Salmonella Typhimurium strains (4/74, FS8, FS115) at 4 and 37 °C. Susceptibility to the extracts was mainly plant- and temperature-dependent, though strain dependent effects were also observed. Industrial oregano hydrolate eliminated strains immediately after inoculation, exhibiting the highest antimicrobial potential. Hydro-distilled extracts eliminated/reduced Salmonella levels during incubation at 4 °C. At 37 °C, oregano, centrifuged oregano, thyme, calendula and basil were bactericidal while spearmint, rosemary and corn silk bacteriostatic. A strain-dependent effect was observed for laurel. The individual or combined effect of marinades and edible coatings prepared of industrial hydrolate and hydro-distilled oregano extracts with or without oregano essential oil (OEO) was tested in pork meat at 4 °C inoculated with FS8 strain. Lower in situ activity was observed compared to in vitro assays. Marinades and edible coatings prepared of industrial oregano hydrolate + OEO were the most efficient in inhibiting pathogen. Marination in oregano extract and subsequent coating with either 50% oregano extract + OEO or water + OEO enhanced the performance of oregano extract. In conclusion, by-products of oregano essential oil purification may be promising alternative antimicrobials to pork meat stored under refrigeration when applied in the context of multiple hurdle approach.

Properties of Banana (Cavendish spp.) Starch Film Incorporated with Banana Peel Extract and Its Application.

The objective of this study was to develop an active banana starch film (BSF) incorporated with banana peel extract. We compared the film's properties with commercial wrap film (polyvinyl chloride; PVC). Moreover, a comparison of the quality of minced pork wrapped during refrigerated storage (7 days at ±4 °C) was also performed. The BSF with different concentrations of banana peel extract (0, 1, 3, and 5 (%, w/v)) showed low mechanical properties (tensile strength (TS): 4.43-31.20 MPa and elongation at break (EAB): 9.66-15.63%) and water vapor permeability (3.74-11.0 × 10-10 g mm/sm2 Pa). The BSF showed low film solubility (26-41%), but excellent barrier properties to UV light. The BSF had a thickness range of 0.030-0.047 mm, and color attributes were: L* = 49.6-51.1, a* = 0.21-0.43, b* = 1.26-1.49. The BSF incorporated with banana peel extracts 5 (%, w/v) showed the highest radical scavenging activity (97.9%) and inhibitory activity of E. coli O157: H7. The BSF showed some properties comparable to the commercial PVC wrap film. Changes in qualities of minced pork were determined for 7 days during storage at ±4 °C. It was found that thiobarbituric acid reactive substances (TBARS) of the sample wrapped with the BSF decreased compared to that wrapped with the PVC. The successful inhibition of lipid oxidation in the minced pork was possible with the BSF. The BSF incorporated with banana peel extract could maintain the quality of minced pork in terms of oxidation retardation.

Effect of ethanolic extract from Morus alba L. leaves on the quality and sensory aspects of chilled pork under retail conditions.

The aim of this study was to investigate the performance of ethanolic extract from Morus alba L. leaves (MLEE) in preserving chilled pork under retail conditions. The four treatments were 5 mg/mL sodium benzoate solution (SB), 1 mg/mL MLEE solution (high-concentration MLEE; HM), 0.5 mg/mL MLEE solution (low-concentration MLEE; LM), and 0 mg/mL MLEE solution (C). The quality characteristics, pH, thiobarbituric acid reactive substances values, metmyoglobin, total volatile basic nitrogen, and number of microbes of MLEE-treated chilled pork stored at 4 °C for 9 days were consistent with those obtained by the SB treatment and lower than those obtained by the C treatment. Sensory analyses showed that treatment of pork with MLEE did not have a negative impact on its sensory characteristics. MLEE can extend the shelf life of chilled pork from 3 days to 6 days (9 days) in first-class (second-class) fresh meat. Results suggest that MLEE could be a candidate resource in the preservation of chilled pork.

Effect of chitosan-gelatin coating containing nano-encapsulated tarragon essential oil on the preservation of pork slices.

There is an increasing demand for bio-based packaging materials incorporated with active nanoparticles as one of the new technologies to obtain food products with improved quality and extended shelf-life. The objectives of this study were to develop a chitosan-gelatin based edible coating incorporated with nano-encapsulated tarragon essential oils (TEO) and to investigate the effects of chitosan-gelatin coatings containing TEO or TEO-loaded nanoparticles (TEO-NPs) on the preservation of pork slices during refrigerated storage for 16 days. Nanoparticles with the average diameters of 246.27-504.60 nm were produced using different mass ratios of chitosan to TEO (1:0, 1:0.2, 1:0.4, 1:0.6, 1:0.8 and 1:1) by ionic gelation method. Zeta potential and encapsulation efficiency (EE) of the prepared TEO-NPs were 27.07-37.12 mV and 9.83-35.57%, respectively. TEO-NPs with the maximum EE were applied for preparing the edible coatings. The results suggested that the coating treatments could significantly inhibit quality deterioration of pork slices. Nano-encapsulation contributed to the sustained release of TEO and caused an improved antioxidant, antibacterial and sensory properties. The study suggests that chitosan-gelatin coating incorporated with TEO-NPs could be developed as a prospective active packaging to preserve pork slices.