Development of an active biogenic silver nanoparticles composite film based on berry wax and chitosan for rabbit meat preservation.

This study aimed to develop an eco-friendly active biogenic nanocomposite film through the complexation of silver nanoparticles (AgNPs), berry wax (BYW), and chitosan (CT) for maintiaing rabbit functional meat freshness. AgNPs were synthesized using Chinese medicinal paeoniaceae petal extract, and they were loaded at various concentrations (0.5 %, 0.75 %, 1.0 %, 1.25 %, and 1.5 % based on CT w/w) into the CT/BYW complex. The AgNPs exhibited an average size of 55 nm and a zeta potential of -26.3 mV with a spherical shape. The particle size and zeta potential of the film dispersions were 370.5-529.5 nm and 40.17-49.345 mV, respectively. FTIR, SEM, and XRD results showed compatibility among AgNPs and CT/BYW structure. The film water vapor permeability and light transparency decreased from 6.5 to 3.5 and 10 to 0.78 %, respectively, while opacity increased from 1.76 to 9.96 % with increasing concentrations of AgNPs. Among them, the film composite CT/BYW/AgNPs1.5% had better antioxidant and antibacterial properties, which was then applied for rabbit meat preservation at 4 °C for 16 days of storage. CT/BYW/AgNPs1.25%-packed sample had lower values of TVB-N, TBARS, TVC, and pH with greater retention of color properties compared to the control sample, which describes its ability to maintain meat freshness.

Fabrication of biopolymer stabilized microcapsules for enhancing physicochemical stability, antioxidant and antimicrobial properties of cinnamon essential oil.

The current study entails the encapsulation validity to enclose naturally occurring food preservatives, such as cinnamon essential oil (CM), within various wall materials. This approach has demonstrated enhanced encapsulated compounds' stability, efficiency, and bioactivity. The base carrier system consisted of a solid lipid (Berry wax, RW) individually blended with whey protein (WYN), maltodextrin (MDN), and gum Arabic (GMC) as wall materials. The resulting formulations were freeze-dried: WYN/RW/CM, MDN/RW/CM, and GMC/RW/CM. The study comprehensively analyzed encapsulation efficiency, morphology, crystallinity, thermal, and physiochemical properties. When RW was combined with WYN, MDN, and GMC, the microcapsule WYN/RW/CM showed the highest efficiency at 93.4 %, while the GMC/RW/CM exhibited the highest relative crystallinity at 46.54 %. Furthermore, the investigation assessed storage stability, release of bioactive compounds, and oxidative stability during storage at 4 °C/ 25 % RH ± 5 % and 25 °C/40 % RH ± 5 % for 55 days, revealing optimal stability in the WYN/RW/CM microcapsule. Additionally, the antimicrobial activity was assessed at various concentrations of microcapsules, revealing their inhibitory effect against Escherichia coli (gram-negative) and Staphylococcus aureus (gram-positive) bacteria. The WYN/RW/CM microcapsule exhibited the highest inhibition activity in both strains, reaching 40 mm. This study demonstrates that combining WYN with RW as a wall material has greater efficiency in encapsulation and potential uses in various industrial sectors.

Aerogel colorimetric label sensors based on carboxymethyl cellulose/sodium alginate with black goji anthocyanin for monitoring fish freshness.

A novel colorimetric aerogel was developed by the complexation of carboxymethyl cellulose (CMC), sodium alginate (SA), and black goji anthocyanin (BGA) followed by freeze-drying for monitoring fish (Coho salmon) freshness during storage at 4 °C and 25 °C. The various aerogels (C/S/B3:1, C/S/B2:1, C/S/B1:1, C/S/B1:2, and C/S/B1:3) externally and internally were characterized using SEM, FTIR, XRD, DSC, and TGA. Among them, the aerogel composite C/S/B1:2 exhibited the most uniform pore size, largest specific surface area, rapid color changes in various alkaline vapors (5 µM and 50 µM), and better mechanical strength. Furthermore, the colorimetric aerogel became dark blue from light purple during fish storage at temperatures of 4 °C and 25 °C when it reached pH 7.49 and 7.33, TVC 8.9 × 107 CFU/g and 8.5 × 107 CFU/g, and TVB-N 33.8 mg/100 g and 26.12 mg/100 g, respectively, indicating fish completely deteriorated. Taken together, the colorimetric aerogel composite C/S/B1:2 was promising for determining fish freshness, which could be utilized as a non-destructive and useful intelligent sensor in monitoring various fish and meat freshness and/or quality.

Berry wax improves the physico-mechanical, thermal, water barrier properties and biodegradable potential of chitosan food packaging film.

Chitosan (CT) is extensively applied in developing food packaging films due to its non-toxic, biodegradable, and good film-forming properties. But CT-based single polymer film has issues with poor physico-mechanical, thermal, and light barrier properties. Therefore, this study aimed to incorporate natural berry wax (BYW) at various concentrations (5 %, 10 %, 15 %, 20 %, and 25 %, wt%) into CT to improve the quality characteristics of CT film. The microstructure of the film matrix was effectively proven to be compatible with BYW through the utilization of SEM, XRD, and FTIR spectroscopy. The results demonstrated that the quality parameters of CT/BYW composite film were significantly affected by the increasing concentration of BYW. The integration of BYW with a concentration of 5 % to 20 % to CT substantially improved the film characteristics by reducing moisture content, swelling power, solubility, and water vapor permeability, increasing the film's opacity, thermal stability, and tensile strength as well as enhancing the biodegradable potential. Furthermore, CT/BYW films showed higher thermal stability and UV and visible light resistance compared to pure CT film. Taken together, the CT film with 20 % berry wax showed the best film characteristics and biodegradable potential, which could be promising for enhancing the shelf-life of various food products.

Replacement of polyethylene oxide by peach gum to produce an active film using Litsea cubeba essential oil and its application in beef.

This study evaluated the effects of adding various concentrations (0 %, 1 %, 2 %, and 3 %) of peach gum (PG) to films made from polyethylene oxide (PEO) combined with Litsea cubeba essential oil (LCEO) to be utilized as active packaging for food in the future. The findings showed that the film containing PG 2 % concentration had the best physic-mechanical properties. In films made with PG, the glass transition temperature was significantly improved. Combining PG and PEO resulted in films that were brighter in color, had lower WVP values, and had the lowest water activity. Furthermore, XRD demonstrated that PG additions were compatible with the film of PEO blended with LCEO. The PG films formulated with PG presented high antioxidant and antibacterial activity against Staphylococcus aureus and E. coli. Wrapping beef with P2G2 film led to maintaining its quality with suitable levels of pH, TBARS, and TVB-N. This also decreased the number of E. coli and S. aureus in beef throughout the storage period. The results indicate that adding PG to PEO films enhances their suitability for food preservation.

A visual bi-layer sensor based on Agar/TiO2/butterfly bean flower anthocyanin/κ-carrageenan with photostability for monitoring Penaeus chinensis freshness.

Visual indicator bi-layer films were manufactured incorporating κ-carrageenan, butterfly pea flower anthocyanin, varying Nano­titanium dioxide (TiO2) content and agar for Penaeus chinensis (Chinese white shrimp) freshness detection. The κ-carrageenan-anthocyanin (CA) layer served as indicator, while the TiO2-agar (TA) layer functioned as the protective layer to improve the photostability of film. The bi-layer structure was characterized by scanning electron microscopy (SEM). The TA2-CA film had the best tensile strength with a value of 17.8 MPa and the lowest water vapor permeability (WVP) value of bi-layer films was 2.98 × 10-7 g.m-1.h-1.pa-1. The bi-layer film protected anthocyanin against exudation when immersed in aqueous solution of varying pH. The TiO2 particles filled the pores of the protective layer, increasing the opacity from 1.61 up to 4.49 significantly improving the photostability with a consequent slight color change under illumination of UV/visible light. Under UV irradiation, the TA2-CA film had no significant color change with a ΔE value of 4.23. Finally, the TA2-CA films showed an obvious color change from blue to yellow green in the early stages of Penaeus chinensis putrefaction (≤48 h) then the color change and Penaeus chinensis freshness were well correlated (R2 = 0.8739).

Classification of Black Mahlab seeds (Monechma ciliatum) using GC-MS and FT-NIR and simultaneous prediction of their major volatile compounds using chemometrics.

The identification of geographical origin is an important factor in assessing the quality of aromatic and medicinal seeds such as Black Mahlab (Monechma ciliatum). However, at present, there are no studies concerning Black Mahlab Seeds (BMSs). To identify the geographical origin of BMSs, we have used gas chromatography-mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FT-NIR) combined with chemometrics. Chemometrics analysis showed that FT-NIR and GC-MS can be used to discriminate the geographical origin of BMSs. FT-NIR coupled with the partial least squares regression (PLSR) was applied to develop the calibration models. The calibration models had a coefficient of determination (Rc2) of 0.82 for coumarin and 0.81 for methyl salicylate. The prediction model (Rp2) values ranged from 0.83 for coumarin to 0.77 for methyl salicylate. Overall, the chemometrics presented correct classification, and PLSR accurately predicted the volatiles, with an RMSEP range of 0.9 to 0.16 for the two volatiles targeted.

Smart films of carbohydrate-based/sunflower wax/purple Chinese cabbage anthocyanins: A biomarker of chicken freshness.

Innovative pH-colorimetric sensor film was fabricated from agar and methylcellulose matrix (AM) with various concentrations of sunflower wax (SFW) (6%, 9%, 12%, and 15% w/w) combined with purple Chinese cabbage (CPC) anthocyanins for tracking chicken breast freshness. A bio-composition film AM/CPC with (hydrophobic) SFW exhibited significant color variations in acidic pH level of (2-6) and a slight shift in alkaline pH levels ranging from (7-12), as well as marked color change due to ammonia vapor. Microstructure analyses revealed that SFW was fixed effectively into the AM-CPC matrices. The incorporation of varying SFW concentrations enhanced the mechanical, thermal, antioxidant activity, reduced anthocyanin release and physical properties (mainly water vapor permeability), with the best performance at AM/CPC/9% SFW. Interestingly, SFW films demonstrated perfect defense opposing UV-vis and visible light. Finally, it was proved that the efficiency of the pH-colorimetric film as an indicator for evaluating the freshness of chicken breast.

Smart films fabricated from natural pigments for measurement of total volatile basic nitrogen (TVB-N) content of meat for freshness evaluation: A systematic review.

Major databases were searched from January 2012 to August 2021 and 54 eligible studies were included in the meta-analysis to estimate the overall mean of total volatile basic nitrogen (TVB-N) in meat. The mean of TVB-N was 24.96 mg/100 g (95 % CI:23.10-26.82). The pooled estimate of naphthoquinone, curcumin, anthocyanins, alizarin and betalains were 25.98 mg/100 g (95 %CI:19.63-32.33), 30.03 mg/100 g (95 %CI: 24.15-35.91), 24.92 mg/100 g (95 %CI: 22.55-27.30), 23.37 mg/100 g (95 %CI:19.42-27.33) and 19.50 mg/100 g (95 %CI:17.87-21.12), respectively. Meanwhile, subgroups based on meat types showed that smart film was most used in aquatic products at 27.19 mg/100 g (95 %CI:24.97-29.42), followed by red meat at 19.69 mg/100 g (95 %CI:17.44-21.94). Furthermore, 4 °C was the most storage temperature used for testing the performance of smart films at 25.48 mg/100 g (95 %CI:23.05-27.90), followed by storage at 25 °C of 25.65 mg/100 g (95 %CI:22.17-29.13). Substantial heterogeneity was found across the eligible studies (I2 = 99 %, p = 0.00). The results of the trim-and-fill method demonstrated publication bias was well controlled.

Intelligent colorimetric pH sensoring packaging films based on sugarcane wax/agar integrated with butterfly pea flower extract for optical tracking of shrimp freshness.

A novel pH colorimetric film was prepared from various sugarcane wax (SW) concentrations (1, 1.5 and 2% w/v) on agar matrix (Agr) combined with butterfly pea flower (BF) extract for monitoring the shrimp freshness. A combination of BF anthocyanins with SW as lipid (hydrophobic) showed different changes in color under acidic conditions (pH 2-6) with slight changes under alkalinity (pH 7-12), which matched the visual color changes of two different ammonia vapors (50 and 100 mmol/l). FTIR, XRD spectra, and SEM micrographs revealed that SW was effectively fixed into the Agr-BF network during the film-forming process. The different homogenized SW films enhanced the physical and mechanical properties without significant differences in elongation and water vapor permeability. Remarkably, SW films displayed complete protection against UV-vis light (0%) and valuable reduction in visible light. This study presents SW colorimetric films as promising natural derivatives for smart packaging in tracking food freshness.