Food Packaging and Shelf Life最新文献

Fresh-cut iceberg lettuce is appreciated by consumers for its nutritive properties, convenience, and ease of use. Producers are then pushed to preserve the quality of these products by using modified atmosphere packaging (MAP). In this study, the influence of passive MAP (air) or active MAP (1–5 % O₂), on several quality attributes of fresh-cut iceberg lettuce samples was evaluated during storage time (from 3 to 14 d) at 4 °C. The respiration rate and the electrolyte leakage values of samples packaged in active MAP were higher than those of fresh-cut iceberg lettuce stored in the air, indicating stressful storage conditions. Inverse trends were observed for O-quinones content and browning index until the end of the storage period. Sensory analysis highlighted that active MAP has preserved the visual quality, limiting the browning of the cut surfaces. On the other hand, active MAP modified the sensory profile after 3 d at 4 °C, and samples scored below the marketability limit for both odor and off-odor. Finally, a volatile organic compound characterization by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC–MS) allowed the identification of target molecules that could signal a decrease in food quality under different conditions. A total of 118 compounds were identified and, among them, ethyl alcohol and acetaldehyde were identified as the best quality markers for passive MAP and active MAP samples, respectively, while ethyl acetate could represent a good compromise to assess the quality of fresh-cut iceberg lettuce, regardless of MAP conditions.

The coatings on aluminum beverage can lid interiors can be prone to long-term degradation due to the high impact forces during fabrication and the corrosive nature of beverages. Multi-month tests are required to assess their resistance to this degradation. This study aims to present an innovative can lid coating testing method that incorporates in-situ Electrochemical Impedance Spectroscopy (EIS) monitoring under real-world conditions and with actual beverages. A robust testing chamber was meticulously engineered to house the 3D-shaped lid and maintain the conditions found in a beverage can. Experiments were conducted at stressed and non-stressed conditions, assessing different coatings and different beverages. The developed method has the potential to mimic the multi-month pack tests and offers a quicker, more insightful, and less laborious alternative for the lid coating degradation assessment. Ultimately, this method could help in improving the longevity and quality of aluminum beverage cans.

This study investigated the characteristics of biodegradable films prepared from gelatin derived from jellyfish Acromitus flagellatus using hot water extraction (F-JFG-HW) and microwave-assisted extraction (F-JFG-MW), in comparison to the cold-water fish skin gelatin (F-FG) and porcine skin gelatin (F-PG) based films. Both jellyfish gelatin films were darker compared to F-PG and F-FG. The tensile strength of jellyfish gelatin-based films was lower than that of F-PG but higher than that of F-FG. Both jellyfish-gelatin film types exhibited higher elongation at break, water vapour transmission rates, and antioxidant potential compared to F-FG and F-PG. The scanning electron microscopic analysis revealed that jellyfish gelatin films exhibited granular and porous surface structures and less compact internal structures compared to F-FG and F-PG. Both jellyfish gelatin-based films and F-FG films were 100 % water soluble and completely biodegradable after 24 h of incorporation in soil, while F-PG films biodegraded completely after 2 days.

Mechanically recycled plastics used in food packaging are consistent with the current circular economy concept. In this study, the effects of recycled polypropylene (rPP) content on film properties and the migration of processing aids in the film to food simulant and milk were studied by self-made rPP films. The results showed that the rPP and processing aids increased the transparency of the films. However, the presence of tiny particles in the rPP film reduced its elongation at break. Furthermore, rPP and processing aids decreased the thermal stability of the film. At 70 °C for 2 h, the total migration order of the processing aids to food simulant and milk was 50 % ethanol (55.78–64.17 mg/kg) > whole milk (10.32–10.66 mg/kg) > low-fat milk (6.39–7.04 mg/kg) > skim milk (4.88–5.47 mg/kg). The migration of processing aids into milk in films containing 50 % and 100 % rPP was similar to that of virgin polypropylene (vPP) films, which indicates that rPP does not promote processing aid migration. Moreover the overall migration order of processing aids to 2 % (w/v) food ingredient aqueous solution was lecithin (3.05 mg/kg) > glyceryl trilaurate (2.68 mg/kg) > cholesterol (1.33 mg/kg) > NaCl (0.33 mg/kg) > casein (0.32 mg/kg) > lactose (0.29 mg/kg) > water (0.16 mg/kg). This confirmed that milk fat was the primary cause of processing aids migration from the film, and the kind of milk fat also had an effect on processing aids migration. Therefore, as long as the basic performance and food safety of packaging are met, a certain proportion of rPP can be added to vPP to achieve sustainable development of packaging.

Starch-based materials are susceptible to moisture, leading to sticking and instability. Coating with hydrophobic biodegradable materials improves their stability. This research produced multilayer biodegradable packaging based on thermoplastic cassava starch (TPS) blended with poly(butylene adipate-co-terephthalate) (PBAT). TPS/PBAT mixtures were produced via blown film extrusion before coating with PBAT solution. Different TPS content (up to 80 %) and types of modified cassava starch namely native starch (NS), hydroxypropylated starch (HS), acetylated starch (AS), and octenyl-succinated starch (OS) were investigated for micro and chemical structure, delamination, and PBAT coating deposition on TPS/PBAT multilayer film. IR spectra of the peak at 3300 cm⁻¹ (O-H stretching of TPS) was absent after coating, suggesting reduced TPS content on the film surface, while 1717 cm⁻¹ (CO from carbonyl groups of PBAT), became sharper, indicating that PBAT deposition covered the film surface. The X-ray diffractogram showed a 2θ peak located at 24.4° (starch crystallinity) in the coated NS film; however, the peak was absent in coated HS, AS, and OS films because bulky chemical-grafted modified starch prevented molecular arrangement. Hydrophilic NS showed delamination and film substrate swelling after 60 s of direct contact with a sessile drop of water, indicating poor affinity. Hydrophobic-modified AS and OS significantly improved affinity with the PBAT coating layer giving a higher contact angle (105–112°), preventing delamination and substrate swelling and indicating increased water resistance. AS and OS (60 %) had higher shrinkage (23.78 % and 47.33 %) and a thicker coating layer (11.51 and 10.35 µm) due to greater polymer-solvent interaction. Hydrophobic-modified starch successfully improved the interaction between film layers and increased PBAT deposition.

A coupled experimental and modelling approach was used to develop an adapted PHBV active film with Lauroyl Arginate Ethyl (LAE®) as an antimicrobial compound incorporated in the bulk or as a coating to prolong the shelf life of cheese. The minimum inhibitory concentration (MIC) of LAE® was evaluated in the range of 25–100 ppm against spoilage and pathogenic microorganisms, such as Micrococcus luteus, Penicillium roqueforti, Salmonella enteritidis, and Pseudomonas putida. Film production induced a loss of 50 % of LAE® when introduced into the bulk, whereas only 4 % was lost in the case of incorporation by coating. When in contact with food simulant D1 (50 % ethanol), a release of 43 % and 34 % of LAE® was achieved in 10 days at 20 °C for LAE® incorporated as a coating and in the bulk, respectively, while a lower release level of 34 % and 14 % respectively was observed in food simulant C (20 % ethanol), confirming the interest to use active coating for fatty foods. The developed packaging was well adapted to reach the MIC while remaining below the admissible daily intake. The results also showed that the PHBV film activated with LAE® incorporated as a coating was as effective as modified atmosphere packaging (MAP) to preserve cheese against microorganism growth.

The preservation of fruits has always been a research hotspot. In this research, titanium dioxide(TiO₂) exhibiting diffraction peaks characteristic of both anatase and rutile phases was synthesized. Subsequently, photocatalytic films loaded with the TiO₂ were fabricated using a twin-screw extruder combined with an extrusion casting technique. The films demonstrated a highest ethylene photocatalytic degradation efficiency of 88.57 %. The addition of TiO₂ significantly enhanced the hydrophilicity of the films, with a maximum increase of 8.08 %. The tensile strength and elongation at break of the films were also improved. The optical properties, barrier properties and mechanical properties revealed that the film may make contributions to slowing down light aging, reducing weight loss of strawberries and increasing the load-bearing property. Furthermore, fresh-keeping experiment proved that the photocatalytic films could markedly slow down the appearance change, reduce weight loss and TBARS accumulation while decelerating the decline of TSS and antioxidant capacity in strawberries.

Minimally processed fruits and vegetables (F&V) are highly prone to oxidative deterioration and despite many efforts, no tangible solution has been found. Thus, this study was designed to evaluate the influence of antioxidant-releasing PLA (polylactic acid) and PP (polypropylene) films incorporated with orange peel extract (OPE) on the quality of cherry tomatoes during storage. Films were characterized based on color parameters, barrier properties and potential migration of volatile compounds from packaging into the food systems. The success of OPE encapsulation and molecular interactions between extract and polymeric chains was confirmed by FT-IR. The release analysis was performed in terms of DPPH radical scavenging activity and through GC-MS analysis (through liquid injection and SPME). Finally, the influence of the packaging material on the quality of cherry tomatoes was ascertained through oxidative enzyme activity and the production of volatile organic compounds. The effect of the extract on the oxygen permeability depends by the film. There was a significant difference (p < 0.05) in compounds that migrated from the control and active PLA films as observed through GC-MS. Finally, cherry tomatoes packed with active PLA films displayed more total polyphenolic content (TPC) retention and reduced volatile compounds (i.e., hexanal) at the end of storage as compared to PP films. Thus, active PLA films have the potential to be used as a replacement packaging material to PP for cherry tomatoes.

Biodegradable polyvinyl alcohol (PVA) and hydrophobically modified deacetyl konjac glucomannan (DK) films loaded with cinnamaldehyde (CA) emulsion were developed and characterized. The particle size of 957.4 nm and encapsulation rate of 91.23 % confirmed that CA had been embedded in the O/W emulsion system. SEM and AFM analysis showed that the PVA/DK film was more compatible, while the CA emulsion provoked bubbles and bumps on the surface, significantly gaining roughness (Ra). Besides, the water absorbency and water vapors permeability of DK after acetylation modification was lower. Meanwhile, PVA and DK had complementary roles, blending the two to enhance the water resistance of PVA and ameliorate the fragile defects of DK while accelerating the degradation of the film. Above all, the CA emulsion film possesses a vigorous antibacterial effect on Escherichia coli and Staphylococcus aureus, and the PVA/DK/CA film has a potential application in food packaging.

The safety assessment of food-contact plastic products is crucial for protecting consumers from potential harmful chemical contaminants. This study investigated novel contaminants and substances of concern in self-heating food containers, focusing on the release of microplastics (MPs) and the migration of volatile organic compounds (VOCs). Using micro-Raman spectroscopy, we simulated actual self-heating condition to determine the abundance, size, and size distribution of released MPs. Results showed MPs abundance ranging from 1.7 × 10⁶ to 3.4 × 10⁶ particles/L, with an average of 2.4 × 10⁶ particles/L, where over 98 % of particles were smaller than 20 µm. For VOCs migration, we employed direct immersion solid-phase micro-extraction coupled with comprehensive two-dimensional gas chromatograph-tandem quadrupole-time-of-flight mass spectrometry (DI-SPME-GC×GC-QTOF-MS) under three migration conditions. We identified 41 VOCs, including saturated hydrocarbons, fatty acyls, organoxygen compounds, unsaturated hydrocarbons, benzene derivatives, and phenol ethers. Risk substances such as Dibutyl phthalate, Benzophenone, and 4-Methylbenzophenone were detected in three samples. Semi-quantitative analysis and toxicity classification revealed that the maximum migration of all analytes remained below corresponding limit values, indicating a generally low risk to consumers.