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In this study, nanoemulsion coatings of Froriepia subpinnataessential oil (FEO) in konjac gum (KG) are used to moderate the spoilage of quail meat in refrigerated conditions. For this purpose, first FEO was extracted by water distillation method and nanoemulsion of FEO (NFEO) was produced in konjac gum by ultrasonic waves. Then six quail treatments (T) including: T1: control, T2: KG coating, T3: KG + FEO at 500 ppm, T4: KG + FEO at 1000 ppm, T5: KG + NFEO at 500 ppm, T6: KG + NFEO at 1000 ppm) were produced during days 0, 4, 8, 12 and 16. After that, they were subjected to chemical (PV, TBA, FFA, TVB-N, pH and tissue), microbial (TVC, PTC), and organoleptic evaluation. Based on the results, FEO has highly antimicrobial and antioxidant properties due to its bioactive compounds such as p-cymen-8-ol (46.49%), α-Terpinolene (11.58%), and limonene (8.95%). The particle size, microencapsulation efficiency, and zeta potential of NFEO were 119.25 ± 2.97 nm, 82.45 ± 2.15%, and − 15.35 ± 1.24%, respectively. The results related to the quality of quail meat showed that the edible coating of KG + NFEO effectively prevented the reduction of hardness and the increase of oxidation and microbial spoilage of quail (P < 0.05). In addition, during the storage period, KG + NFEO more effectively prevented microbial growth, oxidative spoilage, and organoleptic changes compared to other treatments (P < 0.05). The use of T6 increased the shelf life of the quail from 8 days (T1) to 16 days. Therefore, it is possible to use the NFEO in KG to maintain and improve the physicochemical, microbial, and sensory characteristics of quail meat during the storage period in the refrigerator.

The present study has investigated the effect of nano chitosan (NC)-Iranian tragacanth gum (ITG) composite film along with Eryngium campestreessential oil (ECE) on the shelf life of goat meat at refrigerator temperature (4 °C) during the storage period. For this purpose, the first 5 film treatments including NC, NC−ITG, and NC−ITG+ECE at 0.5%, 1%, and 1.5% of were produced and then the physical, mechanical, antioxidant, and antimicrobial characteristics of the films were determined. Next, six different treated groups (mentioned treatments and control (without film)) were examined for chemical (PV, TBA, TVB-N, pH, and color index), and microbial (TVC, PTC, Enterobacteriaceae, and lactic acid bacteria) and sensory evaluations for 16 days at 4 °C. The composite films containing ECE had better physical and mechanical properties compared to other films (P < 0.05) and these films had antioxidant properties (inhibition of DPPH free radicals) and high antimicrobial properties against the tested pathogenic bacteria (Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Bacillus cereus). The results showed that the NC−ITG+ECE significantly delayed the oxidation of fats in meat and was significantly effective in reducing pH and TVB-N compared to the control during the storage period (P < 0.05). The amount of TVC and PTC during the storage period in the meat treated with ECE at 1 and 1.5% remained below the suggested acceptable limit and the microbial spoilage significantly reduced in these samples compared to other samples. Also, the sensory evaluation results of meat packed with 1% and 1.5% ECE had a high overall acceptance during storage. The results showed that packing meat with NC−ITG+ECE has an inhibitory effect on increasing chemical and microbial spoilage. Considering the relatively similar inhibitory effect of 1% and 1.5% as well as economic efficiency, 1% of essential oil can be an optimal dose.

Edible films along with herbal essential oils can be a safe and suitable way to package food including ostrich meat. The present research was conducted to investigate the effects of the polylactic acid–Iranian tragacanth gum (PLA–ITG) composite film along with zygophyllum eichwaldiiessential oil (ZEO) on the shelf life of ostrich thigh meat stored at 4 °C. For this purpose, the first 5 film treatments were produced including PLA, PLA–ITG, and PLA–ITG with concentrations of 0.5%, 1%, and 1.5% ZEO, and the properties of the film were determined. The effect of the mentioned films along with the control treatment (without film) on the chemical (PV, TBA, TVB-N, pH, and color index) and microbial (TVC, PTC, Enterobacteriaceae, and lactic acid bacteria) and sensory properties of ostrich samples were evaluated. According to the results, adding ZEO improved the mechanical and physical characteristics of the composite film. PLA–ITG + 1.5% ZEO has the highest antioxidant (DPPH free radical inhibition) and antimicrobial properties (against the tested pathogenic bacteria) compared to others. The results of the second part showed that the samples packed with composite films containing ZEO showed lower (P < 0.05) chemical and microbial changes than the control. The film containing 1.5% ZEO had the best effects compared to other groups (P < 0.05). This treatment had chemical, microbial, and sensory limits until the end of the storage period, while the control sample could only be stored for 6 days. Therefore, from an environmental and economic point of view, it is recommended to use the (PLA- ITG) composite film with ZEO as biodegradable packaging to increase the shelf life of ostrich meat at 4 °C.

Polylactic acid (PLA) nanocellulose (NC) composite film and probiotic bacteria Lactobacillus caseiwere used to increase the shelf life of beluga fillet at refrigerator temperature (4 ± 1 °C). First, the physical and mechanical properties of the films (1: PLA, 2: PLA-NC, 3: PLA-NC + L. casei) were investigated. Then the packed fillets (with the mentioned films) and control (without film) were evaluated in terms of chemical (PV, TBA, TVB-N, and pH), microbial (TVC, lactic acid bacteria, and Enterobacteriaceae) and sensory properties on days 0, 4, 8, 12 and 16. According to the results, the addition of L.casei improved the physical properties of the film, but it harmed the opacity and mechanical properties. With the increase of storage time in the refrigerator, the viability of L. caseiin the film decreased and its values were equal to 6.12 log CFU/g (at the end of storage time), however, it was within the permissible range (6 log CFU/g). Furthermore, the chemical, microbial, and sensory properties in the packed fillets were significantly lower than the control (P < 0.05). The best results were observed in PLA-NC + L. casei(P < 0.05), according to the suggested acceptable limit for these properties, this treatment was able to be maintained until the end of the storage period. All in all, the use of PLA-NC + L.caseihad a positive effect on improving the quality of beluga fillets during refrigerated storage, and it can be a suitable method for the production of probiotic films.

In this study, intelligent and active film was produced based on oxidized bacterial nano cellulose (BNC) with TEMPO method containing pine tree fruit protein hydrolyzed (PFPH), and then its effect on the quality of pacific white shrimp (Litopenaeus vannamei) was investigated during a period of 16 days at refrigerator (4 ± 1 °C). For this purpose, the PFPH was hydrolyzed using alcalase enzyme and then its different concentrations (0, 0.5, 1 and 1.5%) were added to the BNC film. The shrimps were covered with the mentioned films, and their chemical (PV, TVB-N, TBA, melanisis), microbial (TVC, PTC, Pseudomonasspp., Enterobacteriaceaeand H2S-producing bacteria) and sensory characteristics were measured. According to the results, PFPH has high amounts of protein (90.21%) and amino acid included arginine (21.88%), glutamic acid (17.33%) and leucine (6.75%). The results related of shrimp showed that the effectiveness of BNC + 1.5% PFPH in preventing spoilage, inhibiting oxidation and improving physical characteristics was superior to other treatments. This optimal film significantly reduced the oxidation of fats by reflection in PV (3.71 milliequivalents/g) and TBA (1.43 mg mDA/ kg) and was able to improve the melanisis (3.33) of the treated samples with significant changes (P < 0.05). Also, the reduction of the population of microorganisms and compounds caused by microbial spoilage in the evaluated samples depended on the concentration of PFPH and with the increase in concentration, the antimicrobial properties of the films increased significantly (P < 0.05). Based on chemical, microbial and sensory acceptable amount, BNC + 1.5% PFPH were suitable for human consumption until the end of the storage period. Therefore, it seems that the BNC film containing the PFPH can be used in intelligent packaging of food products and increase the shelf life of meat products due to its antioxidant and antimicrobial properties.

In this research, the antioxidant properties of the hydrolyzed peptide of chlorella vulgaris (CVPH) with molecular weights (MW) of 3, 5, and 10 were kDa determined by using alcalase and flavourzyme enzyme, and cakes oil cake containing CVPH with a concentration of 0, 0.5 and 1% were produced and moisture, color, textural, chemical (peroxide value, acidity), microbial (Total viable count, yeast and mold) and sensory attributes (color, smell and overall acceptance) of them were evaluated during 30 days of storage at 25 °C. The results related to the characteristics of the bioactive peptide showed that the CVPH had high essential amino acids and CVPH by alcalase with a MW of 3 kDa s had the highest antioxidant activity, and this peptide was used in subsequent experiments. The results of the cake tests showed that the addition of CPVH increased the moisture content and decreased the color index of the cake, as well as CPVH reduced the oxidative and microbial spoilage of the cake during the storage period, and these treatments had a chemical and sensory permissible range until the end of the storage period. The sensory score of the treatment containing CPVH at 0.5% was higher than the treatment containing CPVH at 1%. Therefore, the use of CPVH as a natural preservative can increase the shelf life of the functional oil cake. Considering the relatively similar effect of 0.5% and 1% concentrations, as well as economic efficiency and better sensory characteristics, 0.5% can be the optimal concentration.