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Hawthorn belongs to the Crataegus genus of the Rosaceae family and is an important medicinal plant. Due to its beneficial effects on the cardiovascular system and its antioxidant and antimicrobial activity hawthorn has recently become quite a popular herbal medicine in phytotherapy and food applications. In this study, physicochemical characterization (color parameters, pH, titratable acidity, total soluble solids, soluble carbohydrate, total carotenoid, total phenols, and flavonoid contents), antioxidant activity (by ferric-reducing antioxidant power, FRAP assay), and quantification of some individual phenolic compounds of fruits of 15 samples of different hawthorn species (Crataegus spp.) collected from different regions of Iran were investigated. According to findings, the total phenols, total flavonoid content, and antioxidant activity were in the range of 21.19–69.12 mg gallic acid equivalent (GAE)/g dry weight (dw), 2.44–6.08 mg quercetin equivalent (QUE)/g dw and 0.32–1.84 mmol Fe++/g dw, respectively. Hyperoside (0.87–2.94 mg/g dw), chlorogenic acid (0.06–1.16 mg/g dw), and isoquercetin (0.24–1.59 mg/g dw) were found to be the most abundant phenolic compounds in the extracts of hawthorn fruits. The considerable variations in the antioxidant activity and phenolic compounds of hawthorn species were demonstrated by our results. Hence, the evaluation of hawthorn genetic resources could supply precious data for screening genotypes with high bioactive contents for producing natural antioxidants and other phytochemical compounds valuable for food and pharma industries.

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The present study was conducted to assess the impact of chitosan coating (1%) containing Artemisia fragrans essential oil (500, 1000, and 1500 ppm) as antioxidant and antimicrobial agent on the quality properties and shelf life of chicken fillets during refrigerated storage. After packaging meat samples, physicochemical, microbiological, and organoleptic attributes were evaluated at 0, 3, 6, 9, and 12 days at 4 °C. The results revealed that applied chitosan (CH) coating in combination with Artemisia fragrans essential oils (AFEOs) had no significant (p < 0.05) effects on proximate composition among treatments. The results showed that the incorporation of AFEOs into CH coating significantly reduced (p < 0.05) pH, thiobarbituric acid reactive substances (TBARS), and total volatile base nitrogen (TVB-N), especially for 1% CH coating + 1500 ppm AFEOs, with values at the end of storage of 5.58, 1.61, and 2.53, respectively. The coated samples also displayed higher phenolic compounds than those obtained by uncoated samples. Coated chicken meat had, significantly (p < 0.05), the highest inhibitory effects against microbial growth. The counts of TVC (total viable counts), coliforms, molds, and yeasts were significantly lower (p < 0.05) in 1% CH coating + 1500 ppm AFEOs fillets (5.32, 3.87, and 4.27 Log CFU/g, respectively) at day 12. Organoleptic attributes of coated samples also showed the highest overall acceptability scores than uncoated ones. Therefore, the incorporation of AFEOs into CH coating could be effectively used for improving stability and shelf life of chicken fillets during refrigerated storage.

The effects of green tea (GTE), stinging nettle (SNE) and olive leaves (OLE) extracts on physicochemical, microbiological, texture and sensory properties of Frankfurter type sausage were investigated during 45 days of storage at 4C. Results indicated that pH, aw value, phenolic compounds and color values (L* and a* values) decreased during storage. Samples incorporated with 500 ppm GTE showed the lowest TBARS value compared to SNE, OLE and control sausage. Plant extracts reduced the count of total viable bacteria, mold and yeast by at least 2 log cfu/g. The addition of OLE increased significantly the maximum compression force compared with other samples. Sausage incorporated with SNE had the highest sensory score regarding flavor, freshness odor and overall acceptability. Based on the results, sausage incorporated with plant extracts could have a significant impact to improve quality benefits, color stability and shelf life of Frankfurter type sausage. Practical Application Food decay by spoilage microorganisms and chemical activities causes considerable economic losses and constitutes a health risk for consumers. Although chemical preservatives can effectively be used in meat products to control spoilage, foodborne pathogenic microorganisms and lipid oxidation, whereas there are significant concerns related to their toxicological aspects. Plant extracts are rich in potentially bioactive compounds, antimicrobial and antioxidant ingredients. The addition of natural ingredients such as green tea, stinging nettle and olive leaves extracts to Frankfurter type sausage could provide functional components to improve the healthier properties, sensory attributes and shelf life extension of novel meat products.

Pulsed electric field (PEF) treatment consists of exposing food to electrical fields between electrodes within a treatment chamber, which can improve the preservation of fresh-like products such as milk. Although several studies support the use of PEF technology to process milk at low temperature, these studies reported microbial reductions of around 3 log 10 cycles and also indicated a limited impact of PEF on some endogenous and microbial enzymes. This scenario indicates that increasing the impact of PEF on both enzymes and microorganisms remains a major challenge for this technology in milk processing. More recently, combining PEF with mild heating (below pasteurization condition) has been explored as an alternative processing technology to enhance the safety and to preserve the quality of fresh milk and milk products. Mild heating with PEF enhanced the safety of milk and derived products (3 log 10 -6 log 10 cycles reduction on microbial load and drastic impact on the activity enzymes related to quality decay). Moreover, with this approach, there was minimal impact on enzymes of technological and safety relevance, proteins, milk fat globules, and nutrients (particularly for vitamins) and improvements in the shelf-life of milk and selected derived products were obtained. Finally, further experiments should consider the use of milk processed by PEF with mild heating on cheese-making. The combined approach of PEF with mild heating to process milk and derived products is very promising. The characteristics of current PEF systems (which is being used at an industrial level in several countries) and their use in the liquid food industry, particularly for milk and some milk products, could advance towards this strategy.

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