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Prepared dishes are increasingly popular convenience food that can be eaten directly from hygienic packaging by heating. Physics field (PF) is food processing method built with physical processing technology, which has the characteristics of high efficiency and environmental safety. This review focuses on summarizing the application of PFs in prepared dishes, evaluating and comparing PFs through quality changes during processing and storage of prepared dishes. Currently, improving the quality and extending the shelf life of prepared dishes through thermal and non-thermal processing are the main modes of action of PFs. Most PFs show good potential in handing prepared dishes, but may also react poorly to some prepared dishes. In addition, the difficulty of precise control of processing conditions has led to research mostly at the laboratory stage, but as physical technology continues to break through, more PFs and multi-physical field will be promoted for commercial use in the future. This review contributes to a deeper understanding of the effect of PFs on prepared dishes, and provides theoretical reference and practical basis for future processing research in the development of various enhanced PFs. Prepared dishes are classified according to the degree of processing. Physical fields are classified and described according to different physical methods. The application of efficient physical fields to prepared dishes is described. The application of efficient physical fields and its combination in food processing is prospected. [ABSTRACT FROM AUTHOR]

Although complex coacervation could improve the water solubility, thermal stability, bioavailability, antioxidant activity and antibacterial activity of essential oils (EOs). However, some wall materials (such as proteins and polysaccharides) with water solubility and hydrophobic nature limited their application in complex coacervation. In order to improve the properties of EO complex coacervates, some efficient physical field technology was proposed. This paper summarizes the application and functional properties of EOs in complex coacervates, formation and controlled-release mechanism, as well as functions of EO complex coacervates. In particular, efficient physical field technology as innovative technology, such as high pressure, ultrasound, cold plasma, pulsed electric fields, electrohydrodynamic atomization and microwave technology improved efficient and quality attributes of EO complex coacervates are reviewed. The physical fields could modify the gelling, structural, textural, emulsifying, rheological properties, solubility of wall material (proteins and polysaccharides), which improve the properties of EO complex coacervates. Overall, EOs complex coacervates possess great potential to be used in the food industry, including high bioavailability, excellent antioxidant capacity and gut microbiota in vivo, masking the sensation of off-taste or flavor, favorable antimicrobial capacity. [ABSTRACT FROM AUTHOR]

With the increase of people's awareness of food safety, it is crucial to find natural and green antimicrobial agents to replace traditional antimicrobial agents. Essential oils of spices (SEOs) are low toxicity or nontoxic, which exhibited antioxidants and antimicrobial activity according to many in vitro and in situ experiments. Spices are widely available and low cost as a plant raw material for the extraction of SEOs. This review summarized highly efficient extraction techniques for SEOs, such as physical field assisted extraction technology, supercritical fluid extraction, and biological-based techniques. Furthermore, purification of SEOs and components were also recapitulated. Purification techniques of SEOs improve their utilization value due to the increased content of bioactive components. Finally, the review concentrated on the applications of SEOs in food industry, including food preservation, food active packaging by means of films or coatings, antioxidant properties. In addition, addressing the problem of unstability of SEOs and its role to inhibit the pathogenic bacteria, the encapsulation of SEOs for use in the food industrial sectors reduces the safety risk to human health. [ABSTRACT FROM AUTHOR]

The present study was undertaken to determine the effect of natural colorants and combination with select chemical products on anthocyanins, total phenolics (TPC) and total flavonoids content (TFC) of rose powder, and on the stability of anthocyanins (ACNs) during storage. Moreover, the color property of rose juice in holding period of 0-1hr at room temperature was also studied. Rose powder was mixed with three chemicals (citric CA; ascorbic AA; tartaric acid TTA) and natural colorants powder (Anthocyanin; Hibiscus; food-grade Vitamin-C) at different levels viz. 0.1%, 1%, 5% and 10% (w/w), respectively. AA addition at 1% retained the highest anthocyanins content among the chemical groups, while Hibiscus 1% addition resulted in the highest amount of anthocyanins retention (56.02 ± 1.86 mg/g, cyanidin 3- glucoside equivalent). In addition, the degradation rate of anthocyanins increased significantly with storage time and temperature except for 1% Hibiscus flowers at 25 °C. TPC of chemical additions showed no significant change in rose powder. However, natural colorant additions resulted in distinct TPC and TFC compared to the control sample except for Vitamin-C addition. All the additive-mixed samples exhibited a lighter color and lowered the redness value after a period of time. [ABSTRACT FROM AUTHOR]

Fresh foods such as fruits, vegetables, grains, nuts, and meats are generally rich in water and are susceptible to microbial contamination. Drying and dehydration processes can reduce water content, but low water activity foods may not be microbiologically safe. Several novel drying techniques have demonstrated varying degrees of effectiveness in microbial inactivation, including supercritical CO2 drying, low-pressure superheated steam drying, microwave drying, radio frequency drying, infrared drying, vacuum drying, freeze drying, etc. Some typical microorganisms used as indicators of microbial inactivation including natural present microorganisms (e.g., mesophilic bacteria and their spores, yeast and mold) and various pathogens (e.g., Escherichia coli O157:H7, Listeria monocytogenes and Salmonella spp.). This paper reviewed novel drying techniques for controlling microbial contamination of fresh foods and analyzed their advantages/disadvantages and microbial inactivation capabilities. These novel drying techniques have the potential to ensure microbiological safety during drying and have the prospect of shortening the food processing chain by integrating drying and sterilization/decontamination into the same process. [ABSTRACT FROM AUTHOR]

Presence of pesticide residues on fruits and vegetables is a serious safety issue for consumers. Efforts are being made to utilize drying technology to turn fruits and vegetables with high pesticide residues into dehydrated products with minimal or no pesticide residues are clearly conducive to ensuring safety and international fresh food commodity trade. This paper attempts to summarize the latest developments in drying technologies and pre-drying treatments for controlling pesticide residues in fruits and vegetables, with emphasis on sun-, oven-, freezing-, vacuum-, and microwave-drying technology, as well as non-thermal pretreatment methods such as ultrasound, non-thermal plasma (NTP), pulsed electric field (PEF), high hydrostatic pressure (HHP), and irradiation. [ABSTRACT FROM AUTHOR]

Deep-frying is the century-old and the most common cooking process which is still being used to prepare a variety of food products in industrial and domestic scales. Compared to other cooking processes, frying produces some distinctive flavor characteristics, but other undesirable and unacceptable characteristics to consumers are also originated during frying. Researchers have taken various technical approaches for reducing the oil content of fried products without compromising product quality. This review discusses some recently developed frying techniques which could improve the product quality, and advance frying efficiency, to save energy cost. Some modified method of alternative frying technologies used by the researchers are vacuum frying, microwave frying, microwave-assisted vacuum frying, radiant frying, ultrasound treated frying, air frying or their combinations. In this review, we aim to give a detailed insight into some specific aspects of new deep-frying practices and pretreatments for the quality maintenance of fried products highlighting their novelty and efficiency. [ABSTRACT FROM AUTHOR]

Flavor changes of garlic during drying process were monitored using LF-NMR combined with partial least squares (PLS) and back-propagation artificial neural network (BP-ANN). Results show that with elapsed drying time, the free water (A23) and total moisture content (A) of garlic decrease with different drying conditions. Correspondingly, the sulfide of main flavor components in garlic was significantly reduced, but alcohol and acid components increased slightly and the overall aromatic flavor showed a downward trend, which was consistent with the GC-MS volatile component detection results. Electronic nose sensors S2, S5, S8, S10 were determined as feature sensors by principal component analysis (PCA) and linear discriminant analysis (LDA). The univariate linear model of NMR parameters and electronic nose characteristic sensors show high correlation. Furthermore, ANN and PLS garlic flavor prediction model were established, although the PLS model was not as good as the BP-ANN model (RP2 of 0.9713 and 0.9975) to monitor flavor changes, it also yields relatively accurate prediction performance with RP2 of 0.9418 and 0.9633 for mid-shortwave infrared drying and microwave vacuum drying, respectively. [ABSTRACT FROM AUTHOR]

The effect of ultrasound pretreatments at different power levels on drying time and quality parameters of freeze-dried carrot slices was studied. The drying time was significantly reduced (p < 0.05) for both traditional freeze-drying (FD) and infrared freeze-drying (IRFD) with ultrasound pretreatment; the reduction was more evident for IRFD. The drying time was reduced from 698 min to 593 min for FD, whereas it was reduced from 577 min to 459 min for IRFD. The higher ultrasonic power seriously destroyed the cell wall, resulting into more void structure. At ultrasonic power of 150 W, 240 W, and 300 W, the drying time was reduced by 20.7%, 23.7%, and 22.6%, respectively, during IRFD, when compared with FD. The retention of β-carotene was significantly higher (p < 0.05) at 240 W and 300 W; the value was, respectively, 22.7% and 32.0% higher than the control value. The LF-NMR study showed the different states of water and the increase in ultrasound power caused the increase in the relaxation time for free water, indicating more easily drying. However, there was no significant difference (p > 0.05) in color, texture, and sensory properties between FD and IRFD samples. [ABSTRACT FROM AUTHOR]

The frying kinetics (moisture loss rate and oil uptake rate) of an innovatively designed ultrasound and microwave-assisted vacuum frying (UMVF) system was investigated and the possibility of UMVF for reducing the nutrient losses during frying were evaluated in this work. The white button mushroom was the tested sample in this study. The chips were fried into two frying temperatures (80 and 90 °C), three different frying processes, vacuum frying (VF), microwave vacuum frying (MVF), and UMVF at a fixed vacuum pressure (12 ± 1 kPa). The first-order kinetic model was used for the mass transfer (moisture loss and oil uptake). Concerning the fitting performances, the logarithmic model and Pedrischi model showed the best-fitted model for moisture loss rate and for oil uptake respectively. Combining ultrasound and microwave in VF, the calculated moisture diffusivity rate was increased from 1.599 × 10−10 to 2.769 × 10−10 m2/s and oil uptake rate was decreased from 0.0121 to 0.0059 s−1. Total oil content (TOC) of fried mushroom chips (FMC) was quantified into two segments, surface oil (SO), and structure oil (STO) at a different time interval during frying. STO had the highest fraction of TOC and results revealed that UMVF had significantly low level of STO, which means UMVF helped to reduce the oil absorption during frying. In order to consider the nutrient retention values, UMVF exhibited the highest nutrition retention values. The exponential spectra of LF-NMR clearly revealed the water–oil distribution of FMC. [ABSTRACT FROM AUTHOR]

Rose flower chips were produced by freeze drying (FD), pulse spouted vacuum-microwave freeze drying (PSVMFD), vacuum-microwave freeze drying (VMFD), and microwave-assisted vacuum drying (MVD). Drying time, color attributes (L*, a*, b* and h), flavor, texture, Vitamin C, flavonoids content, shrinkage value, DPPH radical scavenging capacity, and microstructure were compared. Results showed that MVD was the fastest (120 min) method of drying and FD was the slowest (560 min) method to achieve the target moisture content (under 5%). Considering product quality, FD samples exhibited the highest vitamin C (2.40 ± 0.14 mg/100 g) and flavonoids content (88.33 ± 0.22 mg/100 g), with the strongest DPPH radical scavenging capacity, followed by PSVMFD samples. Additionally, FD samples showed the lowest shrinkage (3.89 ± 0.01%) followed by PSVMFD samples (15.02 ± 0.02%) whereas the MVD chips had the highest shrinkage (50.12 ± 0.12%). FD and PSVMFD samples exhibited loose porous structure, while VMFD and MVD samples showed more compact structure. Considering the drying time and product quality comprehensively, PSVMFD was a novel and promising drying method to produce high quality rose flower chips. [ABSTRACT FROM AUTHOR]

A mixed solid matrix of the depolymerized pectin (DP) and rice protein (RP) were investigated to improve the antibacterial activity of star anise essential oil (SAEO) through microencapsulation. The encapsulation was undertaken via electrostatic complexation method followed by spray drying. Under the optimized conditions, SAEO microcapsules with 92.2 % encapsulation efficiency was acquired at 3:2 of DP-to-RP, 1:3 of DP-to-SAEO and pH 4.0. DP-RP/SAEO microcapsules exhibited a spherical-shaped particle with smaller particle size, and sustained release. FTIR and morphology analysis confirmed that SAEO was successfully encapsulated in the solid matrix of microcapsules. DP-RP/SAEO microcapsules caused the destruction of cytomembranes and reduction of membrane proteins, which led to the alteration of cell membrane fluidity and integrity. Meanwhile, DP-RP/SAEO microcapsules repressed the key enzyme in tricarboxylic acid (TCA) and Hexose monophosphate pathway (HMP) cycle pathway of E. coli , S. aureus. The application experiments indicated DP-RP/SAEO microcapsules can effectively control the growth of E. coli and S. aureus in crab meatballs. • Depolymerized pectin (DP) showed lower molecular weight and excellent properties. • Star anise essential oil (SAEO) was encapsulated by DP and rice protein. • SAEO microcapsules showed good morphology and high encapsulation ability. • SAEO microcapsules exhibited excellent antibacterial activity. • SAEO exhibited good application effect in crab meatballs. [ABSTRACT FROM AUTHOR]

The mixture of garlic essential oil (GEO), ginger essential oil (GIEO) and litsea cubeba essential oil (LCEO) was prepared and its effect on the antibacterial activity of E. coli , S. aureus and P. aeruginosa , as well as properties of ready-to-eat pakchoi during storage were assessed. GEO, GIEO or LCEO treatment significantly enhanced the accumulation of reactive oxygen species (ROS) levels, resulting in disruption of the permeability of cell membrane, the leakage of cytoplasmic contents, and the alteration of the secondary structure of bacterial proteins. Meanwhile, GEO, GIEO or LCEO treatment repressed the key enzyme in tricarboxylic acid (TCA) and Hexose monophosphate pathway (HMP) cycle of E. coli , S. aureus and P. aeruginosa. Essential oil treatments (p < 0.05) could significantly prolong the shelf life of pakchoi, total bacterial count (TBC) values and chlorophyll content of GEO/GIEO/LCEO sample were 3.47 log cfu/g and 0.82 mg/g, respectively, after storage for 7 days. E. coli , S. aureus and P. aeruginosa counts in GEO/GIEO/LCEO samples decreased by 56.76 %, 70.10 %, 73.95 % compared to CK (no essential oil) samples. The comprehensive results from the sensory (flavor and color) and microbial analysis (especially TBC) showed that GEO/GIEO/LCEO could extend the shelf life of ready-to-eat pakchoi from 4 d to 7 d. As compared with GEO, GIEO or LCEO individually, the combination of GEO, GIEO and LCEO exhibited synergistic effect and more pronouncedly antibacterial activity to improve quality of ready-to-eat pakchoi. • Effects of GEO/GIO/LCEO on the quality of ready-to-eat pakchoi was investigated. • GO/GEO/LCEO inhibit bacterial growth by destroying membrane integrity. • GO/GEO/LCEO subdued microbial survival and prolonged shelf life of pakchoi. • GO/GEO/LCEO produced better-quality characteristics than single essential oil. [ABSTRACT FROM AUTHOR]