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The majority of acidic fruits are perishable owing to their high-water activity, which promotes microbial activity, thus exhibiting metabolic functions that cause spoilage. Along with sanitary practices, several treatments are used during processing and/or storage to inhibit the development of undesirable bacteria. To overcome the challenges caused by mild heat treatment, juice manufacturers have recently increased their involvement in developing novel non-thermal processing procedures. Ultrasonication alone or in combination with other hurdle technologies may be used to pasteurize processed fruit juices. Multifrequency ultrasound has gained popularity due to the fact that mono-frequency ultrasound has less impact on bacterial inactivation and bioactive compound enhancement of fruit juice. Here, we present and discuss the fundamental information and technological knowledge of how spoilage bacteria, specifically Alicyclobacillus acidoterrestris, assemble resistant spores and inactivate and germinate dormant spores in response to nutrient germinants and physical treatments such as heat and ultrasound. To the authors' knowledge, no prior review of ultrasonic inactivation and germination of A. acidoterrestris in fruit juice exists. Therefore, this article aims to provide a review of previously published research on the inactivation and germination of A. acidoterrestris in fruit juice by ultrasound and heat. [ABSTRACT FROM AUTHOR]

Peeling is a crucial part of the tomato deep processing procedure, and the choice of peeling method directly affects the quality of peeling. As far as the conventional peeling methods are concerned, They are still energy and water-intensive and have adverse effects on the environment. The conventional peeling methods often used in the field of tomato peeling were reviewed in this article, including manual, mechanical, chemical, or steam, and the current novel peeling methods, such as enzymatic peeling, pulse electric field peeling, infrared peeling, high-humidity hot air impingement blanching peeling, ohmic heating-assisted lye peeling, flame-catalytic infrared peeling, ultrasonic-assisted lye peeling and CO2 laser-assisted lye peeling. The mechanism, advantages and disadvantages, and applications, of different peeling methods are also summarized and analyzed. In contrast, the novel peeling method excelled in reducing the use of lye and improving the quality of peeled tomatoes. The retention of nutrients such as lycopene, ascorbic acid, and total phenols is extremely dependent on the high texture retention and low peeling loss of peeled pulp. Therefore, the mechanism of peeling and texture preservation after peeling are current research hotspots in the industry. In addition further research should accelerate the scale-up and commercial applicability of the new technology. [ABSTRACT FROM AUTHOR]

Long processing time represents a serious challenge in hot air drying since it led to high energy consumption and quality deterioration. A synergistic pretreatment of artificial perforation and alcohol maceration (PAT) was proposed in this study to improve hot air drying of garlic. Samples without pretreated, perforated, and subjected to alcohol pretreatments were used as control. The results showed that PAT pretreatment significantly reduced the drying time and energy consumed by 36.67%. Analysis showed that the mechanisms underlying the highest drying rate of PAT pretreated sample included pre-dehydration, capillary flow promotion and cell permeability enhancement. Samples pretreated with PAT exhibited the highest whiteness value, minimum shrinkage, lowest brittleness, and especially the highest content of volatile components, which is essential for its application as a spice. The antioxidant activity, total phenolics and allicin content were low in the PAT samples compared with other samples. This study provides a simple and effective approach to improve the drying of garlic. [ABSTRACT FROM AUTHOR]

This study focused on the influence of convection (at 40 °C and 50 °C) and freeze drying on functionality, structural properties and antioxidant potential of sunflower meal protein (SPm) and hydrolysate (SPHm). Likened to the respective convectively-dried isolates, lyophilized SPm and SPHm showed higher dispersibility and water binding efficacy, but lower oil binding efficacy (buttressed by surface hydrophobicity results) (p < 0.05). The alterations in sulfhydryl clusters and disulfide bridges due to convection drying (under varied temperatures) implied limited unfolding of SPm and SPHm structure and reduction in intermolecular interactions. Moreover, fluorescent intensity and deconvoluted Fourier transform infrared (FTIR) spectroscopy illustrated that convectively-dried (CD) preparations, considerably CDSPHm, possessed more flexible/movable secondary structures over freeze-dried isolates. Topographical study indicated that dehydrated SPHm-s had irregular small particles with partly destroyed/splitted micropores, suggesting disruption in the noncovalent bonds between SPHm-s molecules. Furthermore, isolates from the freeze drying process, notably lyophilized hydrolysate, showed higher antioxidative (DPPH scavenging, ABTS and reducing power) potential over the convectively-dried samples, supported by the analysis of amino acids composition. The current investigation could help the pharmacological and/or food industry to develop new therapeutic product and/or functional food from lyophilized isolates. [ABSTRACT FROM AUTHOR]

This paper aims to evaluate the impact of simultaneous tri-frequency ultrasound (20 + 40 + 60 kHz) combined vacuum (0.6 bar) assisted ethanol (75%) pretreatment on the infrared drying process, qualities (rehydration, flavor, surface color), and microbial safety of scallion stalk slices. The slices were pretreated with different methods, using ethanol, vacuum (Water + VC), vacuum-assisted ethanol (Ethanol + VC), ultrasound (Water + US), ultrasound-assisted ethanol (Ethanol + US), ultrasonic vacuum (Water + USVC), and ultrasonic vacuum-assisted ethanol (Ethanol + USVC). It was found that Ethanol + USVC pretreatment significantly reduced the drying time and showed better flavor retention and antibacterial effect, and the slices produced showed moderate rehydration ratio (7.83) and surface color change (8.94). [ABSTRACT FROM AUTHOR]