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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]

Converting biomass to produce renewable chemicals is one of the significant ways to realize the development of green chemistry and sustainable chemical industry. As the main component of lignocellulosic biomass, lignin is the most abundant natural polyphenol. Its unique phenolic properties and high carbon content make it potentially exploited. Biomass lignin depolymerization can be divided into thermochemical, chemical catalysis, electrocatalysis, and biological depolymerization methods. In this review, the catalytic reaction systems involved in different methods of lignin depolymerization were extensively described from various aspects, and the degradation products and reaction mechanisms were discussed and analyzed. The effects of novel green-deep eutectic solvents on biomass lignin depolymerization were reviewed in particular. Each method of biomass lignin depolymerization has its own advantages and disadvantages. The different sources of biomass lignin should be selected objectively according to its compositional structure, so as to achieve efficient biomass lignin depolymerization. In addition, the challenges and future development prospects of biomass lignin depolymerization were also discussed. [ABSTRACT FROM AUTHOR]

For health and safety concerns, traditional high‐calorie sweeteners and artificial sweeteners are gradually replaced in food industries by natural and low‐calorie sweeteners. As a natural and high‐quality sugar substitute, steviol glycosides (SvGls) are continually scrutinized regarding their safety and application. Recently, the cultivation of organic stevia has been increasing in many parts of Europe and Asia, and it is obvious that there is a vast market for sugar substitutes in the future. Rebaudioside A, the main component of SvGls, is gradually accepted by consumers due to its safe, zero calories, clear, and sweet taste with no significant undesirable characteristics. Hence, it can be used in various foods or dietary supplements as a sweetener. In addition, rebaudioside A has been demonstrated to have many physiological functions, such as antihypertension, anti‐diabetes, and anticaries. But so far, there are few comprehensive reviews of rebaudioside A. In this review article, we discuss the physicochemical properties, metabolic process, safety, regulatory, health benefits, and biosynthetic pathway of rebaudioside A and summarize the modification methods and state‐of‐the‐art production and purification techniques of rebaudioside A. Furthermore, the current problems hindering the future production and application of rebaudioside A are analyzed, and suggestions are provided. [ABSTRACT FROM AUTHOR]

Recent researches show that using seed sprouts in the diet as a healthy food not only being a good source of basic nutrients but also contain chemical compounds with health-promoting properties. This study aimed to evaluate the effect of China clover seeds soaking in NaCl (0, 1000 and 2000 ppm) solution and ultrasound irradiation levels (0, 20, 28 and 40 kHz) and their interactions on clover seed sprouting; sprout character, chemical composition and protein quality of clover sprouts. The obtained result revers that China clover seed sprouting increased the protein content in sprout samples. Using NaCl solution in combination with ultrasound seed priming also resulted in better sprout characters, mineral content, total essential amino acids (TEAA), protein efficient ratio (PER), essential amino acid index (EAAI), biological value (BV) and nutritional index (NI) compared with deionized water control. Essential amino acid methionine (Precursor of ethylene biosynthesis) increased in clover sprout with increasing NaCl concentration and inhibit clover sprout growth. Salicylic acid a phytochemical phenolic compound increased with increasing pretreatment ultrasound frequency levels which inhibited ethylene production. Therefore, Ultrasound with NaCl seed priming could be a simple approach for enhancing tolerance to salinity stress in China clover. Moreover, clover sprouting influenced the protein content and quality of sprouts as a functional food. [ABSTRACT FROM AUTHOR]

Cherry tomato fruits were treated with three dual‐frequency ultrasound (US) at different temperature and time. The three treatment variables, that is, dual‐frequency US, temperature, and time were optimized with the aid of response surface methodology (RSM). About 20/40 kHz, 52°C, and 6 min were the optimum condition obtained for total bacteria count (TBC, 1.08 log cfu/g), firmness (15.90 N), and total phenolic content (TPC, 34.34 mg GAE/100 g). All the linear relations of the treatment variables showed a significantly negative and positive effect on the TBC and TPC, respectively, while positive significant effects were obtained for some of the relations of the firmness. Hence dual‐frequency sonication is effective for microbial safety and maintaining the quality of cherry tomato. Also, RSM was found to be a useful tool in setting and optimizing the variables responsible for sonication treatment. Practical applications: Thermosonication (ultrasonication and heat) has been applied toward improving the microbial safety and nutritional quality of vegetables and fruit. However, factors such as power, frequency, time, temperature, etc. determine the efficiency of its operation. Controlling these factors is difficult and therefore requires a robust and efficient optimization tool in determining their effects (individual and interactions) on food during treatment. In this study, response surface methodology provides the solution in settling and optimizing the variables for the sonication treatment. Besides, the remarkable result obtained in this work offers an alternative to the combined use of ultrasound and chemical in food industries. [ABSTRACT FROM AUTHOR]