Aqueous ozone sanitization of whole peeled onion: Process optimization and evaluation of keeping quality during refrigerated storage

Multimode ultrasonic-assisted decontamination of fruits and vegetables: A review

Fruits and vegetables (F&V) are a significant part of our diet consumption. Microbial and pesticide residues are the predominant safety hazards of F&V consumption. Ordinary water washing has a very limited effect on removing microorganisms and pesticide residues and requires high water usage. Ultrasound, as an environmentally friendly technology, shows excellent potential for reducing microbial contamination and pesticide residue. This paper summarizes the research on ultrasound application in F&V washing, including the removal of microbial and pesticide residues and the comprehensive effect on their physicochemical characteristics. Furthermore, multimode ultrasonic-assisted techniques like multi-frequency and sequential ultrasound, combined with novel and conventional methods, can enhance the ultrasound-based effect and be more effective and sustainable in preventing F&V from microbial contamination. Overall, this work explicitly establishes the background on the potential for ultrasound cleaning and disinfection in the food industry as a green, effective, and ultimate method of preventing foodborne illnesses.

Application of emerging thermal and nonthermal technologies for improving textural properties of food grains: A critical review

Emerging nonthermal and thermal food processing technologies are a better alternative to conventional thermal processing techniques because they offer high-quality, minimally processed food. Texture is important in the food industry because it encompasses several product attributes and plays a vital role in consumer acceptance. Therefore, it is imperative to analyze the extent to which these technologies influence the textural attributes of food grains. Physical forces produced by cavitation are attributed to ultrasound treatment-induced changes in the conformational and structural properties of food proteins. Pulsed electric field treatment causes polarization of starch granules, damaging the dense outer layer of starch granules and decreasing the mechanical strength of starch. Prolonged radio frequency heating results in the denaturation of proteins and gelatinization of starch, thus reducing binding tendency during cooking. Microwave energy induces rapid removal of water from the product surface, resulting in lower bulk density, low shrinkage, and a porous structure. However, evaluating the influence of these techniques on food grain texture is difficult owing to differences in their primary operation mode, operating conditions, and equipment design. To maximize the advantages of nonthermal and thermal technologies, in-depth research should be conducted on their effects on the textural properties of different food grains while ensuring the selection of appropriate operating conditions for each food grain type. This article summarizes all recent developments in these emerging processing technologies for food grains, discusses their potential applications and drawbacks, and presents prospects for future developments in food texture enhancement.

The Use of Ozone Technology to Control Microorganism Growth, Enhance Food Safety and Extend Shelf Life: A Promising Food Decontamination Technology

The need for microorganism control in the food industry has promoted research in food processing technologies. Ozone is considered to be a promising food preserving technique and has gained great interest due to its strong oxidative properties and significant antimicrobial efficiency, and because its decomposition leaves no residues in foods. In this ozone technology review, the properties and the oxidation potential of ozone, and the intrinsic and extrinsic factors that affect the microorganism inactivation efficiency of both gaseous and aqueous ozone, are explained, as well as the mechanisms of ozone inactivation of foodborne pathogenic bacteria, fungi, mould, and biofilms. This review focuses on the latest scientific studies on the effects of ozone in controlling microorganism growth, maintaining food appearance and sensorial organoleptic qualities, assuring nutrient contents, enhancing the quality of food, and extending food shelf life, e.g., vegetables, fruits, meat, and grain products. The multifunctionality effects of ozone in food processing, in both gaseous and aqueous form, have promoted its use in the food industries to meet the increased consumer preference for a healthy diet and ready-to-eat products, although ozone may present undesirable effects on physicochemical characteristics on certain food products at high concentrations. The combined uses of ozone and other techniques (hurdle technology) have shown a promotive future in food processing. It can be concluded from this review that the application of ozone technology upon food requires increased research; specifically, the use of treatment conditions such as concentration and humidity for food and surface decontamination.

A chemometric approach to evaluate the effects of probe-type ultrasonication on the enzyme inactivation and quality attributes of fresh amla juice

The enzymatic browning induced in amla juice due to the high activity of polyphenol oxidase (PPO) and peroxidase (POD) is one of the critical issues faced by the industry. The present study assessed the suitability of non-thermal, high-intensity ultrasound (US) on the inactivation of PPO and POD in fresh Indian Gooseberry juice. Ultrasonic waves, using a 6 mm titanium alloy probe were irradiated in the juice at a maximum power of 455 W and frequency of 20 kHz. The subsequent effects on biochemical attributes were studied using response surface methodology. Inactivation rates of 90.72 % and 73.18 %, respectively, for PPO and POD enzymes, were observed at the highest US intensity and exposure time. Numerical optimisation using the three-factor, three-level Box-Behnken design suggested that an optimum process at 70 % (energy density: 1610 Wcm^-2) pulsed at 5 s on and 5 s off for 7 min 30 s resulted in PPO and POD inactivation of the order of 76.42 % and 64.57 % respectively. At these experimental conditions, the optimized levels of biochemical attributes i.e., ascorbic acid (738.50 mg/100 mL), total phenols (17.10 mg/mL), DPPH antioxidant activity (58.47 %), tannins (7.11 µg/mL), colour change (ΔE = 9.04) and flavonoids (6.14 mg/mL) were achieved. The overall statistical models were significant for all the responses except for reducing sugars. Furthermore, the approximation equations for individual responses indicated that the goodness of fit was adequate (R² > 0.90). The results suggested that ultrasound is a suitable processing technique for amla juice stabilisation compared to thermal treatments that result in the loss of quality.

Understanding the effects of ultrasound processng on texture and rheological properties of food

The demand for the production of high quality and safe food products has been ever increasing. Consequently, the industry is looking for novel technologies in food processing operations that are cost-effective, rapid and have a better efficiency over traditional methods. Ultrasound is well-known technology to enhance the rate of heat and mass transfer providing a high end-product quality, at just a fraction of time and energy normally required for conventional methods. The irradiation of foods with ultrasound creates acoustic cavitation that has been used to cause desirable changes in the treated products. The technology is being successfully used in various unit operations such as sterilization, pasteurization, extraction, drying, emulsification, degassing, enhancing oxidation, thawing, freezing and crystallization, brining, pickling, foaming and rehydration, and so forth. However, the high pressure and temperature associated with the cavitation process is expected to induce some changes in the textural and rheological properties of foods which form an important aspect of product quality in terms of consumer acceptability. The present review is aimed to focus on the effects of ultrasound processing on the textural and rheological properties of food products and how these properties are influenced by the process variables.

Optimization and Effect of Water Hardness for the Production of Slightly Acidic Electrolyzed Water on Sanitization Efficacy

Slightly acidic electrolyzed water (SAEW) has been recently proposed as a novel promising sanitizer and cleaner in the agricultural and food industries. However, several factors, including water hardness, were considered to strongly affect the physical properties and sanitization efficacy of SAEW. To study the effect of water hardness on the SAEW production, we evaluated the production properties and sanitization effect of SAEW, which was generated from water sources in 16 representatively geographical locations of South Korea. The results showed that the hardness of water sources from Kangwon-do, Jeollanam-do, and Daegu was 22-41 ppm; that from Busan, Gyeongnam-do, Gwangju Bukgu was 80-443 ppm, and that from seven other locations was 41-79 ppm. SAEW is produced from water hardness less than 50 ppm and greater than 80 ppm was beyond the accepted pH range (5.0-6.5). Notably, high-hardness water (>80 ppm) containing 5% HCl could be used to produce SAEW with accepted pH. The SAEW generated from low-hardness water with additions of 2% HCl and 2 M NaCl at 7 A showed accepted pH and higher germicidal effect. Furthermore, SAEW with the available chlorine concentration of 27-41 mg/L for 1 min was sufficient to completely inactivate non-spore-forming foodborne pathogens. Sanitization efficacy was not markedly affected by storage conditions for SAEW at 40 ppm. Our results demonstrated that the degree of water hardness is an important factor in the production of SAEW, which would provide a foundation for commercial application of SAEW.