Application of microwave and ohmic heating for pasteurization of cantaloupe juice: microbial inactivation and chemical properties

Alternative flours from pulp melons (Cucumis melo L.): Seasonality influence on physical, chemical, technological parameters, and utilization in bakery product

Fresh vegetables have high water content and low acidity, so drying can extend shelf life, allowing the obtaining of alternative flours for the development of new products. The study aimed to investigate the influence of the melon harvest and off-season on the chemical composition of melon (Cantaloupe, Charentais e Honey Dew) flours and the potential application in products. The flours were evaluated for granulometry, morphology, centesimal composition, lipid and mineral content, total phenolic compound (TPC), antioxidant activity, and technological properties. Cakes containing melon flour were produced to replace wheat flour (0, 25, and 50 %) and evaluated for proximate composition, microbiology, and sensory parameters. Flours were classified as fine-grained (MESH >16), except Charentais off-season (medium - MESH 8-16, and fine-grained - MESH >16), and all presented a rough surface and minimal cell wall ruptures. The harvest homogeneously influenced the humidity, as all the off-season flours showed higher levels [17-22 %] (p < 0.05) due to weather conditions. For TPC, Cantaloupe melon flours from the harvest (CFH) [208 mg/100 g] and off-season [877 mg/100 g] stood out (p < 0.05), and the latter showed greater antioxidant potential [328 μmol TE/g]. Palmitic, linoleic, and linolenic acid stood out in all flours, and potassium for minerals (63-78 %) in the harvest and off-season. The harvest and off-season specifically influenced the flour of each variety in swelling power, water solubility, oil absorption, and emulsifying capacity. For cakes with CFH, no thermotolerant coliforms and Escherichia coli were detected, and the mesophilic count was <1.0 CFU/g. The ash, protein, lipid, and fiber contents increased proportionally to melon flour addition (p < 0.05). Sensory acceptance was high for cakes containing 25 and 50 % of CFH [82.78 % and 82.53 %], and most consumers would likely buy the products (4.04 and 3.99) (p < 0.05). The study contributed to knowledge about the seasonality effect and demonstrated the potential use of melon flour in developing new products.

Technological and health properties and main challenges in the production of vegetable beverages and dairy analogs

Lactose intolerance affects about 68-70% of the world population and bovine whey protein is associated with allergic reactions, especially in children. Furthermore, many people do not consume dairy-based foods due to the presence of cholesterol and ethical, philosophical and environmental factors, lifestyle choices, and social and religious beliefs. In this context, the market for beverages based on pulses, oilseeds, cereals, pseudocereals and seeds and products that mimic dairy foods showed a significant increase over the years. However, there are still many sensory, nutritional, and technological limitations regarding producing and consuming these products. Thus, to overcome these negative aspects, relatively simple technologies such as germination and fermentation, the addition of ingredients/nutrients and emerging technologies such as ultra-high pressure, pulsed electric field, microwave and ultrasound can be used to improve the product quality. Moreover, consuming plant-based beverages is linked to health benefits, including antioxidant properties and support in the prevention and treatment of disorders and common diseases like hypertension, diabetes, anxiety, and depression. Thus, vegetable-based beverages and their derivatives are viable alternatives and low-cost for replacing dairy foods in most cases.

Processing of verjuice by ultrasound-assisted microwave heating: An assessment on the enzyme activity retention, technological parameters, and bioactive properties

The present study evaluated the effect of ultrasonication prior to microwave heating applied at 60 °C, 70 °C, and 80 °C on the quality characteristics of verjuice. The sole microwave heating and conventional heating were also performed at the same temperature levels, and effectiveness of three different treatments were evaluated. The required treatment times were decided based on obtaining <10% pectin methylesterase (PME) activity, and ultrasound pretreatment provided the least heating durations. Turbidity, browning index, and viscosity values increased by 3.4 to 14.8-fold, 0.24 to 1.26-fold, and 9.2% to 48.0%, respectively, after all thermal treatments, while Brix values decreased by 1.4% to 15.7%. Ultrasound pretreatment revealed relatively lower browning index in all temperature levels, and almost the highest viscosity values were obtained in sonication pretreated microwave heating as compared with sole microwave and conventional heating. The minimum turbidity value (0.035) was determined in ultrasound-assisted microwave heating at 60 °C. The highest antioxidant capacity (DPPH and ABTS) values were achieved by ultrasound-assisted microwave heating (up to 4.96 and 28.4 mmol Trolox equivalent (TE)/kg, respectively) followed by microwave heating (up to 4.30 and 27.0 mmol TE/kg) and conventional heating (up to 3.72 and 26.8 mmol TE/kg). Furthermore, ultrasonication resulted in better retentions of PME residual activity during 60 days of refrigerated storage (4 °C). Ultrasound pretreatment prior to microwave heating could be a convenient approach for juice processing by reducing the required treatment time and by conserving the quality parameters.

Application of electric field treatment (EFT) for microbial control in water and liquid food

Water disinfection and food pasteurization are critical to reducing waterborne and foodborne diseases, which have been a pressing public health issue globally. Electrified treatment processes are emerging and have become promising alternatives due to the low cost of electricity, independence of chemicals, and low potential to form by-products. Electric field treatment (EFT) is a physical pathogen inactivation approach, which damages cell membrane by irreversible electroporation. EFT has been studied for both water disinfection and food pasteurization. However, no study has systematically connected the two fields with an up-to-date review. In this article, we first provide a comprehensive background of microbial control in water and food, followed by the introduction of EFT. Subsequently, we summarize the recent EFT studies for pathogen inactivation from three aspects, the processing parameters, its efficacy against different pathogens, and the impact of liquid properties on the inactivation performance. We also review the development of novel configurations and materials for EFT devices to address the current challenges of EFT. This review introduces EFT from an engineering perspective and may serve as a bridge to connect the field of environmental engineering and food science.

Combined Effect of Ultrasound and Microwave Power in Tangerine Juice Processing: Bioactive Compounds, Amino Acids, Minerals, and Pathogens

The inhibition of Escherichia coli ATCC 25922 (E. coli), Staphylococcus aureus ATCC6538 (S. aureus), Salmonella Enteritidis ATCC 13076 (S. Enteritidis), and Listeria monocytogenes DSM12464 (L. monocytogenes) is one of the main aims of the food industry. This study was the first in which the use of ultrasound and microwave power were applied to optimize the values of the bioactive components, amino acids, and mineral compositions of tangerine juice and to inhibit Escherichia coli, Staphylococcus aureus, Salmonella Enteritidis, and Listeria monocytogenes. The response surface methodology (RSM) was used to describe the inactivation kinetics, and the effects of ultrasound treatment time (X1: 12–20 min), ultrasound amplitude (X2:60–100%), microwave treatment time (X3: 30–40 s), and microwave power (X4:200–700 W). The optimum parameters applied to a 5-log reduction in E. coli were determined as ultrasound (12 min, 60%) and microwave (34 s, 700 W). The optimum condition ultrasound–microwave treatment was highly effective in tangerine juice, achieving up to 5.27, 5.12, and 7.19 log reductions for S. aureus, S. Enteritidis, and L. monocytogenes, respectively. Ultrasound–microwave treatment increased the total phenolic compounds and total amino acids. While Cu, K, Mg, and Na contents were increased, Fe and Ca contents were lower in the UM-TJ (ultrasound–microwave-treated tangerine juice) sample. In this case, significant differences were detected in the color values of ultrasound–microwave-treated tangerine juice (UM-TJ) (p < 0.05). The results of this study showed that ultrasound–microwave treatment is a potential alternative processing and preservation technique for tangerine juice, resulting in no significant quality depreciation.

How to comprehensively improve juice quality: a review of the impacts of sterilization technology on the overall quality of fruit and vegetable juices in 2010-2021, an updated overview and current issues

Fruit and vegetable juices (FVJ) are rich in nutrients, so they easily breed bacteria, which cause microbial pollution and rapid deterioration of their quality and safety. Sterilization is an important operation in FVJ processing. However, regardless of whether thermal sterilization or non-thermal sterilization is used, the effect and its impact on the overall quality of FVJ are strongly dependent on the processing parameters, microbial species, and FVJ matrix. Therefore, for different types of FVJ, an understanding of the impacts that different sterilization technologies have on the overall quality of the juice is important in designing and optimizing technical parameters to produce value-added products. This article provides an overview of the application of thermal and non-thermal technique in the field of FVJ processing over the past 10 years. The operating principle and effects of various technologies on the inactivation of microorganisms and enzymes, nutritional and functional characteristics, physicochemical properties, and sensory quality of a wide range of FVJ are comprehensively discussed. The application of different combinations of hurdle technology in the field of FVJ sterilization processing are also discussed in detail. Additionally, the advantages, limitations, and current application prospects of different sterilization technologies are summarized.

Pasteurization Modifies the Sensorial Attributes and Nutritional Profile of Orange Pulp By-Product

After orange processing, different by-products are generated, i.e., peels, seeds and pulps. The pulp is highly perishable, being an unstable food matrix that needs a preservation process to be stored and used again in the food production chain. Pasteurization is the technique of choice before aseptically packaging and storing under refrigerated conditions. In this study, the effect of pasteurization has been evaluated on the chemical, functional and sensorial profiles. Ash content decreased (p < 0.05) after the thermal treatment. Indeed, magnesium, calcium and zinc diminished, although copper was found to be higher (p < 0.05) in the pasteurized product. Total dietary fiber decreased (p < 0.05), but soluble dietary fiber raised (p < 0.05) due to hydrolysis caused by pasteurization. SDF:IDF ratio, hydration properties, and fat binding capacity were improved. Total soluble phenolic compounds remained similar but FRAP and DPPH scavenging activity decreased (p < 0.05) in the pasteurized by-product. Regarding the sensorial profile, pasteurization produced darkening, appearance of a cooked smell and an increase in bitterness. Therefore, pasteurization deteriorates the sensorial profile being able to change the attributes of an added-pasteurized-pulp juice; however, it is a good choice to preserve the orange pulp by-product to formulate food products different from juices or other beverages.

Ohmic heating application in food processing: recent achievements and perspectives

Food processing is an important operation in the food industry that converts fresh foods into final products with desirable characteristics for consumption and storage. Ohmic heating is an emerging technique for food processing that seems to be a suitable alternative to conventional heat treatment. Recently, there has been a lot of research into ohmic heating applications in processing various foods. This review highlights the findings of studies conducted in 2018–2022 on the impact of ohmic heating on the physical, chemical, and sensory properties of foodstuffs during processing. We found that this technology provides more reliable process control compared to the traditional technique, namely conventional heating. Although ohmic heating has a positive effect on the quality of foods, its efficiency is limited by certain food components, including acid and fat, that markedly affect the electrochemical attributes of foods. Therefore, to achieve optimal results, ohmic heating conditions should be set in accordance with the properties of food materials. There is a need for further in-depth studies on the performance of ohmic heating in food processing on a large, rather than a lab scale.

Conventional and Novel Technologies in the Production of Dairy Bioactive Peptides

Background

In recent years, researchers have focused on functional ingredients, functional foods, and nutraceuticals due to the rapidly increasing interest in bioactive components, especially in bioactive peptides. Dairy proteins are a rich and balanced source of amino acids and their derived bioactive peptides, which possess biological and physiological properties. In the dairy industry, microbial fermentation and enzymatic hydrolysis are promising methods for producing bioactive peptides because of their rapid efficiency, and mild reaction conditions. However, these methods utilize less raw material, take long reaction time, result in low yields, and low activity products when used alone, which pose industry to seek for novel methods as pretreatments to increase the yield of bioactive peptides.

Scope and Approach

This review emphasizes the production of peptides from the dairy proteins and discusses the potential use of novel technologies as pretreatments to conventional methods of bioactive peptides production from dairy proteins, including the mechanisms of novel technologies along with respective examples of use, advantages, limitations, and challenges to each technology.

Key Findings and Conclusion

Noteworthily, hydrolysis of dairy proteins liberate wide-range of peptides that possess remarkable biological functions to maintain human health. Novel technologies in the dairy industry such as ultrasound-assisted processing (UAP), microwave-assisted processing (MAP), and high pressure processing (HPP) are innovative and environmentally friendly. Generally, novel technologies are less effectual compared to conventional methods, therefore used in combination with fermentation and enzymatic hydrolysis, and are promising pretreatments to modify peptides’ profile, improve the yields, and high liberation of bioactive peptides as compared to conventional technologies. UAP is an innovative and most efficient technology as its mechanical effects and cavitation change the protein conformation, increase the biological activities of enzymes, and enhance enzymatic hydrolysis reaction rate.

Sensory and Physicochemical Properties and Stability of Folic Acid in a Pineapple Ready-to-Serve Beverage Fortified with Encapsulated Folic Acid

Fortification of food and beverages with folic acid is carried out frequently as a remedy to folic acid deficiency which causes serious health issues. This study was carried out to investigate the effect of incorporation of folic acid encapsulated alginate submicron particles in pineapple ready-to-serve (RTS) beverages. The encapsulation efficiency and loading capacity of the particles were 91.54 ± 0.45% and 1.02 ± 0.01%, respectively. The photostability and thermal stability studies of folic acid revealed that encapsulation poses a protective effect on folic acid and that dark and refrigerated conditions contribute to higher stability of folic acid. In this study, sensory evaluation of the RTS beverages was carried out through both ranking tests and acceptance tests using a five-point hedonic scale. The sensory panel showed the highest preference to pineapple RTS with incorporated encapsulated folic acid at a quantity of its recommended daily intake (400 µg/200 mL) before heat treatment. Shelf-life evaluations were carried out through measuring physicochemical properties, and pH, titratable acidity, and total soluble solids showed negligible or acceptable changes over two months. Folic acid degradation occurred due to heat treatment, but encapsulation in alginate submicron particles provided heat stability to folic acid. Thus, microencapsulated folic acid may be a successful carrier of folic acid which can be incorporated in beverages such as fortified pineapple RTS.

Application of Ohmic-Vacuum Combination Heating for the Processing of Senior-Friendly Food (Multiphase Food): Experimental Studies and Numerical Simulation

The popularity of senior-friendly food has been increasing as the world enters the age of an aging society. It is required that senior-friendly food products are processed with the new concept of processing techniques that do not destroy the nutritional and sensory values. Ohmic heating can be an alternative to conventional heating methods for processing senior-friendly food with retaining excellent taste and quality because of less destruction of nutrients in the food. In this study, the ohmic–vacuum combination heating system was developed to process a multiphase type of senior-friendly food. Changes in physical and electrical properties of senior-friendly model foods were investigated depending on the experimental conditions such as vacuum pressure intensity and vacuum pretreatment time. Numerical simulations based on the experimental conditions were performed using COMSOL multiphysics. The ohmic–vacuum combination heating method with agitation reduced the heating time of the model food, and non-uniform temperature distribution in model food was successfully resolved due to the effect of vacuum and agitation. Furthermore, the difference was found in the hardness of solid particles depending on the vacuum treatment time and intensity after the heating treatment. The ohmic–vacuum combination heating system appeared effective when applying for the senior-friendly foods in multiphase form. The simulation results matched reasonably well with the experimental data, and the data predicted through simulation could save the cost and time of experimentation.

[Progress of sterilization and preservation methods for allografts in anterior cruciate ligament reconstruction]

OBJECTIVE

To review the current status and progress of sterilization and preservation for allograft in anterior cruciate ligament reconstruction.

METHODS

The related literature about the sterilization and preservation of allografts in anterior cruciate ligament reconstruction was extensively reviewed and summarized.

RESULTS

There are many sterilization methods for allografts, the most commonly used method is γ-ray irradiation, but the optimal irradiation dose is still unclear. Electron beam irradiation is also available, but excessive dose is harmful to graft shaping. A combined sterilization method combining physics and chemistry methods is still being explored. Cryopreservation is the most commonly used method of preservation. In order to reduce the influence of crystals, the principle of "slow cooling and rapid rewarming" should be adhered to as far as possible.

CONCLUSION

The processing methods of allograft can affect the effectiveness of anterior cruciate ligament reconstruction. The clinical doctors should consider the sterilization and preservation methods in practice.