Quality characteristics of the processed dates vinegar under influence of ultrasound and pulsed electric field treatments

Optimizing physicochemical properties, antioxidant potential, and antibacterial activity of dry ginger extract using sonication treatment

This research paper focused on enhancing the physico-chemical attributes, antioxidant capacity, and antibacterial effectiveness of dry ginger extract through sonication as an assistant extraction treatment. Ginger, resulting from the rhizome of Zingiber officinale Roscoe, is known for its culinary and medicinal uses outstanding to its antioxidant and antimicrobial possessions from phenolic acids and flavonoids. The study explored the use of sonication as an assistant extraction method and found that it significantly augmented the total phenolic content of the ginger extract by 28 % compared to traditional extraction methods, reaching 10.55 ± 1.50 mg GAE/g, DW. The research assessed the physicochemical belongings, antioxidant action, and antibacterial possibility of the sonicated ginger extract. The sonicated extract exhibited scavenging activity against the DPPH radical of 56.0 %. Pearson correlation investigation revealed a strong confident correlation between the phenolic content and antioxidant activity (r = 0.92, p < 0.01), as well as volatile compounds exhibited a moderate confident correlation with antibacterial action (r = 0.67, p < 0.05). The sonicated ginger extract also demonstrated potent antibacterial action, preventing the growth of both Gram-positive and Gram-negative bacteria. These findings contribute to the development of more efficient methods for extracting phenolic from ginger and provide insights into the relationships between phenolic and bioactive properties.

Optimization of sensory properties of ultrasound-treated strawberry vinegar

Vinegar is renowned for its benefits to human health due to the presence of antioxidants and bioactive components. Firstly, this study optimized the production conditions of ultrasound-treated strawberry vinegar (UT-SV), known for its high consumer appeal. The sensory properties of UT-SV were optimized by response surface methodology (RSM) to create the most appreciated strawberry vinegar. Secondly, various quality parameters of conventional strawberry vinegar (C-SV), UT-SV, and thermally pasteurized strawberry vinegar (P-SV) samples were compared. RSM was employed to craft the best strawberry vinegar based on consumers ratings of UT-SV. Sensory characteristics, bioactive values, phenolic contents, and organic acid contents of C-SV, UT-SV, and P-SV samples were assessed. Through optimization, the ultrasound parameters of the independent variables were determined as 5.3 min and 65.5 % amplitude. The RSM modeling levels exhibited high agreement with pungent sensation at 98.06 %, aromatic intensity at 98.98 %, gustatory impression at 99.17 %, and general appreciation at 99.26 %, respectively. Bioactive components in UT-SV samples increased after ultrasound treatment compared to C-SV and P-SV samples. Additionally, the amount of malic acid, lactic acid, and oxalic acid increased after ultrasound treatment compared to C-SV samples. Ultimately, UT-SV with high organoleptic properties was achieved. The ultrasound treatment positively impacted the bioactive values, phenolic and organic acid content, leading to the development of a new and healthy product.

Innovative date syrup processing with ohmic heating technology: Physiochemical characteristics, yield optimization, and sensory attributes

The present study aimed to investigate the application of the ohmic heating (OH) technique in the production of date syrup from the date fruit of the Sukkary variety at different electric field strengths (EFS) (9, 10, and 11 V/cm). The results were compared to the conventional heating method (CH). The response surface methodology was used to optimize yield. The results showed that the time to reach the boiling point of dates and water mixture using OH was less than the CH by 80% for extracting and 900% for evaporation. In addition, the productivity of date syrup using OH at EFS of 11 V/cm was higher than the CH by 86.11%. There is no significant effect between OH at EFS of 11 V/cm and CH in moisture content, refractive index, density, TSS, and viscosity. The optimum level of EFS was 11.5 V/cm, which gave a higher yield (64.93%). OH, save consumed power and cost. The OH gave the highest scores of sensory characteristics compared to CH. Total sugars, monosaccharides, and ketone monosaccharides were detected in the date syrup, and the result was positive, while the quintuple sugars and multiple sugars were negative for all treatments. The OH reduced the cost by 85.78% compared with CH.

Mechanistic and synergistic aspects of ultrasonics and hydrodynamic cavitation for food processing

Compared with traditional methods, cavitation-based processing technology has received extensive attention for its low energy consumption and high processing efficiency. The cavitation phenomenon releases high energy due to the generation and collapse of bubbles, which improves the efficiency of various food processing. This review details the cavitation mechanism of ultrasonic cavitation (UC) and hydrodynamic cavitation (HC), factors affecting cavitation, the application of cavitation technology in food processing, and the application of cavitation technology in the extraction of various natural ingredients. The safety and nutrition of food processed by cavitation technology and future research directions are also discussed. The mechanism of UC refers to longitudinal displacement of the particles of the medium induced by ultrasonic waves causing a series of alternating compression and rarefaction of particles, whereas HC occurs when liquid enters a narrow section and undergoes large pressure differentials, both of which can trigger the generation, growth, and collapse of microbubbles. Cavitation could be applied in microbial inactivation, and drying and freezing processing. In addition, cavitation bubbles can have mechanical and thermal effects on plant cells. In general, cavitation technology is a new sustainable, green, and innovative technology with broad application prospects and capabilities.

Date Fruits as Raw Material for Vinegar and Non-Alcoholic Fermented Beverages

Currently, foods and beverages with healthy and functional properties, especially those that claim to prevent chronic diseases, are receiving more and more interest. As a result, numerous foods and beverages have been launched onto the market. Among the products with enhanced properties, vinegar and fermented beverages have a high potential for growth. Date palm fruits are a versatile raw material rich in sugars, dietary fibers, minerals, vitamins, and phenolic compounds; thus, they are widely used for food production, including date juice, jelly, butter, and fermented beverages, such as wine and vinegar. Furthermore, their composition makes them suitable for the formulation of functional foods and beverages. Microbial transformations of date juice include alcoholic fermentation for producing wine as an end-product, or as a substrate for acetic fermentation. Lactic fermentation is also documented for transforming date juice and syrup. However, in terms of acetic acid bacteria, little evidence is available on the exploitation of date juice by acetic and gluconic fermentation for producing beverages. This review provides an overview of date fruit’s composition, the related health benefits for human health, vinegar and date-based fermented non-alcoholic beverages obtained by acetic acid bacteria fermentation.

Effects of Non-Thermal Treatment on Gilaburu Vinegar (Viburnum opulus L.): Polyphenols, Amino Acid, Antimicrobial, and Anticancer Properties

Simple Summary

In this study, traditionally produced vinegar made from gilaburu (C-GV) and thermally pasteurized gilaburu vinegar (P-GV), and (ultrasound-treated gilaburu vinegar (UT-GV) were evaluated. At the same time, ultrasound treatment enriched 11 phenolic compounds (gallic acid, protocatechuic acid, hydroxybenzoic acid, vanillic acid, p-coumaric acid, rutin, ferulic acid, o-coumaric acid, neohesperidin, quercetin, trans-cinnamic). Ultrasound showed different effects on free amino acids and volatile profiles. In general, ultrasound showed more positive results than thermal pasteurization. Six important minerals (Ca, Fe, K, Mg, Mn, and Zn) were detected in gilaburu vinegar, and ultrasound treatment increased the Fe content. Gilaburu vinegar, prepared by different methods, had potential antibacterial and anti-cancer activity.

Abstract

Gilaburu (Viburnum opulus L.) is an important fruit that has been studied in recent years due to its phytochemicals and health benefits. In this study, traditionally produced vinegar made from gilaburu fruit (C-GV) was evaluated. Vinegar with higher levels of bioactive components optimized by response surface methodology (RSM) was also produced using ultrasound (UT-GV). The maximum optimization result for the bioactive components was achieved at 14 min and 61.2 amplitude. The effectiveness of thermal pasteurization (P-GV) on gilaburu vinegar was evaluated. An increase was detected for every organic acid with ultrasound treatment. In the UT-GV and C-GV samples, arabinose was present, which is useful for stimulating the immune system. Gilaburu vinegar samples contained 29–31 volatile compounds. The smallest amount of volatile compounds was found in P-GV (1280.9 µg/kg), and the largest amounts of volatile compounds were found in C-GV (1566.9 µg/kg) and UT-GV (1244.10 µg/kg). In the UT-GV sample, Fe was increased, but Ca, K, Mg, and Mn were decreased. A total of 15 polyphenols were detected in C-GV, P-GV, and UT-GV samples, and gallic acid was the most common. A total of 17 free amino acids were detected in gilaburu vinegar samples. Ultrasound provided enrichment in total phenolic compounds and total free amino acids. All three vinegar samples had good antimicrobial activity against pathogens. The efficacy of C-GV, P-GV, and UT-GV samples against colon and stomach cancer was determined, but there were no significant differences between them. As a result, ultrasound treatment is notable due to its antimicrobial and anticancer activity, especially for the enrichment of phenolic compounds and amino acids in gilaburu vinegar.

High-Quality Bioethanol and Vinegar Production from Saudi Arabia Dates: Characterization and Evaluation of Their Value and Antioxidant Efficiency

Dates are very rich in various nutritious compounds, especially reducing sugars. Sugars ensure both anaerobic and aerobic fermentation, carried out respectively for the production of bioethanol and vinegar. Currently, the world production of dates is constantly increasing owing to the significant improvement in production conditions following the continuous scientific and technological development of this field. The Kingdom of Saudi Arabia is one of the most important world producers of dates, occupying the second place by producing 17% of the total world production. This is why it has become a national priority to find new ways to exploit and further valorize dates and palm waste in the development of new and sustainable products. The present study was designed to explore the possible study of a variety of date palm by-products in the production of bioethanol and vinegar via Saccharomyces cerevisiae. Different parameters of bioethanol and vinegar production, including pH, time, fermentation temperature, and yeast concentration, were studied and optimized. Chemical, physicochemical, purity behavior, and antioxidant performance were carried out via NMR, FTIR, and antioxidant activity essays (TPC, DPPH, FRAP, and β-carotene bleaching test) with the aim to evaluate the potential of the bioethanol and vinegar samples extracted from date palm by-products. Khalas date vinegar revealed significantly more phenolic content (5.81 mg GAE/mL) (p < 0.05) than the different kinds of vinegar tested (Deglet Nour and Black dates; 2.3 and 1.67 mg GAE/mL, respectively) and the commercial vinegar (1.12 mg GAE/mL). The Khalas date vinegar generally showed a higher carotenoid value and better antioxidant activity than the other vinegars extracted from other date varieties and commercially available vinegar. The results confirmed the high quality of the bioethanol and vinegar products, and the efficiency of the developed production processes.

The Nutritional and Antioxidant Potential of Artisanal and Industrial Apple Vinegars and Their Ability to Inhibit Key Enzymes Related to Type 2 Diabetes In Vitro

The main objective of the current study was to determine the physicochemical properties, antioxidant activities, and α-glucosidase and α-amylase inhibition of apple vinegar produced by artisanal and industrial methods. Apple vinegar samples were analyzed to identify their electrical conductivity, pH, titratable acidity, total dry matter, Brix, density, mineral elements, polyphenols, flavonoids, and vitamin C. The antioxidant activity of apple vinegar samples was evaluated using two tests, total antioxidant capacity (TAC) and DPPH radical scavenging activity. Finally, we determined α-glucosidase and α-amylase inhibitory activities of artisanal and industrial apple vinegar. The results showed the following values: pH (3.69-3.19); electrical conductivity (2.81-2.79 mS/cm); titratable acidity (3.6-5.4); ash (4.61-2.90); °Brix (6.37-5.2); density (1.02476-1.02012), respectively, for artisanal apple vinegar and industrial apple vinegar. Concerning mineral elements, potassium was the most predominant element followed by sodium, magnesium, and calcium. Concerning bioactive compounds (polyphenols, flavonoids, and vitamin C), the apple vinegar produced by the artisanal method was the richest sample in terms of bioactive compounds and had the highest α-glucosidase and α-amylase inhibition. The findings of this study showed that the quality and biological activities of artisanal apple vinegar were more important than industrial apple vinegar.

Potential use of ultrasound to promote fermentation, maturation, and properties of fermented foods: A review

Conventional food fermentation is time-consuming, and maturation of fermented foods normally requires a huge space for long-term storage. Ultrasound is a technology that emerged in the food industry to improve the efficacy of food fermentation and presents great potentials in maturation of fermented foods to produce fermented foods with high quality. Proliferation of microorganisms was observed along with promoted enzyme activities and metabolic performance when treated by a short-term ultrasonication (<30 min) at a relatively low-power (≤100 W). Additionally, ultrasound at a high-power level (≥100 W) was highlighted to promote the maturation of fermented foods through promoting Maillard reaction, oxidation, esterification, and proteolysis. As a result of promoted fermentation and maturation, texture, color, flavor and taste of fermented foods were improved. All the reviewed studies have indicated that ultrasound at the proper conditions would be a promising technique to produce fermented foods with high-quality.

Effect of dielectric barrier discharge plasma, ultra-sonication, and thermal processing on the rheological and functional properties of sugarcane juice

The present work was designed to study the impact of dielectric barrier discharge (DBD) plasma, ultrasound (US), and thermal treatment on the functional, rheological, and microbial analysis of sugarcane juice. The results showed that plasma and US treatment did not significantly affect the pH and color of the juice. Total soluble solids (°Brix) value increased from 16.30 ± 0.10 for untreated to 20.50 ± 0.15 during plasma treatment at 45 V for 2 min and 16.65 ± 0.27 during US treatment (40 kHz, power 240 W, and time 40 min). The maximum increase of 25% in total phenolic contents (TPC) and 21% in total flavonoid contents (TFC) was observed in a plasma-treated sample at 40 and 45 V (for 2 min) respectively, whereas 18% in TPC and 16% TFC was observed in the US-treated sample (40 kHz, power 240 W, and time 30 min) as compared to control sample. Plasma treatment increased the antioxidant activities (Ferric reducing antioxidant power (FRAP) assay and 2,2-Diphenyl-1-picrylhydrazyl (DPPH) activity) toward maximum at 40 V and only 6% of vitamin C was degraded than others. Similarly, plasma treatment significantly reduced particle size, which further led to decreased significantly (P < 0.05) the apparent viscosity of sugarcane juice with a rise in shear rate and drove to a speedy breakdown on initial shearing. A significant reduction was observed in the microbial load among all treatments as compared to the control. Significant reductions of 3.6 and 0.50 log CFU/mL were observed in the total aerobic mesophilic and yeast and mold counts after DBD plasma treatment at 45 V for 2 min, respectively. Thus, we can conclude that novel technology like plasma treatment can be effectively used at an industrial scale for the preservation and processing of sugarcane juice. PRACTICAL APPLICATION: Nowadays, novel processing techniques are employed to improve the nutritional quality and stability of juices. The consequences of the present research showed that DBD plasma treatment could improve the TPC, TFC, antioxidant activities, vitamin C, and rheological properties while reducing the activity of the microbial load better than the US and thermal treatment. The verdicts described that novel processing methods can enhance the quality of sugarcane juice at an industrial scale.

Impact of pulsed electric field treatments on the growth parameters of wheat seeds and nutritional properties of their wheat plantlets juice

This study was designed to explore the impacts of the pulsed electric field (PEF; 2 to 6 kV/cm; a number of pulses 25 and 50) on wheat (Tritium aestivum L.) seeds before imbibition to improve the germination, growth, and their nutritional profile in juice form. It was observed that the PEF treatment at 6 kV/cm at 50 pulses increased water uptake, germination of seeds, and growth parameters of seedlings. A significant increase in total phenolic contents, DPPH, chlorophylls, carotenoids, soluble proteins, minerals, and amino acids in PEF-treated seeds plantlets juice as compared to the untreated seeds plantlets juice was observed. The results indicate that the PEF may effectively stimulate the growth of the wheat kernels and positively affect their metabolism, optimize the nutrients, and enhance the strength of the wheat kernels plantlets.

Novel processing techniques and spinach juice: Quality and safety improvements

In this study, the combined effect of ultrasound (US) and pulsed electric field (PEF) techniques was analyzed for the quality improvement and microbial safety of spinach juice. The spinach juice was treated with US at frequency of 40 kHz, radiating power of 200 W below 30 ± 2 °C temperature for 21 min in ultrasonic bath cleaner, and PEF treatment (pulse frequency: 1 kHz, flow rate: 60 mL/min, temperature: 30 ± 2 °C, time: 335 µs, electric field strength 9 kV/cm) was done. In results, the combined (US-PEF) treatment attained the highest value of minerals and total free amino acids as compared to US or PEF treatment alone. US-PEF treatment significantly reduced the total plate count (3.83 to 1.97 log CFU/mL), E. coli/Coliform (1.90 to 0.75 log CFU/mL) and yeast and mold (4.23 to 2.22 log CFU/mL). Fourier-transform infrared spectroscopy (FT-IR) spectra showed that all nonthermal treatments led to a higher concentration of carbonyl compounds rather generate new carbonyl compounds. US-PEF treatment significantly reduced the particle size. The rheology of spinach juice was drastically changed by all nonthermal techniques, indicating non-Newtonian modal accompanied by a decrease of consistency index (K), apparent viscosity (η), and increase of flow behavior (n). Overall, the improved quality of spinach juice shows the suitability of both technologies for industrial applications despite the variations in rheological properties. PRACTICAL APPLICATION: Nowadays, nonthermal technologies like US and PEF are being used to enhance the nutritional quality and stability of different fruits and vegetable juices. The current research shows that US-PEF application can enhance the free amino acids and mineral contents while significantly decrease microbial activities and particle size. The rheology of spinach juice can be dramatically changed, through the reduction of consistency index (K), apparent viscosity (η) and elevation of flow behavior (n). The results of this research proposed that US-PEF treatment can be a more suitable nonthermal application to enhance the quality of spinach juice at an industrial scale.

Effect of Pulsed Electric Field Pretreatment of Date Palm Fruits on Free Amino Acids, Bioactive Components, and Physicochemical Characteristics of the Alcoholic Beverage

This research is aimed to observe the impact of pulsed electric field (PEF) application on the free amino acids, physicochemical characteristics, and bioactive components of alcoholic beverages processed from date palm fruits. The fruits were treated by PEF (frequency: 10 Hz, treatment time: 100 µs, pulses number: 40 µs for electric field: 1.38, 2.02, and 2.92 kV/cm, respectively). A significant increase (P < 0.05) in the total free amino acids and phenolic and flavonoid contents (2.92 > 2.02 > 1.38 kV/cm) was observed. There was a minor significant difference among the treated samples in the total soluble solid, alcohol, and total sugar contents, while there were no significant changes in the other parameters, including the color attributes. PRACTICAL APPLICATION: This study observed whether PEF treatment has a positive impact on the processing of alcoholic beverages of date palm fruits. PEF was found to improve the bioactive components and nutritional value of alcoholic beverages processed from date palm fruits. This finding suggests that PEF can be a better technique to enhance the quality characteristics of date palm fruit alcoholic beverages.

Pulsed Electric Field-Assisted Ethanolic Extraction of Date Palm Fruits: Bioactive Compounds, Antioxidant Activity and Physicochemical Properties

The current study was aimed to observe the influence of pulsed electric field (PEF) on the extraction of bioactive components; antioxidant activity and physicochemical properties of date palm fruit extract (DPFE) as compared to the extract untreated by PEF. The fruit was treated with PEF (frequency: 10 Hz, time: 100 µs, pulses number: 30, electric field strength (EFS): 1, 2, and 3 kV/cm. The results show that PEF has a positive impact on the total content of carotenoids, anthocyanins, flavonoids, and phenolics by increasing the EFS. DPFE treated with PEF exhibit a strong antioxidant activity as compared to untreated extract, while electrical conductivity, pH values, and titratable acidity were not affected by PEF. The results indicate a notable increase in the volatile components in DPFE treated with PEF at 3 kV/cm. Thus, PEF treatment can assist the ethanolic extraction of DPFE to improve the bioactivity and antioxidative activity. These findings suggest that PEF can be a more suitable technique to enhance solvent extraction on a commercial basis.

Thermo-Ultrasound-Based Sterilization Approach for the Quality Improvement of Wheat Plantlets Juice

The impact of thermo–ultrasound (TU) on the quality of fresh wheat plantlets juice is described in this study. Fresh wheat plantlets juice was treated with TU using ultrasound (US) bath cleaner with different treatment variables, including power (70%, 420 W), frequency (40 kHz), processing time (20 and 40 min) and temperature (30, 45 and 60 °C) for the determination of free amino acids, minerals, microbial loads and bioactive compounds. The treatments have non-significant effects in ºBrix, pH, and titratable acidity while a significant increase in non-enzymatic browning, viscosity, and cloud value. The TU treatment at 30 °C for 20 and 40 min has achieved the highest value of total phenolics, flavonoids, total antioxidant capacity, 2, 2-diphenyl-1-picrylhydrazyl (DPPH), carotenoids, anthocyanin contents, chlorophyll (a + b), minerals and free amino acids than other treatments as well as untreated sample. A lightly visible variation in the color was observed among all treatments. TU treatments also showed a significant impact on the reduction of microbial loads at 60 °C for 40 min. The verdicts revealed that TU at low temperature a viable option to improve the quality of wheat plantlets juice at an industrial scale as compared to alone.