INTRODUCTION: This study focused on the formulation processing and antimicrobial activities of Or... more INTRODUCTION: This study focused on the formulation processing and antimicrobial activities of Origanum and Thyme essential oils (OEO) (TEO) and their nanoemulsions (OEON) (TEON) on gram-positive and gram-negative bacteria and yeast. Optimal nanoemulsion formulation and stability were achieved through balancing between requisite hydrophilic-lipophilic balance (rHLB) and surfactant concentration (Smix) of nanoemulsions. METHOD: The smallest droplet sizes of OEON: (z -185.1 nm ± 0.85) and TEON (z -130.1 nm ± 0.60), were achieved by using 10 g/100 mL of OEO and TEO with 15 g/100 mL Smix at ultrasonication for 2 min with no phase separation. The size of nanoemulsion droplet and PDI was found to be influenced by HLB value, treatment time, and Smix concentration. Antimicrobial analyses, including a zone of inhibition, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill kinetics assay, were performed against Escherichia coli, Staphylococcus aureu...
Energy drinks (EDs) are a type of sweetened and non-alcoholic beverage with high content of caffe... more Energy drinks (EDs) are a type of sweetened and non-alcoholic beverage with high content of caffeine. EDs were prepared from date juice enriched with different concentrations of ginger rhizomes extract, moringa leaf extract, and caffeine. Physicochemical properties (pH, TSS, and color parameters), total phenolic content (TPC), antioxidant activity, microbiological quality, and sensory characteristics were evaluated for freshly prepared EDs and during storage. The results showed that freshly prepared EDs from date juice and natural extracts revealed lower pH, higher TSS, and lower color parameters than the control. The inclusion of date juice and natural extracts improved the TPC, antioxidant activity, and microbiological quality of freshly prepared EDs. Storage studies exhibited that EDs containing date juice and natural extracts were more stable during storage in terms of all quality parameters estimated. However, the ED made from date juice, ginger extract, moringa extract, and ca...
The use of natural ingredients to preserve the quality of fresh fruits is a promising approach to... more The use of natural ingredients to preserve the quality of fresh fruits is a promising approach to healthier products and a more sustainable industry. The present study was carried out to assess the effect of lactic acid (LA) and guava leaf extract (GLE) as natural preservatives on the quality parameters of Khalal Barhi dates. Physicochemical properties, antioxidant activity, color parameters, firmness, sensory properties, and yeast and mold counts of date fruits were evaluated during five weeks of storage at 4 ± 1 °C. The bioactive compounds in GLE were estimated by HPLC, which exhibited that GLE contains significant amounts of bioactive compounds, mainly, phenolics and flavonoids. With prolonged storage, the moisture content decreased, while the total soluble solids (TSS) increased in all samples. Similarly, a slight decrease in the pH with a concomitant increase in titratable acidity (TA) was observed throughout the storage. Generally, the samples treated with natural preservative...
Byproducts of second-grade dates and sweet potato tubers of noncommercial standard are produced a... more Byproducts of second-grade dates and sweet potato tubers of noncommercial standard are produced along with the main product and are just as important as the main product but cannot be sold in the open market, as they may not be considered acceptable by consumers. Such byproducts can be valorized through the manufacture of a wide range of functional food products with high market appeal, such as jams. The research approach of this study included measuring antioxidant activity, total flavonoids, polyphenols, physicochemical and color indices, pH, and total sugar, as well as conducting a sensory evaluation, of mixed jams composed of different ratios of date jam (DFJ) to sweet potato jam (SPJ), namely, DP1 (80:20), DP2 (70:30), DP3 (60:40), and DP4 (50:50). To date, no other studies have considered producing mixed jam from dates and sweet potato byproducts. The sensory evaluation results indicated that jam DP4 (consisting of 50% date and 50% sweet potato) had the maximum overall accepta...
The use of natural preservatives in the storage of fresh fruits is a promising approach to health... more The use of natural preservatives in the storage of fresh fruits is a promising approach to healthier and more sustainable food processing. The current study was conducted to evaluate the effect of pomegranate peel extract (PPE) and lactic acid (LA) as natural preservatives on the shelf life of Khalal Barhi date fruits. Physicochemical properties, antioxidant activity, color parameters, texture profile, sensory characteristics, and microbiological quality of date fruits were evaluated during six weeks of cold storage (4 ± 1 °C). The bioactive compounds in PPE were determined by HPLC analysis, which showed that PPE is a rich source of bioactive compounds, particularly phenolics and flavonoids. The results exhibited decreased moisture content (from 68.36–68.43 to 62.13–63.11%) and an increased soluble solids content (from 27.16–27.24 to 31.45–33.91%) in all samples with prolonged storage. Likewise, a slight decrease in the pH (from 6.00–6.28 to 4.89–5.29) with an increase in acidity (f...
Novel biosensors based on carboxymethyl cellulose extract from date palm fronds containing Ag nan... more Novel biosensors based on carboxymethyl cellulose extract from date palm fronds containing Ag nanoparticles as an electrochemical working electrode for fast hydroxymethylfurfural (HMF) sensing in date molasses were prepared. The morphological, structural, and crystallinity characteristics of the prepared Ag@CMC were described via SEM, DLS, TEM, and XRD. In addition, Raman spectroscopy and UV–VIS spectroscopy were performed, and thermal stability was studied. The investigated techniques indicated the successful incorporation of AgNPs into the CMC polymer. The sensing behavior of the prepared AgNPs@CMC electrode was studied in terms of cyclic voltammetry and linear scan voltammetry at different HMF concentrations. The results indicated high performance of the designed AgNPs@CMC, which was confirmed by the linear behavior of the relationship between the cathodic current and HMF content. Besides, real commercial samples were investigated using the novel AgNPs@CMC electrode.
Date press cake (DPC) is a by-product of the date syrup industry with a high content of dietary f... more Date press cake (DPC) is a by-product of the date syrup industry with a high content of dietary fibers, minerals, and antioxidant compounds. Accordingly, the present study aimed to evaluate the inclusion of DPC on the color parameters, texture profile, sensory evaluation, microstructure properties, total phenolics, and antioxidant capacity of date jam. The DPC was included in the preparation of date jam in an increasing level of 0, 3, 6, 9, and 12% (w/w). The results revealed that increasing DPC levels significantly increased the hardness, cohesiveness, adhesiveness, and chewiness properties of date jam. The increase in DPC inclusion levels significantly decreased the L* values and increased the a*, b*, and ΔE values of the jam. The DPC addition significantly increased the phenolics content and antioxidant capacity in a dose-dependent manner and the highest value reported in the jam contained 12% DPC by 40.02 and 11.50% compared to the control, respectively. The scanning electron mi...
Overproduction of date fruits with limited industrial utilization leads to huge waste and losses,... more Overproduction of date fruits with limited industrial utilization leads to huge waste and losses, especially in bisr (the first stage of date maturity). Therefore, this study aimed to investigate the potential of using bisr date powder (BDP), which is rich in dietary fiber, flavonoids, and phenolic and antioxidant compounds, as a replacement for breadcrumbs in the beef burgers. The beef burger samples were produced by replacing breadcrumb powder with different concentration levels of BDP (0.0, 25, 50, 75, and 100%). All the samples were evaluated for their quality characteristics, including chemical composition, cooking properties, texture profile, organoleptic characteristics, and microbial profile. The results revealed that the gradual replacement of breadcrumbs with BDP in beef burgers significantly decreased moisture, protein, and lipid contents and significantly increased ash and carbohydrate contents compared to the control. The substitution of breadcrumbs with BDP at 50, 75, ...
Tomato pastes (TP) enriched with rice flour (RF) were evaluated for physico-chemical properties, ... more Tomato pastes (TP) enriched with rice flour (RF) were evaluated for physico-chemical properties, rheological characteristics, and storage stability. TP was prepared from fresh tomato fruits with the addition of RF at the levels of 2, 4, and 6% (w/w) using the cold break method and stored for 12 weeks at ambient temperature. Insignificant changes in the chemical compositions of TP samples were observed. Pastes contained RF revealed higher L* values than control. During storage, L* and a* values of TP decreased, while b* values increased. The a*/b* ratio of TP contained RF were approximately stable during storage and were at acceptable levels. Samples contained RF showed higher pH and total soluble solids (TSS) with lower ascorbic acid content (AAC), acidity, and Bostwick than control. The AAC and pH decreased, whereas acidity, TSS, and Bostwick increased during storage. The paste containing 4% RF showed the highest sensory scores among all tested samples at zero time and during stora...
The extraction of date syrup produces a large quantity of by-product known as date press cake (DP... more The extraction of date syrup produces a large quantity of by-product known as date press cake (DPC). This study aimed to utilize valuable ingredients of the DPC by adding 0 (Control), 2, 4, and 6% (g/100 g) of its powder to drinkable yogurt before fermentation. The physicochemical properties, texture profile, and sensory evaluation of the treated DPC-based drinkable yogurt (DPC drinkable yogurt) were measured after fermentation and 5, 10, and 15 days of storage at 4 °C. The modeling of the most critical quality attributes, i.e., pH, acidity, syneresis, water holding capacity (WHC), viscosity, and color difference (ΔE), was conducted to predict their values based on the DPC percentage and storage period. The DPC drinkable yogurt’s total solids, protein, and fat ranged between 11.19–11.83, 3.10–3.42, and 2.26–2.34%, respectively. Adding 2–6% DPC slightly increased the pH of DPC drinkable yogurt and decreased its acidity (p > 0.05) during storage. Increasing the DPC percent in DPC d...
The present study aimed to utilize texturizing inulin as a functional food ingredient that affect... more The present study aimed to utilize texturizing inulin as a functional food ingredient that affects the maintaining of good health and fat replacement for improving texture of Egyptian Karish cheese and compensating the fatness. Effect of addition of texturizing inulin (Frutafit TEX) at levels 2 and 4 % (w ⁄w) on physicochemical properties, yield, textural, microstructure, microbiological counts and sensory characteristics were investigated. The results revealed that the addition of texturizing inulin increased yield values and moisture content of Karish cheeses compared with control. Protein and ash content were not influenced significantly as compared to the control of storage at 4 0C as a result of texturized inulin addition. Differences in the microstructure of Karish cheese with inulin and control reflected the differences in its inulin content. Hardness decreased from 495 (g) in control to 216 and 143 in Karish cheese made with 2 and 4 % texturized inulin at zero time of storag...
The present study aimed to utilize texturizing inulin as a functional food ingredient that affect... more The present study aimed to utilize texturizing inulin as a functional food ingredient that affects the maintaining of good health and fat replacement for improving texture of Egyptian Karish cheese and compensating the fatness. Effect of addition of texturizing inulin (Frutafit TEX) at levels 2 and 4% (w ⁄w) on physicochemical properties, yield, textural, microstructure, microbiological counts and sensory characteristics were investigated. The results revealed that the addition of texturizing inulin increased yield values and moisture content of Karish cheeses compared with control. Protein and ash content were not influenced significantly as compared to the control of storage at 4 0 C as a result of texturized inulin addition. Differences in the microstructure of Karish cheese with inulin and control reflected the differences in its inulin content. Hardness decreased from 495 (g) in control to 216 and 143 in Karish cheese made with 2 and 4 % texturized inulin at zero time of storag...
For utilization of lactose in salted and unsalted cheese whey, intergeneric protoplast fusion bet... more For utilization of lactose in salted and unsalted cheese whey, intergeneric protoplast fusion between lactose nonfermenting, salt-tolerant Saccharomyces cerevisiae ATCC4126 and lactose fermenting Kluyveromyces lactis CBS683 was carried out. The fusion process gave rise to new hybrid yeast strains that revealed higher significant DNA contents than parental strains. The recombinants showed growth on either lactose or sucrose. The ethanol yields by some recombinants were 5.55% from sweet whey and 4.66% from salted whey containing up to 6% sodium chloride compared to 4.15 and 2.86% for parental K. lactis CBS683, respectively.
INTRODUCTION: This study focused on the formulation processing and antimicrobial activities of Or... more INTRODUCTION: This study focused on the formulation processing and antimicrobial activities of Origanum and Thyme essential oils (OEO) (TEO) and their nanoemulsions (OEON) (TEON) on gram-positive and gram-negative bacteria and yeast. Optimal nanoemulsion formulation and stability were achieved through balancing between requisite hydrophilic-lipophilic balance (rHLB) and surfactant concentration (Smix) of nanoemulsions. METHOD: The smallest droplet sizes of OEON: (z -185.1 nm ± 0.85) and TEON (z -130.1 nm ± 0.60), were achieved by using 10 g/100 mL of OEO and TEO with 15 g/100 mL Smix at ultrasonication for 2 min with no phase separation. The size of nanoemulsion droplet and PDI was found to be influenced by HLB value, treatment time, and Smix concentration. Antimicrobial analyses, including a zone of inhibition, minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and time-kill kinetics assay, were performed against Escherichia coli, Staphylococcus aureu...
Energy drinks (EDs) are a type of sweetened and non-alcoholic beverage with high content of caffe... more Energy drinks (EDs) are a type of sweetened and non-alcoholic beverage with high content of caffeine. EDs were prepared from date juice enriched with different concentrations of ginger rhizomes extract, moringa leaf extract, and caffeine. Physicochemical properties (pH, TSS, and color parameters), total phenolic content (TPC), antioxidant activity, microbiological quality, and sensory characteristics were evaluated for freshly prepared EDs and during storage. The results showed that freshly prepared EDs from date juice and natural extracts revealed lower pH, higher TSS, and lower color parameters than the control. The inclusion of date juice and natural extracts improved the TPC, antioxidant activity, and microbiological quality of freshly prepared EDs. Storage studies exhibited that EDs containing date juice and natural extracts were more stable during storage in terms of all quality parameters estimated. However, the ED made from date juice, ginger extract, moringa extract, and ca...
The use of natural ingredients to preserve the quality of fresh fruits is a promising approach to... more The use of natural ingredients to preserve the quality of fresh fruits is a promising approach to healthier products and a more sustainable industry. The present study was carried out to assess the effect of lactic acid (LA) and guava leaf extract (GLE) as natural preservatives on the quality parameters of Khalal Barhi dates. Physicochemical properties, antioxidant activity, color parameters, firmness, sensory properties, and yeast and mold counts of date fruits were evaluated during five weeks of storage at 4 ± 1 °C. The bioactive compounds in GLE were estimated by HPLC, which exhibited that GLE contains significant amounts of bioactive compounds, mainly, phenolics and flavonoids. With prolonged storage, the moisture content decreased, while the total soluble solids (TSS) increased in all samples. Similarly, a slight decrease in the pH with a concomitant increase in titratable acidity (TA) was observed throughout the storage. Generally, the samples treated with natural preservative...
Byproducts of second-grade dates and sweet potato tubers of noncommercial standard are produced a... more Byproducts of second-grade dates and sweet potato tubers of noncommercial standard are produced along with the main product and are just as important as the main product but cannot be sold in the open market, as they may not be considered acceptable by consumers. Such byproducts can be valorized through the manufacture of a wide range of functional food products with high market appeal, such as jams. The research approach of this study included measuring antioxidant activity, total flavonoids, polyphenols, physicochemical and color indices, pH, and total sugar, as well as conducting a sensory evaluation, of mixed jams composed of different ratios of date jam (DFJ) to sweet potato jam (SPJ), namely, DP1 (80:20), DP2 (70:30), DP3 (60:40), and DP4 (50:50). To date, no other studies have considered producing mixed jam from dates and sweet potato byproducts. The sensory evaluation results indicated that jam DP4 (consisting of 50% date and 50% sweet potato) had the maximum overall accepta...
The use of natural preservatives in the storage of fresh fruits is a promising approach to health... more The use of natural preservatives in the storage of fresh fruits is a promising approach to healthier and more sustainable food processing. The current study was conducted to evaluate the effect of pomegranate peel extract (PPE) and lactic acid (LA) as natural preservatives on the shelf life of Khalal Barhi date fruits. Physicochemical properties, antioxidant activity, color parameters, texture profile, sensory characteristics, and microbiological quality of date fruits were evaluated during six weeks of cold storage (4 ± 1 °C). The bioactive compounds in PPE were determined by HPLC analysis, which showed that PPE is a rich source of bioactive compounds, particularly phenolics and flavonoids. The results exhibited decreased moisture content (from 68.36–68.43 to 62.13–63.11%) and an increased soluble solids content (from 27.16–27.24 to 31.45–33.91%) in all samples with prolonged storage. Likewise, a slight decrease in the pH (from 6.00–6.28 to 4.89–5.29) with an increase in acidity (f...
Novel biosensors based on carboxymethyl cellulose extract from date palm fronds containing Ag nan... more Novel biosensors based on carboxymethyl cellulose extract from date palm fronds containing Ag nanoparticles as an electrochemical working electrode for fast hydroxymethylfurfural (HMF) sensing in date molasses were prepared. The morphological, structural, and crystallinity characteristics of the prepared Ag@CMC were described via SEM, DLS, TEM, and XRD. In addition, Raman spectroscopy and UV–VIS spectroscopy were performed, and thermal stability was studied. The investigated techniques indicated the successful incorporation of AgNPs into the CMC polymer. The sensing behavior of the prepared AgNPs@CMC electrode was studied in terms of cyclic voltammetry and linear scan voltammetry at different HMF concentrations. The results indicated high performance of the designed AgNPs@CMC, which was confirmed by the linear behavior of the relationship between the cathodic current and HMF content. Besides, real commercial samples were investigated using the novel AgNPs@CMC electrode.
Date press cake (DPC) is a by-product of the date syrup industry with a high content of dietary f... more Date press cake (DPC) is a by-product of the date syrup industry with a high content of dietary fibers, minerals, and antioxidant compounds. Accordingly, the present study aimed to evaluate the inclusion of DPC on the color parameters, texture profile, sensory evaluation, microstructure properties, total phenolics, and antioxidant capacity of date jam. The DPC was included in the preparation of date jam in an increasing level of 0, 3, 6, 9, and 12% (w/w). The results revealed that increasing DPC levels significantly increased the hardness, cohesiveness, adhesiveness, and chewiness properties of date jam. The increase in DPC inclusion levels significantly decreased the L* values and increased the a*, b*, and ΔE values of the jam. The DPC addition significantly increased the phenolics content and antioxidant capacity in a dose-dependent manner and the highest value reported in the jam contained 12% DPC by 40.02 and 11.50% compared to the control, respectively. The scanning electron mi...
Overproduction of date fruits with limited industrial utilization leads to huge waste and losses,... more Overproduction of date fruits with limited industrial utilization leads to huge waste and losses, especially in bisr (the first stage of date maturity). Therefore, this study aimed to investigate the potential of using bisr date powder (BDP), which is rich in dietary fiber, flavonoids, and phenolic and antioxidant compounds, as a replacement for breadcrumbs in the beef burgers. The beef burger samples were produced by replacing breadcrumb powder with different concentration levels of BDP (0.0, 25, 50, 75, and 100%). All the samples were evaluated for their quality characteristics, including chemical composition, cooking properties, texture profile, organoleptic characteristics, and microbial profile. The results revealed that the gradual replacement of breadcrumbs with BDP in beef burgers significantly decreased moisture, protein, and lipid contents and significantly increased ash and carbohydrate contents compared to the control. The substitution of breadcrumbs with BDP at 50, 75, ...
Tomato pastes (TP) enriched with rice flour (RF) were evaluated for physico-chemical properties, ... more Tomato pastes (TP) enriched with rice flour (RF) were evaluated for physico-chemical properties, rheological characteristics, and storage stability. TP was prepared from fresh tomato fruits with the addition of RF at the levels of 2, 4, and 6% (w/w) using the cold break method and stored for 12 weeks at ambient temperature. Insignificant changes in the chemical compositions of TP samples were observed. Pastes contained RF revealed higher L* values than control. During storage, L* and a* values of TP decreased, while b* values increased. The a*/b* ratio of TP contained RF were approximately stable during storage and were at acceptable levels. Samples contained RF showed higher pH and total soluble solids (TSS) with lower ascorbic acid content (AAC), acidity, and Bostwick than control. The AAC and pH decreased, whereas acidity, TSS, and Bostwick increased during storage. The paste containing 4% RF showed the highest sensory scores among all tested samples at zero time and during stora...
The extraction of date syrup produces a large quantity of by-product known as date press cake (DP... more The extraction of date syrup produces a large quantity of by-product known as date press cake (DPC). This study aimed to utilize valuable ingredients of the DPC by adding 0 (Control), 2, 4, and 6% (g/100 g) of its powder to drinkable yogurt before fermentation. The physicochemical properties, texture profile, and sensory evaluation of the treated DPC-based drinkable yogurt (DPC drinkable yogurt) were measured after fermentation and 5, 10, and 15 days of storage at 4 °C. The modeling of the most critical quality attributes, i.e., pH, acidity, syneresis, water holding capacity (WHC), viscosity, and color difference (ΔE), was conducted to predict their values based on the DPC percentage and storage period. The DPC drinkable yogurt’s total solids, protein, and fat ranged between 11.19–11.83, 3.10–3.42, and 2.26–2.34%, respectively. Adding 2–6% DPC slightly increased the pH of DPC drinkable yogurt and decreased its acidity (p > 0.05) during storage. Increasing the DPC percent in DPC d...
The present study aimed to utilize texturizing inulin as a functional food ingredient that affect... more The present study aimed to utilize texturizing inulin as a functional food ingredient that affects the maintaining of good health and fat replacement for improving texture of Egyptian Karish cheese and compensating the fatness. Effect of addition of texturizing inulin (Frutafit TEX) at levels 2 and 4 % (w ⁄w) on physicochemical properties, yield, textural, microstructure, microbiological counts and sensory characteristics were investigated. The results revealed that the addition of texturizing inulin increased yield values and moisture content of Karish cheeses compared with control. Protein and ash content were not influenced significantly as compared to the control of storage at 4 0C as a result of texturized inulin addition. Differences in the microstructure of Karish cheese with inulin and control reflected the differences in its inulin content. Hardness decreased from 495 (g) in control to 216 and 143 in Karish cheese made with 2 and 4 % texturized inulin at zero time of storag...
The present study aimed to utilize texturizing inulin as a functional food ingredient that affect... more The present study aimed to utilize texturizing inulin as a functional food ingredient that affects the maintaining of good health and fat replacement for improving texture of Egyptian Karish cheese and compensating the fatness. Effect of addition of texturizing inulin (Frutafit TEX) at levels 2 and 4% (w ⁄w) on physicochemical properties, yield, textural, microstructure, microbiological counts and sensory characteristics were investigated. The results revealed that the addition of texturizing inulin increased yield values and moisture content of Karish cheeses compared with control. Protein and ash content were not influenced significantly as compared to the control of storage at 4 0 C as a result of texturized inulin addition. Differences in the microstructure of Karish cheese with inulin and control reflected the differences in its inulin content. Hardness decreased from 495 (g) in control to 216 and 143 in Karish cheese made with 2 and 4 % texturized inulin at zero time of storag...
For utilization of lactose in salted and unsalted cheese whey, intergeneric protoplast fusion bet... more For utilization of lactose in salted and unsalted cheese whey, intergeneric protoplast fusion between lactose nonfermenting, salt-tolerant Saccharomyces cerevisiae ATCC4126 and lactose fermenting Kluyveromyces lactis CBS683 was carried out. The fusion process gave rise to new hybrid yeast strains that revealed higher significant DNA contents than parental strains. The recombinants showed growth on either lactose or sucrose. The ethanol yields by some recombinants were 5.55% from sweet whey and 4.66% from salted whey containing up to 6% sodium chloride compared to 4.15 and 2.86% for parental K. lactis CBS683, respectively.
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