Bhawna Sobti’s research while affiliated with United Arab Emirates University and other places

Date fruits (DFs) are lucrative fruits with both nutritional and medicinal benefits. Although DF byproducts have gained interest as potential functional food ingredients, the functional role of DF waxes remains unexplored. Most plant fruits, including DFs,had a lipophilic cuticular layer; and constitutes of epicuticular wax (EPW), which has an important role in respiration losses, mechanical support, fruit softening, and pathogen resistance. In this study, the compositional and antioxidant properties of EPW from Majdool, Khalas, and Fard DFs were investigated. Moreover, thermal transitions of EPW were examined. Results revealed the highest EPW yield in Majdool (16.62 ± 1.68 mg wax/cm²) and the lowest in Khalas (0.075 ± 0.008 mg wax/cm²). Ultraviolet–visible spectroscopy showed maximum absorptivity at 250 and 290 nm across all varieties, corresponding to conjugated dienes and trienes, respectively. Fourier transform infrared peaks confirmed the presence of hydroxyl, methylene, and carbonyl groups, including specific domains of phenolic compounds. Khalas and Fard EPWs reported more total phenolic content and scavenging activity than Majdool EPW. The variations were observed in the melting temperatures of EPW, ranging from 60 °C to 85 °C. These findings establish a theoretical foundation for the potential application of DF EPW in food and pharmaceutical industries.

Background: Camel milk (CM) and its fermentation products have acclaimed nutritional and health benefits, although they are often associated with low marketability because of a unique flavor, which is unpleasant to certain consumers. Incorporating fruit purees is an attractive method of adding a pleasant taste and masking the undesirable flavor in such dairy products. Methods: We investigated the effects of supplementing plain fermented CM laban with pectin (0.2%) and a fruit puree (apricot, blueberry, mango, peach, pineapple, or strawberry) of varying concentrations (0%, 5%, 15%, and 25%) on the products' physicochemical, rheological, antioxidant, and sensory properties. The labans were analyzed for dry matter content, color (L*, a*, b*), pH, titratable acidity, and rheology. Total phenolic content and antioxidant property were determined using Folin–Ciocalteu and ABTS methods and sensory profile was studied using quantitative descriptive analysis. Results and discussion: The labans fortified with 15% and 25% purees had higher dry matter content than the control samples. Addition of fruit purees darkened the color of the laban samples and lowered the L* value but did not affect their titratable acidity, except for the apricot puree. Labans containing blueberry, pineapple, and strawberry purees had higher whey-off than those containing peach, apricot, mango, or the control samples. The storage and loss moduli, and viscosity values of laban samples supplemented with peach or pineapple puree (at 15% and 25%, and at 25%, respectively) were increased compared to the other samples. The power law model sufficiently explained the flow of all labans, indicating a shear-thinning behavior. The addition of purees increased the total phenolic content and antioxidant activities of all labans, while peach puree in particular, improved the sensory quality of the CM laban, owing to its high fiber and protein content and low total soluble solids. Conclusion: A 25% peach puree significantly improved all sensory properties of CM labans.

Double emulsions (W1/O/W2) have long been used in the food and pharmaceutical industries to encapsulate hydrophobic and hydrophilic drugs and bioactive compounds. This study investigated the effect of different types of emulsifiers (plant- vs. animal-based proteins) on the encapsulation properties of Mentha piperita leaf extract (MLE) prepared using the double emulsion method. Using response surface methodology, the effect of ultrasound-assisted extraction conditions (amplitude 20–50%; time 10–30 min; ethanol concentration 70–90%) on the total phenolic content (TPC) and antioxidant activity (percent inhibition) of the MLE was studied. MLE under optimized conditions (ethanol concentration 76%; amplitude 39%; time 30 min) had a TPC of 62.83 mg GA equivalents/g and an antioxidant activity of 23.49%. The optimized MLE was encapsulated using soy, pea, and whey protein isolates in two emulsifying conditions: 4065× g/min and 4065× g/30 s. The droplet size, optical images, rheology, and encapsulation efficiency (EE%) of the different encapsulated MLEs were compared. The W1/O/W2 produced at 4065× g/min exhibited a smaller droplet size and higher EE% and viscosity than that prepared at 4065× g/30 s. The higher EE% of soy and pea protein isolates indicated their potential as an effective alternative for bioactive compound encapsulation.

Nanoemulsions are optically transparent and offer good stability, bioavailability, and control over the targeted delivery and release of lipophilic active components. In this study, pea protein isolate (PPI)-stabilized O/W nanoemulsions were evaluated using response surface methodology to obtain optimized ultra-nanoemulsions of Sauter mean diameter (D3,2) < 100 nm using a high-pressure homogenizer (HPH). Furthermore, the effect of food matrix electrolytes, i.e., the pH and ionic strength, on the emulsion (prepared at optimized conditions) was investigated. The results revealed that the droplet size distribution of emulsions was mainly influenced by the PPI concentration and the interaction of oil concentration and HPH pressure. Moreover, a non-significant increase in droplet size was observed when the nanoemulsions (having an initial D3,2 < 100 nm) were stored at 4 °C for 7 days. Based on the current experimental design, nanoemulsions with a droplet size < 100 nm can effectively be prepared with a high PPI concentration (6.35%), with less oil (1.95%), and at high HPH pressure (46.82 MPa). Such emulsions were capable of maintaining a droplet size below 100 nm even at ionic conditions of up to 400 mM NaCl and at acidic pH.

In fruit processing industry, edible coatings/films are usually applied on various fruits to provide protection against microorganisms and to regulate various biological functions of the fruit. The current research in this domain is more focused on exploring naturally occurring bioactive materials to develop active edible coatings that can offer an extended functionality than just providing barrier properties. Therefore, here we report the application of aloe vera gel-based edible coatings, either as standalone or in combination with lemongrass essential oil to enhance the shelf life of the soft date fruit variety (as soft dates are usually more prone to spoilage). The pure aloe vera gel coatings were aqueous mixtures of 25% aloe vera gel; whereas, nanoemulsion-based coatings of lemongrass essential oil (1-5%) and aloe vera gel (25% aqueous mixture) were prepared through a high-pressure homogenizer. After preliminary physicochemical characterization of the prepared coating mixtures, the date fruit samples were dipped in coating mixtures, dried, and then stored at room temperature for 4 weeks. The analyses of date fruits during the storage revealed that the applied coatings did help in retention of physicochemical attributes (e.g., moisture, texture, and pH) and also significantly prevented microbial growth. More specifically, the nanoemulsions based coatings of lemongrass essential oil (up to 3%) and aloe vera gel exhibited excellent antifungal properties, which is quite remarkable as the date fruits are usually more susceptible to fungal growth than the bacterial growth. Based on these findings, the date fruit processing industry can utilize these natural antimicrobial coatings for the shelf life extension of date fruits.

The study aimed to produce natural additive-free powder from date fruits (Phoenix dactylifera L.). Dehydration of two date fruit varieties, i.e., Sukkari (semi-dry) and Barakawi (dry) was perforned at 65, 70 and 75 °C up to 72 h using a cabinet dryer. A temperature of 70 °C was found optimum for drying of both varieties by considering drying rate, total phenolic content, and hydroxymethylfurfural content. Barakawi date powder was found better than the Sukkari counterpart on comparing the water activity and clumping, mainly due to a low initial moisture content of the corresponding date fruit. To overcome the issue of clumping, the powders were compressed into tablets and cubes. The solubilities of the tablets/cubes were around 20% compared to 70–75% for powders. The article also presents a comprehensive comparison of fine and coarse fractions of date fruit powders for various physical parameters.

Samples of nine home-made, commercial Chami cheese samples were analyzed for chemical composition, texture, and rheology. The samples showed large variations in moisture, protein, fat, ash, mineral contents, and pH values. Fat content, fatty acid composition, and differential scanning calorimetry analyses suggested addition of extra fat in some samples either butter or vegetable oil. The sodium content in the 9 cheese samples varied from 223-2411 mg/kg with three samples having very high contents 1756, 2024, and 2411 mg/kg indicative of added salt. The sample with the low moisture content (60.9%) was the hardest among the cheeses. Rheological examination showed the Chami cheese samples of more elastic than viscous behavior.

Camel milk (CM) is gaining scientific attention due to its potential health and therapeutic benefits. Fermented drinkable yogurts (labans) were prepared from CM and bovine milk (BM) using mixed Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus bacteria supplemented with 1 of 2 hydrocolloids: pectin (0.1-0.3%) or sodium alginate (0.1-0.5%). The different labans were compared by studying their acidity and rheology as well as their structural and sensory properties. The CM and BM labans had titratable acidity values that ranged from 0.85 to 1.27 and 0.61 to 0.93%, respectively. Pectin at 0.2% enhanced the rheological properties of BM labans, but had no effect in CM labans. Sodium alginate at 0.3% and 0.5% increased viscosity, elastic or storage modulus (G'), and viscous or loss modulus (G″) values for both types of laban. Scanning electron microscopy indicated that the CM laban contained lower levels of "spike-like structures" than BM laban, and that the addition of hydrocolloids improved this effect. Quantitative descriptive sensory analysis showed that CM labans fortified with either 0.2% pectin or 0.3% sodium alginate were comparable to commercial BM laban in viscous mouthfeel. Fortified CM labans were more acidic and had stronger flavors than unfortified samples. Overall, this study demonstrated that the addition of sodium alginate or pectin at intermediate levels permits production of palatable CM labans of a satisfactory viscous consistency.