Quality and mechanical resilience are crucial for reducing losses in fruit production and for supporting food chains. Indeed, integrating empirical data with rheological models bridges gaps in fruit processing equipment design. Therefore, the objective of this research is to analyze the relationship between the mechanical and physical properties of seven economically important fruits—nectarine, kiwi, cherry, apple, peach, pear, and apricot—to assess their mechanical behavior and post-harvest quality. Standardized compression, creep, and puncture tests were conducted to establish mechanical parameters, such as rupture force, elasticity, and deformation energy. Physical characteristics including size, weight, density, and moisture content were also measured. The results indicated significant differences among the various categories of fruits; apples and pears were most suitable for mechanical harvesting and long storage periods, whereas cherries and apricots were least resistant and susceptible to injury. Correlations were high among the physical measurements, tissue firmness, and viscoelastic properties, thereby confirming structural properties’ contribution in influencing fruit quality and handling efficiency. The originality of this research is in its holistic examination of physical and mechanical properties under standardized testing conditions, thus offering an integrated framework for enhancing post-harvest operations. These findings offer practical insights for optimizing harvesting, packaging, transportation, and quality monitoring strategies based on fruit-specific mechanical profiles.

The physico-mechanical properties of date fruit varieties can indicate their quality and freshness. These properties, which include firmness, moisture content, and mechanical resistance, are closely linked to the fruit’s overall quality and can be used to assess its ripeness and suitability for consumption. Therefore, the current study evaluated the physico-mechanical properties of three date varieties—Sukkari, Khalas, and Saqie—across different ripening stages to enhance food quality and optimize postharvest handling. The study uniquely focused on how ripening stages affect the stress–strain behavior of dates, offering new insights into their mechanical resistance, deformability, and structural stability, all of which are critical parameters for maintaining food quality during storage, transportation, and processing. Significant changes in physical characteristics, including size, mass, moisture content, and density, were observed as the fruit progressed through ripening stages. Sukkari showed the most notable decrease in moisture content, from 61.8% at the Khalal stage to 17.3% at the Tamar stage, resulting in softening and reduced mechanical resistance, potentially impacting shelf life and consumer acceptance. Khalas exhibited a more gradual decline in mechanical properties, with moisture content dropping to 24.6%. At the same time, Saqie demonstrated minimal changes in mechanical properties and moisture content, suggesting better structural and nutritional quality retention. Additionally, the dynamic coefficient of friction increased with temperature and pressure at the Tamr stage, with Sukkari showing the highest values (up to 0.496), followed by Khalas (up to 0.451) and Saqie (up to 0.406). This study introduced the concept of variety-specific differences in frictional behavior, providing valuable insights for improving mechanical processing, reducing physical damage, and preserving date fruits’ nutritional and sensory quality. In conclusion, findings highlight the importance of variety-specific mechanical profiling in improving processing protocols, reducing postharvest losses, and maintaining the nutritional and sensory quality of date fruits for industrial-scale operations.

Growing health consciousness drives demand for convenient, nutrient-dense snacks. This study evaluates five Sukkari date-mixed-nut bar formulations (DNB1–DNB5; date/nut ratios 40:60–80:20) through comprehensive biochemical and nutritional analyses. Macronutrient profiling showed that higher date ratios increased moisture and carbohydrates, whereas higher nut ratios enhanced protein, fat, and caloric density. Mineral assays revealed progressive increases in calcium, phosphorus, magnesium, and trace elements as date content decreased. The assessment of phytochemicals and antioxidants demonstrated that total phenolics, flavonoids, and radical-scavenging activities peaked in nut-rich bars, declining by ~50% in date-rich bars, underscoring nuts’ dominant antioxidant role. HPLC profiling identified catechol and vanillic acid as the major phenolics, with optimal release and retention at the 60:40 ratio (DNB3). Amino acid (AA) analysis confirmed positive correlations between nut content and total/essential AAs; DNB1–DNB2 achieved favorable essential-to-nonessential AA ratios (0.56–0.59) and higher protein quality indices. Fatty acid (FA) composition analysis revealed that oleic acid was identified as the major constituent across all formulations, coupled with optimal omega-6/omega-3 ratios. GC-MS analysis identified a total of 31 volatiles, mainly benzene derivatives and FA methyl esters. Results also revealed that notable variations attributed to different date/nut ratios significantly alter aroma profiles, with DNB3 yielding the most remarkable diversity of health-associated volatiles. Results from PCA and hierarchical clustering suggest that a single dominant dimension (PC1, 94.47% variance) governs compositional differences among the five date bar formulations, reflecting deliberate variation in ingredient proportions. The evidence suggests that DNB3’s (60:40 Sukkari date to mixed nut ratio) delivers balanced macro-nutrients, robust antioxidants, and diverse bioactives, positioning it as a health-promoting functional snack, aligning with its suitability for athletes, clinical nutrition applications, and health-conscious populations. These findings support the commercial development of optimized date-nut bars as nutrient-dense functional snacks, and future work should focus on scale-up production, shelf-life stability, and assessing in vivo bioavailability.

The combined pretreatment of ultrasound irradiation, urea, and sodium hydroxide was explored to increase the extraction and delignification of cellulose from spent coffee grounds (SCGs), shortening the extraction time. The impacts of different experimental conditions, namely alkali concentration (5 vs. 10%), urea addition (0 vs. 3%), and ultrasound aid (30 min, 40 kHz, 150 W), on the physicochemical characteristics of the extracted cellulose were determined. The first characteristic of the raw biomass was its high lignin content (30.4%), necessitating a rigorous delignification process. To confirm this, samples were further analyzed by FTIR, XRD, TGA, and SEM. The successful elimination of non-cellulosic material, as indicated by the disappearance of the carbonyl stretch at 1730 cm⁻¹ and attributed to hemicellulose and pectin, was confirmed by FTIR. The XRD results revealed that while the individual application of ultrasound yielded the highest apparent crystallinity index (64.5% for sample B), the synergistic low-alkali combination with urea (sample F) resulted in a lower, controlled crystallinity index (56.2%). This indicated that the coexistence of urea and ultrasound induces significant fiber swelling and localized hydrogen-bond disruption, as well as highly efficient chemical purification. The thermal analysis revealed that all samples had high thermal stability with a maximum degradation temperature (T_max) between 316 and 322 °C, which can be used in composites. The process was visually confirmed by morphological analysis carried out under SEM, which revealed a progressive surface erosion of the compact lignocellulosic matrix into cellulose-rich samples treated with ultrasound.

Dates are an important national resource in Saudi Arabia, with significant efforts focused on increasing production, enhancing quality, and utilizing surplus dates for health-oriented food products. This study investigates the technological role of powdered low-quality Sukkari dry dates as a sugar substitute in balanced functional biscuits that are rich in fiber and minerals while being low in calories. The study assessed the effects of substituting sugar with powdered dates at levels of 25%, 50%, and 75%, focusing on the optimal substitution ratio for high-quality biscuits. The findings revealed that the powdered date substitution influenced the dough's rheological properties, including a decrease in water absorption, an increase in dough formation time, and a reduction in mixing tolerance at higher substitution levels. The sugar reduction led to a decrease in calories and carbohydrates, while protein and ash content increased. Color analysis showed reduced lightness and yellowness, with an increase in redness and darker tones as the substitution level rose. Sensory evaluations indicated that biscuits with 25% substitution were highly acceptable, scoring 94.90%, comparable to the control sample's 97.15%. Biscuits with up to 50% substitution were also deemed acceptable, highlighting the potential of Sukkari dates as a balanced functional and healthier sugar alternative in biscuit production.

This study explored the utilization of date powder produced from non-marketable Sukkari and surplus dates as a natural sugar substitute in milk chocolate, with the dual objectives of improving product quality and reducing Saudi Arabia’s reliance on imported sugar. Molding chocolates were formulated with 10%, 20%, and 30% sugar substitution, while coating chocolates contained 20%, 40%, and 60%. Physical, chemical, and sensory properties were assessed immediately after production and following six months of refrigerated storage. Increasing substitution levels led to higher viscosity, with peak values observed at 30% in molding chocolate and 60% in coating chocolate. Ash and moisture contents also rose with substitution, whereas fat, protein, and carbohydrate levels remained largely unaffected. Energy content declined as substitution increased, and no significant differences were detected in peroxide or acid values between control and treated samples throughout storage. Sensory evaluations confirmed that molding chocolate with up to 20% substitution and coating chocolate with up to 40% substitution maintained comparable acceptability to control samples both initially and after storage. Overall, the findings recommend sugar replacement with date powder at 20% in molding chocolate and 40% in coating chocolate to achieve high-quality, nutritionally enhanced products with stable sensory and storage characteristics.