Date Waste Research Articles

Optimization of Sugar Extraction Process from Date Waste Using Full Factorial Design Toward Its Use for New Biotechnological Applications.

In Tunisia, the date industry generates a large quantity of waste, raising environmental concerns. However, dates are rich in sugars, which offer a renewable source of nutrients for various applications. In this study, sugar extraction from two low-grade pitted date fruits (Alig and Kentichi) under ultrasound, was optimized using full factorial design. At 40 °C, for20 min, and with a liquid-to-solid ratio of 10 mL/g, the optimum sugar contents were 60.87% and 50.79% for the varieties Alig and Kentichi, respectively. The date extracts were chemically analyzed, revealing low fat and protein contents, but significant polyphenol and mineral contents in both varieties. HPLC-IR analysis revealed more inverted sugars (glucose and fructose) in the Alig variety and more sucrose in the Kentichi variety. FTIR and SEM analysis showed the efficiency of the ultrasonic treatment of the biomass in terms of improving mass transfer diffusion through ultrasonic cavitation. Thus, ultrasound-assisted extraction constitutes an effective method for the recovery of sugar from date waste.

ECO-FRIENDLY BIONANOCOMPOSITE BASED ON BIOSYNTHESIZED POLY(3-HYDROXYBUTYRATE-CO-3-HYDROXYVALERATE) REINFORCED WITH Ni-CuO NANOPARTICLES FOR REMOVAL OF BRILLIANT GREEN

Ni-doped Copper oxide (Ni-CuO) nanoparticles have been synthesized from Arabic Gum. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) polyester was biosynthesized by the microorganism Haloferax mediterranei utilizing date waste as carbon source. The produced Ni-doped copper oxide (Ni-CuO) nanoparticles have been incorporated with different percentages into the PHBV matrix. The produced bionanocomposites were achieved with different percentages of the nanoparticles: 1%, 3%, 5% and 10%, and were referred to as PHBV/Ni-CuO(1,3,5,10%). FTIR, TGA, XRD, SEM and EDX techniques have been used to study and characterize the synthesized bionanocoposites. In addition, the prepared nanocomposites were studied for their efficiency as solid phase adsorbents for Brilliant Green (B.G.) dye from water resources under different conditions. The prepared nanocomposites were found to be very efficient and promising solid phase adsorbent materials to treat water samples for the purpose of dye removal. The percentage of the removed dye increased from 45.6% to 97.7% as the PHBV/Ni-CuO(10%) nanocomposite amount increased from 10 mg to 70 mg per 25 mL of water sample. The dye removal percentage reached an equilibrium in 90 min. Natural water samples from three different sources have been tested against the Ni-CuO/PHBV(3%) nanocomposite as solid adsorbent for the B.G. removal, and the results showed >90% dye removal in all cases under the optimum experimental conditions.

Comparison of acid and hydrothermal pretreatments of date waste for value creation

The production of date syrup yields a substantial amount of date press cake (DPC), fibrous and moisturising material with great potential for generating value through bioprocessing. However, the recalcitrant structure of DPC affects the yield of products in bioprocesses. To boost the accessibility of the structure as well as increase the soluble fraction of carbohydrates and facilitate further enzymatic hydrolysis, hydrothermal and dilute acid (0.5% (v/v) sulfuric acid) pretreatments as cost-effective and feasible methods were applied on DPC at relatively low temperatures (80, 100, 120 and 140 °C) and reaction times (60 and 90 min). The success in pretreatment was then evaluated by a post-enzymatic treatment using an enzyme cocktail of cellulases and hemicelluloses. Based on total accessible sugar with minimum produced inhibitors, an optimal operating condition was considered acid pretreatment at 120 °C for 90 min with a 55.02% increase in total sugar yield. To explore the potential use of pretreated DPC, an anaerobic digestion was conducted on untreated and acid-pretreated DPC at 120 °C for 90 min. The results showed that pretreatment increased the total bioproduct yield, including hydrogen, ethanol, and volatile fatty acid yields, by 59.75%. This demonstrates the significant impact of pretreatment on product yields in a bioprocess.

Production of low-cost lactic acid from dairy wastes and dates wastewater and bioactive silver-poly (lactic acid) nanocomposite for biological applications

L-Lactic acid-producing Lactobacillus lactis and L. plantarum were isolated from date wastes. The fermentation process was optimized using a one-variable-at-a-time approach. Dairy wastewater and wastewater from the date industry were utilized as low-cost culture media to produce lactic acid. The selected two bacterial strains were co-cultured in wastewater medium to produce L-lactic acid and D-lactic acid. Lactic acid production was significantly improved by glucose (carbon source), yeast extract (nitrogen source), initial inoculum level, and polysorbate 80. A central composite design and response surface methodology were used to optimize the variables and their levels to improve lactic acid yield. The supplemented yeast extract, glucose, and polysorbate 80 improved lactic acid. The predicted variables and their levels for maximum lactic acid production were glucose (67.5 g/L), yeast extract (10.28 g/L), and polysorbate 80 (0.48 mL/L). The prepared nanocomposites exhibited antibacterial activity against foodborne bacterial pathogens. The structural properties of the silver-polylactic acid nano compost materials were determined. The characterized compost materials exhibited a peak absorption wavelength of 430 nm. The silver and poly(lactic acid) were characterized using X-ray diffraction analysis and were 30 to 50 nm in size.

Novel strategy to elevate solid state fermentation to produce alkilophilic endoglucanase using date waste feedstocks and peapod extract based nutrient media and expired probiotic strain: Application in fermentable sugar production

Solid waste generation and its impactful management are among the most raised environmental concerns seeking sustainable alternatives in the form of value addition. In this study, a novel strategy has been presented towards enhanced bacterial endoglucanase (EG) production under solid state fermentation (SSF). The EG was produced using the waste probiotic juice of the bacteria Lactobacillus casei strain Shirota on a substrate of waste date pulp and seeds in co-fermentation mode. Additionally, peapod extract has been applied as a nutrient medium to maintain moisture in place of commercial media in SSF. Further, for enhancement in enzyme production, the impact of incubation temperature and pH of the SSF medium have been studied to obtain optimum enzyme activity. Under optimum conditions, bacteria produced 17.2 U/mL EG at a temperature of 37 °C and a pH of 8.0. The raw EG showed pH and thermal stability up to 5 h at 60 °C and pH 8.0. Furthermore, the enzymatic hydrolysis of date pulp released 67.71 g/L fermentable glucose obtained in 24 h of the reaction at 60 °C and pH 8.0. This work may have great significance in the areas of solid waste management and microbe-mediated value addition of waste biomass in the context of hydrolytic enzyme production for biorefinery applications.

Exploitation of spoilage dates as biomass for the production of bioethanol and polyhydroxyalkanoates

The exploitation of agri-food wastes is of great importance for environmental and economic reasons. Date wastes are attractive biomasses that could be used as a carbon source for the growth of microorganisms to obtain added-value products. In this work, spoilage date syrup, containing 102.01 and 101.00 g/L of glucose and fructose, respectively, was assessed as a feedstock for the production of bioethanol and polyhydroxyalkanoates (PHAs) by Saccharomyces cerevisiae MEL2 and Cupriavidus necator DSM 545, respectively. The waste date syrup was first evaluated as a carbon source for microbial growth and resulted to sustain the growth of both strains. 47.95 g/L of ethanol, corresponding to the 93.52% of the theoretical yield, were obtained from the fermentation of date syrup by S. cerevisiae MEL2, here adopted as a proficient bioethanol yeast strain. Furthermore, C. necator DSM 545, a well-known PHAs-producer, was able to accumulate up to 79.20 % (w/w on dry mass) of PHAs. This study demonstrates that bioethanol and PHAs can be obtained from date wastes, contributing to developing cost-effective exploitation of these residues with economic and environmental advantages.

Valorization of Date Fruit (Phoenix dactylifera L.) Processing Waste and By-Products: A Review

The date is a well-established and important crop that holds economic significance. However, a substantial amount of waste in the form of low-grade dates and date pits is generated and accounts for 10 to 15% of the total production. Given the substantial amount of nutrients in these by-products and the large volume of waste generated, there is a promising opportunity to utilize them to create valuable commodities like fiber and phenolic compounds, which hold a high market value. This review presents a summary of the chemical and nutritional composition of dates and their by-products and aims to investigate the possibility of utilizing date processing by-products and waste as an eco-friendly resource for various chemical and biological processes like composting and extraction of value-added compounds, as well as providing insight into the date processing industry and typical methods employed for the beneficial use of date waste. In addition, this review also addresses the current challenges and future perspectives in date waste valorization expectations.

Techno‐economic viability analysis of a downdraft gasification system for hydrogen production from date molasses waste in Iraq

AbstractIn the current study, a fixed‐bed downdraft gasifier was used, in addition to gas cleaning and treatment units, to evaluate hydrogen production from the waste from a date molasses factory. Date pits and pomace were gasified at a temperature of 800°C with oxygen‐rich air and standard air as the gasifying agents. Simulations were performed using the Cycle‐Tempo simulation tool. The impact of many process parameters (air–fuel ratio, gasification temperature, moisture content, oxygen concentration and temperature of the water–gas shift) on gas composition was investigated. The economic evaluation of hydrogen production is also discussed in this paper. Depending on the operating conditions, the results indicate that gasification of biomass in oxygen‐rich air improves hydrogen yield compared with air gasification of biomass. Over the range of operating conditions examined, the maximum hydrogen production reached 45.86% for pits and 35.81% for pomace from gasification with oxygen‐rich air while the H2 content reached 36.71 and 28.72% respectively for air gasification of pits and pomace. The cost analysis for the date waste gasification unit showed that the hydrogen production cost is $3/kg for date pits and $4/kg for pomace. The production of hydrogen from date molasses manufacturing waste helps to lessen reliance on fossil fuels and is an environmentally beneficial alternative source of renewable energy.

Dried Date (Phoenix dactylifera L.) Meal Inclusion in the Diets of Broilers Affects Growth Performance, Carcass Traits, Nutrients Digestibility, Fecal Microbiota and Economics

The availability of suitable feedstuffs for poultry nutrition is a significant challenge faced by the global poultry production industry. This issue has been exacerbated by the shift towards using grains for biofuel production, leading to a subsequent rise in feedstuff prices. The study aimed to assess the impact of different levels of dried date wastes in the diet of broiler chicks on their growth, carcass characteristics, nutrient digestibility, fecal microbiota and economics. A total of 240 day-old broiler chicks (Ross 308/Ross 308 FF) were divided into five experimental groups and fed 0, 3, 6, 9 and 12% of dietary date meal (DDM). The formulated diets were provided to chicks for a duration of 35 days. The findings of the study indicated that chicks fed with a diet containing 9% dried dates exhibited a significantly (p < 0.05) higher increase in body weight compared to the control group by the end of the study period. Additionally, dressing percentage, carcass weight, leg weight and breast weight were notably higher (p < 0.05) among birds that consumed the 9% dried dates diet. Moreover, the digestibility of dry matter, crude protein and ether extract showed a significant (p < 0.05) increase in birds that were fed a 9% dried dates diet. Furthermore, DDM at 9% experienced significantly (p < 0.05) higher levels of Lactobacillus and decreased (p < 0.05) the level of E. coli count. Similarly, economically, birds supplemented with 9% DDM exhibited significantly (p < 0.05) higher profit compared to the control. In conclusion, the results of this study suggest that broiler chicks fed with a diet including 9% dried date waste experienced improved growth performance, enhanced carcass quality, supported digestibility of nutrients, elevated the count of fecal Lactobacillus, reduced E. coli count and economics.

Probiotic Lactobacillus strains isolated from date waste and wastewater for the kidney stone, intestinal oxalate-degradation and antioxidant activity

Lactic acid bacteria (LAB) are probiotic organisms and are promising alternatives to manage kidney stone problems. Oxalate digesting LAB was screened from date wastes and date wastewater. LAB was isolated using De Man, Rogosa and Sharpe agar (MRS agar) medium and was subjected to oxalate degradation assay in a calcium oxalate plate. The strain was further subjected to assay for its capacity to tolerate acidic pH value and bile salt. Then, anti-urolithiatic activity assay was carried out by in vitro analysis. Based on preliminary characteristics, among 62 oxalate degrading strains, twenty-four strains exhibited a greater than 10 mm zone. The potent bacterial strains were identified as Lactobacillus cassei, L. acidophilus, L. gasseri and L. fermentum. Isolates from date wastes showed better antagonistic properties towards bacterial pathogens. At 50 µg Calcium oxalate concentration, 75.6 ± 0.865 degradation was achieved by L acidophilus. LAB isolated from date waste showed promising anti-urolithiasis activity. Hence, date waste may serve as a potential source for LAB probiotics to treat hyperoxaluria.

VALORIZATION OF DATE WASTE (HMIRA CULTIVAR) FOR THE PRODUCTION OF BIOALCOHOL AND BIOGAS

During the past years, bioethanol and biogas have a significantly development, they are fuels obtained from the fermentation of sugar plants and anaerobic digestion of organic compounds respectively, The major advantage of these biofuels is the reduction of gases Global Warming effect. In this work, two steps were performed: the first was the production of bioethanol from date waste by the fermentation. In the second stage, anaerobic digestion experiments are contucted in four digesters, each with a one litre capacity and a working volume of 600 mL. The digstion pricess takes place at 37°C for a duration of 45 days. To prepare the digesters, 10 g of volatile solids (VS) from the substrate are used. Alkaline pretreatment is employed with NaOH concentrations of 6%, 12%, and 18% (weight/weight, w/w) based on the substrate’s volatile solids (VS). We obtained a yield of 360 mL of bioethanol of 93 ° per 1 kg of date waste. For the anaerobic digestion, the obtained results show that a 12% NaOH is the best concentration with a 1178 mL CH4/gVS.

Statistical Optimization of Lactic Acid Production by the Lactococcus lactis DBH10 Strain in a New Culture Medium Based on Date Waste (DJM), Using Response Surface Methodology

Statistical Optimization of Lactic Acid Production by the Lactococcus lactis DBH10 Strain in a New Culture Medium Based on Date Waste (DJM), Using Response Surface Methodology

Enhanced hydrogen and methane production from date fruit wastes using semi continuous two-stage anaerobic digestion process with increasing organic loading rates

Biological conversion of date wastes under continuous conditions is a challenge due to their high content of biodegradable organic matter. In this study, hydrogen (H2) and methane (CH4) production in a two-stage process to increase the energy recovery from date pulp wastes (DPW) was investigated. In the first stage, the effect of increasing organic leading rate (OLR) on dark fermentation (DF) performances was evaluated in a semi continuously stirred tank reactors (SCSTR) without nutrients addition. The highest volumetric H2 production rate (VHPR) and specific H2 yield (SHY) of 0.76 L/L.d and 81 LH2/kg volatile solid (VS), respectively were achieved at high OLR of 11.74 gVS/L.d. In the second stage, the DF effluent was used as substrate to feed the SCSTR of anaerobic digestion (AD). The highest volumetric methane production rate (VMPR) of 2.92 L/L.d was achieved with a high OLR (4.25 gVS/L.d) and short hydraulic retention time (HRT, 8 days), producing specific methane yield (SMY) of 530 LCH4/kgVS. Thus, the two-stage process can be an effective strategy for high rate renewable energy recovery (13 kJ/gVSinlet) and organic waste processing.

Characterization analysis of date fruit pomace: An underutilized waste bioresource rich in dietary fiber and phenolic antioxidants

Date fruit pomace (DFP), an abundant byproduct of the date syrup industry, is currently underutilized. It is either fed to animals or landfilled where it ferments, causing serious environmental issues. Proper waste management through valorization strategies is required to reduce the environmental impact of date waste and foster the transition of the date processing industry towards sustainability. The implementation of valorization strategies requires characterizing the DFP composition. Herein, four DFP samples of Emirati varieties were characterized in terms of compositional and functional properties. The fresh DFPs contained moisture (∼60.0 g/100 g). On a dry matter basis, DFPs contained total dietary fiber (∼45.5 g/100 g), residual sugars (∼35.3 g/100 g), protein (∼10.6 g/100 g), ash (∼4.1 g/100 g), and fat (∼1.3 g/100 g). They were also rich in nutritionally important elements such as potassium (∼145.7 ppm), calcium (∼46 ppm), phosphorus (∼28.7 ppm), and magnesium (∼26.7 ppm). The total phenolic content varied from 170 to 260 mg gallic acid equivalents GAE/100 g, making DFP a good source of antioxidants. Scanning electron microscopy measurements revealed the presence of fibrous bundle-like structures, whose thermal stability was confirmed by thermogravimetric analysis, showing the dominance of insoluble over soluble fiber. Higher water- and oil-holding capacities were found for dried desugared pomace. The high fiber, phenolic, and elemental content highlight the high nutritional value of DFP, which can be used as dietary supplement, while its sugar content can be used to produce value-added biochemicals via fermentation. Thus, DFP may represent a valuable bioresource for food and non-food applications.

Theoretical study of a downdraft gasifier, microturbine, and organic Rankine cycle fuelled by date molasses waste for distributed generation applications in Iraq

AbstractThe main objective of this work is the modeling of a combined heat and power (CHP) system that transforms waste from manufacturing date molasses in the Babylon province in central Iraq into electrical and thermal energy. A compact CHP facility that uses date waste (pomace and pits) as a feedstock is the subject of theoretical modeling and simulation research. The planned power plant consists of a downdraft gasifier, a microturbine (MT), and an organic Rankine cycle engine (ORC) as a bottom unit to maximize electric generation by recovering the MT exhaust gas heat and achieving a maximum electric output. The net electric production is 361.68 kW (280 kW from the MT unit and 81.68 kW from the ORC unit). To determine the best‐working fluid for the ORC system as a whole, three working fluids, including isopentane, benzene, and R113, were investigated. The temperature difference between the heat source and the fluid's boiling point is a key factor in choosing a more appropriate ORC working fluid. Isopentane is the most suitable working fluid for CHP applications, according to the findings of the simulation. The electric efficiency achieved is 30%, and the overall efficiency of the CHP plant was 56.87% from the gasification of date pits. The simulation results showed a satisfactory producer gas lower calorific value of 3.92 MJ k‐g‐1 for date pomace and 4.65 MJ k‐g‐1 for date pits, and cold gasification efficiencies of 73% and 76% for pomace and pits, respectively. © 2023 Society of Industrial Chemistry and John Wiley & Sons Ltd.

Effect of Carbon Sources on Glutamate Production from Corynebacterium glutamicum 2262

A comparative study between natural and synthetic environments is carried out by realizing six fermentation experiments in batch culture. The objective of this study is to consider the effect of carbon sources on growth and the production of glutamic acid by Corynebacterium glutamicum 2262. The difference between the culture media lies in the carbon source. Two natural environments of date juice, one of which is treated with invertase to hydrolyse sucrose with a concentration of total sugars of 88 g/L. Four synthetic media with a concentration of 34 g/L sugars: medium containing mixed sugars (glucose + fructose + sucrose) with rates proportional to that of date juice, the other three media are composed of a single sugar (either glucose, fructose, or sucrose). The results showed that Corynebacterium glutamicum is able to use the three sugars whether they are single or mixed, although the best results of glutamate production (8.41 g/L) are obtained on the mixture of three sugars, which explains the interest and valorisation of date waste. On the other hand, the date juice-based media are shown to have a glutamate concentration of 7.98 g/L during the hydrolysis of sucrose of date juice.

Comparing the uses of available labor and capital in diversified farming systems in Drâa oases (Morocco)

In this study, uses of labor were characterized using the ‘Work Balance’ method in a sample of 17 oasis farms. The results showed that almost 44% of total uses of labor are devoted to livestock, while the remainders 56% are used for crops. The labor required to raise livestock was almost entirely (92%) provided by family member, whereas that required for crops was mostly provided by hired laborers. Date palms are the pillar of the oasis farming system and enable the positive synergies of this mixed crop/livestock system. Date wastes and cereal straw are used to feed the animals, while the livestock supplies the farmers with milk and meat, and their sale ensures the purchase of agricultural inputs in the period preceding date harvest. Our results show that labor is an essential component of oasis farming systems, as it provides opportunities to achieve a circular economy. Otherwise, on farms specialized in crops that have no livestock, the economic efficiency of labor is higher, thanks to higher investments. Taken together, these results suggest that there are ways to improve the efficiency of the uses of labor on oasis farms.

Biosynthesized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) as biocompatible microcapsules with extended release for busulfan and montelukast

An extended release dosage form based on encapsulating the challenging drug busulfan within microspheres of the biodegradable, biocompatible and biosynthesized poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) polyester was achieved. The used (PHBV) polymer was biosynthesized by the halophilic archaeon Haloferax mediterranei from date waste biomass as feed-stock. PHBV microspheres of 1.2–2.1 μm diameter were successfully fabricated and loaded with busulfan with an encapsulation efficiency of 29.2 ± 0.2%. In addition, PHBV microspheres of 1.5–3.5 μm diameter and loaded with montelukast sodium (MK) drug were also fabricated with an encapsulation efficiency of 16.0 ± 0.4%. The double-emulsion solvent evaporation method was used to fabricate the drug-loaded microspheres. The drug-loaded microspheres have been characterized by XRD, FTIR and SEM, and confirmed to be successfully fabricated. The drugs in vitro release profiles have shown extended release for up to 3 days in case of busulfan and 8 h in case of montelukast sodium. The in vitro release profiles for busulfan and montelukast suggest that these drug-loaded microcapsules can be efficiently used as new dosage forms to solve the current issues of busulfan administration protocols, and to introduce a new dosage form for montelukast with extended release performance.

Optimization of Monascus Pigment Production on Date Waste Substrates Using Solid State Fermentation

Background and Objective: Monascus purpureus can produce pigments with light yellow to dark red colors. It includes several health properties. In this study, a low-cost process has been developed for the production of natural pigments from filamentous fungi through solid-state fermentation using cheap substrates. Material and Methods: In this study, cultivation conditions were optimized for the production of red Monascus pigment by Monascus purpureus ATCC16362 using response surface methodology. Incubation time (7-24 days), date waste syrup concentrations (1-69%) and NaCl contents (7-13.75 g.l-1) were analyzed base on central composite design. Results and Conclusion: The maximum production of red Monascus pigment (5.10 AU.g-1) by Monascus purpureus was achieved using 55% date waste syrup concentration, 7 g.l-1 NaCl and incubation time of 21 days. At optimum conditions, µmax of 6.2 × 10-3 (mg.g-1.h-1), pigment efficiency of 0.238 (AU.g-1.day-1), conversion factor of biomass in red pigments of 0.25 (AU.mg-1.g-1), glucose utilization of 93% were achieved. Results showed that use of date waste syrup and wheat straw as substrates were successful in solid state cultivation for the production of red pigments by Monascus purpureus. Conflict of interest: The authors declare no conflict of interest.

Date (Phoenix dactylifera L.) by-Products: Chemical Composition, Nutritive Value and Applications in Poultry Nutrition, an Updating Review.

Simple SummaryThe demand and price of feed/feed stuffs was greatly altered after the COVID-19 crisis, showing great interest on depends on local feed stuffs and a decrease in the imported ones. Date palm (Phoenix dactylifera L.) is a common crop in arid and semiarid regions for production of date fruits. This updating review provides the recent knowledge on the use of date palm by-products and improving their utilization in poultry rations. This article focuses on the chemical composition, amino and fatty acids, mineral content, growth performance, economic aspects and nutritional potential in comparison with widely used corn and barley grains in poultry.Several by-products, such as whole cull dates, date stones (also called pits, seeds, kernels), sugar-extracted date pulp, are produced from date fruit processing industries. These by-products, particularly date stone meal represent 10 to 20% of the whole dates are wasted, causing environmental issues. However, the date stone is rich in various nutrients, such as nitrogen-free extract, fiber, fat, and minerals, which could be used as an alternative feed source in poultry nutrition. However, the high fiber content in date stone meal restricts its use in poultry diets. Whole date wastes and date pulp have lower protein, fiber and fat content than those in date stone meal. Several studies have investigated the use of date stone meal and other by-products as a replacement of dietary corn and barley on feed intake, growth, feed efficiency, and nutrient utilization in poultry. The compilation of results obtained from different studies indicates that date fruit by-products, particularly date stone meal, could be incorporated up to 10% levels, replacing corn or barley grains without hampering production performance, and this could reduce the production cost. Moreover, the use of date stone meal at lower levels (5–10%) sometimes shows better growth performance, probably due to the presence of bioactive principles such as antioxidants and phenolic compounds. The use of date stone meal in poultry diets may be practically important under certain circumstances not only under the COVID-19 crisis due to the lockdown of airports, dry ports, ports and traffic restrictions, but also in countries with a limited supply of classical feed resources and which depend on imported ones. Finally, it can recommend that using date stone meal (DSM) up to 5–10% in poultry diets positively affect the productive performance. Due to the variability in the nutritive value of the DSM, developing a formula for metabolizable energy (ME) of DSM = a (intercept) − b (slope) × crude fiber (CF) content should be considered to improve the precision of feed formula for poultry. However, the nutritional value of DSM might not only depend on crude fiber but also on other compounds.