Iranian Food Science and Technology Research Journal

Abstract This research focuses on the application of response surface methodology (RSM) in the optimization and mathematical modeling of potato slice drying in a laboratory-scale convective dryer assisted by incandescent lamps. The relationships between the independent variables in terms of temperature (°C), incandescent lamp power (W), and slice thickness (mm) were studied in relation to the responses of interest or dependent variables, consisting of drying time (min), overall product acceptance, and effective water diffusivity (m²s^-1). A high value of overall product acceptance is considered to be the optimizing parameter for drying potato sheets. The response surface methodology was applied using a rotational central composite design (RCCD) to optimize the dependent variable. Second-order polynomial regression equations were obtained for each response variable. The optimal drying conditions were established for the maximum value of overall acceptance and were: 69.33 °C, 328.80 W, and 4.40 mm, for temperature, power, and thickness, respectively, with the optimized drying time for the product being approximately 130 min. Drying was carried out during the decreasing drying rate period, and the results show that the addition of energy from incandescent lamps reduces the drying time by 30%. Using the Quasi-Newton Simplex method, the constants of the mathematical models were determined to simulate the drying curve, and the conjugate model of two terms and five constants presented the best fit. Using Fick's law equation, the effective diffusivity of water ranged from 4.48x10^-10 to 3.38x10^-9 m²s^-1, and under optimal drying conditions, it was 2.46x10^-9 m²s^-1. The information obtained contributes fundamentally to the development of dryers and the control of drying processes on a commercial and industrial scale.

Abstract The growing demand for functional foods has encouraged with incorporation of natural, nutrient-rich ingredients into traditional products to support health and wellness. Foxtail millet, a gluten-free grain rich in protein, fiber, and micronutrients, and orange peel powder, a by-product abundant in dietary fibre and bioactive compounds, were used to develop cookies with functional properties. This study aimed to develop and evaluate functional cookies prepared from foxtail millet enriched with orange peel powder. Five formulations were produced with 49:1, 48:2, 47:3, 46:4, 45:5 of foxtail millet and orange peel powder for sample 1 to sample 5 while the control sample had 50:0. The samples were analyzed for proximate composition, antioxidant activity, microbial safety, and sensory properties to determine the optimal level of incorporation using standard methods. The results revealed that for proximate composition, protein content ranged from 11.7% to 7.2% for sample 1 to sample 5 while the control sample had 11.9%. Fat content ranged from 20.5% to 19.3% for sample 1 to sample 5 while the control sample had 20.7%. Crude fibre content ranged from 2.8% to 4.8% for sample 1 to sample 5 while the control sample had 2.1%. Ash content ranged from 1.10% to 1.54% for sample 1 to sample 5 while the control sample had 1.04%. Moisture content ranged from 2.61% to 4.25% for sample 1 to sample 5 while the control sample had 2.5%. Nutritional analysis indicated a progressive enhancement in dietary fiber and antioxidant activity, contributing to improved digestive health and free radical scavenging capacity. Sensory evaluation showed the optimal orange peel powder concentration (2%) for sensory overall acceptability. The study demonstrated that incorporating orange peel powder significantly enhances the nutritional and functional attributes of cookies.

Abstract Red ruby grapes are known for their rich anthocyanin content and nutritional and medicinal properties, but their high perishability limits postharvest shelf life. Current research highlights the potential of advanced packaging techniques, such as modified atmosphere packaging (MAP), and nanotechnology to enhance the quality and shelf life of fresh products. This study aims to investigate the combined use of these technologies to maintain the quality and increase the shelf life of red ruby grapes. This study evaluated the effectiveness of polyethylene packaging films containing silver nanoparticles and titanium dioxide with modified atmosphere packaging (50% CO₂ + 5% O₂ + 45% N₂). The experiments were conducted under three temperature conditions (25°C, 15°C, and 4°C) and over a 28-day storage period. Samples were assessed at five intervals (0, 7, 14, 21, and 28 days) for quality attributes and microbial loads. This approach was chosen to address the challenges of microbial growth and quality deterioration in grapes stored at different temperatures. The findings showed a continuous decrease in anthocyanin content and color intensity during the storage period, alongside an increase in soluble solids. Microbial analysis showed higher mold and yeast counts in grapes stored at 25°C and 15°C compared to those stored at 4°C. Packaging with MAP and nanocomposite films containing silver nanoparticles and titanium dioxide effectively preserved the quality of grapes, particularly at 4°C, where superior results were observed over the 28 days. This study demonstrates the integration of MAP and films containing nanoparticles to address the limitations of conventional grape storage methods. This approach offers practical solutions for the horticultural industry and contributes to the advancement of storage and preservation technologies.

Abstract The presence of heavy metals in water, soil, and agricultural products is considered a significant threat to human health. This study aimed to evaluate different heavy metals such as Mercury (Hg), Lead (Pb), Arsenic (As), Cadmium (Cd), Zinc (Zn) and Cobalt (Co), in some vegetable varieties like cucumber, tomato and eggplant and also in the soil and water resources, in greenhouses around the mega industrial zones vicinity (1-10 Km) and comparing it with a greenhouse located in suburb of Isfahan, Iran. Measurement of heavy metals was carried out using ICP-OES in replicate. Concentrations of heavy metals in soil varied by region and generally following the descending pattern: Co > Pb > As > Hg > Zn > Cd. Heavy metals transfer factor were in the order of Cd > Hg > Zn > Pb > Co > As. According to the results, the mega industrial zones of Isfahan province showed a hazardous situation, and notably, heavy metal levels in the suburban region of Isfahan exceeded the health risk index (HRI). Based on the findings, it is recommended that producers adopt regular monitoring of irrigation and soil quality, apply phytoremediation and organic soil amendments to reduce heavy metal uptake, and select low-accumulating crop varieties in order to minimize health risks and ensure sustainable greenhouse production near industrial zones.

Abstract This study explores the effects of cold plasma (CP) treatment on eco-friendly starch/ZnO (SZ) bio-nanocomposite films, incorporating 3 wt% nano-ZnO (ZnO NPs) and varying CP exposure times (0, 30, 60, 90 s). The results indicate that prolonged CP treatment increases film thickness, viscosity, water solubility, moisture absorption, and surface roughness, while reducing contact angle and moisture content. No significant changes were observed in water vapor permeability, density, or UV-Vis properties. CP treatment enhanced tensile strength, elongation at break, and tensile energy to break, while decreasing lightness and whiteness indices without altering color difference. The study highlights CP as a rapid, eco-friendly method for modifying films, with greater efficacy when applied to aqueous starch solutions, offering potential for industrial-scale applications in packaging materials.

Abstract This study investigates how the traditional processing methods, such as cooking and fermentation, affect the nutritional, anti-nutritional, and mineral composition of the six edible grains, including the three rice varieties (Oryza sativa: Matta, Boiled and Brown rice) and the three millets (foxtail, jowar and pearl millet). The grains were analyzed in their raw, cooked, and fermented forms. The carbohydrates and the protein content were determined along with the anti-nutritional compounds such as the flavonoids, oxalates, phenolics, phytates and the tannins. The mineral concentrations of calcium, potassium, iron, magnesium, manganese, and zinc were determined using Atomic Absorption Spectroscopy. The results showed that cooking significantly reduced carbohydrate content by 85-90% across all grains, while fermentation caused an even greater reduction of up to 95%. Protein levels were grain-specific, and fermentation generally enhanced the protein concentration by 20-50%. Flavonoid content was reduced by 70-90% while phytates, and oxalates were reduced substantially by 60-90% through both treatments due to leaching and thermal degradation, while the phenolic content increased by 25-40%, particularly in the foxtail millet. The tannin levels decreased with cooking by 40-60%, but they increased after the fermentation, likely due to the enzymatic release of the bound compounds. Mineral concentrations were consistently declined in the cooking and fermented forms, yet fermentation improved bioavailability by reducing the anti-nutrients. Overall, the cooking was more effective in lowering the anti-nutritional factors, whereas the fermentation enhanced the protein and improved the accessibility of the essential minerals such as iron and zinc. These findings emphasizes the importance of the traditional household processing methods in enhancing the nutritional quality of rice and millet-based diets, particularly in the regions dependent on cereal staples.

Abstract Enzymatic browning mostly happens in fresh fruits and vegetables and is critical in determining the product's shelf life. A class of enzymes known as polyphenol oxidases are responsible for this color alteration. Polyphenol oxidase is the main enzyme that catalyzes the oxidation of phenolic compounds in the presence of oxygen, forming brown pigment. Therefore, several methods are required to prevent these reactions. Natural ascorbic acid is considered among the highly effective chemicals in stopping this reaction and preventing browning. It is a non-toxic and effective alternative to synthetic chemicals. It is also characterized by having powerful antioxidant and free radical scavenging properties. This review offers a focused and novel contribution to the scientific literature by exclusively investigating AA as an anti-browning agent (ABA), enabling a detailed understanding of its specific mechanisms, efficacy, and practical applications. Unlike broader reviews that cover many inhibitors, this work provides a comparative analysis of the performance of AA in various foods, highlighting its strengths and limitations in different contexts. By integrating research from past years, we highlight different approaches, such as the combination with synergists and integration with edible coatings and packaging. Importantly, we not only describe its optimal conditions and benefits, but also assess its limitations, such as its instability and susceptibility. Finally, the evidence and future directions are organized in a way that helps food technologists identify promising protocols, design preservation strategies, and avoid previously documented limitations of future research.