Mathematical modeling of nutritional, color, texture, and microbial activity changes in fruit and vegetables during drying: A critical review

Thermoanalytical study of protein state during rehydration and rehydration kinetics in osmotically dehydrated pork meat (Longissimus dorsi): Insights from Peleg and Weibull models

Osmotically dehydrated pork meat (Longissimus dorsi), in the molasses, was used in the aim to study the protein state during rehydration. Protein state and rehydration kinetics are crucial for obtaining the desired meat product quality. The thermoanalytical techniques were employed to follow protein state and kinetics of rehydration. Obtained kinetic parameters were Peleg's rate constant (k1), 34.43, 6.23, and 10.15 (min (kg d.m.)(kg water)-1) and Peleg's capacity constant (k2), 0.726, 1.243, and 0.860 at 20, 30, and 40 °C, respectively. Parameters of Weibull's model, α, β (min), at 20 °C were 34.4; 0.86, at 30 °C were 6.24; 1.24, at 40 °C were 10.15; 0.86. From obtained enthalpies (ΔHd) and temperatures (Td) of meat proteins denaturation, it was found that proteins were partly denatured and gradually lost their structure and thermal stability during rehydration. Rehydration kinetic parameters indicated that most efficient rehydration was found to be at the 40 °C.

Enhancing drying characteristics and quality of fruits and vegetables using biochemical drying improvers: A comprehensive review

Traditional drying is a highly energy-intensive process, accounting for approximately 15% of total manufacturing cost, it often resulting in reduced product quality due to low drying efficiency. Biological and chemical agents, referred to as biochemical drying improvers, are employed as pretreatments to enhance both drying characteristics and quality attributes of fruits and vegetables. This article provides a thorough examination of various biochemical drying improvers (including enzymes, microorganisms, edible film coatings, ethanol, organic acids, hyperosmotic solutions, ethyl oleate alkaline solutions, sulfites, cold plasma, carbon dioxide, ozone, inorganic alkaline agents, and inorganic salts) and their effects on improving the drying processes of fruits and vegetables. Additionally, it introduces physical drying improvers (including ultrasonic, pulsed electric field, vacuum, and others) to enhance the effects of biochemical drying improvers. Pretreatment with biochemical agents not only significantly enhances drying characteristics but also preserves or enhances the color, texture, and bioactive compound content of the dried products. Meanwhile, physical drying improvers reduce moisture diffusion resistance through physical modifications of the food materials, thus complementing biochemical drying improvers. This integrated approach mitigates the energy consumption and quality degradation typically associated with traditional drying methods. Overall, this review examines the role of biochemical agents in enhancing the drying characteristics and quality of fruits and vegetables, offering a comprehensive strategy for energy conservation and quality improvement.

Enhancing physicochemical, bioactive, and nutritional properties of sweet potatoes: Ultrasonic contact drying with slot jet nozzles compared to hot-air drying and freeze drying

Sweet potatoes are a rich source of nutrients and bioactive compounds, but their quality can be impacted by the drying process. This study investigates the impact of slot jet reattachment (SJR) nozzle and ultrasound (US) combined drying (SJR + US) on sweet potato quality, compared to freeze-drying (FD), SJR drying, and hot air drying (HAD). SJR + US drying at 50 °C closely resembled FD in enhancing quality attributes and outperformed HAD and SJR in key areas such as rehydration, shrinkage ratios, and nutritional composition. Notably, SJR + US at 50 °C produced the highest total starch (36.84 g/100 g), total dietary fiber (8.48 g/100 g), total phenolic content (158.19 mg GAE/100 g), total flavonoid content (119.08 mg QE/g), DPPH antioxidant activity (6.44 μmol TE/g), β-carotene (31.98 mg/100 g), and vitamin C (5.27 mg/100 g). It also exhibited higher glass transition temperatures (Tg: 14.49 °C), indicating better stability at room temperature. The hardness values for SJR + US samples were similar to FD, while HAD samples had the highest hardness. SJR + US at 50 °C resulted in the lowest total color changes (ΔE), indicating minimal impact on appearance. Additionally, FTIR analysis revealed that peaks in specific spectral regions indicated superior preservation of bioactive compounds in SJR + US samples compared to other methods, which was also confirmed by principal component analysis (PCA) and heatmap visualization. Overall, these findings suggest that SJR + US is an effective alternative to conventional drying techniques, significantly improving the quality of dried sweet potatoes.

Multiphysical field and multiobjective mathematical modeling of grain-oilseed storage: Current status and future trends

Storage is an important process involved in the postharvest treatment of grain-oilseed and is necessary for maintaining high quality and ensuring the long-term supply of these commodities in the food industry. Proper storage practices help prevent spoilage, maintain nutritional value, and preserve marketable quality. It is of great interest for storage to investigate flow, heat and mass transfer processes, and quality change for optimizing the operation parameters and ensuring the quality of grain-oilseed. This review discusses the mathematical models developed and applied to describe the physical field, biological field, and quality change during the storage of grain-oilseed. The advantages, drawbacks, and industrial relevance of the existing mathematical models were also critically evaluated, and an organic system was constructed by correlating them. Finally, the future research trends of the mathematical models toward the development of multifield coupling models based on biological fields to control quality were presented to provide a reference for further directions on the application of numerical simulations in this area. Meanwhile, artificial intelligence (AI) can greatly enhance our understanding of the coupling relationships within grain-oilseed storage. AI's strengths in both qualitative and quantitative analysis, as well as its effectiveness, make it an invaluable tool for this purpose.

A study into how thickness, infrared intensity, and airflow affect drying kinetics, modeling, activation energy, and quality attributes of apple slices using infrared dryer

Drying is a widely recognized process that reduces the need for storage and shipping weight, keeps free water out of the product, and prolongs its shelf life. An infrared dryer was designed to dry apples under different drying conditions. Apple slices of 6-, 4-, and 2-mm thicknesses were dried at intensities 0.130, 0.225, and 0.341 W/cm2 and airflow 1.0, 0.5, and 1.5 m/s. The dehydrating period was prolonged with higher airflow and shortened with higher infrared intensity (IR). The shortest dehydrating period was verified by 190 min at 0.341 W/cm2, 0.5 m/s under 2 mm thickness. Increasing the sample thickness from 2 to 4 mm and then to 6 mm resulted in an 84% and 192% increase in drying time, respectively. Dehydrated apples had water activity values ranging from 0.30 to 0.40. The shrinkage ratio increased with an increase in infrared radiation intensity. However, it decreased with an increase in air velocity, while the rehydration ratio decreased with an increase in radiation intensity and increased with an increase in air velocity. Regarding total color change, apple slice thickness was a major factor. The effective diffusivities varied between 2.6 and 9.0 𝗑10-10 m2/s under different drying conditions. The dehydrating curves of apples were best described by the model developed by Midilli et al.

Mathematical modeling of thin-layer drying kinetics and moisture diffusivity study of apple slices using infrared conveyor-belt dryer

The drying features of apples at different infrared drying settings were investigated. The drying time, moisture-effective diffusion, and activation energy of infrared dried apples were measured experimentally and statistically as a function of slice thicknesses, radiation intensity, and air velocity. The infrared intensity of 0.225, 0.130, and 0.341 W/cm2 , slice thicknesses of 6, 4, and 2 mm, and airflow of 0.5, 1.0, and 1.5 m/s were used to dry apple slices. The data shows that the drying time reduced as IR increased, but airflow and slice thickness increased. Eight statistical factors were used to compare 11 alternative mathematical drying models. The experimentally acquired drying curves were matched to the thin-layer drying equations. According to the calculations, the Midilli et al. equation had the greatest (efficiency and R2 ) and lowest (χ2 , sum of squared errors, standard error of estimate, standard error, standard deviation of difference) values. As a result, this equation is the best for modeling the drying curves of apple slices across all drying circumstances. The optimum moisture diffusivity value varied from 2.59 to 9.07 × 10-10  m2 /s. The mean activation energy was determined to be 19.02-29.83 kJ/mol under various experimental conditions.

Consumer-oriented smart dynamic detection of fresh food quality: recent advances and future prospects

Since fresh foods include a significant amount of water, fat, and protein, it is more likely to become infected by microorganisms causing a major loss of quality. Traditional detection techniques are less able to meet customer expectations owing to the limitations of high cost, slow response time, and inability to permit dynamic monitoring. Intelligent non-destructive detection technologies have emerged in recent years, which offer the advantages of small size and fast response at low cost. However, dynamic monitoring of fresh food quality based on intelligent detection technologies on the consumer side has not been rigorously evaluated yet. This paper discussed the application of intelligent detection technologies based on the consumer side in the dynamic monitoring of fresh food freshness, microorganisms, food additives, and pesticide residues. Furthermore, the application of intelligent detection technologies combined with smartphones for quality monitoring and detection of fresh foods is evaluated. Moreover, the challenges and development trends of intelligent fresh food quality detection technologies are also discussed. Intelligent detection technologies based on the consumer side are designed to detect in real-time the quality of fresh food through visual color changes in combination with smartphones. This paper provides ideas and recommendations for the application of intelligent detection technologies based on the consumer side in food quality detection/monitoring and future research trends.

Individual and interactive effect of ultrasound pre-treatment on drying kinetics and biochemical qualities of food: A critical review

One of the earliest and most prevalent processing methods to increase the shelf-life of foods is drying. In recent years, there has been an increased demand to improve product quality while lowering processing times, expenses, and energy usage in the drying process. Pre-treatments are therefore effectively used before drying to enhance heat and mass transfer, increase drying efficiency, and lessen degradation of final product quality. When food is dried, changes are expected in its taste, color, texture, and physical, chemical, and microbial properties. This has led to the need for research and development into the creation of new and effective pre-treatment technologies including high-pressure processing, pulsed electric field, ultraviolet irradiation, and ultrasound. Sound waves that have a frequency >20 kHz, which is above the upper limit of the audible frequency range, are referred to as "ultrasound". Ultrasonication (US) is a non-thermal technology, that has mechanical, cavitational, and sponge effects on food materials. Ultrasound pre-treatment enhances the drying characteristics by producing microchannels in the food tissue, facilitating internal moisture diffusion in the finished product, and lowering the barrier to water migration. The goal of ultrasound pre-treatment is to save processing time, conserve energy, and enhance the quality, safety, and shelf-life of food products. This study presents a comprehensive overview of the fundamentals of ultrasound, its mechanism, and how the individual effects of ultrasonic pre-treatment and the interactive effects of ultrasound-assisted technologies affect the drying kinetics, bioactive components, color, textural, and sensory qualities of food. The difficulties that can arise when using ultrasound technology as a drying pretreatment approach, such as inadequate management of heat, the employment of ultrasound at a limited frequency, and the generation of free radicals, have also been explained.