Journal of Food Process Engineering最新文献

This work investigated the coupling of microfiltration (MF) and nanofiltration (NF) to concentrate the volatile compounds in a raspberry hydroalcoholic extract. Enzymatic treatment increased the MF permeate flux by 30%–50%. The highest MF permeate flux was above 50 kg·h⁻¹·m⁻² at a mass reduction ratio of 5. MF allowed efficient clarification of the extract without significant retention of aroma compounds. Among the NF membranes tested using the MF permeate as feed, one membrane was clearly more effective in concentrating the extract in terms of flux (19 kg·h⁻¹·m⁻² at 35 bar), retention of aroma compounds (average retention of 85%), phenolic compounds (61%) and dry matter (90%). Three other membranes were of interest for the fractionation of volatiles in both permeate and retentate but with a lower permeate flux. Finally, one membrane retained few aroma compounds but showed 70% dry matter retention, making it a promising method for aroma purification versus dry matter content in the permeate.

Practical Applications

In this study, we investigated the coupling of crossflow MF and NF with a pectinolytic pretreatment, in order to concentrate the aroma compounds from a raw organic raspberry extract. The aim was to avoid aroma degradation and reduce the operating costs, compared to the conventional concentration thermal technologies. Few authors have studied aroma concentration by NF, which presents an interesting area of research for industrial applications. This work provides keys for flavor manufacturers to add value to their products at a low cost and with limited environmental impact, producing concentrated natural aroma extracts for food. Another originality of this work for industrial companies was to show that thanks to the same process, several fractionations could be achieved simply by modifying the operating conditions. Therefore, this work contributed to propose new applicable processing for the production of natural flavors in a context of high consumer and market demand for organic ingredients.

The objective of this study is to derive the thermodynamic characteristics from sorption isotherm data for canola. The semi-gravimetric method was utilized at three different temperatures (25, 40, and 55°C) and seven air relative humidity levels within the range of 11%–90%. The observed data indicated that the equilibrium moisture content of the sample decreased as the temperature increased. The “GAB and BET” models were applied to fit the empirical data, which demonstrated a Type III isotherm, and the monolayer water content was subsequently determined using these models. Thermodynamic properties such as “isosteric heat,” “net isosteric heat,” “differential entropy,” “net integral entropy,” and “net integral enthalpy” were determined from isothermal sorption curves. The results show that as moisture content increases, both the sorption isosteric heat and the differential entropy of sorption decrease. This indicates that at higher moisture levels, the energy required for additional moisture adsorption and the changes in entropy are reduced. Similarly, the net isosteric heat of sorption and the net integral enthalpy of sorption also decrease with increasing moisture content, consistent with the observed reductions in isosteric heat and differential entropy. The specific absorption surface area for each temperature was determined by calculating the monolayer moisture content using both the “GAB and BET models.” The net integral entropy had an increasing trend in the range of 4%–4.5% (db%), while it decreased in the range of 4.5%–6.8% of moisture content. In addition, the spreading pressure at three levels of temperature was reported. Finally, an empirical relation was employed to illustrate the cumulative energy requirement for drying versus moisture content. The results indicated that at low moisture content levels, the drying process required significantly higher energy.

Practical applications

Moisture sorption isotherms are essential for understanding the interaction between water and food ingredients. This knowledge is vital for improving food processing methods such as drying, mixing, cooling, and storage. In industry, isotherms can help determine the best drying method to maintain food quality, identify the optimal mixing conditions to ensure consistency, establish cooling protocols to prevent spoilage, and set storage guidelines to extend shelf life. In addition, understanding thermodynamic properties is crucial for regulating moisture absorption and release, achieving the desired food texture, managing surface characteristics, and calculating the energy needed for effective dehydration processes.

Eugenia uniflora is a tropical species rich in bioactive compounds that are highly sensitive to processing conditions, particularly those involving heat. Drying is a widely used method for preserving fruit pulp which can affect the stability of these bioactive compounds. The aim of this study was to assess the impact of drying at different temperatures on the retention of phenolic compounds and carotenoids present in the pulp of E. uniflora, with the goal of optimizing the drying process to preserve the pulp's quality. The E. uniflora pulp was dried in an oven with air circulation at three temperatures (45, 65, and 85°C). During the drying process, the moisture content and concentration of phenolics, β-carotene, and lycopene were measured over time. After 260 min of drying, phenolic compounds decreased by 63.97% (45 and 65°C) and by 59.62% (85°C). Carotenoids losses were even more pronounced exceeding 89%, for all temperatures, with β-carotene reductions of 92.91%, 90.72%, and 91.11%, at 45, 65, and 85°C, respectively. Several well-established drying models were tested to represent the moisture content over time. Two models exhibited a high adherence to the experimental data. Zero-order, first-order, and second-order degradation models were used to describe the concentrations of phenolic compounds and carotenoids. For total carotenoids, the model that showed the best results was temperature-dependent. The first-order model provided the best fit for β-carotene and lycopene, with high R² values of 0.9852 (45°C), 0.9776 (65°C), and 0.9681(85°C) for β-carotene, and 0.9776 (45°C), 0.9715 (65°C), and 0.9659 (85°C) for lycopene. These results indicate that higher temperatures accelerate the degradation of bioactive compounds, following a predictable dynamic that can be optimized through adjustments to the drying process.

Practical applications

The fruit of Eugenia uniflora contains phenolic and carotenoid compounds with significant nutraceutical potential. However, the production of this fruit is seasonal, necessitating effective preservation methods. Drying, which involves the removal of water from the pulp, is a common procedure aimed at extending the fruit's conservation and shelf life. Despite its benefits, the drying process poses a challenge, as bioactive compounds like phenolic and carotenoids are sensitive to thermal processing. Their degradation during drying can lead to a reduction in the fruit's bioactive potential. Therefore, it is crucial to understand the kinetics of drying and the degradation of these bioactive compounds to optimize the drying process and maximize the fruit's nutraceutical value.

This study evaluated the efficacy of cooking processes in natural and forced convection systems, for ensuring microbiological safety in industrial-scale ham production. The cold point of the tanks was determined by measuring the water temperature every 2 min, with a maximum variation of 1.4°C between different regions of the tanks. The calculation of the lethal value (F_cal) was carried out using Enterococcus faecalis as the target microorganism due to its high resistance to heat treatment. The cooking temperature was measured at the geometric center of the ham and, in both convection systems, it reached the Fref value (23.6 min), necessary to achieve a reduction of 8 log (8 D), with F_cal of 45.7 and 45 min of cooking in the natural and forced convection systems. Both convection systems achieved microbial reductions exceeding 15-log cycles (15 D), surpassing regulatory requirements despite occasional core temperatures below standard thresholds. In both systems (natural and forced), the cold spot was found on the left side, at a lower height, and toward the front of the tank. After heat treatment, no microorganisms were detected in the ham cooked in natural or forced convection systems. Both systems (natural and forced convection) proved viable at an industrial scale, provided that appropriate cooking protocols are followed.

Practical Applications

The practical applications of this study are significant for the food industry and regulatory bodies involved in food safety. These include quality assurance in ham production, food safety compliance, process optimization, risk mitigation, and guidance for industrial practices. Overall, this study has practical implications for improving food safety, quality control, and production efficiency in the ham industry. It fills a gap in validation studies on industrial-scale ham cooking, providing valuable information for industry stakeholders and regulatory bodies alike.

The process of deep-frying brings about significant physicochemical changes in the color and moisture content of foods, influenced by heat and mass transfer phenomena. Achieving consistent quality in fried foods, such as nuggets, fries, and chicken pies, is challenging, highlighting the importance of predicting these changes. This study delves into the evolving dynamics of color and moisture content, specifically in French fries during deep frying. To model these changes, the study employs a first-order kinetic equation for color and moisture content, utilizing numerical solutions like the Runge–Kutta fourth-order method as well as the Nelder–Mead algorithm in MATLAB. The Arrhenius equation plays a key role in this model. The modified model is compared against an existing model using the root mean square error (RMSE) and Akaike information criterion (AIC). Note that the investigation evaluates how oil temperature (at 150, 170, and 190°C) as well as sample thickness (at 5, 10, and 15 mm) impact the French fries' moisture and color content during frying. Results indicate that the modified model, with its improved accuracy and lower RMSE and AIC values compared to the existing model, provides a more reliable tool for understanding the frying process. Consequently, the inclusion of a user-friendly graphical interface (GUI) makes this modeling approach accessible even to those with limited mathematical or programming expertise, benefiting professionals seeking more profound insights into the frying process.

Practical applications

The graphical user interface (GUI) for predicting deep-fried food quality presented in this study holds broad industrial applications. It serves as a pivotal tool in the food industry for ensuring consistent quality across products like fries and nuggets, enabling manufacturers to optimize frying processes. Fast-food chains can use the GUI to minimize costs and energy consumption while maintaining product quality. In addition, it aids in equipment calibration, becoming an invaluable asset for operators seeking optimal performance and longevity in deep-frying equipment. Culinary schools benefit from this GUI as an educational tool, offering aspiring chefs a practical understanding of deep-frying science. Researchers and food scientists can accelerate R&D cycles by efficiently assessing the impact of variables. SMEs, regulatory bodies, and food retailers find utility in the GUI for quality control, compliance, and consumer education, collectively contributing to industry transparency, sustainability, and improved global health outcomes.

Thermal and mechanical treatments may affect the structure of hydrolyzed proteins, thus influencing the obtaining of peptides with improved bioactivity. In this work, tilapia muscle was treated by thermal sterilization or homogenization with ultra-turrax (UT) and hydrolyzed with alcalase to obtain FPHs with antioxidant properties in salad dressing. To evaluate the bioactive potential of FPHs, the acetylcholinesterase inhibition assay was applied, resulting in up to 45.87% inhibition for the UT sample (60 mg/mL). Also, no cytotoxicity was detected by Allium cepa model for all FPHs. The emulsifying activity index and emulsifying stability index of FPHs indicated better emulsifying capacity in basic pH. As a proof of concept, FPHs were used as an emulsifying/antioxidant agent to prepare a salad dressing. FPHs increased the formulation's protein content, pseudoplastic behavior, color, and texture. In addition, FPHs aided the oxidative stability of salad dressing (evaluated by oil's extinction coefficient), demonstrating potential application in emulsified foods by acting on the elimination of radicals generated in lipid oxidation.

Practical applications

Fish protein hydrolysates (FPHs) offer diverse bioactive properties such as antioxidant, antimicrobial, anticancer, antihypertensive, and acetylcholinesterase (associated with Alzheimer's disease) inhibitory effects. However, optimizing their technological properties poses a challenge, affecting applicability and bioactivity. Industrial processes such as thermal and mechanical treatments can alter protein structures, influencing peptide bioactivity post enzymatic hydrolysis. This study investigates the impact of substrate pre-treatments, sterilization via thermal heating, and homogenization using a rotor-stator system (ultra-turrax) on FPHs' technological properties after hydrolysis with alcalase, including emulsifying capacity and acetylcholinesterase inhibitory capacity. In addition, it explores the application of pre-treated FPHs in a real food system (French salad dressing), assessing rheological properties, texture, and oxidative stability. Such evaluations are crucial for ensuring the feasibility of industrial FPHs production and their application.