Journal of Food Process Engineering最新文献

Ensuring efficient grading of guavas is crucial for timely postharvest storage and maximizing profits. Currently, the subjective nature of manual grading underscores the need for more sophisticated methodologies. However, employing machine vision for intelligent grading faces hurdles due to the diverse characteristics of guavas and the high development costs. This research targets the limitations in the guava grading process and introduces an intelligent system to overcome them. The system's structure and operational procedures were outlined, establishing diverse standards encompassing guava color, shape, size, and integrity. Image capture and preprocessing of guavas are completed. Employing the RGB model, the study performed color feature extraction and guava recognition, alongside diameter and integrity assessment through edge detection. Following a thorough analysis of various models, ResNet50 emerged as the preferred choice for guava image evaluation and depth recognition. Subsequently, an intelligent guava grading system was developed using Microsoft Visual Studio 2017. Experimental results demonstrated outstanding grading accuracy of 98.05%, with grading speed averaging 5.47 times faster than manual methods. Compared to traditional manual grading techniques, the system excelled in work efficiency, speed, reliability, and robustness.

Using variable temperature and relative humidity of natural air based on local climatic conditions for natural drying aeration of grain is an energy-saving and efficient method. The study of heat and moisture transfer within grain piles during natural air and low-temperature air drying aeration of bulk corn in low-humidity areas, which can provide theoretical support for selecting efficient and low-consumption grain drying processes and practical applications. In this study, the mathematical model of the coupled heat and moisture transfer dynamics in the dry silo was verified using experimental datum of grain storage drying aeration experiment, and the relative error was less than 5% between the simulated and the experimental datum. Based on this validated model, the temperature and moisture content variations of in-silo bulk corn drying were simulated by computational fluid dynamics (CFD) numerical simulation techniques. The simulations included continuous drying aeration with daily average, hourly average temperature and relative humidity of the local natural air, and low-temperature air drying aeration with heated up to 3°C over the ambient temperature, as well as intermittent drying aeration. Drying effectiveness and economic efficiency were also analyzed and evaluated. The costs for continuous drying aeration with hourly average of natural air and low-temperature, intermittent drying aeration with hourly average of natural air are 0.032, 0.042, and 0.016 CNY/kg, respectively. Compared to traditional high-temperature hot air drying, the costs of these methods were reduced by 0.048, 0.038, and 0.064 CNY/kg, respectively.

Turmeric is a medicinal herb that can be used in a wide range of applications, such as food ingredients, cosmetics, and traditional medicine. The active ingredients found in turmeric are curcumin (CUR), desmethoxycurcumin (DMC), and bisdesmethoxycurcumin (BMDC). The aim of this research was to precipitate the active ingredients from a turmeric extract using the gas anti-solvent process with carbon dioxide as the anti-solvent. The effects of solvent type (ethanol, methanol, and acetonitrile), precipitation temperature (25°C–45°C), and CO₂ flow rate (4–12 mL/min) on the amount of precipitates were investigated using the Box–Behnken design of experiments. The precipitates were analyzed for curcuminoids and CUR content using HPLC and were tested for antioxidant activity. It was found that solvent type and temperature were significant variables at a 5% significance level on the amount of precipitates. Using a mixture of ethanol and methanol (77.5% v/v ethanol) with a polarity index of 4.48 as the solvent, a precipitation temperature of 25.40°C, and a CO₂ flow rate of 7.56 mL/min was found to be the optimal conditions for achieving the highest amount of precipitates. At the optimal conditions, the amounts of curcuminoids and CUR precipitates were found to be 27.33 ± 0.23 and 13.30 ± 0.12 mg/5 mL of extracted solution, respectively. In the antioxidant studies, the Trolox equivalents found in the products at the optimal conditions using DPPH and ABTS assays were 38.19 ± 0.17 and 65.96 ± 2.36 mg/5 mL of extracted solution, respectively. The total phenolic content was found to be 30.84 ± 1.80 mg/5 mL of extracted solution.

The research aimed to study how different drying methods (spray and freeze drying) affect the release kinetics of microencapsulated astaxanthin in various environmental conditions. Shrimp shell extract containing astaxanthin was encapsulated using different wall components (maltodextrin with different dextrose equivalents and modified starch) via a simplex lattice mixture design. The encapsulated extract was then subjected to storage at different temperatures (25°C ± 2°C and 2°C ± 4°C) and humidity conditions (52% ± 2% and 75% ± 2%), as well as exposure to UV light (four 15 W lamps, 254 nm, for 10 h). The release kinetics of astaxanthin were analyzed using various models (page, Newton Korsmeyer–Peppas model, Modified Henderson and Pabis, Diffusion approach, and Two-term exponential). The evaluation results of correlation coefficient (R²), root mean square deviation (RMSE), and mean absolute percentage error (MAPE) values of different models showed that the astaxanthin degradation followed a two-term exponential kinetics in both types of microcapsules. Astaxanthin degradation increased with higher temperatures, humidity, and UV light exposure. However, microcapsules with equal wall compound ratios exhibited better preservation of astaxanthin. The study also emphasized the significance of optimizing storage conditions and wall materials for microencapsulated astaxanthin, as well as the utility of the two-term exponential model in enhancing stability and shelf life.

The sucupira fruit (Pterodon pubescens) contains a valuable oil characterized by high levels of fatty acids and an abundance of bioactive compounds, such as flavonoids and terpenoids. This study aimed to evaluate the use of ultrasound-assisted extraction to obtain sucupira fruit oil through a complete 2² factorial rotational design. The effects of ultrasound intensity (%) and ethanol concentration (%) on lipid content, antioxidant capacity, color, and reducing capacity were assessed. The maximum lipid content was 26.9/100 g, which was significantly higher than that obtained by the Soxhlet method (23.4/100 g). The extract obtained at the optimized conditions (90% ultrasound intensity and 80% ethanol concentration) showed antimicrobial activity against Salmonella and Escherichia coli cocktails. Compounds such as β-caryophyllene, caryophyllene oxide, α-humulene, α-copaene, and spathulenol, responsible for biologically relevant activities, were identified in the extract through GC/GC–MS. HPLC–MS/MS identified compounds such as catechin, luteolin, quercetin, taxifolin, among others.