The particle-fluid convective heat transfer coefficient (h fp) is a critical parameter in cooking processes, determining heat and mass transfer rates between food particles and heating media, which has a significant impact on the final food quality. In this study, pork loin was used as the test sample. The particle-fluid relative velocity was measured and a linear relationship was established between control conditions and particle-fluid relative velocity during boiling, steaming, and stir-frying processes. The h fp was determined by a hypothetical trial algorithm, which revealed its relationship with the cooking operating conditions. Additionally, the dimensional analysis method was employed to construct h fp dimensionless models during cooking processes. Our results demonstrated the existence of a linear relationship between the heating power during boiling and steaming, the stirring speed during stir-frying, and the particle-fluid relative velocity (Equations 11-13). The h fp values for boiling, steaming, and stir-frying ranged from 544 to 1321, 211 to 404, and 410 to 1706 W/m2K, respectively. The h fp was influenced by various factors, including particle size, the particle-fluid relative velocity, medium temperature, and thermophysical properties of the heat transfer medium. Specifically, smaller pork loin feature size, higher heating power during boiling and steaming, faster stirring speed, and higher oil temperature during stir-frying resulted in a greater h fp. We constructed h fp dimensionless models during boiling, steaming, and stir-frying based on dimensional analysis, where h fp was expressed as a function of the Nusselt number (Nu). The validation experiments showed that the average relative errors of h fp dimensionless models for boiling, steaming, and stir-frying processes are 0.82%, 0.90%, and 1.89%, respectively, which confirmed the accuracy and reliability of h fp dimensionless models.

Although starching technology is widely used, fundamental research on how it enhances food quality by regulating heat transfer mechanisms remains limited. To fills this gap, this study employed pork tenderloin to simulate stir-frying conditions, systematically investigating the effects of different starch concentrations (2%, 6%, 10%) and oil temperatures (80-140 degrees C) on the heat transfer process. By integrating bubble behavior, heat balance calculation, and quality evaluation, the mechanism by which starching influences heat transfer during thermal processing and its impact on quality formation was elucidated. The results showed that starching increased the heating rate by up to 29% and raised the surface heat transfer coefficient between frying oil and particle (hfp) by up to 1.5 times. Starching also significantly altered interfacial bubble behavior: the bubble count increased by up to 4 times, while the average diameter decreased by 40%. This enhancement is attributed to the ability of the starching to retain and regulate water evaporation during heating, thereby promoting the nucleation and movement of denser and smaller bubbles at the oil-solid interface, which effectively enhances interfacial turbulence and heat transfer. Heat balance analysis further confirmed that the heat increase resulting from the elevated hfp exceeded the additional heat consumption due to water evaporation from the starching, thereby accelerating the overall heating process. These improvements in heat transfer directly translated into significant quality enhancements: starching samples exhibited a 1.3%-2.0% increase in moisture retention, an 36.9%- 45.2% reduction in shear force, and a 10.8%-11.9% improvement in VB1 retention. This study reveals the physical mechanism by which starching improves cooking quality from a heat transfer perspective, providing a theoretical basis for optimizing starching processes in the food industry to enhance product texture and nutrient retention.

Excessive lipid consumption poses a dual challenge to public health and the sustainability of global agri-food systems. Cooking processes represent a critical intervention point for simultaneously improving dietary quality and enhancing resource-use efficiency. This study investigated the oil adsorption mechanism in stir-fried pork tenderloin and proposes a resource-efficient culinary protocol using "Maturity Value" (M) as a standardization metric. Results indicated a positive correlation between pork tenderloin's total oil content and cooking doneness within the 100–180 °C range, while moisture content showed an inverse trend. Optimization experiments revealed that stir-frying at 140 °C with a terminal maturity of M = 0.5 min exhibited the lowest total oil content (6.39

Sterilization is essential for achieving the safety, shelf life, and quality of spicy chicken retort pouches (SCRPs). However, the irregular and geometrically complex shapes of chicken pieces lead to variable cold spot locations, complicating optimization of batch sterilization. To address this challenge, a 3D simulation-based approach was adopted to develop a transient heat transfer model for irregularly shaped SCRPs, and a novel geometry-control method was introduced to standardize product shape, enabling the construction of a corresponding model for regularly shaped SCRPs. Both models were validated, showing high accuracy with coefficients of determination (R-2 > 0.981) and low mean relative errors (sigma < 2.997 %) between experimental and simulated temperature profiles. The regularly shaped SCRP model was then applied to process optimization, identifying an optimal thickness of 20 mm and a variable retort temperature (VRT) profile of 95 degrees C for 25 min followed by 121 degrees C for 15 min. This schedule achieved an F value of 6.58, reduced the surface cook value (Cs) and the volume-average cook value (C-avg) by 42.95 % and 42.05 %, respectively, and shortened sterilization time by 26.07 %. Furthermore, the optimized process improved product quality by lowering shear force, moisture loss, and oil viscosity, while enhancing color retention and sensory acceptance. These findings confirm the reliability of the developed models and their potential to guide industrial batch sterilization design.

This research concentrated on soybean paste fermented with Tetragenococcus halophilus, employing peptidomics and machine learning methodologies to screen for novel umami peptides. Taste characteristics of umami peptides were evaluated through sensory evaluation and electronic tongue analysis. The mechanism of taste presentation of the umami peptides was investigated through T1R1/T1R3 molecular docking techniques. Four peptides were identified: LLYGKVVKKT, DKKVSVGT, TRKQALLN, and QKNSHQ, with umami thresholds ranging from 0.02 to 0.14 mmol/L. Hydrogen bonds and electrostatic interactions are the key forces between umami peptides and receptors, and the length of hydrogen bonds is between 2.94 and 3.30 Å. Molecular docking analyses revealed that electrostatic and hydrogen bonding interactions are crucial, with ARG 248 and ALA 282 serving as key binding sites on T1R1 and T1R3 receptors, significantly influencing umami intensity. These findings aid in further understanding the flavor properties of umami peptides in soybean paste.

[Objective] In order to explore the loss pattern of VC in kiwifruit pork jerky by twin-screw extrusion and solve the "black box" problem of nutrient loss during the extrusion process. [Methods] In this paper, a twin-screw extruder was used to produce kiwifruit pork jerky, and the VC content of the material before and after extrusion was determined by high performance liquid chromatography, and the Mean Residence Time （MRT） was used as the reaction time of the material in the barrel, and the VC loss rate under different extrusion conditions was dynamically analyzed. [Results] Increasing the temperature and moisture content of the barrel, decreasing the screw speed, and increasing the amount of dried fruit added during the extrusion process will increase the VC loss rate of the extruded material. The variation pattern of MRT and VC loss rate is basically consistent. Dynamic analysis shows that VC loss during the extrusion process follows a first-order dynamic model, and the VC loss rate constant is between 0.003 54 and 0.006 05 s-1. [Conclusion] MRT is an important factor affecting the variation of VC loss rate. A predictive model for VC loss rate can be obtained through multiple regression analysis, which can achieve reasonable prediction of the variation pattern of VC loss rate under different conditions and reduce production costs.

Abstract Chinese cooking is the primary treatment method for table food in China. The process is complex and large‐scale, which is important to the macroeconomy and national nutrition and health. First, this article puts forward the concept of thermal accumulation for Chinese cooking by taking pork tenderloin fried at different oil temperatures, explaining changes in moisture content, hardness, and color with different thermal accumulation conditions, and measuring kinetic parameters. The variations of L* and b* obtained by the experimental results belong to the first‐order reaction kinetic model, while the changes in water content and shear force belong to the zero‐order reaction kinetic model. Simultaneously, the superheat value is used as a thermal accumulation indicator, combined with sensory evaluation to determine that the Z value of the human sensory overheating of pork tenderloin is 99°C, and Os,max (Z = 99°C, the reference temperature is 110°C) is 5.86 min.

The World Health Organization (WHO) has identified the use of iron cookware as a potential strategy for alleviating iron deficiency anaemia (IDA) and emphasises the need for action-oriented research in this area. In response to this need, our study systematically investigated the patterns of iron release from various types of cookware under different cooking conditions. Among these, nitrided iron pots (NIPs), the most widely used cookware, were selected for the development of kinetic models to predict iron release efficiently across a range of cooking temperatures and pH levels in food materials. Our results demonstrated that iron release from the pots was significantly influenced by cooking conditions such as the type of cookware, cooking temperatures, cooking times, types of acidic substances, and the pH of the cooking environment. Specifically, higher temperatures, longer cooking times, lower pH levels, and the presence of acetic acid were found to maximise iron release into food. We developed a series of kinetic models—Iron Release-Temperature Models (I, II, and III) and Iron Release-pH Models (IV, V, and VI)—to predict iron release from NIPs. The temperature models are applicable for cooking food with a pH of 5.00–6.00 within a temperature range of 50–100°C, while the pH models are designed for food with a pH of 3.00–6.00 at boiling temperatures. Validation experiments confirmed the relative accuracy of these models. Additionally, when comparing the predicted iron release with the Recommended Nutrient Intake (RNI) guidelines, the findings support the efficacy of iron pots as a viable method for iron supplementation.

In order to investigate the law of heat transfer change of steaming and the influence of heat transfer process on the change of food quality,by measuring the distribution law of heat transfer coefficient between gas and solid during steaming,combined with the theory of Termination Maturity value,the Termination Maturity value of different food products were used as sampling benchmarks to obtain the quality change of food products steamed and ripened under different surface heat transfer coefficients and then carried out heat treatment kinetic analysis.The results showed that:the heat transfer coefficient between gas and solid at 1/2 of the radius of the steaming grid in the steamer were the highest （290～2 142 W/（m~2·K））,the center of the steaming grid was the second highest （210～1 628 W/（m~2·K））,and the edge of the steaming grid was the lowest（158～1 160 W/（m~2·K））;the moisture content,shear,color of potatoes,steamed buns and Leiocassis longirostris steamed to maturity at different heat transfer coefficient between gas and solid.The quality change indexes follow the first-order kinetic,and the cooking loss follows the zero-order kinetic model;when steamed at a surface heat transfer coefficient of 2 142 W/（m~2·K）,the temperature rise is the fastest,the steaming time is the shortest,the quality loss of each of the three types of food is the lowest,and the steaming energy consumption is the least.Therefore,the steaming conditions with higher surface heat transfer coefficient should be chosen as much as possible for daily and industrial steaming.

Polyhydroxy alcohol-mediated curing has great potential for producing low-salt cured meat products. This study investigated the mass transfer kinetics and the one-way diffusion simulation of sodium chloride (NaCl) during the curing process. Furthermore, Fick’s second law determined the NaCl diffusion coefficient (De) of xylitol-mediated cured pork tenderloin. The results demonstrated that adding xylitol could reduce the De of NaCl. The De of NaCl, calculated using the one-way model, was 1.29 × 10−9 m2·s−1, 1.22 × 10−9 m2·s−1, 1.2 × 10−9 m2·s−1, and 1.15 × 10−9 m2·s−1 when the amount of xylitol added was 0%, 4%, 8%, and 12% (w/w), respectively. This result agrees with the predicted values from the power function time-varying model. Moreover, a three-dimensional simulating model of mass transfers constructed using COMSOL Multiphysics was developed to evaluate the NaCl diffusion in pork tenderloin during the curing process. This model has high accuracy and can be used to describe the diffusion of NaCl in curing. Overall, this study provided a foundation for NaCl diffusion and distribution during the curing process.

The degree of organised alignment of fibre structures, referred to as the degree of orientation, significantly influences the textural properties and consumer acceptance of fibrous foods. To develop a new method to quantitatively characterise the fibre structure of such foods, a laser transmission imaging system is constructed to capture the laser beam spot on a sample, and the resulting image undergoes a series of image processing steps that use computer vision to translate the light and dark variations of the original images into distinct ellipses. The results show that the degree of orientation can be reasonably calculated from the ellipse obtained by fitting the outermost isopixel points. To validate the reliability of the newly developed method, we determine the degree of orientation of typical fibrous foods (extruded beef jerky, pork jerky, chicken jerky, and duck jerky). The ranking of the measured orientation agrees with the results of pseudocolour maps and micrographs, confirming the ability of the method to distinguish different fibrous foods. Furthermore, the relatively small coefficients of variation and the strong positive correlation between the degree of organisation and the degree of orientation confirm the reliability of this newly developed method.

为了探究中式烹饪菜肴在配送过程中的品质变化,本文以猪里脊肉和蒜薹为对象,结合相同成熟值取样技术,对比油炒菜肴在热链配送(保温箱,65℃,0～2 h)和冷链配送(冰箱,4℃,0～48 h)时的品质变化并进行动力学分析.结果表明:配送过程中维生素B1(猪里脊肉)、维生素C(蒜薹)、水分含量、剪切力、颜色品质水平变化遵循一级动力学模型,失重率品质水平遵循零级动力学模型,冷链配送时维生素B1(猪里脊肉)、维生素C(蒜薹)降解的半衰期(t1/2)是热链配送时的98、484倍.维生素B1、维生素C在热链配送过程中的营养品质损失(25.62％～35.42％、43.01％～59.24％)比冷链配送菜肴损失(14.00％～17.89％、14.10％～24.97％)高1倍左右.由此可见,冷链配送能更好地保持菜肴营养价值,也更适合应用于中央厨房、团餐配送等场合.

油炒是我国主要菜肴的烹饪手段,而消费者不希望摄入过多油脂,因此有必要研究影响油炒菜肴油脂含量的因素及机理.影响菜肴油脂含量的参数很多,其中烹饪火候控制是决定油脂含量的前提.为此,选择油炒猪里脊肉为研究对象,以等终点成熟值为研究基准,探索油炒温度、搅拌速度等火候控制手段对油脂含量的影响规律,进而基于传质过程原理构建油-水扩散模型,探索油脂和水分在油炒烹饪过程中的传质规律.结果表明,油炒温度、搅拌速度对猪里脊肉油脂含量都有显著影响(P<0.05).在油炒温度120℃,油炒时间29 s和搅拌速度0.23 m/s下烹饪猪里脊肉油脂含量平均为6.00 g/100 g,而继续加热,其油脂含量可达10.64 g/100 g,与刚成熟相比增加了77.33％,由此说明在最优火候控制下可获得最低的油脂含量.所构建的传质模型中油脂和水分含量模拟值与试验结果符合程度较高.结果显示油炒温度越高,猪里脊肉油脂和水分有效扩散率越大,分别在2.272×10-10～3.713×10-10 m2/s、1.277×10-10～6.343×10-10 m2/s之间,说明传质过程中油脂吸入和水分蒸发并不同步.

Traditional Suantangyu (STY) is made by cooking fish in the fermented sour soup and has a distinctive flavor. To determine the doneness and analyze the flavor and volatile compounds in cooking STY for reasonable manufacturing guidance, the maturity value model, sensory evaluation, E-nose, E-tongue, and HS-SPME-GC-MS were employed in this paper. Results indicated that the maturity state (MyS) and optimal flavor state (OFS) were obtained by cooking STY 1.89 min at 50 degrees C and 15 min at 80 degrees C, respectively. Differences in the flavor of different cooking states of STY were found via principal component analysis (PCA) of E-nose and E-tongue. Moreover, the strongest sourness and saltness and the lowest astringency and bitterness were detected in OFS. Fifty-seven volatiles were identified in STY via HS-SPME-GC-MS. The most abundant volatiles were detected in OFS, particularly alcohols, esters, and aldehydes. Nonanal, octanal, eucalyptol, linalool, and ethyl acetate with high relative odor contribution (ROC) were the key odor-active compounds in STY. This work could offer rational determination of doneness and deeper insight into flavor quality control during STY cooking. Novelty impact statement This work quantitatively determined the cooking doneness of Chinese traditional Suantangyu via integrating sensory evaluation and kinetics. The optimal flavor state of Suantangyu showed stronger aroma and taste attributes than the maturity state via analysis of E-nose, E-tongue, and HS-SPME-GC-MS. Finally, nonanal, octanal, eucalyptol, linalool, and ethyl acetate were the key odor-active compounds in Suantangyu.

Traditional high-salt fermented Suanyu is an ethnic fermented fish product in southwest China. Lactic acid bacteria (LAB) are the most appropriate strains because of their technological properties during ripening fermentation. The diversity of LAB in high-salt fermented Chinese Suanyu was examined through high-throughput sequencing (HTS), and the most suitable LAB strain was acquired through strain isolation and characterization, surimi simulation fermentation system, and principal component analysis (PCA). The processing adaptability of the strain was examined via Suanyu fermentation. Results showed that Lactobacillus, Tetragenococcus, and Weissella were the dominant bacteria in Suanyu, and their contributions were 53.99%, 35.60%, and 4.10%, respectively. The most suitable strain (Lactobacillus plantarum B7) rapidly produced acid, exhibited a strong antibacterial activity, showed salt tolerance, and had no amino acid decarboxylase activity. pH decreased to about 3.6. Eventually, the ability to tolerate 20% salt was observed, and the activity of amino acid decarboxylase was negative. Fermented Suanyu with B7 rapidly produced acid (11.7% d-1). The non-protein nitrogen (NPN) and total free amino acid (FAA) contents of fermented Suanyu were higher and its total volatile base nitrogen (TVB-N), thiobarbituric acid (TBARS), and biogenic amines (BAs) levels were lower than those of naturally fermented Suanyu. Therefore, B7 is a potential microbial starter for Suanyu industrial production.

为了更好地预测食品加热过程中的品质变化,采用动力学方法对鱼丸煮制过程中成熟品质因子(颜色、剪切力)和过热品质因子(水分含量)变化进行反应动力学测定和分析.结果表明,煮制过程中鱼丸亮度值、白度值和水分含量的变化均遵循一级反应动力学模型,而剪切力的变化遵循零级反应动力学模型.鱼丸亮度值和白度值的z值分别为19.37和33.43℃,Ea值分别为119.99和69.52 kJ/mol;过热品质因子水分含量的Ea值为39.39 kJ/mol,z值为59.11℃,大于成熟品质因子(亮度值、白度值)的z值,满足烹饪操作优化的前提条件,证明鱼丸在煮制过程中存在优化空间,为推进鱼丸产业化生产提供基础数据.

To explore the effect of commercial Saccharomyces cerevisiae on the quality of traditional "Wanergao" for reasonable consuming guidance, the dominant microbes, physicochemical property, free amino acid content, texture, and sensory properties during fermentation of "Wanergao" were illustrated in this paper. Compared with the samples in the control group, "Wanergao" samples in the two groups that were subjected to S. cerevisiae inoculation had weaker acidity (the pH values dropped from 4.39 ± 0.08 to 4.36 ± 0.07 and 4.36 ± 0.07 within 2 h during fermentation), higher fermenting rate (volume increased from 100 ± 1.31 to 305 ± 4.61 and 316 ± 4.93 mL separately within 3 h), and the dominant lactic acid bacteria and yeast being leukonid and S. cerevisiae. More amylose, ethanol, and free amino acid were detected in "Wanergao" produced with S. cerevisiae inoculation compared with "Wanergao" produced by sourdough. The two kinds of "Wanergao" presented various hardness (2318 ± 112, 2279 ± 103), springiness (0.76 ± 0.03, 0.71 ± 0.03), chewiness (1.43 ± 0.05, 1.41 ± 0.06), and cohesiveness (0.68 ± 0.03, 0.62 ± 0.03) after fermentation. The result of sensory analysis revealed that "Wanergao" in the S. cerevisiae group had higher elasticity, aroma, and restoring force. The experiment demonstrated that "Wanergao" produced by using S. cerevisiae is a kind of fermented rice product with rich fragrance, high amount of nutrients, and strong elasticity.

Abstract This study characterized the changes in the microbiological, physicochemical properties of Suan rou during fermentation via three different techniques (Technique A is a traditional production process. Based on technique A, technique B adds a total of 200 g of sucrose to the thinly sliced meat, and technique C changes the amount of salt in the thinly sliced meat to 200 grams.). Compared to batch A, the samples from batches B and C featured more rapid reduction in pH and generated more TA. Myofibrillar proteins in batches B and C showed higher degradation rate, and several low‐molecular‐weight metabolites were determined on the basis of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) gel lanes. The contents of thiobarbituric acid (TBARS) and total volatile base nitrogen (TVB‐N) and the growth of spoilage bacteria and pathogens were suppressed in the three batches. A relatively compatible acid–salinity proportion was presented in the Suan rou of batches A and B compared with that of batch C. The results show that the Suan rou made by B technology was more palatable acid flavor and abundant nutrition.

通过采用动力学的方法对酱卤猪肉在煮制过程中的过热品质因子(颜色、剪切力和水分含量)的变化进行测定和分析.结果表明:酱卤猪肉在煮制过程中,其颜色、剪切力和水分含量的变化都符合一级反应动力学.颜色L*值的z值为47.85℃,Ea值为51.31 kJ/mol,颜色a*值的z值为45.05℃,Ea值为54.47 kJ/mol;剪切力的z值为37.04℃,Ea值为66.14kJ/mol;水分含量的z值为52.63℃,Ea值为46.57 kJ/mol,均大于酱卤猪肉感官成熟品质因子的z值,满足成熟值理论提出的烹饪优化前提.本研究证明了酱卤猪肉在烹饪过程中存在优化空间,动力学参数的测定为酱卤猪肉煮制过程的优化提供了基础数据.

ABSTRACT Microorganisms and physiochemical characteristics were determined in traditional high-salt fermented fish products from six different regions. Results indicated that Lactobacillus content was 7.14–7.65 log CFU/g, and yeast content was 6.21–6.54 log CFU/g in the high-salt fermented fish samples. Enterobacterium content was below the detectable limit, and the dominant Lactobacillus species was Lactobacillus plantarum. The pH value was 4.14–4.73, and the protein content reached 19.37–28.38%. The sodium dodecyl sulfate-polyacrylamide gel electrophoresis results showed that myofibrillar proteins in fish were obviously degraded. Trichloroacetic acid-soluble peptide content was 901–1061 mg/tyrosine kg, and the fat and NaCl contents were 0.92–4.79% and 5.59–7.44%, respectively. Free amino acids and free fatty acids were 1332–2380 mg/100 g and 8.95–23.4 mg/fat g, respectively. The content of thiobarbituric acid reactive substances was 1.97–4.26 mg/kg, the total volatile basic nitrogen was 12.7 ~ 38.9 mg/100 g, and the content of biogenic amine was 26.3–34.6 mg/kg.