Journal of Food Processing and Preservation

The aim of the study was to determine the effects of oven, microwave (MW), and infrared (IR) drying technology on the drying kinetics, physicochemical properties, and β-carotene retention of the dried orange-fleshed sweet potato flour (OFSP). Fresh OFSP slices were dried in an oven (40°C), MW (80 W), IR (250 W), MW-IR (), and freeze-drying (-45°C, 100 kPa) and milled into flour. Hot air at a constant temperature was applied to all thermal drying technologies (40°C, 4.5 m/s air velocity). The drying rate of the MW-IR drying method was the fastest (45 min), followed by MW (60 min), IR (120 min), and oven (180 min). The Page model was most suitable for the oven-drying method, the Lewis model for IR drying, and Henderson and Pabis for IR and Logarithmic for the MW-IR method. The pasting and thermal properties of the flours were not significantly () affected by the different drying methods. However, IR- and MW-IR-dried flours showed a higher final viscosity when compared to other drying methods. MW-IR drying methods, IR, and MW showed a higher water solubility index, while the oven and freeze-drying methods showed a lower solubility index. MW-IR drying methods showed a higher retention of β-carotene (85.06%). MW also showed a higher retention of β-carotene (80.46%), followed by IR (66.04%), while oven and freeze-drying methods showed a lower retention of β-carotene. High β-carotene retention in the produced flour is due to the faster drying method, and these flours can be used in food-to-food fortification to address vitamin A deficiency.

Soluble sugar is one of the important characteristic metabolites contributing to the flavor quality of tea. However, little is known about the changes and metabolic pathways of sugar in summer–autumn black tea varieties during the solid-state fermentation of Ganoderma lucidum. Therefore, this study is aimed at investigating the effects of the solid-state fermentation of Ganoderma lucidum on soluble sugar metabolism in three summer–autumn black tea varieties. In this study, we combined targeted metabolomics technology, gas chromatography-mass spectrometry, and multivariate statistical analysis to reveal the metabolic rules of 13 different sugars in three varieties of summer–autumn black tea under the action of Ganoderma lucidum. Using multivariate statistical analysis, 8 common key sugar differential metabolites were selected from the three groups of samples: D-fructose, trehalose, lactose, maltose, D-galactose, glucose, L-rhamnose, and xylitol. The eight different sugars contributed to the quality difference between Ganoderma lucidum tea and black tea in this study. To better explore the patterns of sugar changes, the metabolic pathways of 13 different sugars were screened and analyzed. The result revealed that the solid-state fermentation of Ganoderma lucidum increased the sweet characteristics and decreased the bitter characteristics of the three summer–autumn black tea varieties. In addition, these results showed that the solid-state fermentation of Ganoderma lucidum could produce lactose in tea, reduce glucose and fructose contents, and increase xylitol content. The solid-state fermentation of Ganoderma lucidum can regulate soluble sugar metabolism in three summer–autumn black tea varieties, leading to an improvement in their quality. This study has potential practical significance for regulating the flavor quality of summer–autumn tea.

The rising demand for fiber-rich food products has fuelled the exploration of innovative approaches to enhance their dietary fiber content. Although adding dietary fiber-rich materials into pasta formula can increase the dietary fiber content, this approach counters several technological problems as the cooking and textural properties of the resulting pastas are usually negatively affected. This study is aimed at utilizing sweet corn “milk” residue (SCMR), a food by-product, and transglutaminase to develop fiber-rich pasta. Durum wheat semolina was replaced by SCMR powder at the ratio of 0 (control), 5, 10, 15, and 20% to make SCMR-fortified pasta. The chemical compositions and cooking and textural properties of the fortified pasta were then quantified. As the replacement ratio increased, the dietary fiber content, total phenolic content (TPC), and antioxidant properties of pasta were considerably improved while the cooking and textural attributes were negatively impacted. At 20% SCMR fortification, the dietary fiber content and TPC of the pasta were increased by 3.2 and 1.2 times, respectively, while the cooking loss increased by 73% as compared to those of the control pasta. Meanwhile, the chewiness, cohesiveness, tensile strength, and elongation rate at break of the 20% SCMR-fortified pasta were reduced by 19%, 26%, 21%, and 65%, respectively, compared to those of the control pasta. To improve the cooking properties and the textural properties of the fortified pasta, transglutaminase was added to the pasta dough with 20% SCMR. The effect of transglutaminase was enzyme-dose dependent. The cooking and textural qualities of pasta were improved as enzyme concentration increased 0 to 0.75 U/g protein and declined as the enzyme concentration increased from 0.75 to 1.25 g/U protein. At the optimal concentration of transglutaminase (0.75 U/g protein), the cooking loss reduced by 16% while the chewiness, cohesiveness, tensile strength, and elongation rate increased by 18%, 11%, 31%, and 32% compared to those without transglutaminase. Novelty Impact Statement. This study focuses on developing the dietary fiber-enriched pasta using sweet corn “milk” residue and transglutaminase enzyme. The results showed that replacing 20% durum wheat semolina with SCMR powder significantly enhanced the dietary fiber and total phenolic content of the pasta but negatively affect the cooking and textural properties of the pasta. Adding transglutaminase at 0.75 U/g protein to the SCMR-semolina blended dough successfully restored the adverse effects of SCMR on the cooking and textural properties. This study showed that dietary fiber-enriched pasta with improved cooking and textural properties can be prepared using the combination of SCMR and transglutaminase.

Globally, large quantity of animal byproducts is generated from the slaughter of food animals, but there is lack of research articles related to drying of these byproducts and its use as pet food. Therefore, this study was conducted with the aim of utilization of intact whole buffalo liver by drying for pet treat, evaluating its shelf life and palatability. The intact liver surface was superficially sliced, and the surface was pierced. Thereafter, the livers were pretreated in 3% sugar and 4% salt solution (1 : 3 ) for 3 h followed by microwaving for 4 min and hot air drying at 60°C for 40 h (designated as T2L). The livers which were dried the same as T2L except surface piercing were referred as T1L, whereas the livers dried only using hot air oven were referred as control (CL). The moisture and protein contents of the dried CL and T2L were found to be 28.46% and 14.29% and 43.85% and 52.76%, respectively. Sodium dodecyl sulphate–polyacrylamide gel electrophoresis (SDS-PAGE) image of T2L revealed the presence of few low as well as high molecular weight protein bands which were absent in CL and T1L indicating a comparatively lower level of protein degradation in T2L. The shelf life of T1L and T2L samples based on microbiological and lipid oxidation analyses was found to be more than 60 days at 25 and 4°C. Palatability studies using dogs showed that all dried samples were highly palatable. Thus, it could be concluded that intact buffalo liver could be dried using surface slicing, with/without piercing followed by salt and sugar pretreatment, 4 min microwaving, and hot air drying at 60°C for 40 h. Future study should focus on the sensory properties such as aroma, texture, and flavor and sensory analysis of the dried liver by human.

Passion fruits are susceptible to numerous postharvest challenges including weight loss, ethylene production, peel shrinkage, microbial growth, and pulp liquefaction. To mitigate these issues, yellow passion fruits were treated with hydroxypropyl cassava starch zinc oxide (HCS-ZnO) nanoparticles at varying concentrations. Fruits were stored at 10°C for 42 days, and the treated fruits underwent periodic assessments for weight loss, electrical conductivity, reducing sugar, total soluble solids (TSS), titratable acidity, and peel color. The results showed that a 0.8% HCS-ZnO nanoparticle coating could significantly reduce the weight loss of passion fruit during storage. However, compared to other treatments, a 0.2% HCS-ZnO nanoparticle coating demonstrated superior preservation of physicochemical properties, delayed discoloration, slowed ripening, maintained cell membrane integrity (electrical conductivity 1337 μs/cm), and reduced nutrient loss (titrable acidity 3.35 g/100 mL, TSS 17.9%, reducing sugar 5.1 g/100 g) at 42 days of storage. This innovative approach holds promise for commercial application, offering a sustainable solution to mitigate postharvest losses of passion fruit. The study underscores the potential of HCS-ZnO nanoparticles as effective coatings to uphold fruit quality and extend shelf life, presenting compelling insights for future fruit preservation strategies.

The study is aimed at determining how the quality of Antarctic krill (Euphausia superba) sauce (AkS) changed over time, including changes in color, moisture content, acid value (AV), peroxide value (POV), thiobarbituric acid reactive substance (TBARS), aerobic plate count, and sensory score. Quality variations and shelf life of AkS were estimated using kinetic model and back propagation (BP) neural network model. The results showed that sensory score, moisture content, and values of AkS declined as storage temperature increased at 4, 25, and 37°C. In addition, the values, values, AV, POV, and TBARS of AkS increased as storage duration increased, indicating that high storage temperature of the samples accelerated quality degradation. The primary reason for AkS degradation was the oxidation of proteins and lipids. The POV, TBARS, and total sensory evaluation rating exhibited a highly significant correlation, and therefore, POV and TBARS were selected as the indicators for the two models. The BP neural network outperformed the kinetic model in predicting quality changes over the whole storage period, with relative errors of less than 10%. In terms of shelf-life prediction, the BP neural network’s relative errors were 11.76% and 13.39% in POV and TBARS, respectively. POV and TBARS had experimental shelf lengths of 119 and 142 d, respectively. Compared with the kinetic model, the BP neural network model predicted the quality changes and shelf life of AkS with greater accuracy and stability. The findings offer fundamental insights and innovative concepts for the production of high-value Antarctic krill products, as well as the exploitation of Antarctic krill resources.