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This study aimed to investigate the textural changes of cooked germinated brown rice (GBR) during freeze-thaw treatment and propose a strategy for enhancing its texture using magnetic field (MF). Seven freeze-thaw cycles exhibited more pronounced effects compared to 7 days of freezing, resulting in increases in GBR hardness by 85.59 %-164.36 % and decreases in stickiness by 10.34 %-43.55 %. Water loss, structural damage of GBR flour, and starch retrogradation contributed to the deterioration of texture. MF mitigated these effects by inhibiting the transformation of bound water into free water, reducing water loss by 0.39 %-0.57 %, and shortening the phase transition period by 2.0-21.5 min, thereby diminishing structural damage to GBR flour and hindering starch retrogradation. Following MF treatment (5 mT), GBR hardness decreased by 21.00 %, while stickiness increased by 45.71 %. This study elucidates the mechanisms through which MF enhances the texture, offering theoretical insights for the industrial production of high-quality frozen rice products., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Bayberry juice is favored for its unique taste and flavor, while heat sterilization tends to reduce the aroma quality during processing, which limits its acceptability to consumers. To address this issue, we use exogenous polyphenols to regulate flavor compounds to improve the product quality. Total 13 differential key aroma-active compounds were identified between fresh bayberry juice (FBJ) and heat-sterilized bayberry juice (HBJ) using aroma extract dilution analysis (AEDA), orthogonal partial least squares-discriminant analysis (OPLS-DA) and odor activity values (OAVs). Further, eight polyphenols were added to investigate their influences on the aroma quality of HBJ respectively. The results showed that all tested polyphenols could maintain the aroma profile of HBJ closer to FBJ and improve the odor preference of HBJ, among which resveratrol and daidzein were most effective. Their aroma molecular regulatory mechanism involved enhancing the characteristic aroma of bayberry and reducing the certain off-flavored compounds produced by heat sterilization., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Application of the traditional immunochromatographic assay (ICGA) has been limited by its poor sensitivity. The objective of this study was to increase the sensitivity of the traditional ICGA. A dual-mode ICGA (D-M ICGA) was developed by combining a nanozyme-assisted signal-amplification strategy with a magnetic-nanoparticle-based flow-speed-control strategy. Salmonella typhimurium can be detected simultaneously based on color and magnetic signals in the detection area of the D-M ICGA strip. The calculated limits of detection of 50 cfu·mL -1 and 75 cfu·mL -1 in the color and magnetic modes, respectively, were approximately 1000 times lower than those of the traditional ICGA. The selectivity and practical applicability of the D-M ICGA were also confirmed in this study. The results prove that the D-M ICGA is an assay that could be used for Salmonella typhimurium detection and can be easily adapted to detect other pathogenic bacteria., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Health-promoting anthocyanins in blood oranges can be enriched via appropriate postharvest storage conditions. Here, we explored the changes of anthocyanin accumulation and volatile profiles of Tarocco blood oranges (Citrus sinensis L. Osbeck) treated by the low temperature alone and combined with ethephon (2 mg/mL) during 50 days of storage. The combination treatment of ethephon and low temperature (8 o C) significantly enhanced the levels of total anthocyanins (10.91 ± 0.25 mg/100 g) and individual cyanidin derivatives relative to low-temperature treatment alone. The increases of six cyanidin derivatives and three delphinidin derivatives identified by LC-MS/Q-TOF were consistent with the variation in total anthocyanins. Ethyl butanoate, ethyl 2-methylbutyrate, ethyl hexanoate, ethyl undecanoate, linalool, and d-limonene were identified as main contributors to overall aroma of fresh blood oranges. Volatile compositions and concentrations were decreased under different treatments of ethephon and temperatures, while ethephon could alleviate the loss of activity volatiles during cold storage., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Thermal process is the most important way of treating foods. Heat energy inputted into the natural food system induces the depolymerization of multi-scale structures of matrix, and causes the intramolecular and intermolecular interactions of different nutrients. It attacks and breaks the original polymeric molecule structures and the functional properties of macronutrients such as carbohydrates, proteins and lipids. Micronutrients such as vitamins and other novel functional ingredients are also thermally converted. The heat-induced conversions of nutrients are slightly or totally with discrepancy in simple-, simulated- and real-food systems, respectively. Thus, this review aims to extensively summarize the heat-induced structural characteristics, thermal conversion pathways and pyrolysis mechanism of nutrients both in simple and complex food matrices. The structural change of each nutrient and its thermal reaction kinetics depend on the molecule structure and polymeric characteristic of the unit substances in the system., (Copyright © 2021. Published by Elsevier Ltd.)

Cereal germ (CG), a by-product of grain milling, has drawn much attention in the food industry because of its nutritional and functional advantages. Nowadays, the utilization of cereal germ from animal feeds to foodstuff is a popular trend. CGs have high content of polyunsaturated fatty acids in their lipids (43.9-64.9% of total fatty acids), but they are also induced to oxidative rancidity under the catalytic reaction of enzymes. Chemical and structural properties of lipids in CGs are affected by different treatments. Thermal and non-thermal effects prevent lipid oxidation or promote lipid combination with starch/protein in CG. Thus, the functional properties and final quality of CG are directly changed. In this review, the chemical composition and application of CGs especially the endogenous lipids are summarized and the effects of various processes on CG lipids/matrices are discussed for CG future development., (Copyright © 2021. Published by Elsevier Ltd.)

Campylobacter jejuni (C. jejuni) is considered one of the most common cause of human gastroenteritis. Aiming to detect C. jejuni in food products rapidly and sensitively, a dual mode lateral flow assay, based on the peroxidase mimicking and surface enhanced Raman scattering (SERS) enhancement properties of platinum coated gold nanorods (AuNR@Pt), was developed in this study. Under color mode and SERS mode, the proposed assay showed good linear response in the range of 10 2 -10 6  cfu/mL and 10 2 -5 × 10 6  cfu/mL with limits of detection of 75 cfu/mL and 50 cfu/mL, respectively (S/N = 3). Furthermore, the reliability of the dual-readout lateral flow assay (LFA) was successfully demonstrated by the application on milk samples, in which the recoveries ranged from 89.33% to 107.62%. Overall, the immunochromatographic assay developed in this work is promising and has good chance to be employed for sensitive detection of C. jejuni in food products., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The physicochemical properties of broad bean paste koji made from extruded and traditional steam-cooked raw materials were investigated by scanning electron micrographs (SEM), confocal laser scanning micrographs (CLSM), circular dichroism (CD) and Molecular weight (Mw) analysis. The results showed that the protease activity of koji made from the extruded materials was higher than that of the traditional cooking method. A network porous structure in the extruded samples was observed by SEM. Furthermore, the CLSM results showed that the starch of the extrudate was embedded well in its protein network. CD spectroscopy implied that the α-helix decreased while the β-turn and random coil increased after both treatments. Mw analysis determined that the starch molecules were degraded during extrusion, the proportion of micromolecules was more in the extruded samples than in the steam-cooked samples. However, the chain length distribution of starch exhibited no significant difference between the extruded and steam-cooked broad beans., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Ochratoxin A (OTA) poses a serious threat to the health of human beings and animals. In this paper, a simple and sensitive electrochemiluminescence (ECL) aptasensor was constructed to detect OTA based on electrochemiluminescence resonance energy transfer (ECL-RET) and a nicking endonuclease-powered DNA walking machine. Originally, the signal of cadmium sulfide semiconductor quantum dots (CdS QDs) was quenched efficiently by Cy5. After the addition of OTA, the walker autonomously hybridized with Cy5-labeled DNA and released plenty of Cy5-DNA from the electrode surface with the help of a nicking endonuclease. As a result, the signal of CdS QDs recovered efficiently. As an artificial and popular signal amplification technique, the DNA walking machine greatly improved the sensitivity. Under optimal conditions, the aptasensor not only detected OTA in a linear range from 0.05 nM to 5 nM with a detection limit of 0.012 nM (S/N = 3), but also showed an excellent selectivity for OTA over other mycotoxins., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

A simple, rapid and economic lateral flow immunochromatographic assay (LFICA) was designed for ultrasensitive detection of β-conglutin. Instead of antibodies and gold nanoparticles (AuNPs) used in conventional LFICA, a cognate aptamer duo, binding to β-conglutin and Fe 3 O 4 @Au core-shell nanoparticles, was applied in this study. An enzyme signal amplification strategy was used to enhance sensitivity. In addition, a new magnetic enrichment strategy was employed to further enhance sensitivity of the assay, slowing down movement of the capture probe (i.e., Fe 3 O 4 @Au nanostructures) using an external magnetic field. The novel LFICA assay can be completed within 20 min and achieved a detection limit of 8 fM, a thousand-times lower than similar assays without magnetic focusing. Overall, our results demonstrated the potential for the proposed LFICA sensor in rapid detection of β-conglutin without any special analytical expertise or instrumentations., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Patulin (PAT) is a type of mycotoxin which can compromise both food quality and human health. Due to its harmful effects, strict monitoring of PAT contents in food systems is necessary. A novel kind of bioassay was proposed for determining PAT based on the fluorescent resonant energy transfer (FRET) strategy. The exonuclease-catalyzed target recycling strategy was employed to improve the sensitivity of the FRET system. The results showed that the linear range extends from 0.01 ng/mL to 100 ng/mL. Furthermore, the average recoveries ranged from 93.33% to 105.21%, confirming the reliability of this method. The total analysis time for our assay developed is about 50 min. Compared to traditional analytical methods, the developed assay is more stable and has a significantly lower detection of limit (0.003 ng/mL). We believe the approach developed in this study would be useful for high-throughput screening of PAT in food industry and government laboratory., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Metal-rich thermal-solid enzymatic processing of rice combined with yeast fermentation was investigated. 8 Metal ions were exogenously supplied at 0.05, 0.5 and 5mmol/100g (MG) rice prior to static high pressure enzymatic cooking (HPEC) and dynamic enzymatic extrusion cooking (EEC). Treated rice and its fermentation efficiency (FE) were characterized by rapid viscosity analyzer (RVA), UV-Vis, FT-IR and atomic absorption spectrophotometer (AAS). The optimum pH range of enzyme in solid system (>4.9) was broader than in a liquid system (>5.5). Cations decreased enzymatic activity in HPEC probably due to metal-induced aggregation of rice matrix with reduced reacting area as well as strengthened structure of starch/polysaccharides modified by metals. While using the EEC with mechanical mixing/shearing, relative activity was activated to 110 and 120% by Mg 2+ (0.05-0.5MG) and Ca 2+ (0.05-5MG), respectively. Furthermore, the effectiveness of residual ions to promote further FE was found to follow the order: Ca 2+ >K + >Zn 2+ >Mg 2+ >Mn 2+ >Na + ≈Control>Fe 2+ >Cu 2+ , individually., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

A facile strategy was successfully developed for the detection of zearalenone (ZEN). In this assay, highly fluorescent upconversion nanoparticles were synthesized and conjugated with the complementary oligonucleotide of ZEN aptamer for use as signal probes. Magnetic nanoparticles immobilized with the ZEN aptamer were assigned as capture probes. The results exhibited that the linear correlation between the decreased luminescence intensity of the signal and the concentration of ZEN was very strong (R 2 =0.9957) in the range of 0.05-100μg/L. In addition, the limit of detection of the proposed method (0.126μg/kg for corn and 0.007μg/L for beer) was significantly lower than the existing methods. Furthermore, the reliability of the competitive immunoassay format was validated by comparing the results determined in real food samples to those obtained from a commercially available method. Overall, the novel aptasensor have showed great potential for rapid and accurate ZEN determination., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

For the purpose of investigating the effect of enzyme concentration (EC), barrel temperature (BT), moisture content (MC), and screw speed (SS) on processing parameters (product temperature, die pressure and special mechanical energy (SME)) and product responses (extent of gelatinization (GE), retention rate of total phenolic content (TPC-RR)), rice flour extruded with thermostable α-amylase was analyzed by response surface methodology. Stepwise regression models were computed to generate response surface and contour plots, revealing that both TPC-RR and GE increased as increasing MC while expressed different sensitivities to BT during enzymatic extrusion. Phenolics preservation was benefited from low SME. According to multiple-factor optimization, the conditions required to obtain the target SME (10kJ/kg), GE (100%) and TPC-RR (85%) were: EC=1.37‰, BT=93.01°C, MC=44.30%, and SS=171.66rpm, with the actual values (9.49kJ/kg, 99.96% and 87.10%, respectively) showing a good fit to the predicted values., (Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.)

The interactions between pullulanase and chitosans of different molecular weights (Mw) were comprehensively studied, and their applications in pullulanase immobilization onto Fe3O4-κ-carrageenan nanoparticles upon chitosan-pullulanase complexation were also evaluated. Chitosan (CS) complexation with pullulanase was found to be dependent on pH and chitosan Mw. The critical pH of structure-forming events during complexation shifted significantly (p<0.05) to a lower pH with a low Mw chitosan (50kDa) compared to other chitosan types. Binding constants for the chitosan-pullulanase interaction increased in the following order: CS-500

In order to determine the effect of enzymatic extrusion on the physicochemical and antioxidant properties of rice/soybean mixture, different mass ratios (100/0, 95/5, 85/15, 70/30, 50/50 and 25/75%, w/w) were treated with thermostable α-amylase. The reduced special mechanical energy and the enhanced product temperature were closely and regularly linked with the increase of soybean content. The bulk density and water solubility index increased, and the water absorption index and viscosities decreased remarkably after enzymatic extrusion, however, the modification caused by α-amylase were dramatically eliminated with the increase of soybean content to ∼50%. Moreover, the addition of enzyme exhibited an improvement of the total phenolic/flavonoid content (TPC/TFC) and antioxidant capacities compared to traditional extrusion. The TPC/TFC retention of extrudate (ratios of 85/15 and 70/30%) attained over 90%, but dramatically decreased (72.91 and 67.81%, respectively) with soybean added to 75%, probably due to the great reduction of starch substrate for enzymatic hydrolysis., (Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.)

The application of attenuated total reflectance infrared spectroscopy (ATR-IR), Raman spectroscopy (RS) and combination of ATR-IR and RS for measurements of total antioxidant capacity (TAC) and total phenolic content (TPC) of Chinese rice wine (CRW) were investigated in this study. Synergy interval partial least-squares (SiPLS), support vector machine (SVM) and principal component analysis (PCA) were applied to process the merged data from two individual instruments. It was observed that the performances of models based on the RS spectra were better than those based on the ATR-IR spectra. In addition, SVM models based on the efficient information extracted from ATR-IR and RS spectra were superior to PLS models based on the same information and PLS models based on ATR-IR or RS spectra. The overall results demonstrated that integrating ATR-IR and RS was possible and could improve the prediction accuracy of TAC and TPC in CRWs., (Copyright © 2015 Elsevier Ltd. All rights reserved.)