Quantitation of milk proteins in thermally treated milk samples and commercial food products by ELISA test kits.

This study evaluated four ELISA kits for quantitation of milk proteins in thermally treated milk samples and food products. How reference materials may be used for comparison of kit performance was examined. Protein contents determined by Veratox Total Milk generally reflected those determined by the 660 nm total protein assay. BioKits BLG Kit was less affected by thermal treatment but resulted in overestimation of protein contents in samples that were boiled, autoclaved or dry-heated at ≤149 °C, while ELISA Systems Casein (ES Casein) and Beta-Lactoglobulin (ES BLG) assays underestimated protein levels in these samples. The four kits gave similar results for ice cream. Veratox registered higher concentrations in all products tested but its sensitivity was greatly lowered in retorted products. ES Casein underperformed Veratox for baked and retorted products. BioKits BLG maintained a better sensitivity towards fried, baked and retorted products while ES BLG exhibited reduced sensitivity for these products.

From Palm to Plate: Unveiling the Potential of Coconut as a Plant-Based Food Alternative.

This review investigates coconut as a sustainable and nutrient-rich plant-based alternative to traditional animal-based food sources. We have explored the nutritional profile, culinary versatility, particularly focusing on the use of coconut meat, milk, cream, and oil in diverse dietary contexts when consumed in balance. Comparative analysis with animal-derived products reveals the high content of medium-chain triglycerides (MCTs), essential vitamins, and minerals in coconut, contrasted with its lower protein content. Researchers have underscored the environmental sustainability of coconut, advocating for its role in eco-friendly food production chains. We have also addressed challenges like potential allergies, nutritional balance, sensory attributes, and consumer motivations for coconut-based products, in terms of understanding the market dynamics. In conclusion, this review positions coconut as a promising candidate within sustainable diet frameworks, advocating for further research to augment its nutritional value, sensory characteristics, and product stability, thereby facilitating its integration into health-conscious and eco-centric dietary practices.

The metabolism and transformation of casein-bound lactulosyllysine in vivo: Promoting dicarbonyl stress and the formation of advanced glycation end products accompanied by systemic inflammation.

Lactulosyllysine (LL) widely exists in thermally processed dairy products, while the metabolism and transformation of LL remain poorly understood. We aimed to elucidate the metabolic pathways of LL and its impact on body health by subjecting C57BL/6 mice to a short-term ll-fortified casein diet. Our findings indicated that casein-bound LL might be metabolized and transformed into 3-deoxyglucosone through fructosamine-3-kinase (FN3K) in vivo, which promoted α-dicarbonyl stress, ultimately leading to the formation of advanced glycation end products (AGEs) in various tissues/organs, accompanied by systemic inflammation. The levels of AGEs formation in tissues/organs at various stages of casein-bound LL intake exhibited dynamic changes, correlating with alterations in the expression of FN3K and α-dicarbonyl compounds metabolic detoxification enzymes. The negative effects induced by casein-bound LL cannot be fully reversed by switching to a standard diet for equal periods. Consumption of dairy products rich in LL raises concerns as a potential risk factor for healthy individuals.

Evaluation of ELISA Test Kits for Detection of Milk Protein in Frying Oil Treated at Different Temperatures.

Milk is a common ingredient in fried foods. Allergen cross-contact can occur through the reuse of frying oil. To enable assessment of the allergy risk of reused oil, methods for quantification of milk protein in oil are needed. This study evaluated four commercial ELISA test kits in comparison with the 660 nm total protein assay for the detection of milk protein in oil after frying. Corn oil spiked with nonfat or whole milk powder were fried at 150 °C or 180 °C for 3 min and were analyzed by ELISA kits either directly or after preextraction with phosphate-buffered saline containing 0.05% Tween (PBST). All four ELISA kits performed well in quantifying milk protein in unheated oil, achieving normalized recoveries of 72.1-115.9% compared with that determined in reference solutions (PBST spiked with nonfat or whole milk powder, 100%). Frying lowered the amount of protein detected, but the extent of reduction differed between test kits. In nonfat milk powder-spiked oil fried at 150 °C, normalized recoveries determined by Veratox Total Milk and BioKits BLG Assay (49.9% and 43.6%, respectively) were higher than that determined by the 660 nm assay (25.4%). Normalized recoveries determined by ELISA Systems Casein and Beta-Lactoglobulin (BLG) kits were substantially lower (9.7% and 2.4%, respectively). In samples fried under typical frying temperature (180 °C), very little protein (0.1-7.4%) was detected. Inclusion of PBST preextraction improved the detection of the two test kits targeting BLG but lowered the level of protein detected by Veratox and ELISA Systems Casein in fried samples. Overall, the ELISA kits evaluated could effectively quantify milk protein in unheated oil without the need to remove the oil phase prior to analysis. Heat treatment was the key factor negatively affecting protein quantitation. Such impact needs to be considered when ELISA test results are used for assessing the allergy risk of reused frying oil.

Effects of Different Frying Oils Composed of Various Fatty Acids on the Formation of Multiple Hazards in Fried Pork Balls.

Oil oxidation products can react with food substrates to produce harmful substances, and oil saturation is closely related to oil oxidation in the process of frying. Therefore, the influence of the composition of fatty acids in oil on the formation of harmful substances in fried pork balls was explored. The five frying oils with the lowest unsaturated fatty acid (UFA) content, ranked in ascending order, were palm oil, peanut oil, soybean oil, corn oil, and colza oil (64.94%, 79.94%, 82.65%, 83.07%, and 92.26%, respectively). The overall levels of four harmful substances (acrylamide, polycyclic aromatic hydrocarbons, heterocyclic amines, and trans fatty acids) found in the oil used to fry pork balls followed a descending order: canola oil, corn oil, peanut oil, soybean oil, and palm oil (33.66 µg/kg, 27.17 µg/kg, 23.45 µg/kg, 18.67 µg/kg, and 13.19 µg/kg, respectively). This order was generally consistent with the trend in the content of UFAs. Therefore, the formation of harmful substances is closely related to the saturation of oil. Compared with other frying oils, soybean oil as a household oil produces relatively low amounts of harmful substances and has less negative impact on the quality (oil content, moisture content, and higher protein digestibility) of fried products.

[Spatial Network of Urban Heat Environment in Beijing-Tianjin-Hebei Urban Agglomeration Based on MSPA and Circuit Theory].

Rapid urbanization has increased the complexity of the urban heat environment system, which has negative impacts on the health of the urban ecological system and the human habitat. By combining theories and technologies such as geographic information systems, remote sensing, morphological spatial pattern analysis, and circuit theory with data from MODIS land surface temperature production, urban heat island patches in the Beijing-Tianjin-Hebei urban agglomeration were quantitatively identified in terms of their spatial and temporal distribution characteristics and their spatial and temporal transfer paths. This foundation revealed the geographical network structure of the urban heat environment as well as the spatial and temporal evolution process of critical corridors. According to the findings, urban heat island patches covered 16610 km2 in 2020, accounting for 7.68% of the study area. In the Beijing-Tianjin-Hebei urban agglomeration, both the area and the number of urban heat island patches considerably increased between 2005 and 2020, going from being dominated by isolated island types of urban heat island patches in 2005 to being dominated by core types in 2020. In particular, the non-urban heat island patches, core type, and edge type of urban heat island patches in 2005 were the major ancestors of the core type and edge type urban heat island patches in 2020. In the Beijing-Tianjin-Hebei urban agglomeration, there were more urban heat environment source sites, corridor length, densities, and present densities in 2020 than there were in 2005. The sensitive corridor was found to be the predominant type of urban heat island corridor in the Beijing-Tianjin-Hebei urban agglomeration in 2020. The number of sensitive corridors increased the highest in the period from 2005-2020. As the coefficient of urban heat environment corridors increased concurrently, it was apparent that the urban heat environment corridor had a propensity to grow continuously in the Beijing-Tianjin-Hebei urban agglomeration. The active adaptation and mitigation measures of the urban heat environment were proposed, and a spatial network model of the urban heat environment was finally provided. To adapt to, mitigate, and promote urban sustainable development risks, these research findings will serve as a paradigm for the identification of the urban heat environment spatial network actively and methodically.

Coffee prevents IQ-induced liver damage by regulating oxidative stress, inflammation, endoplasmic reticulum stress, autophagy, apoptosis, and the MAPK/NF-κB signaling pathway in zebrafish.

2-Amino-3-methylimidazole[4,5-f]quinoline (IQ), one of heterocyclic amines (HCAs) produced in proteinaceous foods upon heating, is recognized as a carcinogen. Previous studies have confirmed that IQ intake can cause liver damage in zebrafish. In the current study, we revealed the protective effects of coffee against IQ-induced liver damage. We exposed one-month-old wild-type zebrafish to IQ (80 ng/mL) and coffee at 50 mg/L, 100 mg/L, and 300 mg/L for 35 days. Markers of oxidative stress, inflammation, endoplasmic reticulum stress (ERS), autophagy, and apoptosis in the liver were assessed to explore the potential mechanisms of the protective effects. The results showed that coffee effectively improved IQ-induced liver damage by reducing ALT, AST, TC, TG, and LDL-C levels, increasing HDL-C level, and restoring hepatic morphology. Moreover, coffee showed an antioxidative effect by increasing GSH, GSH-Px, GST, CAT, and SOD levels and attenuating ROS and MDA contents. Additionally, coffee reduced the NO, iNOS, TNF-α, IL-6, IL-1ß, and IL-12 expression levels, presenting an anti-inflammatory effect. Furthermore, coffee protected against ERS, autophagy dysfunction, and apoptosis by decreasing the GRP78, CHOP, and p62 while increasing the Atg5-Atg12, Beclin1, LC3-II, and Bcl-2 expression levels. TUNEL results showed that coffee rescued IQ-induced hepatocyte apoptosis. In addition, coffee interrupted the MAPK/NF-κB signaling pathway by suppressing the phosphorylation expressions of JNK, ERK, p38, p65, and IκB. These findings indicated that coffee prevents IQ-induced liver damage with antioxidative, anti-inflammatory, anti-ERS, anti-apoptotic, and pro-autophagic effects, thus to serve as a functional beverage with potential health benefits.