Objective To investigate the effects of different processes on nutritional compositions and minerals in the processing of tender Laminaria japonica. Methods In this paper, the effects of blanching and salting processes on the main nutritional compositions and minerals of tender Laminaria japonica during processing were studied. Results The content of water, crude protein, dietary fiber, crude fat, alginate, mannitol, iodine, amino acids, manganese, phosphorus, iron, and potassium in fresh tender Laminaria japonica were the highest, followed by blanched tender Laminaria japonica, and the lowest was salted tender Laminaria japonica, which might be due to the high temperature of blanching and the dehydration process of salting, resulting in varying degrees of loss of nutrients in tender Laminaria japonica. Amino acid composition analysis showed that fresh tender Laminaria japonica was more in line with the ideal protein pattern recommended by Food and Agricultural Organization of the United Nations/World Health Organization (FAO/WHO). Heavy metal content analysis showed that the content of heavy metal elements in tender Laminaria japonica met the food safety standards at home and abroad. The results of principal component analysis showed that the comprehensive scores of fresh tender Laminaria japonica was the highest and the quality was the best. After blanching and salting, the comprehensive nutritional quality of fresh tender Laminaria japonica decreased. Conclusion During the processing of tender Laminaria japonica, nutritional compositions and minerals are lost to varying degrees after blanching and salting. This study can provide a scientific basis for the high-value development, utilization, and sustainable development of tender Laminaria japonica in the future.

Objective To achieve rapid and non-destructive detection of lactic acid and total acidity during the fermentation process of sour meat. Methods Utilizing hyperspectral imaging technology, spectral reflectance images in the range of 408 to 1049 nm were collected to obtain spectral information of sour meat at different fermentation stages. After extracting the reflectance spectra from the regions of interest in the images, the kennard-stone algorithm (KS) was employed to divide the data into training and testing sets. The raw data underwent preprocessing through standard normal variate transformation (SNV) and multivariate scatter correction (MSC), followed by model establishment using partial least squares regression (PLSR). Feature wavelengths were extracted using the successive projection algorithm (SPA), competitive adaptive reweighted sampling (CARS), and uninformative variable elimination (UVE). Models were developed based on PLSR and compared with full-wavelength prediction models. Results The optimal prediction model for lactic acid in sour meat was SNV-CARS-PLSR, with a coefficient of determination (R²) of 0.9113 and a root mean square error of cross-validation (RMSECV) of 0.7236 for the training set, while the testing set yielded an R² of 0.9104 and RMSECV of 0.7342. The MSC-CARS-PLSR model for total acidity demonstrated the best predictive performance, with training set R² and RMSECV values of 0.9307 and 0.6782, respectively, and prediction set R² and RMSECV values of 0.8682 and 0.6907. Conclusion The models constructed using hyperspectral imaging technology have the potential to enable rapid and non-destructive detection of lactic acid and total acidity in sour meat, indicating significant application value.

Objective To study the difference of nutritional quality of different varieties of Prunus avium . Methods Taking 12 varieties of Prunus avium from Yantai of Shandong Province as the research object, the quality differences of different varieties of Prunus avium were analyzed by measuring the appearance indexes such as cross diameter and color difference, as well as the flavor and nutritional indexes such as soluble solids, organic acids, vitamin C, phenolic acids, flavonoids and anthocyanins. The one-way analysis of variance was used to clarify the differences in the content of each indicator among different varieties. The core quality indicators of Prunus avium were screened by correlation analysis, principal component analysis and cluster analysis. Results The soluble solids were found to be more than 15%, the titratable acid content was more than 0.5 g/100 g, and the purple-red fleshy cherry was rich in anthocyanins, and the determination of 26 quality indicators was simplified, 4 core indicators were determined to be chlorogenic acid, vitamin C, cyanidin-3-O-rutinoside, proanthocyanidins B₂. Based on the core indicators, Prunus avium could be completely separated by color, indicating that the core indicators were feasible. Finally, principal component analysis was used to comprehensively evaluate the quality of Prunus avium. According to the comprehensive score, it was found that the purple-red fleshy Russian cultivar had the best quality. The results of the measured quality index showed that it had the highest content of cyanidin-3-O-glucoside and rutin. Conclusion There are significant differences in the nutritional quality indexes of different varieties of Prunus avium. This paper provides data support for the construction of cherry quality indicator database, which is of great significance for standardizing the cherry quality evaluation system and promoting the high-quality development of the Prunus avium industry.

Objective To develop a highly sensitive detection method suitable for accurate qualitative and quantitative analysis of monosaccharide composition in edible fungi polysaccharides. Methods Four kinds of edible fungus polysaccharides samples: Lentinus edodes, Pleurotus eryngii, Hypsizygus marmoreus and Auricularia auricula were selected, after hydrolyzing with trifluoroacetic acid, and deriving with acetic anhydride, the sample was analyzed by gas chromatography-mass spectrometry (GC-MS/SIM). The specificity, precision, linear range, limits of detection (LOD) and limits of quantification (LOQ) of this method were investigated with mixed standards of 7 kinds of monosaccharides. At different m/z, the best linear relationship was used as the standard to select the most suitable quantitative ion for each monosaccharide. The stabilities and recoveries of the method under selected ion monitoring (SIM) mode were investigated using edible fungus polysaccharide samples. Results The results showed that m/z 115, m/z 103, m/z 115, m/z 115, m/z 115, m/z 115 and m/z 103 were selected as the characteristic quantitative ions of the corresponding derivatives of ribose, rhamnose, arabinose, xylose, mannose, glucose and galactose, respectively. The separation of each monosaccharide was greater than 1.2, and the linear relationship between each monosaccharide in SIM mode was good between 10.00-50.00 μg/mL, and the correlation coefficient (r²) was greater than 0.998. The LOD and LOQ were 5.75-22.23 ng/mL and 17.26-66.67 ng/mL, respectively. Using monosaccharide mixed standard and lentinan as sample matrix, it was proved that this method had good precision and stability, and the average recovery of each monosaccharide was between 94.4% and 101.3% under different standard adding levels. And the rationality of selecting the above characteristic ions was discussed by mass spectrometry analysis. Conclusion This method has good separation, precision and stability, and its sensitivity is higher than most similar detection methods reported so far. It is suitable for the detection of monosaccharide composition in various edible fungi polysaccharides.

Objective To establish an analytical mehod for the determination of nicotinamide mononucleotide (NMN) and nicotinamide adenine dinucleotide (NAD⁺) in health food by high performance liquid chromatography. Methods Determination was performed on Waters BEH-Amide column with mobile phase consisting of 0.1% phosphoric acid solution-acetonitrile (gradient elution). The flow rate was 1.0 mL/min, and the sample size was 2 μL. The column temperature was 35 ℃, and the detection wavelength was set at 263 nm. Health food was extracted with 60% methanol solution in ultrasonic water bath for 10 min. The extract was filtered through micoron filter, and analyzed by high performance liquid chromatography. Results The results showed that NMN and NAD⁺ exhibited excellent linear relationships, the correlation coefficient (r) was over 0.999 in the range of 10-1000 μg/mL. The method limit of quantitation was 0.50 g/kg. Recoveries were ranged from 95.9% to 98.8%, and relative standard deviations were ranged from 1.19% to 3.05%. Conclusion This method is accurate and suitable to determine NMN and NAD⁺ in health food.

Objective To optimize the production process of casein peptone with yak milk casein as raw material. Methods The combination of alkaline protease and trypsin was used to hydrolyze yak milk casein. On the basis of single factor experiment, according to the principle of Box-Behnken central combination test design, the response surface analysis method of four factors and three levels was adopted, and the degree of hydrolysis was used as the response value. The response surface and contour line were used to obtain the optimal process conditions for the hydrolysis of yak milk casein by the combined enzyme, and then the yak milk casein peptone product was obtained by acid precipitation, neutralization and finally spray drying. Results The results of single factor showed that the degree of hydrolysis of casein increased with the increase of enzyme concentration. When the amount of enzyme added was higher than 2.5%, the degree of hydrolysis increased slowly. With the increase of temperature and pH, the degree of hydrolysis increased first and then decreased. The degree of hydrolysis of yak milk casein reached the maximum when the substrate concentration was 5%, and the substrate concentration would hinder the effect of the enzyme on the cutting site, resulting in a decrease in protein conversion. The results of response surface showed that the degree of hydrolysis was the best when the amount of combined enzyme was 2.6% (alkaline protease:trypsin=4:1), the hydrolysis time was 160 min, the hydrolysis pH was 7.0, the substrate concentration was 5%, and the hydrolysis temperature was 55 °C, which was 23.63%. Conclusion This study optimize the production process of peptone from yak milk casein, and provided support for the further development and utilization of yak milk casein.

Objective To establish a rapid method for the determination of 5 kinds of nucleotides (cytidine-5’-monophosphate, adenosine-5’-monophosphate, uridine-5’-monophosphate, guanosine-5’-monophosphate and inosine-5’-monophosphate) in infant formulas and dairy products is developed based on mixed-mode hydrophilic interaction/ion exchange chromatography-ultraviolet detection (HILIC/IEX-UV). Methods A zwitterionic hydrophilic interaction chromatography column (Alphasil S-Xion) was used, with mobile phase consisting of 5 mmol/L KH₂PO₄ (pH adjusted to 3.0 with H₃PO₄)-acetonitrile (70:30, V:V) to detect nucleotides in infant foods and dairy products. Results The five nucleotides were baseline separated within 10 min, demonstrating efficient chromatographic performance. They exhibited good linearity within the range of 2-50 μg/mL, with limits of detection (LODs) between 0.19 and 0.66 mg/kg, and limits of quantification (LOQs) ranging from 0.62 to 2.19 mg/kg. At spiked levels of 50, 100 and 200 mg/kg, the intraday recoveries ranged from 96.6% to 108.9%, with relative standard deviations (RSDs) of 1.5%-6.3%, while the interday recoveries were between 101.0% and 108.0%, with RSDs of 2.4%-7.3%. Conclusions Compared with the traditional reversed-phase ion-pair chromatography, this method has significant advantages: Effectively reducing the matrix interference, shortening the analysis time, improving the detection efficiency, and especially improving the quantitative accuracy of cytidine-5’-monophosphate. The proposed method is rapid, accurate, and anti-interference, which provides technical support for the efficient analysis of nucleotides in infant formulas and dairy products.

Objective To establish a solution for fungal culturomics in food by comparing the performance of 3 fungal culture media and optimising fungal culturomics techniques. Methods The 24 food samples and 2 proficiency test samples were tested using commonly used fungal culture media for food testing, including potato dextrose agar (PDA), rose Bengal agar, and a novel Pan Fungi medium (PF). The cultured fungi were isolated and identified using matrix assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Results Yeast phase fungi could grow well on all 3 kinds of media, and the colony growth rate, colony morphology size and colony numbers had no significant difference. Filamentous fungi were able to grow well on the 3 kinds of medias, but growth rate and colony morphology were significantly different. There were 12 kinds of fungal species identified in the 24 samples, including 2 kinds of yeast phase fungi and 10 kinds of filamentous fungi. Conclusion With excellent accuracy and stability and self-limited growth of cultured colonies, PF fungal medium is favourable for isolation and identification of single colonies, and can be used as a supplement to the commonly used fungal medium for fungal culturomics studies in food.

Objective To study the difference of meat quality between adult and young Xueduo yaks. Methods Healthy adult and young castrated Xueduo yaks were selected to analyze the composition and content of conventional nutrients, edible meat quality, amino acids, fatty acids, vitamins and minerals in longissimus dorsi muscle. Results The moisture content of adult Xueduo yak meat was 72.89%, which was lower than that of young Xueduo yak meat. The crude protein, crude fat and crude ash contents of adult Xueduo yak meat were 4.99%, 86.67% and 38.54% higher than those of young Xueduo yak meat, respectively. Therefore, adult Xueduo yak meat had higher nutritional value. The edible meat quality of young Xueduo yak meat was excellent, and the color, taste and tenderness were better than those of adult Xueduo yak meat. Both adult and young Xueduo yak meat were high-quality protein sources. The contents of essential amino acids and total amino acids in young Xueduo yak meat were 5.95% and 14.00%, which were significantly higher than those in adult Xueduo yak meat, but adult Xueduo yak meat tastes more delicious. The fatty acid composition of young Xueduo yak meat was slightly better than that of adult Xueduo yak meat. In terms of vitamin and mineral composition and content, vitamin A in young Xueduo yak meat was significantly higher than that in adult Xueduo yak meat. The iodine content of adult Xueduo yak meat was significantly higher than that of young Xueduo yak meat. Conclusion The meat quality of young Xueduo yak is better than that of adult Xueduo yak. The growth cycle of young Xueduo yak is short, which can create higher economic value under limited forage resources. At the same time, it can improve the market competitiveness of yak meat and provide scientific and effective guidance for yak breeding in pastoral areas.

Houttuynia cordata, known as a dual-use plant for both medicine and food, contains various functional components such as flavonoids and polysaccharides. It exhibits multiple bioactivities, including antibacterial, antiviral, anti-inflammatory, antioxidant, anticancer, and immune-regulating effects. The mechanisms underlying its bioactivities are complex and involve the regulation of multiple biological signaling pathways. Currently, Houttuynia cordata is widely used in traditional medicine, functional foods, and cosmetics. Its diverse bioactivities and complex mechanisms suggest a broad application potential. However, further in-depth studies are necessary to elucidate its specific mechanisms of action and ensure safety, thereby promoting its applications in the fields of medicine and health care. This article reviewed the biological activity and mechanism of action of Houttuynia cordata, and summarized the current application status of Houttuynia cordata in medical and healthcare fields, in order to provide reference for further development of Houttuynia cordata.