Food research international (Ottawa, Ont.)最新文献

Aspergillus flavus not only reduces kiwifruit production but also synthesizes carcinogenic aflatoxins, resulting in a relevant threat to human health. p-Hydroxybenzoic acid (pHBA) is one of the most abundant phenolics in kiwifruit. In this study, pHBA was found to reduce A. flavus mycelial growth by blocking the fungal mitotic exit network (MEN) and cytokinesis and to inhibit the biosynthesis of aflatoxins B₁ and B₂. The application of pHBA promoted the accumulation of endogenous pHBA and induced oxidative stress in A. flavus-infected kiwifruit, resulting in an increase in H₂O₂ content and catalase (CAT) and superoxide dismutase (SOD) activities. Preventive and curative treatments with 5 mM pHBA reduced A. flavus advancement by 46.1% and 68.0%, respectively. Collectively, the antifungal and elicitor properties of pHBA were examined for the first time, revealing new insights into the role of pHBA in the defense response of kiwifruit against A. flavus infection.

Microgels were tailored by combining starches from different sources (corn, potato or phosphated) and anionic polysaccharides (gellan gum or alginate) using ionic gelation. Rheological analysis pointed out a lower consistency index for alginate-based solutions compared to the gellan-based ones and, therefore, this favored the formation of smaller droplets during the atomization process (58.74 ± 1.72 µm vs. 101.38 ± 2.71 µm). Additionally, it was noticed that the starch granule size isdirectly related to the diameter of the particle formed, both for gellan and alginate systems. The combination between starches and anionic gums still promoted an increase in the water holding capacity, probably due to the presence of additional hydrophilic groups from starch. According to the mechanical properties, starch acts differently when combined with alginate or gellan gum, considering it strengthened the biopolymeric network for the alginate-based gels increasing the stress at rupture values (except for potato starch), while it decreasedthe hardness and elasticity for gellan-based gels. Microparticles based on gellan and alginate showed high anthocyanin encapsulation efficiency (EE ≥ 80%) in all systems. In these cases, the addition of starch did not contribute to increasing this property, even though starch granules filled the gel pores. The high EE showed that the studied systems allow the encapsulation of anthocyanin and suggest possible encapsulation of other hydrophilic bioactive compounds, considering the best type of starch for each application.

Suanyu is a famous traditional fermented aquatic food in south China. However, the quality of Suanyu is unstable due to natural fermentation based on the environment. This work screened suitable microbial fermenters (Enterococcus rivorum and Enterococcus lactis) from traditional fermented fish and optimized a suitable fermentation process. Effects of different fermentation (natural and mixed starters fermentation) and thermal treatments (microwave, frying and roasting) on the flavor of Suanyu were investigated. Compared to the natural fermentation group, the TVB-N content (31.5 mg/100 g) was lower, the total acidity (5.12 g/kg) and flavor compounds content were richer in the mixed starters fermentation group (P < 0.05). But there was no significant difference in histamine content (P > 0.05). The roasting treatment group contained higher contents of free amino acids, organic acids, nucleotides and richer key aroma components. The electronic nose was able to distinguish between the differently treated samples. The sensory evaluation result showed that roasted and fried samples had a more acceptable flavor and color. This work will provide a theoretical reference for the standardized production of Suanyu and the development of pre-cooked products.

Hongqu rice wine, a famous traditional fermented alcoholic beverage, is brewed with traditional Hongqu (mainly including Gutian Qu and Wuyi Qu). This study aimed to compare the microbial communities and metabolic profiles in the traditional brewing of Hongqu rice wines fermented with Gutian Qu and Wuyi Qu. Compared with Hongqu rice wine fermented with Wuyi Qu (WY), Hongqu rice wine fermented with Gutian Qu (GT) exhibited higher levels of biogenic amines. The composition of volatile flavor components of Hongqu rice wine brewed by different fermentation starters (Gutian Qu and Wuyi Qu) was obviously different. Among them, ethyl acetate, isobutanol, 3-methylbutan-1-ol, ethyl decanoate, ethyl palmitate, ethyl oleate, nonanoic acid, 4-ethylguaiacol, 5-pentyldihydro-2(3H)-furanone, ethyl acetate, n-decanoic acid etc. were identified as the characteristic aroma-active compounds between GT and WY. Microbiome analysis based on high-throughput sequencing of full-length 16S rDNA/ITS-5.8S rDNA amplicons revealed that Lactococcus, Leuconostoc, Pseudomonas, Serratia, Enterobacter, Weissella, Saccharomyces, Monascus and Candida were the predominant microbial genera during the traditional production of GT, while Lactococcus, Lactobacillus, Leuconostoc, Enterobacter, Kozakia, Weissella, Klebsiella, Cronobacter, Saccharomyces, Millerozyma, Monascus, Talaromyces and Meyerozyma were the predominant microbial genera in the traditional fermentation of WY. Correlation analysis revealed that Lactobacillus showed significant positive correlations with most of the characteristic volatile flavor components and biogenic amines. Furthermore, bioinformatical analysis based on PICRUSt revealed that microbial enzymes related to biogenic amines synthesis were more abundant in GT than those in WY, and the enzymes responsible for the degradation of biogenic amines were less abundant in GT than those in WY. Collectively, this study provides important scientific data for enhancing the flavor quality of Hongqu rice wine, and lays a solid foundation for the healthy and sustainable development of Hongqu rice wine industry.

Rebaudioside A, a sweet-tasting steviol glycoside, is known to degrade in food products during storage and thought to contribute to flavor instability. The impact of rebaudioside A degradation compounds on flavor perception was investigated. Sensory descriptive analysis indicated rebaudioside A degradation compounds, at concentrations below detection thresholds, modified the perception of taste, somatosensorial, and retronasal aroma attributes of a strawberry-flavored model beverage. Gas chromatography/mass spectrometry analysis and orthonasal sensory tetrad tests further indicated the addition of the degradation compounds did not significantly alter the volatile aroma composition or orthonasal perception, respectively. Altogether, subthreshold unimodal and cross-modal integration of multisensory percepts were supported to impact the flavor performance of rebaudioside A.

The functional activity of dietary astaxanthin is closely related to its absorption, and the absorption of dietary carotenoids mainly mediated by transmembrane transport protein (TTP) has become the mainstream research direction in recent years. However, the main TTP mediating astaxanthin absorption and its potential mechanisms are still unclear. Hence, based on the preliminary screening results, this study aims to elucidate the role of cluster-determinant 36 (CD36) mediating astaxanthin absorption from the perspective of expression levels through in vitro cell model, in situ single-pass intestinal perfusion model and in vivo mice model. The results showed that astaxanthin uptake was significantly increased by 45.13% in CD36 overexpressing cells and decreased by 20.92% in the case of sulfo-N-succinimidyl oleate (SSO) inhibition. A similar trend also appeared in the duodenum and jejunum by in situ model. Moreover, astaxanthin uptake in the small intestine of CD36 knockout mice was significantly reduced by 88.22%. Furthermore, the inhibition or knockout of CD36 suppressed the expression of other transporters (SR-BI and NPC1L1). Interestingly, CD36 was also involved in the downstream secretion pathway, which is manifested by interfering with the expression of related proteins (ERK1/2, MTP, ApoB48, and ApoAI). Therefore, these results indicate the important role of CD36 in astaxanthin transmembrane transport for the first time, providing vital exploration way for the absorption of dietary fat-soluble substances.

This study evaluated the use of a semi-continuous high-pressure hydrothermal process for the recovery of value-added products from pitaya peel. The process was carried out at 15 MPa, a water flow rate of 2 mL/min, a solvent-to-feed ratio of 60 g water/g pitaya peel, and temperatures ranging from 40 to 210 °C. The results show that extraction temperatures (between 40 and 80 °C) promoted the recovery of betacyanin (1.52 mg/g), malic acid (25.6 mg/g), and citric acid (25.98 mg/g). The major phenolic compounds obtained were p-coumaric acid (144.63 ± 0.42 µg/g), protocatechuic acid (91.43 ± 0.32 µg/g), and piperonylic acid (74.2 ± 0.31 µg/g). The hydrolysis temperatures (between 150 and 210 °C) could produce sugars (18.09 mg/g). However, the hydrolysis process at temperatures above 180 °C generated Maillard reaction products, which increased the total phenolic compounds and antioxidant activity of the hydrolysates. Finally, the use of semi-continuous high-pressure hydrothermal process can be a sustainable and promising approach for the recovery of value-added compounds from pitaya peel, advocating a circular economy approach in the agri-food industry.

The increase in world population has generated a higher demand for quality proteins, increasing the production in meat industry but also the generation of thousands of tons of by-products, with a negative economic and environmental impact. The valorisation of slaughterhouse by-products by giving by-products a new use as food ingredient is one of the best strategies to add value while reducing environmental damage. Flavour is one of the most influential parameters in the purchasing decision of consumers, and in meat products it is mostly influenced by the content in free amino acids and nucleotides. In this study, the potential of 4 pork organs (liver, kidney, lung, and brain) as a source of flavour-related substances was investigated. Liver proved to be the organ showing the highest content of free and total amino acids related to taste, while kidney was the organ with the highest content of umami nucleotides. The results of the Taste Activity Value indicated that umami, sweet, and bittersweet amino acids are main responsible for the taste of the organs. On the other hand, the synergy between amino acids and nucleotides in relation with umami taste was determined, showing liver and kidney the best values in Equivalent Umami Content. In addition, the antioxidant activity of the organs was determined, and liver and kidney showed the highest antioxidant activity in all assays (p < 0.05). In conclusion, pork organs, especially liver and kidney, may be good candidates to be used as raw materials to produce functional flavouring ingredients.

Photolytic transformation of aspartame - a widely used artificial sweetener - under the simulated sunlight was studied for the first time. The experiments were conducted in pH range of 2.5 - 7.0 and in eight soft drinks available in the market. The highest degradation rate in the tested buffered solutions was observed under the neutral pH conditions. Irradiation of the soft drinks resulted in significantly (up to tenfold) faster degradation of aspartame, regardless of its initial concentration in the beverage. Such considerable acceleration of decomposition, not reported for aspartame so far, was ascribed to influence of the co-occurring ingredients, which can act as the photosensitizers. These findings indicate that some formulations may be particularly unfavorable in the context of aspartame photostability. Qualitative analysis of the studied processes revealed formation of six phototransformation products including three previously not described. In silico estimation of toxicity showed that some of the identified photoproducts, including the novel phenolic derivatives, may be more harmful than the parent compound. Taking into account relatively extensive formation of those products in the soft drinks, such finding may be particularly important from the food safety point of view.