Insights into the enhancement of food flavor perception:strategies,mechanism and emulsion applications

The core drivers of the modern food industry are meeting consumer demand for tasty and healthy foods.The application of food flavor perception enhancement can help to achieve the goals of salt-and sugar-reduction,without compromising the sensory quality of the original food,and this has attracted increasing research attention.The analysis of bibliometric results from 2002 to 2022 reveals that present flavor perception enhancement strategies(changing ingredient formulations,adding salt/sugar substitutes,emulsion delivery systems)are mainly carry out based on sweetness,saltiness and umami.Emulsion systems is becoming a novel research foci and development trends of international food flavor perception-enhancement research.The structured design of food emulsions,by using interface engineering technology,can effectively control,or enhance the release of flavor substances.Thus,this review systematically summarizes strategies,the application of emulsion systems and the mechanisms of action of food flavor perception-enhancement technologies,based on odor-taste cross-modal interaction(OTCMI),to provide insights into the further structural design and application of emulsion systems in this field.

Structure elucidation and in vitro rat intestinal fermentation properties of a novel sulfated glucogalactan from Porphyra haitanensis

This study was to investigate the structure and rat fecal microbial fermentation properties of a polysaccharide fraction(PHP2)isolated from the red marine alga Porphyra haitanensis.PHP2 was characterized as a sulfated glucogalactan,with a hypothetical backbone structure of→4)Gα(1→6)G4 Sβ(1→4)Glc(1→and a side chain of Man(1→6)Glc.PHP2 had an irregular spherical chain conformation.The 16 S r RNA sequence analysis revealed that PHP2 modulated the rat fecal micro-flora composition,with a similar effect to inulin,changing the dominant genus(Lactobacillus and Escherichia-Shigella)and promoting the growth of organisms that degrade sulfur-containing polysaccharides,such as Desulfovibrio,Ruminococcaceae_UCG-005,and Ruminococcus_2.PHP2 can promote production of acetic,propionic and butyric acid by rat fecal micro-flora.Prediction of metabolic function suggested that PHP2 could modulate cholesterol metabolism.The sulfated glucogalactan fermentation behavior may be associated with its monosaccharide composition,chain branching and chain conformation.PHP2 appeared to have considerable potential as functional food,and was associated with sulfur-containing polysaccharides in general.

Effect of polysaccharide fractions from Fortunella margarita on the fecal microbiota of mice and SCFA production in vitro

Fortunella margarita polysaccharides(FMPS)are composed of 4 polysaccharide fragments,namely mannogalactoglucan,galactoglucan,glucan and arabinoglucan.This study investigated the in vitro fermentation of FMPS fractions and their effect on the fecal microbiota of mice and short chain fatty acids(SCFAs)production.The results showed that the structure of the fecal microbiota was changed after FMPS fermentation.At the phylum level,the polysaccharide fractions reduced the relative abundance of Bacteroidetes compared with the inulin group.At the genus level,the polysaccharide fractions increased the abundance of Lactobacillus,and decreased the abundance of Granulicatella,Proteus and Rummeliibacillus.Polysaccharide fractions could promote the proliferation of beneficial bacteria(Lactobacillus),and decreased harmful bacteria(Granulicatella,Proteus,Rummeliibacillus and Serratia).Furthermore,there was a significant distinction in the genus level flora processed by different polysaccharide fractions,especially mannogalactoglucan.Polysaccharide fractions showed potential prebiotic effects,with mannogalactoglucan,in particular,promoting proliferation of SCFA-producing bacteria.SCFAs were regulated by monosaccharide composition,molecular weight of the FMPS fractions,and the composition of the fecal bacteria.Polysaccharide fractions could modulate metabolic function of the fecal microbiota,altering the levels of SCFAs.These results suggested that FMPS are important functional components in gut health,especially mannogalactoglucan.

Generalized inverses of tensors via a general product of tensors

We define the {i}-inverse （i = 1,2, 5） and group inverse of tensors based on a general product of tensors. We explore properties of the generalized inverses of tensors on solving tensor equations and computing formulas of block tensors. We use the {1}-inverse of tensors to give the solutions of a multilinear system represented by tensors. The representations for the {1}-inverse and group inverse of some block tensors are established.

Group invertible block matrices

Let M =（ABCD）（A and D are square） be a 2 × 2 block matrixgeneralized Schur complement of M. We give the representations and the group invertibility of M under each of the following conditions： （1） S = 0; （2） S is group invertible and CAπB = 0, where Aπ= I - AA#. And the second result generalizes a result of C. Bu et al. [Appl. Math. Comput., 2009, 215： 132-139].

The optimization of ultrasonic-microwave assisted synergistic extraction of Lotus plumule extract rich in flavonoids and its hypoglycemic activity

Lotus(Nelumbo nucifera Gaertn),a kind of perennial aquatic plant,is widely cultivated and consumed by people in Asian countries.Lotus plumule flavonoids(LPF)have been recognized as a hypoglycemic agent.LPF was optimally obtained using novel ultrasonic-microwave assisted synergistic extraction(UMSE)method by response surface methodology(RSM)on the basis of the results of single-factor experiments.Furthermore,the hypoglycemic activity of LPF was investigated by measuring the body weight,fasting blood glucose(FBG)level,and oral glucose tolerance test(OGTT)and analyzing the physiological indexes in streptozotocin-diabetic mice model.The optimum extraction conditions consisted of microwave power 355 W,ultrasonic power 423 W,extraction time 15 min,solid-liquid ratio 1:40,ultrasound/interval time 1/0,and ethanol concentration 70%with the maximum LPF yield of 2.62%.LPF supplementation significantly decreased the body weight,FBG,OGTT,serum total cholesterol(TC),serum total triglycerides(TG),and insulin levels,indicating the antidiabetic activity of LPF.This research verified that the UMSE technique was highly efficient to extract LPF to the maximum extent and the flavonoids from L.plumule exhibited hypoglycemic activity,which showed broad development and application prospects.