International audience | An innovative chemometric method was developed to exploit visible and near-infrared (Vis-NIR) spectroscopy to guide food formulation to reach the anticipated and constant quality of final products. First, a total of 671 spectral variables related to the puree quality characteristics were identified by spectral variable selection methods. Second, the concentration profiles from multivariate curve resolution-alternative least squares (MCR-ALS) made it possible to reconstruct the identified spectral variables of formulated purees. Partial least square based on the reconstructed Vis-NIR spectral variables was evidenced to predict the final puree quality, such as a* values (RPD = 3.30), total sugars (RPD = 2.64), titratable acidity (RPD = 2.55) and malic acid (RPD = 2.67), based only on the spectral data of composed puree cultivars. These results open the possibility of controlling puree formulation: a multiparameter optimization of the color and taste of final puree products can be obtained using only the VisNIR spectral data of single-cultivar purees.

Umami peptides, the flavor compounds mainly derived from natural proteins, provide a pleasant taste for humans and exhibit a variety of biological activities, such as antioxidant and lipid-lowering properties. Marine proteins, which serve as excellent sources of umami peptides, have become a focal point of research. This review introduces the research progress on reported marine umami peptides. Firstly, it discusses the structural characteristics of umami peptides and the mechanism behind their formation to create an umami taste. It then presents several commonly used techniques for preparing and regulating umami peptides while summarizing the advantages and disadvantages of each technique. Finally, this review describes the potential application prospects for core technologies within Industry 4.0—such as molecular simulation, artificial intelligence, big data analysis, cloud computing, and blockchain technology—which could bring new opportunities for the development of marine umami peptides.

Given the side effects associated with synthetic antihypertensive drugs, there is a growing need among researchers to investigate angiotensin-converting enzyme (ACE) inhibitory peptides derived from food protein as safer therapeutic alternatives. This study used seabuckthorn (Hippophae rhamnoides L.) seed meal as the raw material, and the protein was extracted by alkaline extraction and acid precipitation. After enzymatic digestion, peptides with molecular weight less than 3 kDa were selected for study. The screened peptide had an IC50 value of 4.358 mg/mL on ACE with a non-competitive inhibition mechanism and good inhibition stability. By employing infrared (IR) analysis, exclusively β-fold and β-helix structures were identified in the hydrolysate, while no other structural motifs were detected. X-ray diffraction revealed that it had an irregular amorphous structure. The peptide contains 17 amino acids that are both highly acidic and hydrophobic, with glutamic acid ranking first in terms of the number of individual amino acids. Compared with the database (NCBI, Uniport), ten peptides with ACE inhibitory activity were detected, and molecular docking showed the mechanism of each peptide inhibiting ACE, FRVAWTEKNDGQRAPLANN, LIISVAYARVAKKLWLCNMIGDVT-TEQY, VIRSRASDGCLEVKEFEDIPP, AGGGG-GGGGGGSRRL, LQPREGPAGGTT-ALREELSLGPEAALDTPPAGP, DDEARINQLFL, FAVSTLTSYDWSDRDDATQGR-KL, RQLSLEGSGLGVEDLKDN, GGGGGGGGGGGGGGGIGGGGGGGGGGGAR, and KEALGEGCFGNRIDRIGD. According to the results, AGGGGGG-GGGGSRRL is more stable in binding to ACE and may have better inhibitory activity. It has been shown that seabuckthorn protein can be an alternative source of ACE inhibitory peptides.

In this study, static and dynamic desorption methods, infrared spectroscopy and, in vitro antioxidant modeling were used to isolate, purify, and investigate the bioactivity of melanoidins extracted from hypoheat-induced Lycium barbarum L. The results showed that melanoidin fractions with molecular weight in the range of 3−10 kDa were the dominant and most valuable fractions. In the purification phase, the optimal purification conditions were: a loading concentration of 4 mg·mL−1, elution volume of 6 BV, and an elution flow rate of 1 mL·min−1. Purified dominant melanoidin fractions (UF3) exhibited typical Maillard reaction (MR) characteristics in FTIR. The storage stability showed that sunlight and heat treatment exacerbated the instability of the purified UF3. At the same time it was relatively stable under dark conditions and incandescent light, with a retention rate of about 90%. After in vitro digestion, the purified UF3 still exhibited good antioxidant activity, and the DPPH scavenging activity and hydroxyl free radical scavenging ability reached more than 60%.

The promising future of natural colors in the food industry aligns with the shift in consumer preference toward healthier food options. These naturally derived ingredients gradually replace their artificial counterparts and find applications in a wide range of food categories, and aquatic products have emerged as one of them. In this work, we introduced the characteristics and extraction of several main types of natural pigments and also explored the positive outcomes of integrating the pigments, such as carotenoids, curcumin, anthocyanins, and betalains, in aquatic product processing and preservation. Their outstanding antioxidant and dyeing properties contribute to the production and storage of various aquatic products. This review aims to provide a comprehensive understanding of the current state of natural pigment applications in aquatic products and to provide inspiration for future research and industry practices.

Serum albumin can bind with a diverse range of small molecules. It could therefore serve a protective or carrier function, and effectively address the issue of anthocyanins' susceptibility to decomposition. The anisotropic effect of the magnetic field (MF) can influence their interaction, thereby playing a distinct role in molecular bonding. In this study, bovine serum albumin (BSA) and cyanidin-3-O-glucoside (C3G) were used as raw materials. The mechanism underlying the formation of BSA-C3G complexes induced by static magnetic field (SMF) was investigated through analyses of secondary structure, functional groups, dipole moment, crystal cell dimensions, and microstructural characteristics. BSA and C3G were treated with 50, 100, 150, and 200 mT, respectively. As the magnetic intensity increased, the secondary structure of the complex changed, the α-spiral content, β-corner content, and irregular curl content decreased, while, the β-folding content increased. The average grain size of the BSA-C3G composite was observed to decrease. Furthermore, alterations in the crystal cell dimensions of the BSA-C3G complex were noted, accompanied by a tendency for the microstructure to become more flattened. This study offers valuable insights into the influence of SMF on the assembly behavior and structural characteristics of proteins and anthocyanins.

Baijiu Daqu, a traditional component in the Baijiu brewing process, serves as both a 'saccharifying fermenting agent' and an 'aroma-producing catalyst', embodying a rich historical legacy. Daqu offers a diverse microorganism environment that is crucial for the fermentation of Baijiu. The distinctive flavor profile, a key attribute of Baijiu, is intricately linked to the microflora present in Daqu. To date, research on Daqu has primarily concentrated on the diversity of microbial communities, microbial interactions, flavor characteristics, and biochemical properties. The functional enzyme system in Daqu serves as a crucial link connecting the flavor of Baijiu with the microbial community of Daqu. However, reviews that particularly focus on the role of enzymes in determining the quality of Daqu have not yet been reported. Thus, here the types and production processes of Daqu are initially summarized. Then, the pathways involved in the production of the major flavor substances in Daqu are elucidated, as well as the role and contribution of different functional enzymes in the formation of Daqu flavor. Finally, the current technologies for improving Daqu flavor through microbial inoculation aree discussed, including the advantages, shortcomings, and bottlenecks of microbial inoculation. The findings gained in this study provide valuable information for the efficient production of high-quality Daqu for the brewing of Baijiu.

The loss of pericarp greenness, wrinkling of the pericarp, and alteration of aroma are indicators of the ripening and senescence of lemons. In this study, lemons were soaked in 100 mg∙L-1 of gibberellin (GA) solutions for 5 min and stored at 14°C for 36 d under three relative humidity (RH) levels of 30%, 60%, and 90%, respectively. The changes in visual appearance, pigment metabolism, pericarpic microstructure, and volatile compounds of lemons during storage were evaluated. The results showed that GA pretreatment inhibited the color transformation from green to yellow of the flavedo and restrained fruit senescence. In addition, RH 90% effectively maintained the structural integrity of the oil gland, waxes, and stomata in the flavedo. GAs + RH 90% treatment maintained the fruit color index (L*, a*, b*, a*/b*, H°, C*) by inhibiting chlorophyll degradation and regulating carotenoid biosynthesis. Green lemons treated with GAs + RH 90% also showed reduced epidermal wrinkling, well-preserved cuticle, and stomatal structure, with a smooth and intact wax layer on the lemon pericarp. In addition, GAs + RH 90% treatment maintained the content of volatile aroma compounds, especially terpene. GAs + RH 90% had a great advantage in maintaining visual quality, delaying the deformation of tissue microstructure, preserving nutritional quality, and improving aroma. Thus, this treatment is potentially applicable for maintaining the storage quality of green lemons and extending their shelf life.

Chilling injury (CI) is a highly common physiological disorder in pomegranates during cold storage. Although several approaches have been investigated to mitigate the CI symptoms among some pomegranate cultivars, the fundamental and crucial environmental factor — the precise storage temperature for the 'Mengzi' cultivation remains unknown. This research evaluated the impact of storage temperatures of 0, 1, 2, 3, and 4 °C on the post-harvest quality of pomegranates. Results indicated that pomegranates stored at 2 °C exhibited the slightest color change and browning index. After storage of 130 d, pomegranates stored at 2 °C exhibited the lower CI index (82.79% reduction) and the lowest decay incidence (24.68% reduction) compared to those stored at 0 °C. The respiratory rate of pomegranates (2 °C) was also evidently suppressed (16.60%), along with a reduction in weight loss (3.46%). Furthermore, pomegranates stored at 2 °C exhibited the lowest activities of polyphenol oxidase (PPO) and peroxidase (POD), accompanied by the highest total phenolic content, which contributed to a reduction in malondialdehyde (MDA) accumulation. Relatively higher concentrations of soluble solids and titratable acid, as well as a higher sensory evaluation, were found in pomegranates stored at 2 °C. Consequently, it was inferred that the optimal temperature maintained cell membrane integrity modulated normal respiratory metabolism, and oxidative balance, and therefore alleviated CI and deterioration. This report can provide the guiding significance for the long-term storage of 'Mengzi' pomegranates under the condition of precise temperature control in phase temperature storage.

Cork taint has devastating effects on the aroma and quality of the wine, which can cause an annual loss of may be up to more than one billion dollars. There are many causes of cork taint, but 2,4,6-trichloroanisole (2,4,6-TCA) is a major contributor, giving the wine a wet-moldy smell. This study provided a comprehensive overview of the occurrence, detection, and control/remediation of 2,4,6-TCA. The occurrence and formation mechanisms of 2,4,6-TCA mainly include microbial O-methylation of chlorophenols and chlorination of anisole. The source of 2,4,6-TCA in wine is the cork or other woodworks, but it is also possible to contaminate wine from the environment. Due to the extremely low odor threshold concentration of 2,4,6-TCA, the effective sample pre-enrichment for instrument identification and quantification is more important. The control/remediation strategies of 2,4,6-TCA mainly include eliminating 2,4,6-TCA in cork and removing 2,4,6-TCA from wine by adsorption. Finally, the challenges and possible future research directions in this research field were discussed and proposed.