Comparison of soluble dietary fibers from various quinoa microgreens: Structural characteristics and bioactive properties

Structural Characteristics, Gelling Properties, In Vitro Antioxidant Activity and Immunomodulatory Effects of Rhamnogalacturonan-I Rich Pectic Polysaccharides Alkaline-Extracted from Wax Apple (Syzygium samarangense)

To upgrade the utilization of Syzygium samarangense in food industries, the key biological component, i.e., polysaccharide, was extracted from the fruit by alkaline treatment, and its structural characteristics, physicochemical properties, gelling properties and biological activities were investigated. The findings demonstrated that the alkaline-extracted S. samarangense polysaccharide (SSP-AK) predominantly exists as a pectic polysaccharide with a high rhamnogalacturonan-I domain. The monosaccharide composition primarily includes rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, and arabinose. The molecular weight distribution of SSP-AK was characterized by two peaks, with fraction 1 exhibiting a high molecular weight of 7658 kDa and fraction 2 exhibiting a molecular weight of 345.3 kDa. Meanwhile, SSP-AK exhibited excellent rheological behavior and gelling properties upon Ca2+-induced gelation, which may be related to its relatively low degree of esterification of 41.3%. Further studies revealed that higher concentrations of pectin and Ca2+ led to the formation of stronger gels. The SSP-AK gels exhibited superior rheological properties, increased hardness, enhanced water-holding capacity, and a more compact network structure than the other gels. Moreover, SSP-AK exhibited significant in vitro antioxidant activity and immunomodulatory effects, including significantly enhancing the DPPH and ABTS radical-scavenging abilities and production of NO, IL-6, and TNF-α in RAW264.7 cell models. This study enhances the understanding of S. samarangense cell wall polysaccharides and may facilitate their application in the development of functional and health-oriented food products.

Influence of the Nutritional Composition of Quinoa (Chenopodium quinoa Willd.) on the Sensory Quality of Cooked Quinoa

In order to explore the effect of the content of nutritional components of quinoa on its sensory quality, 22 quinoa varieties were collected from 11 major quinoa-producing areas at home and abroad as experimental materials. The contents of total starch, protein, fat, crude fiber, ash, VB1, VB2, moisture and saponin were determined, and the sensory evaluation and electronic tongue analysis of cooked quinoa were carried out. The sensory quality of quinoa was comprehensively evaluated by correlation analysis, principal component analysis and cluster analysis. The results show that the contents of various nutritional components had significant effects on the sensory quality of quinoa (p < 0.05). Quinoa with high starch, high VB1, moderate fat, moderate moisture, low protein, low crude fiber, low ash and low saponin content had better cooking quality and was more popular. Electronic tongue analysis showed that the sweet response value of cooked quinoa was the highest, followed by the bitter response value. No. 12 and No. 9 cooked quinoa samples had the best comprehensive taste, the highest sensory score and the best cooking quality. This study preliminarily clarified the relationship between the content of different nutritional components in quinoa and its sensory quality, which could provide reference for the selection of raw materials and breeding of quinoa varieties for different processing purposes.

Novel mangosteen peel prebiotic with cardamom oil supports probiotic growth and preservation of rice sausage

Mangosteen peel (MP) is being studied for its prebiotic potential due to its high dietary fiber and bioactive compounds. This research evaluated MP combined with cardamom oil (CM) at 300 µl, examining its effects on probiotic growth and antibacterial activity against foodborne pathogens (Escherichia coli, Salmonella Typhimurium, Listeria monocytogenes, Staphylococcus aureus, and Clostridium perfringens). Additionally, CM-treated MP was tested to extend the shelf life of rice sausage. CM-treated MP showed significant dietary fiber (58%) and bioactive compounds, including total phenolics (18.5 mgGAE/100 g), flavonoids (50.5 mgQE/100 g), and strong antioxidant activity (IC50 of ABTS: 8.3 µg/mL, DPPH: 9.4 µg/mL). It promoted probiotic growth, lowered pH, and inhibited pathogens. The shelf life of rice sausage extended from 7 to 21 days at 4 °C. The color of the treated sausage showed the highest red-yellow after fermenting for 21 days, with maximum a* (10.49 ± 0.51) and b* (22.40 ± 0.97), compared to the control (a* ~ 3.88 ± 0.35, b* ~ 11.66 ± 1.67). It also increased lactic acid bacteria and prevented pathogen growth. These findings suggest that CM-treated MP shows promise as a prebiotic for enhancing the safety of fermented foods and could be particularly beneficial in the fermented rice sausage industry due to its low production cost. MP, produced from waste, is an inexpensive ingredient that is easy to incorporate into rice sausage production. This enhances the product's value, provides prebiotic benefits, and boosts both marketability and consumer interest in healthy food options.

Quinoa Polysaccharides: Extraction, Purification, Structure, Functional Properties, and Applications in Food Science and Health

Quinoa polysaccharides have attracted significant research interest in recent years due to their diverse biological activities, including antiviral, anti-inflammatory, antioxidant, and immunoregulatory properties. These attributes align with the growing global demand for natural, functional food ingredients, positioning quinoa polysaccharides as a valuable resource in food science and technology. This review presents an overview of the various bioactivities of quinoa polysaccharides, critically evaluates the methods used for their extraction and purification, describes their structural characteristics, and discusses their practical applications across multiple areas within the food industry, including food additives, meat products, health foods, and innovative food packaging. This study examines the relationship between the preparation methods and the structural characteristics of quinoa polysaccharides, as well as their versatile applications in the food industry, such as improving product quality and shelf life, enhancing nutritional value and antioxidant activity, and providing health benefits in functional foods. This review also emphasizes the need for further research on the emulsification and gelation properties of quinoa polysaccharides and highlights their significant market potential, driven by their diverse functional properties. From our perspective, quinoa polysaccharides, with their wide range of functional and health benefits, hold a promising future in the food and health industries, driven by technological advancements and consumer demands.

Pectic polysaccharides from Tartary buckwheat sprouts: Effects of ultrasound-assisted Fenton treatment and mild alkali treatment on their physicochemical characteristics and biological functions

Buckwheat sprouts are rich in pectic polysaccharides, which possess numerous health-improving benefits. However, the precise structure-activity relationship of pectic polysaccharides from Tartary buckwheat sprouts (TP) is still scant, which ultimately restricts their applications in the food industry. Hence, both ultrasound-assisted Fenton treatment (UAFT) and mild alkali treatment (MATT) were utilized for the modification of TP, and then the effects of physicochemical characteristics of original and modified TPs on their bioactivities were assessed. Our findings reveled that the UAFT treatment could precisely reduce TP's molecular weight, with the levels decreased from 8.191 × 104 Da to 0.957 × 104 Da. Meanwhile, the MATT treatment could precisely reduce TP's esterification degree, with the values decreased from 28.04 % to 4.72 %. Nevertheless, both UAFT and MATT treatments had limited effects on the backbone and branched chain of TP. Moreover, our findings unveiled that the UAFT treatment could notably promote TP's antioxidant, antiglycation, and immunostimulatory effects, while remarkedly reduce TP's anti-hyperlipidemic effect, which were probably owing to that the UAFT treatment obviously reduced TP's molecular weight. Additionally, the MATT treatment could also promote TP's immunostimulatory effect, which was probably attributed to that the MATT treatment significantly decreased TP's esterification degree. Interestingly, the MATT treatment could regulate TP's antioxidant and antiglycation effects, which was probably attributed to that the MATT treatment simultaneously reduced its esterification degree and bound phenolics. Our findings are conducive to understanding TP's structure-activity relationship, and can afford a scientific theoretical basis for the development of functional or healthy products based on TPs. Besides, the UAFT treatment can be a promising approach for the modification of TP to improve its biological functions.

Potential structure-function relationships of pectic polysaccharides from quinoa microgreens: Impact of various esterification degrees

Pectic polysaccharides are one of the most vital functional ingredients in quinoa microgreens, which exhibit numerous health-promoting benefits. Nevertheless, the detailed information about the structure-function relationships of pectic polysaccharides from quinoa microgreens (QMP) remains unknown, thereby largely restricting their applications as functional foods or fortified ingredients. Therefore, to unveil the possible structure-function relationships of QMP, the mild alkali de-esterification was utilized to modify QMP, and then the correlations of esterification degrees of native and modified QMPs to their biological functions were systematically investigated. The results showed that the modified QMPs with different esterification degrees were successfully prepared by the mild alkali treatment, and the primary chemical structure (e.g., compositional monosaccharides and glycosidic linkages) of the native QMP was overall stable after the de-esterified modification. Furthermore, the results revealed that the antioxidant capacity, antiglycation effect, prebiotic potential, and immunostimulatory activity of the native QMP were negatively correlated to its esterification degree. In addition, both native and modified QMPs exerted immunostimulatory effects through activating the TLR4/NF-κB signaling pathway. These results are conducive to unveiling the precise structure-function relationships of QMP, and can also promote its applications as functional foods or fortified ingredients.

Impacts of ultrasound-assisted Fenton degradation and alkaline de-esterification on structural properties and biological effects of pectic polysaccharides from Tartary buckwheat leaves

Tartary buckwheat (Fagopyrum tataricum (L.) Gaertn) leaf has abundant rhamnogalacturonan-I enriched pectic polysaccharides, which exert various health-promoting effects. Nevertheless, the potential relationship between the chemical structure and the biological function of pectic polysaccharides from Tartary buckwheat leaves (TBP) remains unclear. Therefore, to bridge the gap between the chemical structure and the biological function of TBP, the impacts of ultrasound-assisted Fenton degradation (UFD) and mild alkaline de-esterification (MAD) on structural properties and biological effects of TBP were systematically studied. Compared with the native TBP (molecular mass, 9.537 × 104 Da), the molecular masses of degraded TBPs (TBP-MMW, 4.811 × 104 Da; TBP-LMW, 2.101 × 104 Da) were significantly reduced by the UFD modification, while their primary chemical structures were overall stable. Besides, compared with the native TBP (esterification degree, 22.73 %), the esterification degrees of de-esterified TBPs (TBP-MDE, 14.27 %; TBP-LDE, 6.59 %) were notably reduced by the MAD modification, while their primary chemical structures were also overall stable. Furthermore, the results revealed that both UFD and MAD modifications could significantly improve the antioxidant, antiglycation, and immunostimulatory effects of TBP. Indeed, TBP's biological effects were negatively correlated to its molecular mass and esterification degree, while positively linked to its free uronic acids. The findings demonstrate that both UFD and MAD modifications are promising techniques for the structural modification of TBP, which can remarkedly promote its biological effects. Besides, the present results are conducive to better understanding TBP's structure-bioactivity relationship.

Efficient and Selective Extraction of Rhamnogalacturonan-I-Enriched Pectic Polysaccharides from Tartary Buckwheat Leaves Using Deep-Eutectic-Solvent-Based Techniques

Tartary buckwheat green leaves are considered to be among the most important by-products in the buckwheat industry. Although Tartary buckwheat green leaves are abundant in pectic polysaccharides, their potential applications in the food industry are quite scarce. Therefore, to promote their potential applications as functional or fortified food ingredients, both deep-eutectic-solvent-assisted extraction (DESE) and high-pressure-assisted deep eutectic solvent extraction (HPDEE) were used to efficiently and selectively extract pectic polysaccharides from Tartary buckwheat green leaves (TBP). The results revealed that both the DESE and HPDEE techniques not only improved the extraction efficiency of TBP but also regulated its structural properties and beneficial effects. The primary chemical structures of TBP extracted using different methods were stable overall, mainly consisting of homogalacturonan and rhamnogalacturonan-I (RG-I) pectic regions. However, both the DESE and HPDEE methods could selectively extract RG-I-enriched TBP, and the proportion of the RG-I pectic region in TBP obviously improved. Additionally, both the DESE and HPDEE methods could improve the antioxidant and anti-glycosylation effects of TBP by increasing its proportion of free uronic acids and content of bound polyphenolics and reducing its molecular weight. Moreover, both the DESE and HPDEE methods could partially intensify the immunostimulatory effect of TBP by increasing its proportion of the RG-I pectic region. These findings suggest that DES-based extraction techniques, especially the HPDEE method, can be promising techniques for the efficient and selective extraction of RG-I-enriched TBP.