Processing of Whole Kernel Tapioca Pearl and Milk Tea BOBA of Fresh Highland Barley: Optimization of Processing Parameters and Quality Evaluation.

Fresh highland barley is difficult to store, leading to a lack of commercial products. To address these problems, the research investigated the effect of different heat treatments (steaming , microwaving , baking , and cooking ) on the quality of fresh highland barley, and used pretreated fresh highland barley as material, combined with the milk tea market, to design and optimize the preparation process of fresh highland barley tapioca pearl and milk tea BOBA. The results showed that the different heat treatments reduced the content of ash and starch significantly, and SFB and MFB decreased the digestibility of fresh highland barley (P < 0.05). In particular, SFB had a significantly higher overall score for fresh barley than the other treatments, with the highest sensory evaluation for aroma, elasticity, and the overall taste of the grain, and the eGI value was the lowest (58.64). The optimal preparation process of fresh highland barley tapioca pearl and milk tea BOBA was designed and optimized by the L9(34) orthogonal test. The optimal tapioca pearl formula contained the following: apioca starch content of 36%, cooking time of 2.5 min, and erythritol stevia content of 1.5%. The optimal milk tea BOBA formula contained the following: sodium alginate content of 1.3%, erythritol stevia content of 0.6%, and calcium lactate content of 2.2%. This not only improves the comprehensive utilization rate of fresh highland barley, but also provides the accessory food, ensuring a lower eGI and increasing the healthiness and diversity of milk tea.

Effects of Heat-Moisture Treatment Whole Tartary Buckwheat Flour on Processing Characteristics, Organoleptic Quality, and Flavor of Noodles.

The effects of heat-moisture treatment whole tartary buckwheat flour (HTBF) with different contents on the pasting properties and hydration characteristics of tartary buckwheat noodle mix flour (TBMF), dough moisture distribution, cooking properties, texture properties, and flavor of noodles were studied. The results showed that the optimal additional amount of HTBF is determined to be 40%. The peak viscosity, trough viscosity, breakdown value, and final viscosity decreased significantly, and the optimal cooking time of the noodles decreased with increasing HTBF. Compared with the sample without HTBF, HTBF addition increased the water absorption of the sample and decreased its water solubility. When the amount of HTBF >30%, the content of strongly bound water in dough increased significantly; at HTBF >40%, the water absorption and cooking loss of noodles increased rapidly, and the hardness of noodles was decreased; and with HMBF addition at 60%, the chewiness, resilience, and elasticity decreased. Moreover, HMBF addition reduced the relative content of volatile alkanes, while increasing the amount of volatile alcohols. HTBF addition also elevated the content of slow-digesting starch (SDS) and resistant starch (RS) in noodles, providing noodles with better health benefits in preventing chronic diseases. These results proved the possibility of applying heat-moisture treatment grains to noodles, and they provide a theoretical basis for the research and development of staple foods with a hypoglycemic index.

Structure Characterization and Potential Probiotic Effects of Sorghum and Oat Resistant Dextrins.

Resistant dextrins (RDs) were prepared from sorghum and oat starches to determine their molecular structure, physicochemical properties, digestibility and prebiotics effect in vitro. The results showed that the particle size of sorghum resistant dextrin (SRD) and oat resistant dextrin (ORD) was significantly smaller than their respective starches. They formed a block structure, and lost the original A-type structure. In addition, SRD and ORD had good thermal stability, solubility (>90%) and enzymatic hydrolysis resistance (digestibility < 5%). The potential probiotic effects of ORD and SRD were studied by measurement of their promoting effects on the growth of Lactiplantibacillus plantarum, Lactobacillus acidophilus and Lactobacillus delbrueckii. For Lactiplantibacillus plantarum and Lactobacillus acidophilus, the promoting effect of ORD was the best (p < 0.05), and the counts increased by 8.89 and 8.74 log CFU/mL, respectively, compared with the control. For Lactobacillus delbrueckii, SRD was most effective, increasing the counts by 8.72 log CFU/mL compared with the control. These characteristics make SRD and ORD suitable for use as soluble dietary fiber and prebiotics in beverages and the excipients of low-glycemic-index products.

Physicochemical characteristics and in vitro digestibility of starches from colored quinoa (Chenopodium quinoa) varieties.

The quinoa flour processing is mostly subject to the properties of starch. Starches from four colored quinoa varieties, including white quinoa (QS-W), yellow quinoa (QS-Y), red (QS-R), and black (QS-B), were compared with respect to their physicochemical properties and in vitro digestibility. Results indicated that QS-B exhibited the highest content of amylose (8.14%) (p < 0.05). All starch samples exhibited as irregular sphere with a particle size less than 3 µm. Results of the FT-IR and X-ray showed that the short-range order of the four quinoa starches exhibited no significant difference; all starches showed a typical A-type diffractrometric pattern and was not affected by seed color, and QS-Y had the highest relative crystallinity (34.3%) (p < 0.05). In addition, QS-W reflected the highest solubility (6.32%) and QS-Y showed the highest swelling power (19.45 g/g) (p < 0.05). QS-Y also presented a higher ΔH value (11.46 J/g) (p < 0.05), while QS-R peak temperature and peak G' were the lowest. Besides, QS-B had the highest slow-digestible starch (SDS) and resistant starch (RS) content, while the lowest estimated glycemic index (eGI) value (p < 0.05). Also, there was a negative correlation between hydrolysis rates and amylose content of quinoa starch. PRACTICAL APPLICATION: Due to the low gelatinization temperature of quinoa starch, it can be used to both produce and improve instant and fast food products. Quinoa starch particles are small, and Pickering emulsions and additives have potential application values. Red quinoa contains easily digestible starch, which can be a good food choice for infants and the elderly, while white quinoa starch has less swelling power and can be used in noodle products. The results of this study can help to underpin the study of quinoa nonstarch components versus starch component.

Effect of Heat-Moisture Treatments on Digestibility and Physicochemical Property of Whole Quinoa Flour.

The starch digestion processing of whole grain foods is associated with its health benefits in improving insulin resistance. This study modified the digestibility of whole quinoa flour (WQ) via heat-moisture treatment (HMT), HMT combined with pullulanase (HMT+P), HMT combined with microwave (HMT+M), and HMT combined with citric acids (HMT+A), respectively. Results showed that all the treatments significantly increased (p < 0.05) the total dietary fiber (TDF) content, amylose content, and resistant starch (RS) content, however, significantly decreased (p < 0.05) the amylopectin content and rapidly digestible starch (RDS) content of WQ. HMT+P brought the highest TDF content (15.3%), amylose content (31.24%), and RS content (15.71%), and the lowest amylopecyin content (30.02%) and RDS content (23.65%). HMT+M brought the highest slowly digestible starch (SDS) content (25.09%). The estimated glycemic index (eGI) was respectively reduced from 74.36 to 70.59, 65.87, 69.79, and 69.12 by HMT, HMT+P, HMT+M, and HMT+A. Moreover, a significant and consistent reduction in the heat enthalpy (ΔH) of WQ was observed (p < 0.05), after four treatments. All these effects were caused by changes in the starch structure, as evidenced by the observed conjunction of protein and starch by a confocal laser scanning microscope (CLSM), the decrease in relative crystallinity, and transformation of starch crystal.

Development of weaning food with prebiotic effects based on roasted or extruded quinoa and millet flour.

Weaning is the gradual process of introducing solids or semisolid foods into an infant's diet, in order to ensure their healthy growth. This study developed two kinds of formula weaning food based on roasted or extruded quinoa and millet flour, and evaluated their quality. A fructo-oligosaccharide (FOS)/galacto-oligosaccharide (GOS) mix was added to provide the prebiotic potential. The protein contents of the roasted quinoa-millet complementary food (RQMCF) and extruded quinoa-millet complementary food (EQMCF) were 16.7% and 17.74% higher, respectively, than that of commercial millet complementary food (CMCF). Both RQMCF and EQMCF provided sufficient levels of energy and minerals. Extrusion provided the foods with a lower viscosity, and higher solubility and water absorption ability than roasting. In vitro digestion results showed that EQMCF exhibited the highest starch and protein digestibility (89.76% and 88.72%, respectively) followed by RQMCF (87.75% and 86.63%) and CMCF (83.35% and 81.54%). The digestas of RQMCF and EQMCF after in vitro digestion exhibited prebiotic effects by promoting the growth of the probiotics (Lactobacillus plantarum and Lactobacillus delbrueckii). These results will contribute to developing complementary weaning foods for infants. PRACTICAL APPLICATION: This study has shown that extrusion is an efficient and stable processing method for producing infant complementary foods with low density, balanced nutrition, and high levels of starch and protein digestibility. Extruded quinoa-millet prebiotic complementary food can also promote the proliferation of probiotics. This will provide a new direction for developing novel infant formula weaning foods.

Effects of ultraviolet-C light-emitting diodes at 275 nm on inactivation of Alicyclobacillusacidoterrestris vegetative cells and its spores as well as the quality attributes of orange juice.

Alicyclobacillus acidoterrestris is a thermoacidophilic, spore-forming bacillus. A. acidoterrestris and its spores can survive in pasteurized juices and cause microbial spoilage. In this work, the effects of ultraviolet-C light-emitting diodes at 275 nm on the inactivation of A. acidoterrestris vegetative cells and its spores in commercial pasteurized orange juice were studied. Meanwhile, the effects of ultraviolet-C light-emitting diodes on the quality attributes of the orange juice were also investigated. The quantities of A. acidoterrestris vegetative cells and its spores inoculated in orange juice were reduced by 6.04 and 2.49 log10 CFU/mL after ultraviolet-C light-emitting diode treatment at 220 mJ/cm2, respectively. The Weibull and Weibull plus tail models were satisfactorily fitted to estimate the reductions of A. acidoterrestris vegetative cells and its spores in orange juice, respectively. Physicochemical properties (pH, titratable acidity, total soluble solids, and clarity) of orange juice did not change significantly after exposure to ultraviolet-C light-emitting diodes. However, the total phenolic content of orange juice decreased with increasing fluence. In addition, ultraviolet-C light-emitting diode treatment at a higher fluence led to a noticeable color difference. These results indicate that ultraviolet-C light-emitting diode treatment has a potential application in the juice processing industry.

Comparative study of thermal processing on the physicochemical properties and prebiotic effects of the oat ß-glucan by in vitro human fecal microbiota fermentation.

This study aimed to compare the prebiotic effects of oat ß-glucan between steaming and microwave processing by high-throughput sequencing. The results showed that microwave-processed oat ß-glucan with lower average molecular weight (Mw) exhibited a more significant effect in promoting Lactobacillus and Bifidobacterium compared with steaming processed oat ß-glucan with higher Mw at the genus level. The overall microbial composition structure results indicated that the relative abundance of Escherichia-Shigella, Lactobacillus, Enterococcus, and Dialister exhibited significant differences between the samples (p < 0.05). Additionally, the short-chain fatty acid in microwave-processed oat ß-glucan fermentation slurries significantly increased (p < 0.05), and more butyrate was produced from microwave-processed oat ß-glucan, which may be attributed to the higher levels of Blautia and Dialister as butyrate-producers. These results suggest that microwave processing contributed to the degradation of oat ß-glucan and enhanced its prebiotic function.

Effects of atmospheric pressure plasma jet on the physicochemical, functional, and antioxidant properties of flaxseed protein.

The aim of this study was to explore the effect of atmospheric pressure plasma jet (APPJ) on the physicochemical, functional, and antioxidant properties of flaxseed protein following APPJ treatment (0 to 240 s). The results showed that the pH value continuously dropped with the minimum value of 3.45 ± 0.15 after 240 s of APPJ treatment (-61.7%, P < 0.05). The relative protein solubility significantly declined after 15 s of APPJ treatment (-43.1%, P < 0.05), which was accompanied by the evident increase in mean particle size of flaxseed protein in aqueous solution (+157%, P < 0.05). Moreover, the surface hydrophobicity and contents of disulfide bonds gradually raised when the APPJ exposure time extended from 30 to 240 s. Notably, the foaming, emulsifying, and in vitro antioxidant properties of flaxseed protein were significantly improved following short time of APPJ treatment (5 to 15 s), which was paralleled with the changes of spatial conformation, mild protein oxidation, as well as the release of phenolic acids and flavonoids from naturally occurring protein-phenolic complex. Our findings elucidated that APPJ may be considered as an effective strategy to improve the functionality and antioxidant activities of flaxseed protein. PRACTICAL APPLICATION: We had evaluated the effect of APPJ treatment on the physicochemical, functional, and antioxidant properties of flaxseed protein, which was conducive to tailor flaxseed protein with the optimal techno-functionality and antioxidant activities as a potential nano-delivery vehicle.

Structural, antioxidant and adsorption properties of dietary fiber from foxtail millet (Setaria italica) bran.

BACKGROUND: Foxtail millet (Setaria italica) bran is a by-product of millet processing, rich in dietary fiber (DF) and has great application value. A comparative study was conducted to explore the differences in structural and functional properties among millet bran DF, soluble dietary fiber (SDF) and insoluble dietary fiber (IDF). RESULTS: There was a significant difference in the content of monosaccharides between SDF and IDF, in which xylose, arabinose and glucose were the main compositions. The results of scanning electron microscopy showed that DF and IDF had different forms of network structure, and SDF presented a sign of mutual adhesion. The total phenolic and flavonoid contents were 0.54 and 0.08 g kg-1 in SDF. Antioxidant activity of SDF was higher than that of IDF based on the evaluation of free radical scavenging and iron reducing capacity in vitro. Meanwhile, the glucose dialysis retardation index of IDF and SDF was 12.59% and 9.26% at 30 min, respectively. And, there was no significant difference in the adsorption capacity of glucose among different samples (P > 0.05). Furthermore, SDF had strong α-amylase inhibition (17.92% inhibition rate) and sodium cholate adsorption capacities; the adsorption amount was 16.76 g kg-1 in 2.00 g L-1 sodium cholate solution. CONCLUSION: Foxtail millet bran DF, especially SDF, has good functional properties and would be a suitable ingredient for health-beneficial food production. However, the relevant verification trials in vivo need to be carried out in the next steps. © 2019 Society of Chemical Industry.

Effects of thermal processing on the structural and functional properties of soluble dietary fiber from whole grain oats.

Normal pressure steaming, high pressure steaming, microwave, and frying are widely used to deactivate enzyme in the oats, but these thermal processing methods may affect the structural and functional properties of soluble dietary fiber, which contribute greatly to the health benefits of oat foods. The objective of this study was to evaluate the effects of four different thermal processing methods on the structural and functional properties of soluble dietary fiber from whole grain oats. The results showed that the thermal processing resulted in changes on nutritional components of whole grain oats. Especially dietary fiber components, the total dietary fiber, insoluble dietary fiber, and soluble dietary fiber content of heat-treated oats were significantly increased ( p < 0.05). Moreover, thermal processing can not only result in an increase in molecular weight and particle size, but also cause molecular aggregation and different functional properties of soluble dietary fiber. High pressure steaming-treated oat soluble dietary fiber displayed significantly higher swelling and emulsifying ( p < 0.05), but microwave-treated oat soluble dietary fiber exhibited the highest glucose, cholesterol, and sodium cholate adsorption capacities. These results might provide basic information to help to better understand the functionality of oat soluble dietary fiber and improve the process efficiency of oat foods with high nutritional qualities.

Comparative Analysis of the Antioxidant Capacities and Phenolic Compounds of Oat and Buckwheat Vinegars During Production Processes.

This study aimed to explore the dynamic changes in the antioxidant activities and phenolic acid profiles of oat and buckwheat vinegars during different production stages. The results showed that both oat and buckwheat vinegar products comparably attenuated D-galactose-induced oxidative damage in mice serum and liver, indicating no obvious dose dependence within the tested concentrations. However, oat vinegar product revealed more favorable in vitro antioxidant activities than those in buckwheat vinegar product as evaluated by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenging abilities. Moreover, the alcoholic fermentation, acetic acid fermentation and fumigating induced successive increase in DPPH radical scavenging abilities and phenolic acid contents of the fermentation substrates of oat and buckwheat vinegars. Importantly, the different fermentation processes of oat and buckwheat vinegars were accompanied by the dynamic migration and transformation of specific phenolic acids across bound, esterified and free fractions. Thus, the antioxidant activities of oat and buckwheat vinegars could be improved through targeted modulation of the generation of specific phenolic acid fractions during production processes. PRACTICAL APPLICATION: We had evaluated the in vitro and in vivo antioxidant activities and phenolic acid contents of oat and buckwheat vinegars, and further explored the dynamic changes of bound, esterified and free phenolic acid fractions during successive fermentation processes of oat and buckwheat vinegars. This study provided the theoretical guidance for obtaining minor grain vinegar with the optimal antioxidant activities through targeted modulation of fermentation processes.

Flaxseed Oil Alleviates Chronic HFD-Induced Insulin Resistance through Remodeling Lipid Homeostasis in Obese Adipose Tissue.

Emerging evidence suggests that higher circulating long-chain n-3 polyunsaturated fatty acids (n-3PUFA) levels were intimately associated with lower prevalence of obesity and insulin resistance. However, the understanding of bioactivity and potential mechanism of α-linolenic acid-rich flaxseed oil (ALA-FO) against insulin resistance was still limited. This study evaluated the effect of FO on high-fat diet (HFD)-induced insulin resistance in C57BL/6J mice focused on adipose tissue lipolysis. Mice after HFD feeding for 16 weeks (60% fat-derived calories) exhibited systemic insulin resistance, which was greatly attenuated by medium dose of FO (M-FO), paralleling with differential accumulation of ALA and its n-3 derivatives across serum lipid fractions. Moreover, M-FO was sufficient to effectively block the metabolic activation of adipose tissue macrophages (ATMs), thereby improving adipose tissue insulin signaling. Importantly, suppression of hypoxia-inducible factors HIF-1α and HIF-2α were involved in FO-mediated modulation of adipose tissue lipolysis, accompanied by specific reconstitution of n-3PUFA within adipose tissue lipid fractions.

In vitro fermentation of oat ß-glucan and hydrolysates by fecal microbiota and selected probiotic strains.

BACKGROUND: Emerging evidence suggested that the prebiotic ability of ß-glucan was intimately related to its molecular weight (Mw ). However, the effect of oat ß-glucan with differing Mw on gut homeostasis was inconsistent. Importantly, knowledge of the fermentation properties of oat ß-glucan fractions was still limited. The present study aimed to evaluate the prebiotic potential of raw and hydrolyzed oat ß-glucan during in vitro fermentation by fecal microbiota and selected probiotic strains. RESULTS: The results obtained showed that both oat ß-glucan (OG) and hydrolysates (OGH) comparably promoted the growth of fecal Lactobacillus counts (P < 0.05). Importantly, OGH revealed greater fermentability compared to OG as denoted by lower pH value and higher short-chain fatty acid concentration (P < 0.05). Moreover, OGH was found to be more favorable to provide growth substrates for Lactobacillus helveticus R389 (LR389), Lactobacillus rhamnosus GG ATCC 53103 (LGG) and Bifidobacterium longum BB536 (BB536) than OG, and was preferentially utilized by LR389, LGG and BB536 as the sole carbon source. CONCLUSION: The results of the present study indicate that oat ß-glucan hydrolysates could serve as a more promising material for developing novel symbiotic foods. © 2017 Society of Chemical Industry.

Carnosic acid induces apoptosis associated with mitochondrial dysfunction and Akt inactivation in HepG2 cells.

Carnosic acid (CA), a phenolic diterpene isolated from rosemary, shows potential benefits in health promotion and disease prevention. In the present study, the cytotoxic and apoptotic-inducing effects of CA on human hepatocellular carcinoma HepG2 cells were investigated. The MTT assay results indicated that CA decreased cell viability in HepG2 cells in a dose-dependent manner. Treatment with CA caused a rapid Caspase-3 activation and subsequently proteolytic cleavage of poly (ADP-ribose) polymerase (PARP), both of which were markers of cells undergoing apoptosis. CA also dissipated mitochondrial membrane potential and decreased the ratio of Bcl-2/Bax protein, which mediated cytosolic translocation of cytochrome c from the mitochondria. Furthermore, CA reduced the phosphorylation of Akt, which was partially inhibited by insulin, an activator of phosphatidylinositol 3-kinase (PI3K)/Akt signalling pathway. In conclusion, our data suggest that the mitochondrial dysfunction and deactivation of Akt may contribute to the apoptosis-inducing effects of CA.

Effects of oat ß-glucan and barley ß-glucan on fecal characteristics, intestinal microflora, and intestinal bacterial metabolites in rats.

The primary objective was to determine the beneficial effects of oat ß-glucan (OG) and barley ß-glucan (BG) on gut health. A total of 200 male Sprague-Dawley rats were divided into 5 groups of 40 rats each, control group (CON), low-dose OG-administered group (OGL), high-dose OG-administered group (OGH), low-dose BG-administered group (BGL), and high-dose BG-administered group (BGH). OGL and OGH were administered oat ß-glucan by intragastric gavage at a dose of 0.35 g/kg of body weight (BW) and 0.70 g/kg of BW daily for 6 weeks, and BGL and BGH were administered barley ß-glucan. The CON received normal saline. Intestinal-health-related indexes were analyzed at baseline, week 3, week 6, and week 7. Cereal ß-glucan significantly influenced the fecal water content, pH value, ammonia levels, ß-glucuronidase activity, azoreductase activity, and colonic short-chain fatty acid (SCFA) concentrations (p < 0.05). Moreover, the population of Lactobacillus and Bifidobacterium increased (p < 0.05), whereas the number of Enterobacteriaceae decreased (p < 0.05) in a dose-dependent manner during the period of cereal ß-glucan administration. These results suggested that cereal ß-glucan might exert favorable effects on improving intestinal functions and health but the gut-health-promoting effects of oat ß-glucan were better than those of barley ß-glucan.

Hypoglycemic effects and biochemical mechanisms of oat products on streptozotocin-induced diabetic mice.

Oat products are abundant in ß-glucan, which could lower the glycemic index of products or foods. A low glycemic index is beneficial in the control of postprandial glycemia. The study examined the hypoglycemic effects of oat products that had the same percentage of oat ß-glucan and were added into the diet fed to streptozotocin-induced diabetic mice for 6 weeks, and potential mechanisms are discussed here. Oat products significantly decreased fasting blood glucose and glycosylated serum protein (p < 0.05), but the hypoglycemic effect was not more than that of metformin (p > 0.05). Oat products increased glycogen, hormone, and nuclear receptor levels (p < 0.05), decreased free fatty acid content and succinate dehydrogenase activity (p < 0.05), and inhibited pancreatic apoptosis (p < 0.05). The results showed oat products had hypoglycemic effects. Hypoglycemic effects of oat products might be regulating glucose and fat metabolisms, stimulating hormone secretion, activating the nuclear receptor, and protecting organ function.

Hypoglycaemic effects and inhibitory effect on intestinal disaccharidases of oat beta-glucan in streptozotocin-induced diabetic mice.

Most physiological studies on oat beta (ß)-glucan referred to attenuation of blood glucose and insulin responses in both healthy and diabetic individuals. The main purpose of this work was to evaluate the effects of oat ß-glucan on glucose metabolism in streptozotocin-induced diabetic mice and the activities of intestinal disaccharidases in the diabetic mice and in vitro. Meanwhile, the potentially regulative mechanisms on intestinal disaccharidases were discussed. Normal and diabetic mice, treated with metformin, were used as the negative and positive controls, respectively. The results indicated that oat ß-glucan could regulate the glucose metabolism and inhibit the activities of intestinal disaccharidases in vivo and in vitro (p<0.01), especially when using a high-dose, which suggested that oat ß-glucan could effectively improve the internal environment of intestinal tract and would be a potential alpha (α)-glycosidase inhibitor.

[Determination of degree of esterification in pectic polysaccharides from Angelica sinensis (Oliv.) diels by Fourier transform infrared spectroscopy].

An infrared spectroscopy method for rapid quantitative determination of the degree of esterification (DE) of pectic polysaccharides was developed. Taking pectic polysaccharides from angelica sinensis as samples, the calibration curve was established between DE and the ratio of A1 730/(A1 730 + A1 630). The square of the linear correlation coefficient was 0.822, indicating a good linear relationship between the DE and the absorbent area at 1 730 and 1 630 cm(-1). Using this method, the DE of pectic polysaccharides from angelica sinensis was determined to be between 42.36% and 54.06% for crude and purified samples respectively. The relationship between infrared spectroscopy data and titrimetrically determined DE values was investigated, indicating an excellent reproducibility. This method is characterized by less sample, simple manipulation, higher sensibility, and speedy analysis compared to chemical method and other instrumentations. FTIR shows a good feasibility and can be a rapid, alternative method to titrimetric analysis for DE determination.