Anthocyanins are widely known as pigments responsible for the rich reds and purples in fruits, vegetables and legume seeds. Many flower colors are also attributed to anthocyanins. The physiological functions of anthocyanins as components in food have attracted attention, and research on their bioavailability and physiological functionality has progressed over the last 20 years. This review focuses on the health benefits of anthocyanins. It first describes the chemistry, metabolism, and absorption of anthocyanins and next summarizes the trends in research on the anti-diabetic and anti-obesity effects of anthocyanins. It then describes the other health benefits of anthocyanins, namely, the prevention of cancer and improvement of visual and brain functions, and finally discusses the challenges in and prospects of anthocyanin research.
This study evaluated the effects of infusion of grape seed extracts (GSE) at two levels (1500 and 3000 ppm) or tert methyl-butylhydroquinone (TBHQ) on thiobarbituric reactive substances (TBARS), texture, and sensory properties of baladi goat meats after cooking using microwave or conventional electric oven and stored for 12 days at 5°C. During a 12-day storage, the TBARS values of the meat cooked by microwave and conventional electric oven ranged from 0.37 to 4.47 and 0.38 to 4.61 mg malonaldehyde/kg, respectively, while that for the uncooked (raw) meat was in the range of 0.22 to 1.23 mg malonaldehyde / kg meat. Meats cooked by the microwave oven had higher TBARS values and oxidized sensory descriptive flavor than those cooked by the conventional electric oven. They also had higher maximum shear force (N), working of shear (Ns), hardness (N), springiness, cohesiveness, and chewiness values than the electric oven-cooked counterparties. TBHQ was the most effective in raw and cooked meats in reducing lipid oxidation followed by GSE infusions. Subjected sensory descriptive and consumer analyses results showed that microwave cooking was more effective for texture attribute improvement compared with the conventional electric oven. GSE were effective in preventing undesirable changes in chemical and sensory properties in goat meat caused by microwave and conventional electric oven cooking.
The effect of the subcritical water treatment along with the combination of static and dynamic modes on the recovery of protein, carbohydrate and phenolic substances from defatted rice bran was investigated at various treatment temperatures of 120, 160, 200 and 250°C and the flow rates of 0.5, 2.5 and 5 mL/min. The highest amounts of protein and carbohydrate were recovered at 160°C and that of the phenolic substances was recovered at 250°C. Around half of the protein and carbohydrate contents were degraded at 200 and 250°C. The various flow rates from 0.5 to 5 mL/min did not significantly affect the contents of the protein, carbohydrate and phenolic substances recovered from the bran. The extract also had a DPPH radical scavenging activity, which depended on the treatment temperature. While the extract obtained at 120°C at the same flow rate and same amount of water fed to the bran had the lowest radical scavenging activity, the activities in the extracts at 160 − 250°C were around 3 times higher than that at 120°C and there was no significant difference among them.
Instant rice porridge produced through cooking, drying and a series of other processes possesses inferior sensory quality which is related to the gelatinization and retrogradation of rice starch. The effects of different enzyme treatments including α-amylase, β-amylase and neutral protease and different drying methods including hot air drying, freeze drying and freeze-hot air drying on gelatinization and retrogradation of instant rice porridge were investigated in this work utilizing rapid viscosity analyzer (RVA), scanning electron microscopy (SEM) and X-ray diffraction (XRD). As for enzyme treatments, rice porridge treated by α-amylase demonstrated the lowest viscosity value and the greatest porosity which suggested that α-amylase exceeded other two enzymes in maintaining gelatinization, inhibiting retrogradation and facilitating rehydration of instant rice porridge. For different drying methods, it was found that freeze drying was most advantageous to maintain gelatinization with the lowest viscosity and the greatest porosity. This study is especially helpful to gain initial insight into the development of instant rice porridge processing technology.
Tea leaves contain unsaturated fatty acids which are precursors of aroma compounds. Despite uniform plucking practices in Kenya, plain black tea quality varies with locations. Variations in tea aroma and/or precursors with production area have not been established in a single cultivar under same agronomic input at different locations. Trials were conducted in five locations using clone BBK 35, harvested at varying intervals. The fatty acids varied (P ≤ 0.05) with locations and increased (P ≤ 0.05) with long plucking intervals, demonstrating leaf of same standard plucked at varying intervals contains different levels of fatty acids even in one location. The different increase rates in various locations might be in part the reason of the differences in aroma of black tea from different locations even when agronomic inputs are similar. Results demonstrate that harvesting at shorter intervals and developing region-specific plucking policies may improve tea quality.
An electric pasteurizer utilizing Radio-Frequency Flash Heating (RF-FH) was constructed in order to pasteurize liquid egg white. This pasteurizer inactivated Lactobacillus brevis in liquid egg white using a radio-frequency electric field. RF-FH enabled inactivation of L. brevis at 60°C in 2.4 s equally well as conventional heating at 54°C for 29.5 min. The shorter heating time yielded higher quality liquid egg white. A foam made from RF-FH treated egg white maintained its strength similarly to untreated egg white, but foam made from liquid egg white conventionally heated at 54°C for 29.5 min showed reduced strength.
Thickening agents are usually added to thin liquids administered to dysphagic patients to prevent aspiration. In this study, we aimed to identify the viscosity best suited for easy swallowing in elderly people and to examine the optimal shear rate for measuring, through sensory evaluation, these thickening liquids. Ten elderly participants were selected for sensory evaluation of diluted solutions for ease of swallowing and stickiness. Diluted solutions containing > 2.0% xanthan gum-based product were judged to be significantly more difficult to swallow than solutions containing < 2.0%. Fifty-two healthy panelists were selected for sensory evaluation of oral viscosity to compare sensory evaluation with instrument-based viscosity measurement. We found that the optimal shear rate was approximately 100 s-1. These findings indicate that the thickening agent-diluted solutions that the elderly found difficult to swallow exceeded 120 mPa·s at a shear rate of 100 s-1.
The present study was performed to determine optimum manufacturing condition for maintenance of rheological properties and retrogradation retardation of Korean rice cake, Garaedduk during shelf-life. We investigated the effect of added moisture volume and physical punching process on several rheological properties of Garaedduk. Garaedduk prepared with non-waxy rice, salt, wheat starch and 24% of water (w/w of swelling rice) was stored at 20°C for 48 h. In order to determine optimum moisture content and punching time, chemorheological and the related quality property changes were analyzed. In this study, we conducted various trials to investigate optimum condition under the five different experimental conditions prepared with manufacturing process determined by our pilot experiments. At results, the key of optimum manufacturing condition for Not-Harden Garaedduk during shelf-life is not one factor but interaction among moisture content, temperature, punching time, and grain starch property. Further study on the mechanism of retrogradation- retardation of Not-Harden Garaedduk is now in progress.
The effect of shearing on the polymorphic behavior of palm oil-based fat blends with low (LT-Fat) and high (HT-Fat) trans-fatty acid contents during storage was investigated. A shear stress was applied to fat blends at 5°C or 10°C by the flat-crush method or after rapid or slow cooling by the syringe-extrusion method. The fat networks were evaluated by cryo-scanning electron microscopy (SEM), polarized light microscopy, and solid fat content measurement, and the polymorphic transition from the β′-form to the β-form under thermal thawing between 5°C and 20°C was investigated by X-ray diffraction. Transition to the β-form of LT-Fat with shearing was retarded compared with that without shear. SEM revealed that with shearing, LT-Fat built complex networks involving both fine reticulation and a tight structure, whereas without shearing, the structure was nearly uniform. These results suggest that the non-uniformly network achieved by shearing could suppress the localization of specific triacylglycerides, preventing transformation into the β-form.
We examined the effects of adlay protein concentrates (AP) on lipid metabolism and on in vivo oxidative stress in type 2 diabetic db/db mice. Mice were fed an AIN-93G diet containing either adlay grains (AG) or AP for 21 days. Plasma parameters, such as total cholesterol, arteriosclerotic index and thiobarbituric acid reactive substances (TBARS) concentration in the diabetic AP-fed group were lower than those in the diabetic control (AIN-93G) group. Concentrations of hepatic parameters, such as total cholesterol, triglyceride and TBARS levels, in the AP-fed group were lower than those in the diabetic control group. A pronounced improvement in lipid metabolism of the AP-fed group was observed when compared with the AG-fed group. It was deduced that excretion of bile acids and cholesterol in the feces of mice fed the AP diet abundant in resistant protein contributed to the suppression of plasma and hepatic cholesterol concentration in diabetic mice.
The feeding of unripe persimmon (PP) (‘Hiratanenashi’, pollination variant) and soluble tannin (PST), as its component, on blood pressure was examined in spontaneously hypertensive rats (SHR). Systolic blood pressure (SBP) was decreased by PP and PST administration for 2-3 days and increased after switching to the basal diet alone. Increases in serum nitric oxide level and liver NOS3 gene expression in SHR fed PP suggests that the induction of nitric oxide formation by PP administration might be involved in decreasing SBP. The decrease in ACE activity by PST administration suggests that, as a component of PP, PST mainly lowers SBP through its angiotensin I-converting enzyme (ACE) inhibitory effect. Scopoletin, contained as a minor component in PP and PST, decreased SBP by single oral administration, suggesting that it also might be involved in lowering SBP.
Citrus seeds represent substantial wastes of citrus-processing. Oils extracted from orange (Citrus sinensis), lemon (Citrus limon) and tangerine (Citrus reticulata) seeds were investigated. The seeds were removed from the fruits, washed, dried at room temperature, ground and the oils extracted using a Soxhlet extractor. The seed oils were analyzed in terms of the lipid content, fatty acid, tocopherol and carotenoid compositions, total phenolic content, oxidative stability and the radical-scavenging activity. The oil content of citrus seeds ranged from 34.92 to 41.66%. The oils showed high degrees of unsaturation and essential fatty acids. Oils exhibited also natural antioxidants specially tocopherols and phenolic compounds. Oxidative stability and antioxidant activity were influenced by unsaturated fatty acids and tocopherol contents in the analyzed oils.
In this study, we obtained water-soluble nucleotide-extract from six kinds of edible fungi (Agrocybe chaxingu, Lentinus edodes, Coprinus comatus gray, Agaricus bisporus, Armillariella mellea, Flammulina velutipes), and the extract from Agrocybe Chaxingu sporocarp exhibited the highest total reducing power and the most remarkable scavenging activity on 2,2′-azino-di(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), which had a good dose-response relationship with the concentration of water-soluble nucleotide. When the concentration of the nucleotide was 20 mg/mL, the ABTS scavenging rate could be 90%. The nucleotide-extract was also found to exhibit remarkable scavenging activity on hydroxyl radicals (EC50 = 18.5 mg/mL), superoxide anion radicals (EC50 = 38.4 mg/mL) and lipid peroxidation inhibition activity (EC50 = 8.1 mg/mL). Moreover, the main nucleotides in the nucleotide-extract were identified by HPLC, which were respectively AMP, CMP, GMP, UMP, ADP, GDP and GTP in a molar ratio of 1:2.17:3.49:1.7 6:0.75:4.18:1.67. These results indicated that the nucleotide would be a new antioxidant with wonderful prospects.
Mung bean sprouts turn brown during cold storage. Here we showed that heat-shock treatment inhibited this browning by repressing the induction of phenylalanine ammonia-lyase (PAL) activity and the biosynthesis of polyphenols during cold storage. Mung bean sprouts were soaked in warm water at 50°C for 60 s as heat-shock treatment and then stored at 8°C for 6 days. Heat-shocked mung bean sprout turned less brown than that of the control sprout. The PAL activity in the control significantly increased during cold storage, while that in heat-shocked mung bean sprouts did not. The polyphenol content in heat-shocked mung bean sprouts was lower than that in the control at 3 and 6 days. There was no significant difference in polyphenol oxidase activity between the control and heat-shocked mung bean sprouts during cold storage. These results show that mild heat treatment inhibited the enzymatic browning of mung bean sprouts by repressing the induction of PAL activity during cold storage and the accumulation of polyphenols.
Well-documented stability studies on iron-fortified food are limited due to the complexity of ingredients and processing methods. Here, we performed a comprehensive stability evaluation on iron-fortified milk powder with various iron contents and packaging methods. Free fatty acid increased gradually over a 9 month storage period in both iron-fortified and non iron-fortified formulas, regardless of the packaging methods. Thiobarbituric acid (TBA) value level remained stable in anaerobic packaging condition but increased in aerobic condition. Lipid oxidation was highest in Fe(III)-fortified formula. We showed significant increment of browning reactions, moisture and water activities in aerobic condition, especially in iron-fortified formulas, while no significant changes in anaerobic-packaged formulas. Scanning electron microscopy (SEM) showed highest porosity in Fe(III)-fortified formula. Our results showed Fe(III)-fortified formula has the lowest stability in aerobic condition but its stability improved significantly with vacuum/anaerobic packaging. Thus, our studies contribute to understanding and improving the processing and quality of iron-fortified food.
Three compounds of volatile thiols, 2-furanmethanethiol (2FM) with a strong roast coffee aroma, benzenemethanethiol (BM) with a strong empyreumatic aroma reminiscent of smoke and ethyl 2-mercaptopropionate (ET2MP) with a tropical fruit-like aroma, were identified for the first time in four types of heat-treated soy sauce and raw soy sauce. 2FM, BM and ET2MP were present in these soy sauce samples at considerably higher concentrations than their perception thresholds. Their concentrations also increased when the raw soy sauce was heated for pasteurization. A triangle test on the raw soy sauce and heat-treated soy sauce showed that the aroma of the raw soy sauce became similar to that of the heat-treated soy sauce after the addition of the three volatile thiols to the raw soy sauce. The volatile thiols thus contributed to the aroma of heat-treated soy sauce.
This study was investigated the survival and growth of pathogens on commercial dish sponges and cloths when contaminated with organic materials and the effects of chemical sanitizers and organic acids on inhibiting pathogens contaminating the dish sponges and cloths. When pathogens were inoculated with TSB, none of the four pathogens grew in the cellulose sponge until 12 h of storage; however levels of pathogens on the other samples were significantly increased after 24 h of storage. When chemical sanitizers and organic acids were added to the dish sponges and cloths, treatments with hydrogen peroxide-based sanitizer, lactic and propionic acids were the most effective at reducing levels of E. coli O157:H7 and S. aureus, whereas treatment with a chlorine sanitizer did not significantly reduce pathogen levels.
Common bean (CB) bulgur, is a variety of new parboiled and dried product, was produced with soaking different soaking time (2, 8 and 12h) and soaking water pH (pH 4, 6 and 8) in this study period. Experiment was conducted according to (3 × 3) × 2 factorial designe. Physical, chemical nutritional, and anti-nutritional components of raw and CB bulgur samples were determined. Total phenolic content and phytic acid reduced at a ratio 41 − 57% and 48 − 57% respectively, while trypsin inhibitor activity was completely eliminated after 12 hour soaking time. The highest in vitro protein digestability (73.4%) was measured in CB bulgur samples with soaked at pH 8 soaking water. The highest HCl-extractability of ash value (65.57%) of CB bulgur samples obtained by soaking at pH 6 soaking water. HCl-extractability of K, Ca, P, Mg, Zn and Fe increased with levels of 3 − 7%; 17 − 19%; 29 − 34%; 15 − 21%; 15 − 22%; and 28 − 52%, respectively with increasing soaking time. The optimum soaking process condition was found as 12 h soaking time and 8 pH soaking water for obtaining highest nutritional properties of CB bulgur, except an adverse effect on texture and taste score of bulgur.
We investigated lipid oxidation, instrumental color evaluation, and sensory characteristics in cooked pork sausages containing anthocyanin rich colored potato (Solanum tuberosam cv. Shadow Queen) flakes (CPF). According to the thiobarbituric acid reactive substance values, addition of 2% CPF suppressed lipid oxidation (P < 0.05) by 80% compared to the control. The antioxidant activity of 2% CPF was comparable to the synthetic antioxidant butylated hydroxytoluene (0.1%) in cooked pork sausages. The L, a* values and odor, flavor, taste, texture and overall sensory quality did not significantly differ between control and 2% CPF. Overall, cooked pork sausage with 2% CPF was as acceptable to consumers as the control. Thus, the present study indicated that the addition of 2% CPF was effective as a natural antioxidant for suppressing lipid oxidation in cooked pork sausages.
Lotus plant (Nelumbo nucifera Gaertn) is well known for its therapeutic effects despite its ability to accumulate heavy metals. This study evaluates antioxidant properties and heavy metal content of seed, stem and rhizome of lotus that grown in ex-tin mining pond. Total phenolic content, DPPH-radical scavenging activity and tyrosinase inhibition activity were determined on methanol extracts. Contents of ash, lead and chromium were determined on dried, ground samples. The highest concentration of phenolic content, ash, lead and chromium is in the seeds. Tyrosinase inhibition activity is highest in the rhizome and lowest in the stem. Correlation of DPPH-radical scavenging activity is good with tyrosinase inhibition activity (P < 0.01). The concentration of lead found exceeded the permissible limits of Codex Alimentarius. Therefore, assessment of metal contamination should be a mandatory priority to utilization of abandoned ex-tin mining area for edible plant cultivation.
The anti-allergic effects of the edible brown alga, Ecklonia stolonifera, are known to affect both degranulation in KU812 cells and anti-inflammatory properties of RAW 264.7 cells. Additional anti-allergic effects of E. stolonifera extracts were therefore investigated by examining the inhibitory effects of algal extracts on enzymes associated with eicosanoid synthesis, the inflammation reaction, and anti-degranulation activity in rat basophilic leukemia (RBL) -2H3 cells. A methanol: chloroform (1: 2, v/v) extract of the alga inhibited the enzyme activities and degranulation in stimulated RBL cells in a dose-dependent manner. When phenolic compounds were removed from the M/C extract by treatment with polyvinylpolypyrrolidone resin, the obtained residue did not exhibit the same inhibitory activities. These results imply that the active compounds present in the M/C extract may be phenolic compounds, such as phlorotannins. In addition, the novel anti-allergic effects of E. stolonifera that contributed to inhibiting the enzymatic activities were also clarified.
The purpose of the present study was to examine the antidepressant-like effects of an aqueous extract of lavender (LAE) using the forced swimming test (FST), the most widely used animal model of depression. LAE was orally administered to rats three times, i.e., 24, 5, and 1 h prior to the FST. The administration of LAE (3428 mg/kg body weight) showed a significant reduction of the immobility time in the FST, the effect of which was comparable to that of the synthetic antidepressant, imipramine (30 mg/kg). In addition, the same dose of LAE did not change the locomotor activity in the open field test. These results suggest that LAE might have antidepressant-like effects that are independent of motor stimulation. Furthermore, the active ingredients of LAE were suggested to be non-volatile constituents, because linalool, the main aroma constituent of lavender, was completely removed during the preparation of LAE. Possible contribution of rosmarinic acid and that of apigenin glycosides to the antidepressant-like effects of LAE were discussed on the basis of their content in LAE.
We found that a wheat bran arabinoxylan (WBA) activates the phagocytosis of 1,25-dihydroxyvitamin D3-differentiated HL60 cells; however, its mechanism was unknown. Hence, we investigated the molecular mechanism involved in the WBA-induced increase of immunostimulating activity using inhibitors. The results indicated that the WBA-induced increases in phagocytic activity and IL-1β production were inhibited by cathepsin B and caspase-1 inhibitor. Moreover, IL-1β production was inhibited by a phagocytosis inhibitor.
Phycobiliproteins were purified and characterized from an edible cyanobacterium, Nostochopsis sp. C-phycocyanin and allophycocyanin were simultaneously purified by about 3.9- and 4.3-fold to provide yields of 23 and 29%, respectively, from cell extracts using simple purification steps, such as ammonium sulfate fractionation and anion exchange chromatography. The purified preparation was eluted as a single peak with an apparent molecular mass of 117.0 kDa during a gel filtration. Polyacrylamide gel electrophoresis of the purified preparation yielded a single protein band in the absence of SDS, but in the presence of SDS, three protein bands with apparent molecular masses of 18.5, 16.5 and 15.5 kDa were formed. These results suggest that the purified preparation consists of C-phycocyanin and allophycocyanin, both of which were strongly associated with one another during purification. Furthermore, the purified Nostochopsis preparation (1 mg·mL-1) showed considerable antioxidant capacity (11.6 μmol·L-1 trolox equivalent), which was similar to that (10.5 μmol·L-1 trolox equivalent) of Spirulina C-phycocyanin.