Sweet potato is a nutritious, cost-effective and abundantly available food crop in Asia. In an effort to utilize sweet potato for food processing, the effects of purple sweet potato powder (PSPP)-supplementation on the quality of fresh pasta was determined. Results showed that PSPP-supplementation produced fresh pasta dark purple in color, attributable to the intrinsic anthocyanin content. Moreover, PSPP provided a higher amount of gelatinized starch, resulting in softer and more elastic raw fresh pasta; and the boiled fresh pasta showed a softer texture, as indicated by its hardness, rupture force and energy. However, PSPP-supplementation decreased the cooking weight gain of fresh pasta. Sensory evaluation rated the quality of boiled fresh pasta with 7.5% and 10% PSPP as more acceptable and equally acceptable as the control, respectively. Thus, this study suggests that PSPP-supplementation results in an acceptable noodle product, potentially increasing the utilization of purple sweet potato.
Isada krill (12.5 kg) was first treated under subcritical water conditions at 140°C or 160°C by injecting steam into a large pressure-resistant vessel, and it was then separated into liquid extract and solid residue. The solid content, salt concentration, protein content, antioxidative activity, and odor intensity of the extract, as well as the color and odor of the residue, were determined. The preference score and flavor characteristics of both the extract and the residue were assessed by sensory evaluation. The results for the extracts and residues prepared by the large-scale treatment were roughly the same as those for the extracts and residues prepared using a 117-mL small vessel operated at similar severity factors. Both the extracts and residues exhibited a pleasant shrimp-like flavor, and would be promising as seasonings.
Lactobacillus paracasei HD1.7, an isolate from Chinese fermented cabbage and producer of bacteriocin, was used as a starter culture to estimate the impact on characteristics of fermented cabbage. The results of quantitative real-time PCR showed that in Lb.paracasei HD1.7 fermented sample, the total bacteria number was significantly higher during the initial and medium stages. Lb.paracasei HD1.7 significantly increased the final concentration of lactate (7.13 g/L), mannitol (19.41 g/L) and seven amino acids while kept vitamin C more stable (43.20 mg/kg). Meanwhile, nitrite was lower than 0.16 mg/kg throughout the whole fermentation process. The fermented cabbage with Lb.paracasei HD1.7 was more favorable by consumers in terms of crisp, sourness, aroma, bitterness, stink, stale flavor and overall acceptability. Lb.paracasei HD1.7 fermented cabbage had more nutritive values and health-promoting effects. This suggested Lb.paracasei HD1.7 a practical potential in industrially production as a starter culture of fermented cabbage and other fresh vegetables.
Acid stress is an environmental condition commonly encountered by lactic acid bacteria in the gastrointestinal tract and fermented foods. In this study, adaptive evolution of Lactobacillus casei was conducted in MRS broth at 37°C for 70 days, and three acid-tolerant strains were isolated. The evolved strains exhibited more than 60% increases in biomass than the parental strain when cultured at pH 4.3 for 54 h. Then, the tolerances of the evolved strains to acid stress, bile salt, and simulated gastrointestinal juice were determined. Acid tolerance was investigated by exposing the evolved strains and the parental strain in pH 3.3 and pH 2.5 of lactic acid and HCl-adjusted MRS broth respectively. The evolved strains showed higher survival rate than the parental strain. In addition, the evolved strains exhibited higher resistance to simulated gastric juice (pH 2.5), simulated intestinal juice (pH 8.0), and bile salt (1.6%). Analysis of the intracellular pH (pHi) showed that the evolved strains exhibited higher pHi compared with that in parental strain. The enhanced tolerance of the evolved strains to various stresses observed in this study provides a possible procedure for the food industry to select environmental-resistant strains and may be important in the production of probiotics.
In order to identify objective parameters for quality evaluation, physical dimensions, pH, color parameters, proximate composition, water activity, lipid oxidation, free amino acids, mechanical properties, protein composition and differential scanning calorimetry of commercial Japanese spicy pollack roe products of differing quality were analyzed. Low-priced roe products showed significantly higher (p < 0.05) average thiobarbituric acid reactive substances content than high-priced roe products from the same company. More bitter amino acids were detected in the low-priced, compared to the high-priced roe products from the same company. Ovary membrane and eggshell proteins in low-priced roe products were comprised of a relatively greater amount of low-molecular-weight components. Compared to low-priced roe products, high-priced ones showed higher values for the mechanical properties and thermal transition enthalpy of fish egg.
Outbreaks of food-borne illness caused by Listeria monocytogenes in or on fresh produce are sometimes reported. Tomatoes have been considered as one of the most implicated vehicles for produce-associated outbreaks. In the present paper, using tomato plants and three isolates of L. monocytogenes showing different serotypes (1/2a, 1/2b, 4b), viability and injury of L. monocytogenes in soil and in or on tomato plants during cultivation was investigated. Soil was artificially contaminated with L. monocytogenes at levels of 2, 4, 6 or 8 log CFU/g, followed by cultivation of tomato plants in the contaminated soils. The population of L. monocytogenes in the soil decreased to less than the detection limit (< 2 log CFU/g) 6 – 8 weeks after the start of cultivation. L. monocytogenes was not detected in any harvested fruit after a 16-week cultivation, although it was detected qualitatively from soil samples. Artificial injury of the root did not induce contamination of tomato fruit by L. monocytogenes via vessels. Thus, the possibility of internalization or contamination of tomato fruit by L. monocytogenes from contaminated soil is considered quite low during cultivation. However, L. monocytogenes on the fruit surface survived up to 2 – 3 weeks. Regardless of contamination level, hygienically inappropriate handling by workers might lead to contamination of tomato fruit by bacteria such as L. monocytogenes and thus to food poisoning.
29 grape cultivars, of seeded and seedless raisins from black, reddish-brown and yellowish-green grape varieties were examined to determine the relationship between grape color, seeded status and raisin phenolic content. The raisins were analyzed for phenolic profile, total phenolic (TP) and flavonoid contents (TF), and antioxidant activities (DPPH, ABTS and FRAP). We found that despite the perception that dark colored raisins, contain higher levels of polyphenolic antioxidants, only seedless raisins from black grapes were higher in TP. Black raisins exhibited significant higher values of TP and FRAP activity than reddish-brown and yellowish-green raisins. The values of TP, TF, DPPH, ABTS, and FRAP capacities for seeded raisins were higher than those of seedless samples. Raisins could be classified into three groups and some raisins differing in seed-bearing status or color were grouped together, indicating the antioxidant properties of raisins were not only determined by raisin color, but also by their seed-bearing status.
Yaowang tea, the leaves and flowers of Potentilla glabra Lodd. (family Rosaceae), has been used for a long time to prevent and mitigate hyperlipidemia, hypertension, diabetes and so on. According to this research, twelve flavonoids were isolated and all the flavonoids were obtained for the first time in P. glabra. The different polar portions (petroleum ether portion, ethyl acetate portion, n-butanol portion and water portion) and six flavonoids from P. glabra were screened, and their antioxidant abilities were measured by DPPH and FRAP assays. Six tested flavonoids showed significant free radical scavenging capacity in the DPPH assay and total antioxidant activity in the FRAP assay compared with Vitamin C (Vc). This work provides an understanding for the flavonoids of P. glabra and lays the foundation for the future research.
Biological control is an alternative to synthetic fungicides to avoid postharvest diseases which limit the storage period and marketing life of fruit and vegetables. Present investigation is focused on the isolation, identification and characterization of Bacillus subtilis CF-3 from fermented bean curd through the analyses of phenotype, physiological and biochemical characterization, 16S rDNA gene sequence based on its biocontrol effect against pathogens (Monilinia fructicola, Cephalothecium, Rhizoctonia and Alternaria) causing peach decay. With treatment of CF-3, the ratio of good fruit was 65% which was higher than 30% in the control group significantly after 36d storage at 10°C and 65% compared with 50% in the control group after 7d storage at 25°C; The optimal growth temperature and pH of CF-3 were 37°C and 8; The results of antimicrobial stability indicated that CF-3's antibiotics had good UV, pH and thermal stability (except at 121°C). Findings of the present study suggested that the antifungal properties of CF-3 may have a potential to be developed as fungicide which can contribute to the postharvest preservation of peach fruit and provide a theoretical basis for the further study of biological control.
The effect of germination on the antioxidant capacity of pigmented and non-pigmented rice was investigated. The blackish purple Superjami, reddish-brown Superhongmi, and ordinary non-pigmented brown rice were germinated for 72 h. The germinated rice grains were extracted with 80% methanol and their antioxidant activities and compounds were analyzed. Germination substantially increased the free radical scavenging activity, reducing power, ferrous chelating ability, and superoxide dismutase activity in all the rice samples. The anthocyanin, tannin, phenolic, phytic acid, tocopherol, and tocotrienol contents were markedly higher in germinated rice compared to those of the non-germinated ones. The pigmented varieties exhibited greater antioxidant capacity and higher amounts of antioxidant compounds than the non-pigmented brown rice in both germinated and non-germinated forms. Superjami showed higher antioxidant activities and anthocyanin, phenolic, tocopherol, and tocotrienol contents than Superhongmi. These findings illustrate that germination could increase the antioxidant compounds and enhance the antioxidant capacity of pigmented rice which may be useful as functional foods.
Soft rush (Juncus effusus L. var decipiens), known as igusa, is locally cultivated as an edible organic crop, and the dried powder is applied to the processing of unique foods in Japan. The current study investigates the anti-inflammatory effects of edible soft rush using lipoxygenase and hyaluronidase assays, and an activated macrophage cell model in vitro. Matcha green tea powder was tested for comparison. Hot-water and ethanol extracts of soft rush as well as matcha showed comparable lipoxygenase inhibition, with IC50 values of 123 to 145 µg/mL. For the hyaluronidase assay, IC50 values of the samples were 1.16 mg/mL or more. Macrophages cultured in the presence of hot-water and ethanol extracts of soft rush showed strongly suppressed nitric oxide production (IC50 of 120 µg/mL and 35.2 µg/mL, respectively) compared to matcha in a lipopolysaccharide-activated cell model. These results support the potential usefulness of edible soft rush powder for anti-inflammatory purposes.
Cisplatin-treated rats experienced a significant elevation of serum activities of lactate dehydrogenase (LDH), aspartate transaminase (AST), alanine transaminase (ALT) and creatine kinase (CK). These effects were accompanied by significant increases in the levels of malondialdehyde (MDA) and nitric oxide (NO), and decreases in the glutathione (GSH) content, and the activities of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) in cardiac tissues. Pathological examination revealed that cisplatin caused significant cardiac damage in rats. Grape seed proanthocyanidins extract (GSPE) administration produced amelioration in biochemical indices of cardiotoxicity, lipid peroxidation, oxidative stress, as well as histological change when compared to group cisplatin alone. GSPE were shown to be potential candidates to ameliorate cisplatin-induced cardiotoxicity.