On account of studying the feasibility of the production instant cereal beverage powders admixed with mulberry leaves by extrusion process, a box-behnken design of the response surface methodology (RSM) was employed to investigate the interaction of operating conditions at varying screw speed (300, 350 and 400 rpm), mulberry content (5, 10 and 15%) and feed moisture (15, 17 and 19%) on the physical and antioxidant property of product. Data were modelled by multiple regression analysis and the coefficient indicating for best fit model. The results showed that the effect of mulberry content and feed moisture had significant on bulk density, color, viscosity, water absorption index, antioxidant activity and total phenolic compound. Increasing of mulberry content resulted in finished product with higher bulk density, less lightness, less viscosity, less water absorption index, higher antioxidant activity and total phenolic compounds as a result of materials in green foods. Whereas increasing of feed moisture resulted in finished product with higher bulk density, less viscosity and less water absorption index also, but tended to lower antioxidant activity and total phenolic compounds. In addition, the optimum condition should be operated at 350 rpm screw speed, 10% mulberry content and 17% feed moisture to obtain finished product of high antioxidant activity and total phenolic compounds with good characteristics of moderate color green, easy to dissolve in hot water, palatability, and acceptability.

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A soft wheat flour, Tokutakaragasa (protein 9.69 %), was dry-heated at 120°C for 10, 20, 30, 60, and 120 minutes, and baked into Kasutera cakes (Japanese sponge cakes). The volume of Kasutera cake increased with duration of dry-heating. Also, the stability of foam in Kasutera cake batter increased with the dry-heating time of wheat flour. The mixograph profile of dry-heated wheat flour also suggests the hydrophobicity of wheat flour. Thus, the results suggest that the hydrophobicity of the dry-heated wheat flour could stabilize the foam in Kasutera cake batter and contribute to increasing Kasutera cake volume.

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In this study, the basic microbiological and chemical properties of Turkish white cheese, containing 300 ppm, 500 ppm and 700 ppm sorbic acid and potassium sorbate, ripened in brine for 90-days at 4 ± 1°C were investigated. Amount of sorbic acid and potassium sorbate added to the brine and ripening time had a significant impact on dry matter, fat, salt, salt in dry matter, titratable acidity, protein, water soluble nitrogen and the concentration of preservatives in cheese (p<0.01).During ripening, preservative diffusion to cheese significantly affected total aerobic mesophilic bacteria, coliform bacteria, and yeast-mould counts of cheese (p<0.01). Results indicated that sorbic acid and potassium sorbate could successfully be used as preservative agents in production of white cheese.

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The food kansei model (Ikeda et al., 2004) has been modified to integrate differences in personal attributes between in-house expert sensory assessors and consumer panels for sensory evaluation in the food industry. Three selection tests for expert sensory assessors revealed that the percentage of questions answered correctly on the tests had not significantly changed over the last three decades. Several characteristics of the expert sensory assessors as a surrogate consumer panel have been identified through four sensory tests for comparing the assessors. Applying correspondence analysis to the results of a questionnaire survey on the level of understanding sensory descriptors was found effective to investigate the differences and similarities in personal attributes between the expert sensory assessors and consumer panel. The modified food kansei model provides a practical path diagram to further investigate the effects of cognitive factors on sensory scores using structural equation modeling.

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Glycated whey protein isolate (WPI) was prepared by incubation of WPI with the rare sugars, d-allose (All) and d-psicose (Psi) under controlled conditions. Its emulsion and foaming properties, and its antioxidant activity were determined and compared to those of the native WPI and of WPI glycated with the alimentary sugars d-glucose (Glc) and d-fructose (Fru). WPI glycated with ketohexose showed a greater ability to form emulsions than control WPI or WPI glycated with aldohexoses. The foam overrun of all glycated WPIs was almost the same as that of the WPI control. However, the foam stability of WPI glycated with ketohexose was higher than that of the WPI control and of WPI glycated with aldohexose, following whipping for 30 min. Moreover, WPI glycated with the rare sugars All and Psi had the highest antioxidant activity as determined with the ABTS^·+ radical, even at low concentration. WPI glycated with rare sugars was then applied to ice cream manufacture and the resulting ice cream properties were evaluated and compared with ice cream made from skim milk powder (SMP). The ice cream made with added glycated WPI showed ice cream overrun and hardness that was intermediate between that of SMP and native WPI ice cream. On the other hand, the modified ice creams containing WPI glycated with the rare sugars All and Psi had significantly higher antioxidant activity than the other ice cream samples as determined with the ABTS^·+ radical. Thus, glycation of WPI with Psi improves emulsion and foaming properties and, after application in ice cream manufacture maintains high antioxidant activity. Fortification of ice cream with glycated WPI can therefore produce ice cream with excellent antioxidant activity and good ice cream qualities.

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The aim of this study was to determine the effect of processing on the chemical composition of seafoods. Raw materials and processed seafoods (canned tuna, dried horse mackerel, smoked salmon, marinated anchovy, and brine-salted bonito) were obtained from different firms and analyzed. Dried and smoked seafoods contained lower amount of moisture but higher amounts of the other components than raw materials (p<0.05). Marinated anchovies and brine-salted bonitos also contained higher amounts of fat, carbohydrate and energy (p<0.05) than raw material. Except canning with water, all processing technologies decreased the moisture content but increased fat and energy values (p<0.05) of the fish. It is concluded that processed seafoods are rich in chemical components and very nutritive, but they are generally not suitable for low-calorie diets due to the high amounts of fat and energy value. Canned tuna with salted water may be advised for low-calorie diets.

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We previously reported that soybean phospholipid administration increased the oxidative stability of fish fillets. In this study, we investigated whether dietary soybean phospholipids inhibit the oxidation of n-3 PUFA-enriched pork. Pigs in the finishing period were divided into 4 groups, and fed a commercial diet, a 1.5 % flax oil-supplemented diet, a 1.5 % flax oil-and 1 % soybean phospholipid-supplemented diet, or a 1.5 % flax oil- and 1% soybean oil-supplemented diet. The n-3 PUFA content increased in the groups fed flax oil-supplemented diet. On an oxidation test of pork fat, thiobarbituric acid reactive substance (TBARS) was elevated in the group fed flax oil. In contrast, in the group fed flax oil and soybean phospholipids, TBARS elevation was inhibited to a degree similar to that in conventional pork. These results show that soybean phospholipids increased the oxidative stability of n-3 PUFA-enriched pork.

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To evaluate the duration of antihyperglycemic effects of 6-O-caffeoylsophorose (CS), a newly identified natural α-glucosidase inhibitor from fermented purple-sweet potato, a single oral administration of CS was given to maltose-loaded Sprague-Dawley rats. Administration of CS (200 mg/kg) 30 min or 60 min before maltose administration produced an elevation of blood glucose level by administration of 2 g/kg of maltose in rats that was significantly lower than for no administration (control). In contrast, simultaneous or pro-administration of CS with maltose eliminated the antihyperglycemic effect. CS significantly reduced rat intestinal α-glucosidase activity in all of the small intestinal mucosal regions with a maximal reduction ratio of ca. 40% up to 60 min after CS administration. Thereafter, the intestinal α-glucosidase activity tended to return to basal level. These findings suggest that the antihyperglycemic effect of CS is restricted to pre-administration within 60 min.

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Rolled oats, a processed oat product, contain about 4 g of (1→3),(1→4)-β-glucan (β-glucan) per 100 g. It also contains 27.0 mg of ferulic acid and 3.5 mg of p-coumaric acid. Moreover, the presence of β-glucan, ferulic acid, and p-coumaric acid was confirmed in commercial food products with rolled oats in their lists of ingredients. The radical scavenging activity of a water-soluble polysaccharide fraction (WS) extracted from rolled oats was examined and components involved in this activity were evaluated. This WS exhibited radical scavenging activity and a strong correlation (r=0.9982) was observed between this activity in terms of the ferulic acid equivalent and WS sample concentration. Concerning the neutral sugar composition of the WS, glucose accounted for about 49 mol%, followed by xylose (about 28 mol%) and arabinose (about 15 mol%). In addition, ferulic acid was contained in a macromolecular fraction collected by gel-filtration chromatography of lichenase-treated WS. Therefore, arabinoxylan containing ferulic acid may be a component leading to the radical scavenging activity of the WS.

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The total aerobic plate count (APC), total coliform counts and the population of Listeria monocytogenes in cut cabbage, washed with distilled water (DW) and sodium hypochlorite (NaClO), were determined at 25°C and 10°C. APC, total coliform counts and L. monocytogenes population was reduced significantly just after NaClO washing (P < 0.05), however, subsequent increases in these counts were observed when stored at 25°C. When the temperature shift-up to 25°C at three different time frames (4, 16, and 24h) was applied during 48 h of storage at 10°C, it was observed that the 2 h temperature shift-up at any point did not remarkably affect the increases in APC, total coliform counts and L. monocytogenes population in either DW-washed and NaClO-washed cut cabbages. Temperature shift-up to 25 °C, applied two times during storage at 10°C, did not also affect these counts.

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Twelve sesquiterpenoids, one of which was a new compound, six tirucallane-type triterpenoids, and four flavonoids were isolated from the fruits of Schinus molle L. (Anacardiaceae). Their chemical structures were determined on the basis of spectroscopic data and X-ray analysis. Among them, three flavonoids exhibited almost identical antioxidative activity as that of α-tocopherol by the ferric thiocyanate method. In addition, one flavonoid showed a stronger radical-scavenging effect on 1,1-diphenyl-2-picrylhydrazyl than that of α-tocopherol.

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1,4-dihydroxyl-2-naphtoic acid (DHNA) is a bifidogenic growth stimulator from Propionibacterium freudenreichii. According to a method described earlier, the peak area of DHNA measured by a high-performance liquid chromatography (HPLC) gradually increases with repeated analyses of the same sample. We hypothesized that the oxidizability of DHNA was the cause of poor precision. Therefore, we attempted to develop an improved method using dl-dithiothreitol (DTT) as a mobile phase additive. A DHNA standard solution (5 µg/ml) was analyzed five times in a row by either the original or the improved method. The relative standard deviation (R.S.D.) of the peak area was 37.0% and 1.6%, respectively. The linearity of the improved method was confirmed in the range of 0.25-10 µg/ml (R² = 0.9998). These data indicate that the addition of DTT to the mobile phase improves precision of the analysis of DHNA by HPLC.

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The relationship among staphylococcal enterotoxin (SE) type, coagulase type and production of β-lactamase of Staphylococcus aureus isolates was investigated. A total of 131 S. aureus strains isolated from food samples, human hands and environmental samples were used. The predominant type of SE was SEB (66.0%) and most strains producing SEB belonged to coagulase type VI (51.4%). β-Lactamase was detected in 37 (60.3%) of the 53 SE-positive isolates. Seven (88.9%) of the 8 SEA-producing isolates produced β-lactamase. One isolate from a healthy human hand was mecA-positive methicillin-resistant S. aureus, which showed coagulase type VIII and did not produce SE. Although PCR analysis was performed to determine the staphylococcal cassette chromosome mec (SCCmec) type of this strain, SCCmec type was not classified and this strain did not carry the Panton-Valentine leukocidin (PVL) gene.

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