Functions of food polysaccharides to control the gelatinization and retrogradation behaviors of starch were reviewed, with a brief introduction to the physicochemical properties of starch. The conclusions of some reports cannot be easily compared to understand the molecular mechanisms for the functions of polysaccharides, partially due to insufficient purification or characterization of the polysaccharide samples. In this sense, a series of studies has recently used well-characterized samples to clarify the effects of molecular weight and other macromolecular characteristics of polysaccharides on starch behavior. Based on these recent reports, schematic figures were drawn to explain their results on a molecular level, allowing for determination of a structure-function correlation of polysaccharides. The understanding of the molecular mechanisms is necessary for the progress of the food industry from both a fundamental and an application point of view.

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6-O-Decanoyl l-ascorbate, which was synthesized by the immobilized lipase-catalyzed condensation of decanoic and l-ascorbic acids in acetone, was used for the microencapsulation of fish oil with maltodextrin (MD), gum arabic (GA), or soluble soybean polysaccharide (SSPS). The oxidation processes at 65°C and 12% relative humidity of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in the encapsulated fish oil were measured, and kinetically evaluated using the Weibull model. The oxidative stabilities of EPA and DHA in the microencapsulated fish oil were high, in the order of SSPS > GA > MD. Decanoyl ascorbate suppressed the oxidation of EPA and DHA in each system. It was indicated that the contribution of high concentrations of decanoyl ascorbate to the oxidative stability of the encapsulated fish oil is attributable to its antioxidative ability, which was due to the ascorbyl moiety in the decanoyl ascorbate molecule, but not to its emulsifying ability. In addition, it was found that the antioxidative effect of decanoyl ascorbate on the acids in the system sensitive to oxidation, such as in bulk and microencapsulated with MD, was high. Therefore, when using wall materials with a low suppressive ability for oxidation of the encapsulated oil, the application of decanoyl ascorbate would be effective.

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Response surface methodology was used to determine the optimum processing conditions that yield maximum water loss and weight reduction and minimum solid gain during osmotic dehydration of radish in sugar solution. The experiments were conducted according to Central Composite Design (CCD). The independent process variables for osmotic dehydration process were temperature (25 - 45°C), processing time (30 -150 minutes), sugar concentration (20 -60% w/w) and solution to sample to ratio (5:1 -25:1 w/w). The osmotic dehydration process was optimized for water loss, solute gain, and weight reduction. The optimum conditions were found to be: temperature - 38°C, immersion time - 100 min, sugar concentration -48% and solution to sample ratio 16:1. At this optimum point, water loss, solid gain and weight reduction were found to be 69.98 (g/100 g initial sample), 3.36 (g/100 g initial sample) and 66.61(g/100 g initial sample) respectively.

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Knowledge of the microbial population, particularly that of acetic acid bacteria (AAB), present during the fermentation process is required to produce good quality traditional rice vinegar (Kurozu). We focused on the internal transcribed spacer (ITS) region between the 16S and 23S rRNA genes of AAB for easy and rapid detection of AAB from Kurozu. Five PCR primer sets were designed to amplify the five specific DNA fragments within the ITS region of AAB. PCR amplification with these primer sets resulted in the detection of specific fragments from AAB chromosomal DNA, but not from other bacteria or yeast. Use of a DNA sample directly isolated from Kurozu mash as a template gave the same distinct PCR fragment pattern with these primer sets. This one-step PCR analysis is an easy tool for rapid detection of AAB during the long process of Kurozu fermentation and maturation.

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Fish oils extracted from 6 species of marine fin fish caught from Pulau Tuba area, near Langkawi Island, a famous tourism destination in Malaysia, were evaluated for their oxidative stability during storage at both -27 and 4°C. The five fish species were “kerisi” (threadfin breams,sScomberomorus commersoni), “kerapu” (groupers, Cynoglossus lingua), “kembong” (Indian mackerel, Psettodes crumei), “gelama kling” (drum-croaker-jewfish, Pristipomodes typus), and “tinggiri batang” (Spanish mackerels, Scolidon sorrakowah). Results showed that stability of oils stored at -27°C was better than that of oils stored at 4°C. Iodine value (IV) of oils decreased during storage, while other parameters, namely peroxide value (PV), anisidine value (AnV), acid value (AV) and thiobarbituric acid (TBA) value increased. However, the rate of quality deterioration of oil samples was relatively low, as shown by very little changes in fatty acid profiles of the oil, meaning that both storage temperatures might be used for storage purposes of fish oil.

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Effects of dietary supplementation with Fermented barley extract (FBE) on lipid metabolism and antioxidant status in mice were studied. In experiment 1, male 5-month-old mice were fed either a control diet or an experimental diet containing 10% barley, fermented barley fiber (striated part of barley grain) or FBE for 3 months. In experiment 2, male 5-month-old mice were fed either a control diet or an experimental diet containing FBE or FBEP (adsorbed fraction of FBE on the hydrophobic resin) for 3 months. The thiobarbituric acid-reactive substances (TBARS) concentrations in both plasma and liver were significantly lower in the FBE and FBEP groups than the control group. Erythrocyte glutathione peroxidase activity was significantly higher in the FBEP group than in the other groups. Liver glutathione content was significantly higher in the FBEP group than in the control group. These results suggest that FBEP, prepared from the water-soluble fraction of barley-shochu distillery by-products, significantly reduces oxidative stress in the body.

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Chemical and microbiological attributes of prebiotic kurut were investigated. Prebiotic kurut was obtained by adding inulin and fructooligosaccharide into strained yoghurt. Chemical attributes and microbiological analysis like total mesophylic aerobic bacteria, yeast and mold, lactic acid bacteria and total coliform bacteria counts were determined. Textural analyses of kuruts were also performed by texture analyzer. It was determined that using different amounts and types of polysaccharides in formulation did not affect the pH and a_w values, salt, ash, protein, water, fat and cholesterol contents and acidity values of the samples (p > 0.05). Also, firmness values, total mesophylic aerobic bacteria, lactic acid bacteria and coliform counts of kurut samples were not affected by using added polysaccharides in formulation (p > 0.05), whereas total yeast and mould counts of kuruts were affected by the formulation (p < 0.05).

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Two kinds of polyclonal antibodies against beef myoglobin were produced by immunizing rabbits with denatured myoglobin or with a peptide having the amino acid sequence unique to beef myoglobin. The latter peptide antibody reacted specifically with beef myoglobin without cross-reacting with other food proteins or with pork and chicken myoglobin. A sandwich ELISA, in which this peptide antibody was used as a capture antibody and the anti-denatured myoglobin antibody as an enzyme-labeled antibody, was also specific against beef myoglobin. When the beef content was determined in pork-or chicken-based model foods by this sandwich ELISA, the recoveries of beef protein agreed well with the actual mixing ratio of beef. Moreover, it could be confirmed by this method that the labeling of beef usage in several commercially processed foods was reasonable. Thus, a sandwich ELISA suitable for the evaluation of beef content in various foods was established.

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The spin trapping ability against alkyl-oxy and superoxide radicals was examined using a new reagent 5-(2,2-dimethy-1,3-propoxycyclophosphoryl)-5-methyl-1-pyrroline N-oxide (CYPMPO), a colorless crystalline that is very soluble in aqueous solution. For careful detection of spin adducts, we used borosilicate ESR flat cells. We examined plant specimens from teas, vegetables and fruits. CYPMPO successfully trapped alkyl-oxy and superoxide radicals in the plant extracts. We generated very pure alkyl-oxy radicals by illuminating phosphate buffer solution containing 2,2'-azobis(2-amidinopropane) dihydrochloride (AAPH) and CYPMPO with Hg-Xe arc lamp. Superoxide radicals were similarly generated using hypoxanthine (HPX), diethylene-triamine-pentaacetic acid (DTPA), CYPMPO and xanthenes oxidase (XOD). The spin adducts by CYPMPO were sensitive and very stable. The trapping activity for the alkyl-oxy and superoxide radicals was measured by the 2-amino-5-{[2-[(carboxymethyl)amino]-1-(mercaptomethyl)-2-oxoethyl]amino} 5-oxopentanoic acid (GSH) and superoxide dismutase (SOD) equivalents, respectively. Thus, CYPMPO is useful for its high capability of radical trapping.

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We examined the effects of pre-germinated brown rice on hypertension and biochemical analysis of blood in spontaneously hypertensive rats (SHRs) fed a diet including 40% pre-germinated brown rice. A significant antihypertensive effect (p <0.01) was found from day 10 of food intake, compared to controls. At completion of the test period (8 weeks), SBP in the control and test groups were 207.4 ± 5.3 and 151.6 ± 4.5 mmHg, respectively, showing a significant (p <0.001) and strong antihypertensive effect of pre-germinated brown rice. The cholesterol levels in the control and test groups were 45.3 ± 5.4 and 37.5 ± 3.9 mg/dL, respectively, which also showed a significant difference (p < 0.01). Taken together, pre-germinated brown rice has an antihypertensive effect and decreases serum cholesterol in SHRs. These effects may be due to complex actions of various components abundantly found in the rice, including γ-aminobutyric acid, dietary fiber, phytic acid and ferulic acid.

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To investigate the effects of production-related heat treatments on physicochemical properties of skim milk powder, four kinds of skim milk powder were prepared under different heating conditions. The degree of heating was expressed as the integrated caloric content added to the powders. The four skim milk powders were dispersed in water, and the physicochemical properties of them were compared. Solution turbidity increased with an increase in integrated caloric content, but the protein content in the supernatant decreased; the latter characteristic indicated that severe heating conditions resulted in aggregate formation of denatured whey protein molecules. The content of sulfhydryl groups and surface hydrophobicity of skim milk solutions were closely related to the heating conditions in the production process. SDS-PAGE analysis revealed that β-lactoglobulin and α-lactalbumin were main proteins involved in aggregate formation. The powder that had been treated with the most severe heating condition was found to be the most suitable for making bread.

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Wheat gliadin and glutenin epitopes for atopic dermatitis were degraded by crude proteases from germinated wheat seeds (PGW). PGW contained cysteine and serine protease activities and hydrolyzed gliadin epitope peptide, PQQPF, at both pH 4.5 and 7.5. The other gliadin epitope peptide, QQPFP, and the overlapped peptide of the two epitopes, PQQPFP, were fully hydrolyzed by PGW at pH 7.5, but were weakly hydrolyzed at pH 4.5. PGW also hydrolyzed the glutenin epitope peptide, QQQPP, at pH 7.5 but only partially at pH 4.5. A 16-mer peptide, CSQQQQPPFSQQQPPF (Glu-16), which incorporated this glutenin epitope twice, was also hydrolyzed by PGW at pH 4.5. Glu-16 was degraded by PGW into QQPP, QQQPP, QQPPF and QQQPPF, as confirmed by mass spectrometry.

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The essential oil from the aerial parts of hyssop (Hyssopus officinalis L.) from Iran was extracted using both hydrodistillation (HD) and supercritical fluid extraction (SFE) methods. SFE was performed at various pressures, temperatures, extraction (dynamic and static) times and modifier (methanol) concentrations using an orthogonal array design with an OA₂₅(5⁵) matrix conditions. Using GC-MS, 22 components were characterized in the oil extracted by HD. The data obtained from this study suggest that hyssop collected from Iran could be a special chemotype with a high sabinene concentration (11.04%). Major compounds identified when using SFE were sabinene, pinocamphene and iso-pinocamphene, which were extracted at different levels when applying different operational conditions. The highest selectivity of sabinene was obtained at 100 atm, 55°C, with 1.5 µL (0.05%, w/w) methanol, dynamic extraction time of 30 min and static extraction time of 35 min. Also, the highest selectivity of pinocamphene and iso-pinocamphene were obtained at 100 atm, 45°C, with 4.5 µL (0.14%, w/w) methanol, dynamic extraction time of 20 min and static extraction time of 25 min.

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By-products from potato processing plants were liquefied and partially saccharified using three commercially available enzymes, followed by ethanol fermentation by yeast and then hydrolysis by glucoamylase. From 12% (w/w) of fresh potato peel, about 20 mg/mL ethanol was formed in the supernatant via amylase, pectinase, or an enzyme complex; this yield was slightly increased with combinations of these enzymes. Supplementation of substandard mash to potato peel (1:1) as a raw material enhanced the amount of ethanol formation, increasing it to approximately 50 mg/mL by the mixture of all three enzymes. After the addition of yeast and glucoamylase to the partially saccharified material, ethanol formation proceeded gradually and slowed in 12 h with the consumption of fermentable sugars. Galacturonic acid derived from pectin was not fermented and remained in the fermented broth. In the by-products, the conversion rate of sugars to ethanol was estimated to be 42.5%.

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Eleven Bacillus subtilis strains capable of producing protease were isolated from fermented foods and characterized. B. subtilis DB and SR were selected for digesting rice proteins. It was found that they could reduce rice allergenicity by hydrolyzing allergenic fragments detected by immunoblotting. Moreover, the fact that B. subtilis SR could also digest rice proteins resulted in the increase of glutamic acid, which is the important amino acid for γ-aminobutyric acid (GABA) production. Therefore, B. subtilis SR has the potential for application in the production of hypoallergenic fermented rice-noodle with high nutrient availability.

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