The fluorescence fingerprint, also known as the excitation-emission matrix (EEM), is a set of fluorescence spectra acquired at consecutive excitation wavelengths to create a three-dimensional diagram. The pattern of this diagram is unique for each measured sample, and contains abundant information about the constituents making up the sample. By combining current information technologies and large amounts of data, fine distinctions are able to be made between samples that would otherwise be indistinguishable. The following applications using this technology are discussed in this paper : discrimination of the geographic origin of mangoes ; prediction of buckwheat flour ratio in commercial dried buckwheat noodles ; and detection of mycotoxins in wheat and nutmeg.

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The purpose of this study was to develop a user-friendly indicator of improper temperature fluctuations during cold food storage. A mixture of Food Blue No.2 and Food Red No.106 in aqueous glycerol solution, which changes color from blue to red under temperature abuse, was used. Moreover, the addition of citric acid induced decreases in the usage of glycerin. To exploit this property, aqueous solutions were packed into transparent plastic bags and frozen until use. Using the color change from blue to red as a reference, the indicator could warn of temperature increases up to 96 hours at 4°C. Furthermore, earlier warnings were given at higher temperatures. As a result, a new type of indicator was developed using Food Blue No.2 with freezing.

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We investigated the relationship between phase separated structure and fracture properties of multicomponent gels. Specifically, we focused on the fracture properties of three types of gels with different continuous phases (egg white protein (EWP) continuous, bicontinuous and agar continuous). In this study, we revealed the effect of oil addition on EWP-agar gels with three different continuous phases. The fracture properties of mixed gels were analyzed by a large deformation test. Gel structure was also observed by confocal laser scanning microscopy and scanning electron microscopy. The EWP-continuous phase gel with oil showed a fracture point at higher stress and strain than the non-oil gel. Furthermore, the bicontinuous phase gel with oil fractured at lower stress and strain, but the agar-continuous phase gel with oil showed little change. The results from structural observation showed that the added oil present in the phase formed a continuous structure in the form of oil droplets. Moreover, it was clear that the oil droplets in the EWP-rich phase were active fillers. In contrast, the oil droplets in the agar-rich phase were inactive fillers. These results suggest that the interaction between oil and the component forming the continuous phase influences changes in fracture properties by the addition of oil.

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Soymilk contains various functional components, such as isoflavones, in addition to vegetable protein. In this study, we attempted to prepare cheese-like foods using soymilk, followed by sensory testing, antioxidant evaluation and isoflavone analyses of the products. First, soymilk was fermented using 11 strains of lactic acid bacteria. Isoflavone glucosides (daidzin and genistin) in soymilk were converted to their corresponding aglycone forms (daidzein and genistein) by Lactobacillus plantarum and Lactobacillus casei fermentation. Lactic acid-fermented soymilk using Lactobacillus casei MAFF 401404, which scored highly in sensory evaluation, was used for the preparation of curd. The curd was individually fermented with two kinds of cheese mold (Penicillium camemberti NBRC 32215 and Penicillium roqueforti NBRC 4622). During the 14-day fermentation/ripening period, a 10- and 11-fold increase of N-formylamino acids was observed in the cheese-like foods. Specifically, glutamic acid (umami taste) was increased and became a major component of these foods. The antioxidant potential of these foods was significantly enhanced (p<0.01) during fermentation/ripening, and exhibited 2- and 3-fold higher activities compared to unfermented curd. Malonylglucoside isoflavones, which were not hydrolyzed by lactic acid bacteria and remained in the curd, were converted by these cheese molds to their aglycone forms, which can be efficiently absorbed into the human body. These results suggest that cheese-like foods produced using soymilk have the potential to be new, acceptable, high value-added foods in the future.

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A commercially available portable near-infrared spectrophotometer that works in the short near-infrared wavelength region ([SWR], -1100nm) was employed to nondestructively measure the lipid content, a property closely related to taste, of marine fish. The objective of this study was to evaluate the capacity of two SWR spectrophotometers and a long near-infrared wavelength region ([LWR], 1600-2400nm) photometer to determine the lipid content of both the dorsal muscle of silver seabream (Pagrus major) and the liver of black scraper (Thamnaconus modestus). Spectra that was taken from intact silver seabream using all three instruments was able to be used for lipid screening. Also, good calibration equations for black scraper liver lipids were developed from the spectra of the liver ; these were obtained by dissection using all instruments. The liver of black scraper is typically found on the left side of the body. Although the spectra from the left side of the intact black scraper bodies showed absorption characteristic of liver lipids, the lipid determinations were not as accurate as those obtaining using the spectra of dissected livers. Our results suggest that LWR portable near-infrared spectrophotometers are capable of performing as well as SWR photometers for determining the lipid content of cultured marine fish. Further study to evaluate liver lipids in intact fish is required.

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A large amount of by-product is generated from Satsuma-mandarin (Citrus unshiu Marc.) juice processing, and Satsuma mandarin is a notable source of β-cryptoxanthin. Therefore, pulp produced during sieving and centrifugation processes contains large quantities of β-cryptoxanthin. We developed a process to refine β-cryptoxanthin from raw pulp materials. First, the pulp was subjected to enzymatic degradation, and the resultant precipitate was recovered by centrifugation. The water contained in the precipitate was then replaced with acetone, and the acetone-substituted pulp was directly extracted with hexane. After removal of the hexane, the extract was sequentially separated to soluble and insoluble fractions with hexane, acetone, ethanol, and a hexane/ethanol (4 : 6 or 3 : 7) mixture at -30°C. β-Cryptoxanthin was concentrated in the hexane soluble, acetone soluble, ethanol insoluble, and hexane/ethanol-insoluble fractions. Using alkaline hydrolysis, the hexane/ethanol-insoluble fraction produced non-esterified β-cryptoxanthin crystals. In the case of the isolation of β-cryptoxanthin from Satsuma-mandarin peel, after removal of essential oils in the hexane extract of dried peel under reduced pressure steam distillation, the ethanol-insoluble fraction during the sequential separation was hydrolyzed and subjected to a silica gel flash column chromatography to afford β-cryptoxanthin. The above procedure was also successfully applied to carotenoid-containing materials, and Persimmon peel produced a carotenoid mixture in high yield.

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We investigated the effects of different isoflavone aglycone ratios in lactic acid-fermented soymilk on hepatic lipid metabolism in rats fed a high fat and high cholesterol diet. Male Sprague-Dawley rats (7 weeks old) were fed a control diet (AIN-93G), high fat and high cholesterol diet, or high fat and high cholesterol diet containing fermented soymilk with a low isoflavone aglycone ratio or fermented soymilk with a high isoflavone aglycone ratio for 5 weeks. Both lactic acid-fermented soymilks exhibited lipid metabolism-modulating function, and the function was stronger in fermented soymilk with a high isoflavone aglycone ratio than in that with a low isoflavone aglycone ratio. It was proposed that isoflavone aglycones stimulated the lipid metabolism-modulation effects in liver.

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Major polyphenols in two cultivars of Japanese pear harvested during from June to September were determined and quantified, and the relationship between radical scavenging activity and polyphenol contents was assessed. Arbutin and chlorogenic acid were identified as the major polyphenols in the fruits of cultivars Kosui and Hosui. High levels of polyphenols accumulated during fructification and decreased with maturity ; however, the absolute amounts per fruit increased with time. Arbutin and chlorogenic acid were found primarily in the skin, followed by the core, of the mature fruits. It was deduced that polyphenol accumulation occurred in areas important for protecting both the fruit body from UV radiation and the seeds from oxidative stress.

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Furan is classified by the International Agency for Research on Cancer as a Group 2B carcinogen : “possibly carcinogenic to humans". It is present in many processed and cooked foods at low levels, and is determined by the balance of vaporization and generation of furan during heating processes. It is essential to know the range of furan concentrations during the cooking process to accurately estimate furan intake from cooked foods. We examined furan levels in miso soup during the cooking process, which consisted of three steps : heating, maintenance at room temperature or warm in an insulated jar, and reheating. In a common pan with a lid, furan levels in miso soup did not change during the cooking process, but increased in a linear manner in heat-maintaining cookware.

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Soyasaponins : Soyasaponins are triterpene glycosides that possess an oleanane-type aglycone with 1 or 2 polysaccharide chains. Due to differences in the aglycone compounds, soyasaponins are mainly classified as group A or B soyasaponins. Soyasaponins, especially group B soyasaponins, have been reported to have several physiological functions such as antioxidative, cholesterol-lowering, antiviral, anti-inflammatory, renin-inhibiting, hepatoprotective, and antitumor effects. We found that group B soyasaponins are more readily absorbed than group A soyasaponins, which may explain why group B soyasaponins exhibit more potent effects.
Vitamin K₂ : Vitamin K is a cofactor required for post-translational gamma-carboxylation of vitamin K-dependent proteins, including coagulation factors, anti-coagulation factors, osteocalcin (OC) in bone, and matrix Gla proteins (MGP) in arteries. Among major vitamin K homologues in foods, only vitamin K₂ as menaquinone-7 (MK-7) can activate osteocalcin, which modulates bone structure at nutritional doses. Vitamin K₂ also induces collagen accumulation in bone, contributing to bone quality and strength. In addition, MK-7 activates MGP, an artery calcification inhibitor, and is reported to be associated with the prevention of cardiovascular diseases. The higher efficacy of MK-7 compared to other vitamin K homologues is due to the better absorption and longer half-life of MK-7.

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In soybean, a number of biologically active, and thus beneficial, substances have been identified ; including isoflavone, lecithin, and saponin. Some of these are currently being marketed because their health promoting functions have been publicly approved. Moreover, recent evidence has accumulated suggesting that soybeans could contain other unused compounds with valuable functions as food additives. In this review, we focus on black soybean seed coat polyphenols (BSCP) and pinitol (PI). BSCP mainly consists of procyanidin, cyanidin 3-glucoside, and epicatechin, which are all well known for their antioxidant properties. Procyanidin represents a group of oligomeric compounds formed from catechin and epicatechin molecules. BSCP is characterized by its specific composition of procyanidin, and is particularly rich in smaller oligomer forms. It is thought that procyanidin oligomer size is inversely correlated to bioavailability. PI (3-O-methyl-D-chiro-inositol) is an inositol derivative that chiefly exists in legumes and pines, and is characterized by its extremely high water-solubility. PI content in soybean seed was reported to be around 0.2% dry weight, while in soybean plant, it is one of the major low-molecular weight carbohydrates ; moreover, it is very rich in soybean leaves (up to 2% of dry weight). Intriguingly, both BSCP and PI exert anti-diabetic and anti-obesity effects. However, they have been under-utilized mainly due to a lack of efficient methods for stable and effective handling. Here we discuss both plausible mechanisms that could enable the exertion of beneficial functions and recent developments in their preparation from raw materials.

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