Four kinds of amylopectins were isolated from tropical starches, i, e. edible canna, arrowroot, cassava and sago. Potato and corn amylopectins isolated from starches were used as controls. A 20% solution of each amylopectin was retrograded by cooling at 5°C. The retrograded amylopectin solution was studied using differential scanning calorimetry (DSC). Some differences were observed among six kinds of amylopectins in the following points : the time required for the endothermic peak to appear, enthalpy (ΔH) and re-gelatinization temperature of 20% ofamylopectin solutions stored at 5°C. Potato and edible canna amylopectins, which had a longer average chain length, had tendency to retrograde easier. Endothermic peak of cassava amylopectin appeared after about a month in storage at 5°C. Cassava amylopectin showed very different retrogradation behavior from others .

View full abstract

An agar was isolated from Gracilaria blodgettii HARVEY and its gelling properties were investigated. The total carbohydrates, uronic acid, nitrogen, ash, and moisture of the agar was estimated to be 88. 4, 1. 2, 0. 5, 3. 6, and 6.1%, respectively. The sulfuric acid was also estimated to be 1.4%. The D-galactose and 3, 6-anhydro-L-galactose residues were identified by paper and liquid chromatography from the acid hydrolysate of the agar. The optical rotation of the agar showed a value of -0.019° at a temperature of 60°C, then it decreased a little withdecreasing temperature. The infrared spectrum of the agar was in agreement with that of agarose in a wide range of wave numbers. Gelation occurred at a concentration of 0.2% at room temperature. The dynamic modulus increased with increasing concentration and showed very large value at a concentration of 0.15%. The dynamic modulus of the agar solution was stable as the temperature increased to 50°C. The agar extracted from Gracilaria blodgettiiHARVEY was estimated to have high quality in chemical components and in gelling properties.

View full abstract

The chemical composition of cell wall material obtained from sweet potatoes differing in stages of development, tissue zone and variety was determined. Only minor changes in the composition of the cell wall polysaccharides were recognized with developmental age. On the other hand, the cell wall from the peel was higher in arabinose content and lower in galactose content compared with the cambium and inner-tissue . The neutral sugar compositions of cell walls from 26 varieties of sweet potato were 1.6-2.9% for rhamnose, 3.2-6.0% for xylose, 7.1-11.2% for arabinose, 17.3-30.9% for galactose and 53.4-67.8% for glucose. The galactose to arabinose ratio ranged from 1.83 : 1 to 4.21 : 1 within these varieties.

View full abstract

The industrial production of β-glucooligosaccharide-containing syrup was developed by using the transglucosylation and condensation reactions of fungal β-glucosidase. The optimum pH (pH 4.0-4.5) and temperature (65°C) for the production of β-glucooligosaccharide were fairly close to the optimum conditions of hydrolysis reaction of cellobiose by β-glucosidase. The enzyme (1.5 units/g-glucose) was incubated with 100 kg of highly concentrated glucose solution (65%, w/w) at pH 4.0 and 65°C for 72 hr, and 88 kg of β-glucooligosaccharide syrup (Gentose® #80) containing about 45% (w/w) of oligosaccharide was produced by the reaction of the enzyme. Furthermore, 9.5 kg of β-glucooligosaccharide syrup (Gentose® #80) containing more than 90% (w/w) of oligosaccharide was fractionated by cation exchange resin column chromatography using Gentose® #45 as the raw material. These syrups tasted bitter due to the gentiooligosaccharide, especially Gentose® #45 had both a bitter taste and the sweet taste of glucose. Gentose® #45 showed similar viscosity to that of sucrose, but that of Gentose® #80 was a little higher than sucrose. The oligosaccharides of these syrups were stable under the condition of treatment for 10 min at pH 3-4 and 120t or at pH 1-2 and 100°C, and only about 10% (w/w solid) of oligosaccharides was hydrolyzed at pH 1-2 and 120°C. These syrups showed high hygroscopicity and high moisture-retaining activity. Also, these syrups reduced the freezing point of water more than sucrose, and other properties of β-glucooligosaccharide-containing syrups such as osmotic pressure and water activity were almost the same as that of sucrose. Moreover, β-glucooligosaccharide-containing syrups were not digested by pancreas origin a-amylase, and the maximum no-effect level of both syrups were estimated to be more than 0.3 g/kg. From these results, it was presumed that β-glucooligosaccharide-containing syrups might be widely used for food processing and other additives.

View full abstract

Rats fed diets containing various levels of pectin (5, 10, 15, 20%) showed morphological changes of the surface structure of small intestinal mocosa, which were observed by scanning electron microscopy. The results showed that the ileal mucosa were markedly influenced by the high pectin diet. After 2 weeks feeding with pectin diets, scanning electron micrographs revealed abnormality at the top of the villi. The longer the feeding period of the pectin diet was, the more morphological changes were observed on the surface of the villi. To confirm the effect of the pectin diet, other experiments were done. After 4 weeks of pectin (5, 10%) diet feeding, the rats were given 5% cellulose diet for 4 weeks. The ileal mucosa with abnormal morphological structure, observed with the high pectin diet, recovered to the normal state. We concluded that the effects of high pectin diet on the morphological structure of ileal mucosa were restricted to the period of pectin feeding.

View full abstract

The effects of daily administration the galactooligosaccharides (GOS ; 1 or 3g) for three weeks on fecal microflora, pH, moisture, enzyme activity, putrefactive substances and volatile fatty acids (VFA) were studied during the test period in eight healthy adult men (ages 26-57 years). The number of fecal Bifdobacterium significantly increased (p<0.01) by the 1g-GOS intake. Fecal ?A-glucuronidase and ?A-glucosidase activities significantly decreased (p<0.05) by the 1g-GOS intake. The concentration of fecal ammonia (p<0.01), phenol (p<0.05), p-cresol (p<0.01), indole (p<0.05), isobutyric acid (p<0.01) and isovaleric acid (p<0.05) significantly decreased by the 3g-GOS intake.

View full abstract

The effects of the cyclodextrins (CDs) and CD derivatives on deodorizing various odors were investigated. These exerted a deodorizing effect on n-butyric acid and trimethylamine in the gas-phase condition. Furthermore, they deodorized n-butyric acid, n-valeric acid, iso valeric acid, trimethylamine, and methylmercaptan in the liquid phase condition .

View full abstract

In recent years, more than 110 million tons of commercial sugar products (Satoh) are produced annually in the world, of which cane sugar accounted for 62 .5% and beet sugar 37.5%. Total sugar production in 1990 in Japan is approximately 2.7 million tons, of which beet sugar manufactured in Hokkaido accounted for about 650 thousand tons . The major commercial sugar produced in Japan is refined sugar and beet white sugar . The refined sugar is manufactured from cane raw sugar, although partly from beet raw sugar . Various types of sugar are produced, having different grades, qualities and appearance of products . Sugar products are divided into two classes by manufacturing process, bunmitsu-toh (centrifugal sugar) and ganmitsu-toh (noncentrifugal sugar). The refined sugar, beet sugar and raw sugar come in the former, whereas koku -toh (brown sugar lump) in the latter . The refined sugar products are also classified into two groups, soft sugar and hard sugar. While joh-haku-toh (soft white superior) and san-on-toh (soft yellow) belong to soft sugar, granyu-toh (granulated), joh-zara-toh or shiro-zara-toh(coarse crystal superior) and chu-zara-toh (coarse crystal medium) come in hard sugar . This paper describes the profile of sugar referring to historical topics, manufacturing and characteristics of commercial sugars as well as their production and consumption .

View full abstract

A lot of oligosaccharides such as maltooligosylsucrose, palatinose, fructooligosaccharides, lactosucrose and galactooligosaccharides which are produced by the transglycosylation activity of cyclodextrin glycosyltransferase, α-glucosyltransferase, β-fructofuranosidase and β-galactosidase, respectively, have been utilized as a "functional oligosaccharides ." In this paper, I will describe the synthesis of the functional oligosaccharides by transglycosylation of various microbial enzymes using sucrose as a raw material and their functions.

View full abstract