The aim of this study was to evaluate the sweetness characteristics of a plant-derived sweetener from Siraitia grosvenori that contains triterpene glycosides. Sweetness qualities of four triterpene glycosides were found to be superior to rebaudioside A in stevia, dipotassium glycyrrhizinate in licorice, and saccharin sodium.
Using ripe S. grosvenori fruits as starting materials, a single-step chromatographic procedure at an industrial level yielded a concentrated extract in which four triterpene glycosides accounted for 35%. The obtained extract showed excellent sweetness-quality. When the young fruits were utilized instead, the sweetness-quality of the obtained extract was inferior to the one obtained from the ripe fruits.
Mogroside V, one of the main sweetness components of S. grosvenori, was trans-glycosylated by cyclodextrin glucanotransferase, before being partially hydrolyzed by glucoamylase to produce mogroside V derivatives to which 1 to 3 glucose residues were conjugated. The sweetness intensity of the derivatives was found to decrease as the number of additional glucoses increased. The sweetness-quality, however, was improved in the tri glucose-conjugated derivative compared with mogroside V.
In conclusion, the S. grosvenori extract is a potential source of sweeteners for various foods. In addition, when approved as a food additive, mogroside V derivatives are expected to expand the market for sweeteners.

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The structure and stability of four α-amylase inhibitors (TAI, UAI, MAI-2 and SAI-2) from Toramame (Phaseolus vulgaris L.), Uzuramame (Phaseolus vulgaris L.), Murasakihanamame (Phaseolus coccineus L.) and Shirohanamame (Phaseolus coccineus L.) were examined. The amino acid sequence of SAI-2 was the same as the known sequence for MAI-2, but was slightly different from that of TAI and UAI. The sugar chain composition of SAI-2 was remarkably different from that of MAI-2. Thermal stability at pH 5.0, 70°C indicated that SAI-2 and MAI-2 have markedly similar stabilities. Likewise, TAI and UAI, which also had identical amino acid sequences, exhibited markedly similar stabilities.
However, SAI-2 and MAI-2 were more stable than TAI and UAI. These results suggest that thermal stability of α-amylase inhibitors depends on a few amino acid substitutions in their primary structures.

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Propylene glycol alginate (PGA) was incorporated into Alaska pollack-surimi films to improve their mechanical properties. The tensile strength of PGA-surimi films prepared at pH 11 was twice as high compared to surimi films prepared at pH 7. Elongation at break was not affected by the incorporation of PGA. The water vapor permeability, film and protein solubility, and protease digestibility of PGA-surimi films were not markedly influenced by pH. The film-forming mechanism of PGA-surimi films was investigated on the basis of the changes in SDS-PAGE patterns and the available lysine content. The results revealed that the formation of cross-linkages between ε-amino groups of lysine residues in surimi proteins and mannuronic acid esters of the PGA above pH 10 was responsible for the increased tensile strength of films.

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Ethanol solution, prepared using electrolyzed tap water, was used to extract components from mulberry leaves. Compared to tap water, using acidic electrolyzed water (AEW) at pH 4 resulted in a 3% increase in the amount of 1-deoxynojirimycin extracted. The AEW extracted solution was adjusted to pH 4 and pH 5 and exhibited α-glucosidase inhibition activity of approximately 10% compared to tap water. The DPPH radical in AEW and basic electrolyzed water (BEW) exhibited an increased scavenging effect compared to tap water.

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The optimal conditions for the measurement of free fat in milk powder were determined in samples and fat-free milk powder to which defined amounts of fat were added.
It was found that approximately 90% of free fat could be extracted within a short time and under moderate conditions using carbon tetrachloride as a solvent. Experimental conditions were also found to be adequate for the measurement of free fat from fat-free milk powder.
In addition, n-hexane was also found to be suitable for use as a solvent, which is preferable given that carbon tetrachloride is harmful to humans and the environment.

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