Japonica (Tainung 67 [TNu67]) and waxy (Taichung 70 [TCW70]) rice, normal and waxy corn, and cross‐linked waxy rice and corn starches were used in an investigation of the influence of the granular structure on the pasting behavior of starch, using small amplitude oscillatory rheometry. Both normal corn and normal rice (TNu67) starches had the highest storage moduli (G′), followed by their cross‐linked versions; native waxy corn and rice starches had the lowest. Native waxy starches showed paste characteristics (G′ < 500 Pa; tan δ > 0.2) at concentrations of up to 35%. However, cross‐linked waxy starches exhibited gel behavior at 10% concentration (cross‐linked TCW70) or higher (cross‐linked waxy corn starch). The degrees of swelling power were in the order: TCW70 > native waxy corn > TNu67 ≅ cross‐linked TCW70 ≅ normal corn ≅ cross‐linked waxy corn starches. Solubilities were in the order: normal corn > TNu67 > native waxy > cross‐linked waxy starches. The addition of 2% purified amylose from indica rice (Kaohsiung Sen 7) did not induce gelation of waxy corn starch. Swelling powers of normal corn, TNu67, and crosslinked waxy starches were similar, but normal corn and TNu67 had much higher G′ value. Such results implied that the formation of gel structure was governed by the rigidity of swollen granules and that the hot‐water soluble component could strengthen the elasticity of the starch gel or paste.

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Duck eggs were pickled in alkali for 20 days to prepare Pidan. The extent of the degradation of compositional amino acids, the formation of lysinoalanine (LAL) in Pidan, and the relationship between the formation of LAL and the racemization values of D-serine and D-aspartic acid in Pidan albumen during the pickling period were investigated. Results showed that the remaining percentages of Cys, Arg, Lys, Ser, and Thr in albumen were much lower than that of the corresponding amino acid in yolk. The formation of LAL in albumen in the first stage was due to the speedy increase in the pH and the abundant formation of dehydroalanine (DHA) from cysteine. However, the formation of LAL in the later pickling period was related much more to the alkali-treating time than to the pH factor. Among the amino acids, cysteine was observed to be the most sensitive to alkaline and contributed mostly to the formation of LAL throughout the pickling period.

β-Cyclodextrin (CD)-modified micellar electrokinetic chromatography (MEKC) was applied to enantiomeric separation of Dns (dansyl-derivatized)-dl-amino acids with sodium dodecyl sulfate (SDS). Increase in the pH value and SDS concentration of the background electrolyte (BGE) buffer solution was found to prolong the migration time and improve the resolution (Rs) of Dns-dl-amino acids. Rs of each dl-amino acid was <1.0 when 100 mM SDS/75 mM β-cyclodextrin/250 mM borate (pH 8.3) was utilized as BGE buffer. However, as the pH value of the BGE buffer was increased to 9.5, all dl-amino acids, except for dl-serine and dl-alanine, were completely separated into two individual peaks. The separation was further enhanced when the SDS concentration was raised to 150 and 200 mM. Dns-d-amino acids were found to be eluted initially when compared to the corresponding Dns-l-amino acids, indicating the relatively stronger interaction between Dns-d-amino acids and β-CD. Keywords: Enantiomeric separation; Dns-dl-amino acid; β-cyclodextrin; micellar electrokinetic chromatography