- 著者
- Shinya Yamazaki Shoji Kaneko Yuta Takahashi Yoshihiko Amano
- 出版者
- Japanese Society for Food Science and Technology
- 雑誌
- Food Science and Technology Research (ISSN:13446606)
- 巻号頁・発行日
- pp.FSTR-D-22-00132, (Released:2023-02-16)
- 被引用文献数
- 1
Combined medium-high hydrostatic pressure (MHHP) and medium-high temperature (MHT) treatment is an effective process for liquid impregnation and food pasteurization. Although several fruit processing additives are known to inhibit polyphenol oxidase (PPO), the effect of additives on PPO activity after MHHP+MHT treatment has not been studied. This study describes the effect of citric acid and calcium chloride on PPO activity after MHHP+MHT treatment. The lyophilized powder of Fuji apples was subjected to MHHP+MHT treatment in a solution containing sucrose, citric acid, and calcium chloride, and residual PPO activity was measured. Combined citric acid and calcium chloride additive use reduced PPO activity more effectively than their individual use. Using this additive combination to decrease PPO residual activity in conjunction with MHHP+MHT proved to decrease apple compote browning homogeneously, which we believe will prove a useful method in preservation processes.
- 著者
- Sangho Koh Seika Imamura Naoto Fujino Masahiro Mizuno Nobuaki Sato Satoshi Makishima Peter Biely Yoshihiko Amano
- 出版者
- The Japanese Society of Applied Glycoscience
- 雑誌
- Journal of Applied Glycoscience (ISSN:13447882)
- 巻号頁・発行日
- pp.jag.JAG-2019_0007, (Released:2019-10-24)
- 被引用文献数
- 3
The carbohydrate esterase family 1 (CE1) in CAZy contains acetylxylan esterases (AXEs) and feruloyl esterases (FAEs). Here we cloned a gene coding for an AXE belonging to CE1 from Irpex lacteus (IlAXE1). IlAXE1 was heterologously expressed in Pichia pastoris, and the recombinant enzyme was purified and characterized. IlAXE1 hydrolyzed p-nitrophenyl acetate, α-naphthyl acetate and 4-methylumbelliferyl acetate, however, it did not show any activity on ethyl ferulate and methyl p-coumarate. We also examined the activity on partially acetylated and feruloylated xylan extracted from corncob by hydrothermal reaction. Similarly, ferulic and p-coumaric acids were not liberated, and acetic acid was only detected in the reaction mixture. The results indicated that IlAXE1 is an acetylxylan esterase actually reacted to acetyl xylan. However, since IlAXE1 was unable to completely release acetic acid esterifying xylopyranosyl residues, it is assumed that acetyl groups exhibiting resistance to deacetylation by IlAXE1 are present in corn cob xylan.