内容: Most high-protein nutrition bars (HPNBs) would harden during storage, seriously affecting the acceptability of consumers. In this work, soy protein isolate (SPI), extruded at 50, 75, 100, 125, and 150 ℃, was formulated for HPNBs to investigate whether extrusion protein could relieve hardening and improve quality characteristics of HPNBs during 45 days of storage at 37 ℃. HPNBs prepared with extruded SPI were notably softer. And they had higher sensory scores than HPNBs produced with unextruded SPI during storage (P < 0.05). But there were no significant differences in hardness and total color change with the increase of extrusion temperature after 45 days of storage (P > 0.05). According to the correlation analysis, HPNBs prepared by SPI extruded at 50 ℃ had the best physicochemical properties. This study provides an effective way to relieve the hardening of HPNBs during shelf life or even longer.

内容: The influence of different wood species (in the form of wood chips) on the formation of heterocyclic aromatic amines (HAAs) in smoked Harbin red sausages was investigated. Four common species of wood (pear, oak, apple, beech) were used for smoking. The smoking process significantly affected the moisture content, water activity, pH, lipid oxidation (thiobarbituric acid-reactive substances), protein oxidation (carbonyl content) and HAA content. It was found that the wood species significantly influenced the contents of HAAs in the smoked samples. Total HAA contents were highest in samples smoked using wood chips produced from pear, followed by oak, beech and apple. The contents of Norharman and Harman were much higher than those of the other HAAs. Lipid oxidation and protein oxidation were significantly associated with the formation of total HAAs in samples. It is shown that the type of wood chips used for smoking is one of the critical parameters affecting the contamination of HAAs in smoked meat products.