Jackfruit chips are very popular in South Asia; however, the quality of traditional hot air-dried jackfruit chips is not desirable due to brown color and high hardness. The effects of three drying methods, instant controlled pressure drop-assisted freeze drying (FD-DIC), instant controlled pressure drop-assisted hot air drying (AD-DIC), and freeze drying (FD), on the physicochemical characteristics, color, antioxidant activity, expansion ratio, texture, rehydration, hygroscopicity, and microstructure of jackfruit (Artocarpus heterophyllus L.) chips were investigated. The FD-DIC-dried jackfruit chips showed the highest expansion ratio (119 %), the best color (△E, 6.5) and texture (hardness 42 N, crispness 19) compared with the FD- and AD-DIC-dried samples. A substantial increase in pore size was observed in the microstructure of the FD-DIC-dried chips. Compared with AD-DIC, the FD-DIC-finished jackfruit chips exhibited stronger antioxidant capacities (DPPH· free radical scavenging activity, ferric reducing power, and ABTS·+ radical cation scavenging activity) and higher retention of phenolics (1.2 mg GAE g?1) and carotenoids (3.1 μg CE g?1). In conclusion, the jackfruit chips produced by FD-DIC obtained a superior overall quality than the AD-DIC- and FD-dried samples. Considering the relatively high production cost of FD, this novel combination (FD-DIC) could be an alternative method for obtaining high-quality fruit chips or processing valuable agro-products. 相似文献
The instant controlled pressure drop (DIC) process was used as a post-harvesting treatment, followed by hot air drying and
shade polishing. DIC treatment, which is carried out at P = 0.4–0.6 MPa, has many advantages in terms of processing time (not exceeding 30 s) and drying kinetics (about 3 h instead
of 1 day under standard 50 °C hot air flow conditions). Shade polishing gives high quality rice with a whole-grain yield of
68-70% rather than the usual 52-60%. A tasting evaluation was carried out by an international panel and the rice was found
to be perfect after a cooking time of 6 min, with an overcooked time of 18 min as against 17 min and 20 min, respectively,
for conventional products. The shaded shelf life of the final product is much longer than 18–24 months. 相似文献
Instant controlled pressure drop (DIC) as a novel drying method can significantly expand the volume of fruit and vegetable chips, resulting in a desirable texture and crispy mouthfeel. Osmotic pretreatment (OP) is an effective processing unit used before DIC to improve the overall qualities of final products. However, the effects of OP on the texture of DIC-dried fruits and vegetables are not fully understood. Thereof, the effects of osmotic treatments on the volume, texture, microstructure, color, and sensory qualities of DIC-dried carrot chips were investigated. The results confirmed that the expanded volume of the DIC-dried samples was highly dependent on solute gain (R2?=?0.9573). According to X-ray microtomographic analysis, the microstructural characteristics of the samples were substantially affected by OP conditions, and the distribution range of pore size was broadened with increasing of osmotic time, while the homogeneity of wall thickness increased with decreasing of osmotic time. Furthermore, sensory evaluation showed that the samples appropriately pretreated (e.g., 60 °Bx for 4 or 6 min) were of great overall quality, and the indicators included hardness, volume, and color, which were significantly correlated with the solute gain (p?<?0.01). Overall, the controlled osmotic processing could be used as an excellent pretreatment for modulating the volume expansion and microstructure of DIC-dried carrot chips, thus premeditating the engineering of the texture properties.
