Evaluation and optimization of air-based precooling for higher postharvest quality: literature review and interdisciplinary perspective

Precooling is of significant importance for postharvest fruits and vegetables to control the quality degradation and prolong the shelf-life.Current precooling methods include room cooling,forced-air cooling,hydrocooling,vacuum cooling,contact or package icing,and cryogenic cooling,all of which have their advantages and disadvantages.The first two methods with the cooling medium of air are extensively used because of the wide applicable range of fruits and vegetables.Numerous studies have been devoted to cope with the drawbacks of these two air-based precooling methods with various evaluation criteria and optimization methods.A systematic literature review on these studies is firstly conducted with respect to experimental and numerical investigations respectively for the two methods.The main contributions from the previous studies are also summarized respectively with the research objectives and performance metrics.The literature review indicates that the current performance evaluation is limited to apparent parameters and the optimal design is only proposed based on the performance evaluation and comparison.Furthermore,with inspiration from the research in other domains,a scheme of advanced evaluation and optimization for air-based precooling methods is proposed with thermodynamic evaluation metrics and constructal optimization methods from the interdisciplinary perspective.

Sexual spores in edible mushroom: bioactive components, discharge mechanisms and effects on fruiting bodies quality

Edible mushroom sexual spores have been gaining more interest due to their bioactive components and functions.Spore discharge(SD)is an important factor affecting the quality of edible mushrooms.In this review,the bioactive nutrients of sexual spores of edible mushrooms were summarized,the SD mechanism was described,and the relationship between postharvest SD and the quality of edible mushrooms was analyzed.Spores contain various bioactive nutrients that are benefi cial to the human body.Mature mushrooms can actively discharge spores in a process affected by light,relative humidity,and temperature.During storage,the physiological metabolism of spore-bearing gill tissue is vigorous,promoting the release of postharvest spores and changing the nutritional value of fruiting bodies.The flavor of the fruiting bodies also varied signifi cantly during SD.Edible mushroom sexual spores have the potential to become new raw materials for functional food and medical resources.Research on the effect of the mechanism of SD on the quality of edible mushrooms and the development of SD regulation technology may be a new trend in the quality control of edible mushrooms,which will promote the development of the edible mushroom industry.

The effect of dynamic loading on abrasion of mulberry fruit using digital image analysis

The quality of fruits can be reduced due to some damages and impacts which occur during harvesting.One of the most important mechanical damages that can reduce the quality of ripe fruit quality is abrasion damage.This study focused on the effect of dynamic loading based on customary harvesting method on mulberry fruit properties.To this end,different maturity stage and storage regimes were considered.Color quality parameters,firmness,total soluble solid(TSS),total anthocyanins content(TAC)and abrasion area were the measured factors.The results revealed that none of the surveyed factors were stable during the experiment.The lightness(L^*),redness(a^*),yellowness(b^*),C^* value,firmness,TSS and TAC of immature and mature mulberry decreased during storage.The value of a^*,b^* and C^* increased as dropping height increased.However,L*value,firmness,TSS and TAC of mulberry fruit decreased at both maturity stages(immature and mature mulberry).Moreover,abrasion area increased at immature and mature mulberries by increasing the dropping height and storage time.