Effectiveness of additives in spray drying performance: a review

The systemic review covers the efficiency of additives on spray dried product; process parameter and its physicochemical properties. Due to the demand of diversification of food products, conventional spray drying process has gained momentum in drying process and extensively used to preserve food materials in powder form. Regarded as a complex operation, the balance between optimization of spray drying process parameters and physiochemical of its product has proven to be a challenge, especially in low product yield due to low transition temperature of feed material. This paper envelope the usage of additives as carriers in spray drying processes, and its effects on physicochemical properties such as hygroscopicity, flavour retention, and colour indexing. The literature signified the vital role of additives in enhancing the physiochemical of feed material and highlighted the effect of additives on spray drying efficiency in respect to its process parameters. Studies advances have shown that additives have improved significantly on products feed characteristic; lower moisture content, higher process yield, and powder flowability. Further research has shown a combination of additives enhances certain properties of feed material. The study signified the effect of additives as a vital role in improving the physicochemical properties of spray-dried powder. The difficulties of achieving powder specification demands can be resolved, by understanding and utilize the knowledge of additives on processing parameter of spray drying

Anoxia tolerance in tobacco roots: effect of overexpression of pyruvate decarboxylase

Plant survival during flooding relies on ethanolic fermentation for energy production. The available literature indicates that the first enzyme of the ethanolic fermentation pathway, pyruvate decarboxylase (PDC), is expressed at very low levels and is likely to be rate-limiting during oxygen deprivation. The authors expressed high levels of bacterial PDC in tobacco to study the modulation of PDC activity in vivo, and assess its impact on the physiology of ethanolic fermentation and survival under oxygen stress. In contrast to leaves, wild-type normoxic roots contained considerable PDC activity, and overexpression of the bacterial PDC caused only a moderate increase in acetaldehyde and ethanol production under anoxia compared to wild-type roots. No significant lactate production could be measured at any time, making it unlikely that lactate-induced acidification (LDH/PDC pH-stat) triggers the onset of ethanol synthesis. Instead, the authors favour a model in which the flux through the pathway is regulated by substrate availability. The increased ethanolic flux in the transgenics compared to the wild-type did not enhance anoxia tolerance. On the contrary, rapid utilisation of carbohydrate reserves enhanced premature cell death in the transgenics while replenishment of carbohydrates improved survival under anoxia