Recent developments in osmotic dehydration.
Osmotic dehydration is an operation used for partial removal of water from foods such as fruits and vegetables. In this process, foods are placed in hypertonic (osmotic) solution. Three different mass transfer mechanisms occur in the osmotic dehydration; (i) water migration from food to the solution, (ii) solute migration from solution to food, and (iii) solute concerning product extracted to solution. Osmotically dehydrated fruits and vegetables are generally dried by hot air flow. In recent years, osmotic dehydration has been combined with various methods such as the high hydrostatic pressure, high electrical field pulses, gamma irradiation, ultrasound, vacuum and centrifugal force. These new combination methods increase mass transfer and drying rate and foods by increasing the cell membrane permeability. The operation time in the combined methods is shorter than that in traditional osmotic dehydration, causing further energy saving. In this study, recent advances in osmotic dehydration will be reviewed.
Developments in Osmotic Dehydration
Publisher Summary Osmotic dehydration can be considered as the most eligible energy-saving method for the partial removal of water from foods, if and even as a method of preservation in case of candy preparation. It can affect marked reduction in the moisture content of the foods before they are subjected to further processing steps such as drying, freezing, or frying. Pretreatment with osmotic solution having concentrations lower than the natural cell concentration can improve rehydration characteristics. Osmotic dehydration can also be used for the natural concentration of fruits, which helps in obtaining better characteristics of food prepared from them, such as jam. Application of various pretreatments to osmotic dehydration such as high hydrostatic pressure, high electrical field pulses, gamma irradiation, ultrasound, vacuum, and centrifugal force, can overcome the long existing issues related to the inherently slower mass transfer rates. With the advent of newer technologies involving adsorbence and membranes, the problem of handling used osmotic solution may find newer means of resolution, which will further increase the economical feasibility of this technology.
Genetics of the phenotypic evolution in sheep: a molecular look at diversity-driving genes
Background After domestication, the evolution of phenotypically-varied sheep breeds has generated rich biodiversity. This wide phenotypic variation arises as a result of hidden genomic changes that range from a single nucleotide to several thousands of nucleotides. Thus, it is of interest and significance to reveal and understand the genomic changes underlying the phenotypic variation of sheep breeds in order to drive selection towards economically important traits. Review Various traits contribute to the emergence of variation in sheep phenotypic characteristics, including coat color, horns, tail, wool, ears, udder, vertebrae, among others. The genes that determine most of these phenotypic traits have been investigated, which has generated knowledge regarding the genetic determinism of several agriculturally-relevant traits in sheep. In this review, we discuss the genomic knowledge that has emerged in the past few decades regarding the phenotypic traits in sheep, and our ultimate aim is to encourage its practical application in sheep breeding. In addition, in order to expand the current understanding of the sheep genome, we shed light on research gaps that require further investigation. Conclusions Although significant research efforts have been conducted in the past few decades, several aspects of the sheep genome remain unexplored. For the full utilization of the current knowledge of the sheep genome, a wide practical application is still required in order to boost sheep productive performance and contribute to the generation of improved sheep breeds. The accumulated knowledge on the sheep genome will help advance and strengthen sheep breeding programs to face future challenges in the sector, such as climate change, global human population growth, and the increasing demand for products of animal origin.