A1 Printed in the Islamic Republic of Iran

Abstract -Showing the occurrence of glass/rubber transition in bovine serum albumin (a globular protein) at low moisture levels and the occurrence of Maillard crosslinking in gelatin in previous works, the importance of the state of glass or rubber of BSA on the rate and extent of polymerisation, protein solubility, colour and SDS PAGE patterns in the presence and absence of ascorbic acid, diketogulonic acid and dehydroascorbic acid was investigated. BSA on storage with Ascorbic acid and its degradation products at low moisture contents (8.3% and 19.1%) at a relatively low temperature (40ºC) can undergo chemical changes resulting in marked increase in molecular weight, solubility decrease and formation of browning colour. The glassy state data established the occurrence of chemical changes (Maillard crosslinking and disulfide crosslinking) in the BSA system on storage below its glass transition temperature

Accelerated Ripening of Kabkab Dates Using Sodium Chloride and Acetic Acid Solutions

ABSTRACT-In this research, the accelerated ripening of the Kabkab dates from Khalal to Tamr using NaCl and acetic acid solutions was studied. Fruits at Khalal stage were harvested and washed with distilled water before being treated with ripening inducers: 1. NaCl solutions, 2. acetic acid solutions and 3. Aqueous solution of NaCl (1%) and acetic acid. moisture, pH, colour, brix and textural firmness of the samples were monitored. Results indicated that during ripening the moisture content and colour changed significantly. The major change was observed for firmness where a maximum force for puncture test varied from about 1000 to 50 g force for all samples after 72 hours of incubation at 40 °C. Harvesting at Khalal stage followed by treating the fruits with NaCl and/or acetic acid solutions and an incubation stage at 40 °C showed to be a promising method for accelerated ripening

Fructan Contents in Australian Wheat Varieties Released Over the Last 150 Years

Grain fructans play an important role in the physiology of wheat plants and also impact on the health of consumers of wheat-based products. Given the potential economic importance of fructan levels, if genetic variability could be identified for this trait, it may be a potentially useful breeding target for developing climate-resilient and nutritionally enhanced wheat varieties. The aim of the current study was to screen 78 genetically diverse Australian wheat varieties released between 1860 and 2015 to determine if historic breeding targets have resulted in changes in fructan levels and to identify potential breeding parents for the development of varieties with specific fructan levels. The impact of seasonal conditions on grain fructan levels were also investigated. Analysis of the varieties in this study indicated that historic breeding targets have not impacted on grain fructan levels. Fructan content in flours varied between 1.01 to 2.27%, showing some variation among the varieties. However, a significant variation in fructan levels was observed between different harvest years (mean values for 2015 and 2016 samples were 1.38 and 1.74%, respectively). While large variations in fructan contents of different varieties were not found, there were some varieties with consistently higher or lower fructan contents which could be used to breed varieties with specific fructan levels

An investigation on physical ageing of β-lactoglobulin and implications for its storage

Due to the importance of physical ageing in functional properties of the globular protein of β-lactoglobulin as the main protein of whey powder (the by product of cheese manufacturing industry) the possible occurrence of physical ageing in dry powder of β-lactoglobulin with moisture content of 15.9% was studied at different temperatures below and close to the glass transition.Endothermic peaks that corresponded to relaxation enthalpy were observed for a β-lactoglobulin with 4 % moisture. Enthalpy and peak temperature increased on storage of β-lactoglobulin when it was held in the glassy state at different temperatures (20, 40, 60 º C). The general characteristics of the endothermic peaks were similar to those previously reported for synthetic polymers

Ohmic-Assisted Texture Softening of Cabbage, Turnip, Potato and Radish in Comparison with Microwave and Conventional Heating

Recently, ohmic heating has shown promising advantages for accelerated and controlled texture softening of some vegetables over conventional cooking. Textural properties of ohmically cooked cabbage, radish, turnip and potato were measured by texture profile analysis, and compared with microwave and conventional cooking. The data were experimentally modeled into an exponential model and softening rate and residual texture were calculated. Ohmic heating at 380V softened the texture of all four studied vegetables at greater rates in comparison with microwave and conventional methods. Comparing the texture softening rate, k value, of the cooked vegetables indicated that they were in the order of radish>turnip>potato>cabbage, and among the four studied vegetables the maximum and minimum texture response changes to cooking were found in radish and cabbage, respectively. In contrast to conventional and microwave cooking, an interesting and emerging finding was the significant increase in cohesiveness of ohmically processed vegetables with cooking time. Practical Applications: Ohmic cooking had recently been introduced as an emerging method to shorten cooking time and speed up texture softening of vegetables. In this research, four vegetables were cooked with ohmic technology and their textural properties were compared with the samples treated with conventional and microwave cooking. The results showed the ability of ohmic technology to soften the texture of vegetables faster than other methods with greater constant rate values and less residual textures. By applying ohmic processing, food industry can benefit from controlled texture modification of vegetables leading to higher textural quality of processed foods

Texture hysteresis of pistachio kernels on drying and rehydration

To prolong shell life, pistachio kernels are first dried and then in many cases they are rehydrated prior to or during food formulations. Texture of the rehydrated kernels is one of key organoleptic properties for consumer acceptability. In this research pistachio kernels were dried and then rehydrated to different moisture levels to compare the effect of these treatments on their textural properties. This was performed to examine texture differences between pistachio kernels of same water content but different drying, rehydration or thermal histories. Texture profile analysis data showed that hardness, gradient and compression energy of all pistachio samples increased with moisture reduction and significant differences were observed between the textural parameters of dried and rehydrated samples with same moisture level and lower values were obtained for rehydrated samples. It was evident from the results that thermal history of pistachio plays a key role in determining its textural and mechanical properties. Having pistachio kernels of same moisture and different drying and rehydration histories does not guarantee similar textural properties. These findings are clearly showing that texture deteriorations or changes can occur when fruits are first dried and then rehydrated to the initial moisture level. This can have practical implications in developing and designing foods with texture being their main sensory property

Ohmic-assisted hydrodistillation technology: A review

Volumetric heating techniques such as ohmic heating have emerged as alternatives to conventional processing methods for diverse applications in the food industry. One of the novel applications of ohmic heating is ohmic-assisted hydrodistillation (OAHD), which utilizes the volumetric heating benefits to overcome traditional distillation shortcomings. This technique proffers benefits such as saving time and energy and has gained increasing interest as a preferred approach for ethanol distillation and essential oil extraction from various plant materials. Scope and approach This paper reviews the principles and current applications of OAHD. The effects of OAHD on process time, energy consumption, and distillate quality are discussed. Considerations for industrial application of OAHD are highlighted and its salient drawbacks are also taken into account. Key findings and conclusions Advantages of OAHD over conventional distillation include high thermal efficiency, short processing time and reduced operational cost. Further research on safety and sustainability along with economic study are prerequisites for commercial application of this technology

Ice cream powder production and investigation of its rheological and organoleptic properties

A basic formulation (50 g sucrose + 47.5 g milk powder + 1.5 g cocoa powder) was mixed thoroughly with various proportions of xanthan, sodium alginate, tragacanth gum and carrageenan gums to make fifteen desired formulations of ice cream powder. The ice cream powders and water were poured into the ice cream maker machine in proportions of one to one (w/w) and ice creams were prepared and compared. Melting time, rheological and organoleptic tests on the produced ice creams were performed and the results showed that the maximum viscosity and melting time belonged to the number 7 and 14 samples, having tragacanth and carrageenan in their formulations, respectively. Overall, acceptability of the samples 1, 7, 8 and 14 was the highest. Using mixed combinations of hydrocolloids in ice cream powder formulation offers higher viscosity, longer melting time and better organoleptic properties to the final product (ice cream) than single hydrocolloids

Ultrasound assisted-viscosifying of kappa carrageenan without heating

The objective of this study was to evaluate viscosifying power of ultrasound waves on kappa carrageenan dispersions in water without using heat. After ultrasound treatment rheological characteristics of kappa-carrageenan dispersions in water were evaluated at 45 degrees C. Shear stress-shear rate and viscosity curves clearly indicated sharp increases in viscosity and consistency coefficient (k) of ultrasound treated dispersions with ultrasonication time up to a certain level (1-2 min). All ultrasonicated dispersions showed shear thinning flow behavior. Prolonged exposure of kappa-carrageenan dispersions to high-intensity ultrasonic waves produced a permanent reduction in viscosity, intrinsic viscosity and also relative molecular weight. Addition of KCl after ultrasonication was more effective in increasing viscosity compared to KCl addition prior to ultrasound treatment. Power ultrasound showed high potentials in solving some of traditional limitations related to solubility of hot water soluble biopolymers and may offer food and pharmaceuticals industries more options to benefit from a wider range of biopolymers