فصلنامه پژوهش و نوآوری در علوم و صنایع غذایی
سال سوم شماره 4 (زمستان 1393)

In this study, Clash Voice processing in the field of wavelet and Artificial neural network (ANN) has been evaluated in order to separate hazelnuts according to their size (large, small, medium), and also being filled or empty. Hazelnuts were divided into three size groups (large, medium and small) and each hazelnut of the groups was weighted in order to separate the filled ones from the empty ones. All hazelnuts were then released from 40 and 50 cm height; bopped with a metal plate and Clash Voice was recorded. Signals in the field of wavelet were processed after the Preprocessing. Obtained profiles were applied as input to the ANN. The results showed that Neural Networks with 3 and 9 neurons in the hidden layer could successfully (accuracy of 100%) break up the hazelnuts that were dropped from 40 and 50 cm heights. The filled and empty hazelnuts of large, medium and small groups were separated from each other with the accuracy of 100, 99.61 and 98% for the height of 40 cm and 100, 99.66, 97.5% for the height of 50 cm. This research in combination with the common methods could probably reduce damages; increase the precision and the speed of separation.

Doughnut is a special fermented and fried snack. There are a few studies about wheat flour fortification with soy protein isolate to produce doughnut. The present research was done to study the effect on quality features of doughnut during preservation. Partial substitution of wheat flour with soy protein isolate at the levels of 0, 1, 2 and 5 g/100 g was carried out to determine its influence on quality characteristics of doughnuts. The water absorption and protein content of the samples were measured by Farinograph and kjeldahl method respectively. Quality characteristics of doughnut such as porosity and color were determined with Image J software. Sensory evaluation of doughnuts was carried out on 9-point hedonic scale by a panel of 12 judges.The protein content and water absorption of the fortified samples were higher, but their Volume, porosity and lightness were lower than the control. Control sample had the highest overall acceptability rating although the difference between samples were not significant (P>0.05). So it is possible to produce a doughnut fortified with 1-5% soy protein isolate with higher protein content without having significant negative effect on its acceptability.

In recent years, biopolymers have been considered as a good replacement for plastic materials from petroleum derivatives in the field of packaging. Therefore, the purpose of this research was to evaluate biodegradable edible films produced by a Persian gum. In this study, Charkhak gum and sorbitol, glycerol and polyethylene glycol 600 were used as plasticizer in four concentrations of 30%, 32/5%, 35% and 37/5% were used to prepare edible films by means of casting approach. Preliminary experiments showed that the Charkhak gum was not blended with polyethylene glycol 600 to form a film with polyethylene glycol 600.The results of ANOVA test demonstrated that an increase in the concentration of plasticizers caused anincrease in oxygen and water vapor permeability and elongation of the films; on the other hand, tensile strength, Young's modulus and surface roughness of the film decreased. Moreover, it was found that water vapor (significantly) and oxygen permeability and extensibility (not significantly) of sorbitol films was lower than glycerol films, however, its surface roughness was more than glycerol films (P<0.05). Thus, considering these parameters, the films containing 30% sorbitol as plasticizer were the best films, because they had the minimum amount of water vapor and oxygen permeability (0.49 g.m/m2/Pa.s and 3.7 respectively) and highest mechanical strength among all films, while having good elongation characteristics.

Mannoprotein is a glycoprotein consistency of a poly mannose backbone covalently attached to a protein moity. It was extracted and purified from the cell wall of Kluyveromyces marxianus yeast. After having determined a number of its properties, the influence of mannoprotein (0.25, 0.5, 0.75, 1, 1.25 and 1.5 % W/V) on the formation and stability of ultrasonically prepared emulsion (ratio 20:80 % W/W) was studied and changes in the quality attributes of samples during 1, 7, 14, 21 and 28 days were monitered. The results indicated that surface and interfacial tensions decreased significantly by increasing mannoprotein from 0.25 to 1.25. The Surface electrical charge of dropes, however, increased with concentration. The drop size distribution curves were found to be monomodal for all samples and appeared noticeably sharp at 1.25%. Storage of emulsions samples for a period of four weeks led to a significant increase in the size of droplets particularly in the samples containing 0.25 until 1% mannoprotein,while negligible changes were observed of higher concentration. The results rheological flow properties were showed increasing mannoprotein concentration leading to decreased flow behavior index and increased the apparent viscosity and consistency index of all samples. In addition, the flow behavior of emulsion samples were had to be non-newtonian and shearthinning.

In active packaging, active agent can change organoleptic properties of food or package condition. Objective of this study was to determine effect of active packaging and absorber agent on optimum shelf life condition of button mushroom (Agaricus Bosporus). Two type of packaging, stretch Polyvinyl Chloride and Biaxially oriented polypropylene, and four type absorbers, silica gel 1.25 g, silica gel 2.5 g, silica gel 1.25 g with sodium chloride 1.25 g, silica gel 1.25 g with foam, on quantitative and qualitative properties of button mushroom were considered. The qualitative result showed that Biaxially oriented polypropylene and control and silicagel 1.25g had lowest loses weigh. The maturity index results showed that silica gel 1.25 g and 2.5 g with Biaxially oriented polypropylene had significantly higher score than all other samples and they had best rating after 8 days. The lowest rating was for polyvinyl cholorid film and mix treatments after 16 days.

The effects of coating from chitosan incorporating green tea extract on lipid oxidation, fungal growth and sensory properties of walnut kernel were studied. The green tea extract obtained from green tea (GT) and chitosan (C) powder were combined to obtain the final concentrations of C-GT: 5-0, 5-5, 5-10, 10-0, 10-5 and 10-10 gram per liter in aqueous coating solution. Effective inhibition of lipid oxidation and fungal growth during storage of walnut kernel (18 weeks) was possible through Chi10 coating combined with GT. Different proportions of GT had no significant effect (P< 0.05) on lipid oxidation. Regarding the C10 with different proportions of GT, fungal growth was not detected during storage period. Throughout the storage, coating without GT showed no significant (P< 0.05) effect on sensory properties, however Chi10-GT10, was significantly (P< 0.05) unacceptable by the panelists. The results suggested that Chi10- GT5 could prolong the shelf life of walnut kernel.

The purpose of this research was to produce a chocolate dessert (based on foamed systems) with desirable characteristics. In this study the effect of different concentrations of three proteins including albumin (1, 2, and 3 g), sodium caseinate (1, 2, and 3 g), whey protein concentrate (1, 2, and 3 g) as foaming agents and gelatin (1, 2, and 3 g) as a stabilizer, on sensorial, physical and textural properties of chocolate mousse were evaluated and the correlation between the sensorial parameters were also determined. The results showed that the samples containing 2 g of gelatin had higher acceptance. The density was in the range of 0/721 to 0/927g/cm3. Samples including albumin had lower density than the samples prepared with sodium caseinate and whey protein concentrate. The sample which contained 3 g of gelatin and 1 g of whey protein concentrate showed the lowest gas hold up (6/44), and the sample which contained albumin had the highest of this parameter. The Maximum amount of springiness was 1/09 mm in the sample which contained 3 g of albumin and 3 g of gelatin. The sample which contained 3 g of whey protein concentrate and 3 g of gelatin showed maximum of chewiness (0.178 N.m).