16 research outputs found
Quality of Root Vegetables during Prolonged Storage
The objective of this study was to develop postharvest techniques and technologies of the most important root vegetables: carrots, celeriac and parsnip. Investigations included the effect of harvest maturity (harvest at November or January) and postharvest washing treatments (hot water, H2O2 and NaOCl and non-washed-control) of carrots (Daucus carota ’Bolero F1’), parsnip (Pastinaca sativa ‘Banatski dugi’) and celeriac (Apium graveolens var. rapaceum ‘Mentor’) roots and effects on their quantitative and qualitative changes during different storage conditions (S-1; 0°C and 98% RH or S-2; 0-2°C and 85-92% RH). Water loss and quality changes in these vegetables roots were monitored after 120 and 180 days of storage period (SP). At the end of SP the percentage of water loss ranged from 3.20% (from first harvest inside the S-1 with H2O2 treatment) in carrot to 39.29% (from first harvest inside the S-2 in control) in celeriac root. The dry matter content (DM) increased during storage period. Total sugar content (TSC) in the roots depends on year and harvest time. During SP, total sugar content increased more in S-2 cooling room. The parsnip root was characterized by more hardness texture relative to the carrot and celeriac roots. During SP carrot root loses the flexibility. The most effective method of maintaining quality of root vegetables is optimal harvest time followed by prestorage washing treatments (H2O2 or NaOCl) and storage at optimum temperature (0 ºC) with a high relative humidity 98%
The influence of drought on the occurrence of aflatoxins in maize
In this study, a total of 78 maize samples harvested during September and October 2012 in Vojvodina were analyzed. Presence of aflatoxins (AFs) was determined by enzyme-linked immunosorbent assay (ELISA) method. Among the 78 analyzed maize samples, even 44 (56.4%) samples were contaminated with AFs. Concentration interval between 1-10 μg/kg, 10-50 μg/kg and 50-80 μg/kg were found in 23.1%, 17.9% and 15.4% of analyzed maize samples, respectively. It was supposed that prolonged drought during spring and summer of 2012 had a great influence on high contamination frequency and concentration of AFs. [Projekat Ministarstva nauke Republike Srbije, br. III 46001
Analysis of interrelations between wheat protein fractions composition and its technological quality by combined multivariate and univariate statistics
Data on protein fractions' proportion, obtained with RP-HPLC and technological quality parameters for 29 wheat cultivars grown in Serbia and Croatia, were used for studying of interrelations among wheat protein fractions with different solubility and molecular weight properties by multivariate (PCA) analysis. Obtained trends were used as the base for investigations related to differentiation of technological quality among wheat cultivars with different combination of protein fractions' compositions using univariate statistics (ANOVA followed by Duncan's test) in order to draw out information about interrelations between protein fractions proportion in wheat cultivars and their technological quality. Analysis based on the first four PCA factors (89.04% of variability) pointed out interdependencies between: 1) high content of albumins and globulins, low gliadins content and gliadins/glutenins ratio, high omega-gliadins, LMW glutenins and low alpha-gliadins share in total protein with low water absorption, high energy and high resistance to extensibility ratio, 2) high albumin and globulin content and high proportion of omega-gliadins in total protein and low extensigraph extensibility, 3) high share of high molecular weight glutenins (HMW-GS) in total proteins, high extensigraph resistance/extensibility ratio and 4) high gamma-gliadins share in total protein and low extensigraph resistance/extensibility ratio
Effects of Wheat Bug ( Eurygaster
The effects of wheat bug infestation (Eurygaster spp. and Aelia spp.) on the composition of wheat gluten proteins and its influence on flour technological quality were investigated in the present study. Wheat samples of six wheat varieties, collected from two localities in northern Serbia, were characterized by significantly different level of wheat bug infestation. Composition of wheat gluten proteins was determined using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS PAGE), while the selected parameters of technological quality were determined according to standard and modified empirical rheological methods (Farinograph, Extensograph, Alveograph, and Gluten Index). The surface morphology of the selected samples was viewed using scanning electron microscopy (SEM). Wheat from wheat bug-infested locality regardless of the variety had deteriorated technological quality expressed with higher Farinograph softening degree, lower or immeasurable Extensograph energy, and Alveograph deformation energy. The most important changes in the gluten proteins composition of bug-infested wheat were related to gliadin subunits with molecular weights below 75 kDa, which consequently caused deterioration of uniaxial and biaxial extensibility and dough softening during mixing
The application of natural organic compounds in bakery industry
Investigations include the analysis of the impact of commercial products: complex additive (0.1, 0.3, and 0.5%), L-ascorbic acid (0.002, 0.004 and 0.012%), diacetyl ester of tartaric acid with monoglycerides (DATEM E472e, 0.1, 0.3, and 0.5%), α-amylase (0.002, 0.006 and 0.012%), xylanase (0.004, 0.012 and 0.024%), alcohol extract of rosemary, thyme or sage (0.5, 1.0 and 2.0%), as well as the combination of complex additive and rosemary, thyme and sage extract on rheological characteristics of dough. The study includes amylograph, farinograph and extensograph analysis of dough with and without additives (control sample). The volume of lost CO2 gas (mL) is the lowest in dough samples with an added combination of complex additive and thyme extract (0.05 and 0.5%) and rosemary extract (2.0%). In the samples with thyme extract (1.0%) added, the volume of lost gas is at a level of samples with added complex additive, DATEM, and L-ascorbic acid
Postharvest Practices for Organically Grown Products
Quality of produce cannot be improved after harvest, only maintained. Postharvest handling depends on the specific conditions of production, season, method of handling, and distance to market. Under organic production, growers harvest and market their produce at or near the peak ripeness more commonly than in many conventional systems. Organic production often includes more specialty varieties whose shelf life and shipping traits are reduced or even inherently poor. Harvesting and handling techniques that minimize injury to the commodity, as well as increased care with field and packinghouse sanitation, (chlorine, ozone, calcium hypochlorite, sodium hypochlorite and chlorine dioxide, acetic acid, peroxyacetic acid, vinegar, ethyl alcohol, hydrogen peroxide, etc.) during postharvest processes are vital components of a postharvest management plan for organic products. Sodium carbonate, sodium bicarbonate, and physical treatments such as heat treatments (as hot water treatment or dips, short hot water rinsing and brushing or hot air) can significantly lower the disease pressure on the harvested commodities. These sanitation practices are very easy to implement in the organic food production chain. They start in the field and continue during harvesting, sorting, packing, and transportation and continue even in the consumer’s home. All those treatments reduce rot development, provide quarantine security, and preserve fruit quality during cold storage and shelf life. In addition, the use chitosan, propolis, methyl jasmonate, essential oils, carnuba wax, biocontrol agents and modified atmosphere packaging can also reduce decay development during prolonged storage. All these treatments can be applied alone or in combination with each other in order to improve decay control after harvest and provide a healthy and safe product to the consumer. The aim of this chapter is to shed more light on the latest information on permitted treatments for organic products and on the possible mode-of-action of these treatments. This chapter summarizes technologies developed over the past five years that explore special physical treatments applied either directly, or in combination with other means to control rot development and insect infestation on fresh produce
THE APPLICATION OF NATURAL ORGANIC COMPOUNDS IN BAKERY INDUSTRY
Investigations include the analysis of the impact of commercial products: complex additive (0.1, 0.3, and 0.5%), L-ascorbic acid (0.002, 0.004 and 0.012%), diacetyl ester of tartaric acid with monoglycerides (DATEM E472e, 0.1, 0.3, and 0.5%), α-amylase (0.002, 0.006 and 0.012%), xylanase (0.004, 0.012 and 0.024%), alcohol extract of rosemary, thyme or sage (0.5, 1.0 and 2.0%), as well as the combination of complex additive and rosemary, thyme and sage extract on rheological characteristics of dough. The study includes amylograph, farinograph and extensograph analysis of dough with and without additives (control sample). The volume of lost CO2 gas (mL) is the lowest in dough samples with an added combination of complex additive and thyme extract (0.05 and 0.5%) and rosemary extract (2.0%). In the samples with thyme extract (1.0%) added, the volume of lost gas is at a level of samples with added complex additive, DATEM, and L-ascorbic acid. SCIENTIFIC PAPER UDC 664.6:66.022.3 DOI: 10.2298/HEMIND100709046
The dynamics of the fermentation process and sensorial evaluation of sauerkraut, cultivar Futoški and hybrid bravo-comparative study
Preservation of foods by fermentation is a widely practiced and ancient technology. Lactic acid bacteria because of their unique metabolic characteristics are involved in many fermentation processes of milk, meats, cereals and vegetables. The fermentation of white cabbage into sauerkraut traditionally proceeds in the presence of salt. White cabbage, cultivar Futoški has protected geographical origin according to domestic legislations because of its specific physical and sensory characteristics, as native as well as sauerkraut. The objective of this study was to follow the dynamics of biofermentation parameters for white cabbage, cultivar Futoški and hybrid Bravo. These two varieties were spontaneous fermented traditionally with addition of salt in concentrations of 2%. Fermentation process was conducted under anaerobic conditions at temperature of 18oC. Organic acids and pH were determinate in defined time intervals during fermentation process. Cabbage heads were also sensorially evaluated in native form before the beginning of fermentation as well as sauerkraut. Sensory evaluation was performed by 4 trained panelists in four measurements. Experiment showed that white cabbage, cultivar Futoški has more acceptable sensory characteristics and faster achievement of completion of fermentation of cabbage tissue
Sensory and color properties of dietary cookies with different fiber sources during 180 days of storage
The aim of this study was to examine the sensory properties of dietary cookies produced with addition of different dietary fiber sources (inulin and ligofructose, oat flakes, mixture of oat flakes and wholemeal flour, wholemeal flour and mixture of wholemeal flour and carob flour), and to measure instrumentally color changes of cookies upper and lower surfaces, after storage at temperatures of 18-20°C for 180 days. Addition of inulin and oligfructose was determined to be the fiber source with the highest impact on sensory properties. Storage for 180 days expressed the highest influence on texture properties of dietary cookies regardless of applied dietary fiber source. Color differences calculated from measured color properties (psychometric light, L*, psychometric tone, a*, and psychometric chrome, b*) between products including different fiber sources were noticeable to extremely noticeable among products, with the most expressed difference registered for products containing carob flour
Activation of waste brewer's yeast Saccharomyces cerevisiae for bread production
The waste brewer's yeast S. cerevisiae (activated and non-activated) was compared with the commercial baker's yeast regarding the volume of developed gas in dough, volume and freshness stability of produced bread. The activation of waste brewer's yeast resulted in the increased volume of developed gas in dough by 100% compared to non-activated brewer's yeast, and the obtained bread is of more stable freshness compared to bread produced with baker's yeast. The activation of BY affects positively the quality of produced bread regarding bread volume. The volume of developed gas in dough prepared with the use of non-activated BY was not sufficient, therefore, it should not be used as fermentation agent, but only as an additive in bread production process for bread freshness preservation. Intense mixing of dough results in more compressible crumb 48 hrs after baking compared to high-speed mixing