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Influence of acetylated distarch adipate on some rheological properties of ketchup
2002
Fortuna, T. | Juszczak, L. | Stachura, M. (Agricultural University, Krakow (Poland). Dept. of Analysis and Evaluation of Food Quality)
Ketchups with the same percentage addition of different acetylated distarch adipates were found to have different rheologival properties. A non-Newtonian pseudoplastic behaviour with tixotropy was characteristic of the examined ketchups. The values for particular parameters of the rheological models and the surface area of hysteresis were dependent on the starch preparation used
Показать больше [+] Меньше [-]Physico-chemical properties of oxidized starches of different origin
2002
Fortuna, T. | Juszczak, L. | Pietrzyk, S. | Wrobel, M. (Agricultural University, Krakow (Poland). Dept. of Analysis and Food Quality Evaluation)
The native starches of potato, wheat, tapioca and waxy corn were oxidized with sodium chlorite in the presence of formaldehyde. The initial and modified starches were examined for the content of carbonyl and carboxyl groups, phosphorus and amylose, and for reduction capacity, water absorption, solubility in water and pasting characteristics. The results showed that the process of starch oxidation caused the changes in some physico-chemical properties of the modified starch preparations. Wheat starch was the most susceptible to oxidation with sodium chloride in the presence of formaldehyde, whereas waxy corn starch was the most resistant to the oxidation. The oxidized starches had lower content of total phosphorus and higher reduction capacity. The preparations of oxidized starches had lower maximum viscosity than initial starches
Показать больше [+] Меньше [-]Porosity of starch granules of different origin
2002
Juszczak, L. | Fortuna, T. (Agricultural University, Krakow (Poland). Chair of Analysis and Evaluation of Food Quality) | Wodnicka, K. (University of Mining and Metallurgy, Krakow (Poland). Chair of General Ceramics)
The helium apparent and bulk densities were determined for ten types of starch. On the basis of the results obtained, the porosity and volume of opened pores in starch granules and starch beds were calculated. The highest values for porosity and total volume of opened pores were characteristic of oat and tapioca starches, whereas triticale, rye and potato starches had these values the lowest. In the case of wheat and potato starches, the porosity of the closed type was shown
Показать больше [+] Меньше [-]Relationship between sensory attributes, hidden attributes and price in influencing consumer perception of organic foods
2002
Brennan, Charles S | Kuri, Victor | Powell, Jane | et al.
This report was presented at the UK Organic Research 2002 Conference. Consumer attitudes to foods are mainly influenced by quality attributes. Ethical factors are important in some cases, but they may be overstated. The relationships between consumers' awareness of organic food, price and perceived quality of food were investigated by tests involving series of consumer panels and sensory evaluation. Sensory responses were also matched to instrumental analysis data. Results indicated that overall there was no relation between panellist’s views about organic foods and their sensory perceptions. Eighty percent of the panellists felt that organic products were too expensive, but would buy them if they were cheaper. However the study showed that most of the people would not be likely to change their preference once they had made a product choice based upon sensory attributes. This has important implications, indicating that not only price, but also sensory quality of organic food must be considered in order to maintain repeated purchases by most consumers.
Показать больше [+] Меньше [-]Results of routine testing of organic food for agro-chemical residues
2002
Lo, Ming | Matthews, Dave | Powell, Jane | et al.
This report was presented at the UK Organic Research 2002 Conference. Consumers expect organic foods to be free of agro-chemical residues. Organix Brands plc. routinely test organic food ingredients for agrochemical residues using independent test laboratories. In the past year 243 batches of ingredients were tested and low levels of agro-chemical residues were found in 21% of samples. These residues can arise in organic food through environmental contamination, processing contamination or even the fraudulent use of agro-chemicals on organic food. Food containing agro-chemical residues can enter the organic system because of limitations in the organic rules
Показать больше [+] Меньше [-]The influence of production method on the content and composition of lipid-protein complexes in UHT milk
2002
Kuncewicz, A. | Michalak, J. (University of Warmia and Mazury, Olsztyn (Poland). Inst. of Commodities Science and Food Quality Evaluation) | Panfil-Kuncewicz, H. (University of Warmia and Mazury, Olsztyn (Poland). Inst. of Dairy Science and Technology Development)
As a result of heating teratment novel lipid-protein complexes defined as proteolipids are formed in milk. The applied method of sterelization was found to have no significant effect on the level of these complexes in UHT milk. Further studies proved that the UHT milk sterelization system has a significant influence on lipids and proteins content in lipid-protein complexes. The composition of lipid and protein parts of proteolipids in raw milk and UHT milk is similar. The analysis of these structures showed the presence of such proteins as alpha-S1-casein, beta-casein as well as beta-lactoglobulin and alpha-lactoglobulin. The studies showed that fatty acids composition of fat from proteolipids of the milk does not differ significantly from that of milk fat
Показать больше [+] Меньше [-]Laboratory evaluation of legume quality
2002
Paul, Christian | Alex, Merle | Sölter, Ulrike | Tuori, Mikko | Hellämäki, Maria | Nousiainen, Juha | Lister, Sue
Parameters for apple quality and an outline for a new concept of quality
2002
Huber, Machteld | Powell, Jane | et al.
This report was presented at the UK Organic Research 2002 Conference. The commonly used concept of quality in relation to food, with its emphasis on external appearance and nutritional content is not sufficient for organic products and their market. In response a quality concept known as ‘vital quality’ has been developed based on the life processes (growth and differentiation) and corresponding product attributes (vitality, structure and coherence). The research project presented is based on the evaluation of the quality of apples, specifically cultivated for the research project with variation in picking date, bearing, sun exposure, bio-dynamic preparations and ageing after storage. Quality measurements included traditional methods used routinely to assess apple quality and also experimental parameters which are expected to be relevant for vital quality. The experimental parameters appeared to supplement the traditional parameters in a consideration of quality. The concept of ‘vital quality’ is a valuable one for the consideration of wider aspects of quality within organic farming systems and should be further developed
Показать больше [+] Меньше [-]Evaluation of infant formula protein quality
2002
Colić Barić, I. | Panjkota Krbavčić, I. | Pedisić, S.
Infant formulas are designed to simulate not only the content but also the performance of human milk as much as possible in order to be an adequate replacement of human milk. The most common sources of protein in infant's formula are either cow's milk or soy protein (isolate). From this point of view the aim of this study was to determine the nutritive value of these proteins sources in powdered infant formulas present in the Croatian market. Protein quality has been evaluated in vivo - feeding young growing rats, and in vitro by multienzyme systems. The results showed that protein digestibility (D) of both formulas are high and not significantly different according to methodology (in vivo and in vitro). Biological value (BV) and net protein utilisation (NPU) of milk protein based formula are lower than that found in the literature. The same bioassays for soy protein isolates based formula are extremely low, while PER and NPR values are higher than that of proteins in milk based formula. The data indicate that protein qualities of both powdered infant formulas evaluated in vivo are not satisfying and can not provide nutritional support to healthy infants. At this point further investigations should be done in order to identify the factors affecting protein quality.
Показать больше [+] Меньше [-]Development of a multi-nutrient data quality evaluation systems
2002
Holden, J.M. | Bhagwat, S.A. | Patterson, K.Y.
The U.S. Department of Agriculture's (USDA) Nutrient Data Laboratory (NDL) has redesigned the software of the USDA Nutrient Databank to provide a system for data acquisition, compilation, and dissemination, and as part of this system has developed a module to facilitate the evaluation of analytical data quality. USDA's first data evaluation procedures were developed as a manual system to assess the quality of analytical data for iron, selenium and carotenoids in foods. These procedures have been modified and expanded for multi-nutrient data quality evaluation. The same five evaluation categories; sampling plan, number of samples, sample handling, analytical method and analytical quality control, from the original work have been maintained but the evaluation questions have been made more objective. The rating scales for each category have been changed from discrete steps to a more continuous scale. These ratings are combined to give a Quality Index (QI), and Confidence Code (CC) that is disseminated with the nutrient data to indicate the level of confidence in the value. The algorithm for combining ratings from the five categories was revised from earlier systems to avoid the possibility that the aggregation of several mediocre data points would together, merit the highest CC.
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