Gabonaminősítő módszerek fejlesztését megalapozó kutatások

Egy búzaalapú termék fejlesztésénél, minőségének stabilizálása során szükséges tudnunk, hogy milyen tényezők befolyásolják az adott minőséget. A minőségközpontú búzanemesítés is igényli a minőség-összetétel közötti kapcsolatok tisztázását, a befolyásoló tényezők hatásának megismerését. A nemzetközi gyakorlatban hasonló célra is különböző módszereket alkalmaznak, másrészt sok esetben csak kis mennyiségű minta áll rendelkezésre. A kutatómunka eredményei: - 30 fajtaazonos búzából készült liszt minősítését végeztük el valamennyi, nemzetközileg elfogadott vizsgálati módszerrel, illetve eszközzel, úgymint: Valorigráf, Farinográf és Mixográfos, Alveográf, nyújthatóság, Zeleny-index, esésszám, gyors viszkoanalizátor (RVA). Egyes paraméterek között szoros összefüggést tártunk fel. - Egyes vizsgálatokat a részben a Tanszéken kifejlesztett mikro-módszerekkel is elvégeztük. A validálás eredményei a mikro-módszerek alkalmazhatóságát bizonyítják. - Egyes adott fehérje alegységek, és azok aránya (Glu/Gli arány), valamint a technológiai paraméterek között összefüggés állapítható meg. - Az idegen fehérjék (pl. amaránt, hüvelyes fehérjék) általában rontják a hagyományos sütőipari minőséget, ami jórészt a fehérjeszerkezet különbözőségéből adódik. - Az eredmények véleményünk szerint a gyakorlatban is jól használhatók. Pl. a módszerek számának csökkentése, paraméterbecslés az összefüggések alapján; fehérje-alegységek beépítése a nemesítése során, illetve a mikro-módszer alkalmazása a gyakorlatban. | At the product development or in the breeding process, the knowledge about the relationship between the quality and the chemical composition is necessary. However, different methods are used for the determination of wheat or flour quality, depending on the goal of the utilisation, the tradition, or the accepted standards. In some cases ?like breeding, or R+D experiments- only limited amount of samples are available. The main results of this research work are the following: - The quality of 30 different wheat species was studied with all, internationally accepted methods: Valorigraf, Farinograf és Mixograph, Alveográph, Extensograph Zeleny-test, falling number method, rapid visco-analyser (RVA) vas used in studies. Sicnificant relationships were detected is some cases between different parameters. - Micro-methods were also used in cases of valorigraph, farinograph, extenzograph and Zeleny-test. These methods and instruments were partly developed at the Department. The results of validation established and confirmed the adaptability of the new procedures. - In some cases, relationships were found between given protein subunits or the rates of glutenin and gliadin, and the different measured parameters. - Usually, the addition of non-wheat proteins to the wheat flours decreases the quality parameters. The possible reason is the very different protein structure. - In our opinion, these results are also utilisable in the every-day practice

STUDY OF THE RHEOLOGICAL PROPERTIES OF MYOSIN-PLANT PROTEIN SYSTEMS DURING THERMOTROPIC GELATION

Model systems containing myosin mixed with native and slightly preheated plant protein preparations (soy glycinin, sunflower seed protein isolate, wheat gluten, wheat gliadin and wheat glutenin) and experimental sausages from beef meat and added protein preparations were studied after heat treatment for textural properties using an Instron 1140 apparatus. All non-meat preparations caused decrease in cohesivity and elasticity except glutenin. Vital gluten and soy glicinin had some advantages in comparison to sunflower seed protein. Preheating of gluten for 30 and 45 minutes resulted in significant increase in hardness and chewiness but not in elasticity. Preheating of soy glycinin for 45 minutes caused significant changes in work of compression, elasticity and chewiness

INVESTIGATION OF THE FOAMING PROPERTIES OF SOME FOOD PROTEIN PREPARATIONS

The foaming properties of 10 different protein isolates and protein preparations (wheat germ-, barley germ-, maize germ protein, lentil-, pea-, soy protein, ovalbumin, bovine serum albumin = BSA, casein and lysozyme) were investigated using volumetric and conductometric methods. According to the volumetric method casein and BSA had the best foaming power. Good foaming power was observed with maize germ-, soy-, pea-, barley germ proteins and ovalbumin. The foam forming ability of wheat germ protein and lysozyme was the lowest. On the basis of conductometric results the proteins investigated may be divided in to the same three groups: However, within the group some changes in the order of proteins may occur. In calculating the linear correlation between the two methods an improvement of correlation (r = 0.93) was achieved by modifying the evaluation of conductometric curves. Maize germ-, soy and lentil protein showed the best foam stability and barley germ protein the lowest one according to conductometric results. The correlation between the foam stability data obtained by the two methods is very poor

CONCENTRATIONS OF CITRATE AND KETONE BODIES IN COW´S RAW MILK

The milk composition of high-yielding dairy cows is highly related to their nutrition. The energy deficiency in dairy cows can cause subclinical or clinical ketosis. In ketotic state the concentration of ketone bodies (acetone, AC; acetoacetic acid, ACAC; and β-hydroxybutyric acid, BOHB) increases in the different body fluids and simultaneously, changes in concentration of other compounds are also expected. The authors´ hypothesis is that the members of the TCA-cycle, such as citric acid (CA) also change in association of increased formation of ketone body. To support this hypothesis the concentrations of ketone body components and CA were parallel measured and their relationship was studied in raw milk samples. Based on the AC concentration of the milk samples two groups were formed retrospectively: High Acetone (HA) Group (n=41) of AC concentration >0.4mM and Low Acetone (LA) Group (n=78) with the AC level ≤ 0.4 mM. In all samples very low ACAC level was found, which is a consequence of the spontaneous decarboxylation of ACAC to AC during the usual sample storage. Focusing on the results of HA Group the authors found significant relationship between CA and ketone bodies and a parallel drop of AC and CA during the metabolically crucial first 1-4 weeks of lactation. For this reason they suggest to introduce simple, easy, automated methods to determine AC and/or CA concentration in raw milk

A számítógéppel támogatott adaptív oktatási környezet megvalósítása

Adaptive learning management methods and education strategies are integral parts of the efforts in school development nowadays. Several school innovation programme use different methods in the daily teaching and education progress in order to realize the dif-ferentiation in the education of students. Nevertheless, it is important to consider the re-quirements of the recent school system in connection with the content of the learning materials and learning management methods. The enhancing of development of students' ICT skills allows using computer individually for students. Computerized Adaptive Test-ing (CAT) may become a part of students' daily work inside and outside classroom, sup-porting the improving of curricular performance.Adaptive learning management methods and education strategies are integral parts of the efforts in school development nowadays. Several school innovation programme use different methods in the daily teaching and education progress in order to realize the dif-ferentiation in the education of students. Nevertheless, it is important to consider the re-quirements of the recent school system in connection with the content of the learning materials and learning management methods. The enhancing of development of students' ICT skills allows using computer individually for students. Computerized Adaptive Test-ing (CAT) may become a part of students' daily work inside and outside classroom, sup-porting the improving of curricular performance