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Diacetyl and 2, 3-pentandione are important contributors to beer flavor. These two compounds are grouped and reported as the vicinal diketone (VDK) content of beer. The removal of diacetyl is an important step in the maturation of beer. Diacetyl is formed by oxidative decarboxylation of ?-acetolactate. In the next step of fermentation, diacetyl is transformed to acetoin by enzymatic complex of the yeast. For flavor profile of beer it is very important that the concentration of VDK to be less than flavor threshold. In brewery pilot plant from USAMV Cluj-Napoca production trials were performed to monitoring any influence on beer quality and to optimize saving in time and cost.

The present study includes researches regarding the composition of different varieties of rosemary essential oil. The essential oils were extracted from the plant material using the hydrodistillation technique. The analyses of the composition of essential oils were carried out by using a GC-MS system. The chemical constituents of the essential oil were separated and identified using the GC-MS NIST libraries.

This paper aims to present the researches carried on the sorghum (Sorghum vulgare Pers., sin. Sorghum bicolor (L), Moench). Based on the nutritional value relatively close to the other cereal beans used in man`s nourishment, the sorghum grains are on the future raw materials for the production of expanded cereals in the food industry. The research has been performed on the simple hybrid Fundulea 21, of the crop of the year 2001 by achieving the most adequate physical parameters for expanding: roasting time (factor A), steam pressure (factor B) and steam impregnation time (factor C). For the assessment of the factors influence throughout several graduations, we have used the EVOP statistical processing method and variance method. The best outcomes whereby the grain volume has increased by 34,13 times, have been obtained when combining the factors: A = 12 min., B = 10 atm., C = 5 min.

The present study includes researches regarding the losses of hop pellets bitter acids during one year of storage. There were found that the losses of bitter acids are different for each hop variety. The global content on alpha bitter acids was established by conductimetry. Using the HPLC method we were able to separate the different fractions of alpha and beta bitter acids. From the alpha/beta ratio the hop varieties can be distinguish.

It is a very complex and actual problem to assure a healthy and equilibrate feeding, because of the special importance that food has for human health. The acrylamide contamination of food products or the formation during the technological processes are among the main risk factors for public health owed to the potential to generate toxicity from this contamination with multiple noxious effects. Acrylamide is an instable organic compound, white crystals, odorless, water, ethanol and ether soluble. It has the composition, from chemical point of view, of an amide, with the chemical formula C3H5NO. Acrylamide is used in the plastic materials, paper, dyes, textile industry, also in construction and cosmetics etc. It is also used for making polyacrilamide, product used as water stabilizer and sewage water treatment and for gels electrophoresis.

Knowing the evolution of grapes maturity is of great importance in grapes and good quality and healthy wines. The ripening period has 2 limits – the beginning date and the end day – one cannot be precise about the optimal moment for harvest inside this period, which is usually 10-15 days of duration.