S & TA & NU. Rivista di scienza e tecnologia degli alimenti e di nutrizione umana最新文献

Onions of "Dorata di Parma" variety were exposed to 10 Krads of Co60 gamma irradiation in 5, 10, 20, 40, and 80 minutes in December, 1975 and then stored in the cold storage (10 +/- 1 degree C; R.H. 65-70%) and at the room temperature (15-20 degrees C; R.H. 40-70%) for 3 months, to study the influence of dose-rate and post-harvest period of treatment. Average number of buds sprouted in each onion bulb under cold storage condition ranged from 2-3, while this number was found to increase to 3-4 under ambient storage conditions. Although no effect of either irradiation or dose rate was observed when onions were irradiated after the break of their dormancy, however, a significant slowing down effect of irradiation could be observed as far as the rate of growth of sprouts was concerned. Weight loss was also reduced significantly in the irradiated onions as compared with controls.

The research conducted to verify the presence and the amount of residues of organophosphorus insecticides in olive oil from olive trees sprayed against. Dacus oleae has shown that both hydrophilic (dimethoate, formathion, phosphamidon) and lypophilic (fenthion, medathion, prolate) substances tested leave more or less appreciable residues in the oil, either in a short time or in more than one month from the treatment. In the operative conditions reflecting antidacic practice, the amount of residue appears higher for the lypophilic organophosphorus insecticides.

Toxic activities in various animal species have shown for rapeseed oil. In this paper the influence of this oil on lipoprotein lipase activity of heart, liver and lung of pigs has been examined. The animals were fed with rapeseed oil with 40% erucic acid for 7, 15, 20 and 40 days. The control animals received olive oil. The results have shown a slight increase in the lipoprotein lipase activity in the heart of the pig after 20 days with rapeseed oil. In the liver this increase is particularly large in the pigs having been fed for 15 days both with rapeseed oil and olive oil. No differences were observed in the lung in the test and control animals with the only exception of animals fed for 20 days.

Phospholipids are receiving a burst of increasing interest in biological and medical sciences. The change in perspective toward these compounds is largely due to the better knowledge we now have on biological membranes and to the increased technical tools available.

The determination of lipids, available carbohydrates and unavailable carbohydrates, and of various minerals has been carried out on some baby foods; the value of the protein fraction has been similarly determined by the ultrafiltration method of the enzymic hydrolisate in vitro. Both the total protein content and the essential amino acid availability of the foodstuffs are satisfactory although generally speaking a slight decrease of the protein value has been found in this material as compared to the crude samples, due particularly to the breakdown of sulfur-containing amino acids. This breakdown is due probably to the high temperature reached during the technological processes at industrial level.

40 wistar rats were divided into two groups which had been fed one year earlier a diet in which 30% of the caloric intake consisted of rapeseed oil and peanut oil respectively. Both groups were then fed a diet of 30% peanut oil for five months and then fed a normal diet for seven months. At this time each of the two main groups was subdivided into four smaller groups, each group receiving a different diet: one of 25% rapeseed oil, one of 25% peanut oil, one of 25% butter, and one internal control group. At the end of the experiment the rats were sacrificed by decapitation. One portion of each heart was used for measuring its fatty acid content and the remaining portion was used for preparing sarcosomes on which the exigen consumption was measured polarographically. It was found that no erucic acid was present in the hearts of the rats fed rapeseed oil one year previously, and then then refed the same diet in the present experiment. The mitochondrial respiratory activity of the treated rats did not show any significant difference with respect to the found in the control groups, unlike the first experiment.

Biological activity of microorganism is related to water activity (aw). In this paper the effect of glicerol as humectant on Saccharomyces cerevisiae viability was considered. The irreversible loss of viability was observed only for values inferior than 0,75. The K+ presence promoted an increasing of cell viability and growth. We have evaluated the changes of the most important components of cell poll; the increasing of glicerol amount of the system induced a drastic fall of aminoacids, purines and K ions content, but it increased the Na ions content. The exposure of cells to increasing glicerol concentrations, caused an aminoacids and purines excretion related to contact time; after a few hours this material was readsorbed by cells.

Use of near infrared radiation as heating source in freeze drying of food products, appear to be interesting both for the efficiency of the process and for its economical aspect. In the present paper the results obtained in freeze drying runs with heating plates and I.R. radiations are described. The obtained results show that: with increasing trays load of product, the I.R. system is more efficient than the traditional one; the product quality obtained is higher for I.R. radiation, especially with higher tray loads; the heat flux output of the I.R. system is much lower than the one of the heating plates, at the same level of subliming water.

Capsaicin is extracted from dried powdered pepper by 2-propanol in Soxhlet, separated by TLC on Silica gel, developing with petroleum ether (40-60 degrees C PB), chloroform and acetonitrile (40:45:15) mixture and spectrophotometrically estimated at 280nm. The method appears to be accurate and suitable for routine analysis.