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Royal jelly (RJ) is a beehive product that has gained a significant scientific and commercial interest due to its healthy properties. In the present study, lipid content, fatty acid profile and phytosterol amount were determined in eight local and four commercial pure RJ samples. A mixture of diethyl ether/isopropanol 50/1 (v/v) was chosen to extract fat matter from RJ. Lipid amounts ranged from 2.3 and 7.2 % and from 2.0 to 3.2 % of the fresh product in local and commercial RJ, respectively. Fourteen fatty acids and three phytosterols were identified. About 70 % of the total fatty acids consisted of (E)-10-hydroxy-2-decenoic and 10-hydroxydecanoic acid. No significant difference was observed between local and commercial samples in regards to the relative amount of individual fatty acids. Sterols were in the range 179-701 and 329-1,097 mg kg -1 of fat in local and commercial RJ, respectively. A significant difference (p B 0.05) was observed within RJ types in regards to the 24-methylenecholesterol fraction, amounting to 77 and 67 % of identified sterols in local and commercial products, respectively.

Sixty-five strains of lactobacilli isolated from salami were tested for their antifungal activity in early and late phases of growth. Ten strains showed inhibitory activity in the early phase of growth towards moulds such as Aspergillus and Penicillium. The active compounds identified were phenyl-lactate and hydroxy-phenyl-lactate. All strains tested had activity in the late phase, after autolysis. The compounds released were peptidic and showed antifungal activity.

The combined effect of starter culture, nitrites, and nitrates has been studied in low-acidity salamis, typical products of northern Italy. Nine batches have been prepared, combining three different inoculations of starter cultures (control, Lactobacillus plantarum , and Lactobacillus plantarum together with Kocuria varians ) with three different preservatives (control, sodium nitrate, and sodium nitrite). All of the batches showed a good fermentation process with a proper pH decrease, which was quicker in batches inoculated with L. plantarum. The use of starter cultures and in particular the use of nitrites allowed the control of the proliferation of Enterobacteriaceae and enterococci. The accumulation of biogenic amines, especially putrescine, cadaverine, tryptamine, and tyramine, in salami ready for consumption (60 days of ripening) was strongly affected by the presence of Enterobacteriaceae and enterococci. Results obtained showed that the combined use of adequate preservatives and starter cultures allows the production of safer products with improved sensorial profile.

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