Assessing the effects of different prebiotic dietary oligosaccharides in sheep milk ice cream.

The objective of this study was to assess the effects of different prebiotic dietary oligosaccharides (inulin, fructo-oligosaccharide, galacto-oligossacaride, short-chain fructo-oligosaccharide, resistant starch, corn dietary oligosaccharide and polydextrose) in non-fat sheep milk ice cream processing through physical parameters, water mobility and thermal analysis. Overall, the fat replacement by dietary prebiotic oligosaccharides significantly decreased the melting time, melting temperature and the fraction and relaxation time for fat and bound water (T22) while increased the white intensity and glass transition temperature. The replacement of sheep milk fat by prebiotics in sheep milk ice cream constitutes an interesting option to enhance nutritional aspects and develop a functional food.

Effect of sodium reduction and flavor enhancer addition on probiotic Prato cheese processing.

The effect of partial substitution of NaCl with KCl and the flavor enhancers addition (arginine, yeast extract and oregano extract) on Probiotic Prato cheese processing with (L. casei 01, 7logCFU/mL) was investigated. Microbiological (lactic acid bacteria and probiotic counts), physicochemical (proximate composition, pH, proteolysis), bioactivity (antioxidant and angiotensin I-converting enzyme inhibitory activity), rheological (uniaxial compression and creep tests), water mobility (time domain low field magnetic resonance), microstructure (scanning electron microscopy) and sensory evaluation (consumer test) were performed. Sodium reduction and flavor enhancers addition did not constitute an obstacle to the survival of lactic and probiotic bacteria. Proximate composition, antioxidant and angiotensin I-converting enzyme inhibitory activity, and the rheological parameters were affected by the addition of flavor enhancer. No change in the fatty acid profile of cheeses was observed while good performance in the consumer test was obtained by the addition of yeast extract and oregano extract. Prato cheese can be an adequate carrier of probiotics and the addition of different flavor enhancers can contribute developing this functional product in the cheese industry.

Manufacture of Requeijão cremoso processed cheese with galactooligosaccharide.

The addition of galactooligosaccharide, (GOS, 0, 1.5, 3 or 4g/100g) on the quality parameters of requeijão cremoso was investigated. Chemical characteristics (pH, moisture, fat and protein), color (L*, a*, b*), water mobility by TD- nuclear magnetic resonance, rheology (flow curve and oscillatory tests), microstructure and sensory acceptance (consumer test) were evaluated. The addition of GOS provided a denser and compact structure and reduced number and size of fat globules. Increased GOS level (3 and 4g/100g) improved the softness and spreadability (decrease of G', G″ and apparent viscosity and an increase of tan δ and melting index) and impacted positively on the aroma and taste of the requeijão cremoso. Overall, the addition of GOS in requeijão cremoso was proved to be a potential and interesting technological option.

Determination of the centesimal composition and characterization of flours from fruit seeds.

Fruit seeds, common byproducts of the food industry, are generally discarded despite their potential use as a source of nutrients in the human diet. The dietetic use of the flour made from fruit seeds depends on their centesimal composition and other characteristics. In this work the centesimal compositions were determined of six fruits seeds. The flours obtained from these seeds were characterized by infrared absorption spectrometry, X-ray diffraction, thermogravimetric analysis, and low-field nuclear magnetic resonance. The protein content of the seeds ranged from a low of 10% (Surinam cherry) to a high of 32% (orange). The lipid content varied from 3% (Surinam cherry) to 39% (peach). The highest ash content was 3.9% (melon and peach). The X-ray diffraction analyses showed that the starches from jackfruit and Surinam cherry seeds presented A-type crystallinity and the thermogravimetric tests showed they were the most thermally resistant. The relaxometry studies of the hydrogen nucleus determined the mobility domains of each sample.

Determination of herb authenticity by low-field NMR.

The safe use of herbal medicines requires prior authentication of the raw materials used to make them. This is an important step, since the ingestion of herbal preparations or extracts can cause serious health problems. Among the different analytical techniques, nuclear magnetic resonance (NMR) spectroscopy has the advantage of being non-invasive and therefore suitable for the characterization of natural products such as medicinal plants. This work presents a characterisation study of the samples of the popular plant Maytenus ilicifolia, obtained from different commercial producers. This plant is used for the treatment of gastrointestinal disorders, as it possesses antitumorigenic, analgesic, anti-inflammatory and antioxidant properties. The differences in the chemical structure and molecular organisation detected by thermogravimetric analysis (TGA), infrared spectroscopy (FTIR) and nuclear magnetic resonance spectroscopy (NMR) were also investigated by proton nuclear magnetic resonance relaxometry, in particular by fast field cycling (FFC) relaxometry, and relaxometry in the rotating frame. All results confirmed the similarity between the control sample and only one of the plant investigated. The differences detected between the samples could be related to their non-authenticity, due to the non recognise the plant due to the leaves similarity among plants from the same family and/or contamination, due to addition of similar other plants parts to the commercial ones, as they are mixed together this difficulties the acceptation of the plant.