Browsing by Subject "Lipid oxidation"

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    Effect of the addition of tomato paste on the nutritional and sensory properties of mortadella
    (Elsevier, 2012-08-27) Doménech Asensi, Guillermo; García Alonso, F.J.; MartÍnez, E.; Martín Pozuelo, G.; Bravo, S.; Periago Caston, M.J.; Santaella-Pascual, Marina; Enfermería
    The aim of this study was to evaluate the effect of the addition of tomato paste (TP) to sausage mortadella in order to improve the nutritional properties and reduce the lipid oxidation associated with the content of lycopene. First, three different mortadellas without colourant were made with 2,6 and 10% of TP, to optimise technologically the amount of this ingredient. Then, commercial product was compared with 10% of TP mortadella; both products were made with natural colourant. After a proximate analysis only total protein decreased due to the addition of TP. Lycopene content in mortadella and the total antioxidant activity were proportional to the amount of TP added. The presence of TP provided stability during meat grinding, cooking and storage of mortadella by reducing the lipid oxidation. In addition, TP provided yellowness and softness; however, when TP was added together with red colourant, the redness remained constant in the mortadella without effects on the consumer overall acceptance.
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    Effects of sous vide vs grilling methods on lamb meat colour and lipid stability during cooking and heated display
    (Elsevier, 2020) Ortuño, Jordi; Mateo, Leticia; Rodríguez-Estrada, María; Bañón, Sancho; Tecnología de Alimentos, Nutrición y Bromatología
    The present study compared the effect of grilling (150 °C until 72 °C core temperature) and sous-vide (SV) cooking (75 °C for 35 min in a water bath under vacuum) on lamb patties immediately after cooking and after 4 h display at 65 °C. Both methods produced patties with similar (P > 0.05) weight loss, and moisture and fat contents. SV- cooking prevented (P < 0.05) the formation of thiobarbituric acid reactive substances (TBARS) and oxysterols compared to grilled patties, which showed a larger proportion of highly peroxidisable polyunsaturated fatty acids. Heated display induced dehydration, surface darkening and a reduction in the hexanal/3-methylbutanal ratio, suggesting the progression of Maillard reactions. Moreover, TBARS and some lipid oxidation-derived volatiles increased (P < 0.001), while cooked-meat aroma compounds were reduced (P < 0.001). SV-cooking inhibited (P < 0.05) the formation of malondialdehyde, and 7α- and 7β-hydroxycholesterol, and lowered the cholesterol oxidation ratio during heated display. Overall, SV-cooking may be considered way of cooking when lamb meat is to be kept warm for considerable periods before consumption.
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    Evaluation of Nannochloropsis gaditana raw and hydrolysed biomass at low inclusion level as dietary functional additive for gilthead seabream (Sparus aurata) juveniles
    (Elsevier, 2022-04-28) Sáez, María Isabel; Galafat, Alba; Vizcaíno, Antonio Jesús; Chaves-Pozo, Elena; Arizcun, Marta; Alarcón, Francisco Javier; Suárez, María Dolores; Martínez, Tomás Francisco; Ayala Florenciano, María Dolores; Anatomía y Anatomía Patológica Comparadas
    Abundant research is being carried out in the last years aimed at exploring microalgal biomass as nutrient source for different species of aquacultured fish. Some microalgae species, such as Nannochloropsis gaditana, have thick cell walls rich in cellulose, which might well reduce the bioavailability of intracellular active compounds. Among the alternatives aimed at overcoming this limitation, cellulase enzyme hydrolysis is proposed as a convenient and practical solution. In this regard, an in vitro assay was carried out, in which N. gaditana biomass was treated with cellulase (5% w/w basis) and the release of soluble compounds (reducing sugars, free amino acids and total phenolics) into the reaction medium was measured and compared to untreated raw biomass. The results confirmed increased yields of those compounds as a result of the enzyme pre-treatment. A 90-d feeding trial was also carried out in order to assess in vivo the influence of the inclusion of N. gaditana in feeds on juvenile gilthead seabream (Sparus aurata) growth, digestive physiology and body composition. Microalgal biomass was added at two inclusion levels (25 and 50 g kg 1 dry weight) in four experimental feeds, either crude or enzymatically pretreated. Animals (15.1 g initial body weight) were randomly assigned to five dietary treatments (two inclusion levels, 2.5 and 5%, and two microalgae formats, raw and enzymatically hydrolysed, plus a microalgae-free control), and distributed triplicate tanks per dietary treatment. Fish were withdrawn after 45 and 90 days, and proximate composition, muscle fatty acid and amino acid profiles, muscle and liver lipid oxidation, instrumental skin colour, digestive enzyme activities, as well as structural and ultrastructural changes in the intestinal mucosa were determined. No differences attributable to the dietary treatments were found with regard to fish growth or proximate composition at the end of the feeding trial. On the contrary, the inclusion of microalgal biomass, irrespectively of the cellulase pre-treatment, caused beneficial effects on some physiological parameters (namely digestive mucosa structure and functionality, oxidative status of muscle lipids, and instrumental colour). The only clear improvement found in fish attributable to the cellulase pre-treatment of the microalgal biomass was related to the prevention of muscle lipid oxidation. Overall, the results suggest that N. gaditana used as additive (at inclusion level below 5%) in feeds might represent a valuable nutritional strategy for S. aurata juveniles, even if growth was not affected.