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Abstract: Functional milk beverages (FMB100 and FMB200) fortified with phenolic compounds (100 and 200mg/l) extracted from olive vegetable water, and fermented with γ-amino butyric acid (GABA)-producing (Lactobacillus plantarum C48) and autochthonous human gastro-intestinal (Lactobacillus paracasei 15N) lactic acid bacteria were manufactured. A milk beverage (MB), without addition of phenolic compounds, was used as the control. Except for a longer latency phase of FMB200, the three beverages showed an almost similar kinetic of acidification, consumption of lactose and synthesis of lactic acid. Apart from the beverage, Lb. plantarum C48 showed a decrease of ca. Log 2.52–2.24cfu/ml during storage. The cell density of functional Lb. paracasei 15N remained always above the value of Log 8.0cfu/ml. During fermentation, the total concentration of free amino acids markedly increased without significant (P >0.05) differences between beverages. The concentration of GABA increased during fermentation and further storage (63.0±0.6–67.0±2.1mg/l) without significant (P >0.05) differences between beverages. After fermentation, FMB100 and FMB200 showed the same phenolic composition of the phenol extract from olive vegetable water but a different ratio between 3,4-DHPEA and 3,4-DHPEA-EDA. During storage, the concentrations of 3,4-DHPEA-EDA, p-HPEA and verbascoside of both FMB100 and FMB200 decreased. Only the concentration of 3,4-DHPEA increased. As shown by SPME-GC-MS analysis, diactetyl, acetoin and, especially, acetaldehyde were the main volatile compounds found. The concentration of phenolic compounds does not interfere with the volatile composition. Sensory analyses based on triangle and paired comparison tests showed that phenolic compounds at the concentrations of 100 or 200mg/l were suitable for addition to functional milk beverages. [Copyright &y& Elsevier]

Abstract: Over 40days, lambs were fed: concentrate (C), concentrate containing 20% linseed (L), concentrate containing 35% olive cake (OC), or concentrate containing 10% linseed and 17% olive cake (OCL). The polyunsaturated fatty acids (PUFA) and peroxidation index (PI) in phospholipids were increased by the L and OCL treatments (P =0.007 and P =0.003, respectively). The OC and OCL diets increased the concentration of tocopherol in muscle (P <0.001). Compared to the OC and OCL diet, the L diet increased fatty acid oxidation, measured as conjugated dienes (CD; P =0.003), peroxides (PV; P <0.001) and TBARS (P =0.002) in minced muscle over 11days of storage in high-oxygen atmosphere. Also, the L diet increased (P <0.001) the levels cholesterol oxidation products (COPs). In conclusion, feeding olive cake improved the oxidative stability of lamb meat and the combination of olive cake and linseed improved the fatty acid composition of meat without compromising its oxidative stability. [Copyright &y& Elsevier]

Abstract Phenols from olive mill waste water (OMWW) represent valuable functional ingredients. The negative impact on sensory quality limits their use in functional food formulations. Chemical interactions phenols/biopolymers and their consequences on bioactivity in plant-base foods have been widely investigated, but no studies to date have explored the variation of bitterness, astringency and pungency induced by OMWW phenols as a function of the food composition. The aim of the paper was to profile the sensory and chemical properties of phenols from OMWW in plant-base foods varied in their macro-composition. Four phenol concentrations were selected (0.44, 1.00, 2.25, 5.06 g/kg) to induce significant variations of bitterness, sourness, astringency and pungency in three plant-base food: proteins/neutral pH – bean purée (BP), starch/neutral pH – potato purée (PP), fiber/low pH – tomato juice (TJ). The macro-composition affected the amount of the phenols recovered from functionalized food. The highest recovery was from TJ and the lowest from BP. Two groups of 29 and 27 subjects, trained to general Labelled Magnitude Scale and target sensations, participated in the evaluation of psychophysical curves of OMWW phenols and of functionalized plant-base foods, respectively. Target sensations were affected by the food macro-composition. Bitterness increased with phenol concentration in all foods. Astringency and sourness slightly increased with concentration, reaching the weak-moderate intensity at the highest phenol concentration in PP and TJ only. Pungency was suppressed in BP and perceived at weak-moderate intensity in PP and TJ sample at the highest phenol concentration. Proteins/neutral pH plant-food (BP) resulted more appropriate to counteract the impact of added phenol on negative sensory properties thus allowing to optimize the balance between health and sensory properties. Graphical abstract Unlabelled Image Highlights • Food macro-composition affects the amount of recovered phenols. • The lowest recovery was from proteins/neutral pH plant-food. • Intensities of sensations depend by phenol concentration and food macro-composition. • Proteins/neutral pH food counteracted phenol induced "warning" sensations. [ABSTRACT FROM AUTHOR]

In recent years, the temperature of processed olives in many olive-growing areas was often close to 30 °C, due to the global warming and an early harvesting period. Consequently, the new trends in the extraction process have to include the opportunity to cool the olives or olive paste before processing to obtain high quality EVOO. A tubular thermal exchanger was used for a rapid cooling treatment (CT) of olive paste after crushing. The results did not show a significant difference in the oil yield or any modifications in the legal parameters. The cooling process determined a significant improvement of phenolic compounds in all the three Italian cultivar EVOOs analyzed, whereas the volatile compounds showed a variability largely affected by the genetic origin of the olives with C 6 aldehydes that seem to be more stable than C 6 alcohols and esters. [ABSTRACT FROM AUTHOR]

The potential of a phenolic extract (PE) from olive vegetation water (OVW) to limit the negative effects of frying was tested after adding it at different concentrations to a refined olive oil (RO). Its efficacy was also compared to ROs containing butylated hydroxytoluene (BHT) and an extra virgin olive oil (EVOO) with a high polyphenol content. Analyses of the oils collected after 30 min, 1, 2, 4, 6, 8, 10 and 12 h of frying at 180 °C, demonstrated that degradation of the polyphenols was proportional to the original content; at a concentration of at least 400 mg/kg of polyphenols, PE was able to reduce oxidation of the tocopherols and the emission of low-molecular-weight aldehydes better than BHT and with similar results to the EVOO. In addition, secoiridoid oxidative compounds were examined by high-performance liquid chromatography/triple quadrupole tandem mass spectrometry with electrospray ionisation. [ABSTRACT FROM AUTHOR]

Abstract: The aim was to investigate the effects of three types (A, B and C) of stoned and dehydrated olive pomaces (OPs), differing in olive cultivar, on productive performance and meat quality of growing rabbits. The inclusion of OPs (5%) negatively affected the performance of rabbits as it reduced the feed intake, growth rate, carcass weight and dressing out percentage (P<0.05). Compared with the control, the meat of OP rabbits had a greater amount of monounsaturated and a lower amount of polyunsaturated fatty acids (P<0.05), independent of the type of OP used. Oxidative processes in the meat of OPA and OPB were higher (P<0.05), whereas OPC showed the same levels as the control group. This was due to the higher total polyphenol concentration and to the concomitant lower peroxide value of OPC. These results recommend the use of OP in rabbit diet with caution, taking into account the quality of the by-product in terms of oxidative status. [Copyright &y& Elsevier]