Content of nitrate and nitrite in commercial and self-made beetroot juices and the effect of storage temperature

Popularity of beetroot juice (BJ) is growing due to its high inorganic nitrate content NO 3 - and its potential physiological benefits. However, the content of NO 3 - is not indicated in most commercial BJs and it can be affected by seasonal changes and storage conditions. This study analyzed the content of NO 3 - and nitrite NO 2 - in five and two commercial and self-made BJs, respectively, that were purchased in the summer and winter periods. The effect of storage temperature (20°C, 4°C, and -20°C) and pH was also analyzed. In nonconcentrated BJs, the NO 3 - content was 34 ± 20% (p = .075) in the winter than in the summer. NO 3 - was fully degraded in self-made BJ after 3 days at 20°C. This effect was attenuated by 78% and 82% when it was kept at 4°C and -20°C, respectively. The addition of lemon juice (5%) to self-made BJ was another useful approach to avoid NO 3 - degradation for 3 days when it was kept at 20°C. Regarding NO 2 - , self-made BJ had higher concentration (0.097 ± 0.01 mg/mL) compared to commercial BJs (<0.1 mg/mL; p = .001). The pH of self-made BJ was higher (6.3 ± 0.1) compared to commercial BJs (4.5 ± 0.3; p = .001). These results suggest that the content of NO 3 - in nonconcentrated BJs can substantially differ across the year and this is an important factor to take into account when recommending BJs to promote some of its potential physiological benefits.

Spray-Drying Microencapsulation of Bioactive Compounds from Lemon Verbena Green Extract

Lippia citriodora has been demonstrated to have a wide variety of phytochemicals which provide benefits to human health acting as antioxidants or anti-obesogenics. In this study, these phytochemicals were recovered using a microwave-assisted technology and applying optimal conditions and microencapsulated using spray drying. In this study, two different carbohydrates, maltodextrin (MD) and inulin (IN), were compared as carriers in the encapsulation procedure. The spray drying process was optimized by using a response surface methodology (RSM) based on a central composite design 2², where air inlet temperature and the sample:encapsulating agent ratio (S:EA) were selected as independent variables. Both designs were analyzed equally to evaluate differences between each carrying agent on polar compounds’ encapsulation (process yield (Y%), encapsulation efficiency (EE%) and recovery of compounds (R%)) during the spray drying. The EE% and R% of each polar compound was monitored by High Performance Liquid Chromatography coupled to Time-of-Flight mass spectrometer by electrospray interface (HPLC-ESI-TOF-MS). The results showed that the use of IN as a carrier increased the powder recovered and the recovery of polar compounds after the spray dry process, whereas MD achieved a higher encapsulation efficiency.

The use of beetroot extract and extract powder in sausages as natural food colorant

Four colorants (control, carmine, beetroot extract and beetroot extract powder) and two methods (fermentation and heat treatment) were used in the production of sausages. The betalain content, total phenolic substance content and ORAC and TEAC values of concentrated beetroot extract were 562.08 mg/L, 27.72 mg GAE/mL, 33.96 µmol TE/mL and 35.70 mmol TE/L, respectively. The moisture content, pH value, lightness (L*), yellowness (b*) and odor values of heat-processed sausages were higher than those of fermented sausages. 2-thiobarbituric acid reactive substances (TBARS) values were lower in sausages with beetroot extract (20.51 μmol·MDA/kg) and powder (19.03 μmol MDA/kg) than for control and carmine treatments. The use of beetroot extract and powder positively affected the sensory appearance, color, flavor and overall acceptance of sausages. Thus, beetroot extract and powder could be used as alternatives to carmine in sausage production.

Chemical, sensory, and functional properties of whey-based popsicles manufactured with watermelon juice concentrated at different temperatures

The effects of the concentration of watermelon juice at different temperatures (45, 55, or 65 °C) on the physicochemical and sensory characteristics, antioxidant capacity, and volatile organic compounds (VOCs) of whey-based popsicles were investigated. Total phenolic content, lycopene, citrulline, VOCs, melting rate, instrumental colour, antioxidant capacity, and the sensory characteristics (hedonic test and free listing) were determined. The temperature led to a significant decrease in bioactive compounds (total phenolics, lycopene, and citrulline). The popsicle manufactured with reconstituted watermelon juice concentrated to 60 °Brix at 65 °C presented higher antioxidant capacity and was characterized by the presence of alcohols, aldehydes and ketones and presented a similar acceptance to the untreated popsicle (except for flavour). It is possible to combine whey and concentrated watermelon juice for the manufacture of bioactive-rich popsicles, using the concentration temperature of 65 °C as a suitable processing condition for potential industrial applications.