Pterospartum tridentatum Liqueur Using Spirits Aged with Almond Shells: Chemical Characterization and Phenolic Profile.

With great cultural significance, spirits and distillate beverages constitute an important niche market in Europe. The development of new food products, particularly for the functionalization of these beverages, is increasing exponentially. The present work aimed to develop a new wine spirit beverage aged with almond shells and flowers of P. tridentatum for further characterization of bioactive and phenolic compounds, coupled with a sensorial study to evaluate the acceptance of this new product by the market. Twenty-one phenolic compounds were identified, mainly isoflavonoids and O- and C-glycosylated flavonoids, especially in P. tridentatum flowers, indicating that it is a highly aromatizing agent. The developed liqueur and wine spirits (almonds and flowers) showed distinct physicochemical properties, with the last two samples showing greater appreciation and purchase intention by consumers due to their sweetness and smoothness. The most promising results were found for the carqueja flower, which should be further investigated in an industrial context to contribute to its valorization in its regions of origin, such as Beira Interior and Trás-os-Montes (Portugal).

Use of ultrafiltrated cow's whey for the production of whey cheese with Kefir or probiotics.

BACKGROUND: In Southern European countries, whey cheeses are normally produced with ovine or caprine whey. Cow's cheese whey can also be used, although the whey cheese yield is low (2-3%, w/v) which discourages its use. In the present study, bovine cheese whey was concentrated by ultrafiltration for the production of four types of whey cheeses (Requeijão): conventional, without any addition (WC); with 10% (w/w) addition of cream (WCC); with cream fermented with Kefir culture (WCCK); and with cream fermented with Bifidobacterium sp. culture (WCCBB12). RESULTS: Whey cheeses with cream presented lower protein content (330-360 g kg-1 , dry basis) and higher levels of total solids (220-250 g kg-1 ) and fat (300-330 g kg-1 , dry basis) than WC. C16:0 and C18:1 were the most abundant fatty acids present, with 31% and 38%, respectively. The small differences found concerning instrumental determination of colour and texture were not perceived by panelists. However, the presence of Kefir and probiotics decreased the elastic modulus (G') of the samples, as well as their viscosity. Fermentation with Kefir presented the highest counts of lactic acid bacteria (7 logUFC g-1 ). However, after 14 days of refrigerated storage, the counts of yeasts and moulds reached 6 logUFC g-1 in all products, indicating the need for appropriate packaging solutions. CONCLUSION: Ultrafiltration of bovine whey allows for the efficient production of bovine whey cheeses. The addition of cream fermented with Kefir or BB12 appears to be an efficient methodology to incorporate Kefir or probiotic bacteria in Requeijão, improving its nutritional and sensory characteristics, alongside the potential for the extension of its shelf-life. © 2020 Society of Chemical Industry.

Low Fat Yoghurts Produced with Different Protein Levels and Alternative Natural Sweeteners.

The food industry is looking for substitutes for sucrose in food items due to the excessive consumption of products with added sugar and the demand for healthier products. Alternative natural sweeteners can help achieve this goal. Different types of low-fat yoghurts (1% fat), with low-protein and high-protein levels (3% and 4.5-6.5% protein, respectively), were produced using alternative natural sweeteners. The low-protein yoghurts were made with stevia (0.03% w/w) or agave syrup (4.5% w/w). The high-protein yoghurts were made with stevia (0.04% w/w), xylitol (6% w/w) or honey (6% w/w). Sucrose (6% w/w) was used as a control in both trials. pH and titratable acidity, CIEL*a*b* color parameters, syneresis index, rheology and the texture profile of the low-fat yoghurts were evaluated over refrigerated storage. All products underwent sensory evaluation by an untrained panel. The high-protein yoghurts were found to be more acidic (>1% as lactic acid), had a lower syneresis index (between 2.1 and 16.2%) and a better consistency (stronger gel structure) than the low-protein yoghurts. In terms of rheological parameters, stevia-sweetened yoghurts scored higher than the other sweetened yoghurts, showing a better gel structure. The different sweeteners tested did not significantly affect the sensory properties of the yoghurts, although the high-protein yoghurts scored higher for most of the attributes evaluated. Overall, consumers preferred stevia-sweetened yoghurts to yoghurts sweetened with sucrose or agave for the low-protein yoghurts. Of the tested formulations, those containing high protein with the alternative natural sweetener xylitol received higher scores in all attributes. These results reveal the potential of the tested natural sweeteners as sucrose substitutes, while contributing to improving the nutritional value of yoghurts.

Pomegranate Peels and Seeds as a Source of Phenolic Compounds: Effect of Cultivar, By-Product, and Extraction Solvent.

The nutraceutical properties of Punica granatum L. are not restricted to the edible portion of the fruit but also to the peels and seeds, flowers, leaves, and tree bark. The recovery and valorization of the peel and seeds (ca. 50% of the whole fruit), besides the positive environmental impact, can be viewed as a source of natural bioactive compounds. Thus, the bioactive properties of extracts of pomegranate peel and seeds from Acco and Wonderful known cultivars, as well as of the novel Big Full cultivar, were evaluated. The dried and ground pomegranate by-products were submitted to a conventional solid/liquid extraction with ethanol/water mixtures (0%, 25%, 50%, and 75% of EtOH, v/v). The obtained extracts were characterized in terms of total phenolic compounds (TPC), total flavonoids (TF), and antioxidant activity (AA), determined by the DPPH radical scavenging activity and expressed as IC50 (half maximum inhibitory concentration). With the exception of the Acco cultivar, the extraction yield (EY) was higher for peels, whose extracts showed higher TPC, TF, and IC50 (lower AA). The extracts obtained from the by-products of the Big Full cultivar had a statistically higher overall bioactive potential (TPC: 0.36 mg GAE/mg extract; TF: 0.031 mg CATE/mg extract; IC50: 0.51 mg/mL) compared to the other two studied cultivars. Furthermore, the EY was enhanced by solvents richer in ethanol (50-75%), allowing obtaining extracts richer in TPC and TF with higher AA. Finally, it was shown that EY combined with bioactive data allowed a satisfactory principal component unsupervised differentiation of the pomegranate extracts according to the type of by-product used.

Whey Protein Concentrate/Isolate Biofunctional Films Modified with Melanin from Watermelon (Citrullus lanatus) Seeds.

Valorization of food industry waste and plant residues represents an attractive path towards obtaining biodegradable materials and achieving "zero waste" goals. Here, melanin was isolated from watermelon (Citrullus lanatus) seeds and used as a modifier for whey protein concentrate and isolate films (WPC and WPI) at two concentrations (0.1% and 0.5%). The modification with melanin enhanced the ultraviolet (UV) blocking, water vapor barrier, swelling, and mechanical properties of the WPC/WPI films, in addition to affecting the apparent color. The modified WPC/WPI films also exhibited high antioxidant activity, but no cytotoxicity. Overall, the effects were melanin concentration-dependent. Thus, melanin from watermelon seeds can be used as a functional modifier to develop bioactive biopolymer films with good potential to be exploited in food packaging and biomedical applications.

Growth aspects of the marine microalga Nannochloropsis gaditana.

Nannochloropsis is well appreciated in aquaculture due to its nutritional value and the ability to produce valuable chemical compounds, such as pigments (zeaxanthin, astaxanthin...) and polyunsaturated fatty acids (EPA). Commercial exploitation needs high cell densities but the low growth rate and the small size of cells are practical difficulties. To increase biomass concentration the positive effect of several factors was evident: (i) pH approximately 8 control (with dilute Tris-HCl buffer); (ii) the continuous illumination (no evidence of photo-inhibition was observed); (iii) a quite large temperature range (25+/-5 degrees C); (iv) the presence of organic carbon source (with the danger of contamination); (v) the presence of urea as an additional nitrogen source (10 mM); (vi) a small air flow rate with large bubbles can be more efficient for CO(2) mass transfer (associated to reduced shearing).