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Sorghum and pearl millet are grain crops that can grow in semi-arid climates, with nutritional and bioactive properties superior to those of major cereals such as rice, wheat, and maize. However, these properties vary a lot, depending on the genetic factors, growing conditions, and place of cultivation. Four sorghum and two pearl millet grains cultivars grown in the Far-North region of Cameroon were screened for their chemical composition and antioxidant profile. The proximate and mineral analyses were performed using AOAC standard methods. The antioxidant profile was assayed spectrophotometrically and details on the phenolic compounds were investigated using HPLC. The pearl millet cultivars, especially mouri, showed higher contents of proteins, lipids, ash, calcium, copper, iron, and zinc. The red sorghum specifically exhibited the greatest amounts of total polyphenols (82.22 mg GAE/g DE), total flavonoids (23.82 mg CE/g DE), and total 3-deoxyanthocyanidin (9.06 mg/g DE). The most abundant phenolic compound was gallic acid, while the most frequent were chlorogenic and ferulic acids. The maximum antioxidant activity against DPPH was observed in yellow-pale sorghum (87.71%), followed by red sorghum (81.15%). Among the studied varieties of cereals, mouri pearl millet and red sorghum were the best sources of nutrients and bioactive compounds, respectively. Their consumption should be encouraged to tackle nutrient deficiencies and non-communicable diseases within local populations. [ABSTRACT FROM AUTHOR]

A study on Cameroonian edible and medicinal plants was undertaken to assess their potential as food preservatives and natural food colorants. The ultrasound-assisted technique was used for the extraction of bioactive compounds. A total of 16 extracts prepared from 7 plants (Aframomum melegueta S., Ageratum conyzoides L., Cympobogon citratus Stapf, Garcinia kola Heckel, Lantana camara L., Nauclea diderrichii, Vernonia amygdalina) were assayed to detect phytochemicals and assess antioxidant potential using the scavenging DPPH radical method and antimicrobial activity (10 mg/mL) against ten microorganisms by the agar well diffusion method. The ethanolic extract from L. camara leaves revealed the highest polyphenols and flavonoids contents. In contrast, the hexane/acetone extract from A. conyzoides and L. camara leaves had the highest chlorophyll a (Chl a) and chlorophyll b (Chl b) contents, whereas the highest carotenoid content was found in L. camara leaves. The ethanol extracts exhibited more significant antioxidant activity than hexane/acetone extracts. All seven plants (100%) inhibited the growth of at least one tested foodborne and spoilage bacteria and fungi. The germination of both Bacillus spp. spores were also affected. The hexane/acetone extracts were by far the best antimicrobial agent, and extract from L. camara leaves was one of the most effective, with a large antimicrobial spectrum. The antimicrobial activity of extracts was correlated to the amount of carotenoids and chlorophylls. HPLC-DAD revealed bioactive compounds as chlorogenic and caffeic acids found as major phenols in ethanolic extract of L. camara leaves, whereas lutein, carotene, and zeaxanthin were the specific carotenoids present in hexane/acetone extract of the same plant. [ABSTRACT FROM AUTHOR]

Thermal and/ or high pressure inactivation of polyphenol oxidase, isolated from grapes is studied as a function of pH. Pressure and temperature are found to act synergistically except in the high temperature low pressure region where an antagonistic effect is observed.

Acrylamide as a known processing contaminant was determined in various heat-treated plum products purchased from a local market using LC/ESI-MS-MS. The highest level of acrylamide in the range up to 60 μg/kg was detected in a plum stew known as a “povidla“, and in prunes, respectively. These products typically undergo intensive heat treatment that may take from several hours to days. Using a fruit dehydrator in home production of prunes, a low level of acrylamide under LOQ (15 μg/kg) was detected in comparison to most commercial products. Only in one of the prune samples from the market was the acrylamide content near to LOQ. The highest content of acrylamide (46 μg/kg) was detected in the Slovak sample of prune originated in Nitra region. High acrylamide content, in the range from 23 to 45 μg/kg, was observed in prunes from South America. In the rest of analysed heat-treated plum products such as plum juice, plum compote or baby food with plum puree, acrylamide was not detected due to moderate conditions during thermal processing: temperature below 120 °C and a shorter time of thermal exposure. The total phenolic content and antioxidant capacity of prunes were analysed using a UV-VIS-NIR spectrophotometer and an electron paramagnetic resonance (EPR) spectroscopy. Homeprepared prunes were characterized by the highest content of phenolics (4780 mg GAE/kg) and antioxidant capacity (14.6 mmol TEAC/kg). Commercial samples of prunes reached phenolics in the range from 1619 to 3461 mg GAE /kg, and antioxidant capacity was observed between 6.1 and 12.1 mmol TEAC/kg. Antioxidant capacity of prunes strongly correlated with total phenolic content and yellow and red colours measured in a CIELab system. However, no significant correlation between the acrylamide and antioxidative or organoleptic properties of prunes was observed. Moreover, it was noticed that bio production of plums did not demonstrate any positive impact on final acrylamide content or antioxidant capacity in comparison to conventional technology. [ABSTRACT FROM AUTHOR]

Susceptibility to enzymes hydrolysis is used as an index of flexibility since partial unfolding of protein molecules generally results in increased hydrolysis rate. Two set of experiments were performed on the effect of thermal treatment in the temperature range of 60-85°C on the susceptibility of whey protein concentrate to enzymatic hydrolysis by Proteinase K at 37°C and pH 7.5 and 8.0. Heat treatment in a certain time-temperature combination results in a significant increase in degree of hydrolysis, as monitored by OPA-NAC technique. The time-dependent changes in the degree of hydrolysis were described by a fractional conversion model, which enables calculations of activation energy. Whey proteins concentrate seems to be heat-sensitive for enzymatic hydrolysis, confirming that during heat treatment at neutral/alkaline pH the substrate is changing, since the dimmer dissociates with the exposure of hydrophobic residues. [ABSTRACT FROM AUTHOR]

Consumers, regulators, and the food industry increasingly require that foods comply not only with the label descriptions of food content, but also with information regarding the food origin. For example, the wine industry has a long history of labelling wines based on varietal, regional, or age (vintage) - related properties. However, regulatory agencies are now beginning to require methods to confirm this label information. Wine retailers are also facing voluntary or mandatory labelling requirements that will indicate regional or country-of-origin, species and/or varietal information. As a result, development of reliable analytical methods to confirm the authenticity of the label information is needed. The adulteration of wine is usually accomplished by addition of alcohol, water, dyes and aromas to wine of minor commercial value. As these wines are usually produced with inadequate conditions of hygiene, they become of high risk for the human health. Another risk for the consumer of adulterated wines is the ingestion of products elaborated of raw materials not under control evidence. The aim of this study was to identify the adulterated wines obtained in vineyards of Vrancea County by the private and local producers during the time period of 2006-2008. From the 913 wine samples analysed it was noticed that the cheap wines are frequently adulterated. The trend of wine adulterations from Vrancea County had a decreasing value from 2006 (70.3%) to 2008 (35.1%). The decreasing of the adulterated wines from 2006 to 2008 is probably due to the application of Romanian legislative regulations on wine quality level. [ABSTRACT FROM AUTHOR]

In commercial ethanol production producers often use sugar cane molasses as raw material due to their abundance and low costs. The most employed microorganisms used for fermentation is Saccharomyces cerevisiae yeasts due to their ability to hydrolyze sucrose from cane molasses into glucose and fructose, two easily assimilable hexoses. The aim of this study was to evaluate the application of different strains of Saccharomyces cerevisiae for sugar cane molasses in order to produce bioethanol. According to the obtained results the strain D1 (Safdistil C-70) achieved higher values of the specific growth rate in comparison with other strains used. The maximum ethanol productivity of 2.33 g/L.h was achieved around 36 hours of fermentation by using the yeast D1. Therefore, the optimal duration of the fermentation process in technical and economic terms should be considered. [ABSTRACT FROM AUTHOR]

The aim of this study was to follow up the evolution of both the physico-chemical indices and the dynamics of the oxidative enzymes during the maturation of white grapes, more particularly until the grapes reach technological maturity. Studying the dynamics of the physico-chemical indices during the maturation of the grapes an increase of the content of glucides, polyphenols, antiocyanins, simultaneously with the decrease of the acidity was noticed. The enzymatic activity of tyrosinase is high at the moment when the grapes are in the beginning of the ripening period and afterwards it presents a decline during the ripening of the grapes, having a relatively low level before harvesting. The enzymatic activity of the laccase increases up till the full maturity of the grapes, then it decreses a little before the harvesting of the fruit, having lower values than at the start of ripening. The enzymatic activity of the peroxidase increases up till the full maturity of the grapes, then it decreses a little before the harvesting of the fruit, having lower values than when it begins to ripen. [ABSTRACT FROM AUTHOR]

The growing interest of consumers in healthy organic products has increased the attention to the organic production of beetroot. In this regard, six field experiments were conducted in 2017 and 2018 in three different locations under the specific conditions of organic agriculture, and fifteen beetroot genotypes, including one F1 hybrid as a commercial control and one breeding line, were compared regarding the content of the total dry matter, total soluble sugar, nitrate, betalain, and total phenolic compounds in order to investigate the genetic potential of new and existing open-pollinated genotypes of beetroot regarding the content of their bioactive compounds. The results of this study indicated a significant impact of genotype (p < 0.05) on all measured compounds. Furthermore, results revealed a significant influence of the interactions of location × year (p < 0.05) on the beetroot composition, and, thus, the role of environmental conditions for the formation of tested compounds. The total dry matter content (TDMC) of beetroots varied between 14.12% and 17.50%. The genotype 'Nochowski', which possessed the highest total soluble sugar content with 14.67 °Bx (Brix), was among the genotypes with the lowest nitrate content. On the contrary, the cylindrical-shaped genotype 'Carillon RZ' (Rijk Zwaan), indicated the lowest sugar content and the highest nitrate concentration. The amount of total phenolic compounds ranged between 352.46 ± 28.24 mg GAE 100 g−1 DW (milligrams of gallic acid equivalents per 100 g of dry weight) and 489.06 ± 28.24 mg GAE 100 g−1 DW for the red-colored genotypes which is correlated with the high antioxidant capacity of the investigated genotypes. Due to the specifics of the required content of bioactive compounds for various products, the selection of suitable genotypes should be aligned with the intended final utilization. [ABSTRACT FROM AUTHOR]