Tomato Waste as a Source of Biologically Active Compounds

Large amounts of wastes are generated annually by the vegetable processing industry, their efficient management and valorization representing a priority research area. Recent research suggested the possibility of reusing tomato pomace as a cheap source of many bioactive compounds, such as antioxidants, soluble dietary fibers and vitamins. The high initial moisture of fresh tomato pomace and the presence of considerable levels of nutrients make this waste susceptible to microbial degradation. Therefore, the fresh pomace of three tomato varieties were preserved by two different methods and then analyzed regarding the total phenolics content, flavonoids, lycopene and antioxidant activity. The results showed that all samples contained considerable amounts of phenolic compounds and exhibit good antioxidant properties. A higher lycopene content was obtained for dehydrated samples, other similar studies explaining that heat processing can breakdown the cellular walls and the chromoplast membranes, leading to a better release. The obtained results highlight the potential of reusing tomato processing waste as source of bioactive compounds and encourages the implementation of a sustainable valorization plan

Inhibitory Effects of Iso-α and β Hop Acids Against Pediococcus pentosaceus

The goal of the research was to assess the inhibitory effects of  hop extracts, iso-α and β acids, against Pediococcus pentosaceus bacteria, during a short incubation period, both in liquid selective media (high pH values) and beer wort fermentation (low pH values) and testing if the identified iso-α acid stress changes the activity of S. cerevisiae boulardii yeast and ethanol production. Flow cytometry analysis was used for bacterial and yeast cell viability. In relation to the antibacterial activity of β-acids, a lower viability of Pediococcus pentosaceus cells was observed after a short incubation period in selective media, under iso-α acid stress. In beer wort, for a mixed culture with P. pentosaceus bacteria and S. cerevisiae boulardii yeast, under iso-α acid stress conditions at pH 4.0-5.0, Pediococcus pentosaceus exhibited lower cell viability (20.7%) than in selective media (61.4%). Regarding iso-α hop acid on S. cerevisiae boulardii yeast, the results showed that iso-α does not change the S. cerevisiae activity but prevents the culture from being contaminated by Pediococcus pentosaceus. The results highlighted reliable inhibitory effects of iso-α and β-acids against P. pentosaceus, both at pH 6.0-7.0 and pH 4.0-5.0, which open the possibility of hops being used as a supplement to prevent beverage contamination with spoilage microorganisms

Reintegration of Brewers Spent Grains in the Food Chain: Nutritional, Functional and Sensorial Aspects

[EN] Nowadays, the pandemic situation has encouraged the idea of sustainable healthy foods leading to new trends in food consumption. Brewers spent grain (BSG) represents a potential functional food rich in fiber, protein, lipids, mineral and phenols that needs to be further exploited. In this vein, five different BSG types were collected from local breweries and valorized in cookies manufacturing. Thus, proximate composition (protein, minerals, lipids, ash, crude fiber and carbohydrates) was analyzed using AACC (American Association of Cereal Chemists) methods, DPPH (2,2-Diphenyl-1-picrylhydrazyl), and Folin Ciocalteu methods were used to determined antioxidant activity and total phenols, while minerals and aroma volatile compounds were performed using inductively coupled plasma optical emission spectrometry (ICP-OES) and ITEX/GC-MS (in tube extraction gas chromatography-mass spectrometry) respectively. Color and physical characteristics, together with sensorial analysis, were also evaluated. The results highlighted a significant difference between BSG samples, mainly from the total phenols, antioxidant activity and aroma volatile compounds point of view. BSG volatiles compounds from the aldehydes group such as 2-methyl-propanal, 3-methyl-butanal and 2-methyl-butanal were identified also in the final baked goods, leading to a pleasant and appreciated consumers' taste and aroma. Furthermore, cookies sensorial analysis emphasized that the sample manufactured with BSG from light and dark malt mixture was more appreciated by consumers, attaining the highest hedonic scores.This research was supported by a grant of the Romanian Ministry of Education and Research, CCCDI-UEFISCDI, project number PN-III-P2-2.1-PED-2019-3622, within PNCDI III.Farcas, AC.; Socaci, SA.; Chis, MS.; Pop, OL.; Fogarasi, M.; Paucean, A.; Igual Ramo, M.... (2021). Reintegration of Brewers Spent Grains in the Food Chain: Nutritional, Functional and Sensorial Aspects. Plants. 10(11):1-21. https://doi.org/10.3390/plants10112504121101

Aloe vera gel microcapsules and essential oils of thyme and oregano incorporated in spreadable goat cheese: impact on its microbiological, physicochemical, and sensory characteristics during storage

The aim of this study was to develop a new assortment of high-quality cream cheese, with a high amount of biologically active compounds, namely a spreadable cheese from goat milk with addition of Aloe vera microcapsules and essential oils of thyme and oregano. The research was focused on the testing and optimization of an appropriate manufacturing recipe for this new product. Two assortments were made: one with Aloe vera microcapsules and thyme essential oil and the other one with Aloe vera microcapsules and oregano essential oil. For each assortment two different concentrations of Aloe vera and essential oils were tested. The obtained products were analysed for organoleptic, physico-chemical (fat, protein, total dry matter, sodium chloride and acidity) and microbiological parameters. In terms of consumer preferences, the cream cheese with 3% microcapsules of Aloe vera gel and 0.018% thyme essential oil was the most appreciated in terms of commercial aspect, consistency, and taste. We concluded that the addition of Aloe vera microcapsules improves the sensory characteristics and leads to an increase nutritional value of the finished product. Also, the addition of essential oils (thyme and oregano) ensured a stable quality during storage