דו״ח מאומת

The current study investigates the feasibility of preparing Arabic bread from wheat flour, sweet potato flour, or peeled sweet potatoes based on the nutritional values, technological characteristics, and sensory properties of the final products. First, we analyzed the proximate, elemental, total and individual phytochemical compositions of the raw materials and bread samples. The analysis showed that potassium, calcium, and phosphorus were higher in peels than pulp, in the same manner to the total phenolics, flavonoids, and anti-radical scavenging activities. Phenolic acids and flavonols were quantified, where…

PMID: 37107453

Orange-fleshed sweet potato (OFSP) is a rich source of carotenoids, phenolics, flavonoids, and starch that are influenced by thermal processing. This study compared the effects of steaming (15-45 min) and air-frying (5-15 min) on the color, bioactive composition, starch content, and antioxidant properties of OFSP peel and flesh to assess processing-induced changes. Unprocessed samples served as the baseline for evaluating percentage and fold changes. Results revealed tissue-specific responses. Steaming preserved flesh brightness (L*, 79) and moderately enhanced carotenoids (0.68 µg/g), anthocyanins (up to 40.5 µg/g in peel), phenolics (2.19-2.27 mg GAE/g), and flavonoids (up to 3.32 mg QE/g). Air-frying induced more pronounced increases in peel bioactives, with carotenoids (4.79 µg/g, 14-fold), phenolics (6.86 mg GAE/g, more than 3-fold), flavonoids (11.75 mg QE/g, more than 20-fold), and transient anthocyanin elevation (61.62 µg/g at 5 min), but prolonged exposure caused degradation in flesh. Starch remained stable in the peel but decreased in the flesh. Antioxidant activity showed similar tissue- and treatment-specific patterns. Steaming preserved structural integrity and bioactive stability, whereas short-duration air-frying maximized peel carotenoids and phenolics. These findings provide insights for optimizing thermal processing to enhance nutritional quality and functional properties in OFSP.…

PMID: 41227611

Sweet potato (Ipomoea batatas) is a globally important autohexaploid root and tuber crop. Fusarium root rot threatens its entire growth, harvest, and storage period, thereby reducing yield and quality. Therefore, a deeper understanding of Fusarium pathogenicity and sweet potato defense is urgently required. Here, two single nucleotide polymorphisms are identified within the promoter region of the I. batatas CHY zinc-finger and ring protein1 (IbCHYR1) gene that encode an E3 ubiquitin ligase linked to root rot resistance. In susceptible varieties, the high dosage allele Pro::IbCHYR1^Hap1 leads to increased expression of IbCHYR1. Overexpression of IbCHYR1 increases susceptibility to root rot and Fusarium wilt. IbCHYR1 interacts with the I. batatas CCCH-type zinc-finger protein (IbZnFR) to promote its degradation. IbZnFR confers resistance to root rot and Fusarium wilt and improves yield by more than 10%. The high dosage Pro::IbZnFR^Hap2 allele is associated with resistance to root rot disease. Moreover, FfRlpA2, a conserved Fusarium effector, is identified as a protease inhibitor that stabilizes and hijacks IbCHYR1 to degrade IbZnFR, thereby inhibiting multiple defense pathways. These findings provide insights into Fusarium pathogenicity and a genetic basis for root rot research and improvement of disease-resistant sweet potato varieties.…

PMID: 40569265

Street-vended foods are preferred for their convenience and affordability, yet unsanitary handling practices can raise the risk of microbial contamination. This study aimed to assess the microbiological quality of some selected street foods, vendor's safety practices, knowledge, and attitudes in Dessie Town, Ethiopia. A cross-sectional study involving 170 street food vendors that employed a structured questionnaire and observational checklist as data collection tools. A total of 75 food samples were collected from various locations in the town using sterile stomacher bags. The samples comprised 15 portions each of "Chips", "Sambusa", "Bonbolino", "Ambasha", and "Sweet potatoes". Every food sample was subjected to homogenization, serial dilution, and spread plating to detect microorganisms using standard microbiological techniques. The data was analyzed using SPSS software, version 20.00. The study revealed a predominance of female vendors (88.8%), and vendors lack awareness about spoiled food characteristics (94.1%). Surprisingly, a significant portion of vendors did not use gowns (68.8%) or gloves (82.4%) while vending. Most vendors 60.0% did not cover cooked food, and 58.8% of vending sites had dust or filth nearby. Regarding microbial quality, "Sambusa" had the highest mean count (1.23 × 10^- 3 CFU/g) of aerobic mesophilic bacteria. "Bonbolino" and "Sweet Potato" showed Staphylococci counts of 2.61 × 10^- 2 CFU/g and 2.64 × 10^- 2 CFU/g, respectively. "Sweet potatoes" had the highest coliform count (2.4 × 10^- 2 CFU/g), while "Ambasha" exhibited the highest Salmonella count (3 × 10^- 2 CFU/g). Vis-a-vis the study points, the finding indicated that the bus station had the highest aerobic mesophilic bacteria count (1.12 × 10^- 3 CFU/g), while Kelem meda, Piasa, and Segno gebeya recorded the highest Staphylococcus counts. Regarding the antibacterial susceptibility profiles, Salmonella has shown susceptibility to most antibiotics tested, such as Amoxicillin and Cefradine, but has been found resistant to Oxacillin. Conversely, E. coli has exhibited resistance to all antibiotics except for Gentamicin. Given the concerns observed in microbiological quality and safety issues of street vended foods in Dessie Town, it is crucial to introduce inclusive training programs for vendors.…

PMID: 41125724

This study evaluated the effectiveness of washing potatoes inoculated with Escherichia coli, Listeria monocytogenes, and murine norovirus (MNV) through agitation with peroxyacetic acid (PAA) and chlorine dioxide. Potential cross-contamination during simultaneous washing of inoculated and uninoculated potatoes and the effect of water reuse were also assessed. E. coli showed a reduction of 1.86-2.51 log colony-forming units (CFU)/potato when treated with 40 ppm PAA and 1.98-2.97 log CFU/potato when treated with 80 ppm chlorine dioxide (ClO₂), both for 1-5 min. L. monocytogenes showed a reduction of 2.59 log CFU/potato when treated with 120 ppm PAA for 1 min and 2.55 log CFU/potato when treated with 80 ppm ClO₂ for 5 min. MNV showed a reduction of 2.28 log CFU/potato when treated with ≥40 ppm PAA for 5 min; however, no significant reduction was noted on treatment with ClO₂. During tap water washing, cross-contamination with E. coli and L. monocytogenes occurred at 3.01 and 3.22 log CFU/potato, respectively; however, MNV was not detected because of its higher LOD. PAA completely inhibited E. coli transfer (below the LOD), whereas ClO₂ allowed limited transfer (0.83-1.30 log CFU/potato). However, L. monocytogenes transfer persisted in both treatments (2.74-3.46 log CFU/potato), showing only partial mitigation compared to tap water washing. Reuse of wash water significantly increased cross-contamination with E. coli and L. monocytogenes (p < 0.05); however, MNV transfer was not observed under any condition. For eradicating other types of microorganisms, the concentration must be determined according to the characteristics of each microorganism. PRACTICAL APPLICATIONS: This study revealed that washing potatoes with disinfectants like PAA or ClO₂ can reduce harmful bacteria and viruses. PAA was effective even at concentrations below the regulatory limits. Hence, it may help prevent cross-contamination during bulk washing processes in food production facilities and kitchen environments.…

PMID: 41164906