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Summary: The present study provided a new alternative for efficiently producing lipopeptides by calcium lactate and expanded potential applications of lipopeptides for ensuring food safety. The results indicated that the addition of calcium lactate significantly improved bacillomycin D production. When fed 150 mL of fermentation medium with 6.5 g/L calcium lactate at the batch fermentation time of 102 h, the maximum production of C14 bacillomycin D (C14BD), C15 bacillomycin D (C15BD), C16 bacillomycin D (C16BD), C17 bacillomycin D (C17BD) and total C14‐17 bacillomycin D (TBD) were 298.96, 345.43, 149.56, 216.6 and 1010.55 mg/L at 162 h, respectively. In addition, calcium lactate effectively induced biosynthesis of bacillomycin D through upregulating 2‐ketobutyric acid in the valine, leucine and isoleucine biosynthesis (VLIB) pathway that was closely related to threonine dehydratase and threonine and increasing expression of bacillomycin D synthase genes. Moreover, bacillomycin D could remarkably inhibit spore germination of Aspergillus flavus in rice. [ABSTRACT FROM AUTHOR]

Summary: l‐lactate is a conjugate base of α‐hydroxy acid, a key organic chemical in food processing, fermentation, biology and chemical industries. We are reporting for the first time a facile and rapid non‐enzymatic nanosensor for l‐lactate detection in tomato‐based products using 3‐aminophenylboronic acid (3‐APBA)‐added zinc oxide nanoparticles (ZnO NPs). 3‐APBA‐functionalised ZnO NPs have a selective and stable SPR intensity change at pH 5.5 to 7.5 and forms a reversible ester with bound l‐lactate revealing the wavelength shift from λ = 300 nm to 288 nm in UV‐VIS absorption spectrometry. In the spiked (2.5–20 mm) samples of tomato puree, absorption peak increased as per l‐lactate addition with the lower detection limit of 3.98 mm. l‐lactate binds with a trigonal form of 3‐boronate, thereby generating the tetrahedral complex. ZnO NPs stabilise the tetragonal complex. Nanosensor validated with standard HPLC. This method is useful for l‐lactate detection and alternates to conventional techniques. [ABSTRACT FROM AUTHOR]

Summary: We studied the in vitro prebiotic potential of five different cultivars of kiwifruit including the green‐fleshed ‘Hayward’ and ‘Zesh004’ and the gold‐fleshed ‘Hort16A’, ‘Zesy002’ and ‘Zesy003’. The kiwifruit (25 g fresh weight equivalent) were subjected to simulated gastrointestinal digestion before fermentation for 16 h with faecal microbiota from ten individual donors. Microbial metabolites including lactate were quantified while changes in microbiome composition were determined by 16S rRNA sequencing. Lactate concentrations were highest with ‘Hayward’ (P = 0.01) and correlated with the amount of the kiwifruit fibre and polyphenols, chlorogenic acid and cryptochlorogenic acid. All the kiwifruit behaved similar to inulin in increasing the relative abundance of Bifidobacterium (P < 0.001), but unlike inulin, significantly (P < 0.001) increased the abundances of Ruminococcaceae and decreased Bacteroides. In comparison with inulin, the green‐fleshed kiwifruit selectively increased Lachnospira (P = 0.008) while the gold‐fleshed kiwi fruit increased Akkermansia (P < 0.001). These data suggest that the fibre and polyphenol content of the kiwifruit play a role in modulating gut microbial metabolism. Further clinical studies with these kiwifruit cultivars are required to confirm the potential prebiotic benefits that may be achieved by normal dietary intervention. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the effect of calcium chloride and calcium lactate pretreatments at different concentrations (1, 1.5 and 2% w/v) on enzymatic browning of clingstone and freestone peaches following high-pressure processing ( HPP) at 200 MPa for 10 min. Proton nuclear magnetic resonance (1H- NMR) relaxometry indicated that following calcium pretreatment and HPP, both peach types had lower percentages of water in the vacuole compartment and a simultaneous increase in the percentage of water in the cytoplasm compartment. Calcium pretreatment of freestone peaches did not affect the development of browning, regardless of the form of calcium or the concentration, whereas calcium lactate pretreatment undesirably enhanced clingstone peach discoloration. Calcium pretreatments have the potential to reduce the loss of cell integrity that results from HPP; however, in this study, the effect was not sufficient to inhibit the interaction between the polyphenol oxidase enzyme that catalyses browning and its substrates. [ABSTRACT FROM AUTHOR]

Formation of extracts and fermentable sugars during mashing can be limited by incomplete starch gelatinisation. The aim of this research was to develop mashing programme for 100% teff malt as a potential raw material for gluten-free lactic acid-fermented beverage. Isothermal mashing at temperatures ranging between 60 and 84 °C was conducted, and the highest extract (85%) was observed for the wort samples produced at temperatures higher than 76 °C. Sixty-minute rest at 71 °C resulted in higher fermentable sugars than other tested conversion rest temperatures. Inclusion of lower mashing-in temperature in the mashing programme also substantially improved the concentrations of free amino nitrogen (128 mg L−1) and fermentable sugar (58 g L−1) in the final wort. Therefore, 30-min rest at 40 °C followed by 60-min rest at 71 °C and 10-min rest at 78 °C was found to be a suitable mashing programme for teff malt. [ABSTRACT FROM AUTHOR]