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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]

Fresh-cut ' Big Top' nectarines were dipped in 2% (w/v) ascorbic acid-1% (w/v) calcium lactate and stored at 4 °C for up to 12 days in 10 kPa O2- and 10 kPa CO2-modified atmosphere packaging (MAP). The used microperforated plastic film allowed O2 and CO2 concentrations to reach steady values from the fifth day in storage onwards. Samples stored in MAP after chemical dipping showed the highest visual quality score, slight browning symptoms, increment in firmness and very low ethanol and acetaldehyde content. The chemical dipping also increased antioxidant capacity, probably due to the effect of ascorbic acid. The results suggested that the control of yeasts was mainly exerted by MAP, whereas only a slight effect was achieved by the chemical dipping. Therefore, MAP plus ascorbic acid/calcium lactate dipping was the best combination to preserve phytochemical content, antioxidant capacity and microbiological safety of fresh-cut nectarines during storage. [ABSTRACT FROM AUTHOR]

This study explored the effects of calcium chloride ( Ca Cl2) and calcium lactate ( Ca- L) pretreatments prior to osmotic dehydration on physicochemical characteristics and consumer acceptance of dried papaya. Three different calcium concentrations [0.5, 1.5 and 2.5% (w/v)] were applied to samples before they were soaked in a 30 °Brix sucrose solution and subsequently dried at 70 °C. The results showed that the dried samples treated with calcium exhibited significantly lower moisture content, water activity, apparent density and shrinkage, while volume was higher when compared to the control. Calcium applications did not obviously influence sugar content of samples and maintained the quality of dried papaya in terms of colour and textural characteristics. Calcium chloride at 2.5% (w/v) was found to particularly impart undesirable bitterness to the dried papaya. In contrast, using 2.5% (w/v) Ca- L provided the best acceptance scores. Thus, the use of Ca- L could be an alternative to Ca Cl2 in the pretreatment of fruits prior to drying as it offers improved quality. [ABSTRACT FROM AUTHOR]

The effects of different concentrations of calcium hydroxide [Ca(OH)2] and calcium lactate [C6H10O6Ca] on the functional and physical properties of extruded ( EF) and nixtamalised ( NF) blue maize flours were evaluated. Calcium source and concentration showed no significant effects on the EF expansion index. The water absorption index ( WAI) of EF decreased as the concentrations of both calcium sources increased, and NF with C6H10O6Ca had the lowest WAI. The thermal and pasting properties of NFs were higher than those of EF. NF with C6H10O6Ca showed the highest final viscosity (FinV), indicating less damage to the starch granules, and this was correlated with microscopic analysis. In contrast, the FinV of EFs was significantly affected by calcium source and concentration. Extrusion with 0.3% and nixtamalisation at 2.95% of C6H10O6Ca yielded high WAI value and the best rheological properties in maize flour, respectively. These results suggest the use of C6H10O6Ca in extrusion or nixtamalisation to produce blue maize flours for tortilla or snacks with antioxidants. [ABSTRACT FROM AUTHOR]

Changes in the aromatic composition as well as sensory characteristics in Verdejo white wines were analysed based on two factors: the winemaking methodology and the storing time of wine in bottles. The volatile components were determined by GLC-MS, and the sensory profile was designed and assessed according to the ISO 11035 standard. The results showed that when wines were made in oak barrels, either completely or partially, which means the wines were in contact with the lees, the levels of 1-octanol, ethyl heptanoate and ethyl decanoate were significantly affected ( P < 0.05); the softness sensation was also influenced ( P < 0.05). However, the amount of time the wines were stored in bottles significantly affected ( P < 0.05) the levels of 1-hexanol, ethyl heptanoate, ethyl octanoate, ethyl decanoate, hexyl acetate, isoamyl acetate and isoamyl lactate and also an odour note (tropical fruit). The compounds with higher OAV values belong to the groups of esters and fatty acids. For these reasons, the composition and the quality of the aroma of Verdejo white wines appear to be significantly affected both by use of oak barrels in winemaking and the time the wines are stored in bottles. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the effect of sodium lactate and sodium propionate, both in combination with sodium acetate, on strains of Listeria monocytogenes in artificially inoculated soft cheeses. Minas Frescal and Coalho cheeses, inoculated with a mix of L. monocytogenes 1/2a and Scott A, underwent two treatments: 2% (w/v) sodium lactate in combination with 0.25% (w/v) sodium acetate and 2% (w/v) sodium propionate in combination with 0.25% (w/v) sodium acetate. The samples were analysed immediately and after 7 days at 10 °C. The growth of the pathogen was inhibited in cheeses containing the salts of organic acids, and the effects of treatment were statistically significant ( P < 0.05). However, there was no difference between the types of treatment applied. Our data demonstrate that the effectiveness of the salts of organic acids depended on the initial concentration of L. monocytogenes and that a higher concentration of the salts is necessary to ensure sustained inactivation of target pathogens because they are weakly antilisterial when the soft cheeses are stored at 10 °C. [ABSTRACT FROM AUTHOR]

Chemical, microbial and sensory quality indices of raw and marinated sea urchin Paracentrotus lividus Lamark, 1816, were determined. Marinades were prepared using three different formulations and stored over a 75-day period at 6 °C, under vacuum and air (control) packaging conditions. Significant differences were found between chemical (pH, moisture, ash, NaCI, ammonia and lactic acid), microbial [pseudomonads (Ps), lactic acid bacteria (LAB) and yeast–moulds] and sensory analysis of three different marinated groups ( P < 0.05) during the storage period. The marinating process did not lead to significant differences in fatty acid, protein, fat and carbohydrate contents relative to raw sample. A notable decrease of the ω-3 per ω-6 ratio after marinating and during storage in both packages was observed. Ammonia concentration changes were found to be useful as index of freshness and decomposition of roe in storage. Shelf life of roe marinades at 6 °C was found to be 75 and 60 days under vacuum and air storage conditions respectively. [ABSTRACT FROM AUTHOR]

In the framework of the trend towards lowering the salt content in meat products, an experiment was set up to determine combined effect of reducing the salt content with 20% or 40% and adding 2% or 3% Purasal® Opti.Form PD 4 (a mixture of potassium lactate and sodium diacetate) on the shelf-life of a pre-packaged cooked meat product. By means of a challenge test with a mixture of two Lactobacillus sakei strains and a Leuconostoc mesenteroides strain, it was observed that use of lactate/diacetate mixture enabled a 40% reduction of the salt content in this cooked meat product, whereas the microbial shelf-life was significantly increased. [ABSTRACT FROM AUTHOR]

Biomass concentrations of the dairy starter culture Lactococcus lactis NZ133 were increased by the incorporation of an electrodialysis (ED) unit into a batch fermentation grown on 80 g lactose L−1. ED effectively removed the growth inhibitory metabolic end-product lactic acid (as lactate ions) and allowed continued growth beyond that achievable in normal batch fermentation. However, biomass yields per unit lactose were reduced by the probable concomitant loss of other ionic species and nutrients essential for growth. Repeated fed-batch with end-batch ED introduced to minimise this putative loss of nutrients, yielded a final biomass concentration of 12.4 g L−1 on 120 g lactose L−1 medium (biomass yield = 0.05 g g−1), which was appreciably below that observed for standard batch fermentations (biomass yield = 0.12 g g−1). In addition to the reduced yields, the lactic acid production activity of the cells progressively decreased with the increase in number of ED cycles. [ABSTRACT FROM AUTHOR]

Ten strains of lactic acid bacteria were isolated from a dry fermented sausage and tested for stimulation or inhibition of the viability of Vero and myeloma cells. They did not significantly affect the viability of Vero cells but two isolates (CBL/H and CBL/K) showed a strong and moderate inhibition of the myeloma cell viability (at 108 CFU mL−1, 17.6 and 33.2%, respectively, survival of myeloma cells). The isolates were identified asLactobacillus sakeiby DNA sequencing of the 16S rRNA products of a polymerase chain reaction. No protective effect was found, at the concentrations used, against cytotoxicity of N-nitrosamines. To test the effect ofL. sakeiCBL/H and CBL/K on cytokine production [tumour necrosis factor alpha (TNF-α), interleukin-1β (IL-1β) and interleukin-8 (IL-8)], the human macrophage cell line (THP-1) was cultured in the presence and absence of lipopolysaccharide (LPS).Lactobacillus sakeiCBL/H and CBL/K induced IL-1β and IL-8 release when cells were stimulated with and without LPS. However there was TNF-α release only in the presence of the LPS. [ABSTRACT FROM AUTHOR]

In order to investigate the potential of magic angle spinning nuclear magnetic resonance (MAS NMR) in the elucidation of post-mortem metabolism in muscle biopsies, simultaneous 1H and 31P MAS NMR measurements were made continuously on post-mortem (20 min to 24 h) muscle longissimus samples from rabbits. The animals had either been or not been given adrenaline (0.5 mg kg−1 4 h pre-slaughter) to deplete stores of muscle glycogen. The intracellular pH was calculated from 1H spectra, and the post-mortem rate of formation of lactate was followed and quantified. Comparison of measurements made on muscle samples from rabbits treated with adrenaline with measurements made on muscle samples from untreated rabbits revealed significant effects of adrenaline treatment on both pH (pH24 h = 6.42 vs. pH24 h = 5.60) and formation of lactate (16 mmol g−1 vs. 65 mmol g−1). The 31P NMR spectra were used to follow the rate of degradation of ATP and phosphocreatine. The present study clearly shows that MAS NMR has potential for the study of post-mortem energy metabolism. [ABSTRACT FROM AUTHOR]

Tomato waste is an important source of natural carotenoids. This study was carried out to assess the extractability of tomato waste carotenoids in different organic solvents and to optimise the extraction parameters (type of solvent, extraction time, temperature and extraction steps) for maximum yield. Among other solvents, we tested a new environmentally friendly one, ethyl lactate, which gave the highest carotenoid yield (243.00 mg kg dry tomato waste) at 70 °C, compared to acetone (51.90 mg kg), ethyl acetate (46.21 mg kg), hexane (34.45 mg kg) and ethanol (17.57 mg kg). The carotenoid recovery was significantly ( P < 0.05) affected by the number of extraction steps and temperature in all solvents. Mathematic equations predicted rather satisfactorily ( R = 0.89-0.93) the rate of carotenoid extraction in the above-mentioned solvents. Carotenoid concentration increased with time, approaching a quasi-saturated condition at approximately 30 min of extraction. [ABSTRACT FROM AUTHOR]