Assessment of hydrolysis of cheese whey and use of hydrolysate for bioproduction of carotenoids by Sporidiobolus salmonicolor CBS 2636

BACKGROUND: The increasing industrial demand for carotenoids has led to growing interest in their bioproduction. The need to reduce production costs has encouraged the use of low‐cost agroindustrial substrates. In this context, this work studied the pretreatment of Mozzarella cheese whey and the use of the pretreated whey as fermentation medium for the bioproduction of carotenoids by Sporidiobolus salmonicolor CBS 2636. RESULTS: Bioproduction was carried out in an orbital shaker using a 10 mL L^?1 inoculum, incubation at 25 °C and a stirring rate of 180 rpm for 120 h in a non‐illuminated environment. The carotenoids were recovered using liquid N₂ combined with dimethyl sulfoxide for cell rupture and an acetone/methanol mixture (7:3 v/v) for extraction. The maximum concentration of total carotenoids obtained was 590.4 µg L^?1 in a medium with 900 g L^?1 cheese whey hydrolysate and 4 g L^?1 K₂HPO₄ at 180 rpm, 25 °C and pH 4. CONCLUSION: The use of enzyme‐hydrolysed cheese whey was more effective in carotenoid bioproduction by S. salmonicolor CBS 2636 than the use of acid‐hydrolysed cheese whey. The concentration of total carotenoids obtained with the enzymatic hydrolysate was six times higher than that obtained with the acid hydrolysate. Copyright © 2009 Society of Chemical Industry     

Apple pomace ultrafiltration sludge – A novel substrate for fungal bioproduction of citric acid: Optimisation studies

Ever-growing demand for citric acid (CA) and urgent need for alternative sources has served as a driving force for workers to search for novel and economical substrates. Submerged fermentation was conducted using apple (Malus domestica) pomace ultrafiltration sludge as an inexpensive substrate for CA bioproduction, using Aspergillus niger NRRL567. The crucial parameters, such as total suspended solids and inducer concentration, were optimised by response surface methodology for higher CA production. The optimal CA concentrations of 44.9 g/100 g and 37.9 g/100 g dry substrate were obtained with 25 g/l of initial total solids and 3% (v/v) methanol and 25 g/l of total solids and 3% (v/v) ethanol concentration, respectively, after the 144 h of fermentation. Results indicated that total solids concentration, and methanol as an inducer, were effective with respect to higher CA yield and also indicated the possibility of using apple pomace sludge as a potential substrate for economical production of CA.     

Rheological Studies During Submerged Citric Acid Fermentation by Aspergillus niger in Stirred Fermentor Using Apple Pomace Ultrafiltration Sludge

Rheological profile studies for apple pomace ultrafiltration sludge (APS) broth with filamentous fungus, Aspergillus niger NRRL-567 during citric acid (CA) fermentation are reported for the biomass developed in a 7.5 l bench scale fermentor. CA bioproduction of 23.67?±?1.0 g/l APS and 40.34?±?1.98 g/l APS was obtained in control (120 h) and in treatment with inducer, MeOH 3% (v/v), respectively, after 132 h of fermentation by A. niger NRRL 567. The rheological properties of the fermentation broth including pellets were analyzed. The control demonstrated non-Newtonian pseudoplastic behaviour due to more filamentous growth. However, in treatment supplemented with inducer (methanol), pellet form was observed during fermentation with less viscous non-Newtonian broths. The power law model was followed with good confidence of fit (77.8–88.9%) throughout the fermentation in treatment with MeOH as an inducer. However, power law was followed with moderate fit of confidence (65.3–75.9%) at the beginning of fermentation until 48 h and later followed a good confidence of fit (75.9–88.2%) until 144 h of fermentation in control. Important rheological changes occurred in the broth during maximal CA production phase along with increase in biomass in the pelleted mycelium form.     

Xylitol bioproduction from wheat straw: hemicellulose hydrolysis and hydrolyzate fermentation

A 2² central composite design with five center points was performed to estimate the effects of temperature (120, 130 and 140 °C) and acid loading (100, 150 and 200 mg g^?1) on the yield of monomeric xylose recovery from wheat straw hemicellulose (Y_S/RM). Under the best hydrolysis condition (140 °C and 200 mg g^?1), a Y_S/RM of 0.26 g g^?1 was achieved. After vacuum concentration and detoxification by pH alteration and active charcoal adsorption, the hydrolyzate was used as source of xylose for xylitol bioproduction in a stirred tank reactor. A xylitol production of 30.8 g L^?1 was achieved after 54 h^?1 of fermentation, resulting in a productivity (Q_P) of 0.57 g L^?1 h^?1 and bioconversion yield (Y_P/S) of 0.88 g g^?1. The maximum specific rates of xylose consumption and xylitol production were 0.19 and 0.15 g g^?1 h^?1, respectively. Copyright © 2006 Society of Chemical Industry     

Characterisation of wines and distilled spirits from melon (Cucumis melo L.)

Melon fermentation and distillation was studied with a view to produce melon spirits. Three different substrates were obtained from melon (Cucumis melo L.). Sugar concentration was around 60–70 g L^?1 and the pH between 4.6 and 5.2. The substrates were clarified and then fermented at one of two pH levels at 20 °C. A commercial Saccharomyces cerevisiae starter culture was used to obtain melon wines with an alcohol concentration of 3.8–5.8% (v/v). The melon wines were distilled in a distillation column to yield distillates with an alcohol content of 33–60% (v/v). The major volatiles in the melon wines and in the distillates were analysed by gas chromatography (GC). The results demonstrated that melon could be a good substrate of fermentation and distillation but also yielded significant differences in the volatiles analysed in the different melon wines and distillates obtained from the different substrates in the different conditions of the experiment. Fermentation pH greatly affected the methanol, acetaldehyde, and butanol contents and thus the final quality of the spirits produced.     

Carotenoids production from a newly isolated <Emphasis Type="Italic">Sporidiobolus pararoseus</Emphasis> strain by submerged fermentation

This work aimed at evaluating the total carotenoids production by a newly isolated Sporidiobolus pararoseus. Bioproduction was carried out in an orbital shaker, using 10% (w/v) of inoculum (25 °C, 180 rpm for 35 h), incubated for 120 h in a dark room. Liquid N₂ and dimethylsulphoxide (DMSO) were used for cell rupture, and carotenoids were extracted with a solution of acetone/methanol (7:3, v/v). Optimization of carotenoids bioproduction was achieved by experimental design technique. Initially, a Plackett–Burman design was used for the screening of the most important factors, after the statistical analysis, a complete second-order design was carried out to optimize the concentration of total carotenoids in a conventional medium. Maximum concentration of 856 μg/L of total carotenoids was obtained in a medium containing 60 g/L of glucose, 15 g/L of peptone, and 15 g/L of malt extract, 25 °C, initial pH 4.0 and 180 rpm. Fermentation kinetics showed that the maximum concentration of total carotenoids was reached after 102 h of fermentation and that carotenoids bioproduction was associated with cell growth.     

Chemical characteristics of Śliwowica Łącka and other plum brandies

BACKGROUND: ?liwowica ??cka is a strong, distilled, home‐made plum brandy produced in a submontane region of Poland. The aim of the present study was to determine the chemical composition of this alcoholic beverage (samples from the years 2001–2004) and compare it with that of other plum brandies. Gas chromatography and spectrophotometry methods were used to detect major volatile components. RESULTS: Home‐made Polish plum brandies generally contained more ethanol (64.7–72.5% v/v), methanol (5.59–8.74 g L^?1100°) and butanol (32–335 mg L^?1100°) and less isobutanol (406–491 mg L^?1100°), pentanol (4.3–14.9 mg L^?1100°) and 2‐phenylethanol (61–68 mg L^?1100°) than other samples. The amyl alcohols/1‐propanol and isobutanol/1‐propanol ratios might be used as indices to distinguish spontaneously fermented plum brandies from those produced by monoculture. Statistically significant differences (P < 0.01) were found in the plum brandy sensory characteristics examined. Total sensory scores of Polish plum brandies ranged between 12.0 and 14.3, while Slovakian Slivovica received the highest score (16.7). CONCLUSION: The results showed that plum brandies produced in the ??cko area are characterised by a similar and original chemical composition that results mainly from spontaneous fermentation as well as traditional production technology. Copyright © 2007 Society of Chemical Industry     

Microfiltration of whey proteins adsorbed on yeast cells

Soluble whey proteins (WPs), adsorbed on yeast cells, were recovered by a crossflow microfiltration (MF) technique using a cellulose nitrate membrane with a pore size of 0.45 μm. The crossflow velocity was 1.5 m s^?1 with a transmembrane pressure of 200 kPa at 25 °C. A series of protein rejections occured at various pH values ranging from 2 to 8. WPs adsorbed more on to yeast cells at low pH (pH < 4) than at high pH values, probably because they were positively charged at low pH. It was also shown that permeate flux increased and Modified Membrane Fouling Index values decreased at low pH levels. When the yeast concentration was 50 g L^?1, the flux decreased five times compared with that in the absence of yeast. Protein recovery increased with increasing yeast concentrations. The highest protein recovery was found to be 85% at a yeast concentration of 50 g L^?1 at a steady state flux rate of 10^?6 m s^?1 at 25 °C. When diluted solutions of whey were used, the same rejection of protein, adsorbed on yeast cells, was achieved at ten times lower amounts of yeast cells. This technique not only provides for the recovery of protein but also may give rise to the direct use of yeast cells, which are rich in protein, in the baking industry. WPs absorbed by yeast cells can be used to produce nutritionally rich products in areas where yeasts have been already used.     

Evaluation of the conditions of carotenoids production in a synthetic medium by Sporidiobolus salmonicolor (CBS 2636) in a bioreactor

This work studied the cultivation conditions for the production of carotenoids by Sporidiobolus salmonicolor (CBS 2636) in a bioreactor. A Plackett–Burman design was used for the screening of the most important factors, followed by a complete second order design, to maximise the concentration of total carotenoids. The maximum concentration of 3425.9 μg L^?1 of total carotenoids was obtained in a medium containing 80 g L^?1 glucose, 15 g L^?1 peptone and 5 g L^?1 malt extract, with an aeration rate 1.5 vvm, 180 r.p.m., 25 °C and an initial pH of 4.0. Fermentation kinetics showed that the maximum concentration of total carotenoids was reached after 90 h of fermentation. Carotenoid bio‐production was partially associated with cell growth. The specific carotenoid production (Y_P/X) was 238 μg carotenoids/g cells, whereas Y_P/S (substrate to product yield) was 41.3 μg g^?1. The specific growth rate (μ_x) was 0.045 h^?1. The highest cell and total carotenoid productivity were 0.19 g L^?1 h^?1 and 56.9 μg L^?1 h^?1, respectively.     

Detoxification of Aflatoxin B1 and M1 by Lactobacillus acidophilus and prebiotics in whole cow's milk

The detoxification ability of Lactobacillus acidophilus and prebiotics was evaluated by a Plackett‐Burman Design to examine the reduction of concentration and bioaccessibility of aflatoxin B₁ (AFB₁) and M₁ (AFM₁) in artificially contaminated whole cow's milk. Six variables were evaluated: AFB₁ (3.25–6.0 μg L^?1) or AFM₁ (1.0–2.0 μg L^?1) concentration; incubation time (0–6 h); and inulin, oligofructose, β‐glucan, and polydextrose concentrations (each between 0.00 and 0.75%). All runs achieved reductions of AFB₁ (13.53–35.53%) and AFM₁ (17.65–71.52%). Comparing with the positive control, the AFB₁ bioaccessibility ranged from 23.68 to 72.67% and for AFM₁ was 0%. The probiotic, isolated or combined with prebiotics, was efficient in mycotoxin reduction, while the combination of the two reduced the mycotoxin bioaccessibility. The best experimental condition was the highest concentration of AFB₁ (6.5 μg L^?1) and AFM₁ (2.0 μg L^?1), incubation time of 0 h and the addition of probiotic and inulin (0.75%).     

Improvement of L(+)‐lactic acid production from cassava wastewater by Lactobacillus rhamnosus B 103

BACKGROUND: L (+)‐Lactic acid is used in the pharmaceutical, textile and food industries as well as in the synthesis of biodegradable plastics. The aim of this study was to investigate the effects of different medium components added in cassava wastewater for the production of L (+)‐lactic acid by Lactobacillus rhamnosus B 103. RESULTS: The use of cassava wastewater (50 g L^?1 of reducing sugar) with Tween 80 and corn steep liquor, at concentrations (v/v) of 1.27 mL L^?1 and 65.4 mL L^?1 respectively led to a lactic acid concentration of 41.65 g L^?1 after 48 h of fermentation. The maximum lactic acid concentration produced in the reactor after 36 h of fermentation was 39.00 g L^?1 using the same medium, but the pH was controlled by addition of 10 mol L^?1 NaOH. CONCLUSION: The use of cassava wastewater for cultivation of L. rhamnosus is feasible, with a considerable production of lactic acid. Furthermore, it is an innovative proposal, as no references were found in the scientific literature on the use of this substrate for lactic acid production. Copyright © 2010 Society of Chemical Industry     

Development of a chemometric-assisted deep eutectic solvent-based microextraction procedure for extraction of caffeine in foods and beverages

ABSTRACT

In this research article, a novel and green deep eutectic solvent-based microextraction (DES-ME) procedure based on chemometric-assisted (CA) optimization was developed for the extraction of caffeine in foods and beverages prior to its spectrophotometric determination. Ultrasound was used to accelerate the extraction of caffeine. Deep eutectic solvents (DES), prepared in an ultrasonic bath at 20–60 min for 60–80°C, were used as extraction solvents. The important experimental variables (pH, DES amount, temperature, sonication time and metal concentration) were modelled and optimized using response surface methodology (RSM) based on central composite design (CCD). Under the optimum conditions, the proposed method allowed the determination of caffeine with limits of detection (LOD, 3s_blank/m) and quantification (LOQ, 3s_blank/m) of 7.5 and 25.0 µg L^?1, respectively. For 40 µg L^?1 and 100 µg L^?1 of caffeine (n = 5), relative standard deviations (RSDs%) and recoveries% were 1.2–1.6% and 96.7–98.2%, respectively. Validation studies (accuracy, precision, trueness, reliability and selectivity) of the method were performed before the analysis of real samples. The results showed that the combination of the CCD with the DES-ME can be considered as a new perspective for the extraction and determination of caffeine in foods and beverages.     

Batch kinetics and modelling of ethanolic fermentation of whey

The fermentation of whey by Kluyveromyces marxianus strain MTCC 1288 was studied using varying lactose concentrations at constant temperature and pH. The increase in substrate concentration up to a certain limit was accompanied by an increase in ethanol formation, for example, at a substrate concentration of 10 g L^?1, the production of ethanol was 0.618 g L^?1 whereas at 50 g L^?1 it was 3.98 g L^?1. However, an increase in lactose concentration to 100 g L^?1 led to a drastic decrease in product formation and substrate utilization. The maximum ethanol yield was obtained with an initial lactose concentration of 50 g L^?1. A method of batch kinetics was utilized to formulate a mathematical model using substrate and product inhibition constants. The model successfully simulated the batch kinetics observed at S₀ = 10 and 50 g L^?1 but failed in case of S₀ = 100 g L^?1 because of strong substrate inhibition.     

Anthocyanin profile in berry skins and fermenting must/wine, as affected by grape ripeness level of Vitis vinifera cv. Shiraz/R99

The release of anthocyanin compounds from berry skins into the wine is affected by several viticulture and oenological practices. Ripeness level seems to play a significant role. The study aimed to evaluate the extraction kinetics of individual anthocyanins from grape skins into wine under controlled conditions of small-scale vinification of Shiraz grapes, harvested at three ripeness levels (23, 25 and 28°Brix). The anthocyanin profile of intact berry skins, fermenting musts/wines and crushed skins during the period between crushing and pressing was analysed by HPLC. Ripeness level greatly impacted on the skin?/?juice ratio (ranging from 169?± 4.5?g?L^?1 at 23°B, 185?±?7.2?g?L^?1 at 25°B and 256?±?10.7?g?L^?1 at 28°B) and on grape anthocyanin concentration (ranging from 0.80?±?0.13?g?kg^?1 at 23°B, 0.78?±?0.07?g?kg^?1 at 25°B and 1.21?±?0.13?g?kg^?1 at 28°B) and profile (%) at harvest. In addition, it affected the rate and amount of individual anthocyanin extraction from skins into wine and their transformation during fermentation, consistent with the relevant chemical group classification (3-glucoside, 3-acetyl-glucoside, 3-p-coumaroyl-glucoside). At pressing, the anthocyanin concentration of the three wines was similar (319?mg?L^?1, on average), but the anthocyanin profile was different, particularly the ratio of 3-glucoside?/?3-p-coumaroyl-glucoside derivatives, which was on average 3.55 at 23°B and 25°B and 2.6 at 28°B. Viticultural choices, such as to harvest earlier or later, influencing the chemical and physical composition of the berries, may influence the extraction kinetics of individual anthocyanins and their destiny in the fermenting must, offering to winemakers different basic wines suitable for the production of different wine products. These findings are valuable to improve viticultural and oenological practices for Shiraz wine production, allowing the improvement of wine quality and the purposeful creation of different styles of wine.     

A Rapid Quantification of β-Carotene in Fruits and Vegetables by Dispersive Liquid–Liquid Microextraction Coupled with UV–Vis Spectrophotometry: Optimized by Response Surface Methodology

A simple, fast, and efficient method consisted of optimized dispersive liquid–liquid microextraction (DLLME) followed by UV–vis spectrophotometry was developed for determination of β-carotene in fruits and vegetables. Chloroform and methanol were chosen as extraction and disperser solvents, respectively. The extraction process was optimized using a central composite design (CCD) with the optimum points of 115 μL for volume of extraction solvent and 6.5 % (w/v) for salt concentration. Under the optimal conditions, the relative standard deviation (RSD, C?=?500 μg L^?1, n?=?5), limit of detection (LOD), linear dynamic range (LDR), and coefficient of determination (R²) were 1.08 %, 2 μg L^?1, 50–1,500 μg L^?1, and 0.991, respectively. The present method consisted of a simple and fast sample preparation procedure without any antioxidant addition, saponification, and purification was used.     

Natural deep eutectic solvent-based ultrasound-assisted-microextraction for extraction,pre-concentration and analysis of methylmercury and total mercury in fish and environmental waters by spectrophotometry

ABSTRACT

In this study, a simple, pH-controlled, and natural deep eutectic solvent-based microextraction (NADES-ME) procedure is proposed before the spectrophotometric analysis of methylmercury (MeHg) and total mercury in fish and environmental waters. The method is based on charge-transfer sensitive ion-pair formation between MeHg and 3-(dimethylamino)-7-(methylamino)phenothiazin-5-ium chloride (Azure B – AzB) in the presence of chelating citrate-phosphate buffer at pH 6.0, and then extraction of the formed ion-pair complex with the NADES. The important variables affecting extraction efficiency were evaluated and optimised. At optimal conditions (300 µL of 1.0 × 10^?3 mol L^?1 AzB, 600 µL NADES (betaine-sorbitol, 1:3) containing 10% water (v/v) as extractant, 375 µL acetonitrile as aprotic solvent for sonication of 7 min at power of 300 W/40 kHz, and centrifugation at 4000 rpm for 3 min, respectively), the figures of merit for MeHg include a good linearity in the concentration range of 0.7–340 µg L^?1, limits of detection and quantification of 0.25 and 0.83 µg L^?1, and pre-concentration and sensitivity enhancement factors of 120 and 95, respectively. Figures of merit for total Hg (iHg, where Hg₂²⁺ ions are predominantly present in natural oxygen-rich waters such as freshwaters and seawater as well as elemental Hg and Hg²⁺ ions at very low amounts) after pre-oxidation at pH 5.0 include linearity range of 3–270 µg L^?1 with limits of detection and quantification of 0.92 and 3.10 µg L^?1, and pre-concentration and sensitivity enhancement factors of 120 and 35, respectively. The reliability (with recovery of 92–98.7% and RSD of 1.9–5.5%) was statistically validated by analysis of two standard reference materials (SRMs) with and without spiking. The method was successfully applied to the speciation analysis of total Hg, iHg and MeHg in fish and environmental waters.     

Xanthan gum produced by Xanthomonas campestris from cheese whey: production optimisation and rheological characterisation

BACKGROUND: This aim of this study was the production and rheological characterisation of xanthan gum by Xanthomonas campestris pv. mangiferaeindicae IBSBF 1230 using industrial media and experimental design techniques in a bench bioreactor. RESULTS: The optimised conditions for the production of xanthan starting with 900 mL of cheese whey were 1 g L^?1 magnesium sulphate, 20 g L^?1 potassium phosphate, 28 °C temperature and initial pH 7.2 at 390 rpm agitation and 1.5 vvm aeration, resulting in 36 g L^?1 gum in 72 h. The highest viscosity obtained in the production optimisation study was 1831.34 mPa s at 25 °C with 30 g L^?1 gum. The use of CaCl₂ resulted in the highest solution viscosity under conditions of 25 °C, 1 g L^?1 salt and 46.8 g L^?1 gum, with a value of 1704.53 mPa s. CONCLUSION: In this study, cheese whey, a by‐product of the dairy industry, was used as substrate in the production of xanthan gum, a valuable product in food applications, with optimised high gum production in a bioreactor and a wide range of viscosity values. Copyright © 2009 Society of Chemical Industry     

Carotenoid and anthocyanin contents of grains of Brazilian maize landraces

BACKGROUND: Carotenoid and anthocyanin contents of 26 maize landraces cultivated in southern Brazil were determined to evaluate their potential as natural colorants or functional food ingredients. RESULTS: The major carotenoids detected in the whole grain flour were zeaxanthin and lutein. Anthocyanins of landraces with purple starchy endosperm (Lingua de Papagaio and Mato Grosso Palha Roxa) were more extractable in methanol–HCl (1%, v/v), exhibiting 2.45 and 0.94 g kg^?1 of whole grains flour, respectively. In contrast, butanol–HCl (30%, v/v) was more effective for the extraction of anthocyanins from the purple‐colored landraces Roxo 29 and Roxo 41; genotypes with pigments localized in the outer parts (pericarp) of grains (2.60 and 2.19 g kg^?1). The Roxo 41 landrace showed the highest concentration of pigments, e.g. 11.72 10^?3 g kg^?1 of total carotenoids and 2.16 g kg^?1 of total anthocyanins. Similarly, the yellow‐colored MPA 1 and the purple‐colored Roxo 29 landraces showed prominent amounts of carotenoids (10.86 10^?3 g kg^?1) and anthocyanins (2.60 g kg^?1), respectively. CONCLUSION: Our findings suggest that the colored grains of maize landraces studied may hold promise for the development of grain‐based functional foods or natural colorants regarding their carotenoid and anthocyanin contents and as genetic resource in breeding programs. Copyright © 2011 Society of Chemical Industry     

Caseinate at Low Temperatures: Calcium Use in β-Casein Extraction by Microfiltration

Calcium-induced modifications of 2% sodium caseinate at 4°C and β-casein extraction by microfiltration on membranes were studied. Pore diameters and tangential flow rates were investigated. Calcium addition up to 3 g.L^?1 was followed by a pH decrease, particle size increase and a shift of casein towards colloidal state. The higher purity of β-casein in the soluble fraction was obtained between 1 and 1.5 g.L^?1 of added calcium. Increasing calcium to 1 g.L^?1 induced hydraulic resistance increase, and higher retention of β-casein. Particle size increases were related to physicochemical modifications induced by the calcium addition.     

Effect of calcium chloride on mechanical properties and microbiological characteristics of cv. Conservolea naturally black olives fermented at different sodium chloride levels

The effect of calcium chloride (CaCl₂)(5 gL^?1) and sodium chloride (NaCl) concentration (40, 60 and 8 gL^?1) on the microbiological and mechanical properties of naturally black olives of cv. Conservolea in brines was studied. In 40 and 60 g L^?1 brines the growth of lactic acid bacteria was favoured over that of yeasts, resulting in rather complete lactic acid fermentation as indicated by high free acidity (9.8–11.5 g lactic acid L^?1) and low pH (3.7–3.8). At 80 g L^?1 brine, yeasts were the dominant members of the microflora, rendering a product with lower acidity (8 g lactic acid L^?1) and higher pH (4.3–4.5). In the presence of CaCl₂ there was a consistent increase in the depth of the peripheral region in which cell wall breakage occurred. When cells separated, perforated walls were observed at sites associated with plasmodesmata. The flesh was strongest and stiffest when CaCl₂ was added to olives treated with 40 g L^?1 brine, consistent with cell wall breakage being the predominant mode of failure. The only observed effect on the mechanical properties of the skin was a stiffening at 60 g L^?1 brine on addition of CaCl₂. Copyright © 2007 Society of Chemical Industry