Stability Of Beverages Research Articles

Improvements in emulsion stability of dairy beverages treated by high pressure homogenization: A pilot-scale feasibility study

The impact of high pressure homogenization (HPH) on physical characteristics and emulsion stability of nutritional formulations were evaluated on a pilot scale HPH unit. Two products of industrial interest were used for these experiments. Manufactured formulations were analyzed using material characterization methods as particle size distribution, microscopy and dynamic mechanical spectra, compared to a control formula manufactured with conventional homogenization and heat treatments. Dynamic rheological measurements as strain and frequency sweeps exhibited increased product stability in parallel to increased homogenization pressures. Homogenization at elevated pressures yielded more shear thinning fluids evidenced by increased viscosities at low shear rates, ten fold greater compared to the control treatment, further evidence to increased physical stability. Experimental findings revealed the existence of a threshold pressure (100–150 MPa) for both formulations exhibiting significant correlation with product quality and physical stability. The study outcomes presents an opportunity for reducing stabilizer concentration in dairy beverages; in addition to shelf life and physical stability improvement for formulations treated at increased homogenization pressures.

Enhanced stability of anthocyanin-based color in model beverage systems through whey protein isolate complexation

Anthocyanins are often used in functional foods and beverages as colorants and nutraceuticals. However, these natural compounds may undergo chemical degradation during storage leading to color fading and loss of bioactivity. In particular, vitamin C (l-ascorbic acid) is known to accelerate anthocyanin degradation. In this study, the influence of various food-grade biopolymers on the physical and chemical stability of model beverages containing anthocyanin (0.025%), ascorbic acid (0 or 0.05%), and calcium salt (0 or 0.01%) was examined under accelerated conditions (40°C for 7days). Four biopolymers (1%) were examined for their potential to inhibit anthocyanin degradation: native whey protein; denatured whey protein; citrus pectin; and beet pectin. The physical stability was determined by measuring changes in absorbance, color, and visual appearance. Solutions containing anthocyanin and calcium salt (0 or 0.01%) were stable throughout storage, while those with added ascorbic acid were the least stable. The addition of biopolymers, particularly heat denatured whey protein, significantly enhanced the stability of the anthocyanin during storage. Fluorescence quenching studies showed that the anthocyanin may have formed complexes with the whey protein through hydrogen bonding that resulted in their enhanced stability in the presence of ascorbic acid. This study provides information that may improve the stability of anthocyanins in food and beverage systems.

Studies on effect of irradiation on functional properties of two ready-to-drink appetizer beverages and their shelf lives

Purpose – The purposes of this paper are to extend the shelf life of juice/fluids and reduce the thermal damage of their functional components. Thermal processing is a universal method used to extend the shelf lives of juice/fluids. However, combination processing thought to be beneficial in extending the shelf life with least possible thermal damage. The shelf life of the two thermally processed appetizer beverages, i.e. ginger beverage and karpurvalli beverage was established up to six months. Design/methodology/approach – Both appetizer beverages were processed using irradiation in combination with heat treatment. A short thermal treatment at 95°C for 5 minutes was given to the bottled beverages, and these were then irradiated with different dosages of 1, 2 and 3 kGy. The samples were stored at room temperature (18-33°C), as well as at 37°C and periodically analysed for changes in pH, acidity, TSS, browning index, antioxidant activity and gingerol/carvacrol contents and for their microbiological quality. Findings – The results revealed that in both products, the antioxidant activity and the gingerol/carvacrol content reduced, making these microbiologically safe up to eight months. However, combination of irradiation was not found suitable for the appetizer beverages due to more than 50 per cent losses in the functional components. Research limitations/implications – The combination of thermal and irradiation processing was effective to ensure microbial safety and extend the shelf life of beverages. However, it may not be suitable for preserving all functional properties. Originality/value – The outcome is result of original work done, and information provided can be a preamble to the researchers targeting improved stability of functional beverages.

Production of a high level of laccase by submerged fermentation at 120-L scale of Cerrena unicolor C-139 grown on wheat bran

Submerged fermentation in a stirred bioreactor of the white rot fungus Cerrena unicolor C-139 was done at a 120-L scale in the presence of wheat bran as a cheap lignocellulosic substrate for fungus growth and laccase production. Enzyme monitoring showed that laccase production started after 2days of cultivation, attaining a maximum activity of 416.4U·mL−1 at day 12 of fermentation. After treatment of culture liquid by successive micro- and ultrafiltration (5kDa), a liquid concentrate containing 22203176units of laccase was obtained. Obtaining large amount of laccase is essential for various industrial applications, including detoxification of industrial effluents, textile and petrochemical industries, polymer synthesis, bioremediation of contaminated area, stabilization of beverages, production of cosmetics, manufacture of anti-cancer drugs, and nanobiotechnology. The cultivation method and the fungal strain used here provided a substantial amount of enzyme produced at a price lower than 0.01€ cent/unit enzyme.

Effect of protein oxidation on the stability of peanut beverage

Protein oxidation of peanut beverage and their stability during the storage were investigated. To further investigate the relationship between protein oxidation and peanut beverage stability, peanut protein isolate (PPI) was oxidized by peroxyl radicals derived from 2,2ʹ-azobis (2-amidinopropane) dihydrochloride (AAPH), and the emulsion properties stabilized by oxidized PPI were evaluated. During the storage, protein oxidation happened in the peanut beverage, accompanied by deteriorating their stability. Low storage temperature would lighten the oxidation extent and the peanut beverage instability. High roasting pretreatment of peanut kernels before making peanut beverage would enhance the protein oxidation. Emulsion stabilized by oxidized PPI had larger mean droplet size and lower surface charge. Microstructure of PPI stabilizing emulsion showed that emulsions stabilized by PPI of overoxidation underwent severe droplet aggregation during storage. Protein oxidation was an important factor influencing stability during peanut beverage storage.

Heat and light colour stability of beverages coloured with a natural carotene emulsion: Effect of synthetic versus natural water soluble antioxidants

Natural carotenoid emulsions are commonly used to colour beverages. However, carotenoids are frequently prone to oxidation, which results in undesirable colour loss. This study investigates the effect of the direct addition to the beverage of water soluble antioxidants on the colour stability in both direct light (sun test) and heat conditions. A synthetic antioxidant, ascorbic acid, is compared to a natural one, a rosemary extract rich in rosmarinic acid. The addition of ascorbic acid results in improved stability to light but has negative effect for heat stability. The addition of rosemary affects both heat and light stability favourably, even though it is not as efficient to prevent carotenoid degradation in the sun test. It can be concluded that the rosemary extract is a good natural alternative to synthetic ascorbic acid. Its combination with ascorbic acid could be very efficient to improve both light and heat stability of beverages coloured with natural carotenoids.

Chemical composition, antioxidant capacity and shelf life stability of blueberry and cranberry flavored maple sap water beverages (647.5)

Maple sap water is a by‐product of reverse osmosis filtration of maple sap during the production of maple syrup. The objective of this study was to develop blueberry and cranberry flavored beverages using maple sap water. The flavored sap water beverages were formulated using blueberry and cranberry concentrates, acidulant, and sugar and were pasteurized before bottling. Physicochemical characteristics, microbiological quality, ascorbic acid content, and antioxidant capacity of the beverages were analyzed during storage at 4 or 23 °C for 8 weeks. No growth of the total plate count, coliform, and yeast/mold in the beverages was seen initially, nor was it detected throughout the 8‐week storage either at 4 or 23 °C. The sugar content, pH, and titratable acidity for the flavored maple sap water beverages were significantly impacted by storage temperature, time and their interaction (P < 0.05). The storage temperature, time and their interaction significantly affected the area and peak of color absorption at 450 to 600 nm of flavored maple sap water beverages (P<0.01). The ascorbic acid content and total antioxidant capacity of flavored maple sap water beverages were significantly decreased during storage (P<0.01). Results showed that the maple sap water can be used for formulation of flavored functional beverage.

Comparing product stability of probiotic beverages using litchi juice treated by high hydrostatic pressure and heat as substrates

Abstract The aim of this study was to evaluate the use of litchi juice treated by high hydrostatic pressure (HHP) as substrates for producing a probiotic beverage by Lactobacillus casei . The quality attributes and product stability of fermented heat- and HHP-treated litchi juice by L. casei were compared. Compared with fermented heat-treated litchi juice, fermented HHP-treated litchi juice showed a better color, flavor and overall acceptance, and also retained more total phenolics and antioxidant capacity. Both viability counts of L. casei were more 8.0 log CFU/mL in heat- and HHP-treated litchi juice after 4 weeks of storage at 4 °C. Besides, some quality attributes in fermented heat- and HHP-treated litchi juice showed the tendency to slow decrease during storage at 4 °C, but both scores of overall acceptance of fermented heat- and HHP-treated litchi juice showed no reduction after the storage of 4 weeks at 4 °C. Overall, the application of HHP treatment could be an ideal alternative of heat treatment to ensure the microbial safety, consistent sensory and nutritional quality of fermented litchi juice prior to fermentation. Industrial relevance The study is relevant to fermentation of litchi juice by probiotic L. casei . In this study, results shown the application of high hydrostatic pressure (HHP) treatment could be an ideal alternative of heat treatment to ensure the microbial safety, consistent sensory and nutritional quality of fermented litchi juice prior to fermentation.

Degradation kinetics of rebaudioside A in various buffer solutions

Summary Rebaudioside A is a noncaloric high-intensity sweetener extracted from Stevia rebaudiana. For it to be used in foods, rebaudioside A needs to be stable during processing and storage. This study evaluated the kinetics of rebaudioside A degradation in 0.02 and 0.1 m citrate and phosphate buffer solutions at pH 3, 5 and 7 stored at 20, 30 and 40 °C for 9 months. At pH 3 and temperatures less than 30 °C, degradation was slow (i.e. less than 6% loss in 6 months) and not affected by buffer type or buffer concentration. At pH 7, the degradation of rebaudioside A increased dramatically in phosphate buffer (losses of up to 25% in 6 months at 30 °C), while remaining relatively slow in citrate buffer (less than 5% loss). The degradation rates at pH 7 increased 2.6 times as the concentration of phosphate buffer increased. For optimum stability of beverages containing rebaudioside A, formulations with lower concentrations of citrate buffer stored at lower temperatures are recommended.

Influence of Intermediate Maillard Reaction Products with Enediol Structure on the Oxidative Stability of Beverages

The influence of Maillard reaction products, originating from special malt, on the oxidative flavor stability of beverages was investigated by ESR methods (EAP determination, T500 values) and traditional methods according to MEBAK and Chapon to determine the reducing power or potential. Simultaneously, the color, SO2 content, and concentration of specific dicarbonyl compounds were determined (HPLC method). The aim of the study was to get a deeper insight into the antioxidative properties of wort and beer brewed with special malt and the influence of reductones/enediols as intermediate Maillard reaction products on the oxidative stability. The results show a direct correlation between the content of Maillard reaction products in malt and a higher reducing power or potential, if measured by Chapon or MEBAK method. In contrast to this, the same special malt leads to a higher radical generation in wort and the final beer (T500 values) and consequently to a lower oxidative stability (EAP value) measured by EPR spectroscopy. These contradictory results seem to be one reason why the influence of special malt on beer stability has been discussed controversially in literature. In further investigations, by addition of caramel color, malt extract, reductone solutions, and ascorbic acid to beer, it was possible to get more information on the properties of specific intermediate Maillard reaction products. The explanation of the described contradictory results arises from the strong reduction properties of Maillard reaction intermediate products with reductone/enediol structure. In analogy to the formation of reductones from fructose through 2,3-enediol and 1-deoxyosone, the formation of reductones from glucose is theoretically possible, in which 1,2-enediol is produced from glucosone catalyzed by the reduction of metal ions. These reductones/enediols can rapidly reduce oxidized metal ions like Fe+3 to Fe+2, resulting in an acceleration of oxygen activation (ROS, reactive oxygen species) and intensifying the Fenton/Haber-Weiss reaction system. Hence, a stronger radical generation of very reactive radicals (e.g., OH·) can be observed in the wort and beer matrix. The acceleration of the reaction system leads to a faster consumption of antioxidative substances, such as SO2, resulting in lower oxidative beer stability. Altogether, the results present the pro- and antioxidative effect of specific Maillard reaction intermediate products with reductone/enediol structure in beer and other beverages caused by the addition of special malts. Consequently, the use of special malts is a question of malt type and should be limited to the necessary addition for the adjustment of the desired color in the brewing process. Furthermore is the application of ascorbic acid addition, especially in combination with an SO2 addition, as an antioxidant component to improve the oxidative beer, to handle carefully.

Evaluation of Antioxidant Activity on Flavor Stability of Beer and Beer-Like Beverages

The relationships among flavor stability, antioxidant activity, and aging-related indices of beer were examined in traditional all-malt and adjunct beer, Happoshu (a beer-like beverage with less than 67% malt content), and New-genre (a beer-like beverage without malt, or Happoshu diluted with spirit) beverages. Flavor stability was evaluated by assessing flavor-staling degree using sensory analysis after an accelerated storage test at 30°C. Hydroxyl radical, the most reactive oxygen species, is considered a major determinant for flavor stability of beer. However, the staling degree measure exhibited a more significant correlation with 1,1′-diphenyl-2-picrylhydrazyl (DPPH)-scavenging activity than the hydroxyl radical-scavenging activity. The lag time of the hydroxyl radical generation analyzed by electron spin resonance spectroscopy is now used as an index of flavor stability of beer; it is thought that longer lag times indicate higher antioxidant activity of beer. However, a markedly longer lag time was observed in Happoshu and New-genre than in beer, although Happoshu and New-genre showed lower antioxidant activities than beer. Lag time did not appear to be applicable as an index of flavor stability for Happoshu and New-genre. DPPH-scavenging activity was found to be a more suitable and a common index for assessing flavor stability in not only traditional all-malt and adjunct beers but also Happoshu and New-genre, depending mostly on polyphenol-mediated antioxidant activity. In a brewing fermentation test, changes in DPPH-scavenging activity during fermentation were not observed, which suggests that the antioxidant activity of casting wort could be critical to the flavor stability of not only beer but also beer-like beverages.

Evaluation of long-term stability of milk beverages by a novel method for rapid determination of aggregation forces between colloidal particles

Long-term stability of milk-based emulsions in canned coffee or tea varies with the formulation of small-molecule emulsifiers aiming at bacteriostatic effects or stability-enhancing effects. To predict the long-term stability of the emulsions in short-time period, we developed a novel method for rapid determination of aggregation forces between colloidal particles using model emulsions and suspensions with different stability to aggregation for the first step. The novel method was based on an idea that particles with stronger aggregation forces tend to form aggregates and cannot be readily redispersed. While the milk-based emulsions were subjected to long-term storage test with coffee extract, the same emulsions, but not including coffee extract, were rapidly evaluated by both the novel method and a common method, Turbiscan analysis often applied to the evaluation of emulsion stability. Statistical regression analysis according to the datasets obtained by the two rapid assays revealed that the long-term stability of the milk-based emulsions can be better predicted by the aggregation forces evaluated by the newly developed method than the initial aggregating process evaluated by Turbiscan method. We named the novel method “vibration-redispersion method”.

Factors Influencing the Antioxidant and Pro-Oxidant Activity of Polyphenols in Oil-in-Water Emulsions

The nonenzymatic oxidation of polyphenols bearing di- and trihydroxyphenol groups results in the generation of hydrogen peroxide (H₂O₂), a reactive oxygen species that can potentially compromise the oxidative stability of foods and beverages. An investigation of the factors that promote the oxidation of a model polyphenol, (-)-epigallocatechin-3-gallate (EGCG), was undertaken in a model lipid-based food system. Factors affecting oxidative stability, such as exogenous iron chelators (ethylenediaminetetraacetic acid; EDTA and 2,2-bipyridine; BPY) and pH (3 and 7) were evaluated in hexadecane and flaxseed oil-in-water (o/w) emulsions. At neutral pH, H₂O₂ levels were observed to rise rapidly in hexadecane emulsions except for EDTA-containing treatments. However, EDTA-containing samples showed the highest rate of EGCG oxidation, suggesting that H₂O₂ was rapidly reduced to hydroxyl radicals (HO•). Conversely, at pH 3, H₂O₂ concentrations were lower across all treatments. EDTA conferred the highest degree of EGCG stability, with no loss of the catechin over the course of the study. In order to assess whether or not the H₂O₂ production seen in oxidatively stable hexadecane emulsions translated to pro-oxidant activity in an oxidatively labile food lipid system, the effect of EGCG on the stability of flaxseed o/w emulsions was studied. EGCG displayed antioxidant activity at pH 7 throughout the study; however at pH 3, pro-oxidant activity was seen in EGCG-containing emulsions, with and without BPY. This study attempts to provide a mechanistic understanding of the conditions wherein polyphenols simultaneously exert pro-oxidant and antioxidant behavior in lipid dispersions.

The influence of different combinations of probiotic bacteria and fermentation temperatures on the microbiological and physicochemical characteristics of fermented lactic beverages containing soybean hydrosoluble extract during refrigerated storage

Lactic beverages containing probiotics were prepared with whole UHT milk, whey of Mozzarella cheese, soybean hydrosoluble extract and sugar. Three formulations were studied, each one containing a different combination of probiotic/starter bacteria, fermented at two different temperatures (37 and 45 °C). The aim of this work was to verify the influence of these variables on the viability of probiotic microorganisms and on the physicochemical stability of lactic beverages during storage under refrigeration (21 days at 7 °C). The results indicated that the fermentation temperature had a significant effect on the viability of probiotic bacteria. Counts for Lactobacillus acidophilus were affected by storage time, resulting appropriate after 21 days only for the beverage fermented at 37 °C. Physicochemical parameters did not exhibit drastic variations - proving the stability of formulations during storage. Cells of Bifidobacterium spp. showed high survival ability, probably due to the presence of growth promoters from soybean and cheese whey. The fermentation temperature of 37 °C allowed counts above the minimum limit for all the studied microorganisms, being preferred to the temperature of 45 °C. The inclusion of soybean hydrosoluble extract, a prebiotics source, resulted in a symbiotic product with more benefits to the health of consumers.

Microbial and enzymatic stability of fruit juice-milk beverages treated by high intensity pulsed electric fields or heat during refrigerated storage

The influence of high intensity pulsed electric fields (HIPEF) treatment (35 kV/cm, bipolar 4 μs square wave pulses at 200 Hz) on the inactivation of Listeria innocua in fruit juice–whole (FJ–WM) or skim milk (FJ–SM) beverages was assessed. As well, the effects of HIPEF or conventional thermal (90 °C 60 s) processing in terms of microbial and enzymatic stability and changes on physicochemical parameters of the beverages during refrigerated storage were also studied. HIPEF and thermal processing ensured the microbial stability of the beverages during 56 days at 4 °C without significant changes on pH, acidity and soluble solid content values. Thermal processing was more effective than HIPEF in reducing Pectin Methyl Esterase (PME) activity in FJ–SM and FJ–WM beverages since its activity was reduced by 70.66% and 87.33%, respectively. With regards to Polygalacturonase (PG), HIPEF treatment reduced by 26.92% and 20.93% the enzyme activity in the FJ–WM and FJ–SM beverages, respectively, whereas thermal treatment did not inactivate PG in both beverages. HIPEF or thermally-treated samples showed higher viscosity than the untreated ones, being this increment more pronounced in the beverages with whole milk. Therefore, HIPEF processing may be a feasible technology in order to obtain shelf stable and fresh-like fruit juice-milk beverages.

A Comparison of the Stability of Beverage Cloud Emulsions Formulated with Different Gum Acacia‐ and Starch‐Based Emulsifiers

The performance of several hydrocolloids (3 gum acacias, 1 modified gum acacia, and 3 modified starches) in stabilizing beverage emulsions and corresponding model beverages was investigated employing different core materials, emulsifier usage levels, and storage temperatures. Concentrated emulsions were prepared using orange terpenes or Miglyol 812 (comprising medium-chain triglycerides, MCT) weighted 1:1 with ester gum, stored at 25 or 35 degrees C, and analyzed on days 0, 1, and 3. On day 3, model beverages were made from each emulsion, stored at both temperatures, and analyzed weekly for 4 wk. Stability of concentrated emulsions was assessed by measuring mean particle size and by visual observations of ringing; beverage stability was judged similarly and also by loss of turbidity. Particle size measurements showed concentrated emulsions containing gum acacia or modified gum acacia with either core material were stable over 3 d storage at both temperatures whereas those made with modified starches were not, destabilization being faster at 35 degrees C. Beverages based on orange terpenes, in contrast to Miglyol, yielded smaller mean particle sizes, both on manufacture and during storage, regardless of hydrocolloid used. Visual observations of ringing generally supported this finding. Modified gum acacia was evaluated at both recommended and higher usage levels, stability increasing in the latter case. In general, all gum acacia and modified gum acacia emulsifiers were superior in stability to those based on modified starches, at either temperature, for orange terpene-based beverages. In Miglyol-based beverages, similar results were seen, except 1 modified starch performed as well as the gum acacia products.

Electrochemically deposited boronate affinity extracting phase for covalent solid phase microextraction of cis-diol biomolecules

A new format of solid phase microextraction (SPME), boronate affinity SPME, was proposed for the first time for covalent extraction of cis-diol containing biomolecules. This new SPME format is based on the reversible complex formation between boronic acids and 1,2- and 1,3-cis-diols. The complex formation and dissociation can be facilely controlled by changing pH. An extracting phase of poly-3-aminophenylboronate (polyAPBA) electrochemically deposited on a metal wire was employed to demonstrate the concept of this new methodology. Catechol and riboflavin were used as the test analytes, and the SPME extraction was combined off-line with high-performance liquid chromatographic (HPLC) separation followed by UV absorbance or fluorescence detection. Fundamental aspects, such as selectivity, extraction/desorption equilibrium, linearity, effect of competing compounds, reproducibility and life-time, were first investigated. Then the developed method was applied to beer samples since the content of riboflavin plays an important role in the flavor stability of beverages. Excellent performance of the SPME fibers was observed for both standard and real samples. Particularly, the expected excellent features of the polyAPBA extracting phase were experimentally verified, which include specific selectivity, eliminated matrix effect and manipulable capture/release. The new methodology of SPME can be a promising tool since a lot of 1,2- and 1,3-cis-diol-containing compounds are of great biological importance.

Flavor Stability of Alternative Malt-based Beverages

In recent years the market share for alternative malt-based beverages has grown as consumers look for alternative, new, and refreshing products. To date, however, no information has been gathered about the flavor stability of such beverages. In this work, stale flavor compounds in commercial and pilot-scale malt-based beverages were analyzed and compared with appropriate sensory results. The study showed that the aging of flavored malt-based beverages can be described by changes in the contents of 3-methylbutanal, 2-furfural, benzaldehyde, phenylacetaldehyde, hexadienal, heptanal, methional, and beta-damascenone, with an index increase from 4.097 �mol/L in fresh samples to 4.899 �mol/L in aged samples. The aging indicator value determined for novel malt-based beverages was confirmed in pilot-scale lactic acid-fermented beverages. In unfermented malt beers, the aging process can be described by the sum of the Strecker aldehydes 2- and 3-methylbutanal and phenylacetaldehyde and the thermal indicator methylfurfural. During simulated aging, an increase of 181 nmol/L was observed.

Laccases and Their Applications: A Patent Review

Laccases are an interesting group of multi copper enzymes, which have received much attention of researchers in last decades due to their ability to oxidize both phenolic and non-phenolic lignin related compounds as well as highly recalcitrant environmental pollutants. This makes these biocatalysts very useful for their application in several biotechnological processes. Such applications include the detoxification of industrial effluents, mostly from the paper and pulp, textile and petrochemical industries, polymer synthesis, bioremediation of contaminated soils, wine and beverage stabilization. Laccases are also used as catalysts for the manufacture of anti-cancer drugs and even as ingredients in cosmetics. Recently, the utility of laccases has also been applied to nanobiotechnology. This paper reviews recent and important patents related to the properties, heterologous production, molecular cloning, and applications of laccases within different industrial fields as well as their potential extension to the nanobiotechnology area.

電子線照射によるシュガービートおよびシトラスペクチンの機能特性変化

Changes in functional properties of pectin extracted from sugar beet or citrus peel by electron beam in solid state or aqueous solution were investigated. Citrus pectin (CP) was degraded at both solid state and aqueous solution by irradiation with electron beam. Sugar beet pectin (SBP) was degraded at solid state but in aqueous solution at high concentrate was polymerized by irradiation with electron beam. SBP polymerized by electron beam formed hydrogel.This hydrophilic polymer was useful as water absorbent. Moreover, it was confirmed that the emulsification stability and acidified milk beverage stabilization of SBP was enhanced by electron beam.