Model Beverage System Research Articles

Inhibition Effect of Mace Extract Microemulsion on Vitamin C Photooxidation in Aqueous Systems

Photooxidation in food systems cause nutritional losses and produces undesirable flavor, toxic and color compounds, which make foods less acceptable or unacceptable to consumers. The objective of this research was to know the effectiveness of mace extract microemulsion to inhibit vitamin C photooxidation in aqueous systems. Aqueous food systems used are both beverage model system and apple juice beverage, where in each system enriched by 100 ppm vitamin C as substrate and 20 ppm erytrosin as photosensitiser. It is about one percent and two percent of microemulsion that contain mace extract of 0, 500 and 750 ppm were added into each of aqueous food system. Inhibition effect of mace extract microemulsion toward vitamin C photooxidation based on the rate of vitamin C degradation in aqueous food systems that illuminated by fluorescent light with 2000 lux intensity within eight hours. The result indicated the mace extract microemulsion has anti-photooxidation activity and ability to inhibit vitamin C photooxidation in aqueous systems.

Antimicrobial delivery systems based on electrostatic complexes of cationic ɛ-polylysine and anionic gum arabic

ɛ-Polylysine (ɛ-PL) is a potent food-grade cationic antimicrobial but its application within foods and beverages is currently limited because of its tendency to associate with anionic substances, thereby increasing product turbidity or forming sediments. In this study, we examined a potential means of overcoming these problems by forming electrostatic complexes between cationic ɛ-PL and anionic gum arabic (GA). The nature of the complexes formed depended on the mass ratio of gum arabic-to-ɛ-PL (RGA–PL), since this determined their electrical charge, aggregation stability, and antimicrobial efficacy. The electrical charge on the complexes went from positive to negative with increasing RGA–PL, with the point of zero charge being around RGA–PL ∼15. Soluble complexes were formed at low and high RGA–PL levels, but insoluble complexes were formed at intermediate levels (i.e. 5 < RGA–PL < 25). The antimicrobial activities of the ɛ-PL–GA complexes were investigated in a model beverage system against two acid resistant spoilage yeasts: Zygosaccharomyces bailii (ZB) and Saccharomyces cerevisiae (SC). In general, the antimicrobial efficacy of ɛ-PL decreased with increasing amount of GA, and this effect also depended on microorganism type, with SC being less sensitive to increased levels of gum arabic than ZB. Finally, we showed that certain ɛ-PL–GA complexes (15 μg/mL ɛ-PL; RGA–PL ≥ 20) could be incorporated into model beverages without adversely affecting their appearance or physical stability. This work has shown that the function of a cationic antimicrobial (ɛ-polylysine) can be improved by incorporating it within electrostatic complexes using a food-grade anionic biopolymer (gum arabic).

Photo- and Thermodegradation of Anthocyanins from Grape and Purple Sweet Potato in Model Beverage Systems

Recently, interest in the application of natural pigments to replace synthetic dyes in beverages has grown. The present study investigates the stability of anthocyanin-rich grape and purple sweet potato (PSP) extracts to photo- and thermostresses in ready-to-drink (RTD) beverage models including hot fill beverages with various concentrations of ascorbic acid, a preserved beverage, and a vitamin-enriched water beverage. Thermo- and photostresses were induced at 40, 60, and 80 °C and 250, 500, and 750 W/m(2), respectively. Qualitative and quantitative data on anthocyanin content were collected by pH differential assay and LC-MS. Increasing concentration of ascorbic acid caused more rapid degradation through thermostress, but had a protective effect through photostress. Additionally, PSP was significantly less stable than grape extract in the vitamin-enriched water model beverage through photostress. Furthermore, photostress caused the formation of monoacylated peonidins from diacylated peonidins.

Application of Proanthocyanidins from Peanut Skins as a Natural Yeast Inhibitory Agent

Proanthocyanidins were extracted from peanut skins and investigated for their antimicrobial activity against Saccharomyces cerevisiae, Zygosaccharomyces bailii, and Zygosaccharomyces bisporus in traditional growth media (Sabouraud Dextrose and Maltose broth) and a simulated apple juice beverage. Peanut skins extracts (PSE) were prepared through a multisolvent extraction procedure. The PSE extended the lag phase growth of the 3 yeasts studied at a concentration of 1 mg/mL and at 10 mg/mL yeast growth was totally inhibited for 120 h. PSE was fractionated by normal phase high performance liquid chromatography and the active components/fractions were determined. Compounds present in the fractions were identified by liquid chromatography-mass spectrometry to determine the compounds responsible for inhibition. Fractions consisting mostly of A-type proanthocyanidin dimers, trimers, and tetramers showed the highest percent inhibition toward the yeasts tested in this study. Both optical density (OD) and standard enumeration plating methods were performed in this study. The OD method led to an overestimation of the inhibitory effects of PSE, the 2 methods agreed in respect to treatment effects but not the severity of the inhibition. There is a growing consumer demand for "fresh like" products containing reduced amounts of chemical preservatives without compromising food safety and quality. Therefore, the goal of this study was to determine if an extract of peanut skins containing flavonoid rich compounds could function as a natural antimicrobial in a model beverage system. Proteins were removed through the process of producing the peanut skin extract, thus it is unlikely to contain peanut allergens. The antimicrobial compounds mentioned in this study were successfully integrated into a model beverage system, and were found to have antimicrobial effect. However, the incorporation of these compounds would likely lead to negative sensory attributes at the concentration needed to achieve an appreciable antimicrobial effect alone.

Colour properties, stability, and free radical scavenging activity of jambolan (Syzygium cumini) fruit anthocyanins in a beverage model system: Natural and copigmented anthocyanins

The colour and stability properties of jambolan anthocyanins, both natural and copigmented forms, were investigated in beverage model as well as their radical scavenging ability. Natural anthocyanins of jambolan revealed low colour intensity due to glycosylation structure of the anthocyanins as diglucoside. The intermolecular copigmentation of anthocyanins with sinapic acid, caffeic acid, ferulic acid, and rosemary polyphenolic extract could enhance the colour intensity, which was observed through spectrometric parameters, such as hyperchromic effect (ΔAvis-max) and bathochromic shift (Δλvis-max). In addition of sinapic acid, caffeic acid, and rosemary polyphenolics also increased the stability of the anthocyanin colour during exposure to white fluorescent light and storage at refrigeration and room temperatures, whereas on high thermal treatments, this phenomenon was not observed. Furthermore, beverage model coloured with natural or copigmented anthocyanins revealed DPPH radical-scavenging activity. The AEAC values indicated that the beverage models with copigmented anthocyanins had higher scavenging activity than the beverage with natural anthocyanins.

Optimization of Gum Combination in Prebiotic Instant Hot Chocolate Beverage Model System in Terms of Rheological Aspect: Mixture Design Approach

Mixture design was used to investigate the effects of four different gums (xanthan gum, guar gum, alginate and locust bean gum) and their combinations on the rheological properties of a prebiotic model instant hot chocolate beverage (including 3.5% inulin) and to determine their interactions in the model beverage. Simplex centroid mixture design was applied to predict the physicochemical (soluble solids, pH, colour properties) and rheological parameters (consistency index (K), flow behaviour index (n) and apparent viscosity (η50)) of the samples. In the model, the optimum gum combination was found by simplex centroid mixture design as 59% xanthan gum and 41% locust bean gum, and the highest K value was 33.56 Pa sn. The increase of guar gum and alginate in the gum mixture caused a decrease in the K value of the sample.

Photostability study of natural high-potency sweetener monatin in a model beverage system and characterisation of the degradation products

Photodegradation of the naturally occurring high-potency sweetener monatin was studied in a lemon–lime beverage model system under simulated conditions. Most of the monatin disappeared after treatment with the equivalent of four days of ultraviolet light exposure and resulted in the formation of a number of degradation products. These degradation products have been isolated and characterised in the present study. On the basis of these identified structures, a photodegradation pathway has been proposed suggesting that monatin gets oxidised on the indole C-2 position to result in 2-hydroxymonatin. It also undergoes decarboxylation resulting in a 4-oxopentanoic acid analog and a major rearrangement resulting in an isonicotinic acid analog. Monatin also degrades into 3-formylindole and indole-3-carboxylic acid. Besides these, a partial monatin dimer and a monatin lactone were identified as additional degradation products. Details of the isolation and characterisation are given.

Taste–aroma interactions in a citrus flavoured model beverage system: Similarities and differences between acid and sugar type

A model citrus flavoured beverage was created to investigate the effect of varying levels of sugars and acids on flavour and taste perception. Two naturally occurring sugars; glucose and fructose, and two organic acids; citric and lactic acid, were studied using D-optimal design spaces created using experimental design software (Design Exp). Perception was studied using the scaling technique of magnitude estimation by a panel of trained assessors. Alterations in aroma volatile release profiles and viscosity were measured instrumentally using APCI-MS and rheometry, respectively. Aroma release profiles were unaffected by varying tastant levels and only the highest level of glucose (150 g/l) resulted in a small increase in viscosity. However, flavour perception was increased on addition of tastants, although, interestingly, glucose showed a different profile to fructose despite equi-sweet levels being used. This data provides evidence for taste–aroma interactions within this citrus flavoured system which are not due to physico-chemical interactions within the beverage matrix. This study has also uncovered apparent differences between effects of fructose and glucose on flavour perception, again not due to alterations in physical factors, and raises the intriguing possibility of different receptors/receptor mechanisms between the two monosaccharides.

Colour stability of anthocyanins from Isabel grapes ( Vitis labrusca L.) in model systems

The influence of temperature, pH, the presence or absence of light, the presence or absence of oxygen and the presence or absence of tannic acid on the colour stability of anthocyanins from crude extract of Isabel grapes ( Vitis labrusca L.) in food and model systems was studied. The spectrophotometric results (Δ λ, Δ A) revealed interaction between the anthocyanins of the crude extract and tannic acid, suggesting copigmentation. In a model system, temperature, pH, the presence or absence of light, the presence or absence of oxygen and the presence or absence of tannic acid, significantly affected the half-life time of anthocyanins. The long half-time of the anthocyanins from Isabel grapes in a yoghurt model system indicates that these pigments are relatively stable in this food. In a rehydrated beverage model system at 4±1 °C, the presence of tannic acid (1:1, w/v) increased the half-life time by 187 h compared to the control samples.

Phytochemical composition and pigment stability of Açai (Euterpe oleracea Mart.).

Anthocyanin and polyphenolic compounds present in açai (Euterpe oleracea Mart.) were determined and their respective contribution to the overall antioxidant capacity established. Color stability of açai anthocyanins against hydrogen peroxide (0 and 30 mmol/L) over a range of temperatures (10-30 degrees C) was also determined and compared to common anthocyanin sources. Additionally, stability in a model beverage system was evaluated in the presence of ascorbic acid and naturally occurring polyphenolic cofactors. Cyanidin 3-glucoside (1040 mg/L) was the predominant anthocyanin in açai and correlated to antioxidant content, while 16 other polyphenolics were detected from 4 to 212 mg/L. Red grape anthocyanins were most stable in the presence of hydrogen peroxide, while açai and pigments rich in acylated anthocyanins displayed lower color stability in a temperature-dependent manner. In the presence of ascorbic acid, acylated anthocyanin sources generally had increased color stability. Açai was recognized for its functional properties for use in food and nutraceutical products.

Effect of Storage on the Stability of Water Soluble Annatto Dye Formulation in a Simulated Orange-RTS Beverage Model System

Annatto ( Bixa orellana L.) seeds are the source of an orange yellow pigment. The water-soluble annatto dye formulations can be used in beverages, bakery and other food products. An annatto water-soluble dye formulation containing norbixin fraction 22.4 g/L was used in making an orange-ready-to-serve (RTS) beverage model with citric acid and sugar. The orange-RTS beverage was stored at ambient and refrigerated conditions in transparent as well as amber-coloured glass bottles for a period of 5 mo. A dilute solution of the annatto dye formulation (working stock) without addition of citric acid and sugar was also stored under similar conditions. The annatto water-soluble dye formulation and the orange-RTS beverage stored at refrigerated conditions stored well, whereas the losses were very high for the working stock of the formulation irrespective of the storage period/method.

Effect of Storage on the Stability of Water Soluble Annatto Dye Formulation in a Simulated Orange-RTS Beverage Model System

Annatto ( Bixa orellana L.) seeds are the source of an orange yellow pigment. The water-soluble annatto dye formulations can be used in beverages, bakery and other food products. An annatto water-soluble dye formulation containing norbixin fraction 22.4 g/L was used in making an orange-ready-to-serve (RTS) beverage model with citric acid and sugar. The orange-RTS beverage was stored at ambient and refrigerated conditions in transparent as well as amber-coloured glass bottles for a period of 5 mo. A dilute solution of the annatto dye formulation (working stock) without addition of citric acid and sugar was also stored under similar conditions. The annatto water-soluble dye formulation and the orange-RTS beverage stored at refrigerated conditions stored well, whereas the losses were very high for the working stock of the formulation irrespective of the storage period/method.

Time‐Intensity Parameters of Selected Carbohydrate and High Potency Sweeteners

ABSTRACTTime‐intensity (TI) sweetness curves were generated and ten TI parameters were determined for selected carbohydrate and high potency sweeteners. Samples were evalutated by trained panelists at 5% sucrose equivalency (SEV) in water for sucralose, sucrose, fructose, aspartame, cyclamate, acesulfame‐K and saccharin and at 9% SEV in water and a buffered model beverage system for sucralose, sucrose, fructose, aspartame and cyclamate. When compared within each system, differences in temporal properties appeared to be concentration and media dependent. No differences in onset characteristics were observed among equisweet groups. Aftertaste characteristics differed among sweeteners only .at 9% SEV in water where high potency sweeteners tended to have somewhat longer aftertaste than nutritive sweeteners.

Sweetness Adaptation of Some Carbohydrate and High Potency Sweeteners

ABSTRACTA sip‐and‐swallow procedure designed to provide stimulation resembling normal drinking was employed to investigate adaptation to sweetness and sourness over time in a model beverage system. Intensity judgements were made using magnitude estimation. Adaptation to sweeteners (sucrose, HFCS, sucralose and aspartame) alone and in blends was evaluated. Different degrees of sweetness adaptation were observed. Sucrose and HFCS displayed less adaptation than the high potency sweeteners, sucralose and aspartame. Blends containing two high potency sweeteners adapted to a greater degree than the individual components. Blends containing a carbohydrate and a high potency sweetener showed less adaptation than those containing two high intensity sweeteners. Sourness adaptation was not demonstrated.