Inclusion of curcumin in b-cyclodextrin: a promising prospective as food ingredient.

In the present work, the inclusion complexes between curcumin (CC) and ß-cyclodextrin (ß-CD) were obtained through co-precipitation at different times of magnetic stirring and simple mixing. The stoichiometric ratio between CC and ß-CD was ascertained to be 1:2. The samples prepared by co-precipitation (24 h magnetic stirring and 24 h cold static precipitation) and by simple mixing, showed the best performance in terms of powder recovery (72 and 97%, respectively), encapsulation efficiency (72 and 95%, respectively) and tinting power, while no significant differences were revealed in terms of loading capacity (about 14%). Using either inclusion method, the complexation of CC into ß-CD make the colorant 20-fold more water soluble than pure CC. The pigment stability was also enhanced under different storage conditions (high temperature and light exposure), either when applied in liquid or gel state. However, after 30 days under natural light exposure, an appreciable colour change from yellow to orange was revealed to an extent probably perceptible by an inexperienced observer.

Heat and light stability of natural yellow colourants in model beverage systems.

The performance of 10 natural yellow colourants at different concentrations (0.001-0.3% w/v) was investigated in a model beverage system at various pH levels (3.5, 5.5 and 7.5) containing 10% w/v of sucrose, with or without ethanol (15% v/v) to simulate both alcoholic and non-alcoholic lemon-like beverages. Thus, the incidence of pH, ethanol and colourant concentration on spectral properties as well as turbidity were evaluated. The λmax was found to be independent from concentration in the tested range (0.001- 0.3% w/v), whereas the specific absorbance at λmax increased linearly. Moreover, the absorption spectrum and λmax of yellow pigments were found to be independent of pH and ethanol. Gardenia, safflower, and curcumin had the highest colour intensity and the lowest turbidity level. Heat and light stability were studied for these as well. Safflower was found to be the most stable colourant against heat (25, 40, 60, 80°C) and light (550 W/m2, 30°C).

Yeast cells in double layer calcium alginate-chitosan microcapsules for sparkling wine production.

This paper focuses on the use of a new type of yeast encapsulation procedure, applying the chitosan-calcium alginate double layer microcapsules, for the production of Riesling sparkling wine. Four different sparkling wines were produced by free or encapsulated yeasts. The four types of yeast used were adapted (Free EtOH-A, Encapsulated EtOH-A) and non-adapted to ethanol (Free, Encapsulated). The different yeast-inoculating formats had a significant impact on oxygen consumption and pressure increase rate in the bottle during the prise de mousse. Similarly to the free form, encapsulated yeast successfully completed the secondary fermentation. After an ageing period of 6 months, volatiles and sensory profiles of sparkling wines were compared. Although, some differences in volatile profiles were found among samples, sparkling wines produced by Encapsulated EtOH-A showed sensory properties, in terms of aroma, taste and body, similar to those produced by free yeast (both adapted and non-adapted to ethanol).

Pre-fermentative cold maceration in presence of non-Saccharomyces strains: Evolution of chromatic characteristics of Sangiovese red wine elaborated by sequential inoculation.

Two different Metschnikowia strains (M. pulcherrima MP 346 or M. fructicola MF 98-3) were applied for the first time, during pre-fermentative cold maceration (PCM) in order to enhance the properties and stability of Sangiovese wine color. During the 2014 and 2015 vintages a total of eight wines were produced with 24 h of cold maceration (PCM 24 h) or 72 h (PCM 72 h), respectively. PCM was carried out in presence of MP 346 or MF 98-3 or pectic enzyme (Cuvée Rouge). The sequential inoculation of S. cerevisiae strain was carried out at the end of PCM. After 12 months in the bottle, the MP 346 and MF 98-3 wines contained much higher levels of total flavonoids than the Control sample for both vintages and regardless PCM duration. Moreover, in both vintages only MF 98-3 showed a higher color intensity than the Control sample after 12 months in the bottle. However, neither PCM duration nor the microbial/enzymatic treatment increased the level of anthocyanins at draining off. Both wines produced by the pre-fermentative inoculum with Metschnikowia strains (MP 346 and MF 98-3) retained their red hue, regardless the duration of pre-fermentative and fermentative macerations, while the Control wines were characterized by faster rates of color loss.

Characterization of Active Dry Wine Yeast During Starter Culture (Pied de Cuve) Preparation for Sparkling Wine Production.

The preparation of yeast starter culture (Pied de Cuve) for producing sparkling wine with the traditional method is a key factor for manufacturing a good Prise de mousse. In this paper, the evolution of total yeast population, its viability during Pied de Cuve preparation, and the pressure profile during the 2nd fermentation in 2 different base wines made from Bombino bianco and Chardonnay grapes were investigated using 4 different commercial active dried yeasts. The study proves that despite the initial differences observed throughout the acclimatization phase, all the tested strains showed similar results on either the total population (from 8.2 × 10(7) cells/mL to 1.3 × 10(8) cells/mL) or cellular viability (from 70% to 84%). Independently from the base wine tested, the kinetic of sugar consumption was faster during the gradual acclimatization to the alcoholic medium (phase II) and slower during the preparation of starter culture in active growth phase (phase III). During both of these phases Saccharomyces cerevisiae bayanus Vitilevure DV10(®) (Station œnotechnique de Champagne) proved to have a higher sugar consumption rate than the other strains. During the Prise de mousse, S. cerevisiae bayanus Lalvin EC-1118(®) (Lallemand) reached the maximum pressure increase within time in both base wines.

Assessing the Potential Content of Ethyl Carbamate in White, Red, and Rosé Wines as a Key Factor for Pursuing Urea Degradation by Purified Acid Urease.

The ethyl carbamate (EC) content of a wine after a given temperature-time storage was theoretically predicted from the potential concentration of ethyl carbamate (PEC), as determined via an accelerated EC formation test. Such information was used to decide whether an enzymatic treatment was needed to reduce the wine urea level before bottling/aging. To this end, 6 white, red, and rosé wines, manufactured in Italy as such or enriched with urea, were tested for their PEC content either before or after enzymatic treatment using a purified acid urease preparation derived from Lactobacillus fermentum. The treatment was severely affected by the total phenolic content (TP) of the wine, the estimated pseudo-first-order kinetic rate constant for NH3 formation reducing by a factor of approximately 2000 as the TP increased from 0 to 1.64 g L(-1) . Such a sensitivity to TP was by far greater than that pertaining to a killed cell-based enzyme preparation used previously. Urea hydrolysis was successful at reducing EC concentration in wines with low levels of TP and other EC precursors.