Applicability of Saccharomyces cerevisiae Strains for the Production of Fruit Wines Using Cocoa Honey Complemented with Cocoa Pulp

Research background. Cocoa honey (CH) and cocoa pulp (CP) are both fruit pulps highly appreciated but, until now, CH is less processed than CP. In this work, it was investigated the applicability of strains of S. cerevisiae to ferment CH complemented with CP, to obtain fruit wines and improve CH commercialization. Experimental approach. The selection of a strain, previously isolated from cachaçaria distilleries in Brazil, took place based on its fermentation performance. The conditions for fermentation with S. cerevisiae L63 were then studied in relation to: volumetric proportion (φCH) of CH (complemented with CP), sucrose addition (γsuc), temperature (T) and inoculum size (No). The best conditions were applied in order to obtain fermentation profiles. Results and conclusions. S. cerevisiae L63 (No=107–108 cell/mL) is capable to ferment φCH of 90 and 80 % (V/V) for 24 or 48 h with γsuc of 50 and 100 g/L at T=28–30 °C resulting in wines with ethanol contents from 8 to 14 % (V/V). Additionally, the φCH=90 % (V/V) wine resulted in the lowest residual sugar concentration (<35 g/L) than the φCH=80 % (V/V) wine (~79 g/L) which could be classified as a sweet wine. In general, S. cerevisiae L63 resulted in a similar fermentation performance than a commercial strain tested, indicating its potential for fruit pulp fermentation. Novelty and scientific contribution. Therefore, S. cerevisiae L63 is capable to ferment CH complemented with CP to produce fruit wines with good commercial potentials that may also benefit small cocoa producers by presenting a product with greater added value.

Vinegar Production from Corinthian Currants Finishing Side-Stream: Development and Comparison of Methods Based on Immobilized Acetic Acid Bacteria

Fruit wastes and side-streams can be used for vinegar production to create added value for the agri-food sector and enhance farmer incomes and local economies. In this study, methods for vinegar production by wild and selected acetic acid bacteria (the quick starter Acetobacter aceti and the acid-resistant Komagataeibacter europaeus), free (FC) and immobilized (IC) on a natural cellulosic carrier, are proposed using sweet wine made from the industrial finishing side-stream (FSS) of Corinthian currants as raw material. The results showed all cultures can produce vinegar with 46.65 ± 5.43 g/L acidity, from sweet FSS wine containing 5.08 ± 1.19% alcohol. The effect of immobilization was more obvious in the case of the selected culture, presenting better acetification efficiency, both fresh and after cold storage for 2 months. The vinegars had an antioxidant capacity of 263.5 ± 8.4 and 277.1 ± 6.7 mg/L (as ascorbic acid) and phenolic content 333.1 ± 12.0 and 222.2 ± 2.9 mg/L (as gallic acid) (for FC and IC, respectively). They also had a rich volatilome (140 compounds identified by SPME GC-MS), with higher percentages of esters identified in vinegars made by IC. The results are encouraging for vinegar production with IC of a mixed A. aceti and K. europaeus culture.

“Wine, sweet wine”: significados e determinantes da compra por impulso de vinho do Porto

Este estudo tem como objetivo identificar os significados atribuídos pelos portugueses ao vinho do Porto; além disso, investigar, através de um estudo experimental, como a unicidade e o desconto influenciam a tendência para comprar por impulso o vinho do Porto, e perceber como as variáveis em estudo influenciam cada um dos contextos experimentais. Participaram no estudo 538 portugueses (382 mulheres e 156 homens, idade média = 33,35 anos). Os resultados indicaram que, quando os portugueses pensam no vinho do Porto, eles pensam no processo, no armazenamento e nos locais associados à produção do vinho; pensam nas suas características, nas ocasiões sociais especiais onde é usualmente consumido e no seu valor cultural. Com o estudo experimental, verificou-se que, aquando da exposição a um produto único, os portugueses tendem a comprar mais por impulso, independentemente do preço. Enquanto, no caso de um vinho mais popular, o desconto é um fator determinante na tendência para comprar por impulso. Adicionalmente, os resultados também mostraram que o desconto, as emoções positivas, a unicidade do vinho e a impulsividade do consumidor também foram fatores que influenciaram a tendência para comprar vinho do Porto por impulso.

Effects of Light Exposure, Bottle Colour and Storage Temperature on the Quality of Malvasia delle Lipari Sweet Wine

The influence of light exposure, bottle color and storage temperature on the quality parameters of Malvasia delle Lipari (MdL) sweet wine were investigated. Wine samples bottled in clear-colored (colorless, green and amber) glass were stored under different artificial lighting conditions, in order to simulate the retail environment (one cool-white, fluorescent lamp) and to perform an accelerated test (four and six cool-white, fluorescent lamps). The storage temperature was kept constant (25 °C) for the first 90 days of the experiment and then samples were monitored for up to 180 days at higher temperatures (30, 35 and 40 °C). The principal enological parameters, total phenols, color, 5-hydroxymethylfurfural (HMF) and 2-furaldehyde (2F) contents were studied. The shelf-life test pointed out minimum variations of the basic chemical parameters, while the quality attributes most affected by lighting were color, together with HMF and 2F levels which, hence, can be considered as indicators of the severity of storage conditions.

Investigation of Volatile Compounds, Microbial Succession, and Their Relation During Spontaneous Fermentation of Petit Manseng

Petit Manseng is widely used for fermenting sweet wine and is popular among younger consumers because of its sweet taste and attractive flavor. To understand the mechanisms underlying spontaneous fermentation of Petit Manseng sweet wine in Xinjiang, the dynamic changes in the microbial population and volatile compounds were investigated through high-throughput sequencing (HTS) and headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) technology, respectively. Moreover, the relationship between the microbial population and volatile compounds was deduced via multivariate data analysis. Candida and Mortierella were dominant genera in Petit Manseng wine during spontaneous fermentation. Many fermentative aroma compounds, including ethyl octanoate, isoamyl acetate, ethyl butyrate, ethyl decanoate, isoamyl alcohol, ethyl laurate, isopropyl acetate, hexanoic acid, and octanoic acid, were noted and found to be responsible for the strong fruity and fatty aroma of Petit Manseng sweet wine. Multivariate data analysis indicated that the predominant microorganisms contributed to the formation of these fermentative aroma compounds. Hannaella and Neomicrosphaeropsis displayed a significantly positive correlation with the 6-methylhept-5-en-2-one produced. The current results provide a reference for producing Petit Manseng sweet wine with desirable characteristics.

Comparative Analysis Regarding the Chemical and Microbiological Characteristics of Some Red Wine Assortments Produced in Two Romanian Viticultural Areas

Sweet, semi-dry and semi-sweet red wine samples from two vine-growing regions in Romania: Vrancea and Recas were analyzed aiming to show their main chemical properties including heavy metal content, and, microbiological characteristics. The chemical analysis showed that the semi-dry wine (W1) has a high polyphenol content, permanganate index and content of Fe, Zn and Cu, but the lowest content of anthocyanins, sugar and Mn; the total acidity of semi-sweet wine W3 was the highest, while the semi-sweet wine W2 contained the highest concentrations of anthocyanins and SO2. No contamination with yeasts, molds and bacteria was found when opening the wine bottles, these colonies having grown one month after opening. The importance of this article comes from the comprehensive presentation of the connections among the physicochemical and microbiological characteristics of sweet to semi-sweet red wines, or to semi-dry from two vine-growing regions in Romania: Vrancea and Recas.

An overview on botrytized wines

Noble rot wine is a specific type of sweet wine that derives from the infection of grape berries by a fungus called Botrytis cinerea. These wines are produced in specific wine regions around the world, with Sauternes region of France and Tokay region of Hungary being the most famous ones. The purpose of the current article is to provide a systematic review on the different stages of botrytized wines production, including a detailed analysis of the technical aspects involved. Specifically, it describes the process and development of berry infection by B. cinerea, and special emphasis is given to the main stages and operations of winemaking, conservation, aging and stabilization. A complex combination of a number of parameters (e.g., very specific environmental conditions) explains the rarity of noble rot occurrence and highlights the uniqueness of botrytized wines.