Novel Low-Alcohol Sangria-Type Wine Products with Immobilized Kefir Cultures and Essential Oils

Abstract

Low-alcohol wines (ranging from <0.5 to 10.5% vol) are novel products that have been steadily gaining scientific and commercial attention. Over the past few years, consumer interest in healthier foods has augmented the development of novel functional products containing probiotic microorganisms, while the urge for a reduction in chemical preservatives has shifted the food and wine industry’s interest to natural alternatives, such as essential oils (EOs). In the present study, low-alcohol (~6% vol) wines with (wet or dried) immobilized kefir cultures on fruit pieces, and essential oils (Citrus medica or Cinnamomum zeylanicum) were produced and evaluated for their properties. The viability of the immobilized kefir cultures on apple and pear pieces was not affected by the addition of EOs, and levels >7 logcfu/g were maintained after 2 h of immersion in wines. HS-SPME GC/MS analysis revealed characteristic compounds originating from the chemical composition of the added EOs in the final products. Principal component analysis (PCA) revealed that the relative content of terpenes, alcohols and carbonyl compounds played a major role in the discrimination of low-alcohol wine products. EO addition affected the products’ sensory evaluation and resulted in significantly higher aroma and taste density compared to control samples. Notably, all novel Sangria-type wine variants were approved during preliminary sensory evaluation.