Chemical composition and sensory analysis of cheese whey-based beverages using kefir grains as starter culture

The aim of the present work was to evaluate the use of the kefir grains as a starter culture for tradicional milk kefir beverage and for cheese whey-based beverages production. Fermentation was performed by inoculating kefir grains in milk (ML), cheese whey (CW) and deproteinised cheese whey (DCW). Erlenmeyers containing kefir grains and different substrates were statically incubated for 72 h at 25 °C. Lactose, ethanol, lactic acid, acetic acid, acetaldehyde, ethyl acetate, isoamyl alcohol, isobutanol, 1-propanol, isopentyl alcohol and 1-hexanol were identified and quantified by high-performance liquid chromatography and GC-FID. The results showed that kefir grains were able to utilise lactose in 60 h from ML and 72 h from CW and DCW and produce similar amounts of ethanol (∼12 g L−1), lactic acid (∼6 g L−1) and acetic acid (∼1.5 g L−1) to those obtained during milk fermentation. Based on the chemical characteristics and acceptance in the sensory analysis, the kefir grains showed potential to be used for developing cheese whey-based beverages.The authors acknowledge the financial support from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), CAPES-GRICES and Lactogal for supplying CW powder

Comparative study of the biochemical changes and volatile compound formations during the production of novel whey-based kefir beverages and traditional milk kefir

Cheese whey (CW) and deproteinised cheese whey (DCW) were investigated for their suitability as novel substrates for the production of kefir-like beverages. Lactose consumption, ethanol production, as well as organic acids and volatile compounds formation, were determined during CW and DCW fermentation by kefir grains and compared with values obtained during the production of traditional milk kefir. The results showed that kefir grains were able to utilise lactose from CW and DCW and produce similar amounts of ethanol (7.8–8.3 g/l), lactic acid (5.0 g/l) and acetic acid (0.7 g/l) to those obtained during milk fermentation. In addition, the concentration of higher alcohols (2-methyl-1-butanol, 3-methyl-1-butanol, 1-hexanol, 2-methyl-1-propanol, and 1-propanol), ester (ethyl acetate) and aldehyde (acetaldehyde) in cheese whey-based kefir and milk kefir beverages were also produced in similar amounts. Cheese whey and deproteinised cheese whey may therefore serve as substrates for the production of kefir-like beverages similar to milk kefir.The authors acknowledge the financial support from Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES), CAPES-GRICES and Lactogal for supplying cheese whey powder

Production, chemical characterization, and sensory profile of a novel spirit elaborated from spent coffee ground

This study describes a process for the production of a spirit from spent coffee ground (SCG), the chemical composition, and sensory profile of this distillate. The process consisted in three steps starting with the extraction of aroma compounds by hydrothermal treatment of SCG, followed by the fermentation of this extract supplemented with sucrose to ethanol, and the fermented broth distillation. Seventeen volatile compounds were identified in the distillate (including alcohols, esters, aldehydes, and acids), all of them in concentrations able to promote pleasant characteristics to the product. Based on the chemical composition, \SCG\ spirit was considered as having organoleptic quality acceptable for human consumption. Twelve descriptors defined the sensory characteristics of this product, including clarity and brilliance (visual analysis), coffee, roasted, alcohol, elegance and frankly (olfactory analysis), bitter, astringent and pungent (gustatory analysis), and finesse (olfactory and gustatory analyses). Coffee was the most representative aroma by olfactory analysis. Based on the sensory analysis, \SCG\ spirit was considered as having features of a pleasant beverage, with smell and taste of coffee

Taking ethanol quality beyond fuel grade: A review

Ethanol production in the United States approached 15 billion gal/year in 2015. Only about 2.5% of this was food‐grade alcohol, but this represents a higher‐value product than fuels or other uses. The ethanol production process includes corn milling, cooking, saccharification, fermentation, and separation by distillation. Volatile byproducts are produced during the fermentation of starch. These include other alcohols, aldehydes, ketones, fatty acids and esters. Food‐grade ethanol is generally produced by wet milling, where starch and sugars are separated from the other corn components, resulting in much smaller concentrations of the impurities than are obtained from fermentation of dry‐milled corn, where cyclic and heterocyclic compounds are produced from lignin in the corn hull. Some of these volatile byproducts are likely to show up in the distillate and these fermentation byproducts in ethanol could cause unpleasant flavours and affect human health if used for human consumption. There is some interest in improving ethanol quality, since human consumption represents a higher value. Advanced purification techniques, such as ozone oxidation, currently used for drinking water and municipal wastewater treatment, offer possibilities for adaptation in ethanol quality improvement. The development of analytical techniques has enabled the detection of low‐concentration compounds and simple quality assurance of food‐grade alcohol. This review includes the most recent ethanol production methods, potential ethanol purification techniques and analytical techniques. Application of such techniques would aid in the development of simplified alcohol production

Chemical fingerprints of Raki a traditional distilled alcoholic beverage

Fourteen brands of commercial Raki samples were analysed chemically and compared with two samples produced in a local distillery, according to traditional methods, to determine whether the raw materials (grape or raisin) and distillation practices result in distinguishable chemical fingerprints in the final product. The samples were analysed with respect to the content of trans‐anethol, methyl alcohol, ethyl alcohol, higher alcohols and other volatiles, using gas chromatography. Principal component analysis showed that chemometric analysis could be used to distinguish between traditional and flavoured Raki product

Production and characterization of a novel distilled alcoholic beverage produced from blueberry ( Vaccinium corymbosum

Introduction. The cultivation of underutilized berries and the process production of high-value-added products, such as fruit-based spirits, could have a beneficial effect on the economy of disadvantaged rural mountain areas of Spain. However, production of a distilled alcoholic beverage from the blueberry has not been reported before. Materials and methods. The pulp of blueberries var. Bluecrop was fermented with Saccharomyces cerevisiae IFI83, distilled by using a steam drag distillation system and the volatile compounds were determined by gas chromatography. Results and discussion. In the distillate obtained, the mean concentrations of ethanol (45.3 mL 100 mL-1 distillate), volatile substances (317.1 g hL-1 absolute alcohol) and methanol (261.0 g hL-1 absolute alcohol) were in accordance with the specifications that the European Council (Regulation 110/2008) fixed for these compounds. In addition, the ratios [3-methyl-1-butanol/2-methyl-1-propanol] and [2-methyl-1-propanol/1-propanol] were 2.60 and 1.34, respectively, indicating that the distilled alcoholic beverage has a good organoleptic quality. Conclusion. The results suggest that blueberry can be successfully used for the production of a novel spirit with a good sensory quality that is safe for the consumers