Selecting autochthonous lactic acid bacteria for co-inoculation in Chinese bayberry wine production: Stress response, starter cultures application and volatilomic study.

This study focused on isolating and characterising autochthonous lactic acid bacteria (LAB) from spontaneously fermented Chinese bayberry (CB) and their potential application in CB wine fermentation in co-inoculation with yeast starter cultures. Numerous LAB, including Lactiplantibacillus (Lp.) plantarum (9), Limosilactobacillus (Lb.) fermentum (6), Lactococcus (Lc.) lactis (3), Enterococcus (Ec.) hirae (1), Leuconostoc (Le.) mesenteroides (1), and Weissella (Ws.) cibaria (1), were isolated and identified. The isolated strains Lp. plantarum ZFM710 and ZFM715, together with Lb. fermentum ZFM720 and ZFM722, adapted well to unfavourable fermentation environment, including ethanol, osmolality, and acidity stresses, were selected for producing CB wine by co-inoculation with Saccharomyces cerevisiae. During fermentation, the presence of LAB promoted the development of S. cerevisiae, while the population dynamics of LAB in different groups at different stages showed strain-specific differences. Fermentation trials involving LAB yielded a lower ethanol concentration except for Lp. plantarum ZFM715. Compared to the pure S. cerevisiae fermented sample, the addition of LAB led to a clear modulation in organic acid composition. Lb. fermentum strains in co-fermentation led to significant decreases in each classified group of aroma compounds, while Lp. plantarum ZFM715 significantly increased the complexity and intensity of aroma compounds, as well as the intensities of fruity and floral notes. The study selects interesting strains for the design of starter cultures for use in CB wine production, underlining the interest in the selection of autochthonous LAB in fruit wines, with the aim of improving the adaptation of bacteria to specific environmental conditions and shaping the unique traits of the finished products.

Composition of Sugars, Organic Acids, Phenolic Compounds, and Volatile Organic Compounds in Lingonberries (Vaccinium vitis-idaea L.) at Five Ripening Stages.

Wild lingonberries are a traditional source of food in the Nordic countries and an important contributor to economic activity of non-wood forest products in the region. Lingonberries are a rich source of bioactive compounds and can be a valuable contributor to a healthy diet. However, there are few studies available on how the bioactive compounds in lingonberries develop as they ripen. In this investigation, we examined the content of 27 phenolic compounds, three sugars, four organic acids, and 71 volatile organic compounds at five ripening stages. The study showed that, while the highest content of phenolic compounds was found early in the development, the organoleptic quality of the fruits improved as they ripened. From the first to the last stage of development, anthocyanins went from being nearly absent to 100 mg/100 g fw, and there was an increased content of sugars from 2.7 to 7.2 g/100 g fw, whereas the content of organic acids decreased from 4.9 to 2.7 g/100 g fw, and there were several changes in the profile of volatiles. The contents of flavonols, cinnamic acid derivatives, flavan-3-ols, and the total concentration of phenolic compounds were significantly lower in the fully ripe berries compared to berries in the early green stage. In addition to the changes occurring due to ripening, there was observed variation in the profile of both phenolic compounds and volatiles, depending on the growth location of the berries. The present data are useful for the assessment of harvest time to obtain the desired quality of lingonberries.

Ultrasonication-assisted enzymatic bioprocessing as a green method for valorizing oat hulls.

Ultrasonication-assisted enzymatic treatments using Viscozyme®, Alcalase®, and feruloyl esterase were applied to recover proteins, avenanthramides, phenolic acids, free sugars, and organic acids from oat hulls (OH). The profiles of the chemical compounds in OH were markedly influenced by the nature of enzymes, ultrasonication frequency, and processing time. A significant increase in the contents of proteins and phenolic acids was observed in the liquid fraction of all enzymatic treatments, which was 2-19 folds higher than those detected in untreated OH. In contrast, avenanthramides were mostly degraded during enzyme hydrolyses. The highest content of proteins (68.9 g/100 g DM) was found in the liquid fraction after the feruloyl esterase treatment assisted with 90 min of ultrasonication at 25 kHz. This fraction also contained 0.07% phenolic acids, 14.1% free sugars, and 1.8% organic acids, which can be potentially used as the ingredient of novel food products.

The Stability of Phenolic Compounds in Fruit, Berry, and Vegetable Purees Based on Accelerated Shelf-Life Testing Methodology.

Evaluating the stability of polyphenols in fruit, berry, and vegetable purees helps to assess the quality of these products during storage. This study aimed to (1) monitor the stability of total phenolic content (TPC) in four-grain puree with banana and blueberry (FGBB), mango-carrot-sea buckthorn puree (MCB), and fruit and yogurt puree with biscuit (FYB); (2) study the effect of aluminum-layered vs. aluminum-free packaging on the changes in TPC; and (3) assess the suitability of accelerated shelf-life testing (ASLT) methodology to evaluate the stability of polyphenols. The samples were stored at 23 °C for 182, 274, 365, and 427 days. The corresponding time points during ASLT at 40 °C were 28, 42, 56, and 66 days, calculated using Q10 = 3. The TPC was determined with Folin-Ciocalteu method. The results revealed that the biggest decrease in TPC took place with high-pH FGBB, which contained fewer ingredients with bioactive compounds. Minor changes were seen in FYB and MCB, which had lower pH values, and contained a larger amount of ingredients that include polyphenols. In addition, the choice of packaging material did not affect the TPC decrease in each puree. Finally, it was concluded that the ASLT methodology is suitable for studying the TPC changes in such purees, but the corresponding Q10 factors may vary and should be determined based on the chemical profile and ingredient list of the product.

Exploring the Sensory Properties and Preferences of Fruit Wines Based on an Online Survey and Partial Projective Mapping.

Non-grapefruits with unique sensory properties and potential health benefits provide added value to fruit wine production. This study aimed to explore consumers' fruit wine preferences and descriptors for the varied fruit wines. First, 234 consumers participated in an online survey concerning their preferences for different wines (grape, blueberry, hawthorn, goji, Rosa roxburghii, and apricot). In addition, their attitudes towards general health interests, food neophobia, alcoholic drinks, and sweetness were collected. Grape wine and blueberry wine were the most favored wines, and goji wine was the least liked fruit wine sample. Moreover, 89 consumers were invited to evaluate 10 commercial fruit wines by using partial projective mapping based on appearance, aroma, and flavor (including taste and mouthfeel) to obtain a comprehensive sensory characterization. Multifactor analysis results showed that consumers could differentiate the fruit wines. Participants preferred fruit wines with "sweet", "sour", and "balanced fragrance", whereas "bitter", "astringent", "deep appearance", and "medicinal fragrance" were not preferred. Attitudes toward health, food neophobia, alcohol, and sweetness had less influence than taste and aroma (sensory attributes) on the preferences for fruit wine products. More frequent self-reported wine usage resulted in higher consumption frequency and liking ratings compared to non-users. Overall, the main factors influencing consumer preference for fruit wines were the sensory characteristics of the products, especially the taste.

Comparison of phenolic composition and sensory quality among pear beverages made using Saccharomyces cerevisiae and Torulaspora delbrueckii.

The effects of Saccharomyces cerevisiae and Torulaspora delbrueckii on phenolic composition and sensory quality were characterized in the production of alcoholic beverages from selected pear cultivars with diverse biochemical characteristics. The fermentation process generally affected the phenolic composition by increasing the contents of hydroxycinnamic acids and flavan-3-ols and reducing the levels of hydroxybenzoic acids, procyanidins, and flavonols. Although the phenolic compositions and sensory properties of pear beverages depended primarily on pear cultivar selection, the applied yeast strains also played important roles in beverage quality. Fermentation with T. delbrueckii resulted in higher caffeoylquinic acid and quercetin-3-O-glucoside contents, higher rated intensities of 'cooked pear' and 'floral' odors and a sweeter taste than fermentation with S. cerevisiae. Moreover, higher concentrations of hydroxybenzoic acids, hydroxycinnamic acids, and flavonols correlated closely with astringency perception. Applying T. delbrueckii strains and breeding novel pear cultivars are important approaches to produce fermented beverages of high quality.

Aroma characteristics of volatile compounds brought by variations in microbes in winemaking.

Wine is a highly complex mixture of components with different chemical natures. These components largely define wine's appearance, aroma, taste, and mouthfeel properties. Among them, aroma is among the most important indicators of wine's sensory characteristics. The essence of winemaking ecosystem is the process of metabolic activities of diverse microbes including yeasts, lactic acid bacteria, and molds, which result in wines with complicated and diversified aromas. A better understanding of how these microbes affect wine's aroma is a crucial step to producing premium quality wine. This study illustrates existing knowledge on the diversity and classification of wine aroma compounds and their microbial origin. Their contributions to wine characteristics are discussed, as well. Furthermore, we review the relationship between these microbes and wine aroma characteristics. This review broadens the discussion of wine aroma compounds to include more modern microbiological concepts, and it provides relevant background and suggests new directions for future research.

Effects of fermentation and enzymatic treatment on phenolic compounds and soluble proteins in oil press cakes of canola (Brassica napus).

To develop novel processes for valorizing agro-industry side-streams, canola (Brassica napus) oil press cakes (CPC) were treated with lactic acid bacteria, carbohydrase, and protease. Altogether 29 protein-rich liquid fractions were obtained, of which the composition was analyzed using chromatographic and mass spectrometric methods. A clear association was revealed between the treatments and phenolic profile. Applying certain lactic acid bacteria enhanced the release of sinapic acid, sinapine, glycosylated kaempferols, and other phenolic compounds from CPC. Co-treatment using protease and Lactiplantibacillus plantarum was effective in degrading these compounds. The fraction obtained after 16 h of hydrolysis (with Protamex® of 2% dosage) and 48 h of fermentation (using L. plantarum) contained the lowest phenolic content (0.2 g/100 g DM) and a medium level of soluble proteins (78 g/100 g) among all samples studied. The fractions rich in soluble proteins and low in phenolics are potential food ingredients with improved bioavailability and sensory properties.

Baltic herring (Clupea harengus membras) protein isolate produced using the pH-shift process and its application in food models.

In this study, protein isolate was prepared from Baltic herring (Clupea harengus membras) using alkaline pH-shift process. The aim of this research was to characterize the protein isolate and to study its potential in food models. A special focus was placed on characterization of odour profile and volatile compounds contributing to the odour profile of the protein isolate using gas chromatography - olfactometry. 2,3-Pentanedione, hexanal, 4(Z)-heptenal, 2,4(E,E)-nonadienal, and three compounds tentatively identified as 1,5(E)-octadien-3-ol, 1,5(Z)-octadien-3-ol, and 1,5(Z)-octadien-3-one were the most important odour-contributing compounds in the protein isolate (Nasal Impact Factor 83-100%, intensity 2.6-3.3 on a scale 0-4). 2-Methylpropanal, 2- and 3-methylbutanal, and three unknown compounds were less intense in the protein isolate than in the raw material, which might have contributed to the lower intensity of fishiness observed for the protein isolate (2.2 vs 3.3 on a scale 0-4). Surimi-type gels prepared from the Baltic herring protein isolate had texture properties (hardness and cohesiveness) similar to those of commercial products. Due to the abundancy of dark muscle tissue in Baltic herring, the protein isolate had a significantly lower whiteness (W = 63) compared to the commercial surimi products (W = 80-83). Increasing the solubilisation or precipitation pH did not improve the whiteness, but resulted in significantly softer, less cohesive, and less chewy gels. The findings of this study indicate that alkaline-based pH-shift processing is a potential way to increase the food application of Baltic herring.

Food Fortification Using Spray-Dried Emulsions of Fish Oil Produced with Maltodextrin, Plant and Whey Proteins-Effect on Sensory Perception, Volatiles and Storage Stability.

Fortification of foods with fish oil rich in n-3 fatty acids improves the nutritional value, but creates challenges with flavor and oxidative stability, especially during storage. Pea, soy, and sunflower proteins were used in combination with whey protein or maltodextrin to encapsulate fish oil by spray-drying. The use of whey protein compared with maltodextrin as wall material improved oxidative stability of spray-dried emulsions, although the use of whey protein increased the number of observed cracks in outer shell of the particles. Non- and encapsulated oil were used in cookies and chocolates to examine flavor characteristics by generic descriptive analysis and volatile products by solid-phase microextraction with gas chromatography-mass spectrometry. A long-term storage test at room temperature was conducted to evaluate the oxidative stability of the food models. Fortification changed the texture, odor, and flavor of the food models with fishy flavor being the most impactful attribute. For both food models, use of pea protein with maltodextrin resembled attributes of control the best. Fortification and encapsulation material also affected volatile profiles of food models. Both non-encapsulated oil and whey protein formulations performed well in regard to oxidative stability for both food models. Generally, the cookie model showed more potential for fortification than the chocolate one.

Chemical Composition of Juices Made from Cultivars and Breeding Selections of European Pear (Pyrus communis L.).

The phenolic profiles and other major metabolites in juices made from fruits of 17 cultivars and selections of European pears were investigated using UHPLC-DAD-ESI-QTOF-MS and GC-FID, respectively. A total of 39 phenolic compounds were detected, including hydroxybenzoic acids, hydroxycinnamic acids, flavan-3-ols, procyanidins, flavonols, and arbutin. Among these compounds, 5-O-caffeoylquinic acid was the most predominant, accounting for 14-39% of total quantified phenolic contents (TPA) determined in this study. The variations were mainly cultivar dependent. The genetic background effect on the chemical compositions is complex, and breeding selections from the same parental cultivars varied dramatically in chemical compositions. Putative perry pears contained more 4-O-caffeoylquinic acid, 5-O-caffeoylquinic acid, caffeoyl N-trytophan, caffeoylshikimic acid, coumaroylquinic acid isomer, syringic acid hexoside, procyanidin dimer B2, (+)-catechin, and malic acid, whereas putative dessert pears had higher esters, alcohols, and aldehydes. The results will be helpful in providing industry with phytochemical compositional information, assisting pear selections in commercial utilization.

Impact of enzymatic pre-treatment on composition of nutrients and phytochemicals of canola (Brassica napus) oil press residues.

The study aimed to develop a biorefining process to recover proteins and dietary fibres from a food industry side-stream, canola (Brassica napus) oil pressing residues. The materials were treated with commercial protease, carbohydrase, and phytase to obtain protein-rich supernatants and fibre-rich precipitates. The compositions of these fractions were analyzed using LC-MS (glucosinolates and phenolics) and GC-MS (sugars, acids, and amino acids). Compared to raw material, the supernatants were richer in proteins, sugars, acids, amino acids, phenolic acids, and flavonols; the precipitates had higher levels of minerals and dietary fibres. The enzymatic treatment decreased the contents of phytic acid, glucosinolates, and phenolic alkaloids in all fractions. The applied enzymes effectively enhanced solubility of proteins, despite the lower yield of crude proteins compared to the alkaline extraction (40-82 vs 91 g/100 g dry matters). The impact of enzymes on other chemical components was also revealed by using principal component analysis.

Use of Non-Saccharomyces Yeasts in Berry Wine Production: Inspiration from Their Applications in Winemaking.

Although berries (nongrape) are rich in health-promoting bioactive compounds, and their consumption is associated with a lower risk of diverse chronic diseases, only a fraction of the annual yield of berries is exploited and consumed. Development of berry wines presents an approach to increase the utilization of berries. Alcoholic fermentation is a complex process driven by yeasts, which influence key properties of wine diversification and quality. In winemaking, non-Saccharomyces yeasts were traditionally considered as undesired microorganisms because of their high production of metabolites with negative connotations. However, there has been a recent and growing interest in the application of non-Saccharomyces yeast in many innovative wineries. Numerous studies have demonstrated the potential of these yeasts to improve properties of wine as an alternative or complement to Saccharomyces cerevisiae. The broad use of non-Saccharomyces yeasts in winemaking provides a promising picture of these unconventional yeasts in berry wine production, which can be considered as a novel biotechnological approach for creating value-added berry products for the global market. This review provides an overview of the current use of non-Saccharomyces yeasts in winemaking and their applicative perspective in berry wine production.

Sensory and chemical characterization of Chinese bog bilberry wines using Check-all-that-apply method and GC-Quadrupole-MS and GC-Orbitrap-MS analyses.

The sensory and chemical profiles of commercial bog bilberry (BB) wines were investigated using a multi-analytical approach. Sensory test included scaling and check-all-that-apply (CATA) method with questions on liking of BB wine. The sensory data was correlated with their volatile compound profiles determined using gas chromatography coupled with quadrupole and orbitrap mass spectrometry (GC-Quadrupole/Orbitrap-MS). In general, all BB wines were characterized with "fruity", "blueberry" and "floral" odors and "sour", "mouth puckering" and "sweet" flavors. Samples more frequently characterized as "fruity" and "floral" in CATA were preferred by the panelists (n = 93). High relative proportions of o-cymene, p-cymenene, 1-octen-3-one and 3-ethylphenol in a sample (described as "ginger" and "chili") resulted in a lower liking rating. Similarly, generally disliked sample described with "Chinese herbs" and "licorice" was characterized by compounds 3-methylpentan-1-ol, 1,1,6-trimethyl-1,2-dihydronaphthalene, and 4-vinylphenol. The data will give novel information for berry wine and beverage industry on the quality factors of BB wines linked to higher acceptance.

Effect of oat or rice flour on pulse-induced gastrointestinal symptoms and breath hydrogen in subjects sensitive to pulses and controls - a randomised cross-over trial with two parallel groups.

Pulses are healthy and sustainable but induce gut symptoms in people with a sensitive gut. Oats, on the contrary, have no fermentable oligo- di-, monosaccharides and polyols compounds and are known for the health effects of their fibres. This 4-day cross-over trial investigated the effects of oat and rice flour ingested with pulses on gut symptoms and exhaled gases (4th day only) in subjects with a sensitive gut or IBS (n 21) and controls (n 21). The sensitive group perceived more symptoms after both meals than controls (P = 0·001, P = 0·001). Frequency, intensity or quality of the symptoms did not differ between meals during the first 3 d in either group. More breath hydrogen was produced after an oat than rice containing meal in both groups (AUC, P = 0·001, P = 0·001). No between-group difference was seen in breath gases. During day 4, both sensitive and control groups perceived more symptoms after the oat flour meal (P = 0·001, P = 0·0104, respectively) as mainly mild flatulence. No difference in moderate or severe symptoms was detected. Increased hydrogen production correlated to a higher amount of perceived flatulence after the oat flour meal in both the sensitive and the control groups (P = 0·042, P = 0·003, respectively). In summary, ingestion of oat flour with pulses increases breath hydrogen levels compared with rice flour, but gastrointestinal symptoms of subjects sensitive to pulses were not explained by breath hydrogen levels. Additionally, consumer mindsets towards pulse consumption and pulse-related gut symptoms were assessed by an online survey, which implied that perceived gut symptoms hinder the use of pulses in sensitive subjects.

Comparison of volatile compounds and sensory profiles of alcoholic black currant (Ribes nigrum) beverages produced with Saccharomyces, Torulaspora, and Metschnikowia yeasts.

Black currants (Ribes nigrum) were fermented with Saccharomyces and non-Saccharomyces yeasts without added sugar to yield low-ethanol-content beverages. The effects of yeasts on the volatile compounds and sensory characteristics were analysed by HS-SPME-GC-MS, GC-O, and generic descriptive analysis. Ninety-eight volatile compounds were identified from the black currant juice and fermented beverages. Significant increases in the contents of esters (131 %), higher alcohols (391 %), and fatty acids (not present in juice sample) compared to initial juice were observed depending on the yeasts used. GC-O analysis revealed the higher impact of esters on the sensory properties of Saccharomyces bayanus-fermented beverage compared to the Torulaspora delbrueckii-fermented beverage. In the sensory evaluation, non-Saccharomyces yeasts resulted in a higher 'black currant odour'. However, all beverages were intensely sour, which can be a significant challenge in the development of alcoholic berry beverages.

Phenolic compound profiles in Finnish apple (Malus × domestica Borkh.) juices and ciders fermented with Saccharomyces cerevisiae and Schizosaccharomyces pombe strains.

The phenolic compounds in juices and ciders made with Saccharomyces cerevisiae or Schizosaccharomyces pombe from eleven Finnish apple cultivars were analyzed using liquid chromatographic and mass spectrometric methods combined with multivariate data analysis. In general, the ciders contained less phenolic compounds than corresponding apple juices. In the studied apple juices and ciders, hydroxycinnamic acids were the most predominant, accounting for around 80% of total phenolic compounds. Apple juices contained more flavonol glycosides and dihydrochalcones whereas cider processing resulted in increased amount of free hydroxycinnamic acids. The contents of individual phenolic compounds were more dependent on the apple cultivars than the yeast species. Certain cultivars contained remarkably higher contents of dihydrochalcones and hydroxycinnamic acids when comparing with other cultivars. Ciders made using S. pombe remained higher contents of procyanidins and (+)-catechin while S. cerevisiae ciders contained higher individual hydroxycinnamic acids, such as 5-O-caffeoylquinic acid, 4-O-caffeoylquinic acid, 3-O-p-coumaroylquinic acid, and 4-O-p-coumaroylquinic acid.

Red beet (Beta vulgaris) betalains and grape (Vitis vinifera) anthocyanins as colorants in white currant juice - Effect of storage on degradation kinetics, color stability and sensory properties.

Red beet betalains, grape anthocyanins, and their mixtures were used as colorants in white currant juice. Storage stability of the compounds was evaluated using liquid chromatography and the degradation kinetic order and parameters were calculated. Degradation of betalains followed first-order kinetics, while the degradation of anthocyanins did not have any trend toward any order kinetics. The coexisting anthocyanins and their concentration affected the rate constant of betalains. Betalains degraded faster than anthocyanins, their mixtures promoted respective degradation. Pyruvate derivatives of anthocyanins showed better stability. During storage, all samples became more yellowish with CIELab method and lighter in color. In the projective mapping sensory test, samples were distinguished by the colorant type as the main criteria and the storage time as the second criteria. Anthocyanin (described as 'dark' and 'natural') was preferred by sensory panelists over betalain (described as 'pink' and 'unnatural'), as were the fresh samples over stored samples.

Impact of lactic acid fermentation on sensory and chemical quality of dairy analogues prepared from lupine (Lupinus angustifolius L.) seeds.

Lupine (Lupinus sp.) is a valuable source of plant proteins. There is little knowledge on the impact of food processing on composition and sensory properties of lupine products. In this research, we investigated the impact of fermentation with five starters of lactic acid bacteria on the sensory quality and flavor-active compounds in dairy analogues prepared from sweet lupine (Lupinus angustifolius L.). The sensory qualities of unfermented and fermented products were studied with generic descriptive analysis and affective tests. Acids and sugars were analyzed with GC-FID and volatiles with HS-SPME-GC-MS and GC-O. Fermentation increased sourness and 'vinegar' odor and reduced the 'beany' odor and flavor as well as the unpleasantness of flavor. Formation of volatiles during the fermentation was dependent on the starters. However, all fermentations increased the contents of lactic, acetic, and hexanoic acids, while reducing the contents of hexanal, described as 'grassy' in the unfermented lupine sample.

Effect of Saccharomyces cerevisiae and Schizosaccharomyces pombe strains on chemical composition and sensory quality of ciders made from Finnish apple cultivars.

Composition of volatile compounds and concentrations of sugars and organic acids were studied in apple ciders produced with Saccharomyces cerevisiae and Schizosaccharomyces pombe yeasts using eleven different Finnish apple cultivars. Moreover, sensory quality of selected ciders was studied using check-all-that-apply test with untrained panelists. Seventy-seven volatile compounds were detected in the samples using HS-SPME-GC-MS. In general, the ciders had higher concentrations of higher alcohols, aldehydes, and acetals whereas the juices contained higher contents of C6-alcohols. Simultaneously, fermentation using S. pombe resulted in lower concentrations of malic acid, ethyl pentanoate, ethyl hexanoate, and volatile acids and higher concentrations of residual sugars compared to S. cerevisiae. Ciders made using S. cerevisiae were characterized as 'alcoholic' and 'yeasty' while S. pombe ciders were more frequently described as 'sweet', 'honey-like', and less rated as sour. Besides the strong effect by the yeasts, apple cultivars had significant effects on the compositional and sensorial properties of apple ciders.