Effect Of Fermentation Temperature Research Articles

Influence of Temperature-Controlled Fermentation on the Quality of Mild Coffee (Coffea arabica L.) Cultivated at Different Elevations

Controlled fermentation processes have high potential for improving coffee quality. The effect of fermentation temperature on beverage quality was investigated with coffee cultivated at elevations between 1166 and 1928 m. A completely randomized design was carried out at five elevation ranges at 200 m intervals in five farms per elevation range, and two temperatures (15 °C and 30 °C), which were maintained in a temperature-controlled bioreactor. Each temperature-controlled fermentation batch had a spontaneous fermentation batch (control treatment). Microbial identification of LAB and yeast was performed using a Biolog™ MicroStation™ ID System, and cup quality tests were performed following the SCA protocol. Tests conducted at 15 °C showed higher microbial community activity on the substrates used, indicating greater transformation potential than those conducted at 30 °C or those of spontaneous fermentation. According to Wilcoxon and Kruskal–Wallis tests, temperature-controlled fermentation resulted in high-quality coffee for all elevation ranges, with coffee from higher elevations and processed at controlled temperatures of 15 °C receiving the highest cup scores compared to coffee that was subjected to 30 °C. These results suggest that controlled temperature can be used to design standardized fermentation processes in order to enhance coffee quality through differentiated sensory profiles.

Effect of fermentation temperature on oenological parameters and volatile compounds in wine

The increase in temperature caused by climate change is one of the greatest challenges the wine industry has to face. Temperature increase affects sugar and alcohol content, which directly impact the chemical and organoleptic characteristics of wine. This has a serious impact on the competitiveness and profits of companies in the sector. Among the most studied strategies focused on guaranteeing wine quality is the use of yeast strains that are better adapted to the conditions generated by climate change. Therefore, this study seeks to evaluate whether the Saccharomyces cerevisiae strains LALVIN CY3079 and UVAFERM WAM maintain their organoleptic characteristics at different temperatures. For this purpose, 3 experimental fermentations were carried out at 16, 20, and 27ºC, respectively. Alcoholic fermentation was monitored (pH, sugars, and microbial population) and general oenological parameters (acetic, citric, malic, succinic, lactic, amine nitrogen, ammonium, and glycerol) were evaluated at the beginning and end of fermentation. In addition, the ethanol content and volatile compounds formed at the end of fermentation were analysed. As a result of these experimental fermentations, it was observed that most of the basic oenological parameters and volatile compounds are modified as a function of fermentation temperature.

Impact of Sugar Type Addition and Fermentation Temperature on Pomegranate Alcoholic Beverage Production and Characteristics.

The present study focuses on the production of pomegranate alcoholic beverage (PAB) from juice of the Wonderful variety. The effect of fermentation temperature (15 and 25 °C) and type of sugar added (adjustment to 20 °Brix) on the physicochemical characteristics, bioactive compounds, and volatile composition were studied. Sucrose, concentrated pomegranate juice, concentrated grape juice, and honey were used to increase the initial sugar content. The produced PABs contained ethanol in concentrations ranging from 7.9 to 10.0% v/v and glycerol from 4.8 to 6.1 g L−1. A decrease in total phenolics content, free radical-scavenging activity, and total monomeric anthocyanin content was observed following fermentation. Total flavonoids content appeared to increase after fermentation only in the cases of concentrated pomegranate and grape juice addition. In general, 22 volatile compounds were identified in PABs (13 esters, 2 fatty acids, and 7 alcohols). Major compounds detected were 3-methyl-1-butanol, 2-methyl-1-butanol, 2-phenylethanol, and ethyl acetate. These findings demonstrate the production prospect of PABs with increased ethanol content, while elaborating on the importance of fermentation temperature and the differences between the selected types of added sugars on end-product composition.

Modelado de las cinéticas de crecimiento, actividad antioxidante e hipoglucemiante a diferentes temperaturas de Lactobacillus spp. potencialmente probióticos

The effect of fermentation temperature (32, 37 and 42 °C) on the growth and in vitro antioxidant and hypoglycemic activity of Lactobacillus plantarum, L. pentosus and L. acidipiscis isolated from Chiapas cheese previously characterized as potential probiotics, were evaluated in the present research. The Unified-Gompertz method was used to model the bacterial growth of the strains (R>0.987). Similar biomass production was obtained at the end of 32 °C and 37°C. The maximum absolute growth rate was 0.526 h-1 for L. acidipiscis at 37°C. The antioxidant activity resulted maximum in DPPH at 32°C and 14 h in L. pentosus (7402.62 ± 318.52 μM Trolox/mL) and in ABTS at 32 °C and 24 h in L. acidipiscis (1612.94 ± 56.71 μM Trolox/mL).The inhibition of α-amylase (%) and α-glucosidase (%) resulted maximum at 37 °C and 24 h for L. acidipiscis (97.084 ± 0.752 and 99.756 ± 0.104, respectively). These results concluded that the three strains could be considered mesophilic and with antioxidant and hypoglycemic activity. Moreover, L. acidipiscis gave the best results in all the experiments done. So, more research should be done with this strain to better stablish its potential health benefits

Effect of fermentation temperature on volatile compounds of Petit Verdot red wines from the Spanish region of La Mancha (central-southeastern Spain)

The aim of this work was to research the relationship between volatile composition of Petit Verdot red wines and the fermentation temperature. Winemaking process was carried out at 17 °C, 21 °C, and 25 °C temperatures. Solid-phase extraction (SPE) and gas chromatography–mass spectrometry (GC–MS) were used to analyse volatile compounds. The odour activity values (OAVs) from the different compounds were classified into seven odorant series that describe the aroma profile (fruity, floral, green/fresh, sweet, spicy, fatty, and other odours). The value of each aromatic series was obtained by adding the OAVs of the volatile compounds to each series. The volatile composition was significantly affected by the temperature of the fermentation. In general, the increase in the fermentation temperature of La Mancha Petit Verdot red wines from 17 to 25 °C produced an increase in the concentration of volatile aroma compounds. The highest aroma contributions to Petit Verdot wine were fruity, sweet and floral series, followed by fatty and spicy series, regardless of fermentation temperature. The highest values of aromatic series were found in wines fermented at 21 °C. The results of this work show that changes in the fermentation temperature of wines can have a significant impact on their volatile compound profile.

Utilization of Fruit Waste for Bioethanol Production by Co-cultures of Aspergillus niger and Saccharomyces cerevisiae

The purpose of this research was to study the effectiveness of simultaneous fermentation offruit waste with co-cultures of Aspergillus niger TISTR 3063 and Saccharomyces cerevisiaeTISTR 5606 in production of ethanol. The effect of fermentation temperature on ethanol yield was also observed. Pomelo and banana peels were selected as substrates and prepared by chopping into small rectangular pieces. Fermentation of batches of fruit waste was carriedout using a 250mL Erlenmeyer flask with glucose as a control. Analysis of the composition of the fruit waste included sugar, pH, TS, VS, ash, moisture, COD and TKN. From the results, it was found that maximum yields of 90.71% and 104.90% for pomelo and banana peel, respectively, were achieved at a temperature of 40°C within 24 h. The analysis also showed that fermentation temperature affected ethanol yield. When the fermentation temperature was raised from 30°C to 40°C, maximum ethanol yield from pomelo peel fermentation with10% of inoculum was increased from 73.86% to 90.71%, significant at p-0.05 Maximum yield from banana peel fermentation showed a similar trend. This study establishes the potential for upgrading fruit wastes such as pomelo and banana peels as high value substrates for ethanol production. Pomelo peel in particular shows high potential as a substrate for ethanol fermentation at 40°C for 24 h, with inoculum of 10% (w/w) of each fungus and yeast.

Effect of fermentation temperature on the properties of exopolysaccharides and the acid gelation behavior for milk fermented by Streptococcus thermophilus strains DGCC7785 and St-143

We investigated the effect of fermenting milk with 2 strains (DGCC7785 and St-143) of Streptococcus thermophilus, which are known to produce different types of exopolysaccharide (EPS) structures. The yields and physical properties of these ropy EPS were monitored during the fermentation of milk at different temperatures. We wanted to understand how these types of EPS properties affected yogurt gelation. Reconstituted skim milk was fermented at 33, 39, or 45°C until pH values reached 5.2, 4.9, 4.7, and 4.5. Molar mass of ropy EPS samples was determined using size exclusion chromatography coupled with multiangle laser light scattering. Rheological properties of fermented milk gels were analyzed using small-strain dynamic oscillatory measurements. In both strains, concentrations of ropy EPS increased during fermentation and at all temperatures. Fermentation times, by both strains, were shortest at 45°C and longest at 33°C. For both strains, molar mass of ropy EPS ranged from 2 to 4 × 106 g/mol during fermentation. A major proteinaceous contaminant that was co-isolated with the ropy EPS fraction by our isolation method was identified as a milk-derived phosphoglycoprotein PP3. Increase in fermentation temperature from 33 to 45°C significantly decreased the storage modulus values (from 170 to 41 Pa) for milk gelled by strain DGCC7785, whereas the gels made with St-143 had very low storage modulus values (11-17 Pa) regardless of fermentation temperatures. For both strains, the values of maximum loss tangent in the milk gels increased with fermentation temperature; the maximum loss tangent occurred at higher pH values when milk was fermented by strain DGCC7785. The specific type of EPS produced appeared to be responsible for the differences in yogurt texture rather than the concentration or molar mass of the EPS.

Effect of Fermentation Temperature and Salt Concentration on Changes in Quality Index of Salted Shrimp During Fermentation

Effect of Fermentation Temperature and Salt Concentration on Changes in Quality Index of Salted Shrimp During Fermentation

Effect of fermentation temperature on hydrogen production from xylose and the succession of hydrogen‐producing microflora

AbstractBACKGROUNDHydrogen production through anaerobic dark fermentation is considered to be a potential biological process for xylose utilization. Temperature is one of the most important environmental factors, however, most studies have been carried out over a small temperature range. Batch tests were carried out to investigate the temperature effect on hydrogen production from xylose using a mixed culture over a wide temperature range (35–65°C). Hydrogen production, metabolite distribution and dynamics of microbial communities were investigated.RESULTSHydrogen‐producing cultures were successfully enriched at each tested temperature. Two peaks of fermentation temperature for hydrogen production were observed at 35 and 55°C (1.11 and 1.30 mol‐H2 mol−1‐xyloseconsumed, respectively). Butyrate and acetate were the major liquid metabolites at 35–60°C. While at 65°C the main by‐product was ethanol. Polymerase chain reaction‐denaturing gradient gel electrophoresis (PCR‐DGGE) analysis indicated that Clostridium species were dominant at 35–40°C, while Thermoanaerobacterium dominated at 45–60°C. Both species were found at 65°C, but with lowest microbial community diversity.CONCLUSIONHydrogen production efficiency was mainly affected by the liquid metabolite distributions, which depended mainly upon the temperature. Several microbial community structures were formed at mesophilic, transition, thermophilic and extreme‐thermophilic conditions, resulting in different metabolic pathways of xylose and hydrogen production capacity. © 2017 Society of Chemical Industry

Fermentation optimization of goat milk with Lactobacillus acidophilus and Bifidobacterium bifidum by Box-Behnken design.

Goat milk is only limited to the processing of goat milk powder and liquid milk, the products are mainly about milk powder and a few of them are made as milk tablet. Therefore, the study of probiotic goat milk will have great significance in the full use of goats and the development of the goat milk industry in China. The effect of fermentation temperature (35°C, 37°C, 39°C), strain ratio (1:1:1, 2:1:1, 3:1:1) and inoculum size (4%, 5%, 6%) on viable counts of L. acidophilus and B. bifidum, total bacteria and sensory value during fermentation process of L. acidophilus and B. bifidum goat yogurt (AB-goat yogurt) was investigated. The optimum fermentation conditions for AB-goat yogurt were: fermentation temperature 38°C, the strain ratio 2:1:1, inoculum size 6%. Under the optimum conditions, the viable counts of B. bifidum, L. acidophilus, total bacteria and sensory value reached (4.30 ±0.11)×107 cfu/mL, (1.39 ±0.09)×108 cfu/mL, (1.82±0.06)×109 cfu/mL and 7.90 ±0.14, respectively. The fermentation temperature, the strain ratio and inoculum size had a significant effect on the fermentation of AB-goat yogurt and these results are beneficial for developing AB-goat yogurt.

Hibiscus sabdariffa (Roselle) Extracts and Wine: Phytochemical Profile, Physicochemical Properties, and Carbohydrase Inhibition.

Three varieties of Hibiscus sabdariffa were analyzed for their phytochemical content and inhibitory potential on carbohydrate-digesting enzymes as a basis for selecting a variety for wine production. The dark red variety was chosen as it was highest in phenolic content and an aqueous extract partially inhibited α-glucosidase (maltase), with delphinidin 3-O-sambubioside, cyanidin 3-O-sambubioside, and 3-O-caffeoylquinic acid accounting for 65% of this activity. None of the varieties significantly inhibited α-amylase. Regarding Hibiscus sabdariffa wine, the effect of fermentation temperature (20 and 30 °C) on the physicochemical, phytochemical, and aroma composition was monitored over 40 days. The main change in phytochemical composition observed was the hydrolysis of 3-O-caffeolquinic acid and the concomitant increase of caffeic acid irrespective of fermentation temperature. Wine fermented at 20 °C was slightly more active for α-glucosidase inhibition with more fruity aromas (ethyl octanoate), but there were more flowery notes (2-phenylethanol) at 30 °C.

The Effect of Fermentation Temperature on the Microstructure, Physicochemical and Rheological Properties of Probiotic Buffalo Yoghurt

The properties of buffalo and bovine milk differ and the procedures developed to make bovine yoghurt may require optimisation for the production of buffalo yoghurt. This study aimed to apply cryo-scanning electron microscopy and confocal laser scanning microscopy to determine the optimal temperature for processing buffalo yoghurt. Milk was fermented at three different temperatures (37, 40 and 43 °C), stored for 28 days and the yoghurt microstructure, physicochemical and rheological properties assessed. Yoghurt fermented at 37 °C had a compact microstructure and the probiotic Lactobacillus acidophilus La-5 was more viable on storage. In contrast, yoghurt produced from a faster fermentation at 43 °C was firmer with a more porous microstructure that exhibited a higher degree of syneresis. The rheological properties during storage including the thixotropy, consistency coefficient and flow behaviour index were not significantly affected by temperature nor were the concentration of lactose, ionic calcium or titratable acidity. This study shows how changes to processing can be used to alter the microstructure of buffalo products and suggests that a decrease in fermentation temperature could be used to improve the quality of buffalo yoghurt.

Low amplitude oscilatory determinations for suero costeño

The Suero Costeno is a traditional fermented milk product of the Colombian Atlantic Coast. The simultaneous effect of fermentation temperature, milk total solid level and total inoculum concentration on the value of storage module (G'), and tangent loss were studied by means of the response surface methodology with three variables and five levels. Statistical treatments resulted in developments of mathematical models. The models explain that the total solids diminish significantly the minimum tangent loss and syneresis of the Suero Costeno. These models can be used to improve the quality of Suero Costeno.

Effect of fermentation temperature on chemical composition of mescals made from Agave duranguensis juice with different native yeast genera

In this study, the fermentation behavior at 18 and 28°C of different native yeast genera on juice from Agave duranguensis was evaluated and the volatile compounds produced in the obtained mescals from these fermentations were identified. The fermentative capacity of Hanseniaspora uvarum, Kluyveromyces marxianus and Saccharomyces cerevisiae increased at 28°C; however, the fermentation behavior of Torulaspora delbrueckii was not affected by temperature. In the mescals produced by H. uvarum, T. delbrueckii and S. cerevisiae a greater number and abundance of compounds were identified at 18°C than at 28°C. Conversely , K. marxianus showed a higher production of these compounds at 28°C. Some compounds identified in all mescals were 2-methyl-1-propanol, 3-methyl-1-butanol, acetic acid, 1-(2-furanyl)-ethanone, furfural, α-terpineol, ethyl phenyl acetate and phenyl ethyl alcohol. For strains H. uvarum, T. delbrueckii and S. cerevisiae , the most abundant compound identified was 3-methyl-1-butanol at both temperatures. However, for K. marxianus, phenyl ethyl acetate was the most abundant. The non-Saccharomyces genera studied, exhibit different behaviors to those reported for wine fermentation when the same genera was used. Therefore, they presented a major fermentative capacity and also volatile compounds characteristic of mescals were produced.

The effect of fermentation temperature on the functional dairy product quality

The aim of this study was to examine the possibility of fermented dairy beverage production by the application of kombucha cultivated on thyme tea in combination with a probiotic starter and to evaluate the quality of the new functional product. Fermented dairy beverages are produced from milk with 1.6% milk fat at three fermentation temperatures: 37?C, 40?C and 43?C.Chemical quality, rheological properties and products of added starter cultures metabolism were determined in the fermented dairy beverages after production and after10 days of storage. Produced fermented dairy beverages have reduced milk fat content and good textural characteristics. Besides the highly valuable milk components, they contain numerous compounds which have pronounced therapeutic properties. These products could be used as functional food in the diet of different populations for health improvement.

Optimization study of ethanolic fermentation from oil palm trunk, rubberwood and mixed hardwood hydrolysates using Saccharomyces cerevisiae

Ethanolic fermentation using Saccharomyces cerevisiae was carried out on three types of hydrolysates produced from lignocelulosic biomass which are commonly found in Malaysia such as oil palm trunk, rubberwood and mixed hardwood. The effect of fermentation temperature and pH of hydrolysate was evaluated to optimize the fermentation efficiency which defined as maximum ethanol yield in minimum fermentation time. The fermentation process using different temperature of 25 °C, 30 °C and 40 °C were performed on the prepared fermentation medium adjusted to pH 4, pH 6 and pH 7, respectively. Results showed that the fermentation time was significantly reduced with the increase of temperature but an adverse reduction in ethanol yield was observed using temperature of 40 °C. As the pH of hydrolysate became more acidic, the ethanol yield increased. Optimum fermentation efficiency for ethanolic fermentation of lignocellulosic hydrolysates using S. cerevisiae can be obtained using 33.2 °C and pH 5.3.

Effect of fermentation temperature on validamycin A production by Streptomyces hygroscopicus 5008

Validamycin A (VAL-A), produced by Streptomyces hygroscopicus, is an important anti-fungal agro-antibiotic. In this work, the effect of fermentation temperature on VAL-A biosynthesis by S. hygroscopicus 5008 was investigated between 28 °C and 42 °C, and an interesting threshold of temperature for VAL-A biosynthesis was found between 35 °C and 37 °C. At a relatively higher temperature, a much higher VAL-A productivity was obtained together with faster protein synthesis and sugar consumption. Transcriptional analysis of samples from early, middle and late stages of fermentation at various temperatures demonstrated that three operons, valABC, valKLMN and valG, for all eight necessary structure genes, were dramatically promoted when temperature reached the threshold. Activities of both glucose-6-phosphate dehydrogenase (G6PDH) of pentose-phosphate pathway and ValG of VAL-A biosynthesis were also enhanced at a higher cultivation temperature. The interesting temperature effect with a 2 °C threshold shift from 35 °C to 37 °C on the antibiotic biosynthesis was understood to be related to the gene transcriptional levels and key enzyme activities.

Effect of fermentation temperature on the microbial and physicochemical properties of silver carp sausages inoculated with Pediococcus pentosaceus

The effect of fermentation with Pediococcus pentosaceus at different temperatures ranging from 15 to 37 °C on the quality characteristics of silver carp sausages was investigated. Higher temperature stimulated the rapid growth of lactic acid bacteria, resulting in a rapid decline in pH, and consequently suppressed the growth of Pseudomonas, Micrococcaceae and Enterobacteriaceae. However, increasing fermentation temperature gave a progressive increase in total volatile basic nitrogen and biogenic amines in fermented silver carp sausages. Histamine was the main biogenic amine, exceeding 100 mg/kg after 48 h of fermentation at temperatures above 30 °C. Higher content of non-protein nitrogen and α-amino nitrogen correlated with the electrophoretic studies, which showed that proteolysis of high molecular weight myofibrillar and sarcoplasmic proteins was more prominent at higher fermentation temperatures. Products fermented at 23–30 °C showed greatest consumer preference and most favourable textural properties.

Effect of fermentation temperature and must processing on process productivity and product quality in mescal fermentation

We examined the quality and production yield of mescal obtained by fermentation of traditional (including bagasse) and filtered musts at three temperatures (18, 25 and 32 °C). Fermentation temperature did not affect the concentration of methanol, higher alcohols, or dry extracts, and in all cases the product met the standards of the Mexican Official Norm for these compounds. On the other hand, the acidity of the product fell within specifications only for fermentations performed at 18 °C (either must) or 32 °C (filtered must only). Processing at the higher temperature also resulted in increased productivity, demonstrating that fermentation of filtered musts at 32 °C is a useful means of improving both the quality and throughput of mescal production.

Effect of fermentation temperature on hydrogen production from cow waste slurry by using anaerobic microflora within the slurry

We examined hydrogen production from a dairy cow waste slurry (13.4 g of volatile solids per liter) by batch cultures in a temperature range from 37 to 85 degrees C, using microflora naturally present within the slurry. Without the addition of seed bacteria, hydrogen was produced by simply incubating the slurry, using the microflora within the slurry. Interestingly, two peaks of fermentation temperatures for hydrogen production from the slurry were observed at 60 and 75 degrees C (392 and 248 ml H2 per liter of slurry, respectively). After the termination of the hydrogen evolution, the microflora cultured at 60 degrees C displayed hydrogen-consuming activity, but hydrogen-consuming activity of the microflora cultured at 75 degrees C was not detected, at least for 24 days. At both 60 and 75 degrees C, the main by-product was acetate, and the optimum pH of the slurry for hydrogen production was around neutral. Bacteria related to hydrogen-producing moderate and extreme thermophiles, Clostridium thermocellum and Caldanaerobacter subterraneus, were detected in the slurries cultured at 60 and 75 degrees C, respectively, by denaturing gradient gel electrophoresis analyses, using the V3 region of 16S rDNA.