22 results on '"Aleksei Kaleda"'
Search Results
2. Erratum to 'Physicochemical, textural, and sensorial properties of fibrous meat analogs from oat-pea protein blends extruded at different moistures, temperatures, and screw speeds' [Future Foods, 4 (2021) 100092]
- Author
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Aleksei Kaleda, Karel Talvistu, Helen Vaikma, Mari-Liis Tammik, Sirli Rosenvald, and Raivo Vilu
- Subjects
Nutrition. Foods and food supply ,TX341-641 ,Food processing and manufacture ,TP368-456 - Published
- 2022
- Full Text
- View/download PDF
3. Water sorption behaviour of commercial furcellaran
- Author
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Kairit Eha, Aleksei Kaleda, Anne Menert, and Katrin Laos
- Subjects
Furcellaran ,Sorption isotherm ,Modelling ,Net isosteric heat of sorption ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Water sorption isotherms are important tool for designing the technological processes and predicting stability and shelf life of food. The aim of the work was to determine the water sorption isotherms of commercial furcellaran at different temperatures (20, 35 and 50 °C) using a gravimetric method under different levels of relative humidity (19–95%). The experimental data obtained have been interpreted in the terms of various isotherm models and it was found that the best results were obtained with the Peleg model (P < 2.1%; RSME
- Published
- 2022
- Full Text
- View/download PDF
4. Techno-Functional and Sensory Characterization of Commercial Plant Protein Powders
- Author
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Kadi Jakobson, Aleksei Kaleda, Karl Adra, Mari-Liis Tammik, Helen Vaikma, Tiina Kriščiunaite, and Raivo Vilu
- Subjects
plant proteins ,functional properties ,water solubility ,water-holding capacity ,emulsification ,foaming ,Chemical technology ,TP1-1185 - Abstract
Many new plant proteins are appearing on the market, but their properties are insufficiently characterized. Hence, we collected 24 commercial proteins from pea, oat, fava bean, chickpea, mung bean, potato, canola, soy, and wheat, including different batches, and assessed their techno-functional and sensory properties. Many powders had yellow, red, and brown color tones, but that of fava bean was the lightest. The native pH ranged from 6.0 to 7.7. The water solubility index was 28% on average, but after heat treatment the solubility typically increased. Soy isolate had by far the best water-holding capacity of 6.3 g (H2O) g−1, and canola had the highest oil-holding capacity of 2.8 g (oil) g−1. The foaming capacity and stability results were highly varied but typical to the raw material. The emulsification properties of all powders were similar. Upon heating, the highest viscosity and storage modulus were found in potato, canola, and mung bean. All powders had raw material flavor, were bitter and astringent, and undissolved particles were perceived in the mouth. Large differences in functionality were found between the batches of one pea powder. In conclusion, we emphasize the need for methodological standardization, but while respecting the conditions found in end applications like meat and dairy analogs.
- Published
- 2023
- Full Text
- View/download PDF
5. Optimisation of sample storage and DNA extraction for human gut microbiota studies
- Author
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Jekaterina Kazantseva, Esther Malv, Aleksei Kaleda, Aili Kallastu, and Anne Meikas
- Subjects
Human gut microbiota ,16S rRNA gene sequencing ,Faecal DNA extraction ,Faecal sample storage ,Illumina iSeq 100, DNA/RNA Shield solution ,Microbiology ,QR1-502 - Abstract
Abstract Background New developments in next-generation sequencing technologies and massive data received from this approach open wide prospects for personalised medicine and nutrition studies. Metagenomic analysis of the gut microbiota is paramount for the characterization of human health and wellbeing. Despite the intensive research, there is a huge gap and inconsistency between different studies due to the non-standardised and biased pipeline. Methodical and systemic understanding of every stage in the process is necessary to overcome all bottlenecks and grey zones of gut microbiota studies, where all details and interactions between processes are important. Results Here we show that an inexpensive, but reliable iSeq 100 platform is an excellent tool to perform the analysis of the human gut microbiota by amplicon sequencing of the 16 S rRNA gene. Two commercial DNA extraction kits and different starting materials performed similarly regarding the taxonomic distribution of identified bacteria. DNA/RNA Shield reagent proved to be a reliable solution for stool samples collection, preservation, and storage, as the storage of faecal material in DNA/RNA Shield for three weeks at different temperatures and thawing cycles had a low impact on the bacterial distribution. Conclusions Altogether, a thoroughly elaborated pipeline with close attention to details ensures high reproducibility with significant biological but not technical variations.
- Published
- 2021
- Full Text
- View/download PDF
6. Market mapping of plant-based milk alternatives by using sensory (RATA) and GC analysis
- Author
-
Helen Vaikma, Aleksei Kaleda, Julia Rosend, and Sirli Rosenvald
- Subjects
Plant-based beverage ,Milk alternative ,Sensory profile ,Volatile profile ,RATA ,Nutrition. Foods and food supply ,TX341-641 ,Food processing and manufacture ,TP368-456 - Abstract
It is evident that the interest in plant-based milk alternative products is increasing, although there are still difficulties with undesired sensorial properties. This study seeks to contribute to sustainable food development through a better understanding of the market situation. The objective of this study was to get a comprehensive overview of 90 plant-based beverages currently available on the Estonian market. Main focus of this research was to map the plant-based beverage market sensorially. To evaluate such a large set of samples, RATA (Rate-All-That-Apply) was explored as a method for market mapping. A wide range of products made from different raw materials was characterized. Sensory analysis was able to make some conclusions based on specific raw materials, as there was a lot of variety among different sample groups. Combining the data collected from sensory and aroma analysis (GC/MS/O) helped to further examine the effect of volatile compounds on sensory properties of various product types. Some key compounds were found in different products, including compounds that may be causing off-flavors.
- Published
- 2021
- Full Text
- View/download PDF
7. Physicochemical, textural, and sensorial properties of fibrous meat analogs from oat-pea protein blends extruded at different moistures, temperatures, and screw speeds
- Author
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Aleksei Kaleda, Karel Talvistu, Helen Vaikma, Mari-Liis Tammik, Sirli Rosenvald, and Raivo Vilu
- Subjects
Low-moisture extrusion ,Meat analog ,Pea protein ,Oat protein ,Nutrition. Foods and food supply ,TX341-641 ,Food processing and manufacture ,TP368-456 - Abstract
This study investigated meat analogs produced using low-moisture extrusion from oat and pea protein blends at ratios 20:80, 30:70, 50:50, and 70:30. Response surface methodology was used to assess the effect of blend composition, screw speed (200–1200 rpm), barrel temperature (135–160 °C), and moisture content (25–35%) on the properties of extruded meat analogs. Blend composition had a relatively stronger effect on water holding capacity, water solubility index, bitterness, cohesiveness, and springiness, while extrusion conditions had more influence on hardness, fibrousness, and moistness. As the oat content increased from 20% to 70% the maximum sensory fibrousness increased from 7.2 to 8.6 on a scale of 0–9. Although the mean water holding capacity decreased from 2.1 to 1.4 g g−1, the mean sensory moistness remained around 4.1. Cereal taste dominated over legumes with the mean intensities 3.9 and 2.0, however, the differences between oat-pea blends were small. In general, the extruded meat analogs had a mild flavor and high fibrousness, and the developed response surface models can be used to tune the properties further. This confirms that oat protein in combination with pea is a practical alternative to soy and gluten proteins for the production of meat analogs.
- Published
- 2021
- Full Text
- View/download PDF
8. How to Balance the Yield and Protein Content of Air-classified Pulse Flour: the Influence of the Restriction Valve
- Author
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Davide De Angelis, Aleksei Kaleda, Antonella Pasqualone, Helen Vaikma, Giacomo Squeo, Francesco Caponio, and Carmine Summo
- Subjects
Chemical engineering ,TP155-156 ,Computer engineering. Computer hardware ,TK7885-7895 - Abstract
Dry fractionation by air classification is a sustainable process applied to cereals and pulses to produce protein and starch concentrates. The process involves using a series of cyclones equipped with either a classifier wheel or a restriction valve, which allow to separate a coarse starch-rich fraction and a fine protein-rich fraction. In this study, an apparatus with an air restriction valve was used, with the aim of studying the influence of two set-ups of the air classification system, on the protein content, yield, protein separation efficiency, and physicochemical and functional properties of the resulting fractions. The tighter restriction valve set-up (lower air flow and air speed compared to a more opened set-up) caused an increase in the protein content in the fine protein-rich fraction from 53.9% to 61.9%, but the drawback was a 47% yield decrease and a decrease in the protein separation efficiency. The results highlighted that the dry fractionation process should be carefully calibrated in order to balance the yield and the chemical composition (e.g. the protein content) of the fractions. In particular, the more opened set-up was better capable of balancing these two parameters, indicating that a high air flow is necessary for pulse flour. Moreover, the set-up of the restriction valve did not significantly influence effect on the physicochemical and functional properties of the fraction, pointing out that even a protein-rich fraction with a 50% protein content could be successfully used as a food ingredient.
- Published
- 2021
- Full Text
- View/download PDF
9. Impact of short-term heat treatment on the structure and functional properties of commercial furcellaran compared to commercial carrageenans
- Author
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Kairit Eha, Tõnis Pehk, Ivo Heinmaa, Aleksei Kaleda, and Katrin Laos
- Subjects
Carrageenan ,NMR ,Molecular weight ,Rheology ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
In the production of biopolymers, the processing operations (e.g. extraction and drying) involve some degradation of the polysaccharide-causing structural and functional changes in final products. In this study, short-term heat treatment (75–115 °C, 15 min) influence on commercial carrageenans' — furcellaran, κ-carrageenan, ι-carrageenan and a κ/λ-carrageenan — structure, molecular weight and gel rheology was studied. Compared with other carrageenans, commercial furcellaran that had undergone multiple heatings at high temperatures during production was found to be susceptible to polymer degradation. Heat caused the desulphation and degradation of furcellaran galactans and the molecular weight was significantly decreased, causing a drop in viscosity and gel hardness. The loss of the network cross-linking of furcellaran gels was confirmed by scanning electron microscopy. Carrageenan gel storage modulus values decreased with the increase in the temperature of the treatment. The greatest decrease in storage modulus values occurred with κ/λ-carrageenan gels, followed by ι-carrageenan > furcellaran > κ-carrageenan.
- Published
- 2021
- Full Text
- View/download PDF
10. Physicochemical and Sensorial Evaluation of Meat Analogues Produced from Dry-Fractionated Pea and Oat Proteins
- Author
-
Davide De Angelis, Aleksei Kaleda, Antonella Pasqualone, Helen Vaikma, Martti Tamm, Mari-Liis Tammik, Giacomo Squeo, and Carmine Summo
- Subjects
extrusion cooking ,extruder responses ,dry fractionation ,pea protein ,plant-based meat analogues ,sustainability ,Chemical technology ,TP1-1185 - Abstract
Pea protein dry-fractionated (PDF), pea protein isolated (PIs), soy protein isolated (SIs) and oat protein (OP) were combined in four mixes (PDF_OP, PIs_OP, PDF_PIs_OP, SIs_OP) and extruded to produce meat analogues. The ingredients strongly influenced the process conditions and the use of PDF required higher specific mechanical energy and screw speed to create fibrous texture compared to PIs and SIs. PDF can be conveniently used to produce meat analogues with a protein content of 55 g 100 g−1, which is exploitable in meat-alternatives formulation. PDF-based meat analogues showed lower hardness (13.55–18.33 N) than those produced from PIs and SIs (nearly 27 N), probably due to a more porous structure given by the natural presence of carbohydrates in the dry-fractionated ingredient. PDF_OP and PIs_PDF_OP showed a significantly lower water absorption capacity than PIs OP and SIs_OP, whereas pea-based extrudates showed high oil absorption capacity, which could be convenient to facilitate the inclusion of oil and fat in the final formulation. The sensory evaluation highlighted an intense odor and taste profile of PDF_OP, whereas the extrudates produced by protein isolates had more neutral sensory characteristics. Overall, the use of dry-fractionated protein supports the strategies to efficiently produce clean-labeled and sustainable plant-based meat analogues.
- Published
- 2020
- Full Text
- View/download PDF
11. The Effect of Apple Juice Concentration on Cider Fermentation and Properties of the Final Product
- Author
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Julia Rosend, Aleksei Kaleda, Rain Kuldjärv, Georg Arju, and Ildar Nisamedtinov
- Subjects
cider ,juice concentrate ,fermentation ,gas chromatography ,volatile esters ,hydrogen sulfide ,Chemical technology ,TP1-1185 - Abstract
European legislation overall agrees that apple juice concentrate is allowed to be used to some extent in cider production. However, no comprehensive research is available to date on the differences in suitability for fermentation between fresh apple juice and that of reconstituted apple juice concentrate. This study aimed to apply freshly pressed juice and juice concentrate made from the same apple cultivar as a substrate for cider fermentation. Differences in yeast performance in terms of fermentation kinetics and consumption of nutrients have been assessed. Fermented ciders were compared according to volatile ester composition and off-flavor formation related to hydrogen sulfide. Based on the results, in the samples fermented with the concentrate, the yeasts consumed less fructose. The formation of long-chain fatty acid esters increased with the use of reconstituted juice concentrate while the differences in off-flavor formation could not be determined. Overall, the use of the concentrate can be considered efficient enough for the purpose of cider fermentation. However, some nutritional supplementation might be required to support the vitality of yeast.
- Published
- 2020
- Full Text
- View/download PDF
12. Impact of Fermentation and Phytase Treatment of Pea-Oat Protein Blend on Physicochemical, Sensory, and Nutritional Properties of Extruded Meat Analogs
- Author
-
Aleksei Kaleda, Karel Talvistu, Martti Tamm, Maret Viirma, Julia Rosend, Kristel Tanilas, Marie Kriisa, Natalja Part, and Mari-Liis Tammik
- Subjects
meat analog ,extrusion ,fermentation ,phytic acid ,Chemical technology ,TP1-1185 - Abstract
Plant materials that are used for the production of extruded meat analogs are often nutritionally incomplete and also contain antinutrients, thus there is a need to explore alternative plant proteins and pre-treatments. This study demonstrates application of phytase and fermentation to a pea-oat protein blend with a good essential amino acid profile and subsequent texturization using extrusion cooking. Enzymatic treatment reduced the content of antinutrient phytic acid by 32%. Extrusion also degraded phytic acid by up to 18%, but the effect depended on the material. Differences in physicochemical, sensorial, and textural properties between untreated and phytase-treated extruded meat analogs were small. In contrast, fermented material was more difficult to texturize due to degradation of macromolecules; physicochemical and textural properties of extrudates were markedly different; sensory analysis showed enhancement of flavor, but also detected an increase in some unwanted taste attributes (bitterness, cereal and off-taste). Phytic acid was not degraded by fermentation. Analysis of volatile compounds showed extrusion eliminated volatiles from the raw material but introduced Maillard reaction products. Overall, phytase treatment and fermentation demonstrated the potential for application in extruded meat analogs but also highlighted the necessity of optimization of process conditions.
- Published
- 2020
- Full Text
- View/download PDF
13. Optimisation of sample storage and DNA extraction for human gut microbiota studies
- Author
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Aili Kallastu, Anne Meikas, Jekaterina Kazantseva, Esther Malv, and Aleksei Kaleda
- Subjects
DNA, Bacterial ,Microbiology (medical) ,Sample (material) ,Preservation, Biological ,Computational biology ,Biology ,Gut flora ,Microbiology ,Illumina iSeq 100, DNA/RNA Shield solution ,Feces ,03 medical and health sciences ,Human health ,Human gut ,Faecal sample storage ,RNA, Ribosomal, 16S ,Faecal DNA extraction ,Humans ,16S rRNA gene sequencing ,030304 developmental biology ,0303 health sciences ,Bacteria ,030306 microbiology ,High-Throughput Nucleotide Sequencing ,biology.organism_classification ,DNA extraction ,QR1-502 ,Gastrointestinal Microbiome ,Metagenomics ,16s rrna gene sequencing ,Amplicon sequencing ,Human gut microbiota ,Research Article - Abstract
Background New developments in next-generation sequencing technologies and massive data received from this approach open wide prospects for personalised medicine and nutrition studies. Metagenomic analysis of the gut microbiota is paramount for the characterization of human health and wellbeing. Despite the intensive research, there is a huge gap and inconsistency between different studies due to the non-standardised and biased pipeline. Methodical and systemic understanding of every stage in the process is necessary to overcome all bottlenecks and grey zones of gut microbiota studies, where all details and interactions between processes are important. Results Here we show that an inexpensive, but reliable iSeq 100 platform is an excellent tool to perform the analysis of the human gut microbiota by amplicon sequencing of the 16 S rRNA gene. Two commercial DNA extraction kits and different starting materials performed similarly regarding the taxonomic distribution of identified bacteria. DNA/RNA Shield reagent proved to be a reliable solution for stool samples collection, preservation, and storage, as the storage of faecal material in DNA/RNA Shield for three weeks at different temperatures and thawing cycles had a low impact on the bacterial distribution. Conclusions Altogether, a thoroughly elaborated pipeline with close attention to details ensures high reproducibility with significant biological but not technical variations.
- Published
- 2021
14. Physicochemical, textural, and sensorial properties of fibrous meat analogs from oat-pea protein blends extruded at different moistures, temperatures, and screw speeds
- Author
-
Sirli Rosenvald, Helen Vaikma, Raivo Vilu, Mari-Liis Tammik, Aleksei Kaleda, and Karel Talvistu
- Subjects
Taste ,Aqueous solution ,Chemistry ,Nutrition. Foods and food supply ,Pea protein ,Meat analog ,Oat protein ,TP368-456 ,Food processing and manufacture ,Composition (visual arts) ,Extrusion ,TX341-641 ,Response surface methodology ,Food science ,Low-moisture extrusion ,Water content ,Flavor ,Food Science - Abstract
This study investigated meat analogs produced using low-moisture extrusion from oat and pea protein blends at ratios 20:80, 30:70, 50:50, and 70:30. Response surface methodology was used to assess the effect of blend composition, screw speed (200–1200 rpm), barrel temperature (135–160 °C), and moisture content (25–35%) on the properties of extruded meat analogs. Blend composition had a relatively stronger effect on water holding capacity, water solubility index, bitterness, cohesiveness, and springiness, while extrusion conditions had more influence on hardness, fibrousness, and moistness. As the oat content increased from 20% to 70% the maximum sensory fibrousness increased from 7.2 to 8.6 on a scale of 0–9. Although the mean water holding capacity decreased from 2.1 to 1.4 g g−1, the mean sensory moistness remained around 4.1. Cereal taste dominated over legumes with the mean intensities 3.9 and 2.0, however, the differences between oat-pea blends were small. In general, the extruded meat analogs had a mild flavor and high fibrousness, and the developed response surface models can be used to tune the properties further. This confirms that oat protein in combination with pea is a practical alternative to soy and gluten proteins for the production of meat analogs.
- Published
- 2021
15. Market mapping of plant-based milk alternatives by using sensory (RATA) and GC analysis
- Author
-
Aleksei Kaleda, Helen Vaikma, Julia Rosend, and Sirli Rosenvald
- Subjects
Volatile profile ,Computer science ,business.industry ,Nutrition. Foods and food supply ,Sensory profile ,Plant based ,Sample (statistics) ,Sensory system ,Raw material ,TP368-456 ,Product type ,Sensory analysis ,Plant-based beverage ,Food processing and manufacture ,Biotechnology ,Milk alternative ,Sustainable agriculture ,TX341-641 ,business ,RATA ,Food Science - Abstract
It is evident that the interest in plant-based milk alternative products is increasing, although there are still difficulties with undesired sensorial properties. This study seeks to contribute to sustainable food development through a better understanding of the market situation. The objective of this study was to get a comprehensive overview of 90 plant-based beverages currently available on the Estonian market. Main focus of this research was to map the plant-based beverage market sensorially. To evaluate such a large set of samples, RATA (Rate-All-That-Apply) was explored as a method for market mapping. A wide range of products made from different raw materials was characterized. Sensory analysis was able to make some conclusions based on specific raw materials, as there was a lot of variety among different sample groups. Combining the data collected from sensory and aroma analysis (GC/MS/O) helped to further examine the effect of volatile compounds on sensory properties of various product types. Some key compounds were found in different products, including compounds that may be causing off-flavors.
- Published
- 2021
16. Characterisation of chemical, microbial and sensory profiles of commercial kombuchas
- Author
-
Maret Andreson, Jekaterina Kazantseva, Rain Kuldjärv, Esther Malv, Helen Vaikma, Aleksei Kaleda, Mary-Liis Kütt, and Raivo Vilu
- Subjects
Beverages ,Tea ,Yeasts ,Fermentation ,General Medicine ,Microbiology ,Camellia sinensis ,Food Science - Abstract
The kombucha market is a fast-growing segment in the functional beverage category. The selection of kombuchas on the market varies between the traditional and flavoured kombuchas. Our research aimed to characterise the chemical, microbial, and sensory profiles of the commercial kombuchas. We analysed 16 kombuchas from 6 producers. The dominant metabolites were acetate, lactate, and ethanol, the last of which might put some kombuchas into the alcoholic beverage section in some countries. The metagenomic analyses demonstrated that LAB dominates in green tea, and AAB in black tea kombuchas. The main bacterial species were Komagataeibacter rhaeticus and Lactobacillus ssp, and yeast species Dekkera anomala and Dekkera bruxellensis. The sweet and sour balance correlated with acid concentrations. The free sorting task showed that commercial kombuchas clustered into three main categories "fruity and artificial flavour", herbal and tea notes", and "classical notes". Our research results showed the necessity of the definition of kombucha.
- Published
- 2021
17. Physicochemical and Sensorial Evaluation of Meat Analogues Produced from Dry-Fractionated Pea and Oat Proteins
- Author
-
Helen Vaikma, Giacomo Squeo, Davide De Angelis, Mari-Liis Tammik, Aleksei Kaleda, Martti Tamm, Antonella Pasqualone, and Carmine Summo
- Subjects
plant-based meat analogues ,Taste ,Health (social science) ,Absorption of water ,Plant Science ,lcsh:Chemical technology ,Health Professions (miscellaneous) ,Microbiology ,Sensory analysis ,extrusion cooking ,Article ,sensory analysis ,Ingredient ,lcsh:TP1-1185 ,Food science ,Soy protein ,pea protein ,functional properties ,extruder responses ,Chemistry ,Pea protein ,fungi ,food and beverages ,Specific mechanical energy ,dry fractionation ,sustainability ,Process conditions ,Food Science - Abstract
Pea protein dry-fractionated (PDF), pea protein isolated (PIs), soy protein isolated (SIs) and oat protein (OP) were combined in four mixes (PDF_OP, PIs_OP, PDF_PIs_OP, SIs_OP) and extruded to produce meat analogues. The ingredients strongly influenced the process conditions and the use of PDF required higher specific mechanical energy and screw speed to create fibrous texture compared to PIs and SIs. PDF can be conveniently used to produce meat analogues with a protein content of 55 g 100 g&minus, 1, which is exploitable in meat-alternatives formulation. PDF-based meat analogues showed lower hardness (13.55&ndash, 18.33 N) than those produced from PIs and SIs (nearly 27 N), probably due to a more porous structure given by the natural presence of carbohydrates in the dry-fractionated ingredient. PDF_OP and PIs_PDF_OP showed a significantly lower water absorption capacity than PIs OP and SIs_OP, whereas pea-based extrudates showed high oil absorption capacity, which could be convenient to facilitate the inclusion of oil and fat in the final formulation. The sensory evaluation highlighted an intense odor and taste profile of PDF_OP, whereas the extrudates produced by protein isolates had more neutral sensory characteristics. Overall, the use of dry-fractionated protein supports the strategies to efficiently produce clean-labeled and sustainable plant-based meat analogues.
- Published
- 2020
- Full Text
- View/download PDF
18. Impact of Fermentation and Phytase Treatment of Pea-Oat Protein Blend on Physicochemical, Sensory, and Nutritional Properties of Extruded Meat Analogs
- Author
-
Marie Kriisa, Kristel Tanilas, Maret Viirma, Aleksei Kaleda, Karel Talvistu, Martti Tamm, Natalja Part, Julia Rosend, and Mari-Liis Tammik
- Subjects
Health (social science) ,Plant Science ,Raw material ,lcsh:Chemical technology ,Health Professions (miscellaneous) ,Microbiology ,Sensory analysis ,Article ,symbols.namesake ,chemistry.chemical_compound ,lcsh:TP1-1185 ,Food science ,fermentation ,Antinutrient ,Essential amino acid ,chemistry.chemical_classification ,Phytic acid ,Chemistry ,food and beverages ,phytic acid ,Maillard reaction ,extrusion ,meat analog ,symbols ,Fermentation ,Phytase ,Food Science - Abstract
Plant materials that are used for the production of extruded meat analogs are often nutritionally incomplete and also contain antinutrients, thus there is a need to explore alternative plant proteins and pre-treatments. This study demonstrates application of phytase and fermentation to a pea-oat protein blend with a good essential amino acid profile and subsequent texturization using extrusion cooking. Enzymatic treatment reduced the content of antinutrient phytic acid by 32%. Extrusion also degraded phytic acid by up to 18%, but the effect depended on the material. Differences in physicochemical, sensorial, and textural properties between untreated and phytase-treated extruded meat analogs were small. In contrast, fermented material was more difficult to texturize due to degradation of macromolecules, physicochemical and textural properties of extrudates were markedly different, sensory analysis showed enhancement of flavor, but also detected an increase in some unwanted taste attributes (bitterness, cereal and off-taste). Phytic acid was not degraded by fermentation. Analysis of volatile compounds showed extrusion eliminated volatiles from the raw material but introduced Maillard reaction products. Overall, phytase treatment and fermentation demonstrated the potential for application in extruded meat analogs but also highlighted the necessity of optimization of process conditions.
- Published
- 2020
19. Instability of low-moisture carrageenans as affected by water vapor sorption at moderate storage temperatures
- Author
-
Katrin Laos, Natalja Part, Aleksei Kaleda, Kairit Eha, and Margus Friedenthal
- Subjects
Isothermal microcalorimetry ,Exothermic reaction ,Absorption of water ,Water activity ,Moisture ,Chemistry ,General Chemical Engineering ,General Engineering ,General Physics and Astronomy ,Thermodynamics ,Sorption ,Matrix (chemical analysis) ,General Earth and Planetary Sciences ,General Materials Science ,Water vapor ,General Environmental Science - Abstract
Isothermal microcalorimetry was used to study the exothermic heat flow caused by the absorption of water into carrageenans and a furcellaran, leading to their thermodynamic instability under moderate storage conditions (35 °C, τ = 12 h), where τ is the reaction time (h). The net heats evolved by furcellaran, ι-carrageenan, κ-carrageenan, and a mixture of κ/λ-carrageenan were 43.5 J/g, 45.9 J/g, 31.6 J/g, and 28.1 J/g, respectively. The pronounced exothermic behavior of furcellaran was attributed to the enthalpic association of water molecules with the thermally degraded carbohydrate matrix. The responses of a heat treatment of carrageenans at 55 °C, 85 °C, and 105 °C for 15 min on exothermic heat Q (J/g) at different water activities (aw = 0.26, 0.51, 0.76, and 1.0) were measured. The dependence of the net recorded heat Q on water activity can be satisfactorily approximated by the equation Q = a[1 − (1 − aw)b], where a and b are the coefficients found by the nonlinear least-squares method. It was concluded that carrageenans affected by excessive heat treatment should be preferably stored with limited water access.
- Published
- 2020
20. Impact of short-term heat treatment on the structure and functional properties of commercial furcellaran compared to commercial carrageenans
- Author
-
Aleksei Kaleda, Katrin Laos, Tõnis Pehk, Ivo Heinmaa, and Kairit Eha
- Subjects
0301 basic medicine ,Science (General) ,animal structures ,Scanning electron microscope ,animal diseases ,Carrageenan ,Molecular weight ,Q1-390 ,03 medical and health sciences ,Viscosity ,chemistry.chemical_compound ,0302 clinical medicine ,Polymer degradation ,Rheology ,H1-99 ,Multidisciplinary ,Chemistry ,Extraction (chemistry) ,Dynamic mechanical analysis ,respiratory system ,NMR ,Social sciences (General) ,carbohydrates (lipids) ,030104 developmental biology ,Chemical engineering ,Degradation (geology) ,030217 neurology & neurosurgery ,Research Article - Abstract
In the production of biopolymers, the processing operations (e.g. extraction and drying) involve some degradation of the polysaccharide-causing structural and functional changes in final products. In this study, short-term heat treatment (75–115 °C, 15 min) influence on commercial carrageenans' — furcellaran, κ-carrageenan, ι-carrageenan and a κ/λ-carrageenan — structure, molecular weight and gel rheology was studied. Compared with other carrageenans, commercial furcellaran that had undergone multiple heatings at high temperatures during production was found to be susceptible to polymer degradation. Heat caused the desulphation and degradation of furcellaran galactans and the molecular weight was significantly decreased, causing a drop in viscosity and gel hardness. The loss of the network cross-linking of furcellaran gels was confirmed by scanning electron microscopy. Carrageenan gel storage modulus values decreased with the increase in the temperature of the treatment. The greatest decrease in storage modulus values occurred with κ/λ-carrageenan gels, followed by ι-carrageenan > furcellaran > κ-carrageenan., Carrageenan; NMR; Molecular weight; Rheology
- Published
- 2021
21. Structure of a bacterial ice binding protein with two faces of interaction with ice
- Author
-
Marco Nardini, Marco Mangiagalli, Vittoria Federica Vena, Aleksei Kaleda, Maya Bar Dolev, Guy Sarusi, Ido Braslavsky, Valentina Nardone, Marina Lotti, Mangiagalli, M, Sarusi, G, Kaleda, A, Bar Dolev, M, Nardone, V, Vena, V, Braslavsky, I, Lotti, M, and Nardini, M
- Subjects
0301 basic medicine ,Models, Molecular ,Protein Folding ,Protein Conformation ,Amino Acid Motifs ,FIS/07 - FISICA APPLICATA (A BENI CULTURALI, AMBIENTALI, BIOLOGIA E MEDICINA) ,Euplotes ,Sequence alignment ,Ice recrystallization inhibition ,Plasma protein binding ,Crystallography, X-Ray ,Biochemistry ,Thermal hysteresi ,DUF3494 ,03 medical and health sciences ,Protein structure ,Bacterial Proteins ,Antifreeze protein ,Amino Acid Sequence ,Molecular Biology ,030102 biochemistry & molecular biology ,Ice crystals ,Sequence Homology, Amino Acid ,Chemistry ,Cold adaptation ,Ice ,computer.file_format ,Cell Biology ,Protein Data Bank ,BIO/10 - BIOCHIMICA ,Recombinant Proteins ,Molecular Docking Simulation ,Crystallography ,030104 developmental biology ,Ice binding ,IBP-1 fold ,Mutagenesis, Site-Directed ,Protein folding ,Crystallization ,computer ,Sequence Alignment ,Protein Binding - Abstract
Ice-binding proteins (IBPs) contribute to the survival of many living beings at subzero temperature by controlling the formation and growth of ice crystals. This work investigates the structural basis of the ice-binding properties of EfcIBP, obtained from Antarctic bacteria. EfcIBP is endowed with a unique combination of thermal hysteresis and ice recrystallization inhibition activity. The three-dimensional structure, solved at 0.84 A resolution, shows that EfcIBP belongs to the IBP-1 fold family, and is organized in a right-handed β-solenoid with a triangular cross-section that forms three protein surfaces, named A, B, and C faces. However, EfcIBP diverges from other IBP-1 fold proteins in relevant structural features including the lack of a 'capping' region on top of the β-solenoid, and in the sequence and organization of the regions exposed to ice that, in EfcIBP, reveal the presence of threonine-rich ice-binding motifs. Docking experiments and site-directed mutagenesis pinpoint that EfcIBP binds ice crystals not only via its B face, as common to other IBPs, but also via ice-binding sites on the C face. Database Coordinates and structure factors have been deposited in the Protein Data Bank under accession number 6EIO.
- Published
- 2018
- Full Text
- View/download PDF
22. Identification and functional analysis of a novel Antarctic ice binding protein
- Author
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Ido Braslavsky, Maya Bar-Dolev, Donatella De Pascale, Marco Mangiagalli, Marina Lotti, Sandra Pucciarelli, Aleksei Kaleda, Antonino Natalello, and Stefania Brocca
- Subjects
Ice binding ,Functional analysis ,Chemistry ,Bioengineering ,Identification (biology) ,General Medicine ,Computational biology ,Molecular Biology ,Ice binding protein ,Biotechnology - Abstract
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- Published
- 2016
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