Screening of lactases suitable for the preparation of low-lactose prebiotic liquid milk and optimisation of their combination

Abstract Lactose intolerance is an important factor restricting the consumption of dairy products. Lactase is used to hydrolyze lactose in milk while generating galactooligosaccharides (GOS), thereby reducing the incidence of lactose intolerance. We used cow milk as raw materials, and selected enzyme preparations with high lactose hydrolysis rate and strong GOS generation ability from 14 commercially available lactase enzymes. The lactose hydrolysis rate is 5.85%-81.38%, and the GOS content is 0.03 g/L- 13.10 g/L. The mixing experiment design determined the two lactase enzymes (E10 and E11) ratio and the optimal enzymatic hydrolysis process of low-lactose prebiotic milk: compound lactases (E10:E11=0.756:0.244) addition 0.11%, 55℃for 5h, lactose hydrolysis rate and GOS content were 98.02% and 19.69g/L, respectively, and the remaining lactose content was about 0.97 g/L.

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Valorization of Greenhouse Horticulture Waste from a Biorefinery Perspective

Foods ◽

10.3390/foods10040814 ◽

2021 ◽

Vol 10 (4) ◽

pp. 814

Author(s):

Antonio D. Moreno ◽

Aleta Duque ◽

Alberto González ◽

Ignacio Ballesteros ◽

María José Negro

Keyword(s):

Enzymatic Hydrolysis ◽

Raw Materials ◽

Reactive Extrusion ◽

Extrusion Process ◽

Alkali Concentration ◽

Hydrolysis Process ◽

Twin Screw ◽

Greenhouse Horticulture ◽

Extrusion Technology ◽

Sugar Source

Greenhouse cultivation and harvesting generate considerable amounts of organic waste, including vegetal waste from plants and discarded products. This study evaluated the residues derived from tomato cultivation practices in Almería (Spain) as sugar-rich raw materials for biorefineries. First, lignocellulose-based residues were subjected to an alkali-catalyzed extrusion process in a twin-screw extruder (100 °C and 6–12% (w/w) NaOH) to assess maximum sugar recovery during the subsequent enzymatic hydrolysis step. A high saccharification yield was reached when using an alkali concentration of 12% (w/w), releasing up to 81% of the initial glucan. Second, the discarded tomato residue was crushed and centrifuged to collect both the juice and the pulp fractions. The juice contained 39.4 g of sugars per 100 g of dry culled tomato, while the pulp yielded an extra 9.1 g of sugars per 100 g of dry culled tomato after an enzymatic hydrolysis process. The results presented herein show the potential of using horticulture waste as an attractive sugar source for biorefineries, including lignocellulose-based residues when effective fractionation processes, such as reactive extrusion technology, are available.

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Süt Kaynaklı Olmayan Probiyotik Gıdalar

Turkish Journal of Agriculture - Food Science and Technology ◽

10.24925/turjaf.v5i12.1615-1625.1449 ◽

2017 ◽

Vol 5 (12) ◽

pp. 1615 ◽

Cited By ~ 2

Author(s):

Ali Soyuçok ◽

Gülden Başyiğit Kılıç

Keyword(s):

Dairy Products ◽

Fruits And Vegetables ◽

Lactose Intolerance ◽

Raw Materials ◽

Meat Products ◽

Cholesterol Content ◽

Fermented Milk ◽

Research Priority ◽

Dairy Consumption ◽

Food Design

Probiotic products available in the markets today, are usually in the form of fermented milk products. Dairy consumption have been limited by lactose intolerance and the cholesterol content in dairy products. Besides, traditions and economic reasons that limit the use of dairy fermented products in some developing countries promote the idea of using of alternative raw materials as vehicles for the probiotic agents. For these reasons meat products, cereals, legumes, fruits and vegetables may be potential substrates, where the healthy probiotic bacteria will make their mark, amongst consumers. To develop of these products is a key research priority for food design and a challenge for both industry and science sectors. In this study, information’s were given about non-dairy probiotic foods and highlighting the researches done in this field.

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Distribution of the Emetic Toxin Cereulide in Cow Milk

Toxins ◽

10.3390/toxins13080528 ◽

2021 ◽

Vol 13 (8) ◽

pp. 528

Author(s):

Veronika Walser ◽

Markus Kranzler ◽

Corinna Dawid ◽

Monika Ehling-Schulz ◽

Timo D. Stark ◽

...

Keyword(s):

Milk Fat ◽

Dairy Products ◽

Raw Materials ◽

Cow Milk ◽

Lipid Phase ◽

Processed Foods ◽

Cross Contamination ◽

Hydrophobic Properties ◽

Food Borne ◽

Hydrophobic Lipid

Bacillus cereus is frequently associated with food-borne intoxications, and its emetic toxin cereulide causes emesis and nausea after consumption of contaminated foods. The major source for contamination is found within contaminated raw materials containing the highly chemically resistant cereulide, independent of vegetative bacteria cells. Up to date, non-existing removal strategies for cereulide evoke the question of how the toxin is distributed within a food sample, especially cow milk. Milk samples with different milk fat contents were incubated with purified cereulide, separated by centrifugation into a lipid and an aqueous phase, and cereulide was quantified in both fractions by SIDA-LC-MS/MS. By artificially increasing the milk fat content from 0.5% to 50%, the amount of cereulide recovered in the lipid phase and could be augmented from 13.3 to 78.6%. Further, the ratio of cereulide increased in the lipid phase of milk with additional plant-based lipid (sunflower oil) to 47.8%. This demonstrated a clear affinity of cereulide towards the hydrophobic, lipid phase, aligning with cereulide’s naturally strong hydrophobic properties. Therefore, an intensified cereulide analysis of lipid enriched dairy products to prevent severe cereulide intoxications or cross-contamination in processed foods is suggested.

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Study on the Kinetics of Salmon Skin Proteolysis

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2019.3054 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1706-1710

Author(s):

Yiping Xia ◽

Hao Yu ◽

Yaoguang Zhong

Keyword(s):

Enzymatic Hydrolysis ◽

Kinetic Model ◽

Kinetic Mechanism ◽

Reaction Rate Constant ◽

Hydrolysis Rate ◽

Degree Of Hydrolysis ◽

Hydrolysis Process ◽

Skin Protein ◽

Kinetics Of ◽

Hydrolysis Of

In this study, in order to study the kinetic mechanism of enzymatic hydrolysis of salmon protein, the kinetic model of enzymatic hydrolysis of salmon skin protein by papain was established. The skin protein of salmon was hydrolyzed by papain under the following conditions: the mass concentration of salmon skin protein is 55 g/L, the initial papain concentration is 2.0 g/L, the pH of enzymatic solution is 7.2 and the temperature of enzymatic hydrolysis is 55 °C. Finally, the kinetic model of hydrolysis was established as follows: Hydrolysis rate R =(27.217E0–0 0357S0exp[–0.2587(DH)]; Degree of hydrolysis DH = 3.879 ln[1 + 7.0165E0/S0 –0.0092t]. The reaction rate constant k3 = 27.217 min–1 and the enzyme deactivation constant kd = 7.0752 min–1 were deduced to control the enzymatic hydrolysis process. Further verification tests showed that the theoretical value of the degree of hydrolysis of the model was basically consistent with the actual value, and the kinetic model had certain practical value, indicating that the established salmon skin protease kinetic model could be used to guide and optimize the enzymatic hydrolysis process.

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Development of a Digital Twin for Enzymatic Hydrolysis Processes

Processes ◽

10.3390/pr9101734 ◽

2021 ◽

Vol 9 (10) ◽

pp. 1734

Author(s):

Christian Appl ◽

Frank Baganz ◽

Volker C. Hass

Keyword(s):

Enzymatic Hydrolysis ◽

Raw Materials ◽

Starch Hydrolysis ◽

Strategy Development ◽

Enzymatic Process ◽

Nutrient Media ◽

Renewable Raw Materials ◽

Digital Twins ◽

Hydrolysis Process ◽

Kinetics Of

Enzymatic hydrolysis processes can be used to produce organic nutrient media from renewable raw materials. However, many of these processes are not optimally designed, so expensive enzymes and substrates are wasted. Mathematical models and Digital Twins (DTs) are powerful tools, which can be used to optimize bioprocesses and, thus, increase the yield of the desired products. Individual enzymatic hydrolysis processes have already been modeled, but models for the combined starch hydrolysis and proteolysis, or DTs, are not available yet. Therefore, an easily adaptable, dynamic, and mechanistic mathematical model representing the kinetics of the enzymatic hydrolysis process of the combined starch hydrolysis and proteolysis was developed and parameterized using experimental data. The model can simulate the starch hydrolysis process with an agreement of over 90% and the proteolysis process with an agreement of over 85%. Subsequently, this model was implemented into an existing DT of a 20 L stirred tank reactor (STR). Since the DT cannot only map the kinetics of the enzymatic process, but also the STR with the associated periphery (pumps, heating jacket, etc.), it is ideally suited for future process control strategy development and thus for the optimization of enzymatic hydrolysis processes.

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FERMENTATIVE HYDROLYTIC PREPARATION METHODS OF CEREAL WORT FOR ALCOHOL FERMENTATION

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2020/5/52-56 ◽

1970 ◽

pp. 52-56

Author(s):

Е. M. Serba ◽

М. B. Overchenko ◽

L. V. Rimareva ◽

N. I. Ignatova ◽

А. E. Orekhova ◽

...

Keyword(s):

Alcoholic Fermentation ◽

Raw Materials ◽

Alcohol Concentration ◽

Activity Level ◽

Optimal Dosage ◽

Main Role ◽

Alcohol Fermentation ◽

Ph Optimum ◽

Amylolytic Enzyme ◽

Enzyme Preparations

In the production of alcohol in the preparation of grain raw materials for fermentation, the main role is given to enzyme preparations of amylolytic action, which are key enzymes that catalyze the hydrolysis of starch. Amylolytic enzyme preparations with a different composition of enzymes and their level of activity, a mechanism of biocatalytic effect on starch, and a range of thermal and pH optimum are widely represented on the Russian market. The development of optimal conditions for the preparation of grain wort, the rational selection and dosage of concentrated enzyme preparations, the properties of which correspond to the parameters of the technological process, will ensure the effective preparation of starch for fermentation, and increase the profitability of alcohol production. The aim of this work was to study the influence of enzyme preparations of amylolytic action and the conditions of their use on the efficiency of the process of alcoholic fermentation and the yield of the final product, ethanol. The effect of various dosages of enzyme preparations of glucoamylase action, with a different ratio of the main enzyme glucoamylase and minor enzyme α-amylase, as well as methods for preparing wheat wort on the process of alcoholic fermentation, was studied. It was found that the enzyme preparation, the source of glucoamylase, in which α-amylase was present in a ratio of 15: 1 (in terms of activity level), turned out to be more effective in fermenting prepared wheat wort: its optimal dosage was 8 units. GLS / g starch. The presence of a sufficient amount of α-amylase in this preparation compensated for the dosage of thermostable α-amylase. The alcohol concentration in the mash was 10.2% vol., The alcohol yield was 67.9 cm3 / 100 g of starch. When glucoamylase with a lower ratio of the main and minor enzyme (75: 1) was used at the saccharification stage, an increase in the wort fermentation depth was observed with an increase in the concentration of glucoamylase to 9-10 units of GLS / g and α-amylase to 0.5 units. AC / g. It was also found that an increase in the duration of enzymatic-hydrolytic preparation of the wort had a positive effect on the fermentation process, the alcohol concentration in the mash increased to 10.2 vol.%. It was shown that the introduction of proteases into the wort helps to reduce the viscosity of grain wort, enriching it with assimilable yeast amino acids, which leads to an increase in the yield of alcohol. It has been confirmed that the synergy of the action of enzymes of amylolytic and proteolytic effects on polymers of grain raw materials allows to increase the efficiency of their conversion to ethanol. The conditions of enzymatic-hydrolytic processing of grain raw materials for fermentation are developed. The use of the digestion stage did not significantly affect the fermentation results of wheat wort.

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ADAPTATION AND DEVELOPMENT OF MILK PRODUCERS IN THE NEW ECONOMIC CONDITIONS

Molochnoe i miasnoe skotovodstvo ◽

10.33943/mms.2020.37.77.001 ◽

2020 ◽

Author(s):

В.Н. СУРОВЦЕВ ◽

Е.Н. ПАЮРОВА

Keyword(s):

Dairy Products ◽

Raw Materials ◽

Raw Milk ◽

World Market ◽

Food Prices ◽

Economic Conditions ◽

State Support ◽

Demand Reduction ◽

The World ◽

Dairy Cattle Breeding

Проанализированы проблемы на рынке молока и молочных продуктов России в условиях глобального экономического кризиса: перепроизводство молока в основных странах-экспортерах, снижение закупочных цен на сырое молоко, снижение цен на биржевые товары в мире и России в 2020 году, тренд на уменьшение спроса на молочные продукты на мировом рынке в среднесрочном периоде, снижение общего спроса на молочные продукты на внутрироссийском рынке при падении реальных доходов населения, изменение структуры потребления. Проведена оценка новых возможностей и угроз для развития отрасли: со стороны потребителей — рост цен на продовольствие, снижение доходов; с позиции производителей молока — снижение закупочных цен, рост требований к сырью для производства продукции с увеличенными сроками годности, дефицит рабочей силы, вероятное сокращение господдержки в результате снижения цен на углеводороды, попытки регулирования цен; со стороны перерабатывающих предприятий — сокращение спроса, снижение цен на готовую продукцию вслед за мировыми ценами. Обоснованы приоритеты инвестирования в молочном скотоводстве и основные формы совершенствования государственной поддержки отрасли, обеспечивающие эффективную адаптацию производителей молока к новым экономическим условиям, повышение устойчивости отрасли при усилении макроэкономических рисков. The article analyzes the problems in the Russian milk and dairy products market in the context of the global economic crisis: overproduction of milk in the main exporting countries, lower purchase prices for raw milk, lower prices for commodities in the world and in Russia in 2020, trend to reduce demand for dairy products on the world market in medium term, a decrease in total demand for dairy products in the Russian market with a decrease in the purchasing power of the population, a change in the structure of consumption. An assessment of new opportunities and threats to the development of the industry was carried out: on the part of consumers — rising food prices, lower incomes; from the perspective of dairy producers — reduction in purchase prices, increased requirements for raw materials for the production of products with extended periods, labor shortages, the likely reduction in state support as a result of lower prices for hydrocarbons, attempts to regulate prices; on the part of processing enterprises — reduction of demand, reduction of prices for finished goods following world prices. The investment priorities in dairy cattle breeding and the main forms of improving state support for the industry, ensuring the effective adaptation of milk producers to new economic conditions, increasing the sustainability of the industry with increasing macroeconomic risks, are substantiated.

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Improvement of Enzymatic Saccharification of Cellulose-Containing Raw Materials Using Aspergillus niger

Processes ◽

10.3390/pr9081360 ◽

2021 ◽

Vol 9 (8) ◽

pp. 1360

Author(s):

Ekaterina Budenkova ◽

Stanislav Sukhikh ◽

Svetlana Ivanova ◽

Olga Babich ◽

Vyacheslav Dolganyuk ◽

...

Keyword(s):

Enzymatic Hydrolysis ◽

Aspergillus Niger ◽

Filter Paper ◽

Raw Materials ◽

Enzymatic Saccharification ◽

Wood Chip ◽

Cellulase Activity ◽

Wood Chips ◽

Acid Pretreatment ◽

Hydrolysis Of

Enzymatic hydrolysis of cellulose-containing raw materials, using Aspergillus niger, were studied. Filter paper, secondary cellulose-containing or starch-containing raw materials, miscanthus cellulose after alkaline or acid pretreatment, and wood chip cellulose, were used as substrates. The study focused on a wild A. niger strain, treated, or not (control), by ultraviolet (UV) irradiations for 45, 60, or 120 min (UV45, UV60, or UV120), or by UV irradiation for 120 min followed by a chemical treatment with NaN3 + ItBr for 30 min or 80 min (UV120 + CH30 or UV120 + CH80). A mixture of all the A. niger strains (MIX) was also tested. A citrate buffer, at 50 mM, wasthe most suitable for enzymatic hydrolysis. As the UV exposure time increased to 2 h, the cellulase activity of the surviving culturewas increased (r = 0.706; p < 0.05). The enzymatic activities of the obtained strains, towards miscanthus cellulose, wood chips, and filter paper, were inferior to those obtained with commercial enzymes (8.6 versus 9.1 IU), in some cases. Under stationary hydrolysis at 37 °C, pH = 4.7, the enzymatic activity of A. niger UV120 + CH30 was 24.9 IU. The enzymatic hydrolysis of secondary raw materials, using treated A. niger strains, was themost effective at 37 °C. Similarly, the most effective treatment of miscanthus cellulose and wood chips occurred at 50 °C. The maximum conversion of cellulose to glucose was observed using miscanthus cellulose (with alkaline pretreatment), and the minimum conversion was observed when using wood chips. The greatest value of cellulase activity was evidenced in the starch-containing raw materials, indicating that A. niger can ferment not only through cellulase activity, but also via an amylolytic one.

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Enzymatic textile recycling – best practices and outlook

Waste Management & Research ◽

10.1177/0734242x211029167 ◽

2021 ◽

pp. 0734242X2110291

Author(s):

Benjamin Piribauer ◽

Andreas Bartl ◽

Wolfgang Ipsmiller

Keyword(s):

Enzymatic Hydrolysis ◽

Complete Removal ◽

The European Union ◽

Textile Processing ◽

Current State ◽

Industrial Implementation ◽

Hydrolysis Process ◽

Textile Recycling ◽

Textile Sector ◽

Suitable Process

Recently, textiles and their end-of-life management have become the focus of public and political attention. In the European Union the revised waste framework directive defines textiles as municipal waste and stipulates their separate collection by 2025. In the context of these developments, this paper summarises briefly the current state-of-the-art in textile recycling. It is evident that recycling methods are not yet fully developed. This is especially the case with multi-material textiles, which are composed of two or more polymers that are incompatible for recycling. In the practical part of the communication, results are presented which show that enzymatic hydrolysis is a suitable process for recycling textiles made of cotton and polyester. After a complete removal of cotton, the remaining pure polyester fibres undergo a re-granulation and post-condensation step. The so obtained recycled polyester is fed back into the textile processing chain and finally towels are obtained. The main steering parameters of the enzymatic hydrolysis process are described. The study proves that solutions in accordance with the Circular Economy in the textile sector are available but an industrial implementation has not yet been realised.

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