Enzymatic Hydrolysis Of Lactose Research Articles

Decreasing Sugar Level by Enzymatic Hydrolysis of Lactose in Fruit Yogurt

Decreasing Sugar Level by Enzymatic Hydrolysis of Lactose in Fruit Yogurt

The quality indicators of ice cream upon the enzymatic hydrolysis of lactose

Ice cream is a popular type of dairy foods containing up to 6% of lactose. In connection with the lactose intolerance by many consumers and the possibility of its crystallization during storage of finished products, there is a need for a decrease in the content of this nutrient in the composition of ice cream. The aim of the research was to study an effect of the lactose hydrolysis process in ice cream with the fat mass fraction of 15% and different mass fractions of dry skim milk residue on technologically significant and sensory properties of its quality. The main objects of the study were samples of ice cream subjected to lactose hydrolysis at the stage of mixture maturation. The fat mass fraction in the samples was 15%, mass fractions of dry skim milk residue were 7, 10, 12 and 15%. The composition of sugars was determined by high-performance liquid chromatography, the dynamic viscosity of mixes and the consistency of ice cream by rheological methods and the dispersion of structural elements by microcopy. The effects of the mass fraction of dry skim milk residue and lactose hydrolysis on quality indicators of mixtures and ice cream were determined. As the mass fraction of dry skim milk residue rose from 7 to 15%, the residual content of lactose increased from 0.2 to 1.1%, while the dynamic viscosity of the mixture increased by 1.3 times. A decrease in the freezing point by 0.6–0.8 °C and an increase in melting resistance were also observed. The mass fraction of melt after 2 hours of holding decreased to 4.7–0.7%. Also, indicators of consistency (hardness, adhesiveness, adhesion force and rigidity) decreased by 1.1–1.7 times (upon a mass fraction of dry skim milk residue of 7 and 10%). The samples of ice cream subjected to lactose hydrolysis were characterized by a high dispersion of structural elements typical for a traditional product, and by improved texture and increased sensation of sweetness. The complex of investigations to study quality indicators of ice cream with the fat mass fraction of 15% showed that a change in the mass fraction of dry skim milk residue upon enzymatic hydrolysis of lactose results in formation of different structural-mechanical and sensory indicators that should be considered during the creation of assortment and development of formulations of low-lactose products.

Study of UF-retentate concentration degree in low- and lactose-free products’ development

The article provides a comparative evaluation of some organoleptic characteristics of low- and lactose-free milk samples produced on the basis of ultrafiltration concentrates of skim milk with different mass fraction of solids. Using the ranking method, it was found that the sample produced on the basis of UV concentrate with a mass fraction of solids of 27 % followed by enzymatic hydrolysis of lactose has the best indices of taste and sweetness. The results obtained were necessary for the development of the recipe and technology for the production of low- and lactose-free milk.

Canned dairy: factors of increasing preservation

Introduction. The main criterion for the state of water in food is the indicator of "water activity" (Aw), which affects their quality and shelf life. Problem. At present, it is advisable to propose such changes in the recipe and technology of canned milk, which would reduce the rate of "water activity" and increase the osmotic pressure. The aim of the work is scientific substantiation of factors of canned milk preservation. Methods. Objects of scientific research – low-fat condensed low-lactose milk with a sugar content of 13, 16 and 31 %, the low-fat condensed milk with sugar by traditional technology was used as a control; dry milk multicomponent mixture with the addition of dry whey protein concentrate, as a control there was selected milk-carbohydrate mixture without protein component. Water activity (Aw) was determined on the device AguaLab-3TE, osmotic pressure – by cryoscopic method. The number of mesophilic aerobic and facultative anaerobic microorganisms was determined according to DSTU ISO 4833: 2006. Results. Samples of low-lactose condensed milk with mass fraction of 34 and 32 % and sugar content of 31 % in terms of osmotic pressure and "water activity" were the closest to traditional condensed milk with sugar and complied with current regulations on microbiological indicators. The dry whey protein concentrate, included into the formula of the dry milk multicomponent mixture, acts as a water-binding component, reducing the "water activity" to 0.290. Conclusions. The use of enzymatic hydrolysis of lactose with the use of the enzyme preparation β-galactosidase has a positive effect on the osmotic pressure and the indicator of "water activity". In the dry milk multicomponent mixture, the proposed dry whey protein concentrate as a water-binding component helps to reduce the rate of "water activity" and the number of microorganisms. The proposed changes in the technology and recipe of the investigated canned milk will allow to extend the shelf life of products.

Artificial intelligence applied to enzymatic hydrolysis of lactose: improving the control of industrial processes

Lactose is the main carbohydrate in milk, and its absorption occurs via enzymatic hydrolysis, generating glucose and galactose. Lactose intolerance is the reduction of intestinal hydrolysis capacity due to hypolactasia, which results in the need to consume dairy foods with low levels of this carbohydrate. β-galactosidase enzymes are used in dairy industries to hydrolyze lactose, thereby allowing intolerant consumers access to dairy products without the negative health implications. Alternative and official analytical methods are used to quantify the carbohydrate content resulting from enzymatic hydrolysis. The objective of this study was to evaluate the enzymatic hydrolysis of two distinct industrial enzymes produced by the microorganisms Bacillus licheniformis and Kluyveromyces lactis using three analytical methods: enzymatic method, cryoscopy, and high performance liquid chromatography (HPLC) using artificial intelligence to improve the control of the industrial processes. After adding the enzymes to skim milk, time kinetics was performed by collecting samples at time 0, every 10 min for 1 h, and every 30 min until the end of 5 h of hydrolysis. In 97% of the cases, a decrease in lactose concentration was observed by HPLC, followed by the deepening of the cryoscopic point. Glucose measurements by absorbance and HPLC quantification were correlated (r = 0.79; p < 0.01) but not concordant (p < 0.01). It was concluded that by means of artificial intelligence, it was possible to indirectly estimate lactose concentration using an algorithm that associates cryoscopy and glucose concentration.

Lactose hydrolysis implications on dairy beverages with autochthonous Limosilactobacillus mucosae and Syzygium cumini pulp

The effects of enzymatic hydrolysis of lactose on the acidification, composition, microbial viability, sensory characteristics and antioxidant capacity of a dairy beverage fermented with potentially probiotic Limosilactobacillus mucosae CNPC007 in co-culture with Streptococcus thermophilus, and flavored with Syzygium cumini (L.) Skeels (jambolan) pulp were investigated during 21 days of refrigerated storage (4 ± 1 °C). The lactose-free trial showed faster acidification during the fermentative process, post-acidification during the storage, slightly lower overall acceptability and anticipated reduction in L. mucosae viability, although remaining above 6.50 log cfu/g at the end of storage. No differences were verified between control and lactose-free dairy beverages in relation to the total phenolic content, DPPH radicals scavenging and EC50. Jambolan pulp did not affect L. mucosae viability and enhanced by two-fold the parameters of antioxidant capacity in both control and lactose-free beverages in comparison with their respective dairy bases without addition of fruit. Despite the changes caused by lactose hydrolysis on the metabolism of lactic cultures, the addition of jambolan pulp improved the functional potential of the lactose-free dairy beverage with L. mucosae CNPC007.

Lactose-free Dulce de leche: compositional characterization, browning and texture profile.

Our objective was to elaborate lactose-free Dulce de leche (DL) and evaluate the influence of the hydrolysis of this sugar on the attributes of the products. Fluid milk used was divided into two portions and, in one of them, enzymatic hydrolysis of lactose was carried through. Next, the homogenization of milk was performed at 20 MPa. Four different treatments were studied. The final products were evaluated in relation to their composition and physico-chemical characteristics. The main results show that the homogenized lactose-free DL obtained a higher concentration of free 5-Hydroxymethylfurfural (HMF) (133.77 ± 3.42 μmol l-1). Consequently, browning was more intense due to Maillard Reaction. Texture parameters were higher (1611.00 ± 598.78 g hardness and 19.52 ± 2.46 g gumminess) when compared to the homogenized traditional product (28.45 ± 1.16 μmol l-1 free HMF, 437.17 ± 279.3 g hardness, and 406.20 ± 311.69 g gumminess). Lactose-free products are in high demand by consumers; however, the results of this work highlight the challenges to properly control the browning and the texture parameters of DL.

Whey: State of the Art. Part II. Processes and Treatment Methods

The current state of the art on studying of whey is considered. The processes and methods of whey processing (thermal, chemical, physicochemical, biotechnological, and electrophysical) are presented. Thermal and isoelectric precipitation of proteins, using reagents and coagulants, as well as the main membrane processing methods (reverse osmosis, diafiltration, microfiltration, ultrafiltration, and nanofiltration) are described. Possibi-lities of effective separation of whey proteins by a combination of membrane and other methods are noted. Chromatographic methods for fractionation of whey proteins (chromatography with imitation of a moving bed, high-gradient chromatography with a magnetic trap, selective adsorption, displacement chromatography, membrane adsorption), which provide a high degree of separation, are described. Highly porous chromatographic materials providing a high flow rate, biotechnological processing methods – biosynthesis of lactulose, enzymatic hydrolysis of lactose and whey proteins, aerobic and anaerobic fermentation are considered. Electrophysical methods of processing whey (electrodialysis, electroactivation), which include electrodialysis and electro-activation, as well as electrochemical activation as a phenomenon and technology, as a new promising processing method that allows to create a waste-free cycle for obtaining valuable components and useful derivatives from whey without the use of reagents are analyzed. It is emphasized that, depending on the regimes used, protein-mineral concentrates with a predetermined protein or mineral composition are obtained with the simultaneous isomerization of lactose into lactulose. It is stated that the efficiency of methods for processing whey is ensured by a significant increase in the efficiency of technological processes, a decrease in labor costs, a reduction in the processing time and materials, and an improvement in the quality and functional properties of the final products.

Enzymatic hydrolysis of lactose in concentrates of reconstituted demineralized whey, intended for ice cream production

Enzymatic hydrolysis of lactose in concentrates of reconstituted demineralized whey, intended for ice cream production

Effect of Temperature, pH and Amount of Enzyme Used in the Lactose Hydrolysis of Milk

Lactose intolerance is becoming a health state that requires the restriction of dairy products in the diet of people suffering from this condition. But milk and dairy products, due to a well-balanced composition in the main macro and micronutrients, cannot be missing from the diet of the consumer of any age. For these reasons, in recent years, in the milk processing industry, the production of low-lactose or lactose-free dairy products is explored. To reduce the lactose content of dairy raw materials, various industrial and biotechnological methods were used: enzymatic hydrolysis of lactose, baromembranous methods, bioconversion of lactose by lactic bacteria and others. The most widely used lactase enzymes in the industry are mesophilic enzymes from filamentous fungi (Aspergillus spp.) and yeasts (Kluyveromyces spp.). Therefore, the aim of this study was to evaluate the effect of the commercial enzyme β-galactosidase on the hydrolysis of cow’s milk at different enzyme concentrations, temperatures and pH. Two commercial enzymes β-galactosidase obtained from Bacillus licheniformis and β-galactosidase obtained from Kluyveromyces lactis, were used in this study, according to information provided by the manufacturer. The thermal stability of lactose, the effect of milk pH, the effect of temperature, duration of hydrolysis and the amount of enzymes on the lactose hydrolysis degree and the sweetness degree of milk were determined. Research has identified the optimal parameters for obtaining a high degree of lactose hydrolysis in the use of these enzymes. Therefore, to ensure a high lactose hydrolysis degree (over 80%), the following lactose hydrolysis regimens were identified: temperature 4&degC - 6&degC, 0.3% Bacillus licheniformis enzymes, duration 4 hours; temperature 4&degC - 6&degC, 0.3% enzymes from Klavyromyces lactis, duration 12 hours and temperature 38&degC - 40&degC, 0.15% enzymes from (Bacillus licheniformis or Klavyromyces lactis), duration 2 - 3 hours. The results obtained allow the efficient use of Bacillus licheniformis and Klavyromyces lactis enzymes in industrial processes for the manufacture of “lactose-free” or “low-lactose” drinking milk and fermented dairy products for people with lactose intolerance.

INTENSIFICATION OF THE MELANOIDIN FORMATION REACTION IN THE PRODUCTION OF SWEET BOILED CANNED MILK

The article gives empirical grounding of reducing the melanoidins formation process duration at high-temperature processing of sweet canned milk due to the use of enzymatic hydrolysis of lactose. In sweet canned milk samples with hydrolyzed lactose there was a more intensive decrease in active acidity and an increase in oxidation-reduction potential and obviously a change in milk color within a short period of time by contrast to milk with not hydrolyzed lactose. Lactose disaccharide splitting to (38±2)% allows to reduce the duration of high-temperature processing average by 40% at
 traditionally applied prossing temperature of (105±5) °C, and reduce the sucrose content in the finished product by 3–8%. The use of fructose in order to accelerate the process of cooking whole condensed milk is not rational.

Assessment of enzymatic hydrolysis of lactose in lactose-free milk production - A comparative study using capillary zone electrophoresis and cryoscopy

A comparison of the capillary zone electrophoresis under indirect detection at ultraviolet region (CZE-UV) method with the traditional cryoscopic method for lactose hydrolysis process monitoring is proposed. Two different lactose enzymatic hydrolysis processes (in batch and sterile) were assessed. The hydrolysis levels obtained by the CZE-UV method differed statistically from those obtained by cryoscopy, at 95% confidence, showing variations up to 20% at the same time of processing. During sterile hydrolysis, 90% of lactose reduction was detected after 1 h by CZE-UV and after 3 h by cryoscopy. For in batch hydrolysis, the CZE-UV method indicated 50% of lactose hydrolysis after 3 h of processing, while the cryoscopic method did not identify such lactose reduction during the process simulation. Our results demonstrated that CZE-UV method is precise and reliable analytical method, acting as a good alternative for lactose hydrolysis process monitoring.

Effects of enzymatic lactose hydrolysis on thermal markers in lactose-free UHT milk.

Lactose-free products are more susceptible to chemical and physical modifications during heating and storage, due to the release of glucose and galactose during enzymatic processing, both more reactive than lactose. The present study demonstrates the effect of enzymatic lactose hydrolysis on 5-hydroxymethylfurfural (HMF), whey protein nitrogen index (WPNI) and lactulose used as thermal markers for UHT milk process monitoring. Six milk leading brands which provided regular and lactose-free UHT milk were selected, giving a total of 12 UHT milk samples analyzed in authentic duplicates. All lactose-free samples showed high levels of HMF index (42.15µmol L-1, against 13.11µmol L-1 for regular samples) and low lactulose contents (13.03mg 100mL-1, against 35.59mg 100mL-1 of regular ones). High variations in HMF (55-85%) and lactulose (42-91%) intra-brand analysis indicated that both markers are influenced by the lactose hydrolysis process. The paired t test indicated there was no difference among WPNI indexes of regular and lactose-free milks suggesting that this thermal marker is suitable to infer about heat damage in lactose-free dairy matrices.

Osmolality and molar mass of oligosaccharides in breast milks and infant formula during hydrolysis of lactose. Application of high-resolution ultrasonic spectroscopy

β-Galactosidase formulations can be added to infant milks prior to feeding to reduce the level of lactose and to avoid symptoms of lactose intolerance. The hydrolysis of lactose affects osmolality, which is an important property of infant milk. This paper introduces novel ultrasonic technology for precision, real-time, non-destructive monitoring of osmolality of infant milks, including breast milk, during enzymatic hydrolysis of lactose by supplemental β-galactosidases. This technology can be utilised in the development and testing of β-galactosidase formulations. Additionally, ultrasonic real-time measurements of the average degree of polymerisation and molar mass of milk saccharides throughout the hydrolysis are discussed. Comparison of the ultrasonic results with discontinuous data of osmometry and HPLC showed an excellent agreement between the different techniques. The results elucidate the osmolality dynamics involved in the enzymatic hydrolysis of lactose in milks.

One-pot synthesis of sweetening syrup from lactose

Lactose has become the main byproduct of many dairy products and ingredients. Current applications of lactose are insufficient to use the recovered lactose from manufacturing operations. Here we exemplified a new process for converting aqueous lactose into a sweeting syrup via one-pot synthesis. The synthesis consisted of two-steps: (1) enzymatic hydrolysis of lactose and (2) catalytic isomerization over MgO/SiO2. The hydrolysis of lactose over β-galactosidase converted 95.77 ± 0.67% of lactose into glucose and galactose. The catalytic isomerization was performed over MgO/SiO2 with different MgO loadings (10–40 wt.%). A battery of tests was conducted to characterize the different catalysts, including surface properties, basicity, and microstructure. The one-pot synthesis, enzymatic hydrolysis and catalytic isomerization over 20%-MgO/SiO2, converted 99.3% of lactose into a sweetening syrup made of glucose (30.48%), galactose (33.51%), fructose (16.92%), D-tagatose (10.54%), and lactulose (3.62%). The outcomes of this research present an opportunity for expanding the utilization of lactose.

MILK WHEY PROCESSING: PROSPECTS IN UKRAINE

Milk processing not only makes the production of traditional dairy foods possible, but it is also followed by the formation of by-products, which are not fully utilized, and their emissions into wastewater worsen the environment. The modern technical and technological level of milk processing allows the full use of by-products, which are a source of whey proteins, lactose and other potentially useful ingredients at their base. Amid the decrease in milk production in recent years, an urgent problem is to increase the rank of milk processing in order to obtain products with high added value. The article presents the results of analytical studies of the state of the issue of whey processing in Ukraine. Modern conceptual approaches to solve the problems of processing various types of whey, which is formed as a by-product in the production of cheeses, cottage cheese, casein, are presented. The new types of products and ingredients obtained from whey, having a wide range of functional and technological properties and being in demand in the production of food products, are shown. The development trends of the novelty technologies for obtaining a wide range of whey-based products and ingredients are analyzed, new research data on their role in ensuring human health are presented. The review article reviews and justifies the feasibility of introducing modern membrane technologies for whey processing at domestic milk processing enterprises, this allowing rational use of raw milk resources, reducing negative environmental impact, and increasing production profitability. The results of scientific and applied research using membrane methods and enzymatic hydrolysis of lactose in technologies of dry demineralized whey and condensed low-lactose whey, are presented. The use of existing industrial equipment allows, due to changes in the protein-mineral composition of whey, obtaining products with a wide range of functional and technological properties and increased nutritional values.

Understanding the Effects of Lactose Hydrolysis Modeling on the Main Oligosaccharides in Goat Milk Whey Permeate.

Enzymatic hydrolysis of lactose is a crucial step to improve the efficiency and selectivity of membrane-based separations toward the recovery of milk oligosaccharides free from simple sugars. Response surface methodology was used to investigate the effects temperature (25.9 to 54.1 °C) and amount of enzyme (0.17 to 0.32% w/w) at 1, 2, and 4 h of reaction on the efficiency of lactose hydrolysis by Aspergillus oryzae β-galactosidase, preservation of major goat whey oligosaccharides, and on the de-novo formation of oligosaccharides. Lactose hydrolysis above 99% was achieved at 1, 2, and 4 h, not being significantly affected by temperature and amount of enzyme within the tested conditions. Formation of 4 Hexose (Hex) and 4 Hex 1 Hex and an increased de-novo formation of 2 Hex 1 N-Acetyl-Neuraminic Acid (NeuAc) and 2 Hex 1 N-Glycolylneuraminic acid (NeuGc) was observed in all treatments. Overall, processing conditions using temperatures ≤40 °C and enzyme concentration ≤0.25% resulted in higher preservation/formation of goat whey oligosaccharides.

Modeling of lactose enzymatic hydrolysis using Monte Carlo method

Abstract Background Mathematical modeling is useful in the analysis, prediction, and optimization of an enzymatic process. Unlike the conventional modeling methods, Monte Carlo method has special advantages in providing representations of the molecule’s spatial distribution. However, thus far, Monte Carlo modeling of enzymatic system is namely based on unimolecular basis, not suitable for practical applications. In this research, Monte Carlo modeling is performed for enzymatic hydrolysis of lactose for the purpose of real-time applications. Results The enzyme hydrolysis of lactose, which is conformed to Michaelis–Menten kinetics, is modeled using the Monte Carlo modeling method, and the simulation results prove that the model predicts the reaction kinetics very well. Conclusions Monte Carlo modeling method can be used to model enzymatic reactions in a simple way for real-time applications. How to cite: Gao L, Guo Q, Lin H, et al. Modeling of lactose enzymatic hydrolysis using Monte Carlo method. Electron J Biotechnol 2019;41. https://doi.org/10.1016/j.ejbt.2019.04.010

High-yield purification of commercial lactulose syrup

A simple process for purifying lactulose in commercial lactulose syrups was developed. The objective was to establish a selective enzymatic hydrolysis of lactose and epilactose and further removal of monosaccharides by activated charcoal and water/ethanol solutions. Four commercial β-galactosidases from different microorganisms were tested obtaining significant differences in their activities towards the three disaccharides present in the lactulose syrup. β-galactosidases from Bacillus circulans (Biolactasa® NTL*2) and Bifidobacterium bifidum (Saphera® 2600 L) showed a reduced enzymatic activity towards lactulose and a high enzymatic activity towards lactose. These two enzymes were chosen to optimize the lactose hydrolysis methodology using Response Surface Methodology (RSM). Once chosen the optimum enzymatic conditions to selectively hydrolyse lactose present in the lactulose syrup, the hydrolysed sample was treated with activated charcoal and water/ethanol solutions to eliminate all monosaccharides. The proposed method offers a product with high purity (>94%) and high recovery (>80%) of lactulose.

Development of Hypotonic Electrolyte Rehydration Drinks from Paneer and Cheese Whey

In the present study, development of electrolyte drinks from paneer and cheese whey was carried out by enzymatic hydrolysis of lactose to simple sugars and formulating the sugar to salt ratio to meet the World Health Organization (WHO) requirements (245 mOsmol/L) for Oral Rehydration Salt (ORS). Lactose hydrolyzed whey was diluted (1: 2.3 v/v) using potable quality demineralised water to achieve reduction in osmolarity of 75 mOsmol/L. The salt concentration was adjusted by adding 3.25 g sodium chloride and 0.8 g potassium chloride for paneer whey (per L) and 2.5 g sodium chloride, 0.9 g of potassium chloride and 1.5 g of trisodium citrate for cheese whey (per L) to meet Na, K and citrate levels in the resultant whey drink as per WHO requirement. Other additives used in developing hypotonic electrolyte whey drink from lactose hydrolyzed whey systems were sucralose (sweetener), citric acid (acidulant), orange flavour and orange colour. The formulated hypotonic electrolyte whey based drink had significantly higher sensory scores when compared to the scores of two commercial orange flavour ORS drinks. Cheese whey based electrolyte drink was superior over paneer whey based electrolyte drink in sensory characteristics; former drink had better consistency and mouth feel.