Technological aspects of lactose-hydrolyzed milk powder

The Utilisation of Mushroom Leftovers, Oats, and Lactose-Free Milk Powder for the Development of Geriatric Formulation

This study aims to focus on developing a food supplement for the geriatric population using disposal mushrooms, oats, and lactose-free milk powder. Lactose intolerance is most common in older adults, raising the demand for lactose-free foods. One of the major global challenges currently faced by humankind is food waste (FW). Most of the food that is produced for human consumption has not been utilized completely (1/3rd-1/2 unutilized), resulting in agricultural food waste. Mushrooms are highly valuable in terms of their nutritional value and medicinal properties; however, a significant percentage of mushroom leftovers are produced during mushroom production that do not meet retailers' standards (deformation of caps/stalks) and are left unattended. Oats are rich in dietary fibre beta-glucan (55% water soluble; 45% water insoluble). Lactose-free milk powder, oats, and dried mushroom leftover powder were blended in different ratios. It was observed that increasing the amount of mushroom leftover powder increases the protein content while diluting calories. The product with 15% mushroom powder and 30% oat powder showed the highest sensory scores and the lowest microbial count. The GCMS and FTIR analyses confirmed the presence of ergosterol and other functional groups. The results of the XRD analysis showed that the product with 15% mushroom powder and 30% oat powder had a less crystalline structure than the product with 5% mushroom powder and 40% oat powder and the product with 10% mushroom powder and 35% oat powder, resulting in more solubility. The ICP-OES analysis showed significant concentrations of calcium, potassium, magnesium, sodium, and zinc. The coliform count was nil for the products, and the bacterial count was below the limited range (3 × 102 cfu/g). The product with 15% mushroom powder and 30% oat powder showed the best results, so this developed product is recommended for older adults.

Reduction of maillard browning in spray dried low-lactose milk powders due to protein polysaccharide interactions

Lactose hydrolysed concentrated milk was prepared using β-galactosidase enzyme (4.76U/mL) with a reaction period of 12 h at 4 °C. Addition of polysaccharides (5 % maltodextrin/β-cyclodextrin) to concentrated milk either before or after lactose hydrolysis did not result in significant differences (p > 0.05) in degree of hydrolysis (% DH) of lactose and residual lactose content (%). Three different inlet temperatures (165 °C, 175 °C and 185 °C) were used for the preparation of powders which were later characterised based on physico-chemical and maillard browning characteristics. Moisture content, solubility and available lysine content of the powders decreased significantly, whereas, browning parameters i.e., browning index, 5-hydroxymethylfurfural, furosine content increased significantly (p < 0.05) with an increase in inlet air temperature. The powder was finally prepared with 5 % polysaccharide and an inlet air temperature of 185 °C which reduced maillard browning. Protein-polysaccharide interactions were identified using Fourier Transform infrared spectroscopy, fluorescence spectroscopy and determination of free amino groups in the powder samples. Maltodextrin and β-cyclodextrin containing powder samples exhibited lower free amino groups and higher degree of graft value as compared to control sample which indicated protein-polysaccharide interactions. Results obtained from Fourier Transform infrared spectroscopy also confirmed strong protein-polysaccharide interactions, moreover a significant decrease in fluorescence intensity was also observed in the powder samples. These interactions between the proteins and polysaccharides reduced the maillard browning in powders.

The effect of homogenisation pressure on the microstructure of milk during evaporation and drying: particle-size distribution, electronic scanning microscopy, water activity and isotherm

Homogenisation is a widely used technique in manufacturing powdered milk with a direct impact on product solubility, and the homogenisation pressure is a central attribute of this process. We aimed to understand the effect of increasing homogenisation pressures (0/0, 15/5, and 75/5 MPa, 1st/2nd stages) on particle-size distribution during homogenised whole milk powder manufacture and rehydration of the final product. The fluid milk was thermally treated, homogenised, concentrated by rotary evaporation, and then dried using a spray dryer. Particle size (Dv90) was monitored at all stages of the manufacturing process. The final product (milk powder) was analysed using particle-size distribution, electronic scanning microscopy, water activity, and isotherms. The results demonstrated that increasing the homogenisation pressure leads to milk powder with smaller particle size when rehydrated (Dv90 values: 6.08, 1.48 and 0.64 μm for 0, 20 and 80 MPa, respectively). Furthermore, the volume (%) of the particles in the 'sub-micro' region (smaller than 1.0 μm) presented an inversely proportional profile to the homogenisation pressure (homogenised fluid milk: 86.1, 29.3 and 2.4%; concentrated milk: 86.1, 26.5 and 5.7%, and reconstituted milk powder: 84.2, 31.8 and 10.9%). Surprisingly, this pattern was not observed in the SPAN value (which corresponds to the width or range of the size distribution based on the volume). Additionally, the increase in the homogenisation pressure did not affect the sorption isotherm pattern. These results demonstrate that increasing the homogenisation pressure decreases the particle size of the reconstituted powdered milk, indicating the potential for future studies on how this phenomenon affects its physicochemical and final product properties.

Advances in Low-Lactose/Lactose-Free Dairy Products and Their Production

With increasing health awareness worldwide, lactose intolerance has become a major concern of consumers, creating new market opportunities for low-lactose/lactose-free dairy foods. In recent years, through innovating processes and technologies, dairy manufacturers have significantly improved the variety, and functional and sensory qualities of low-lactose and lactose-free dairy products. Based on this, this paper first covers the pathology and epidemiology of lactose intolerance and market trends. Then, we focus on current advantages and disadvantages of different lactose hydrolysis technologies and improvements in these technologies to enhance nutritional value, and functional, sensory, and quality properties of lactose-free dairy products. We found that more and more cutting-edge technologies are being applied to the production of lactose-free dairy products, and that these technologies greatly improve the quality and production efficiency of lactose-free dairy products. Hopefully, our review can provide a theoretical basis for the marketing expansion and consumption guidance for low-lactose/lactose-free dairy products.

Freeze-dried human milk microcapsules using gum arabic and maltodextrin: An approach to improving solubility

Human milk (HM) is essential for newborns' food, but its low storage stability is a limiting factor so that microencapsulation may stabilize and protect compounds sensitive to degradation. This study investigated the action of maltodextrin and gum arabic on freeze-dried HM concerning its quality and solubility. Microencapsulation was evidenced by morphology, and all samples presented high encapsulation efficiency (>85 %), proving to be an efficient process. Furthermore, specific signals in the Fourier-Transform Infrared (FTIR) spectra indicate the interactions between the coating materials and the HM matrix. Gum arabic improved the reconstitution properties of freeze-dried HM (higher solubility, 3 % on average, and lower dissolution time, around 80 %), elucidating its high stabilization capacity, even at low concentrations (5 and 10 %). Despite the best results reached by gum arabic, the addition of maltodextrin proved effective; in other words, its low stabilization capacity enables combinations with gum arabic. A lower polidispersibility (difference of 20 % between samples: control and containing gum arabic) was also observed, which means that the encapsulated samples were more homogeneous. Therefore, through the analysis performed, we recommend using gum arabic alone or with maltodextrin to obtain HM microcapsules with a good quality of reconstitution.

Quality indicators in lactose hydrolyzed milks and soy beverages from Colombia

Worldwide there is great interest in producing low lactose milk and drinks, such as soy beverages, suitable for consumption by lactose-intolerant people. These products have different carbohydrate compositions, which affect quality indicators derived from Maillard reaction (furosine and 5-hydroxyl-methyl furfural, HMF). In this study, quality parameters have been determined in 11 commercial samples (8 lactose-hydrolyzed milks and 3 soy beverages). Presence of β-galactooligosaccharides in milks (22.2-458.1 mg/100 mL) correlating roughly with the remaining lactose content (1.9-357.7 mg/100 mL). Soy beverages contained α-galactosides in concentrations of 30-75 mg/100 mL. HMF and furosine were detected in all milk samples. In addition, powdered milks subjected to controlled storage (40 °C, a_w 0.44) showed a furosine increase up to 88%. In conclusion, a great composition diversity was observed in the different products, probably favored by the lack of regulation and underline the importance of controlling processing and storage conditions to preserve product quality.

Development of amperometric biosensor in modified carbon paste with enzymatic preparation based on lactase immobilized on carbon nanotubes

Abstract

The variety of products derived from milk, without or with lactose, encourages the development of more effective analytical techniques that can be applied to the quality control of both the production line and the final products. Thus, in this work an efficient and minimally invasive method for the detection of lactose was proposed, using a biosensor containing the enzyme lactase (LAC) immobilised on carbon nanotubes (CNTs) that, when reacting with lactose, emit an electrochemical signal. This biosensor was connected to a potentiostat, and its electrochemical cell was composed of the following three electrodes: reference electrode (Ag/AgCl), auxiliary electrode (platinum wire), and working electrode (biosensor) on which graphite (carbon) paste (CP), CNTs, and LAC were deposited. The transmission electron microscopy and scanning electron microscopy were used in the characterisation of the composite morphology, indicating excellent interactions between the CNTs and LAC. The sensitivity of the CP/LAC/CNT biosensor was determined as 5.67 μA cm^-2.mmol^-1 L and detection limits around 100 × 10^-6 mol L^-1 (electrode area = 0.12 cm²) and an increase in the stability of the system was observed with the introduction of CNTs because, with about 12 h of use, there was no variation in the signal (current). The results indicate that the association between the CNTs and LAC favoured the electrochemical system.

Graphic Abstract

How the heat treatment affects the constituents of infant formulas: a review

Abstract Breast milk as the children’s primary source of nutrition fulfills the babies’ needs and can also provide immune protection. In some cases, when mothers are not able to breastfeed, an equivalent substitute is required. Nowadays, the best substitutes of the human breast milk are infant formulas. Different technological routes may be designed to produce infant formulas according to the main challenges: the compromise between food safety and heat treatment damage. This article aimed to review the current scientific knowledge about how heat treatment affects the macro and micronutrients of milk, extrapolating the expected effects on infant formulas. The covered topics were: The definition and composition of infant formulas, industrial methods of infant formulas production, the effects of heat treatment on milk macro and micronutrients.

Lactose-Free Dairy Products: Market Developments, Production, Nutrition and Health Benefits

Lactose-free dairy is able to provide the essential nutrients present in regular dairy products, like calcium and vitamins, to those that are not able to digest lactose. This product category currently has a wide and growing health appeal to consumers. In recent years, the quality and product variety in the lactose-free dairy segment has been increasing significantly, giving consumers more tempting products to decide from. As a result, lactose-free dairy is now the fastest growing market in the dairy industry. This review discusses the market developments and production possibilities and issues related to the wide variation of lactose-free dairy products that are currently available. Additionally, the health benefits that lactose-free dairy may offer compared to dairy avoidance are illustrated.

Raman spectroscopy for the differentiation of Arabic coffee genotypes

The objective of this study was to evaluate the ability of Raman spectroscopy to identify the genotype of green coffee beans. Four genotypes of Arabic coffee: one Mundo Novo line (G1) and three Bourbon lines (G2, G3, and G4). The harvest was selected using a wet processing method. Raman spectra of the samples were obtained using a FT-Raman RFS/100 spectrometer in the spectral range of 3500-400 cm^-1. The data were treated using chemometric unsupervised classification tools and supervised analysis. Using the unsupervised analysis (PCA), the apparent tendency of agglomeration between samples G1 and G3 was verified. These differences were present in the spectral bands that are characteristic of fatty acids and kahweol. Based on this information, a classification model to discriminate (PLS-DA) the Mundo Novo and Bourbon samples was utilized. Raman spectroscopy allowed the building of an adequate model to differentiate between coffee genotypes.

Applications of Raman spectroscopic techniques for quality and safety evaluation of milk: A review of recent developments

Milk is a complete nutrient source for humans. The quality and safety of milk are critical for both producers and consumers, thereby the dairy industry requires rapid and nondestructive methods to ensure milk quality and safety. However, conventional methods are time-consuming and laborious, and require complicated preparation procedures. Therefore, the exploration of new milk analytical methods is essential. This current review introduces the principles of Raman spectroscopy and presents recent advances since 2012 of Raman spectroscopic techniques mainly involving surface-enhanced Raman spectroscopy (SERS), fourier-transform (FT) Raman spectroscopy, near-infrared (NIR) Raman spectroscopy, and micro-Raman spectroscopy for milk analysis including milk compositions, microorganisms and antibiotic residues in milk, as well as milk adulterants. Additionally, some challenges and future outlooks are proposed. The current review shows that Raman spectroscopic techniques have the promising potential for providing rapid and nondestructive detection of milk parameters. However, the application of Raman spectroscopy on milk analysis is not common yet since some limitations of Raman spectroscopy need to be overcome before making it a routine tool for the dairy industry.

Reduction of Phytic Acid in Soymilk by Immobilized Phytase System

In this study, three carriers (glass microsphere, cellulose beads and AlgNa/PVA beads) were evaluated as phytase solid carriers for reduction of phytic acid within soymilk. Phytase was covalently immobilized onto or entrapped within carriers for repeated use. Glass microsphere was chosen due to its high catalytic efficiency. Optimal operating condition (pH 6.0, 60 °C) was determined using 4-Nitrophenyl phosphate disodium salt hexahydrate as an indicator. Operational reusability was confirmed for more than seven batch reactions and the storage stability was capable of sustaining 70% of its catalytic activity for 40 days. The kinetic parameters including rate constant (K), time (τ₅₀ ) in which 50% of phytic acid hydrolysis was reached, and time (τ_complete ) required to achieve complete phytic acid hydrolysis, were 0.023 min^-1 , 35.7 min, 110 min. The current procedure provides a cheap as well as an easy way to carry out the reduction of phytic acid in soymilk, which has great potential in practical application.