β Cyclodextrin Nanocomplexes with Biologically Active Peptides from Hydrolysed Bovine Whey and Colostrum

β Cyclodextrin nanocomplexes with extensive whey and colostrum hydrolysates possessing acceptable flavor properties serve as potential sources of bioactive peptides. In this study, comparative characterization of dairy protein hydrolysates and their complexes with β cyclodextrin is presented. Antioxidant activity of studied samples was estimated by fluorometric method, the formation of clathrates with cyclic oligosaccharide was determined using thermogravimetric analysis. A significant decrease in bitterness of peptides included in cyclic oligosaccharides was established compared with samples of dairy hydrolysates. 2.1/1.3 fold increase in the antioxidant potential of β cyclodextrin clathrates with whey/colostrum hydrolysates was recorded versus unbound peptide fractions. According to toxicological tests on Tetrahymena pyriformis, the samples of whey hydrolysate and the resulting nanocomplex were referred to as non-toxic and slightly hazardous compounds, respectively. The dynamics of body weight gain and the relative weight coefficient of internal organs revealed no differences compared to the control group of Rattus norvegicus. The data on differentiation of blood cells, their death, and cytogenetic disorders demonstrated that a sample of cyclic oligosaccharides with whey peptides is non-toxic at the maximum dosages allowable for administration. β Cyclodextrin complexing with dairy peptides resulted in enhanced radical-reducing activity and improved flavor properties, making the clathrates promising and safe ingredients of special nutrition formulas.

Cold Microfiltration as an Enabler of Sustainable Dairy Protein Ingredient Innovation

Classically, microfiltration (0.1–0.5 µm) of bovine skim milk is performed at warm temperatures (45–55 °C), to produce micellar casein and milk-derived whey protein ingredients. Microfiltration at these temperatures is associated with high initial permeate flux and allows for the retention of the casein fraction, resulting in a whey protein fraction of high purity. Increasingly, however, the microfiltration of skim milk and other dairy streams at low temperatures (≤20 °C) is being used in the dairy industry. The trend towards cold filtration has arisen due to associated benefits of improved microbial quality and reduced fouling, allowing for extended processing times, improved product quality and opportunities for more sustainable processing. Performing microfiltration of skim milk at low temperatures also alters the protein profile and mineral composition of the resulting processing streams, allowing for the generation of new ingredients. However, the use of low processing temperatures is associated with high mechanical energy consumption to compensate for the increased viscosity, and thermal energy consumption for inline cooling, impacting the sustainability of the process. This review will examine the differences between warm and cold microfiltration in terms of membrane performance, partitioning of bovine milk constituents, microbial growth, ingredient innovation and process sustainability.

Whey Protein Powder Analysis by Mid-Infrared Spectroscopy

There is an ever-expanding number of high protein dietary supplements marketed as beneficial to athletes, body builders, infant formulas, elder care, and animal feed. Consumers will pay more for products with high protein per serving data on their nutritional labels, making the accurate reporting of protein content critical to customer confidence. The Kjeldahl method (KM) is the industry standard to quantitate dairy proteins, but the result is based on nitrogen content, which is an approximation of nitrogen attributable to protein in milk. Product tampering by third-party manufacturers is an issue, due to the lack of United States Food and Drug Administration regulation of nutraceutical products, permitting formulators to add low-cost nitrogen-containing components to artificially inflate the KM approximated protein content in products. Optical spectroscopy is commonly used for quality control measurements and has been identified as having the potential to complement the KM as a more nuanced testing measure of dairy protein. Mid-infrared (MIR) spectroscopy spectra of eight protein standards provided qualitative characterization of each protein by amide I and amide II peak absorbance wavenumber. Protein doping experiments revealed that as protein amounts were increased, the amide I/II peak shape changed from the broad protein powder peaks to the narrower peaks characteristic of the individual protein. Amino acid doping experiments with lysine, glutamic acid, and glycine, determined the limit of detection by MIR spectroscopy as 25%, suggesting that MIR spectroscopy can provide product quality assurance complementary to dairy protein measurement by the KM.

Whey Protein Powder Analysis by Kjeldahl and Mid-Infrared Spectroscopy

There is an ever-expanding number of high protein dietary supplements marketed as beneficial to athletes, body builders, infant formulas, elder care, and animal feed. Consumers will pay more for products with high protein per serving data on their nutritional labels, making the accurate reporting of protein content critical to customer confidence. The Kjeldahl Method (KM) is the industry standard to quantitate dairy proteins, but the result is based on nitrogen content, which is an approximation of nitrogen attributable to protein in milk. Optical spectroscopy is commonly used for quality control measurements and has been identified as having the potential to complement the KM as a more nuanced testing measure of dairy protein. Infrared (IR) spectroscopy offers advantages over the KM in that IR provides an accurate representation of protein content in dairy products, and the results can be achieved very quickly. Protein analysis by IR has been used to study protein degradation in aged cheeses, and milk whey powder adulteration in whey protein concentrate supplements. The hypothesis of this thesis is that if mid-infrared (MIR) spectroscopy can be used to characterize individual whey proteins, then MIR should be applicable to qualitative analysis of protein powders and quality control monitoring of protein powder products for adulteration by inexpensive protein or amino acids. Protein powder analysis by KM revealed that the calculated total percent protein of the five protein powders tested was lower than the value stated on the product label, the percent variation between label protein content and that of the KM ranged from 2.9% to 9.5%. MIR spectroscopy spectra of four whey protein standards and four other protein standards provided qualitative characterization of each protein by amide I and amide II peak absorbance wavenumber. Product tampering by third-party manufacturers is an issue, due to the lack of United States Food and Drug Administration regulation of nutraceutical products, permitting formulators to add low-cost nitrogen-containing components to artificially inflate the KM approximated protein content of the products. Protein powders have been found to be doped with the amino acids glycine, leucine, and glutamic acid and inexpensive proteins, like bovine serum albumin. Controlled doping experiments were conducted with each of the above listed adulterants to assess the effectiveness of MIR spectroscopy to rapidly detect product tampering. Protein doping experiments revealed that as BSA amounts were increased, the amide I/II peak shape changed from the broad protein powder peaks to the narrower BSA peaks. Amino acid doping experiments revealed that the limit of detection for MIR spectroscopy, for the three amino acids used in this study, is 25%. MIR spectroscopy results may offer product quality assurance that is complementary to dairy protein measurement by the KM.