**5. Possible approach for design of a dairy product with a satiety increasing effect**

An enrichment of peptides that can inhibit DPP-IV could result in increasing satiety after consumption of a dairy product. The most promising approach to steer the peptide profile of the

**Figure 3.** Targeting bioactive function in product development.

product is via fermentation with lactic acid bacteria. It would be promising to test different starter bacteria with different protease activities. Differences in their proteolytic action result in different peptide profiles. Then, an in vitro digestion model might be applied that is mimicking the digestion physiology of the target group. Next step would be peptide profiling and alignment of the results with already known sequences of DPP-IV inhibitory peptides. Furthermore, the inhibitory effect could be also tested using directly an enzyme assay. It is important to consider also all the other processing parameters that can affect protein digestion. Finally, the bioactive effect has to be confirmed in humans that represent the target group of the product (**Figure 3**).

**References**

copbio.2007.01.013

foods6050032

S0022-0302(98)75845-X

10.1111/j.1750-3841.2011.02455.x

[1] Haug A, Høstmark AT, Harstad OM. Bovine milk in human nutrition—A review. Lipids

Adjusting Bioactive Functions of Dairy Products via Processing

http://dx.doi.org/10.5772/intechopen.72927

121

[2] Kopf-Bolanz KA, Schwander F, Gijs M, Vergères G, Portmann R, Egger L. Validation of an in vitro digestive system for studying macronutrient decomposition in humans. The

[3] Korhonen H, Pihlanto A. Bioactive peptides: Production and functionality. International

[4] Hartmann RMH. Food-derived peptides with biological activity: From research to food applications. Current Opinion in Biotechnology. 2007;**18**:163-169. DOI: 10.1016/j.

[5] Kim S-K, Wijesekara I. Development and biological activities of marine-derived bioactive peptides: A review. Journal of Functional Foods. 2010;**2**:1-9. DOI: 10.1016/j.jff.2010.01.003 [6] Maestri E, Marmiroli M, Marmiroli N. Bioactive peptides in plant-derived foodstuffs.

[7] Choi J, Sabikhi L, Hassan A, Anand S. Bioactive peptides in dairy products. International Journal of Dairy Technology. 2012;**65**:1-12. DOI: 10.1111/j.1471-0307.2011.00725.x [8] Daliri EB-M, Oh DH, Lee BH. Bioactive peptides. Foods. 2017;**6**(5):32. DOI: 10.3390/

[9] Park O, Allen JC. Preparation of phosphopeptides derived from αs-casein and β-casein using immobilized glutamic acid-specific endopeptidase and characterization of their calcium binding. Journal of Dairy Science. 1998;**81**:2858-2865. DOI: 10.3168/jds.

[10] Ellegård KH, Gammelgård-Larsen C, Sørensen ES, Fedosov S. Process scale chromatographic isolation, characterization and identification of tryptic bioactive casein phosphopeptides. International Dairy Journal. 1999;**9**:639-652. DOI: 10.1016/S0958-6946(99)00135-1

[11] Pihlanto-Leppälä A, Paakkari I, Rinta-Koski M, Antila P. Bioactive peptide derived from in vitro proteolysis of bovine β-lactoglobulin and its effect on smooth muscle. The Journal

[12] Foltz M, Meynen EE, Bianco V, van Platerink C, Koning TM, Kloek J. Angiotensin converting enzyme inhibitory peptides from a lactotripeptide-enriched milk beverage are absorbed intact into the circulation. The Journal of Nutrition. April. 2007;**137**:953-958 [13] van Platerink CJ, Janssen H-GM, Horsten R, Haverkamp J. Quantification of ACE inhibiting peptides in human plasma using high performance liquid chromatography-mass spectrometry. Journal of Chromatography. B, Analytical Technologies in the Biomedical

[14] Udenigwe CC, Aluko RE. Food protein-derived bioactive peptides: Production, processing, and potential health benefits. Journal of Food Science. 2012;**77**:R11-R24. DOI:

of Dairy Research. 1997;**64**:149-155. DOI: 10.1017/S0022029996001926

and Life Sciences. 2006;**830**:151-157. DOI: 10.1016/j.jchromb.2005.10.036

Journal of Proteomics. 2016;**147**:140-155. DOI: 10.1016/j.jprot.2016.03.048

in Health and Disease. 2007;**6**:25. DOI: 10.1186/1476-511X-6-25

Journal of Nutrition. 2012;**142**:245-250. DOI: 10.3945/jn.111.148635

Dairy Journal. 2006;**16**:945-960. DOI: 10.1016/j.idairyj.2005.10.012

#### **6. Conclusion**

After ingestion of food containing protein, a peptide pattern is generated that probably contains bioactive sequences and is present in the jejunum before absorption takes place. Especially for dairy products, many different bioactive peptides could be identified that might be very interesting for the development of products with a specific functionality. The peptide patterns are strongly influenced by processing. Thermal treatments are used in general to ensure the microbial quality of dairy proteins. They exhibit a great influence on the protein structure for example by protein unfolding. Easier access is then given to the digestion enzymes and the resulting peptide profile is changed. Highly interesting is the fermentation of dairy products with different lactic acid bacteria strains. Certain strains have different protease activities and increase for example the number of antihypertensive peptides resulting after digestion. The angiotensinconverting enzyme inhibition is the most studied functionality and there are reports that could detect bioavailable peptides in the blood. The peptide concentrations reached for example in cheeses are promising to exhibit a bioactive function. Chemical and physical approaches can also influence the protein structure and therefore the protein digestion. The impact of new processing techniques on protein digestion should be always monitored. For the adjustment of a specific bioactive function in a product, an example approach is mentioned. However, it will always also depend on other factors whether the wished functionality is really reached or not. External factors like the meal composition and internal factors like age or genetic preconditions can also have an impact and have to be considered. Furthermore, for safety reasons, there is the small chance that generated de-novo peptides might act as epitopes for rare cases of cow milk allergy. However so far, fermentation with established lactic acid bacteria strains seems to reduce the allergenic potential of dairy products in general. In the future, it is necessary to perform well designed human studies that ensure a bioactive effect and allow the admission of health claims.

#### **Author details**

Katrin A. Kopf-Bolanz

Address all correspondence to: katrin.kopf@bfh.ch

Bern University of Applied Sciences, School of Agricultural, Forest and Food Sciences HAFL, Zollikofen, Switzerland
