Peptide profile of Parmigiano Reggiano cheese after simulated gastrointestinal digestion: From quality drivers to functional compounds

Abstract

Time of ripening has a strong impact on shaping the valuable and recognizable characteristics of long-ripened types of cheese such as Parmigiano Reggiano (PR) due to the interrelationship between microbiota and proteolysis that occurs during ripening. The derived peptide profile is linked to cheese quality and represents the canvas for enzymes upon digestion, which could be responsible for the release of potentially bioactive peptides (BPs). In this study, we aimed at investigating the presence of BP in 72 PR cheese samples of different ripening times, from curd to 24 months of ripening, produced in six different dairies, and following their fate after simulated gastrointestinal digestion. A small number of peptide sequences sharing 100% similarity with known antimicrobial, antioxidant, and ACE-inhibitor sequences were found in PR cheeses, while a higher number of potential BPs were found after their simulated gastrointestinal digestion, in different amounts according to ripening time. Taking advantage of the complex organization of the sampling plan, we were able to follow the fate of peptides considered quality drivers during cheese ripening to their release as functional compounds upon digestion.

Effect of Ripening and In Vitro Digestion on Bioactive Peptides Profile in Ras Cheese and Their Biological Activities

“…Initially, caseins are hydrolysed by milk proteolytic enzymes and chymosin to large-and intermediatesize peptides. Next, the formed peptides are further hydrolysed into small peptides or free amino acids by proteinases and peptidases from starter and non-starter lactic acid bacteria as well as from adventitious microflora [5,7,8]. The first step of casein hydrolysis by lactic acid bacteria involves the proteolytic action of cell-envelope proteinases (CEPs) [9].…”

“…Previous studies highlighted that proteolysis during cheese manufacturing and ripening promoted the release of peptides with several biological activities [6][7][8]13]. Bioactive peptides are small peptides that exert proven beneficial effects on human health, which are normally encrypted in the parent proteins and released upon hydrolysis.…”

“…Therefore, the beneficial effects of bioactive peptides on human health depend on their stability during gastro-intestinal digestion. During digestion, in fact, bioactive peptides can be degraded or transformed into new bioactive sequences by the action of gastric and intestinal enzymes such as pepsin and pancreatic proteases [8]. Numerous studies have shown that in vitro digestion greatly affected the peptide profile of cheese with some peptides that were degraded during digestion, while others were released or increased in concentration [7,16,17].…”