Effect on the Antioxidant, Lipoperoxyl Radical Scavenger Capacity, Nutritional, Sensory and Microbiological Traits of an Ovine Stretched Cheese Produced with Grape Pomace Powder Addition

Abstract

An innovative ovine cheese enriched with red grape pomace powder (GPP) was produced to improve the functional properties of Vastedda cheese typology. Vastedda cheese making was performed adding GPP and four selected Lactococcus lactis strains (Mise36, Mise94, Mise169 and Mise190). For each strain, 40 L of pasteurized ewe’s milk was divided into two aliquots representing control and experimental trials. Control cheese (CC) production did not contain GPP, while the experimental cheese (EC) production was enriched with 1% (w/w) GPP. GPP did not slow down starter development and acid generation. Plate counts and randomly amplified polymorphic DNA (RAPD)-PCR analysis confirmed the dominance of the starters in all trials. The evolution of the physicochemical parameters showed that EC productions were characterized by lower fat content, higher protein content, and higher values of secondary lipid oxidation. Sensory evaluation indicated that the cheeses produced with the strain Mise94 were those more appreciated by the judges. Thus, the last cheeses were investigated for some functional aspects: GPP enrichment significantly increased antioxidant activity and lipoperoxyl radical scavenger capacity, confirming that grape polyphenol inclusion in cheese represents an optimal strategy for the valorization of ovine cheeses as well as winemaking industry by-products.

Development of “Quadrello di Ovino”, a Novel Fresh Ewe’s Cheese

“…These results were quite expected, due to the high content of dry matter, proteins and fats of ewe's milk [54]. Furthermore, the compositional analysis of ovine QdO cheeses showed data comparable to those measured for other ovine fresh cheeses such as pressed Primosale cheese and stretched Vastedda-like cheese [8,16]. QdO-P1 cheese showed a higher antioxidant activity, in terms of TBAR S , than QdO-P2 cheese.…”

“…These results might be ascribable to the ability of the indigenous milk bacteria to survive during the pasteurization process [ 41 , 42 ], but also to a post-pasteurization contamination [ 43 , 44 ]. Furthermore, this phenomenon seems to be common in pasteurized ewe’s milk [ 8 , 16 , 45 ]. All undesired bacteria ( Pseudomonas , members of Enterobacteriaceae family, L. monocytogenes , Salmonella spp., E. coli and CPS) were undetectable.…”

“…The two main Italian islands, Sicily and Sardinia, represent the regions where sheep milk is produced at consistent levels [ 15 ]. In order to contribute to the rural development and to impact positively on the local regional economy, Sicilian research institutes and cheese producers are collaborating to offer new dairy products with the aim of limiting the land abandonment phenomenon, particularly common in the internal hilly areas [ 16 ]. Generally, Italian hard cheeses processed from ewe’s milk are referred to as “Pecorino” cheeses [ 17 ].…”

Effect of grape pomace from red cultivar 'Nero d’Avola' on the microbiological, physicochemical, phenolic profile and sensory aspects of ovine Vastedda-like stretched cheese

“…Fifteen grams of GPP were transferred into a sterile stomacher bag, added with 135 ml of Ringer's solution (Sigma Aldrich) and homogenized in the Bag-Mixer 400 stomacher (Interscience) for 2 min at the maximum speed. Homogenized GPP was then subjected to the decimal serial dilution in Ringer's solution (1:10) and the cell suspensions were used for the plate count of the main microbial groups belonging to the pro-technological, spoilage and pathogenic populations following the approach of Gaglio, Restivo, et al (2021). Briefly, total mesophilic microorganisms (TMM) on Plate Count Agar (PCA); mesophilic and thermophilic LAB cocci on Medium 17 (M17) agar; mesophilic and thermophilic LAB rods on de Man-Rogosa-Sharpe (MRS) agar; enterococci on Kanamycin Esculin Azide (KEA) agar; members of Enterobacteriaceae on violet red bile glucose agar (VRBGA); coagulase-positive staphylococci (CPS) on Baird Parker (BP) supplemented with rabbit plasma fibrinogen (RPF); Listeria monocytogenes on Listeria selective agar base with SR0140E supplement; Salmonella spp.…”

Monitoring Commercial Starter Culture Development in Presence of Red Grape Pomace Powder to Produce Polyphenol-Enriched Fresh Ovine Cheeses at Industrial Scale Level

“…The addition of GPP in bovine dairy products such as yogurt [21,22] and semihard and hard cheeses [23] has been investigated and their effect on the nutritional quality of the processed foods evaluated. Very recently, the addition of GPP to fresh ewe's milk cheese has been investigated using single Lactococcus lactis strains at the pilot plant scale level [24], but no industrial production has been carried out. In order to perform high volume cheese production, commercial starter cultures are of paramount importance because they include several mixed-strain starters to overcome phage related issues [25].…”