Composition and Aroma Compounds of Ragusano Cheese: Native Pasture and Total Mixed Rations

Abstract

Raw milk from 13 cows fed TMR supplemented with native pasture and from 13 cows fed only TMR on one farm was collected separately 4 times with an interval of 15 d between collections. Two blocks (14 kg each) of cheese were made from each milk. The objective was to determine the influence of consumption of native plants in Sicilian pastures on the aroma compounds present in Ragusano cheese. Milk from cows that consumed native pasture plants produced cheeses with more odor-active compounds. In 4-mo-old cheese made from milk of pasture-fed cows, 27 odor-active compounds were identified, whereas only 13 were detected in cheese made from milk of total mixed ration-fed cows. The pasture cheeses were much more rich in odor-active aldehyde, ester, and terpenoid compounds than cheeses from cows fed only total mixed ration. A total of 8 unique aroma-active compounds (i.e., not reported in other cheeses evaluated by gas chromatography olfactory) were detected in Ragusano cheese made from milk from cows consuming native Sicilian pasture plants. These compounds were 2 aldehydes ([E,E]-2,4-octadienal and dodecanal), 2 esters (geranyl acetate and [E]-methyl jasmonate), 1 sulfur compound (methionol), and 3 terpenoid compounds (1-carvone, L(-) carvone, and citronellol). Geranyl acetate and (E)-methyl jasmonate were particularly interesting because these compounds are released from fresh plants as they are being damaged and are part of a possible plant defense mechanism against damage from insects. Most of the odor-active compounds that were unique in Ragusano cheese from pasture-fed cows appeared to be compounds created by oxidation processes in the plants that may have occurred during foraging and ingestion by the cow. Some odor-active compounds were consistently present in pasture cheeses that were not detected in the total mixed ration cheeses or in the 14 species of pasture plants analyzed. Either these compounds were present in other plants not analyzed, created in the rumen or in cheese after the pasture-plant material had been consumed, or the compounds were lost in the method of sample extraction used for the plant analysis (i.e., steam distillation) versus the solid-phase microextraction method used for the cheeses. This research has demonstrated clearly that some unique odor-active compounds found in pasture plants can be transferred to the cheese.

Use of Smart Nose and GC/MS/O analysis to define volatile fingerprint of a goatskin bag cheese “Bouhezza”

“…The same compounds were detected in Tulum cheese (Hayaloglu et al, 2007) and in Queso Ibores ripened cheese (Delgado et al, 2011). Previous studies on the aroma profile of cow's milk ripened Ragusano, sheep's milk ripened Piacentunu Ennese and goat's milk Spanish ripened cheeses described butanoic and hexanoic acids to have rancid/dirty sock and sweaty perception, in that order (Carpino et al, 2004;Horne et al, 2005;Poveda et al, 2008). Hexanoic and octanoic acids were found as common compounds.…”

“…In comparison with Turkish Tulum cheese, wich is also ripened in a goatskin bag, nine esters detected in farmhouse Bouhezza cheeses, were also found in Tulum (ethyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, n-propyl acetate, propyl hexanoate, 2-methyl-propyl acetate and 3-methyl-butyl butanoate) (Hayaloglu et al, 2007). Furthermore, ethyl ester of butanoic and hexanoic acids smelled like apple and orange notes, respectively, were also present in ripened cheeses made of both cow's and ewe's milks (Carpino et al, 2004;Horne et al, 2005). Ester chemical class that was responsible for fruity and floral notes in cheeses (Horne et al, 2005).…”

“…This technique has many advantages, as reported by Deibler et al (1999). Compounds from SPME are usually separated and identified by gas chromatography (GC) coupled to mass spectrometry (MS), to flame ionization detection (FID) and/or Olfactometry (Carpino et al, 2004;Mallia et al, 2008;Poveda et al, 2008;Serhan et al, 2010;Delgado et al, 2011).…”

The Microfloras and Sensory Profiles of Selected Protected Designation of Origin Italian Cheeses

“…This season is characterized by green forage consisting of diverse Mediterranean plants selected by cows, e.g., Calendula arvensis (Asteraceae), Geraniaceae (various species), Graminaceae (various species), unspecified short Asteraceae, and Fabaceae (various species), which contribute to the flavor profile of milk and cheese. These spontaneous pasture species comprised approximately 60% of the plant material selected by the grazing cows on a dry matter basis (8). Ragusano PDO cheese is produced traditionally by using wooden tools (tina, ruotula, mastredda, etc.).…”

World wide traditional cheeses: Banned for business?

“…The linkage with the territory has been demonstrated in a study concerning the influence of native plants in Sicilian pastures on the aroma compounds that are present in Ragusano cheese [8]. Cheeses that are obtained from milk produced by cows fed with native pasture plants presented more odor-active compounds.…”