Contents lists available at ScienceDirect International Journal of Food Microbiology journal homepage: www.elsevier.com/locate/ijfoodmicro Transformation of raw ewes' milk applying “Grana” type pressed cheese technology: Development of extra-hard “Gran Ovino” cheese Raimondo Gaglio a , Massimo Todaro a , Maria L. Scatassa b , Elena Franciosi c , Onofrio Corona a , Isabella Mancuso b , Rosalia Di Gerlando a , Cinzia Cardamone b , Luca Settanni a, ⁎ a Dipartimento Scienze Agrarie, Alimentari e Forestali, Università degli Studi di Palermo, Viale delle Scienze 4, 90128 Palermo, Italy b Istituto Zooprofilattico Sperimentale della Sicilia “Adelmo Mirri”, Via G. Marinuzzi 3, 90129 Palermo, Italy c Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, San Michele all'Adige, Italy ARTICLEINFO Keywords: Hard cheese Grana type cheese Illumina technology Lactic acid bacteria Raw ewes' milk Volatile organic compounds ABSTRACT Thisworkwascarriedouttopursueadoubleobjective:toimprovethehygienicsafetyofcheesesproducedfrom rawewes'milk;andtoproduceanewtypologyofrawewes'milkthroughtheapplicationof“Grana”technology for which the name “Gran Ovino” was chosen. With this in mind, raw milk from an individual farm was transformed under controlled conditions at a dairy pilot plant. The production technology included the partial skimming of the evening and morning milk mixture by cream surfacing and the addition of a natural whey starter cultures (NWSC) prepared with four selected Streptococcus thermophilus strains (PON6, PON244, PON261 e PON413). Ten microbial groups were investigated by plate counts from raw milk until ripened cheeses. Lactic acid bacteria (LAB) were in the range 10 4 –10 5 CFU/ml before NWSC addition. After curdling, this group in- creased by 3 log cycles and was counted at 10 6 CFU/g after curd cooking. A rapid pH drop (to 6.05) was registered after almost 3h from NWSC addition. The levels of members of the Enterobacteriaceae family were at about 10 3 CFU/mlinrawmilkanddecreasedaftercurdcookingto1logcycle.Asimilarbehaviorwasshownby the other undesired microbial groups and a complete disappearance of staphylococci was registered. The mi- crobiological counts of 9-month ripened cheeses showed the dominance of LAB and undetectable levels of the undesiredbacteria.MiSeqIlluminawasappliedtobetterinvestigatethebacterialcompositionofripenedcheeses and this technique evidenced that the majority of OTUs belonged to Lactobacillus and Streptococcus genera. The fnal cheeses were characterized by 67.65% dry matter of which 41.85% of fats and 47.02% of proteins. The main cheese fatty acids were palmitic, oleic and myristic acids and the saturated fatty acids/unsaturated fatty acidsratiowas2.17.Forty-onevolatilecompounds,includingacids,esters,ketones,alcohols,aldehydes,phenols and one terpene were emitted from the cheese. Sensory evaluation showed a general appreciation for the new cheese product by judges. 1. Introduction Olson (1990) afrmed that “there is a cheese for every taste and a taste preference for every cheese”. This statement evidences the high diversity of cheeses produced worldwide. In past, several technologies have been developed to transform a few raw materials, usually bovine, ovine, caprine or bufalo milks (McSweeney et al., 2004) and, nowa- days, a great diversity of dairy products, mainly cheeses, are available. Italy boasts a high range of traditional raw milk cheeses (Settanni and Moschetti, 2014) and, generally, each cheese possesses unique char- acteristics that depend on the transformation method applied. Milk, due to its richness in nutritional components, represents a growth medium for several microorganisms (Settanni and Moschetti, 2010). For this reason, raw milk may hosts human pathogens, dairy spoilers as well as useful fermentative agents, such as lactic acid bac- teria (LAB) (Franciosi et al., 2011). LAB found in raw milk are con- sidered “indigenous milk bacteria” but their presence derives from the contamination of the udder surface, of the milking procedures and milking equipment, stable environment, transport, vat surfaces, and dairy factory environment (Eneroth et al., 1998; Mc Phee and Grifths, 2002; Scatassa et al., 2015). These bacteria are fundamental to trans- form milk into cheese (Widyastuti and Febrisiantosa, 2014) because they are responsible for the acidifcation of the curd (starter LAB) and are implicated in the ripening process (non starter LAB) (Settanni and https://doi.org/10.1016/j.ijfoodmicro.2019.108277 Received 14 May 2019; Received in revised form 3 July 2019; Accepted 27 July 2019 ⁎ Corresponding author. E-mail address: luca.settanni@unipa.it (L. Settanni). International Journal of Food Microbiology 307 (2019) 108277 Available online 29 July 2019 0168-1605/ © 2019 Elsevier B.V. All rights reserved. T