English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Flavour is a sensory characteristic that may affect dairy products quality and acceptability. Several factors such as species, diet, management and environment strongly influence the aromatic profile of raw milk (Moio et al., 1993a; Bergamaschi et al., 2015) and related cheese (Povolo et al., 2007). In addition, cheese flavour depends on milk treatment (i.e., pasteurisation and homogenisation), starter bacteria, cheese manufacture and ripening length and conditions (Murtaza et al., 2014). Conversion of lactose and citrate, lipolysis and proteolysis are the main chemical and biochemical processes involved in the development of aroma in dairy products. Among these processes, proteolysis of caseins is an important biochemical pathway responsible for the formation of flavour and texture in hardand semi hard-type cheeses (van Kranenburg et al., 2002). During ripening, proteolysis is performed ABSTRACT. The aim of the study was to evaluate the effect of dietary inclusion of dried olive pomace (DOP) on proteolytic volatile compounds in raw milk and pasteurised milk cheese. Two groups of lactating cows (20 animals in each) were randomly assigned to isoenergetic and isoproteic treatments provided as control mixed ration (CON) and as CON with addition of 2 kg of DOP/day/animal (EXP). DOP partially replaced maize silage, alfalfa hay, sunflower and wheat. After 60 days of feeding, raw bulk milk was collected, sampled, pasteurised and used to produce cheese that was sampled at days 1, 7 and 30 of maturation. Samples were analysed by solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS) and data were expressed considering the relative peak area. In raw milk the phenyl-acetaldehyde and 2-phenylethyl alcohol, the only detected phenylalanine catabolites, were increased by dietary treatment by 61.9 and 235%, respectively (P < 0.01). In CON and EXP cheeses the compounds derived from phenylalanine, leucine and methionine catabolism were present being generally higher in EXP cheese during ripening time. In particular, among the volatile compounds, the contents of which were higher, were: the phenylacetaldehyde – 32.6% and 34% higher at days 7 and 30 (P < 0.01 and P < 0.05, respectively); the 2-phenylethyl alcohol – 229% higher at day 7 (P < 0.001), the 3-methyl-1-butanol – 299% and 59.1% higher at days 7 and 30 (P < 0.001 and P < 0.05, respectively), the isoamyl butyrate – 58.2% higher at day 30 (P < 0.05) and the isoamyl isopentanoate – 290% and 60.1% higher at days 7 and 30 (P < 0.01 and P < 0.05, respectively). Dietary DOP addition may affect aroma of dairy products, however the sensory evaluation panel test is needed to complete the feedback supporting industry choices. Received: 25 October 2017 Revised: 7 September 2018 Accepted: 19 November 2018

Proteolytic volatile compounds in milk and cheese of cows fed dried olive pomace supplementation