Improving Dairy Supply Chain: From the Characterization and Authentication of Traditional Alpine Productions to Projecting New Dairy Functional Foods

The dairy industry is a global business, with millions of consumers worldwide and the industry has potential for development. In this thesis, we investigated ways of improving cheese and dairy production, focusing on improving the product quality, the safety for consumers and animals and investigating economic protection. Both traditional cheese production and novel production methods were investigated. By designing new products, the quality of dairy can be improved for the consumers. Functional Foods are regular food products with the addition of novel ingredients to improve its health benefits. Supplementing cheese with fruits or other plant parts can enrich the cheese with bioactive compounds or micronutrients. We tested the viability of this by supplementing models of Caciotta-like cheeses with blackcurrant (Ribes nigrum) or Cornelian cherry (Cornus mas), as they have a high content of polyphenols and dietary fiber. We tested fruits of different suppliers (organic or non-organic) and fruit preparation (freeze-dried or non-freeze-dried). The cheeses were evaluated for their health benefits by total polyphenol content and chemical composition. In addition, the microbial composition, organoleptic aspects and fermentation parameters were tested to ensure fermentation was not disrupted. The cheese supplemented with fruits had higher content of total polyphenol compared to control cheeses, particularly when non-organic fruits were used. The cheese supplemented with Blackcurrant stimulated the growth and activity of lactic acid bacteria, shown by higher counts, higher content of bacterial metabolites and lowered content of sugars. Supplement of the fruits did not affect the organoleptic properties of the cheese, excepts for the appearance. We showed that the cheeses enriched with Blackcurrant or Cornelian cherry increased the bioactive potential of the dairy product without serious adverse effect on the microbial community, physiochemical properties, or organoleptic properties. Certain niche productions produce unique dairy products, such as highland cow dairy farming. In the Italian Alps dairy farming is mostly performed in valley farms with indoor feeding. However, in the summer season most farmers move part of their herd to alpine farms that are located 1,400 to 2,000 m.a.s.l and allow cows to graze on the local pasture. The milk produced at these alpine farms is used to produce mountain cheese in local cheese factories. These mountain cheeses have high quality, unique taste, and have cultural, environmental and economic importance for the local populace. However, its production is costly due to lower yield and high transport costs. To protect this niche, we investigated the benefits and features of this production. The benefits from mountain dairy farming are thought to be mainly due to the pastural diet which includes alpine herbs. Cow diet supplementation can improve quantity and quality of dairy and reduce methane emissions, via modulating rumen microbiota. We investigated the effect alpine diet have on the rumen microbiota and environment by an in vitro trial, identifying beneficial and harmful parameters. We collected six herbs typical of Alpine pastures for fermentation and, as a control, we used typical cow feed used indoor (Graminaceae grass hay). Each herb was fermented in an in vitro system with rumen collected from experimental cows and the microbiota was examined by Illumina MiSeq Metagenomic analysis. The in vitro changes of rumen microbiota were related with the phytochemical composition of herbs, fermentation parameters and products. Rumen supplemented with herbs generally showed higher Firmicutes/Bacteroidetes ratio, higher relative abundance of Proteobacteria and Prevotella as well as a lowered abundance of Clostridia and Archaea, than control fermentation. When rumen was supplemented with Galium odoratum and Sanguisorba officinalis no archaeal methanogens were detected, and the lowest methane production was occurring. Supplement with Sisymbrium officinale, Cicerbita alpina, G. odoratum and Tanacetum vulgare showed higher abundance of bacteria taxa known to degrade plant fiber and polysaccharides. Rumen supplemented with S. officinalis had higher abundance of Streptococcus spp., and lowest microbial diversity, parameters that could be associated with rumen dysbiosis. Other than that, the herbs appeared as safe for cow feeding. Following this, we characterized the differences between commercial Nostrano cheeses made using cow milk either from highland mountain farming or indoor valley farming. The cheeses produced using mountain milk had improved content of saturated-, unsaturated fatty acids and conjugated linoleic acid, showing the higher nutritional quality of these cheeses. The microbial community and content of non-lipid compounds was primarily dependent on the cheese production parameters, and cheese with a longer ripening period had higher amounts of GABA and free amino acids. To protect the cheeses by authentication, we tested different methodologies for their ability to discriminate between the Nostrano cheeses made from either highland farmed milk or valley farmed milk. By stable isotope ratio analysis (SIRA) and Compound Specific SIRA (CSIA) we observed mountain and valley milk cheeses to differ by altitude dependent and diet dependent element ratios. By Nuclear Magnetic Resonance Spectrometry (NMR) and Fourier-Transform Infrared Spectrometry (FTIR) differences in the compound structure were detected. The different methods were evaluated for their ability to discriminate between cheeses using Linear Discriminant Analysis and Leave-One-Out Cross Validation. The methods with the highest classification accuracy between cheeses made from mountain or valley milk were NMR, SIRA and CSIA. These results show the viability for the development of an authentication system of mountain dairy. In this thesis a novel functional cheese with improved bioactive content was designed, the safe use of alpine herbs as supplement to cow feed was shown in vitro and the quality and viability of authentication of mountain milk cheese was shown.