Feeding concentrates with different protein sources to high-yielding, mid-lactation Norwegian Red cows: Effect on cheese ripening

Abstract

Soybean meal is one of the most important protein sources in concentrate feeds for dairy cows. The objective of the present study was to provide knowledge on the effects of using a novel yeast microbial protein source (Candida utilis) in concentrate feed for dairy cows on the production and quality of a Gouda-type cheese. Forty-eight Norwegian Red dairy cows in early to mid lactation were fed a basal diet of grass silage, which was supplemented with 3 different concentrate feeds. The protein source of the concentrates was based on conventional soybean meal (SBM), novel yeast (C. utilis; YEA), or barley (BAR; used as negative control because barley has a lower protein content). The experiment was carried out for a period of 10 wk, with the first 2 wk as an adaptation period where all dairy cows were fed grass silage and the SBM concentrate. The cows were then randomly allocated to 1 of the 3 different compound feeds: SBM, yeast, or barley. Cheeses were made during wk 8 and 9 of the experiment, with 4 batches of cheese made from milk from each of the 3 groups. The cheeses made from milk from cows fed SBM concentrate (SBM cheese) had a higher content of dl-pyroglutamic acid and free amino acids than the other cheeses, indicating a faster ripening in the SBM cheeses. Despite these differences, the sensory properties, the microbiota, and the Lactococcus population at 15 wk of ripening were not significantly different between the cheeses. This experiment showed that although the raw materials used in the concentrate feed clearly influenced the ripening of the cheeses, this did not affect cheese quality. Yeast (C. utilis) as a protein source in concentrate feed for dairy cows can be used as a replacement for soybean meal without compromising the quality of Norwegian Gouda-type cheeses.

A Snapshot, Using a Multi-Omic Approach, of the Metabolic Cross-Talk and the Dynamics of the Resident Microbiota in Ripening Cheese Inoculated with Listeria innocua

“…Similarly to our outcomes, Peng et al [ 83 ] claimed that Lactobacillus release antimicrobial molecules, like small organic acids, hydrogen peroxide, polypeptides, and lipid peroxides, to outcompete undesirable microorganisms in a time-dependent manner. The metabolite pyroglutamic acid has been previously quantified in many cheese varieties in ripened Italian cheeses produced with thermophilic lactic acid bacteria as starters and was proposed as a marker of the ripening process [ 84 ].…”

An integrated transcriptomic and metabolic phenotype analysis to uncover the metabolic characteristics of a genetically engineered Candida utilis strain expressing δ-zein gene

“…Yeast also contains various enzymes and hormones that promote animal metabolism and enhance animal digestion, leading to an overall improvement in the nutritional value of the feed. Additionally, this helps save protein resources and ultimately increases economic benefits ( Olsen et al, 2021 ). Among these options, food yeast stands out as an excellent feed ingredient, offering potential benefits in this context.…”

“…C. utilis , a type of single-cell protein (SCP), offers advantages such as a short production cycle, straightforward manufacturing process, high nutritional value, and low production cost ( Krahulec et al, 2020 ). Although C. utilis is rich in protein, B vitamins and various amino acids, its methionine content is relatively low ( Olsen et al, 2021 ). Maize endosperm contains a stable protein called δ-zein , which is abundant in sulfur amino acids, including methionine ( Kim et al, 2014 ).…”