Blog

The useful question here is whether native cultures can give a pasteurised goat’s milk cheese more character without losing control of acidification. Taboada and colleagues compared a native starter, the same starter organisms with native adjuncts, and a commercial Streptococcus thermophilus culture. The native combinations acidified effectively and produced cheeses rated more favourably by a trained panel after 30 days.

Cultures and the comparison

The native starter (S) contained Lactobacillus rhamnosus UNSE308 and L. delbrueckii subsp. bulgaricus UNSE309 at 30% each, with S. thermophilus UNSE314 and UNSE321 at 20% each. These are the names used in the paper.

The adjunct combination (A) retained the two lactobacilli at 30% each, reduced the two streptococci to 18% and 17%, and included four adjuncts at 1.25% each: L. plantarum UNSE316 and UNSE317, and Pediococcus pentosaceus UNSE22 and UNSE253. The comparison culture (C) was commercial S. thermophilus.

All cultures were activated and propagated before use. The native combinations were added to the cheese milk at 2% by volume; the commercial culture at 1%. These are active liquid culture additions, not equivalent doses of freeze-dried DVI powder.

Acidification curves

Figures 1A and 1B below compare 1%, 1.5% and 2% active inocula. The tests used pasteurised goat’s milk held at 38°C, with calcium chloride and chymosin, and pH readings every 30 minutes. Both native combinations reached pH 5.2 in four hours at 2%. The plotted 1.5% and 1% additions reached that point at five and six hours respectively. The authors report 4.5 hours for the commercial culture at 2%; that comparison was not plotted.

For cheesemakers: the inoculation rate changes the time available before the same pH is reached. The adjunct blend did not prevent rapid acidification at the higher addition. These are controlled milk acidification tests, not a measured pH curve through cutting, draining, pressing and brining. In particular, pH 5.2 is the test endpoint, not a reported cutting target for the make.

Make conditions

The cheeses were made in 35 L batches from milk pasteurised at 65°C for 30 minutes and cooled to 38°C. Coagulation lasted 40 minutes, followed by cutting to corn-sized curd, moulding and two hours of pressing. The cheeses were held at 5°C for 12 hours, brined in 16% w/v brine at 5°C for two hours, then ripened at 12°C and 85% relative humidity for 30 days. These conditions matter when comparing the results with a different make.

What happened during ripening

Cheese	pH, day 1	pH, day 30	Salt, day 30
Native starter (CS)	5.22	4.92	1.29%
Starter and adjuncts (CA)	5.20	4.88	1.27%
Commercial culture (CC)	5.24	5.05	1.25%

These are the reported mean pH measurements at two stages, not a continuous ripening curve. The native cheeses finished at a lower pH than the commercial comparison. Moisture was close to 49.7% in all three at day 30.

Proteolysis was slight. Non-protein nitrogen reached 4.54% and 4.49% of total nitrogen in CS and CA, compared with 4.18% in CC. That measure describes the soluble breakdown products of protein; it is not a direct percentage of free amino acids. Total free fatty acids were approximately 1.51, 1.53 and 1.47 g/kg respectively. The differences point to somewhat greater biochemical development with the native cultures, rather than a large change in overall cheese composition.

The trained panel rated the native cheeses “good” and the commercial comparison “regular”. The adjunct cheese had the highest creaminess and spiciness scores and the lowest bitterness. Its aroma also showed stronger fruity, propionic and goat’s cheese notes. For a cheesemaker, this is the more useful result: adjunct selection can change the character of the cheese even where the basic composition remains similar.

How far to take it

There were three independent makes per treatment and nine trained panellists. This supports a useful culture comparison under the stated conditions, not a general consumer preference claim or a transferable recipe for any commercial culture carrying the same species names. Strain identity, culture activity, milk and temperature still matter. I would use the curves to frame a trial and record pH through my own make, rather than lift the four-hour endpoint as a universal schedule.

Source and access

Taboada, N., Medina, R., Núñez, M. and López Alzogaray, S. (2017). Biochemical and microbiological changes throughout the ripening of Argentinean fresh goat’s milk cheeses made with native cultures. Journal of Microbiology, Biotechnology and Food Sciences, 6(5), 1174–1180. DOI and publisher record.

Open access: the article is licensed under CC BY 4.0. Open the full paper (PDF). Figures 1A and 1B are reproduced above from Taboada et al. (2017); the image is cropped from page 1177, with no changes to the plotted data.

A practical guide to applying food-grade PVA cheese coating, covering rind preparation, application, maintenance and removal. The aim is to limit moisture loss and protect the surface during maturation.

The method starts with a clean cheese that has dried thoroughly after brining. Apply a thin, even coat with a clean sponge, covering small holes and cracks, and allow it to dry fully. Follow with one or two further thin coats. The guide discusses coating consistency, occasional recoating, coloured finishes and sealing labels beneath a clear layer.

Troubleshooting centres on moisture and film thickness: peeling suggests an insufficiently dried surface, while uneven coverage and cracking call for thinner coats with adequate drying between applications. Natamycin-containing coatings are addressed separately, including rind removal. Hygiene points include using disposable sponges and keeping used coating out of the original container. This is a practical application guide rather than a controlled research study.

This is the latest one I was able to find on the web. Hopefully not too much has changed with DVI cultures since.

The book contains pretty rich information on the nature of the bacteria, flavour impact and typical styles of use. There is considerable overlap with the Culture Characteristics table which draws on this document as one of its key sources.