Chapter 14: Milk into Cheese

Milk for the vulnerable: 63 °C held 30 min with stirring; the finger cue for 63 °C; raw-milk hazards (Coxiella, Listeria, Brucella, E. coli O157)

To check against

doc 80, 137; BfR raw-milk guidance; Tier-LMHV § 17; replace the finger cue with a safer visual or a made thermometer

The verdict

AMENDED

Found

law.cornell.edu/cfr/text/21/133.3 (21 CFR 133.3(d): "every particle" held at 145 °F, 62.8 °C, for 30 min; add 5 °F if fat is 10 % or more); pubs.nmsu.edu/_e/E216/ (NMSU extension: 60 to 62.8 °C, stirred, 30 min; "Use a cooking thermometer"); bfr.bund.de/presseinformation/rohmilch-abkochen-schuetzt-… (BfR 11/2014: raw milk from the farm should always be boiled; children, pregnant, old and sick people should avoid raw milk and raw-milk products; pathogens named: Campylobacter, EHEC, Salmonella, Listeria, Q fever); gesetze-im-internet.de/tier-lmhv/__17.html (§ 17(4) Nr. 4: sign "Rohmilch, vor dem Verzehr abkochen"); bfr.bund.de/cm/350/verbrauchertipps-schutz-vor-lebensmitt… (BfR leaflet p. 4: risk groups avoid raw-milk butter and raw-milk cheese except long-ripened hard cheese); Wikipedia "Scalding" (route; American Burn Association: scald at 60 °C within 5 s)

Note

63 °C for 30 min, stirred, is confirmed (62.8 °C in 21 CFR; for cream add 3 °C). The finger cue is unsafe and unreliable: water at 60 °C scalds in about 5 s, and 50 °C and 70 °C both feel "too hot to keep a finger in". Without a thermometer, the official German advice is to bring it to the boil. The hazard list should put Campylobacter first (BfR: the most common raw-milk infection) and keep EHEC, Listeria and Q fever; Brucella is not named by BfR. The Bench line "Cheese and butter are made from raw milk and made safe by salt, sourness and time" contradicts BfR for the vulnerable: they should not eat raw-milk butter or raw-milk cheese other than long-ripened hard cheese. Proposed: "For a child, a pregnant woman, an old person or anyone ill, heat the milk to 63 degrees on a thermometer and hold it there for 30 minutes, stirring; without a thermometer, bring it to the boil. They should not eat raw-milk butter or fresh raw-milk cheese at all, only the long-ripened hard wheel."

Strip cup test; milk from a flaky, clotted or bloody quarter is never used for cheese

To check against

doc 80, 137; FAO T0218E, Milking, milk production hygiene and udder health

The verdict

AMENDED

Found

fao.org/4/t0218e/T0218E03.htm and T0218E04.htm (FAO Animal Production and Health Paper 78: foremilking "is an effective way of detecting clinical symptoms of mastitis"; clots in the milk are the clinical sign; foremilk cups must be cleaned and disinfected after each milking); fao.org/4/ba0027e/ba0027e00.pdf (FAO/IDF Guide to good dairy farming practice, 2011, pp. 25 and 28: milk from sick animals "is not suitable for human consumption"; milk such animals last or with a separate bucket; discard abnormal milk in a manner appropriate to the risk to people, animals and the environment); doc 80 p. 5 and doc 137 p. 20 (dark strip cup, flakes, clots, blood, watery milk)

Note

The strip cup and the signs are confirmed. Two parts go beyond the guidance: stripping the bad quarter "onto the ground" spreads contagious mastitis to the next animal that lies there (FAO/IDF: dispose with regard to risk to animals); and "keep the rest" of that animal's milk is not supported, since FAO/IDF treats milk from a sick animal as unfit for food. Proposed: "Flakes, clots, blood or watery milk mean that quarter is ill: milk that animal last, into a separate pail, pour it away where no animal lies, and keep none of her milk for the house or the cheese until the cup runs clean again."

Milk at body heat doubles its bacteria every 20 min; keeps 2 days at 10 °C, most of a week at 4 °C

To check against

doc 137 (under 20 min warm); Walstra, Dairy Science and Technology; amend the 10 °C and 4 °C figures

The verdict

AMENDED

Found

doc 137 p. 22 (doubling time at body heat under 20 min; chill within two hours; research PDF only); fao.org/4/t0218e/T0218E05.htm (FAO: if cold water below 15 °C is not available, milk should go to a cooling depot within 3 h); gesetze-im-internet.de/tier-lmhv/__17.html (§ 17(2): raw milk sold as Vorzugsmilch must stay at or below 8 °C and its use-by date may not exceed 96 h after milking; farm-gate raw milk only from that day or the day before); BfR Listeria leaflet p. 3 (fridge at most 7 °C, better below 5 °C)

Note

The 20-minute doubling is from doc 137 only; Walstra not reachable, so treat as the book's own. The keeping times are too long against the only legal benchmark: raw milk from specially licensed, inspected farms, kept at or below 8 °C, may be sold for at most 96 hours (4 days) after milking; farm-gate raw milk no more than a day old. Nothing supports two days at 10 °C. Proposed: "Milk at body heat multiplies its bacteria fast, so get it cold within two hours. In a cellar or trough at ten degrees, use it the same day or the next; at four degrees, within three or four days."

Mozzarella kept at most 3 days in light soured brine (15 to 20 g/l); Listeria grows in the cold and endangers the pregnant and the old

To check against

doc 87 (1 to 2 % brine, pH 5.2); EFSA/BfR on Listeria in soft cheese; the 3-day limit is the book's own

The verdict

AMENDED

Found

bfr.bund.de/presseinformation/listeriose-selten-aber-gefa… (BfR 30/2018: Listeria multiplies at fridge temperatures; old people, pregnant women, the immunocompromised and newborns at risk; 7 % of 2016 German cases fatal; perishable foods used within two to three days); bfr.bund.de/cm/350/verbrauchertipps-schutz-vor-lebensmitt… (BfR leaflet p. 4: risk groups should avoid "eingelegter Käse oder Frischkäse aus offenen Gefäßen wie Feta ... oder Mozzarella" unless heated to 70 °C core; fridge at most 7 °C, better below 5 °C); doc 87 p. 10 (storage liquid 1 to 2 % salt, pH about 5.2, calcium)

Note

The Listeria statement is confirmed. The brine (15 to 20 g/l, soured) matches doc 87. The 3-day limit is the book's own; it matches BfR's two to three days only in a fridge at 7 °C or below, and a 10 to 13 °C cellar is warmer. BfR advises risk groups against mozzarella in brine entirely unless heated. Proposed: "Keep it in a light brine, 15 to 20 grams of salt per litre, soured with whey, in the coldest place you have, and eat it within two days; a pregnant woman, an old person or anyone ill eats it only cooked, melted hot on bread or in a dish."

Cheese brine: saturated, soured with whey, calcium added, skimmed, never discarded; wheel 12 h per kg

To check against

doc 125, 94; Caldwell, Mastering Artisan Cheesemaking (2012); Kindstedt; overlaps S6

The verdict

AMENDED

Found

cheesemaking.com/blogs/learn/how-to-make-and-use-salt-bri… (New England Cheesemaking Supply: salt "until it no longer dissolves"; brine pH "similar to the cheese being salted ... around 5.4-4.9", target 5.2; calcium chloride or whey so the brine does not pull calcium from the cheese; "One hour per pound, per one inch thickness"; "We generally keep same brine for 1-2 years"; if mould or cloudiness appears, "simply boil and filter it"); solubility of NaCl about 360 g per litre of water at 20 °C (standard chemistry, gives 26.4 % w/w; no handbook page opened); doc 125, 94

Note

Saturated, soured, calcium added and skimmed are confirmed; 360 g per litre of water is the saturation point. Two parts go beyond the source: "never discarded" and "used for a decade" (NECS keeps a brine 1 to 2 years and boils and filters it when mould or cloudiness appears); and "12 h per kg" is the book's own rule, which is longer than the NECS rule for a small, thin wheel. It also differs from S6's "6 to 12 h per kg": the two chapters should give one figure. Caldwell and Kindstedt not opened. Proposed: "Leave it about 12 hours per kilogram for a thick wheel, less for a thin one, turning halfway. Keep the brine covered and cold, skim it, top it up with salt, and when it turns cloudy or grows a skin, boil it, strain it through cloth and cool it before the next wheel goes in."

Mould rules: brush blue and green off dry; cut away black and pink; discard a slipped bloomy rind; mites mean brushing outdoors and lye on the boards

To check against

doc 94 (no cut-away rule given); Caldwell; BfR on mould on cheese; a cheesemaking text on mites

The verdict

AMENDED

Found

bfr.bund.de/fragen-und-antworten/thema/schimmelpilze-in-l… (BfR FAQ: milk and dairy products among the foods most prone to mould; mouldy foods should not be eaten; only exceptions are air-dried salami and whole ham, cut away generously; Edelschimmel on Brie and Camembert safe); web.archive.org/web/2025/https://www.fsis.usda.gov/food-s… (USDA FSIS, archived because the live page returns 403: hard cheese, "Cut off at least 1 inch around and below the mold spot", keep the knife out of the mould; soft cheese and Brie or Camembert with foreign moulds, discard); doc 94 pp. 6 to 8 (unwanted blue-green Penicillium on hard and bloomy cheeses; brushing destroys Mucor hyphae; slip skin on bloomy cheese)

Note

Brushing ordinary moulds off a ripening hard rind is traditional affinage (doc 94) and not contradicted by any agency, since neither BfR nor FSIS addresses a rind still in the cave. "Black and pink cut away to clean cheese" is too loose: FSIS requires at least 2.5 cm around and below the spot on a hard cheese, and BfR allows no cut-away on dairy at all. Discarding a slipped bloomy coat with ammonia matches FSIS for soft cheese. The mite advice (brush outdoors, lye on the boards) has no source opened; no lye strength is given and lye on wood needs gloves, eye protection and a thorough rinse. Proposed: "Black, pink or any mould that is not the cellar's usual blue-grey on a hard wheel: cut it out with a clean knife to a thumb's width, 2.5 centimetres, around and below, and eat that piece soon. On a soft or fresh cheese any foreign mould means the whole cheese goes."

Ghee at 110 to 120 °C, never past 150 °C; keeps a year dark and cool; about 30 min per kg

To check against

doc 83 (no keeping time given); a ghee standard (FSSAI) or dairy text

The verdict

AMENDED

Found

fao.org/4/t0251e/T0251E04.htm (FAO Animal Production and Health Paper 85, The technology of traditional milk products in developing countries: makkhan "heated to about 110 to 120°C with constant stirring over a low fire"; end point "a second effervescence, which is much finer than the first, together with the browning of the curd particles"; higher heating gives "a burnt or overcooked flavour"; Indian legal moisture maximum 0.5 %; ghee "keeps for more than 6 months at normal room temperature"); doc 83 pp. 9 and 11 (110 to 120 °C; above 150 °C, AGE build-up and cholesterol oxidation)

Note

110 to 120 °C and the double-foam, hazelnut-brown cue are confirmed by FAO. "Never past 150" is a quality ceiling supported by doc 83 only, and is conservative, not a hazard line. "Keeps a year" goes beyond the source, which gives more than six months at room temperature; cool and dark storage plausibly extends it, but no figure was found. The half hour per kilogram is the book's own. FSSAI standard not reached. Missing safety point: the ghee keeps only if every drop of water is gone (FAO: at most 0.5 % moisture), and hot fat must never meet water. Proposed: "Stop there, at about 110 to 120 degrees; much hotter and it tastes burnt. Pour through cloth into a hot, dry jar, and keep water away from the hot pan. Kept dark and cool it lasts at least six months, and usually far longer; if it smells sharp or like old paint, it has gone rancid."

Only tinned copper, glazed earthenware, steel or scalded wood; bare copper spoils milk within the hour

To check against

doc 80 (copper limit 4 mg/kg, hexanal); Council of Europe CM/Res(2013)9; the "within the hour" is rhetorical

The verdict

AMENDED

Found

doc 80 (copper limit 4 mg/kg; copper catalyses hexanal, the oxidised "cardboard" flavour; research PDF only); bfr.bund.de/cm/343/geschirr-aus-keramik-bfr-empfiehlt-nie… (BfR opinion 043/2020, p. 1: glazes can contain lead, cadmium and cobalt; release depends on glaze quality, firing temperature and the food, "z. B. saure Lebensmittel", and contact time; limits in Directive 84/500/EEC); tried: EDQM page for Council of Europe CM/Res(2013)9 and the metals technical guide (403), rm.coe.int (403), BfR copper FAQ (intake figures only, nothing on cookware)

Note

The list of safe materials is sound, but "glazed earthenware" needs a caveat: old, home-made or foreign glazes can release lead into sour milk, whey and brine (BfR 043/2020). The copper claims (the release limit, the oxidised flavour) rest on doc 80 alone; CM/Res(2013)9 could not be opened. "Within the hour" is rhetorical; say "quickly". Proposed: "Only ever use tinned copper with the tinning whole, steel, well-scalded wood, or earthenware with a glaze you know to be lead-free; old and home-made glazes can give up lead to anything sour. Bare copper quickly gives milk a taste of wet cardboard."

Calf vell: salt at 15 % of its weight plus half its weight in water, 18 to 21 °C, 3 to 7 days; dry below 21 °C; grind 1:8 in sour whey with 4 to 5 % salt; keeps 6 months cold; hygiene of raw gastric tissue

To check against

doc 84; Caldwell, DIY Traditional Rennet (2016); food-safety view of brining raw offal

The verdict

AMENDED

Found

doc 84 pp. 7 to 8 (15 % of stomach weight in salt, 50 % in water, 18 to 21 °C, 3 to 7 days; worked example 174 g, 26.1 g, 87 g; research PDF only, citing Caldwell); fda.gov/media/80637/download (FDA Fish and Fishery Products Hazards and Controls Guidance, June 2022, PDF p. 306: water-phase salt "of at least 20%" is "based on the maximum salt level for growth of S. aureus"; p. 299: water activity below 0.85 is the minimum for S. aureus toxin; p. 297: C. botulinum type A minimum growth 10 °C); tried for the figures: Caldwell, DIY Traditional Rennet (not reachable), FAO T0251E (mentions pieces of calf stomach in whey as coagulant, no figures)

Note

The 15 % and 50 % figures match doc 84, but no primary source was opened for them, and the food-safety claim does not hold: 26 g salt in 85 g water plus the water in a 170 g stomach (roughly 130 g at 75 to 80 % water) gives a water-phase salt of only about 10 to 11 % at equilibrium (arithmetic from the book's figures), well below the 20 % FDA gives as the ceiling for S. aureus growth. At 18 to 21 °C for up to a week, raw gastric tissue can grow S. aureus. The later drying to "parchment" is the real safety step and matches the FDA water-activity barrier. The 1:8 paste, 4 to 5 % salt and six months cold are the book's own and unverified. Proposed: "Salt it with coarse salt at 15 parts in 100 of its weight and half its weight of water, and keep the crock in the cellar, not the kitchen, for 3 to 7 days; then dry it until it snaps. Handle it like raw meat: clean hands, clean knife, scalded crock."

Mascarpone: cream about 25 % fat to 85 to 90 °C; vinegar 20 to 30 ml/l; drain 20 to 24 h; eat within 3 days; about 700 g per litre

To check against

doc 88 (drain at 4 to 10 °C, no acid dose), 128 (mass balance); a mascarpone reference; the vinegar dose, the cellar drain and the yield are the book's own

The verdict

AMENDED

Found

doc 88 pp. 1 and 14 (cream 20 to 26 % fat, 85 to 95 °C, citric or tartaric acid; traditional draining 20 to 24 h "in a cold environment (4°C to 10°C)"); doc 128 pp. 6 to 7 (fat recovery about 80 %, finished mascarpone about 50 % fat); europepmc.org/article/PMC/PMC8972315 (Biomed Rep 2022, review of cheese botulism: 1996 outbreak in Campania and Calabria, 8 cases of type A botulism from mascarpone and unheated tiramisu; toxin production favoured by storage above the prescribed temperature; cites Aureli et al., Lancet 1996, doi 10.1016/S0140-6736(05)66220-4, and Franciosa et al., J Food Prot 1999, doi 10.4315/0362-028x-62.8.867); FDA Hazards Guide June 2022 p. 297 (type A C. botulinum grows from 10 °C)

Note

25 % cream, 85 to 90 °C and 20 to 24 h draining are confirmed by doc 88 only; the vinegar dose is the book's own. Two corrections. Yield: the mass balance in doc 128 gives 1 litre of 25 % cream × 0.8 fat recovery ÷ 0.5 fat in the product, about 400 g, not 700 g. Safety: heating to 85 to 90 °C does not kill botulinum spores, and mascarpone is low in acid and salt; the 1996 Italian outbreak came from mascarpone kept too warm. Draining "in the cellar" at 10 to 13 °C sits at or above the 10 °C growth threshold for type A. Proposed: "Drain it in a double cloth in the coldest place you have, under 10 degrees, for 20 to 24 hours, no longer. A litre of cream gives about 400 grams. Keep it cold and eat it within three days; never leave mascarpone or a tiramisu standing in a warm room."