SWISS CHEESE

Swiss cheese originated in the Emme Valley in Switzerland during the 15th century. The Swiss cheese is also called as Emmental cheese. This cheese is a hard variety known by its following characteristics:

Shining eyes with smooth waxy texture
Sweet nutty taste with a milk flavour
Swiss cheese should have a sliceable texture, regular, round holes, dull to brilliant appearance
45% minimum fat on dry weight basis
Mild nut like taste and a minimum of 60 days old before consumption.

Position in the world:

First - Cheddar cheese
Second - Mozzarella Cheese
Third - Swiss Cheese

How to make Swiss Cheese? - FLOW DIAGRAM

Milk
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Filtration/clarification
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Standardization(C/F=0.88)
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Heat treatment 63°C for 30 min.
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Cooling 32°C
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Starter addition

(Streptococcus thermophilus 1%, Lactobacillus delbrueckii subsp bulgaricus 0.045%;
Propionibacterium freudenreichii subsp shermanii 0.025%)
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Ripening 32°C for 55 min.
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Renneting 1.5g/100 liters
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Cutting
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Fore working 32°C for 40 min
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Pre-drawing 1/3rd whey
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Cooking 52° with in 30min
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Stirring at 52°C for 40min
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Pressing lightly for 1 ½ hours
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Pressing overnight
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Brining 23% brine for 48hrs
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Cold storage drying 7 days 8-10°C (85% R.H)
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Parafining
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Hot curing 22°C, 85% R.H. 6-8 weeks
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Cold curing (at 10°C)

Mechanism of eye formation in Swiss cheese

Propionic acid fermentation is the important type of fermentation taking place in Swiss types of cheese, which is brought about by propionic acid bacteria, chiefly Propionibacterium shermanii. These propionic acid bacteria grow under anaerobic conditions, utilizing calcium lactate as the substrate and produce propionate, acetate, water and carbon dioxide as end products.

In the presence of high salt concentration, part of carbon dioxide is produced by decarboxylation of amino acids (for example tyrosine and arginine) by enterococci. It has been reported that 50% of lactate is metabolized by propionibacteria and fermentation of lactate is happening at the center than in the periphery. The conducive atmosphere to initiate propionic acid fermentation are ripening temperature between 18-20°C, relative humidity around 85% and the duration between 6 and 8 weeks, leading to eye formation.

Different stages involved in carbon dioxide production and eye formation

CO2 Production & CO2 diffusion
(starts at beginning of lactic acid fermentation)
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Accumulation of CO2 in cheese body
(Propionic acid fermentation)
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Over saturation at the centers of the future eye formation
(Propionic acid fermentation)
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Onset of formation of eyes at these centers
(Approx 20-30days)
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Increase in the number of eyes.

Flavor

The flavor components of Swiss cheese are generally divided into two major groups. They are

1. Volatile: volatile fatty acids (VFA), primary and secondary alcohols, methyl ketones, aldehydes, esters, lactones, alkanes, aromatic and nitrogen containing compounds.

2. Non-volatile: peptides, peptones, fatty and amino acids, organic and inorganic acids and salts.

Volatile compounds	After hot curing (in 100 g of cheese)	After 140 days (in 100 g of cheese)
Propionic acid Acetic acid Butyric acid Higher fatty acids	344 mg 167 mg 18 mg 30 mg	630 mg 290 mg 38 mg 50 mg

Defects in Swiss cheese

S.No	Defect	Description	Probable-cause
1	Blind	No eyes	Over ripening (or) too acid milk
2	Small eyes	Less than 0.4”diameter	1. Excess gas generation 2. Disturbed curd
3	shell	Nut shell appearance on eye surface	1.Excess fat in milk and curd 2. Eyes that develop too slowly
4	Glass	Clear-cut parallel cracks if excess, cheese slice does not cut properly	1. Too acid and too fat rich milk 2. Poor whey drainage and curd becomes brittle
5	Frog mouth	Rind splits on surface to give appearance on open frog mouth	1. Poorly developed weak inelastic rind 2. Careless handling of cheese in press which becomes too cold
6	Blow hole	Very large eyes more than 5” in diameter	1. Poor sanitary conditions of milk production 2. Cows fed on grass and silage
7	Uneven/abnormal eye distribution	Cooled too quickly on one side
8	Whey spotted	1. Whey spotted 2. Poor whey drainage – becomes water logged on rind surface