(1)BEER making 啤酒製程原理(英文)

簡單的說 (感恩連結wiki Brewing )

釀造啤酒，實際上是主要將麥芽中澱粉轉換成被稱為「麥汁」的含糖液體，再利用酵母將麥汁發酵成含有酒精的啤酒。

Typical Malt Yields in Points/Pound/Gallon

reference: http://howtobrew.com/book/section-2/what-is-malted-grain/table-of-typical-malt-yields

Malt Type	Max. Yield	Max. PPG	Typical PPG (85%)	PPG Steep
2 Row Lager Malt	80	37	31	--
6 Row Base Malt	76	35	30	--
2 Row Pale Ale Malt	81	38	32	--
Biscuit/Victory Malt	75	35	30	--
Vienna Malt	75	35	30	--
Munich Malt	75	35	30	--
Brown Malt	70	32	28	8*
Dextrin Malt	70	32	28	4*
Light Crystal (10 - 15L)	75	35	30	14*
Pale Crystal (25 - 40L)	74	34	29	22
Medium Crystal (60 - 75L)	74	34	29	18
Dark Crystal (120L)	72	33	28	16
Special B	68	31	27	16
Chocolate Malt	60	28	24	15
Roast Barley	55	25	22	21
Black Patent Malt	55	25	22	21
Wheat Malt	79	37	31	--
Rye Malt	63	29	25	--
Oatmeal (Flaked)	70	32	28	--
Corn (Flaked)	84	39	33	--
Barley (Flaked)	70	32	28	--
Wheat (Flaked)	77	36	30	--
Rice (Flaked)	82	38	32	--
Malto - Dextrin Powder	100	40	(40)	(40)
Sugar (Corn, Cane)	100	46	(46)	(46)

Malt % Yield data obtained and averaged from several sources.
Steeping data is experimental and was obtained by steeping 1 lb. in 1 gal at 160°F for 30 minutes. All malts were crushed in a 2 roller mill at the same setting.
* The low extraction from steeping is attributed to unconverted, insoluble starches as revealed by an iodine test.

釀造的第一個步驟稱為澱粉糖化，在這個階段，澱粉源（通常是大麥麥芽）與熱水混合形成麥汁（Wort）。熱水與碾碎的麥芽混合，混合液在「糖化鍋」內靜置1到2小時後，澱粉轉化成糖，甜麥汁從麥糟中被濾出。澱粉糖化之後，則開始進行「洗糟」。釀造者透過清洗麥糟來盡可能汲取可發酵的麥液。將麥粒從麥汁與洗糟水過濾出來的過程稱為「麥汁分離」（Wort separation）。

[In brewing and distilling, mashing is the process of combining a mix of grain (typically malted barley with supplementary grains such as corn, sorghum, rye, or wheat), and water, known as "liquor", and heating this mixture. Mashing involves pauses at certain temperatures (notably 45–62–73 °C or 113–144–163 °F), and takes place in a "mash tun". The end product of mashing is called a "mash". ]

傳統的麥汁分離方式（Lautering）是以麥芽的皮與殼作為自然的濾層，而許多現代化的啤酒廠則採用板框式壓濾機以提高生產效率。

經過洗糟的甜麥汁被打入稱為「銅鍋」的容器中煮沸（由於傳統的糖化鍋均為銅質)。麥汁中的水分在1小時左右的煮沸過程中逐漸蒸發，但糖分與其它成分則保留下來。煮沸使發酵糖（低分子澱粉）的作用更有效率。將麥汁煮沸的過程也同時破壞了液中酶的活性。啤酒花也在這個階段加入原液中，使啤酒帶有特有的苦味，風味與香味，啤酒花亦可分段加入。啤酒花煮沸時間越長，啤酒苦味也就越濃，但啤酒花香則越少。

煮沸的苦麥汁冷卻後即可添加酵母進行發酵。發酵的過程大約需時一周至一個月。發酵時間長短則視酵母種類與啤酒濃度而定。懸浮在麥汁中的懸浮粒子在發酵過程中沉澱，酵母在酵結束時亦會沉澱至溶液底部，得到清澈的啤酒（澄清）。發酵有時會分為前酵和後酵兩階段進行。啤酒即被移至另外的容器進行低溫發酵lagering（二次發酵）。二次發酵的目的，是為了延長啤酒的保存期限，或是提高啤酒的清澈度。