Still more from Ishaq b. Sulaiman al-Israili, and this is an interesting section
Of the diversity of flours according to their milling
The diversity of flours according to their milling is fourfold: There is the soft kind that is perfectly ground and all equal. It provides ample nutrition and is quickly converted in the stomach. That which is not perfectly ground nor completely equal but in part coarse and in part small is hard to digest and slow to exit (the stomach) and because of its difference in grinding is digested remains long in the stomach. The diversity of flours according to the time of their milling is threefold: there is that which is freshly ground, that which is old, and that which is in the middle. Recently milled flour heats the body and constipates the belly, for its nature is shaped (adepta) by the turning (volutatione) of the mill. That is why it heats the stomach and dries up the moisture in exiting. That which is old heats the liver and is quickly ejected from the stomach. That which is middling old lies in the middle of these qualities and powers.
Of the diversity of breads
The diversity of bread is twofold: from their flour, and from their making (ex artificio). Their form is threefold, that is large, medium, and small. Large breads have more crumb (medulla, lit. marrow) and a harder and more subtle crust. The crust nourishes little because it is hard to digest, dries up the humidity on exiting (the stomach) and constipates the belly. The crumb is gross and viscous, humid, inflating, and generates viscous phlegm. (But) The fire penetrates the interior of small and subtle breads and dries the humidity of the crumb. Therefore they nourish little and are slow to exit (the stomach), and constipate the belly, especially if it be cold and one or two days after the baking.
Of the making of bread
The making of bread is divided into four ways: Some have as much salt and leavening (fermenti) as is needed and is well worked (subactus) and cooked as is proper. Others are little leavened and worked, and some are rested/risen less than necessary (a necessaria reperatia imminutus). Others have more salt and leavening than is sufficient, while others lack leavening and salt. That which is moderate in all the above things is perfectly digested in the stomach and generates purest blood in the body.
Bread that little fermented and little salted and no well cooked creates grossness and viscosity. It is thus harder and tougher to digest than the previously mentioned and more appropriate to the active and those with an abundance of heat due to the strength of their digestion.
Unleavened bread nourishes very little and is hardest to digest, and it has the property of generating constipation and wind. Therefore it is unsuited to people of any nature except those who exert themselves in greatest labours (…)
Of the diversity of breads according to the difference of fires
Fire is diverse in two ways: The first is by its nature, the second by its use (ex artificio). In its nature, it is diverse in three ways: Strong and large, or weak and gentle, or in the middle. Large and strong fires harden and dry the exterior of the bread and leaves the crumb (micam) not well cooked because the rapidly hardened crust does not allow the heat to penetrate to the interior. For there are two ways in which bread can be illaudible: If its crust is too hard and burned by the heat, and its interior does not nourish. Or is its crumb is gross and viscous and it therefore creates indigestion in all the humours.
Weak fire, by its nature, hardly penetrates to the interior (of the bread) and causes it to stay long until it completes its action. If the bread is taken off before it is fully cooked, it is viscous and thus it is needful to those of stronger digestion and the active. If it is taken away fully cooked, it is dry and hard to digest and causes constipation. The middling one is the temperate fire which equally reaches all parts of the bread, which is laudable, and each is cooked as is proper. This is good to the quiet and those who lack vigour such as the aged and convalescents.
Of the diversity of breads by their preparation
The diversity of bread according to its preparation is twofold: It is either cooked in an oven (in furno) or under a cloche (sub testis). That baked in an oven as is proper is easily digested and penetrates (the body) because the oven cooks the entire body of the bread, crust and crumb, fully. That which is baked under a cloche is worse because the fire only acts on a part of it and either leaves it gross and viscous or hard to digest so that if it is eaten often, it generates constipation and pain in the sides. Similarly if it is baked under the coals or ashes, it quickly dries on the outside and the inside remains gross and viscous and much ash and dirt is mixed in, so much so, that wood would be softer to eat, and it burns quickly. Hence it causes swelling of the members and heaviness and obscures the eyesight.
(…) p. 341 ff.
This is lengthy and not very helpful for reconstructing the bread that Constantinus Africanus was thinking of when he wrote his translation. It is a little more helpful for anyone who wants to try out reconstructing the cooking techniques, but even here the usefulness is limited. The text doesn’t even say what kind of leavening to use, presumably because surely nobody needed telling that.
A few considerations: We are not talking about flat breads. The author clearly prefers crumb over crust, but obviously not everybody concurred because small, crisp loaves seem to have been popular with some people. It is hard to say how large a loaf would qqualify as ‘large’, but the description of the crumb and crust suggests something bigger than a portion-sized bread and deeper than the typical flatbread.
While it is not clear what kind of oven a furnus is, it contrasts with a testudo and cooking in the ashes directly. That is interesting because it is not very much like the typical bread baking style of the Arab world, and very much like that of the Roman world. I would love to see this section compared with the Arabic original to see how far it was altered to fit the needs of its target audience.
Isaac Iudaeus de diaetis universalibus et particularibus, originally written in Arabic in the late ninth or early tenth century, was translated and adapted by Constantinus Africanus in the late 11th century and circulated widely in Italy and beyond soon afterwards. While the original applies to a different context, it is still reasonable to use it as a guide to the advice that Siculo-Normans would have found useful. It is an open question how much the original was altered in translation – I cannot say since I read no Arabic. However, the extensive reference to eating pork suggests that some alterations took place.