Nuts Roasting Machine

Nuts are cholesterol-free, but their fatty fraction contains sizeable amounts of chemically related

noncholesterol sterols belonging to a heterogeneous group of compounds known as plant sterols or

phytosterols (Table 1) [24]. They are non-nutritive components of all plants that play an important

structural role in membranes, where they serve to stabilize phospholipid bilayers just as cholesterol

does in animal cell membranes [37]. Phytosterols interfere with cholesterol absorption and thus help

lower blood cholesterol when present in sufficient amounts in the intestinal lumen. The mechanism of

action of phytosterols has been linked to their hydrophobicity, which is higher than cholesterol because

of a bulkier hydrocarbon molecule and entails a higher affinity for micelles than has cholesterol.

Consequently, cholesterol is displaced from micelles and the amount available for absorption is limited.

In all probability the phytosterol content of nuts contributes to their cholesterol-lowering effect (see

below).

Compared to other common foods, nuts have an optimal nutritional density with respect to healthy

minerals, such as calcium, magnesium, and potassium. Like that of most vegetables, the sodium

content of raw or roasted but otherwise unprocessed nuts is very low, ranging from undetectable in

hazelnuts to 18 mg/100 g in peanuts (Table 2) [24]. A high intake of calcium, magnesium and

potassium, together with a low sodium intake, is associated with protection against bone

demineralization, arterial hypertension, insulin resistance, and overall cardiovascular risk [39].

Obviously, the advantage of the low sodium content of nuts is lost if they are consumed as a

salted product.