Control calórico y contenido de colesterol de la carne normal y baja en grasas y productos carnicos

Trends in Food Science & Technology 10 (1999) 119±128

Review

Calori®c value and cholesterol content of normal and low-fat meat and meat products
R. Chizzolini,* E. Zanardi, V. Dorigoni and S. Ghidini
Istituto di Scienza e Tecnologia degli Alimenti, Á Universita di Parma, 43100 Parma, Italy (fax: +39-0521-902752)
This review deals with the topic of fat and cholesterol intakes derived fromthe consumption of meat and meat products and the impact that the development of low-fat products might have. The relationships between fat and cholesterol intake and blood cholesterol levels are discussed in the light of the most recent ®ndings. The calori®c value and the cholesterol content and, therefore, the relative dietary contribution of meats are discussed in relation to animal species,type of muscle and main representative products. The relationship between fat and cholesterol content in meat is thoroughly examined. The lowering of fat content in fresh meat and in meat products is analysed in relation to the proposed aim of reducing calori®c value and, possibly, the amount of cholesterol. The e€ect of cooking is also reviewed. Some ®nal comments are devoted to the oxidativehypothesis of chronic cardiovascular diseases. # 1999 Elsevier Science Ltd. All rights reserved. International medical institutions have been recommending for the past 40 years that dietary fat intake should be controlled as quantity of calories and type of
* Corresponding author. r.chizzo@unipr.it (R.Chizzolini)

fats introduced. Nutritional guidelines suggest that dietary fat should providebetween 15 and 30% of total calories and that saturated fats should be limited to between 0 and 10% of caloric intake [1]. It is also advised that cholesterol intake should not exceed 300 mg per day. Limitations in fat and cholesterol intakes are thought to be important measures to prevent obesity and hypercholesterolaemia, conditions that are considered to predispose to various chronic diseases of thecirculatory system. Relationships appear to exist, also, between a high-fat intake, especially saturated fat, and an increased risk of some cancers, especially cancers of the colon, breast and prostate [2]. Epidemiological and clinical studies have suggested that high-fat diets, regardless of their fatty acid distribution, increase blood cholesterol concentrations [3±5]. The latter point, though,has been disputed by Nelson et al. [6] who suggested that it is the ratio of the various fatty acids in the diet that determines the changes in blood cholesterol levels upon changes in the dietary fat intake, not the percentage of calories from fat, either saturated or unsaturated. Blood levels of cholesterollow density lipoproteins (LDL) would appear to be una€ected by the percentage of fatcalories in the diet. More speci®cally, it appears that saturated fatty acids of 12±16 carbon atoms increase blood total-, LDL- and HDL-cholesterol concentration and the LDL:HDL ratio [7]. Polyunsaturated o-6 fatty acids tend to decrease LDL-cholesterol levels, while monounsaturated ones are probably essentially neutral with respect to cholesterol. Fatty acids of the o-3 series have not been shown tohave consistent e€ects on blood cholesterol, although long-chain o-3 polyunsaturates are e€ective in reducing blood triacylglycerol levels, a risk factor on their own for cardiovascular disease [8]. Studies dealing with the role of dietary cholesterol on blood cholesterol go as far back as 1956 when Keys et al. [9] studied serum cholesterol level and cholesterol intake. The results indicated thatin the adult man the serum cholesterol level is essentially independent of the cholesterol intake over the whole range of natural human diets. Similarly, Morris et al. [10] and Kahn et al. [11] found no correlation between the levels of serum cholesterol and the daily intake of foods considered rich in cholesterol. Nichols et al. [12] also concluded that blood cholesterol varied from the lowest...