L.Jagan Mohan Rao, K. Ramalakshmi, in Recent Trends in Soft Beverages, 2011
10.3 Benefits of soft drinks
Soft drinks contribute to the healthy and enjoyable diet. Soft drinks in addition to water also meet the fluid requirement. Besides water, body needs other nutrients for growth, energy and good health. Selected beverages can provide this vital combination of protein, carbohydrate, fat, vitamins, minerals and water. Hence, soft drinks provide part of the total daily intake of liquid and energy. The second area of nutritional significance is the ability of soft drinks to promote rapid uptake of salts and water by body. Soft drinks are the part of balanced diet and healthy lifestyle as these contain health elements like vitamins and calcium. The consumers choose the soft drinks that best suit their lifestyle, tastes, nutritional needs and physiological constraints. Soft drinks provide a refreshing and positive contribution to everyday living. There are three main areas of soft drink’s nutritional significance. The first area is energy; carbohydrates are the important sources of energy. The second area of nutritional significance is rapid uptake of body salts and water by isotonic drinks. The third area is low-calorie forms which are meant for those people who wish to enjoy such beverages with minimum calorie intake. Other nutritional benefits are availability of essential vitamins and minerals [3]. Along with the benefits, the negative side is the development of dental caries. This has been claimed by means of sugar residues in the mouth when an acidic drink is consumed constantly [4].
Nutrients in Soft Drinks
Soft drinks are one of the significant beverage products in this postindustrial era and have become a fast growing sales item in the last few decades. Soft drinks can be classified into several groups based on its sugar contents, carbonation level, ingredients, and functionality. Some soft drinks have been associated with the increased risk of obesity and noncommunicable diseases. In general, soft drinks can be classified into several types including: bottled waters, carbonated water, juice, nectar, squash/syrup, still drinks, iced/ready-to-drink caffeine containing beverages, sports drinks, and energy drinks (Hu and Malik, 2010; Kregiel, 2015).
Soft Drinks
Carbonated soft drinks are commonly known as soda. The name “soft drink” infers that the beverage does not contain alcohol, which is considered a “hard drink.” Carbonated soft drinks are available in types that are sweetened with sugars or with the sugar substitutes that are described in Chapter 4.
The average sweetened soft drink contains 150 calories per 12 ounces. Most of the calories in soft drinks are in the form of refined cane sugar or corn syrup. High fructose corn syrup (HFCS) is used nearly exclusively in the United States as a sweetener because of its lower cost. Unless soft drinks are fortified, they contain little to no fiber, minerals, protein, vitamins, or other essential nutrients. They may also contain artificial colorings and flavorings. Glucose and fructose, two simple sugars in soft drinks, are fermented by oral bacteria that produce acid, which dissolves tooth enamel during the tooth decay process. Many soft drinks are acidic, and some may have a pH of 3.0 or even lower, which adds to the oral acidity.
Some colas contain phosphoric acid, a mineral acid that conveys a tangy taste. Phosphoric acid may withdraw calcium from bones, lowering bone density and contributing to osteoporosis. A high-meat diet (which is also high in phosphorus) compounds the situation. It may be that soft drinks replace calcium-containing foods and beverages in the diet, and this is the greater problem at hand.
Many soft drinks contain varying amounts of caffeine. Caffeine is a safe ingredient that has been added to some soft drinks for more than 100 years. Most of the caffeine in cola drinks is added during the formulation process. Caffeine-reduced and caffeine-free soft drinks are also available. The caffeine content of soft drinks.
Soft drinks are largely produced as acidic beverages (pH 2.5–4.0) and consumed worldwide (Azeredo et al., 2016). Classification of soft drinks can be carried out in several ways. However, soft drinks can be generally defined as nonalcoholic drinks that combine a balance of acidity and sweetness with flavor and color (Ashurst et al., 2017).
The ingredients of soft drinks are water, sweetener, carbon dioxide, flavorings, coloring agents, acidulants, chemical preservatives (within the legal limits), antioxidants, and foaming agents such as saponins (Kregiel, 2015). While regular soft drinks include roughly 90% water, diet soft drinks contain up to 99% water (Azeredo et al., 2016).
Innovations in soft drinks industry encompass development of new tastes, use of low-calorie formulations, natural colorants, and addition of proteins and health-appealing beverages such as herbs and collagen (Azeredo et al., 2016).
Except zero-calorie products, the sugar content of soft drinks varies between 1% and 12%. Glucose, sucrose, or fructose is added to soft drinks as a natural carbohydrate sweetener. Sucrose is disaccharide carbohydrate, consists of glucose and fructose molecules. Glucose, the primary source of energy, is the most extensively used sweetener. Sucrose strengthens and conserves the flavor of beverages and provides a delightful sensation. Thaumatin is the strongest natural sweetener used in food as a flavor modifier which is 2000 times sweeter than sugar. Trehalose, isomaltulose, and d-tagatose are also used as natural carbohydrates in the soft drink production (Kregiel, 2015).
Sugar substitutes provide usually less energy, however, they duplicate the sugar taste. Some of these substitutes are natural and the others are synthetic. In general, synthetic ones are also referred to as artificial sweeteners. The beverage industry is replacing corn syrup or sugar with artificial sweeteners. > 6000 food products contain artificial sweeteners and the number is increasing every year (Tandel, 2011; Sharma et al., 2014). Aspartame, acesulfame potassium (known as acesulfame K), sucralose, saccharin, and cyclamate are used as a sweetener in soft drinks. Aspartame and acesulfame potassium are 200-fold sweeter than sucrose. Aspartame is composed of l-phenylalanine and l-aspartic amino acids. Acesulfame potassium is readily soluble in water but it is neither metabolized nor stored in the body (Kregiel, 2015). Sucralose, a chlorinated carbohydrate, is 600 times sweeter than sucrose. The absorption of sucralose is low in the human body and most of it excretes in feces and urine. It has high level of sweetness, without having calorie. Sucralose consumption is safe for human and its acceptable daily intake is 5 mg/kg body weight (Sharma et al., 2014). Neotame, cyclamate, and erythritol are less used sweeteners in soft drinks. Pectin, guar, locust gum, and xanthan are hydrocolloids which are utilized as stabilizer and thickeners to improve mouthfeel (Kregiel, 2015).
Common acids used in the drinks are citric, succinic, malic, and phosphoric acids. Carbonation process leads to make drinks more acidic and helps to give them tangy flavor and taste. Also, this process helps to extend shelf life of soft drinks. Carbon dioxide can be supplied to soft drinks in solid or liquid forms. The content of carbon dioxide differs from 1.5 to 5 g/L. Acidity regulators are essential agents to improve the taste of soft drinks. Their other vital role is to inhibit microbial growth. The widely used preservatives in soft drinks are sorbic and benzoic acids, and their calcium, potassium, and sodium salts (Kregiel, 2015; Azeredo et al., 2016).
Diet quality
Regular soft drinks usually have a low micronutrient content. There is evidence that regular soft drinks displace nutrient-dense foods such as milk in the diet of children and adolescents (Vartanian et al., 2007). Accordingly, consumption of soft drinks was associated with lower intake of micronutrients such as calcium and folate in German children (Libuda et al., 2009). Such an impaired diet quality is undesirable for the prevention of later, diet-related diseases such as osteoporosis and cardiovascular diseases. Findings from a study in German children and adolescents indicate a stronger diluting effect on diet quality in girls than in boys (Libuda et al., 2009). Since mean diet quality was found to decrease with age in girls, high soft drink consumption might be a cause for concern in adolescent girls in particular.
