Abstract Powdered milk products for children (Growing Up Milk Powders or GUMPs) containing added carbohydrates such as glucose and sucrose are now well established in parts of Asia. We surveyed GUMPs in Malaysia and Indonesia to determine the content of added carbohydrates. The ingredient lists and nutrition information panels were used to calculate the percentage of declared carbohydrates contributed by added carbohydrates and a subset of seven products was tested for their glycemic index (GI) and insulin responses in healthy adults. The glycemic load for each product was calculated. In total, 58 products (n = 24 in Malaysia and n = 34 in Indonesia) were surveyed. Added carbohydrate content (excluding fibre) ranged from 0 to 21.5 g per serve. Milk powders without added sources of carbohydrate had similar GI values to standard liquid whole milk. Products containing maltodextrins, corn or glucose syrups increased the GI by more than 2-fold, and glycemic load (GL) by 7-fold compared to milk powders with no added carbohydrates. Insulin responses were significantly but not strongly correlated with glucose responses (r = 0.32, p < 0.006). Children's milk powders containing higher levels of added carbohydrate ingredients elicit higher glucose and insulin responses than liquid or powdered whole milk. Keywords: milk, carbohydrate, glycemia, insulinemia, glycemic index

1. Introduction Milk and dairy products are staples of children's diets in countries with a long tradition of dairying, and increasingly in countries of Asia where dairying is still largely absent. In western countries, dairy products are recommended as one of the 4–5 food groups in official dietary guidelines. Milk contributes high quality protein and significant quantities of micronutrients, including calcium, riboflavin, vitamin A and zinc. More recently milk is being used as a delivery vehicle for other nutrients such as vitamin D and iron. In Asian countries, a new category of high value milk products for children known as Growing Up Milk Powders (GUMPs) has become established in a short timeframe [1]. They are perceived by health professionals and carers as a valuable supplement to children's diets to help ensure they obtain adequate nutrition, particularly if the diet is generally poor. Unfortunately, there is a growing trend for manufacturers to incorporate additional carbohydrates such as sucrose, maltodextrins and corn or glucose syrups. Some of these ingredients may be useful in small amounts to increase palatability and encourage consumption of an otherwise bland food. But many products contain high levels of added carbohydrates without detectable sweetness that dilute the nutritional value of the milk. The additional calories and higher energy density may contribute to the trend of increasing overweight and obesity among children in Asia [2]. Discretionary calories are also more concerning if they have the capacity to stimulate excessive postprandial hyperglycaemia and insulinemia. Postprandial glycaemia has dose-related harmful effects that increase the risk of obesity, type 2 diabetes and coronary heart disease [3,4,5]. The current research was therefore undertaken to determine the extent to which additional carbohydrates were being incorporated into GUMPs for children in two Asian countries (Malaysia and Indonesia), and to assess the impact of a selection of these products on blood glucose and insulin responses. The glycemic index (GI) and insulin index (II) were determined according to standardised protocols.

2. Experimental Section A total of 58 GUMPs (24 from Malaysia and 34 from Indonesia) were surveyed for total and added carbohydrate content. The ingredient lists and nutrition information panels were used to calculate the percentage of declared carbohydrates coming from added sources of sugars and refined carbohydrate ingredients, excluding dietary fiber ingredients (e.g., inulin). In Indonesia, but not Malaysia, the total carbohydrate declaration on the Nutrition Information Panel generally includes fiber. The carbohydrate, protein and fat content of standard full cream and non-fat milk powder were used for reference [6]. A sub-set of 7 products ( ) was selected to be representative of those available with a range of added carbohydrate contents. They included GUMPs with no added carbohydrates and those with high levels of mono- or disaccharides and/or maltodextrins (i.e., short chain glucose polymers). Equivalent carbohydrate portions (25 g) were tested for their GI according to the International Standards Organisation methodology [7]. All experimental procedures were conducted in accordance with ethical research in human subjects, and the protocol was approved by the Human Research Ethics Committee of the University of Sydney. Table 1 Product Energy (kJ) Total CHO 1 (g) Added CHO 1 (g) Fibre (g) Protein (g) Fat (g) Serve Size Tested 2 (g) Normal Serve Size 3 (g) CHO 1 per Normal Serve 4 (g) 1 a 152.1 25.0 15.3 0.8 4.3 4.0 36 40 28.0 2 b 176.0 25.0 13.0