Acid whey-based smoothies with probiotic strains

The aim of study was to determine potential applications of acid whey in the production of whey-based beverages containing plant-based ingredients in equal proportions to acid whey (1:1): beverage 1 with the addition of carrot, rosehip and sea-buckthorn purée; beverage 2 with addition of pear purée and sour cherry juice; beverage 3 with the addition of parsley and banana purée. The composition and mineral content of acid whey were determined. Whey-based beverages containing fruit and vegetables were analysed for mineral content, sensory attributes and the survivability of Lactobacillus rhamnosus HN001 probiotic bacteria. Acid whey is characterised by a low content of major milk components, namely fat (0.441 g kg-1), protein (2.978 g kg-1), especially of whey protein in native form (0.052 g kg-1), lactose (42 g kg-1) and lactic acid (6.304 g kg-1). Acid whey is abundant in mineral nutrients, including calcium (1199 mg kg-1), magnesium (87.1 mg kg-1) and potassium (1533 mg kg-1). The mineral analysis revealed that the addition of fruit and vegetables increased the iron content of beverages 2 and 3, and the content of potassium and magnesium in beverage 3. Beverage 3 (100 g) met the Recommended Dietary Allowances (RDA) for potassium and magnesium in 25% and 15%, respectively, in children aged 4 to 7. Whey-based beverages had uniform colour and consistency. The predominant taste and aroma were those associated with the fruit and vegetables, followed by some sweet flavour and aroma, whereas the acidic flavour was moderately discernible. All beverages containing fruit and vegetables received very high scores in a sensory evaluation. The survival of the probiotic strain was monitored for two weeks during which bacterial counts remained stable at 7 log cfu ml-1. Smoothies based on acid whey with the addition of fruit and vegetables and the probiotic strain are functional foods that are recommended for people with nutrient deficiencies.