Functional properties of ice cream from milk of dairy cows abomasally infused with increasing amounts of high-oleic sunflower fatty acids

The main challenge to producing a nutritionally improved milk fat composition is to increase monounsaturated fatty acids (MUFA) and decrease saturated fatty acids (SFA) without detriment to dairy product characteristics. Our aim was to determine the optimal amount of intestinally available oleic acid (via abomasal infusion) to produce higher-MUFA milk fat with satisfactory functional characteristics for ice cream. One control and four increasing doses of free fatty acids (FA) from high oleic sunflower oil (HOSFA) were infused into the abomasa of four lactating dairy cows in a changeover design with periods of 7 d. Treatments were (1) control (no FA infused), (2) HOSFA (250 g/d), (3) HOSFA (500 g/d), (4) HOSFA (750 g/d), and (5) HOSFA (1000 g/d). All treatments included meat solubles and Tween 80 as emulsifiers. Ice cream mixes were prepared with butter oil from all treatments. Samples prepared from control and 500 g/d HOSFA infusion were evaluated by a judging panel in a triangle test. Statistical analysis of results showed linear changes in most of the variables analysed as HOSFA infusion increased. For ice cream under freezing temperatures, the 500 g/d level was optimal. Sensory evaluation analysis indicated no statistical difference between ice creams prepared from the control and 500 g/d HOSFA infusion. Changes in 23 triacylglycerol fractions were statistically correlated to functional properties at 10 min of freezing. The decrease in fractions with SFA (butyrin-caprylin-palmitin, butyrin-laurin-olein, butyrin-myristin-palmitin, butyrin-palmitin-palmitin, caproin-myristin-palmitin, butyrin-palmitin-stearin, caproin-palmitin-palmitin) and the increase in dioleyl triglycerides (with butyric, lauric, myristic and palmitic acids) and triolein were some of the most highly correlated with ice cream functional properties as the result of increasing HOSFA infusion. We were able to produce an ice cream with desirable physical and organoleptic qualities, yet containing twice as much oleic acid and two-thirds as much palmitate as a control ice cream.