The Influence of Whey Protein Isolate on the Quality Indicators of Acidophilic Ice Cream Based on Liquid Concentrates of Demineralized Whey

The use of liquid whey concentrates in the composition of ice cream, especially in combination with other powdered whey proteins, is limited due to their understudied properties. This article shows the main rheological and thermophysical characteristics of ice cream mixes, as well as color parameters, microstructure, analysis of ice crystals and quality indicators of ice cream during storage. The most significant freezing of free water (p ≤ 0.05) was observed in the temperature range from the cryoscopic temperature to -10 °C. The microscopy of experimental ice cream samples based on hydrolyzed whey concentrates indicates the formation of a homogeneous crystalline structure of ice crystals with an average diameter of 13.75-14.75 μm. Microstructural analysis confirms the expediency of using whey protein isolate in ice cream, which ensures uniform distribution of air bubbles in the product and sufficient overrun (71.98-76.55%). The combination of non-hydrolyzed whey concentrate and 3% whey protein isolate provides the highest stability to preserve the purity and color intensity of the ice cream during storage. The produced ice cream can be classified as probiotic (number of Lactobacillus acidophilus not lower than 6.2 log CFU/g) and protein-enriched (protein supply from 15.02-18.59%).

Quality specification of ice creams produced with different homofermentative lactic acid bacteria

This study investigated the changes in the physicochemical, microbiological, textural, and nutritional values of ice cream produced by various methods with the addition of different lactic acid bacteria. Adding lactic acid bacteria to the ice cream mix caused a decrease in firmness, consistency, cohesiveness, index of viscosity, pH, aw, first drop, complete melting, and overrun values (p < .05). These decreases were more pronounced in the samples to which lactic acid bacteria were added before mix maturation (p < .05). Firmness and consistency values varied between 15.11-16.26 (g) and 374.58-404.91 (g s), respectively, in the samples to which lactic acid bacteria were added before maturation. No significant effect of the addition of lactic acid bacteria to the ice cream mix on the L*, a*, and b* values of the bacteria before or after mix maturation was detected (p > .05). The L* values of the samples varied between 88.91 and 83.36, a* values between 0.76 and 1.32, and b* values between 6.57 and 8.38. An increase was detected in the amount of organic acid (excluding formic acid) in the samples produced with the addition of different lactic acid bacteria (p < .05). The number of fatty acids in the samples varied depending on the lactic acid addition and the production method; the rate of this change was generally higher in the samples with added lactic acid bacteria after mix maturation (p < .05). In particular, the amounts of short- and medium-chain fatty acids increased in the samples with lactic acid bacteria added after mix ripening, compared to the control sample.

An Investigation of Several Physicochemical Characteristics, as Well as the Cholesterol and Fatty Acid Profile of Ice Cream Samples Containing Oleogel, Various Stabilizers, and Emulsifiers

This study investigated the possible usage of beeswax oleogels instead of milk fat as a fat source in ice cream production and konjac gum as a stabilizer instead of salep. For this aim, 12 different ice cream samples were prepared using various fat and oil sources (milk fat and oleogel), stabilizers (salep and konjac gum), and emulsifiers (monoglyceride (MG), Palsgaard (PG), and no emulsifier/emulsifier-free (NE)). It was determined that the overrun ratio of ice cream samples containing milk fat was higher than that of samples containing oleogel, and the viscosity of the ice cream mix containing Palsgaard and oleogel was greater than that of the mix with other treatments (milk fat, MG, and NE). While the first dripping time of the samples with PG and konjac gum was longer compared to the samples without emulsifier (NE) or monoglyceride (MG), the complete melting times of the samples were close to each other. Whereas the dissolution rate of the samples with salep was higher than that of the samples with konjac gum, the fat destabilization ratios of the samples with oleogel and konjac gum were lower than those of the samples with milk fat and salep. The fat destabilization ratio of samples containing PG as an emulsifier was statistically higher (p < 0.01) than that of samples containing MG and NE. It was found that the unsaturated fatty acid (C18:1, C18:2, and C18:3) content of the samples containing oleogel was significantly higher (p < 0.01) than that of the samples containing milk fat. However, butyric and caproic acids, which are aliphatic fatty acids, were found to be deficient in the samples to which oleogel was added instead of milk fat. As to the microscopic appearance, while water and oil particles were not homogeneously dispersed in the ice cream samples with oleogel, they were fully homogeneously dispersed in the milk fat-added ice cream samples. In addition, it was determined that panelists preferred the samples with added milk fat as fat source, salep, and PG as emulsifier. Among the samples with added oleogel as the oil source, they liked the sample added with oleogel as fat source, konjac gum, and no emulgator more.

Microstructural, Physicochemical, Microbiological, and Organoleptic Characteristics of Sugar- and Fat-Free Ice Cream from Buffalo Milk

Ice cream is a popular dessert product across the world. Structure, body, taste, and odor properties are created by adding non-milk ingredients and milk ingredients. The main aim of the study is to decrease the caloric value of ice cream by using sugar and fat replacements. Ice cream treatments were investigated based on microstructural, chemical, physical, microbiological, sensory, and calorific values. Four different ice creams were used (control ice cream (SC1), ice cream with stevia (SC2), ice cream with sucralose (SC3), and ice cream with sorbitol (SC4)). The chemical properties in all treatments of ice cream were significantly recorded (p < 0.05). The highest sucrose and fat levels were detected in the SC1 treatment compared with the other treatments (p < 0.05). The lowest fat and sugar amounts were observed in the SC2, SC3, and SC4 treatments (p < 0.05). The highest viscosity, overrun, and hardness values (p < 0.05) were detected in the control ice cream. Total aerobic mesophilic bacterial counts were not significantly recorded between different ice cream treatments (p < 0.05). The sensory scores were not significantly affected by sweeteners and bulk agents in the different treatments. The highest calorific value was calculated in the SC1 samples (p < 0.05). On the other hand, the lowest calorific value was calculated in SC2, followed by the SC3 and SC4 treatments. In scanning electron microscopy (SEM), the gel exhibited a homogeneous structure with a fine network within the SC2, SC3, and SC4 treatments, as it contained a cohesive structure with small-sized pores.

STUDIES OF WATER FREEZING FEATURES IN ICE CREAM WITH STARCH SYRUP

The purpose of the study is to research the process of water freezing in new types of ice cream with starch syrup at certain stages of the technological process. Starch syrup as a degradation product of corn starch is characterized by different values of the dextrose equivalent (DE). Starch syrup is a source of solids, sweetener, cryoprotectants (at high DE) and thickener (for low values of DE). The starch syrups  with fundamentally different functional and technological properties are chosen for the study: high glucose-fructose syrup HGFS-98 (DE = 98) and low-sugar starch syrup GFS-30 (DE = 30). To determine the size of ice crystals in ice cream, a light microscope of the brand XS-2610 with a cooling chamber is used for an increase of x600, and the cryoscopic temperature is measured by cryostat and Beckmann thermometer (TL-1) to calculate the content of frozen out water. The regularities of the process of water freez-out in ice cream with milk fat content of 3.5%, creamy fat content of 10% and filling with fat content of 15% in the temperature range from minus 6ºС to minus 40ºС are established. In particular, the content of frozenwater in ice-cream at certain stages of the technological process is determined. The results are used to optimize the prescription composition of ice cream with starch syrup. It is recommended to use hydrocarbon complexes consisting of HGFS-98 and GFS-30 in the ratio of 30:70 to 80:20 to reduce the content of frozen water in ice cream of different chemical compositions. The results of the study are of practical importance and allow to obtain in production conditions the fine-crystalline structure of ice cream with starch syrup.

Sensory Profile, Drivers of Liking, and Influence of Information on the Acceptance of Low-Calorie Synbiotic and Probiotic Chocolate Ice Cream

The objective of this study was to evaluate the sensory profile and the influence of the information on the acceptance of the symbiotic chocolate ice cream made with sucrose and different sweeteners (aspartame, sucralose, neotame, Stevia with 60%, 85%, 95%, and 97% of rebaudioside A) through analysis of variance (ANOVA), Tukey's test, and partial least of square (PLS) regression. Quantitative descriptive analysis (QDA) was carried out by 18 assessors, who evaluated the samples in relation to the raised descriptors. Additionally, two acceptance tests (blind/informed) were performed with 120 consumers. The samples sweetened with sucralose and rebaudioside 97% presented similar profile to the control sample, thus having a better potential to replace sucrose in chocolate ice cream. The acceptance test carried out with information had higher scores for the attributes appearance, aroma, flavor, texture, and overall impression. The correlation between data from the acceptance tests and QDA showed that the descriptors "low-energy" and "natural sweetener" claims interfered negatively in the drivers of liking of chocolate ice cream. Therefore, we can conclude that some characteristics unnoticed by consumers were highlighted after providing the information about the product's characteristics.

PRACTICAL APPLICATION

This research is important and contributes to the manufacture and development of low-calorie chocolate ice cream with functional properties, guiding, through suitable sensory and statistical tools, the application of stevia and other artificial sweeteners in products with reduction or total absence of sucrose and highlighting the impact of the labeling of these products on consumer perception.