Effect of Preheating Treatment before Defatting on the Flavor Quality of Skim Milk

Abstract

Skim milk has a poor flavor due to the lack of fat. Finding ways to improve the flavor quality of skim milk has attracted the attention of more and more researchers. The purpose of this study was to create a skim milk product with good flavor by processing. Briefly, raw milk was treated by preheating at pasteurization (85 °C, 15 s) and ultra-high temperature (UHT) instantaneous sterilization (137–141 °C, 4 s). Subsequently, the sample was centrifuged to remove fat and obtain two kinds of skim milk, namely, PSM (skim milk obtained by preheating at 85 °C, 15 s) and USM (skim milk obtained by preheating at 137–141 °C, 4 s). The results showed that the intensity of the main sensory attributes (overall liking, milk aroma, etc.) and the concentrations of the key flavor compounds (2-heptanone, 2-nonanone, decanal, hexanoic acid, etc.) were significantly higher in the USM (p < 0.05) than that of the PSM and RSM (skim milk without preheating). Principal component analysis (PCA) with E-Nose (electronic nose) showed that the RSM had significant differences in the milk aroma compared with the PSM and USM. Furthermore, it was found that there were good relationships between volatile compounds and sensory attributes by partial least squares regression (PLSR) analysis. These findings provided insights into improving the flavor quality of skim milk by preheating treatment instead of any flavor additives.

Comparative Analysis of Characteristic Volatile Compounds in Five Types of Infant Nutrition Powders by HS-GC-IMS and GC-MS

“…At the same time, these flavor compounds played a crucial role in the formation of nutritional powder flavor [ 23 ]. Low concentrations of aldehydes usually have a grassy taste and sweetness, while high concentrations may produce an odor [ 24 ].…”

Dietary Effect of Brevibacillus laterosporus S62-9 on Chicken Meat Quality, Amino Acid Profile, and Volatile Compounds

“…The precursors of meat aroma substances were various types of small biological molecules which originated from the water-soluble extracts of meat. The soluble components produced meat aroma under heating, which could be summarized in three pathways: the first, by the oxidation and hydrolysis of lipids to form compounds such as aldehydes, ketones, and alcohols [61]; the second, reactions such as the Maillard reaction [62] or the decomposition and oxidation of sugars and amino acids to form volatile and non-volatile compounds; the third, reactions between the products of the two pathways above to produce numerous aroma components. As the chicken was rich in polyunsaturated fatty acids, making it easy to the oxidation of lipids [63], it was expected to be rich in volatile compounds (i.e., aldehydes, alcohols, and ketones) produced by the oxidation of lipids and fatty acids [64].…”

Survey of Dairy Products Using Machine Learning Techniques

“…Consequently, consumption of such compromised milk or dairy products may give rise to situations jeopardizing human health. Dairy quality affects the nutritional value of dairy products and public health, so quality and safety standards are essential to ensure healthy and safe products for consumers [6] [7]. With the widespread developments in technology, there has been a need to use Artificial Intelligent (AI) in the processes of detecting and classifying the quality of dairy products, as they have an important role in their usefulness.…”