Casein Proteins: Structural and Functional Aspects

Abstract

Abstract Mammalian milk is a complex fluid mixture of various proteins, minerals, and lipids, which play an important role in providing nutrition and immunity to the newborn. Casein proteins, which form about 80% of the bovine milk proteins, form large colloidal particles with calcium phosphate to form casein micelles, which for many years have been an important subject of interest. Casein micelles are composed of four main types of proteins: αS1‐casein, αS2‐casein, β‐casein, and k‐casein. These constituent casein proteins lack well‐defined secondary and tertiary structure due to large amount of propyl residues. These micelles are being extensively studied because of their importance in functional behavior of milk and various milk products. However, the exact structure and nature of these casein micelles are still under debate. These different casein proteins possess different functional properties due to their primary amino acid sequence. Abstract Long-haul travel does not constitute an obstacle for tourists to travel and is fast gaining the attention of tourists in new and unique experiences. This study was conducted to identify the long-haul travel motivation by international tourists to Penang. A total of 400 respondents participated in this survey, conducted around the tourist attractions in Penang, using cluster random sampling. However, only 370 questionnaires were only used for this research. Data were analysed using SPSS software 22 version. The findings, ‘knowledge and novelty seeking' were the main push factors that drove long-haul travel by international tourists to Penang. Meanwhile, the main pull factor that attracts long- haul travel by international tourists to Penang was its ‘culture and history'. Additionally, there were partly direct and significant relationships between socio-demographic, trip characteristics and travel motivation (push factors and pull factors). Overall, this study identified the long-haul travel motivations by international tourists to Penang based on socio-demographic, trip characteristics and travel motivation and has indirectly helped in understanding the long-haul travel market particularly for Penang and Southeast Asia. This research also suggested for an effective marketing and promotion strategy in pro- viding useful information that is the key to attract international tourists to travel long distances. Keywords: