Next Article in Journal
Influences of Biodynamic and Conventional Farming Systems on Quality of Potato (Solanum Tuberosum L.) Crops: Results from Multivariate Analyses of Two Long-Term Field Trials in Sweden
Previous Article in Journal
Optimising the Encapsulation of an Aqueous Bitter Melon Extract by Spray-Drying
Article Menu

Export Article

Open AccessArticle
Foods 2015, 4(3), 420-439; doi:10.3390/foods4030420

A Pilot Investigation of the Relationship between Climate Variability and Milk Compounds under the Bootstrap Technique

Department of Organic Food Quality and Food Culture, University of Kassel, Nordbahnhofstr. 1a, 37213 Witzenhausen, Germany
Meteorological Institute, University of Bonn, Auf dem Hügel 20, 53121 Bonn, Germany
Author to whom correspondence should be addressed.
Academic Editor: Christopher J. Smith
Received: 15 May 2015 / Revised: 28 July 2015 / Accepted: 13 August 2015 / Published: 11 September 2015
View Full-Text   |   Download PDF [1170 KB, uploaded 11 September 2015]   |  


This study analyzes the linear relationship between climate variables and milk components in Iran by applying bootstrapping to include and assess the uncertainty. The climate parameters, Temperature Humidity Index (THI) and Equivalent Temperature Index (ETI) are computed from the NASA-Modern Era Retrospective-Analysis for Research and Applications (NASA-MERRA) reanalysis (2002–2010). Milk data for fat, protein (measured on fresh matter bases), and milk yield are taken from 936,227 milk records for the same period, using cows fed by natural pasture from April to September. Confidence intervals for the regression model are calculated using the bootstrap technique. This method is applied to the original times series, generating statistically equivalent surrogate samples. As a result, despite the short time data and the related uncertainties, an interesting behavior of the relationships between milk compound and the climate parameters is visible. During spring only, a weak dependency of milk yield and climate variations is obvious, while fat and protein concentrations show reasonable correlations. In summer, milk yield shows a similar level of relationship with ETI, but not with temperature and THI. We suggest this methodology for studies in the field of the impacts of climate change and agriculture, also environment and food with short-term data. View Full-Text
Keywords: climate variability; THI; ETI; milk compounds; bootstrap; uncertainty; Iran climate variability; THI; ETI; milk compounds; bootstrap; uncertainty; Iran

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Scifeed alert for new publications

Never miss any articles matching your research from any publisher
  • Get alerts for new papers matching your research
  • Find out the new papers from selected authors
  • Updated daily for 49'000+ journals and 6000+ publishers
  • Define your Scifeed now

SciFeed Share & Cite This Article

MDPI and ACS Style

Milani, M.R.M.; Hense, A.; Rahmani, E.; Ploeger, A. A Pilot Investigation of the Relationship between Climate Variability and Milk Compounds under the Bootstrap Technique. Foods 2015, 4, 420-439.

Show more citation formats Show less citations formats

Related Articles

Article Metrics

Article Access Statistics



[Return to top]
Foods EISSN 2304-8158 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top