Archive for the ‘Food’ Category

One Stop Shop for Essential Oils Chromatograms

In the past few months, we have collected a variety of chromatograms using two different column phases, and three different column dimension formats. The peak identifications were performed using some standards but mostly from the NIST MS EI spectra library, 2005 edition. Let us know what you think in the comments below. Citronella Java GC_FF1296 […]

Analyzing avocado: How to deal with lack of water and keep the fats out

Avocados are a popular produce item. In fact, the consumption of avocados rose by 450% since 2000! The good news – avocados are ranked number 1 on the clean 15 list, meaning they have the least amount of pesticide residues. With so many avocados on the market, the testing is as important as ever, which […]

Are Wax columns always used for essential oils?

My last blog examined the analysis of essential oils using GC columns with wax phases. While these columns are commonly used for natural oils, they are not the only option. Another choice that falls on the other end of the selectivity spectrum, in this case, a non or low polar; dimethyl diphenyl polysiloxane stationary phase. […]

A closer look at selectivity and tailing: Essential oils and Wax phases

The most common way to analyze essential oils is to use GC with either a FID or MS. The wax-based columns are the number one choice for many users and following up on an excellent blog post by Corby, I wanted to evaluate two wax in Restek inventory: Stabilwax and Rtx-Wax. The essential oil we chose was […]

Falling Victim to One of LC’s Classic Blunders: Mismatching Your Diluent and Mobile Phase

An early lesson most of us learn in liquid chromatography is this: Always match your diluent to your mobile phase.  Once the exams are done, if you learned this in a college course, or your manager has walked away, you start flexing this “requirement” a little to see how matched they really need to be.  […]

Determining Optimal LC-MS/MS MRMs: Sensitivity is NOT Everything!

LC-MS/MS using electrospray ionization (ESI) is a widely used platform for routine target analysis and quantitation. However, one big challenge faced through the use of ESI is the presence of matrix effects. So, what are matrix effects and why are they important? Simply put, when matrix components coelute with the target analytes, they have the […]

Analyzing orange: peel and pulp separately or as whole?

Up to this point, I’ve focused on the optimization of QuEChERS salts and dSPE cleanup with fairly homogenous matrices. So, what about oranges? Should I peel them and analyze only the pulp? After all, that is the edible part. The peel is used as well – pressed into essential oils or scraped into zest. Besides, […]

Thrive with the New Rxi-65…TG!

Introducing our new and improved GC stationary phase: The Rxi-65TG! This column is essential for analyzing triglycerides in edible oils! You may be asking yourself, why the need for a new 65-type phase? Well, we certainly were not happy with the way our current Rtx-65TG was performing. After redeveloping the polymer and using Rxi technology, […]

How Can You Make Food Homogenization Less of a Grind?

Sample preparation of a food matrix is only as good as the initial homogenization of your sample.  This determines how representative and effective your extraction will be.  There are multiple ways to homogenize, grind or comminute your sample.  Some involve a simple grind in a food processor.  Other methods require expensive instrumentation to cryogenically freeze […]

A Hoppy Little Story

Now that we’re getting into the warmer months of the year, you’re probably starting to see pop-up beer gardens or people outside relaxing with a nice cold one. Since the beer industry has been evolving and people are enjoying craft beers more and more, there are tons of unique brews on the market. If you […]